DE10316459A1 - Operating motor vehicle with drive engine, clutch and gearbox in drive train, especially for controlling gearbox, involves adapting friction value, especially using electronic clutch management - Google Patents

Abstract

The motor vehicle has a drive engine, a clutch and a gearbox in its drive train. The method of operating the vehicle, especially to control the gearbox, involves adapting the friction value by comparing the clutch torque with the engine torque and adapting the clutch characteristic depending on the result.

Description

The invention relates to a method, a device and the use thereof for Operation of a motor vehicle, with a drive motor, a clutch and / or a transmission in the drive train, in particular for controlling the transmission.

Referring to FIG. 1, a vehicle 1, a drive unit 2 such as a motor or an internal combustion engine, on. Furthermore, a torque transmission system 3 and a transmission 4 are arranged in the drive train of the vehicle 1 . In this embodiment, the torque transmission system 3 is arranged in the power flow between the engine and the transmission, with a drive torque of the engine via the torque transmission system 3 to the transmission 4 and from the transmission 4 on the output side to an output shaft 5 and to a downstream axis 6 and to the wheels 6 a is transmitted.

The torque transmission system 3 is a clutch, such as. B. designed as a friction clutch, multi-plate clutch, magnetic powder clutch or torque converter clutch, the clutch can be a self-adjusting or a wear-compensating clutch. The transmission 4 is an uninterruptible manual transmission (USG). According to the idea of the invention, the transmission can also be an automated manual transmission (ASG), which can be shifted automatically by means of at least one actuator. In the following, an automated manual transmission is to be understood as an automated transmission which is shifted with an interruption in tractive force and in which the shifting operation of the transmission ratio is carried out in a controlled manner by means of at least one actuator.

Furthermore, an automatic transmission can also be used as the USG, with a Automatic transmission is a transmission with essentially no interruption in tractive power Switching operations is and usually built up by planetary gear stages is.

Furthermore, a continuously variable transmission, such as a conical pulley belt transmission, can be used. The automatic transmission can also be designed with a torque transmission system 3 arranged on the output side, such as a clutch or a friction clutch. The torque transmission system 3 can furthermore be designed as a starting clutch and / or a reversing set clutch for reversing the direction of rotation and / or a safety clutch with a selectively controllable, transferable torque. The torque transmission system 3 can be a dry friction clutch or a wet friction clutch that runs, for example, in a fluid. It can also be a torque converter.

The torque transmission system 3 has a drive side 7 and an output side 8 , wherein a torque is transmitted from the drive side 7 to the output side 8 by z. B. the clutch disc 3 a by means of the pressure plate 3 b, the plate spring 3 c and the release bearing 3 e and the flywheel 3 d is subjected to force. For this application, the release lever 20 is actuated by means of an actuator, for. B. an actuator operated.

The torque transmission system 3 is controlled by means of a control unit 13 , such as, for. B. a control unit, which may include the control electronics 13 a and the actuator 13 b. In another advantageous embodiment, the actuator 13 b and the control electronics 13 a can also be in two different units, such as. B. housings.

The control unit 13 can contain the control and power electronics for controlling the drive motor 12 of the actuator 13 b. This can for example advantageously achieved that the system as a single space b the installation space for the actuator 13 required with electronics. The actuator 13 b consists of the drive motor 12 , such as. B. an electric motor, the electric motor 12 via a gear such. B. a worm gear, a spur gear, a crank gear or a threaded spindle gear acts on a master cylinder 11 . This effect on the master cylinder 11 can take place directly or via a linkage.

The movement of the output part of the actuator 13 b, such as. B. the master cylinder piston 11 a, is detected with a clutch travel sensor 14 , which the. Position or position or the speed or the acceleration of a variable is detected, which is proportional to the position or engagement position or the speed or acceleration of the clutch. The master cylinder 11 is via a pressure medium line 9 , such as. B. a hydraulic line, connected to the slave cylinder 10 . The output element 10 a of the slave cylinder is with the disengaging means 20 , for. B. a release lever, operatively connected so that a movement of the output part 10 a of the slave cylinder 10 causes the disengaging means 20 is also moved or tilted to control the torque transmitted by the clutch 3 .

The actuator 13 b for controlling the transmissible torque of the torque transmission system 3 can be actuatable by pressure medium, ie it can have a pressure medium transmitter and slave cylinder. The pressure medium can be, for example, a hydraulic fluid or a pneumatic medium. The actuation of the pressure medium transmitter cylinder can take place by means of an electric motor, wherein the electric motor provided as the drive element 12 can be controlled electronically. The drive element 12 of the actuator 13 b, besides an electromotive drive element, another, for example, be pressure-actuated drive member. Magnetic actuators can also be used to adjust a position of an element.

In the case of a friction clutch, the transferable torque is controlled in that the friction linings of the clutch disc are pressed in a targeted manner between the flywheel 3 d and the pressure plate 3 b. About the position of the disengagement means 20 , such as. B. a release fork or a central release, the application of force to the pressure plate 3 b or the friction linings can be controlled in a targeted manner, the pressure plate 3 b being moved between two end positions and being able to be set and fixed as desired. One end position corresponds to a fully engaged clutch position and the other end position corresponds to a fully disengaged clutch position. To control a transmissible torque, which is, for example, less than the engine torque currently present, a position of the pressure plate 3 b can be controlled, for example, which lies in an intermediate region between the two end positions. The clutch can be fixed in this position by means of the targeted actuation of the disengaging means 20 . However, it is also possible to control transmissible clutch torques that are defined above the engine torques currently pending. In such a case, the currently occurring engine torques can be transmitted, the torque irregularities in the drive train being damped and / or isolated in the form of, for example, torque peaks.

To control the torque transmission system 3 , sensors are also used which at least temporarily monitor the relevant variables of the entire system and deliver the state variables, signals and measured values necessary for control, which are processed by the control unit, with a signal connection to other electronic units, such as, for example Engine electronics or an electronics of an anti-lock braking system (ABS) or an anti-slip control (ASR) can be provided and can exist. For example, the sensors detect speeds such as wheel speeds, engine speeds, the position of the load lever, the throttle valve position, the gear position of the transmission, an intention to shift and other vehicle-specific parameters.

Fig. 1 shows that a throttle sensor 15, an engine speed sensor 16 and a speedometer sensor may find use 17 and transmit measured values or information to the controller 13. The electronics unit, such as. B. a computer unit, the control electronics 13 a processes the system input variables and forwards control signals to the actuator 113 b.

The gear is as z. B. stage change gear designed, the gear ratios are changed by means of a shift lever 18 or the transmission is operated or operated by means of this shift lever 18 . Furthermore, at least one sensor 19 b is arranged on the shift lever 18 of the manual transmission, which detects the intention to shift and / or the gear position and forwards it to the control unit 13 . The sensor 19 a is articulated on the transmission and detects the current gear position and / or an intention to shift. The intention to shift is detected using at least one of the two sensors 19 a, 19 b in that the sensor is a force sensor which detects the force acting on the shift lever 18 . Furthermore, the sensor can also be designed as a displacement or position sensor, the control unit recognizing an intention to switch from the change in the position signal over time.

The control unit 13 is at least temporarily in signal connection with all sensors and evaluates the sensor signals and system input variables in such a way that the control unit issues control or regulation commands to the at least one actuator 13 b as a function of the current operating point. The drive motor 12 of the actuator 13 b, z. B. an electric motor receives from the control unit, which controls the clutch actuation, a manipulated variable as a function of measured values and / or system input variables and / or signals of the connected sensors. For this purpose, a control program is implemented in the control unit 13 as hardware and / or as software, which evaluates the incoming signals and calculates or determines the output variables on the basis of comparisons and / or functions and / or characteristic maps.

The control unit 13 has advantageously implemented a torque determination unit, a gear position determination unit, a slip determination unit and / or an operating state determination unit or is in signal connection with at least one of these units. These units can be implemented by control programs as hardware and / or as software, so that by means of the incoming sensor signals, the torque of the drive unit 2 of the vehicle 1 , the gear position of the transmission 4 and the slip that prevails in the area of the torque transmission system 3 and the current operating state of the vehicle 1 can be determined. The gear position determination unit uses the signals from the sensors 19 a and 19 b to determine the currently engaged gear. The sensors 19 a, 19 b are articulated on the shift lever and / or on internal transmission means, such as a central shift shaft or shift rod, and detect them, for example the position and / or the speed of these components. Furthermore, a load lever sensor 31 on the load lever 30 , such as. B. on an accelerator pedal, which detects the load lever position. Another sensor 32 can function as an idle switch, ie when the load lever 30 or accelerator pedal is actuated, this idle switch 32 is switched on and when the load lever 30 is not actuated, it is switched off, so that digital information can be used to identify whether the load lever 30 is actuated. The load lever sensor 31 detects the degree of actuation of the load lever 30 .

Fig. 1 shows in addition to the load lever 30 and the sensors associated therewith a brake actuating element 40 for actuating the service brake or the parking brake, such as. B. a brake pedal, a hand brake lever or a hand or foot operated actuator of the parking brake. At least one sensor 41 is arranged on the actuating element 40 and monitors its actuation. The sensor 41 is, for example, a digital sensor, such as. B. designed as a switch, which detects that the brake actuator 40 is operated or not. With the sensor 41 , a signal device such. B. a brake light, are in signal connection, which signals that the brake is applied. This can be done for both the service brake and the parking brake. However, the sensor 41 can also be designed as an analog sensor, such a sensor, such as a potentiometer, determining the degree of actuation of the brake actuating element 41 . This sensor can also be in signal connection with a signal device.

The following is a possible embodiment of the invention presented here described, in which a suitable coefficient of friction adaptation is provided to in particular to increase the switching comfort.

With a possible adaptation of the coefficient of friction, in particular with an electronic clutch management (EKM) and with an automated manual transmission (ASG), the engine torque balance can be used during the slip phases

J. ≙ _Mot = M _Mot - M _Kupp

a comparison of the clutch torque with the engine torque can be performed. Depending on this comparison result, an adjustment of the clutch characteristic curve can then be carried out, in which the coefficient of friction is corrected appropriately. The start-up phase as well as the engagement phase or other phases after the gearshifts can be evaluated as slip phases. Additional boundary conditions can also be provided, such as | ≙ _Mot | <≙ _Max . It is possible that other boundary conditions can also be used.

• a) Ein extrem zu hoher Reibwert kann relativ schnell nach unten korrigiert werden, da hier die Voraussetzung, wie zum Beispiel lange Schlupfphasen oder dergleichen, gegeben sind.
• b) Ein extrem zu niedriger Reibwert kann nur langsam nach oben korrigiert werden, da hier die Voraussetzung bei Einkuppelphasen aufgrund der kurzen Schlupfphasen prinzipiell nicht mehr gegeben sind.

The following properties of the intended coefficient of friction adaptation result:

• a) An extremely high coefficient of friction can be corrected relatively quickly downwards, since here the prerequisites, such as long slip phases or the like, are given.
• b) An extremely low coefficient of friction can only be corrected slowly upwards, since the prerequisites for engagement phases due to the short slip phases are no longer present here.

This can be particularly useful when commissioning in the vehicle factory, for example too high a touch point due to incomplete ventilation be taught. This behavior compensates for the coefficient of friction adaptation in which the Coefficient of friction drops sharply; especially to the lower limit. During the Air can escape from the system during the first switching operations. The touch point can can be corrected relatively quickly using the touch point adaptation. The coefficient of friction can then do not follow the rapid touch point adaptation and this can continue to assume low values. As a result, the driver can experience an extreme result in uncomfortable switching, d. H. there is a hard disengaging and engaging.

Because of the properties mentioned above Coefficient of friction adaptation, namely to act relatively quickly when the coefficient of friction is too high while in In the opposite direction, the adaptation can react significantly slower or not at all the invention presented here that the coefficient of friction adaptation is suitably adapted to these properties.

• - Die Reibwertadaption konnte aufgrund zu kurzer Schlupfdauer bei einer Schaltung nicht durchgeführt bzw. ausgewertet werden, und/oder
• - die Schlupfdauer ist für die spezielle Schaltung bei gegebenem Drehzahlsprung zu kurz.

Certain criteria can be set up, such as the following:

• - The coefficient of friction adaptation could not be carried out or evaluated due to the slip period being too short, and / or
• - The slip duration is too short for the special gear shift at a given speed jump.

It is also possible to determine other criteria to determine the inventive one To further improve friction coefficient adaptation. When checking whether the aforementioned or other criteria exist, it can be provided that the coefficient of friction either absolutely by a certain proportion and / or relatively by a certain Percentage is increased. In this way it can be ensured that the Adaptation of the coefficient of friction from the so-called deadlock situation described at the beginning can adapt again. This means that the coefficient of friction is appropriate can increase. The usual slip duration can be reached due to the increasing coefficient of friction be so that a normal evaluation of the coefficient of friction adaptation in an advantageous Way can be done.

As part of an advantageous development of the present invention, the friction coefficient adaptation according to the invention can also be further simplified. Preferably, e.g. B. below a predetermined coefficient of friction, for example at each adaptation phase, the evaluation of the adaptation anticipates a certain, more fixed one increasing proportion are taken into account. If this proportion is smaller than the maximum permissible change in the adaptation, this would also mean that desired behavior can be ensured. It is also possible for others To make changes in the coefficient of friction adaptation to the total of the invention Simplify procedures further. This type of friction coefficient adaptation is preferred with an electronic clutch management (EKM), with an automated one Manual gearbox (ASG), with a parallel gearbox (PSG) and / or with one use an uninterruptible manual transmission (USG).

Below is another possible embodiment of the present invention described in which a suitable distance measurement, in particular at Clutch actuators is proposed.

It has been shown that an incremental path measurement compared to a Absolute displacement sensor does not restrict a mechanically limited measuring range having. Accordingly, the present invention is based on the object preferably to suggest an absolute path measurement for clutch actuators, which does not have the aforementioned disadvantage.

Accordingly, for example, an absolute angle sensor, for example inductively, can be provided such that the entire display area is covered during one revolution, for example of the armature of the electrical clutch actuator. After one revolution, the sensor signal can then return to the initial state. This is shown in Fig. 2, for example.

In this way, an absolute path measurement, for example with a Absolute angle sensor can be provided without the disadvantage of a limited maximum path or a too low resolution of the sensor signal. Thus, by using an absolute angle sensor, a pure incremental distance measurement can be avoided.

In FIG. 2, a sensor signal for distance measurement is shown in a clutch actuator. The sensor signal corresponds to a counting absolute displacement measurement, as proposed by the embodiment of the present invention presented here.

A further embodiment of the present invention follows described in which an initialization of the position of the clutch actuator characteristic points preferably the clutch spring force characteristic is proposed.

It is possible for the position of the clutch actuator to be initialized by means of an incremental displacement measurement is carried out; this in particular to compensate mechanical changes to the respective coupling.

According to the invention it can be provided that instead of a stop or a Locking on the actuator or on the release system as a reference point at least one characteristic point of the force characteristic of the clutch spring is used to Example of a plate spring or the like.

For example, a kink or the like in the Force characteristic can be used. This kink occurs with a single clutch Example when the plate spring is relieved in such a way that the disengagement system from the disc spring. For example, with a combination clutch, in particular for an uninterruptible manual transmission (USG), a similar kink in that Course of the force characteristic curve, for example, with a middle position at the transition be provided between the two characteristics of the individual clutches. It is also possible that other reference points are used. For example force zero crossings can also be used as reference points.

Advantageously, it can be provided that the search and the determination such a reference point, a so-called software sniffing represents. Mechanical displacements such as those caused by wear or tear can occur can also occur due to thermal effects in the control of the actuator be balanced advantageously. On the other hand, through that Measuring the mechanical changes, for example when "sniffing", possibly also a conclusion about the thermal condition or the The degree of wear of the clutch can be pulled. It is essential that not the Reference point is determined exactly, but a method is to be specified, which reproducibly recognizes a position on the characteristic curve accordingly.

The following can be used to carry out the so-called software sniffing be taken into account; for the electric motor of the actuator, a change in the Release force as a change in the frictional torque in the almost self-locking Represent clutch release. This frictional torque can also depend on the sign of the external one Depend strength. Moving against the force results in a much larger one Friction as a movement in the direction of the force. Doing so may not be too small Forces an almost linear relationship between the force and the moment of friction result.

This so-called sniffing and position comparison can be carried out in different ways. For example, a speed measurement with a constant motor voltage can be provided. When the actuator moves with constant voltage, the speed results from the frictional torque that results from self-locking actuator gears. A change in the clutch spring force can cause a change in the friction torque and thus a change in the speed of the actuator. The measurement can preferably be carried out in one movement against the clutch spring force and with increasing spring constant (ΔF / Δx). The change in speed over the location (Δv / Δx) can be independent of the size of the speed if the inertia (≙ J> M _R ) is neglected. With almost linear force characteristics before and after the kink, the result is a value for Δv / Δx that is only dependent on the spring constant ((ΔF / Δx) and the motor properties.As the speed is the most accurate signal of the actuator for an incremental travel measurement, this speed change can easily measured and recognized in an advantageous manner.

FIG. 3 shows a possible load profile and a theoretical profile of the actuator speed resulting therefrom, the direction of movement of the actuator during the measurement being indicated by an arrow above the two diagrams. Faults that can occur periodically during the engine revolution are suppressed in the simplest way with this measuring method. It is only necessary that exactly one motor revolution is selected as the basis for the determination of Δv / Δx as Δx. For example, the reference point can then be determined by the intersection of speed ramps. It is also possible to use other reference points.

The speed measurement can initially only take place at the same angular position or phase position of the actuator, wherein x _i can be seen with i as an index for the motor revolution. From the speeds v _i determined in this way, it can then be recognized from which engine revolution the system is in the area of the hard spring. The following limit value results:

abs (v _i - v _i-1 )> limit

If it is recognized from which engine revolution the system is in the area of the hard spring, this means that the measurements of v _i and v _i-1 limit the first time interval from x _i to x _i-1 on the spring load. The measurements of v _i-2 and v _1-3 can limit the last time interval (x _i-2 to x _i-3 ) before the spring load. The position interval (x _i-1 to x _i-2 ) in which the reference point is provided can be located between these intervals.

The point at which the actuator speed changes can advantageously be determined from these intervals and the speeds measured at their limits. This corresponds to the reference point. This determination of the reference point is indicated graphically in FIG. 4, the position determined, that is to say the reference point, being indicated as an intersection between the two straight lines shown.

Any noise that may be present can be minimized by evaluating a measurement process with different phase positions with respect to the motor revolution and by subsequently averaging. A further possible improvement in the determination of the reference point can result from the fact that implausible results (if, for example, the reference position lies outside the interval x _i to x _i-3 ) are suppressed.

Also known problems, such as a wide spread of speeds certain phase positions can, according to a development of the present Invention taken into account in determining the reference point or in averaging become.

A possible algorithm is shown in a table in FIG. 5. It can be provided that a set of data is used for each phase position in which the reference position is sought. First of all, it is checked under the keyword “phase position” to which phase position the data belong. Under the keyword "revolution", a counter for the engine revolutions since the start of the measurement can be used, which serves to determine the position. A 4-value array can then be used under the keyword "Vbuffer", in which the last speeds are saved. Finally, the determined position can be output under the keyword "position", which is used for sequence control.

An overview of a possible flow chart is shown in FIG. 6. Initially, the process variables are initialized. Then the measurement and determination of the phase positions under consideration is started. The measurement is then continued with the determination of the reference points for the individual phase positions. Finally, the final results are determined by averaging the reference positions found for the individual phase positions. This is shown in FIG. 7 in a flowchart which includes the start of the measurement and the determination of the phase positions under consideration. In FIG. 8, a flow diagram is also shown, wherein the reference point is determined for the individual phase angles.

It is possible that the so-called "software sniffing" in the same Driving conditions is carried out in which the hydraulic sniffing is carried out becomes. Especially when the engine is stopped and while driving, if not is switched, this is possible. This ensures a regular comparison of the Position realized. Especially with an uninterruptible manual transmission (USG) this procedure corresponds to sniffing for the starting clutch, so that here you can sniff at the same driving conditions, if not with the power shift gear is driven.

This method, which is presented, can be used in particular in the case of electrical central disengagements or for the operation of a single or two coupled clutches be used. Overall, it can be said that this method is used in every actuator with mechanical release system as so-called "software sniffing" can be used, the type of displacement sensor used in the actuator system is irrelevant.

In addition, it is conceivable that this proposed initialization of the position of the actuator can also be used with mechanical end stops. For example, the position adjustment can also be carried out using a suitable one Touch point adaptation can be replaced or supplemented.

The so-called "software sniffing" is particularly advantageous with regard to the Searching for a reference point, particularly when driving long motorway journeys over long periods no touch point adaptation can be used as a replacement strategy.

The proposed position initialization is based on the following considerations:
The properties of permanently excited DC motors cause a speed to be set at a given voltage U that is linearly related to the braking torque.


in which
n: engine speed
n ₀ : idling speed
M _R : The frictional torque acting on the motor
M _A (U): Starting torque (torque when n = 0) The following applies: M _A (U) α U

Therefore, in a system in which the inertia of the motor has a negligible influence (≙J <M _R ), the load can be deduced from the speed of the motor. A position-dependent load thus leads to a position-dependent speed.

With a linear load curve, this also leads to a linear speed curve:

• - Keine integrierte Kompensationsfeder
• - Inkrementalwegsensor (aus einem Wählmotor) auf der Ankerwelle des Kupplungsaktors mit 40 Inkrementen pro Umdrehung; daraus folgt ca. 40 Inkremente pro mm am Geberzylinder; daraus folgt wiederum ca. 12,5 µm/Inkremente an der (theoretischen) Tellerfeder.

It can e.g. B. Measurements with a modified clutch actuator (ASG) can be carried out on a special test setup. The following modifications can be provided as possible modifications of the clutch actuator, the list not being exhaustive:

• - No integrated compensation spring
• - Incremental travel sensor (from a selector motor) on the armature shaft of the clutch actuator with 40 increments per revolution; this results in approx. 40 increments per mm on the master cylinder; this in turn results in approx. 12.5 µm / increments on the (theoretical) disc spring.

It can e.g. B. different loads (springs, detents, stops or combinations thereof) are given to the clutch actuator. The structure can preferably consist of a basic structure made of aluminum profile rails, to which the control unit is attached with the clutch actuator. Different load modules can be positioned on the aluminum profiles. The tappet of the clutch actuator is firmly connected to a rod that is slidably mounted over the basic structure. The locking profile and the stop washers (also for the springs) can be freely positioned on this rod and can also be detached. The positions of the different loads can thus be varied and several loads can also be used in combination. The test setup is shown schematically in FIG. 9.

• - Die (ehemalige) Kompensationsfeder mit 5.9 N/mm; sie dient der Simulation einer kleinen Last, wie sie auch im realen System benötigt wird, um ein sicheres Funktionieren des Ausrücksystems zu gewährleisten.
• - Die "Kupplungsfeder" mit 19.9 N/mm; sie simuliert die Kraft der Tellerfeder.

For the investigations presented here, two spring loads are used, whereby both springs are loaded in the same direction.

• - The (former) compensation spring with 5.9 N / mm; it is used to simulate a small load, as is also required in the real system, in order to ensure the safe functioning of the release system.
• - The "clutch spring" with 19.9 N / mm; it simulates the force of the disc spring.

With the test setup presented here, the load profile shown in FIG. 10 can be generated. The theoretical load profile includes the force profiles of springs 1 and 2 as well as the total profile. Due to the (almost) self-locking actuator gear, the position-dependent load results in a position-dependent (and movement-dependent) frictional torque on the motor. The friction torque for movements against the force is almost proportional to this force.

In the following, increments are preferably used for the position information. The conversion between increments and the true position is based on the Actuator gearbox only approximately linear. The sign also turns around. The weak spring begins in the measurements shown here a position of 0 increments (with increasing force with negative Position) and the strong spring starts at -100 increments. The motor voltages are specified via the pulse width ratio. A value of 255 corresponds to approx. 10 V. The speed in the control unit is preferred given values.

It can be seen that when using an incremental travel sensor, the actuator speed is the most accurate signal for the state of the actuator. A (externally attached) measurement of the motor current is also significantly less precise. First of all, the result of a series of measurements is to be shown here, with the actuator with different voltages (PWM ratios ± 30, ± 35, ± 40, ± 45, ± 50, ± 55 and ± 60) in both directions under the load shown above is driven. In Fig. 11 measured velocities are shown on the position voltages for different engine.

The effect of the load on the speed of the actuator is evident better for movements against the load (here at negative speeds) than with the load. This behavior can be seen from the properties of the explain self-locking gear. There is a clear disturbance with a period of 40 Increments = 1 motor revolution. When walking towards the load (under the periodic disturbance) a constant change in speed over the location (Δv / Δx) recognized regardless of the size of the speed. The reproducibility of the Measurements are very high.

The reproducibility of the speed measurements is shown in FIG . In this measurement, the actuator is moved eight times in both directions with the same voltage (PWM ratio = ± 35). The measurement curves agree very well. Even the small speed fluctuations with a period of 3 to 4 increments are reproducible. These are probably due to the magnetic armature locking. When evaluating the speed measurements, the calculation of the speed change per revolution is first taken into account. The first consideration is to calculate the difference in speed for exactly 40 increments in advance for each position, which is carried out according to the following equation:

B (x) = v (x) - v (x + 40) (for movements with negative speed.

Since the speed is not measured at every position due to the time sampling of the signals, the speed curve should be suitably interpolated. If the measurement data shown above are evaluated in this way, FIG. 13 results . Here too the movement takes place from right to left. The signal can be recognized by the noise but is so bad that it cannot be used for position adjustment in this form. The noise is advantageously reduced by averaging. However, the position resolution may deteriorate.

The calculation of the buckling position by linear interpolation of the speeds is considered below. If the speed is always observed at the same phase of the motor revolution (Pos mod 40 = const.) During a measurement, a signal can be released that is free from the modulation by the motor rotation. Depending on the phase position selected, a slightly different speed curve is shown here. Apart from some noise, the speed profiles only differ by a speed offset. In Fig. 14 this is illustrated for two phase positions.

Two speed profiles are shown with different phase positions. The next step for the evaluation is to recognize from which engine revolution you are on the hard spring. This is e.g. B. with a simple limit violation (| v _i - v _i-1 |> C). The limit value C can depend on the properties of the motor and the hardness of the spring. A rough position reference from the speed changes can be seen in FIG . This enables the kink position of the load characteristic to be found with an accuracy of ± 40 increments.

A better position can be obtained if the last speed measurements are used as support points for straight lines and their intersection is calculated. The measurements of v _i and v _i-1 limit the first interval on the hard spring, which is the position interval found above. The measurements of v _i-2 and v _i-3 limit the last interval before the hard spring. The determination of the exact reference position is shown graphically in FIG. 16.

The position determined in this way is still not very precise for each individual phase position (in the most favorable case to 20 increments); but it is possible to use this procedure for several phases of a series of measurements. However, a simple averaging of all possible positions that can be determined in this way is not sufficient to significantly improve the accuracy. Errors caused by noise can be partially recognized and suppressed. So it can happen that the determined intersection of the two straight lines outside the interval [x _i ; x _i-3 ]. Such a case can be easily recognized and the result for averaging can be suppressed.

It has also been shown that the speed determination for phase positions sit on the flanks of the periodic disturbance due to the interpolation very much is subject to large fluctuations. For this reason, therefore, is about to At the beginning of the measurement, be careful not to consider these phase positions. This is done by evaluating the acceleration (Δv / At). Phases that are in the limit the first engine revolution to excessive acceleration, will not considered further. The averaging from the values selected in this way for the The reference point determination then reaches the accuracy of approx. 10 to 12 Increments (or less than 5.5 increments of standard deviation).

The quality of the proposed method is tested by measurements with different starting positions for the hard spring. The specified positions are only approximate if they are set by hand. The reproducibility of the recognition of the same position is important here. This is shown in FIG. 17, with the determined positions of the reference point being indicated. Apart from the motor voltages being too small (<40) or too large (> 55), the position at which the kink of the force characteristic is found is independent of the motor voltage. The scatter of the determined positions is in a range of ± 3 to ± 5.5 increments. The individual measurements lasted between 35 (for U = -35) and 1.6 s (U = -55). If the measurements are limited to the necessary range of motion, measurement times between 1.6 s (U = -35) and 0.6 s (U = -55) are obtained. These can be reduced even further.

It can be assumed that the hardness of the spring whose starting position is sought goes into the accuracy of the position determination. But there is the possibility that a harder spring enables a more precise determination of the reference position. The influence of the voltage on the detected position should also be taken into account become. Furthermore, the effects of the starting position (relative to the reference point) and the measurement duration are taken into account. Since the actuator temperature in particular the Idling speed and the starting torque of the electric motor should also be influenced these are taken into account.

In summary, it can be stated that a method is proposed with which the actuator speed can be recognized, in particular for the Time at which the release system touches the plate spring. Particularly advantageous is that there are no additional sensors apart from the incremental displacement sensor or mechanical parts are required. This method can preferably be used Actuators without a compensation spring and with a mechanical release system (e.g. USG with EZA) can be used. The reproducibility achieved for the position comparison corresponds approximately to the standard deviation in the intended test. This would with this system a positioning accuracy of about 0.15 mm at the Correspond to disc spring.

A further embodiment of the invention presented here follows described in which a possible monitoring of an automated clutch is proposed in particular in the creep process.

Especially in the case of continuous crawling without vehicle movement, e.g. B. due an obstacle or on an incline, can occur at the slipping clutch high frictional energy, especially on the clutch disc. In order to this is associated with increased wear on the clutch linings. By warming or change the temperature gradients that develop in the clutch unit the transmission properties of the clutch. Maybe it is possible that there is a sharp increase in the transmitted from the clutch Moments can come. This can lead to undesirable vehicle movements and therefore associated safety-critical situations.

Accordingly, it can be provided according to the invention that for monitoring the Clutch when creep several monitoring methods are proposed which can be used alternatively or in combination.

For example, it is possible that the clutch temperature is preferably controlled using a Temperature sensor or a suitable model z. B. from the friction energy on the Clutch disc and cooling effects, such as speed-dependent Heat transfer and heat conduction is determined. Preferably, if exceeded a predetermined limit value activates the driver warning, d. H. the Driver can, for example, acoustically, optically and / or mechanically accordingly be warned.

It is also possible that the time duration is determined with the aid of a time measurement, in which a predetermined slip speed threshold when the creep condition is activated is exceeded. If preferably the time period is a predetermined limit driver warning can also be activated.

As part of another development, it can be provided that when activated Creep condition checks the engine torque and its time derivative or is observed. Suitable limit values can be defined for both quantities. Because the engine torque due to consumers, such as one Air conditioning or a power steering, can rise sharply for a short time, should Differentiation between the influence of consumers and temperature-related changes in Coupling transmission properties two limit conditions must be met. It other conditions are possible to distinguish between the to recognize different influences. If the engine torque exceeds specified limit value while the derivative remains below its limit value the driver warning and / or the adjustment of the Clutch transmission properties can be activated.

As an alternative to the aforementioned strategy, it can preferably also be provided that that with the help of a torque sensor, the one transmitted directly from the clutch Moment is determined. If this moment a predetermined limit exceeds the driver warning and / or the adjustment of the Clutch transmission properties can be activated.

Various options can be used as a driver warning alternatively or in combination with one another. It is conceivable that an acoustic warning, for example by a beeper or an announcement, is provided. Furthermore, a visual warning by a flashing Warning light or be provided by a text message in a display. About that There is also a mechanical warning, for example by jerking the Possible. The jerk can be caused, for example, by an oscillatory Movement of the clutch actuator can be caused. It should Main frequency band in the range of the vehicle's natural frequency, so that with small Moment amplitudes a clearly noticeable jerk is caused. Preferably can the bucking may be limited in time, for example for a few seconds, and / or with a certain time delay, for example 10 seconds, are repeated, so long until a driver reaction, for example by pressing the accelerator pedal or the Brake.

The software adaptation of the clutch transmission properties can principally done in two ways. For example by correcting the touch point and / or by correcting the coefficient of friction of the clutch characteristic.

However, in the monitoring method proposed according to the invention provided that the change in clutch transmission properties to the relevant clutch unit is analyzed, and the corresponding Procedure is preferably selected with appropriate weighting factors.

It is conceivable that the monitoring method according to the invention also is used when the clutch temperature when creeping over a first Limit increases. Then the torque transmitted by the clutch can be reduced become. Above a second limit, the clutch can be opened completely.

If the vehicle comes to a standstill on a slope with the clutch slipping should be held, opening the clutch leads to rolling back of the Vehicle. If the coupling temperature exceeds a limit value, the Depending on the gear, a warning jerk can be activated.

The monitoring method proposed according to the invention can be used for Gearbox concepts with automated clutch, especially for EKM, ASG, USG, PSG or the like are used, preferably when a creep function is integrated.

A further embodiment of the invention presented here follows described, in which a variable current limitation preferably one Coupling actuator for example for an XSG gearbox is proposed.

It has been shown that an optimization of the control of a clutch actuator in view of the different demands on dynamics and comfort is required.

A central requirement for the actuators of an automated clutch is u. a. a high dynamic; this means the shortest possible adjustment times. Around In known couplings, the actuator system has a high requirement Power requirement, which is relatively high in electromechanical actuations Streaming reflects. In this way, when starting electric motors Share very high currents (50 to 100 A) for a short time, if not suitable Measures to limit the current are provided. These high starting currents will however only accepted to a limited extent, since this impermissible electrical system loads and Impairments in comfort, such as flickering lights, noise from the controls or the like, can cause.

By changing the design of the electric motor, for example with regard to one higher resistance of the winding or the leads, higher currents be avoided. However, this can also increase the energy loss and on the other hand it can negatively affect the dynamics of the engine become. Accordingly, the limitation of the motor current is, for example fixed value more advantageous.

According to the invention, the maximum permissible motor current is provided Depending on the driving situation, in particular to let the control software vary. Thereby the dynamics can advantageously be increased in certain situations, while in other situations the load on the electrical system and the Loss of comfort for the driver can be avoided.

• - Der Fahrzeuggeschwindigkeit und/oder der Fahrzeugbeschleunigung; beispielsweise kann beim Ausrollen vor der Ampel bei niedriger Geschwindigkeit v und schwacher negativer Beschleunigung a der Maximalstrom I_max niedrig gewählt werden (zum Beispiel 30 A), da hier die Ansprüche des Fahrers an den Komfort größer als an die Dynamik sind.
• - Die Motordrehzahl; daraus folgt ein höherer Maximalstrom Imax bei höherer Motordrehzahl. Andererseits könnte unterhalb der Leerlaufdrehzahl ein höherer Maximalstrom I_max einen verbesserten Abwürgeschutz sicherstellen.
• - Die Fahrpedalstellung und/oder der Gradient der Fahrpedalstellung; eine hohe Fahrpedalstellung zeigt einen hohen Anspruch an Dynamik, daraus folgt ein hoher Maximalstrom I_max wobei höchste Dynamikanforderungen bei erkanntem Kickdown vorgesehen sind.
• - Die Wählhebelstellung bzw. der gewählte Fahrmodus; eine Anpassung des Maximalstromes I_max an den Fahrmodus, wie zum Beispiel Automatik, Tipp- Modus, Sport-Modus oder dergleichen, ist denkbar. Es können zum Beispiel während des Automatikmodus 40 A als Maximalstrom und zum Beispiel im Sportmodus 50 A als Maximalstrom gewählt werden.
• - Der Fahrertyp; bei einer vorhandenen Fahrererkennung oder bei einer Fahrererkennungsadaption kann einem sportlichen Fahrer ein höherer Maximalstrom Imax zugeordnet werden als zum Beispiel einem komfortorientierten Fahrer.
• - Der Ladezustand der Batterie; falls der Ladezustand von einem XSG- Steuergerät erfasst werden kann, beispielsweise über eine CAN-Verbindung zu einem Batteriemanagement-SG, könnte bei gut geladener Batterie ein höherer Maximalstrom I_max als zum Beispiel bei einer nahezu leeren Batterie eingestellt werden.
• - Die Temperatur, wie zum Beispiel Motortemperatur, Außenlufttemperatur, Getriebetemperatur, Aktortemperatur oder dergleichen; bei der Messung oder der Modulierung dieser Temperaturen ist eine Anpassung von dem Maximalstrom I_max möglich. Falls die Aktorik hohe Temperaturen aufweist, und eine zusätzliche Erwärmung vermieden werden soll, kann vorzugsweise der Maximalstrom I_max in Abhängigkeit zum Beispiel der Aktor- und/oder Getriebetemperatur entsprechend verringert werden.
• - Die Bremspedalstellung bzw. der Bremsdruck; es ist denkbar, dass zum Beispiel bei einer Vollbremsung zum Vermeiden des Abwürgens des Motors ein sehr hoher maximaler Strom I_max vorgesehen ist.
• - Die Fahrzeugsituation; bei einer für den Fahrer nachvollziehbaren Situation, wie zum Beispiel bei einer Schaltung oder dergleichen, kann ein höherer Maximalstrom I_max eingestellt werden, als in einer für den Fahrer nicht spürbaren Situation, wie zum Beispiel bei Adaptionen, Momentennachführungen oder dergleichen.

The possible influencing variables on the maximum current and the method for calculating the maximum current are specified below, the list of the possible influencing variables not being conclusive. The driving current-dependent maximum current I _max can depend on one or more of the following influencing variables:

• - The vehicle speed and / or the vehicle acceleration; For example, when coasting in front of the traffic lights at low speed v and weak negative acceleration a, the maximum current I _max low can be selected (for example 30 A), since the driver's demands for comfort are greater than for dynamics.
• - The engine speed; this results in a higher maximum current Imax at a higher motor speed. On the other hand, a higher maximum current I _max below the idling speed could ensure improved stall protection.
• - The accelerator pedal position and / or the gradient of the accelerator pedal position; A high accelerator pedal position shows a high demand for dynamics, which results in a high maximum current I _max, whereby the highest dynamic requirements are provided when kickdown is detected.
• - The selector lever position or the selected driving mode; an adaptation of the maximum current I _max to the driving mode, such as, for example, automatic, jog mode, sport mode or the like, is conceivable. For example, 40 A can be selected as the maximum current during the automatic mode and 50 A as the maximum current in the sport mode, for example.
• - The driver type; with existing driver identification or with a driver identification adaptation, a sporty driver can be assigned a higher maximum current Imax than, for example, a comfort-oriented driver.
• - The state of charge of the battery; If the state of charge can be detected by an XSG control unit, for example via a CAN connection to a battery management SG, a higher maximum current I _max could be set for a well-charged battery than, for example, for an almost empty battery.
• - The temperature, such as engine temperature, outside air temperature, gear temperature, actuator temperature or the like; when measuring or modulating these temperatures, an adaptation of the maximum current I _{max is} possible. If the actuator system has high temperatures and additional heating is to be avoided, the maximum current I _max can preferably be reduced accordingly depending on, for example, the actuator and / or transmission temperature.
• - The brake pedal position or the brake pressure; it is conceivable that a very high maximum current I _{max is} provided, for example, in the event of full braking in order to avoid the engine stalling.
• - The vehicle situation; in a situation that is understandable for the driver, for example in the case of a circuit or the like, a higher maximum current I _{max can be} set than in a situation that is not noticeable for the driver, such as in the case of adaptations, torque tracking or the like.

A further development of the present invention can provide that the time period during which the maximum current I _max can be set is preferably additionally limited. This is particularly advantageous for the use of an electrical central release.

• 1. Es ist möglich, dass in vorbestimmten Zeitabständen vorzugsweise etwa alle 10 ms die möglichen Einflussgrößen bzw. mindestens eine Einflussgröße ermittelt werden;
• 2. An Hand der verwendeten Einflussgrößen kann dann der Maximalstrom Imax in vorbestimmten Abständen ermittelt werden. Daraus ergibt sich eine Funktion I_max = f(Einflussgrößen);
• 3. Der Maximalstrom I_max kann an die Begrenzungseinheit ausgegeben werden. Dies kann zum Beispiel der Lageregler bei einer sogenannten Software (SW)-Realisierung oder der Stromregler bei einer sogenannten Hardware (HW)-Realisierung sein.

The current limitation according to the invention can be carried out, for example, by means of an analog current control, in which the setpoint is preferably predetermined by the control and the actual value is detected, for example, by means of suitable sensors, such as a Hall sensor or the like. It is also possible that a model-based limitation of the manipulated variable, for example the voltage, is implemented in the digital position controller. With model-based limitation, simultaneous online identification of the motor parameters can be advantageous. A possible expiration of the limitation can be provided as follows:

• 1. It is possible that the possible influencing variables or at least one influencing variable are determined at predetermined time intervals, preferably approximately every 10 ms;
• 2. Using the influencing variables used, the maximum current Imax can then be determined at predetermined intervals. This results in a function I _max = f (influencing variables);
• 3. The maximum current I _max can be output to the limiting unit. This can be, for example, the position controller with a so-called software (SW) implementation or the current controller with a so-called hardware (HW) implementation.

It is also conceivable that the limitation according to the invention expires other way is done.

When determining the maximum current I _max as a function of the influencing variables used, characteristic curves or two-dimensional characteristic diagrams can preferably be used. An example of a characteristic diagram for determining the maximum current I _max on the basis of the pedal value and the vehicle speed is shown in table form in FIG. 18. In the example shown, the maximum current I _max can be determined by linear interpolation between the influencing variables.

The following is a further possible embodiment of the invention presented here in which an increase in the reproducibility of the role cycle in a vehicle plant is proposed.

It is known that in the vehicle factory with an EKM or an ASG system Clutch is put into operation. Here u. a. the tactile point is determined and open an adjustment or setting of the Friction coefficient made. You can also use various parameters such as for example, the difference in clutch temperature before and after the role of Role cycle, the entry of riding energy into the clutch (model), and the correct one Commissioning of the coupling section or the like can be checked. This sets however, the test on the roll cycle assumes exactly reproducible Boundary conditions is driven.

In particular, the problem may arise that the role cycle is not in the kickdown Operation can be carried out because the 4-5 Upshift can not be driven and beyond a defined Pedal value setting below the "Kickdown" state in the vehicle factory on the Role cycle can not be adhered to.

Accordingly, it is the object of the present invention to develop a suitable strategy 4 for carrying out a reproducible role test.

Accordingly, it is provided in the present invention that during the Role tests a so-called adaptation acceleration is activated to a faster Cause convergence of the coefficient of friction adaptation. So long now Adaptation acceleration is activated, that provided by the transmission control Kickdown detection disabled, d. H. even if from an external control unit or A kickdown condition is signaled in the switch, the gearbox control unit Kickdown state cannot be recognized.

It is particularly advantageous with this strategy that the simplest possible Instructions for the test on the role cycle for the corresponding employees in the Vehicle factory can be given (for example, fully depress the pedal) and above In addition, there is simple reproducibility. It is also advantageous that the switching points are selected as for 100% full-load circuits can; thus the 4-5 upshift is still acceptable Speed range possible.

As part of a development of the present invention, it can be provided that that the role detection also to other suitable signals than that Adaptation acceleration is coupled; for example, an automatic Role recognition can be provided.

It is also possible that in addition to deactivating the kickdown signal, the Pedal value can be limited upwards. This is especially true if only small maximum speeds are possible on the reel, d. H. the 4-5 Upshifts should be shifted to lower speeds.

This strategy according to the invention can preferably be used in automated Manual transmissions (ASG systems) are used.

A further possible embodiment of the presented here is given below Invention described in which a correction of the engine torque is proposed to preferably achieve a convergence of the coefficient of friction adaptation.

In the case of EKM and ASG systems in particular, the coefficient of friction of the clutch and other influences can be adapted using the so-called coefficient of friction adaptation. at this adaptation can do that from the engine torque and the engine acceleration physical clutch torque are calculated and based on the deviation from The actual value of the engine torque is then adapted to the coefficient of friction. The adaptation can only be carried out in slip phases when starting and when shifting become. The accuracy of the engine torque has a great deal to do with the adaptation Influence. For technical reasons, the accuracy of the Motor torque is different when switching and when starting. As a consequence, that the coefficient of friction when shifting and when starting at different values converges.

The object of the present invention is to increase the engine torque in this way correct that the coefficient of friction is preferred when starting and shifting converges to the same values.

According to the invention it can be provided that the correction is carried out, for example, depending on the state, ie is carried out differently in the driving and starting states. The following equation can be used to perform the correction:

MMotKorr = MMot.Faktor

the factor can be determined using one of the following conditions or in any combination thereof. The corrected engine torque is denoted by MMotKorr and the engine torque is denoted by MMot.

As conditions such. B. be provided that the factor is constant. Further the factor can be a function of the pedal value, the engine speed, the Motor speed gradient, the gradient of the engine torque, the temperature at the Coupling, the temperature in the engine and / or a function of the engine running time. It is possible that other conditions are also provided, which then used individually or in combination with the other conditions can. With this procedure, the coefficient of friction adaptation can preferably be the corrected one Use engine torque.

This strategy can preferably be used to correct the engine torque in a electronic clutch management, in an automated transmission or the like can be applied.

Another possible embodiment of the invention is described below, in which a suitable continuous slip control, preferably depending on the Coupling load is proposed.

It is envisaged that with an EKM and an ASG control a so-called Permanent slip control is implemented. Here, the clutch can be specified by the path For example, ramp closed if the following conditions are for a certain time of usually 4 seconds is fulfilled.

A first condition can be that the transmission speed is greater than that Idle speed and the accelerator pedal is operated. If the accelerator pedal is very low is pressed, for example pedal value <10%, the ramp-shaped closing can the clutch cause the vehicle to slow down, so that the Transmission speed drops below idle speed. In this case the clutch should come back opened to avoid stalling the vehicle. This opening the Clutch can be very uncomfortable for the driver. It can also Vibration excitations.

Accordingly, an object of the invention is this jerk Avoid start-up vibrations in particular by means of a continuous slip control.

According to the invention this can be achieved by the conditions for the Activation of the continuous slip control can be suitably expanded or supplemented. It is by the term continuous slip control is to be understood as an ongoing slip on the clutch should be avoided to avoid damage or unnecessary Avoid heating the coupling.

At pedal values of around 10%, the clutch torque and the differential speed are however so low that there is hardly any heating and one Damage to the clutch can occur. In this case, the continuous slip control may be deactivated.

Accordingly, it is provided according to the invention that the continuous slip control only is activated if one or more of the following conditions are also met are.

A possible condition can be that the clutch temperature T _clutch should be greater than the limit value clutch temperature, ie the clutch temperature exceeds the limit value. It is also possible that the condition is that the clutch power loss is greater than a limit value of the clutch power loss, ie the clutch power loss exceeds a predetermined limit value. In addition, the condition can be that the pedal value is greater than a limit value of the pedal value, ie the pedal value should be greater than a predetermined limit value. Another condition can affect the clutch torque. The clutch torque should be greater than a limit value of the clutch torque. Finally, it can be provided that the engine torque is greater than a predetermined limit value of the engine torque. Other conditions are also possible under which the continuous slip control should be activated.

In this context, it is particularly useful to provide the query of the clutch performance as a condition. For example, the continuous slip control may only be activated if the clutch power loss P _{clutch is} greater than the limit value of the clutch power loss and the transmission speed is greater than the idle speed and the accelerator pedal is also actuated.

This strategy according to the invention for continuous slip control can preferably be used for electronic clutch management and automated manual transmission Systems are used.

A further embodiment of the invention is described below, in which a possible detection of a faulty clutch filling, preferably at Gear is suggested.

It has been shown that the clutch should be open, so that while running Engine can be engaged. At a service or at the end of the line The assembly plants may experience a serious problem during filling Error has occurred and the hydraulic line is not filled correctly. This Then it becomes apparent that it is not possible to get a while the engine is running engage synchronized gear. The maximum achievable position is at one synchronized gear the synchronized position. It is known that in such a If only the "Gear actuator" "Overtemperature" error is set, but only then, if the gear actuator has exceeded the limit temperature.

Accordingly, a strategy according to the invention is proposed, in which a Detection of a faulty clutch filling is provided. The can Gear engagement maximum position reached. If this is in the area synchronization, especially considering the switching elasticity, and the engine is on, an error code can be generated that points to the possible defect or incorrect filling in the hydraulic line the clutch indicates.

It is necessary to turn the motor to a speed difference between to manufacture the transmission input and the transmission output, thereby inserting the gear is not possible with the clutch closed.

It has been shown that the blocking behavior is similar even when the engine is stopped is to be expected, in particular by adhesive synchronizer rings, which the insertion prevent the passage. This is why you can avoid incorrect setting this error an engine speed may be present.

This strategy cannot be applied to non-synchronized gears because a tooth-tooth position is always to be expected for non-synchronized gears and thus the error can be erroneously set. To get around this, can For example, a suitable counter can be provided which only detects the error after Example of three unsuccessful gear changes.

The strategy according to the invention for identifying a faulty one Clutch filling can preferably be used in all automated gearboxes uninterruptible manual transmissions, in double clutch transmissions or the like be used.

A further embodiment of the invention presented here follows described, in which a possible emergency adaptation of the touch point preferably at Creep of the vehicle is suggested.

With the EKM / ASG software in the creep condition of the vehicle, it is possible to provide an emergency adaptation in which the software touch point is only corrected downwards under certain conditions. An important condition can be that the creep torque _builds up to a very high clutch torque within approx. 6 seconds (0.75 to 1.0 _{M creep_max} ). A too high target creep torque indicates that the software touch point is much too high. It can therefore make sense to reduce the touch point in this situation. A detection that the software touch point is too low, so that a touch point emergency adaptation in the direction of higher values is not provided in the known emergency adaptation.

Accordingly, it is proposed according to the invention that preferably when creeping secondary effects detect that the software touch point is too low, and that with it a touch point emergency adaptation in the direction of higher touch point values can be carried out. The following explains how the crawling strategy in the Clutch control works.

Before the creep begins, the engine torque can be determined for about 400 ms, and thus the average idling engine torque can be recorded. The creep torque build-up can then preferably take place in two stages in ramps with different slopes. The clutch _{setpoint torque} M _{RSoll is built up} as quickly as possible until the moment of momentum, and then the build-up is reduced. The creep torque build-up is shown by way of example in FIG. 19.

The engine torque can also be increased by increasing the clutch torque be increased because the idle controller tries to increase the idle speed LL speed hold. If the difference between the current engine torque and the Idle engine torque is greater than the nominal creep torque, for example approx. 10 Nm (depending on the vehicle), the target clutch torque cannot continue be built up, but it can be held. With that moment you can Creep can be made further. Since the actual clutch torque, with to which the vehicle is moved via the change in engine torque can be determined from the torque build-up, whether the software Touch point is too low.

• - Die Erkennung eines zu tiefen Software-Tastpunktes aufgrund der Höhe des Kriechmomentenaufbaus; wenn der Software-Tastpunkt zu tief ist, kann bei dem in Fig. 19 dargestellten Momentenaufbau das physikalische Kupplungsmoment sehr schnell aufgebaut werden. Dementsprechend erhöht sich auch das Motormoment relativ schnell. Somit kann dann die Differenz zwischen dem Motormoment und dem Leerlaufmotormoment das nominelle Kriechmoment früher als bei einem normalen Software-Tastpunkt übersteigen. Demzufolge und aufgrund der festgelegten Steigungen der Rampen wird das Kriechmoment bei einem sehr kleinen Kupplungsmoment, zum Beispiel bei ca. 5 Nm, eingefroren. Über die Differenz des aktuellen Kupplungsmomentes und des nominellen Kriechmomentes kann dann auf einen zu niedrigen Software- Tastpunkt zurückgerechnet werden, und der Software-Tastpunkt dementsprechend geeignet verändert werden.
• - Ebenso wie die Höhe des eingefrorenen Kupplungsmomentes kann auch die Zeit des Momentenaufbaus als Erkennung eines zu tiefen Software-Tastpunktes vorgesehen werden. Bei einem zu tiefen Software-Tastpunkt übersteigt die Differenz von Motormoment und Leerlaufmotormoment das nominellen Kriechmoment früher als bei einem normalen Software-Tastpunkt. Dementsprechend kann die Zeit, welche für den Aufbau erforderlich ist, als Maß des zu tiefen Software-Tastpunktes verwendet werden. Dabei bedeutet eine sehr kurze Aufbauzeit, dass der Software-Tastpunkt sehr tief ist.
• - Ein weiteres Indiz, dass der Software-Tastpunkt zu tief ist, kann der Einbruch der Motordrehzahl sein. Wenn das physikalische Kupplungsmoment beim Kriechen sehr schnell aufgebaut wird, welches bei einem zu tiefen Software- Tastpunkt der Fall ist, kann der Leerlaufsregler die Motordrehzahl meist nicht schnell genug wieder einregeln, so dass die Motordrehzahl n_Mot gesenkt wird. Wenn jedoch die Motordrehzahl unter eine bestimmte Grenze sinkt, kann davon ausgegangen werden, dass der Software-Tastpunkt viel zu tief ist. Somit kann diese Erkennung als Notadaption eines zu tiefen Software-Tastpunktes herangezogen werden. Allerdings sollte diese Erkennung auf den Leerlaufregler angepasst werden, da der Leerlaufregler bei verschiedenen Fahrzeugtypen unterschiedlich reagiert.
• - Eine weitere Möglichkeit liegt darin, dass bei einem zu tiefen Software- Tastpunkt mit einem daraus folgenden sehr schnellen Aufbau des physikalischen Kupplungsmomentes die Last für den Leerlaufregler sehr schnell ansteigt. Diese Last kann mit dem Leerlaufregler durch geeignete Algorithmen erkannt werden. Wenn diese Last sehr groß ist, und der Leerlaufregler von der Kupplungssteuerung die Information "Fahrzeug kriech" erhält, kann der Leerlaufregler die Information "Last ist sehr groß" zurücksenden, oder auch wenn es möglich ist, kann dieser einen Wert über die Höhe der Last angeben. Mit dieser Information kann dann der Software-Tastpunkt entsprechend erhöhte werden.
• - Eine weitere mögliche Ausgestaltung kann vorsehen, dass die Fahrzeugbeschleunigung für die Erkennung eines zu tiefen Software-Tastpunktes herangezogen wird. Wenn das physikalische Kupplungsmoment aufgrund eines zu tiefen Software-Tastpunktes sehr schnell aufgebaut wird, kann auch das Fahrzeug sehr schnell beschleunigt werden. Somit kann der Software-Tastpunkt erhöht werden, wenn die Fahrzeugbeschleunigung einen bestimmten Wert überschreitet. Wenn die Fahrzeugbeschleunigung nicht gemessen wird, kann diese aus der Rad- oder der Tachodrehzahl sowie der Drehzahl der Getriebeeingangs- oder Getriebeausgangswelle durch Ableitung ermittelt werden. Dabei ist jedoch zu beachten, dass die Fahrzeugbeschleunigung nur bedingt für die genannte Erkennung geeignet ist, da z. B. beim Ankriechen an einem steilen Berg ebenfalls starke Fahrzeugbeschleunigungen entstehen können. Hierzu ist dann entweder eine Bergabrollerkennung notwendig oder die Fahrzeugbeschleunigung sollte als zusätzliche Erkennung zu den anderen genannten Erkennungen vorgesehen sein.

There are preferably the following detection options:

• - The detection of a software touch point that is too low due to the height of the creep torque build-up; If the software touch point is too low, the physical clutch torque can be built up very quickly with the torque build-up shown in FIG. 19. Accordingly, the engine torque increases relatively quickly. The difference between the engine torque and the idling engine torque can then exceed the nominal creep torque earlier than at a normal software touch point. As a result, and due to the specified slopes of the ramps, the creep torque is frozen at a very small clutch torque, for example at approx. 5 Nm. The difference between the current clutch torque and the nominal creep torque can then be used to calculate back to a software touch point that is too low, and the software touch point can be changed accordingly.
• - Just like the level of the frozen clutch torque, the time of the torque build-up can be provided as a detection of a software touch point that is too low. If the software touch point is too low, the difference between engine torque and idling engine torque exceeds the nominal creep torque earlier than with a normal software touch point. Accordingly, the time required for the set-up can be used as a measure of the software touch point which is too low. A very short set-up time means that the software touch point is very low.
• - Another indication that the software touch point is too low can be the drop in engine speed. If the physical clutch torque is creeping up very quickly when creeping, which is the case when the software touch point is too low, the idle controller cannot regulate the engine speed quickly enough, so that the engine speed n _{Mot is} reduced. However, if the engine speed drops below a certain limit, it can be assumed that the software touch point is far too low. This detection can thus be used as an emergency adaptation of a software touch point that is too low. However, this detection should be adapted to the idle controller, since the idle controller reacts differently for different vehicle types.
• - Another possibility is that if the software touch point is too low with a consequent very fast build-up of the physical clutch torque, the load for the idle controller increases very quickly. This load can be identified with the idle controller using suitable algorithms. If this load is very large and the idle controller receives the information "vehicle creep" from the clutch control, the idle controller can send back the information "load is very large" or, if possible, it can give a value about the amount of the load specify. With this information, the software touch point can then be increased accordingly.
• A further possible embodiment can provide that the vehicle acceleration is used for the detection of a software touch point that is too deep. If the physical clutch torque builds up very quickly due to a software touch point that is too low, the vehicle can also be accelerated very quickly. Thus, the software touch point can be increased if the vehicle acceleration exceeds a certain value. If the vehicle acceleration is not measured, it can be derived from the wheel or tachometer speed and the speed of the transmission input or transmission output shaft. It should be noted, however, that vehicle acceleration is only suitable to a limited extent for the above-mentioned recognition. B. strong vehicle accelerations can also arise when crawling on a steep mountain. For this purpose, either a hill roll detection is necessary or the vehicle acceleration should be provided as an additional detection in addition to the other detections mentioned.

The way of increasing the software tactile point can be done in different ways and Way are provided. The proposed emergency adaptation of the touch point In particular, in the creep condition of the vehicle, the adaptation can advantageously design precise and very robust. The adaptation according to the invention can all vehicles with automatic clutch can be used.

A further possible embodiment of the presented here is given below Invention described in which a tactile point determination preferably at the end of the tape a vehicle plant is provided.

It is possible that the tactile point determination at the end of the tape, in particular without Test device. According to the invention in the manufacture of a ASG or an EKM control unit with certain operating parameters Standard values are used. Among other things, the touch point can have a value be described outside the tolerance range. A tactile point determination in Work without a test device requirement can only take place if the Touch point is out of range. The test can then be carried out in the control unit be performed. It has also shown that there is one bit for each key point determination should be present. If a tactile point determination is successful, it can corresponding bits are set. The next touch point determination can only then be carried out if the previous one was successful. Thus, it becomes more advantageous Way ensures that all three touch point determinations are in the correct Order.

In particular, it is normally only possible to drive on the roll of the manufacturing plant at the end of the line and under no circumstances apply the hand brake. For this reason, the handbrake can advantageously be used as a signal for determining the tactile point. This enables volume equalization and touch point determination to be carried out if the conditions specified as examples are met:
Handbrake applied; serves as the actual start signal
Foot brake applied;
with an ASG system, the selector lever should be in the "N" or "D"position;
if this is in the "D" position, the gear should be designed;
with an EKM system, the shift lever should be in "N";
the idle switch should be pressed;
Vehicle stands, that is, the transmission speed is at the value "zero";
previous touch point determination should be successful, which can be recognized by the bit.

If these conditions are preferably met, a can first Volume equalization and proceed to a next step become. However, it should be noted that the third touch point determination only at the end the role is performed. To carry out a further plausibility check, it makes sense to start the third investigation only when the Vehicle speed greater than a predetermined limit, for example 100 km / h or the like. In this way it can be ensured that the third Touch point determination, which represents a fine adjustment, is provided at the end.

If the aforementioned conditions are met, it can be provided that a Gear is engaged. With an ASG system with selector lever in position "D" can this is done automatically. With an EKM system or with an ASG system, at the selector lever is in the "N" position, the driver should be aware of this be made that the first gear is now engaged. This can be done either an optical signal, such as the gear indicator flashing in the vehicle display, or by an acoustic signal, such as beeping with a certain Beep sequence can be provided.

The next step is to determine the tactile point. If the result of the Touch point determination is within the tolerance range, the bit for the touch point determination be set. After correctly determining the tactile point, a can preferably be used appropriate signal can be given and the second touch point determination can then respectively. For example, the signal can be a visual signal, which is characterized by Flashing appears in the display. If the second touch point determination is negative, or has not yet ended, a signal may appear on the display. The driver can about the result of the tactile point determination, for example by a blinking of the Gear indicator can be informed on the display.

When determining the tactile point according to the invention, the aforementioned steps can be carried out can be combined with each other at will, and it is also possible that more Steps can be combined with these. In this way, a Touch point determination can be carried out without diagnosis.

A further possible embodiment of the presented here is given below Described invention, in which a strategy is proposed, which a starting with an automated manual transmission without clutch as an emergency run at one Coupling actuator failure enabled.

In a vehicle, the clutch, also called the starting clutch, is used for Alignment of the speed between the motor shaft and the transmission input shaft by one Starting off or switching. When starting, the Coupling the separation of the engine from the drive train when the engine is idling or when Vehicle standstill, the coupling between the engine and the powertrain during of the starting process (clutch slips) and the coupling of the motor the drive train after starting (usually the clutch is liable) enable. Accordingly, the engine torque is not at all (at complete open clutch), partially (with sliding clutch) or completely (with clutch) from the engine to the wheels. The energy loss caused by the Difference between the engine and transmission input shaft speed at sliding clutch is created, is converted into heat in the clutch.

In vehicles with an automated manual transmission, the actuation of the Coupling carried out by the clutch actuator by means of an electric motor. If the Clutch actuator has failed, the clutch is always closed, so that Starting is no longer possible.

A specially modified automated manual transmission (ASG3) has one Synchronization with which it is possible to start in an emergency in the event of a clutch actuator failure is. According to the invention, it can then be provided that the separation and the Coupling of the engine from or to the drive train by two devices on Drivetrain is performed. Preferably, through the clutch and Synchronizer in the transmission this can be provided. In this way, the Clutch replaced by synchronization in the event of a clutch actuator failure if the synchronization is designed for high energy loss.

With an automated manual transmission (ASG) is the synchronization usually only designed for small energy losses. Therefore, the task is based the speed synchronization of the transmission output shaft against the transmission input shaft provided. The energy lost during the Synchronization process arises, only the kinetic energy of the transmission input shaft open clutch.

Synchronization in an automated manual transmission can also Powershift clutch are called, which for the circuits without Traction interruption are designed. This is the speed synchronization of the Gearbox output shaft against the gearbox input shaft, however, when the gearbox is closed or sliding start clutch. This means that the energy loss occurs during synchronization, not just the kinetic energy of the Transmission input shafts due to their inertia, but also the drive energy from Motor must take up. Accordingly, the synchronizations are one automated manual transmission designed for high performance.

As a result, the synchronization of an automated manual transmission fulfills all of them Conditions that a normal clutch should have when starting. Due to this is the start-up as emergency operation with synchronization in the event of Clutch actuator failure possible in an advantageous manner.

A further possible embodiment of the presented here is given below Invention described in which a strategy to avoid accidental Closing the clutch is suggested in the event of a fault.

When using a screw actuator as a clutch actuator, such as a electrically operated central release (EZA), a mechanically operated central release (MZA) or the like, can in the event of failure of the release bearing or the Blocking, an unintentional and spontaneous closing of the clutch, which then possible uncontrolled rotations of the helical gear unit of the Screw actuator cannot be ruled out.

Accordingly, a correlation of the direction of rotation of the Internal combustion engine and the direction of the slope of the screw gear unit Screw actuators depending on the type of coupling used to avoid this an unintentional closing of the clutch in the event of a fault. Especially when using screw actuators with the release bearing connected disc springs (LAC, Push-Pull) it can be in any position of the Releasers come to failure of the release bearing. As a result, it can then become Blocking the clutch actuator come because the screw gear unit of the Screw actuator by the plate spring or ultimately by the internal combustion engine driven and set in uncontrolled rotation. Even if Fastening elements of the screw actuator are finally torn off by the Screw-nut principle of the releaser actuated, which in the worst case one unintentional and uncontrolled closing of the clutch can result.

In order to avoid this in an advantageous manner, it can be proposed that the Direction of rotation of the motor, the direction of the helical gear unit Screw actuator and / or the coupling type have to correlate so that in the case of the failure of the release bearing, the actuator is operated such that the clutch does not close, but is opened.

The screw actuator is shown schematically in FIG. 20, the situation being shown when the release bearing is blocking.

Below is another possible embodiment of the present invention described, in which a height start aid preferably from the Coupling temperature is affected.

In ASG and EKM controls, a so-called height start aid (HAH) is implemented. If the pedal value is above a high limit, for example 75%, and the vehicle does not move within a certain time with the gear engaged, the clutch can be opened slightly to move the engine speed to a range in which the engine is more Can deliver moment. The clutch can then be fully closed again when the engine speed is greater than a predetermined threshold and the vehicle is moved and a predetermined time t _{1 has} passed. If the vehicle is still not at a predetermined time, for example t ₂ = 6 s, or the engine speed is still less than a predetermined threshold, the clutch can still be closed quickly in order to avoid continuous slippage. However, a start-up attempt is not possible as a result.

Accordingly, it can be provided in the present invention that the start-up aid is modified in such a way that a start-up process is nevertheless possible under all circumstances. It is conceivable that the time threshold at which the clutch is closed or engaged is appropriately increased. In the above example, this would mean that the time t ₂ would have to be increased. If, for example, the time t _{2 is raised} to a value which is greater than 6 s, there is the possibility that the starting process is ended. However, there is also a risk that the coupling can be damaged by an excessively high coupling temperature.

In order to solve this problem as well, the time threshold t ₂ can only be increased if the clutch temperature is less than a predetermined limit value of, for example, approximately 250 ° C. In this way, the clutch is not damaged in an advantageous manner and the starting process can. U. still be finished.

A further embodiment of the present invention follows described in which a suitable structure of the creep torque in the event of fluctuations in Engine torque is proposed, which improves its comfort becomes.

In Fig. 21, a measurement is represented in different graphs which indicate the construction of the creeping torque in multiple steps due to the collapse of the engine torque. This creep torque build-up is uncomfortable for the driver, because it is crucial in a creep torque build-up that the clutch torque is built up continuously so that the vehicle acceleration is approximately uniform. The cause of the creep torque build-up shown in FIG. 21 lies in the fluctuations in the engine torque. The creep torque strategy in the clutch control can provide that the engine torque is averaged for about 400 ms before creeping (M _{Mot_Filt} ). When the creep begins, the creep torque can be built up slowly, then faster, but always with a constant slope, depending on the vehicle, with a constant ramp gradient. If the difference between the current engine torque M _{Mot_aktuell} and the averaged engine torque M _{Mot_Filt exceeds} a fixed nominal creep _torque M _{Kriech_nom} , the creep _torque build-up can be ended and the creep _torque can be kept constant. If, for example, as shown in FIG. 21, vibrations are generated in the course of the engine torque, for example by a poorly tuned idling controller, the torque build-up can be stopped if the above-mentioned condition is fulfilled. If the difference between the current engine torque and the averaged engine torque falls below the threshold of the fixed nominal creep torque, the creep torque can be further developed according to the known strategy. This process can last a maximum of 6 s, after which the creep torque can be frozen. With this creep torque build-up in several stages, the driver can perceive the vehicle acceleration as two thrusts when crawling. The vehicle crawls off and suddenly there is an acceleration for a short time; then the vehicle continues to crawl. This is uncomfortable for the driver.

Accordingly, it is proposed according to the invention that the structure of the Creep torque is modified appropriately to these vehicle accelerations avoid, and thus make the creep torque build-up more comfortable for the driver.

Within the scope of a further development of the present invention, it is possible for the gradient of the current engine torque M _{Mot_aktuell to} be observed in the creep torque build-up according to the invention. If the gradient course is normal, the clutch control expects a steadily increasing gradient. However, if the gradient of the current engine torque is negative or falls below a threshold to be determined, the engine torque can advantageously be frozen immediately if the difference between the current engine torque and the average engine torque is greater than the fixed nominal creep torque. After that, this can no longer change in the current creep process. This creep torque structure according to the invention is shown in FIG. 22. The courses of the old target clutch torque curve and the new target clutch torque curve over time are shown.

It is also possible that the idle controller tends to vibrate strongly, and the condition that the difference between the current engine torque and the averaged engine torque is greater than the nominal creep torque is met so quickly that only a very small creep torque is built up, as a result of which the vehicle is insufficiently moved. In this case it can be provided that the gradient of the engine torque is also observed. If the gradient of the current engine torque is negative or falls below a threshold to be determined after the aforementioned condition was met, it can be provided according to the invention that the desired clutch torque is built up more slowly but steadily. This speed when building up the clutch setpoint torque can then be maintained even if the current engine torque becomes a second time smaller and the creep torque would be built up further in the current strategy. This procedure is indicated in FIG. 23, where the old and the new course of the desired clutch torque over time are shown again.

As a further variant, it can be provided that the build-up speed is selected in order to be able to switch back to the normal build-up speed when the current engine torque drops, whereby the difference from the situation in the current creep strategy is that the creep torque build-up according to the invention does not stop , but slowly increases, so that the acceleration differences are very small. This is indicated in FIG. 24, the differences of the different gradients in the new course of the desired clutch torque not being chosen too large.

With this option, due to the continuously increasing creep torque, termination conditions for the further build-up of the creep torque must be defined so that the creep torque is not built up too high. The following conditions can be provided as termination conditions, suitable combinations of these or other conditions also being possible:
Termination of the increasing creep torque at a predetermined maximum creep torque;
Termination after a predetermined time;
Abort when the vehicle acceleration exceeds a predetermined value;
Abort if synchronization between engine speed and gearbox speed has been reached.

Other termination conditions are also possible, which may then be combined with the conditions already mentioned can be combined appropriately.

A further strategy for building up the creep torque can provide that the gradient of the current engine torque is observed and if the condition that the difference between the current engine torque and the mean engine torque is greater than the nominal creep torque is fulfilled at least once and the gradient of the current one Engine torque is negative or falls below a threshold to be determined, the creep torque can only be built up very slowly from this point in time, so that the driver can barely perceive the change in acceleration in an advantageous manner. This is indicated in Fig. 25 by the new and the old course of the clutch target torque.

These strategies are presented to build up the creep torque basically in all vehicles with automatic clutch and with one Torque strategy applicable for creep torque build-up.

A further embodiment of the invention presented here follows described in which a suitable limitation of the clutch target torque preferably suggested when closing the clutch for the jerk function becomes.

The jerk function of the clutch control is a driver warning if a driver wants to start in a gear that is too high, for example gear 3 , 4 or 5 . It has been shown that when the clutch is closed, the engine can turn away. The cause may be that the clutch torque is limited to the level of the engine torque due to the risk of stalling. Using the closing function, the clutch can be closed further from the current clutch torque, in particular via a path control at approximately 0.5 mm / s, up to the maximum clutch torque. This means that the higher torque is always set. Accordingly, the clutch torque is at a maximum value depending on the torque control and the displacement control. By tightening, a slight overpressure can be given, which increases over time. If the software coefficient of friction is incorrectly too high, it may happen that the overpressure is too low due to the path control, and thus the motor drives away.

• 1. Wartezeit bis zum Ruckeln;
• 2. Ruckelrampen durchführen;
• 3. Zuziehen der Kupplung, wobei die Kupplung über die Wegsteuerung mit etwa 0,5 mm/s zugezogen werden kann.

In this case, the clutch torque is modulated in such a way that the driver experiences a strong change in acceleration and is thus advised to shift back into first gear. The jerk function can consist of three phases, for example:

• 1. Waiting time before jerking;
• 2. Carry out bucking ramps;
• 3. Pull the clutch closed, whereby the clutch can be pulled in at about 0.5 mm / s via the path control.

According to the invention, the situation is first recognized that the engine is touring. This is the case if the engine has a specified engine speed or when the slip exceeds a limit to be determined. Likewise, the Engine speed are strongly filtered or averaged during bucking (phase 2) and this speed will be saved. If the engine speed at To close (phase 3) this stored speed exceeds or this Speed with an offset to be determined, a touring of the Motors are recognized.

A possible reaction to this situation can be that the limitation of the clutch torque is increased depending on the engine speed. This can be achieved with a factor that is set using the following map.

Limitation = factor

A possible map is shown in Fig. 26. The factor is shown over the engine speed.

It is also possible that instead of the engine speed, the slip speed is used between the engine and the transmission. Otherwise, as with the the above-mentioned embodiment can be moved.

Another variant can provide that the energy introduced into the Clutch or the power converted at the clutch is recorded. With these recorded quantities can then be an overpressure factor with the help of a similar one Map are built and then can continue as in the aforementioned Refinements are made.

Another way to modify the clutch limit Target torque can provide that after the detection of the tour of the Motor preferably the clutch is pulled much faster. This For example, the closing speed can be constant. It is also possible that the closing speed also depends on the engine speed and / or Slip can depend. It is possible that the energy introduced into the Clutch is detected and the closing speed depending on this Suitable energy and / or depending on the power implemented on the coupling is changed.

The aforementioned configurations can also be suitably combined with one another to prevent the motor from unintentionally turning away. The The proposed strategy can preferably be used with all vehicles automatic clutch and with a provided jerk function, i.e. with one EKM, ASG, USG, PSG or the like system can be used.

A further embodiment of the present invention follows described in which an improved torque build-up after a gear change is proposed.

With a possible strategy for the torque build-up after a gear change it can happen that the transferable moment of the still slipping Clutch exceeds the moment that the clutch shortly afterwards transfers when it is liable. This means that vehicle acceleration during of the re-engagement can become larger than immediately afterwards. This Increased acceleration can be uncomfortable for the occupants of the vehicle and feel comfort-reducing.

Accordingly, it is desirable that the acceleration of Allow zero to the target acceleration without local extremes.

• - Das Motormoment kann linear von einem Anfangswert auf das Fahrerwunschmoment gebracht werden. Der Anfangswert hängt dabei vom Gang und der Gaspedalstellung ab;
• - Parallel dazu kann das Kupplungsmoment T_cl erhöht werden. Dabei bleibt es um einen gewissen Betrag ΔT über dem Motormoment. Dieser Betrag nimmt mit abnehmendem Schlupf ab.

A possible torque build-up after a gear change, such as that implemented in an automated manual transmission (ASG), essentially works as follows:

• - The engine torque can be brought linearly from an initial value to the driver's desired torque. The initial value depends on the gear and the accelerator pedal position;
• - In parallel, the clutch torque T _{cl can be} increased. It remains a certain amount ΔT above the engine torque. This amount decreases with decreasing slip.

This possible strategy can cause unnecessary loss of comfort. For example, at the beginning of the moment build-up, the slip is very large. It follows that the ΔT is greater than zero and thus also greater than the clutch torque T _cl . The torque transmitted by the clutch does not increase steadily, but abruptly. This in turn can stimulate vibrations in the drive train, which can have a noticeable impact on comfort.

Furthermore, it can happen that the clutch torque T _{cl increases} during the slip phase above this value, which the adhesive clutch later transmits. In such a case, a higher moment is transmitted to the wheels shortly before the transition from slipping to sticking than afterwards. This means that the vehicle acceleration is excessive, which can be noticed by the driver in a manner that reduces comfort.

Accordingly, according to the present invention, the physical behavior of the drive train is described by a simple model, which is indicated in FIG. 27. The motor has the moment of inertia J _e and can deliver the adjustable torque T _e , which is the torque of the internal combustion engine. The speed of rotation of the motor is ω _e . The clutch can transmit a torque whose amount is less than or equal to T _cl . If the clutch slips, this amount is exactly equal to T _cl ; if the clutch is stuck, this is at most T _cl . The transmissible torque of the clutch T _cl is adjustable. A ratio i is provided between the clutch and the vehicle. The speed of rotation of the left side of the gear ratio, _i.e. the transmission _input shaft, is _denoted by ω _gbi . The vehicle has the moment of inertia J _v . From the outside, the vehicle is affected by the driving resistance T _r , which is composed of the rolling resistance, the air resistance and the downhill force.

The strategy according to the invention can e.g. B. be carried out as follows. The clutch torque can preferably be brought linearly from 0 to that torque T _cl2 which transmits the clutch immediately after the transition to sticking. At the same time, the engine torque can be controlled in such a way that the slip is reduced precisely when the clutch _torque reaches the value T _cl2 and / or the engine torque again corresponds to the driver's desired torque from this point in time.

If the engine torque cannot be controlled precisely enough to Implementing the proposed strategy can include: B. the engine speed additionally can still be regulated by modulating the clutch torque. It should however, make sure that the clutch torque during the Reconnection increases monotonously. This type of tax strategy is one so-called pilot control.

The torque T _cl2 can be calculated in the proposed strategy using the following equation 1:


where T _{e, d is} the engine torque requested by the driver. To be able to solve the right side of equation 1, T _r must be known. When the clutch is stuck, the equations of motion for the engine and the vehicle are:




where T * | cl is the torque transmitted by the clutch. Eliminating this quantity from equations 2 and 3 and solving for T _r leads to equation 4:

T _r can be calculated from this equation, where ≙ _{e is} determined by the numerical derivative of ω _e .

In the strategy _{according to the} invention, the clutch torque is increased linearly from 0 to T _cl2 during the torque _buildup :

T _cl = st Eq. 5

where s is the rate of moment build-up. The duration τ results from:

The further steps and requirements of the strategy can be formulated as follows:

ω _e (τ) = ω _gbi (τ) Eq. 7

T _e (τ) = T _{e, d} (τ) Eq. 8th

where T _{e, d} (τ) is the driver's desired torque at the end of the torque _build-up . The assumption is made here that this is approximately constant; from this follows T _{e, d} (τ) = T _{e, d} (τ) = T _{e, d} . The rotation speeds of the left and right sides of equation 7 can be determined by integrating equations of motion 2 and 3:


where T _r does not change significantly in the period under consideration, ie does not depend on t. The right side of Equation 9 can be solved by substituting the equations for T _cl (t).

With equations 8 and 9 two conditions are connected to the time course of T _e . For T _e (t), an arbitrary approach can now be chosen, which depends on exactly two parameters a and b still to be determined. A time course can preferably be selected in which t occurs up to the second power. In addition, it can be demanded that T _e is constant at t = 0:

T _e (t) = T _e (0) + at + bt ² Eq. 11

The right side of equation 11 is inserted into the left side of equation 8 and solved for a:

The right sides of Equations 5, 10 and 11 are inserted into Equation 9, integrated and solved for b:

Accordingly, the clutch and engine torque can be adjusted using the Appropriately control equations 5 and 11. The contained in the equations Quantities can be evaluated by consecutively evaluating equations 4, 1, 10, 13 and 12 be determined.

As already mentioned, it was assumed that the driver's desired torque and the driving resistance remained approximately constant during the re-engagement. However, this does not necessarily have to be assumed. The current values of these variables are continuously accessible to the control code. In this way, the target torque T _{cl2 of} the clutch, which is required for calculating the current clutch _torque according to equation 5, can be adapted for each interrupt in accordance with the changed values of T _{e, d} and T _r . The same can be done with parameters a and b, which are used to calculate the engine torque. However, in the event of a change in T _{e, d} and / or T _r, it is to be expected that the clutch slip will not be reduced exactly at the expected time τ, but before or after it. This then results in the jerk in vehicle acceleration, which is however so small that it does not have a comfort-reducing effect. However, the change in T _r is so small that the air resistance, the rolling resistance and the slope angle of the road do not change noticeably during the short re-engagement phase.

In Fig. 27a is a flow chart of the proposed strategy is shown, and the procedure can be invoked preferably once per clock cycle.

A further embodiment of the present invention follows described in which a suitable voltage control for pulling the Clutch under slip is proposed.

When closing the clutch, it can, for example, with a so-called slow path ramp under slip that occur, for example, when the driver the continuous slip control detects at least one jerk. The jerk can result from small jumps in the clutch torque curve. If the Clutch can be closed slowly by means of the specified path, due to the Switch-off hysteresis in the clutch position control at the actual value stepped course arise. This jerk is uncomfortable for the driver and should therefore be prevented.

Accordingly, it is provided according to the invention that for closing the clutch preferably under tension instead of the position control, a voltage control is provided.

It is possible that the turn-off hysteresis in the above was reduced mentioned situations is provided. When using the clutch actuator Usually very strong locking moments are provided. The Switch-off hysteresis is introduced based on these cogging moments. If so Switch-off hysteresis for the above situation is reduced, it is possible that by locking the electric motor a similar behavior as in the course of the stairs is provided with large switch-off hysteresis. However is this course is less pronounced and the flanks are less pronounced Incline. This leads to a significant reduction in the torque jumps so that these are no longer used by the driver in an advantageous manner be perceived. In this way, the comfort when closing the clutch for raised the driver.

It is also possible that according to an advantageous development, that the clutch position control is switched to voltage control becomes. If in these situations where the clutch is in the slip phase a path control is closed, a constant voltage curve is provided, a largely continuous course of the actual position can be made possible become.

However, there can be two restrictions; because the one used Clutch actuator has the above-mentioned strong locking moments. If the clutch actuator is operated with a very low voltage, these locking moments can ensure that the actual position is not continuous, but also runs in small steps. However, these levels are in advantageously not as pronounced as with the switch-off hysteresis. According to one Further training can be provided that a minimum voltage is set, which should not be undercut in order not to exceed the intended levels to be let.

Another limitation may be that the clutch actuator ever after using the clutch at constant voltage due to the different disengagement force of the clutches can move at different speeds. Around To avoid this, the invention provides that the A suitable change in the actual position is observed. If the change is too fast takes place, the voltage can be reduced accordingly, and if the If the change is too slow, the voltage can be increased accordingly. Further it can be provided that the required voltage is learned by for example when starting the parking lock when switching the clutch actuator, which is done, for example, by path control, the voltage curve recorded and a medium voltage is stored. It is also possible that instead a record of other possible ways of communicating the Voltage can be provided. The learned voltage can then on the appropriate ramp slope can be converted and thus any Slope of the ramp of a path control adapted to the respective clutch become.

It can be provided that the shortly before the zero point Voltage control is switched back to the position control so that the clutch actuator cannot drive against the stop. The position of the switchover can for example depending on the slope of the ramps. Because the switchover If a clutch is provided at almost full torque, this can be assumed be that the slip is reduced, and again by the position control momentary stairs not created by the driver be perceived.

This strategy according to the invention when closing the clutch can be used all vehicles with a clutch control can be provided.

A further embodiment of the present invention follows described, in which a suitable coefficient of friction adaptation, preferably at high Coupling temperatures and coupling temperature gradients is proposed.

The physical actuating torque characteristic can be set to a nominal value in the software Characteristic curve are mapped. The software Friction coefficient, also called SW-RW. The software coefficient of friction can be used when starting up and circuits are adapted. With the software coefficient of friction and its Adaption can be short-term and long-term changes in physical Torque characteristics are detected and adapted to the software. A factor that the physical moment can change greatly in the short term is the physical one Coefficient of friction. This is strongly temperature-dependent. The physical coefficient of friction increases with the temperature and drops sharply at a surface-specific temperature. This is also known as fading.

It can happen that the lining temperature at the clutch to Example for many mountain drives in a row, and thus the software coefficient of friction changed very quickly. It has been shown that the software coefficient of friction adaptation is sometimes adapted too slowly and this leads to very long hatching phases Approaches and circuits can come. Due to the long hatching phases the clutch can be heated up even faster, so that the physical Friction coefficient changed even faster.

Accordingly, it can be provided according to the invention that the coefficient of friction adaptation accelerate high clutch temperatures, so the fast Changes in the physical coefficient of friction are absorbed by the software can.

When adjusting the coefficient of friction, this can be done in the clutch control during slip phases determined actual clutch torque can be compared with the physical value. The physical torque is the engine torque and the Engine acceleration determined. If the two moments have different values, the software coefficient of friction should preferably be changed in small steps. For example, preferably a maximum of 15 increments per circuit or each Directions can be used. The maximum change can be chosen that sufficient robustness of the friction coefficient adaptation is guaranteed. Around accelerate the coefficient of friction adaptation so that rapid changes in the physical coefficient of friction can be adjusted are different options conceivable.

It is possible that when a predetermined clutch temperature is reached and / or the maximum when a predetermined temperature gradient is reached Value of the increments used is increased with a predetermined value.

Furthermore, it is conceivable that when a predetermined one is reached Coupling temperature and / or when a predetermined temperature gradient is reached maximum value of the increments used, preferably linear with the Coupling temperature is increased.

It is also possible that the maximum increment in a map, which for example the clutch temperature and / or the temperature gradient is determined, so that at higher temperatures and / or higher Temperature gradients the coefficient of friction can be changed more quickly.

The measures mentioned ensure that in normal Working area in which the clutch is located most of the time, the coefficient of friction adaptation is sufficiently robust, but in an area in which the coefficient of friction can greatly change the adaptation speed in an advantageous manner is adjusted.

The proposed coefficient of friction adaptation can be used in particular with ASG, EKM, PSG, USG systems or the like are used.

Below is another possible embodiment of the present invention described, in which a touch point correction preferably using the Coupling temperature is proposed.

Especially with an electronic clutch management (EKM) or with an automated manual transmission (ASG) with hydraulic control of the Coupling can cause displacements of the touch point due to Changes in temperature can be compensated for by regular sniffing. If as a result of Driving maneuvers, such as crawling continuously or stop and go, none so-called sniffing is possible, this can be done by a medium-term adaptation of the Touch point be balanced. The next sniff, which one This change can be made at the latest when the vehicle is switched off of the medium-term touch point can be withdrawn by the touch point is reset to the long-term value. By sniffing at Parking the vehicle can also compensate for displacements of the touch point so that when the ignition is switched on again from a defined, balanced system can be assumed.

When using a system without a hydraulic route, such as at the electrically operated central release (EZA), this comparison is with The ignition cannot be switched off. Accordingly, according to the invention be provided that the current clutch temperature when switching off the ignition is also saved, especially if the behavior of the clutch between the temperature and the displacement of the touch point is known. At the Switching on the ignition can then correspond to the current gripping point Temperature when saving is corrected. As a connection between the clutch temperature and the gripping point shift can be in the control unit preferably any mathematical function can be stored.

Another possibility according to the invention can provide that the physical torque characteristic curve of the clutch to that stored in the software nominal actuating torque characteristic is mapped.

The working range of the torque characteristic curve, that is, the distance between the touch point and the maximum torque of the clutch is also temperature dependent. This working area can be used while driving preferably via the tactile point adaptation and the coefficient of friction adaptation or more generally can be precisely determined using a characteristic curve adaptation. Furthermore, it is Changes in the working range known via the temperature of the clutch. If this behavior is not well known, it can occur during the Driving operations are started accordingly. For example, at Hand of the touch point and the coefficient of friction as well as the location of the Torque maximums are provided.

If the vehicle is parked with a warm clutch, the Information about the coupling temperature and the behavior of the working area via the clutch temperature when switching on the ignition with cold Coupling the position can be determined relative to the locking point. As a context between the coupling temperature and the change in the working range the clutch can preferably be any in the control unit mathematical function.

Since the location of the touch point is known, all the necessary information is Working range of the clutch together with the coefficient of friction known to the physical torque characteristic curve of the clutch to that in the software to map the stored nominal torque characteristic.

The proposed touch point correction can be used in particular for everyone electrical central release for an EKM, ASG, USG, PSG system or the like are used.

A further embodiment of the present invention follows described in which a suitable rough positioning of a clutch actuator Incremental path measurement is proposed.

Especially with an uninterruptible manual transmission with a central release (USG-EZA) only one incremental travel sensor is provided.

This means that only relative movements of the actuator can be recorded. So it can Provide situations in which nothing is known about the position of the actuator, e.g. B. at commissioning or at the end of the line.

Accordingly, a possibility is to be found with which at least a rough one Information (± 1 mm) about the current actuator position can be obtained without the there is a risk of closing the actuator against a mechanical stop drive that the self-locking gearbox is stuck afterwards.

One way to get information about the current position of a clutch actuator received, represents the measurement of the engagement and disengagement force Properties of the self-locking gear (spring band gear) used. Consequently the load (engagement / disengagement force) is a friction torque in the actuator motor Spring band gearbox.

The relationship between the load on the actuator and the friction torque in the Spring band gear is used in which the speed of the actuator is below the constant motor voltage is evaluated. As for the first position reference no large movements are possible (unknown position of the stops) this method is unsuitable here.

• 1. Einem echten lastabhängigen Reibmoment im Federbandgetriebe (richtungsunabhängig); und
• 2. dem aus der Last übersetzten Moment (richtungsabhängig).

However, the frictional torque in the spring band gearbox also depends on the sign of the torque (or the movement) of the actuator motor. This friction torque consists of at least two components:

• 1. A real load-dependent friction torque in the spring band gear (regardless of direction); and
• 2. The moment translated from the load (depending on the direction).

Since the gearbox is self-locking, the load torque can never exceed the moment of friction. Overall, one of the (intended) Frictional torque dependent on the direction of movement (Mr + and Mr-), the difference between the Values for the two directions corresponds to twice the load torque, i.e. is proportional to the load.

FIG. 28 shows the theoretical relationship between the external force and the frictional torque on the self-locking transmission of the uninterruptible manual transmission (USG), where Mr + denotes movement against the load and Mr-: movement against the load.

In addition to the possibility of defined short voltage / current surges Trigger movement of the actuator and evaluate its width (or in extreme cases to find the force equilibrium position by "trembling"), the frictional moments also about those required for starting in the respective direction of the actuator Tensions can be roughly determined. The latter has the advantage that the so obtained Measurement results proportional to the load torque, i.e. also proportional to the external one Are strength.

When the motor is stopped, a voltage leads to a current and proportional to it thus also to a motor torque proportional to this voltage. electrical Voltages are in this system via a pulsed full voltage (12 V) reached. The effective output voltage is determined by the ratio "voltage set to "to" voltage off "; this is called pulse width modulation (PWM).

For the force measurement, the motor voltage is slowly increased until movement of the actuator is detected. The actuator starts to move when the motor torque M _M α I α U becomes larger than the friction torque Mr. This is done in both directions so that Mr + and Mr- can be measured. The difference between the minimum required voltages then gives a measure of the external force on the actuator.

A single force measurement is shown in FIG. 29, the actuator position at the top and the output voltage at the bottom being indicated as a PWM ratio.

In the force measurement shown in FIG. 29, the upward movement requires a greater voltage (approx. A PWM of 32) than the downward movement (approx. 22). This difference now gives a statement about the external force. The small motor voltages applied after the voltage ramps, which counteract the movement, serve to brake the actuator motor. This voltage is so low (PWM = 6) that it cannot maintain or even trigger any movement of the actuator by itself.

A possible flow of a force measurement is shown in a flow chart in FIG. 30. As can also be seen, the movement is not recognized immediately by a change in position by an increment. The interaction between the anchor locking and the positions at which the increments are recognized requires at least one movement to wait for two increments. However, a limit of four increments further reduces uncertainty. This measurement is not very accurate. If a large number of measurements are carried out, however, the force curve can be recognized. In Fig. 31 the results of 10 measurements are collected, in which at each of the same 21 positions the force is measured. The curve of the disengagement or engagement force is illustrated with the solid line. The coordinate system for the position is set in these measurements in order to achieve the goal of the complete position reference.

In Fig. 31 the results of the force measurements are shown on the coupling system. In addition, the position areas used for rough positioning are already marked.

• a) Werte unter -3 sind nur im stark negativen Bereich (< -4 mm) zu finden;
• b) Im Bereich zwischen -4 mm und 0 mm treten nur kleine Messwerte zwischen -3 und +3 auf;
• c) Werte über +3 sind nur bei positiven Positionen zu finden;
• d) Werte über +10 sind nur bei Positionen oberhalb von +1,5 mm zu finden.

When evaluating the measurements for rough positioning, the strong scatter in the measurement results is clearly shown. Nevertheless, a rough conclusion about the position can be drawn from the measurement results. The areas (a) to (d) in Fig. 31 are explained below.

• a) Values below -3 can only be found in the strongly negative range (<-4 mm);
• b) In the range between -4 mm and 0 mm, only small measured values between -3 and +3 occur;
• c) Values above +3 can only be found in positive positions;
• d) Values above +10 can only be found at positions above +1.5 mm.

These results can be used to roughly position the actuator become. In this the actuator gropes through the system until it Detects transition from negative to positive position values. There is one Compromise between the speed and accuracy of this positioning too Find. The low accuracy of the force measurement allows only a rough one Approach the reference position. Only when the measured values are clearly large can a Larger position step can be performed to determine the duration of the rough positioning to keep low.

FIG. 32 shows a flow chart in which the limit values are given in the same way as they are e.g. B. are implemented in the uninterruptible manual transmission (USG). This procedure finds a position slightly (approx. 1 mm) above the reference position. However, this can be compensated for by a position correction at the end of the rough positioning.

Examples of the rough positioning process are given below.

A series of measurements are carried out to check the rough positioning. A rough positioning was started at different positions in the adjusted state (reference position at position 0). A measurement of a rough positioning with start at -6 mm is shown graphically in FIG. 33. By resetting the incremental travel sensor, the movements always start at position 0 mm and then move in the direction of the negative start position. The actual force measurement process can be seen in the paired forward and backward movements of the actuator.

In Fig. 34 a measurement of a coarse positioning with start at +6 mm is shown graphically. The measurements shown here are extreme cases. The closer the starting position of the reference run is to the reference point, the fewer steps are required to find it.

Because of the noise in the force measurement, the courses are at different rough positions from the same start position differently. In rare Cases (less than 1 in 25 in these exams) also result in noise to an incorrect detection of the position. In these cases the following works Not fine positioning. But that can be recognized by the software on what a new rough positioning is started.

Overall, this rough positioning procedure is quite robust. It can preferably in three different pairs of clutch and EZA be used if the force characteristic of the Clutches is changed (flatter increase in force towards positive Positions), the rough positioning works unchanged.

It is conceivable that the actuator can lift more than 1 mm from the plate spring. This force-free millimeter can be found with this rough positioning. In addition, the fine positioning also has sufficient travel reserves.

This method can be used advantageously for push-pull couplings. Here occurs clear difference between positive and negative clutch force; moreover the proportion with characteristic disengagement forces increases by about one Millimeter. The reference point search procedure used must be used can of course be adapted to the conditions of the respective coupling system.

Overall, with the described embodiment of the present invention Method specified, in particular in the case of a USG clutch actuator unknown position carries out a grave determination of its reference position can be used without using a mechanical stop. This The method according to the invention can be used in particular for a basic initialization as used for Example used at the end of the tape can be applied. It is about a rough measurement of the disengagement or engagement force over the minimum voltage for Movements of the actuator motor are provided. The reference position can initially be approximately ± 0.5 mm can be determined. Then, by means of a suitable fine adjustment Reference position can be determined exactly. This method according to the invention can can also be used for other coupling systems.

In the method according to the invention, additional elements, such as force sensors in the system, can be dispensed with. This is particularly because the actuator motor itself is used to determine the position. For this purpose, the motor voltage of the actuator motor can be increased twice with opposite signs in a time ramp until the movement of the actuator is determined or a maximum voltage is reached. The difference between the two voltages at which the motor begins to move is, apart from the noise, proportional to the disengagement or engagement force. The flow of an individual force measurement is shown in a flowchart in FIG. 35. To save time in the process, the voltage ramps can not be zero, but z. B. can be started at a predetermined starting value.

To interactions of the magnetic anchor detents and the location of the To minimize position increments, the movement of the actuator can only at a Minimum number of position increments are recognized, which are preferably greater than 1 is. For example, the limit can be 4. The brake voltage is U_Brems chosen so small that the actuator does not move in the same direction stops or can even cause the actuator to start up.

It has been shown that although this force measurement has a strong noise is subject to sufficient information about the current position of the actuator become. The force curve in the clutch system should be sufficiently structured. It large portions of approx. <1/6 of the range of motion with clear Force levels exist. In addition to an area with very, is particularly advantageous here small load a change of sign of the load. From this it can be decided which position change is to be carried out next in order to obtain more information about the to obtain the absolute position of the actuator.

A further embodiment of the invention presented here follows described, in which a plausibility check of the actuator position preferably at Switching on the control unit without using stops is proposed.

For clutch actuators with incremental displacement measurement, such as the EZA, there may be a problem that when the control unit is switched on it is not certain where the clutch is located. There are ways to change the position of the controller Turn off the control unit to save so that when the Control unit can be moved from this position. However, this requires that during the time the control unit is switched off, no change in the Actuator position has been made. This requirement does not exist if, for example, the clutch actuator has been opened and the actuator position has been changed by hand.

It is possible to always be in the "ignition on" phase in the above situation first approach the stop in the direction of "close clutch" so that Reference point for the physical coordinate system of the coupling is given.

According to the invention it can be provided that the stop for the plausibility check the position is not required. This should be in the EKM / ASG control specified procedure from the zero position (parking lock) to the HUB position, i.e. via the entire working range of the clutch control can be changed in such a way that a plausibility check is provided at the same time as to whether a gross change the zero position in the "ignition off" phase. Provided is going to limit the working range of the clutch control Zero point and stroke from the last phase "ignition on" is known.

When the control unit is switched on, the actuator can, for example, be in the parking lock position (corresponds to the zero point of the working range of the clutch control). This is the starting position of the travel path. A short distance is traveled in the direction of “closing clutch” (delta_HUB), as is also shown by the arrows arranged below the diagram in FIG. 36. A maximum speed to be determined is not exceeded. If the actuator is still in the same position that corresponds to that when the control unit was switched off, the actuator cannot hit a stop with this method. Accordingly, the travel distance should be selected accordingly.

A comparison of the physical coordinate system of the clutch and the coordinate system of the clutch control is indicated in FIG. 36, the suggested travel path of the actuator for plausibility checking of the emergency position being indicated by the arrows arranged below the diagram.

Then the actuator can be moved to the HUB + delta_HUB position, as in the Neutral gear of the starter is operated. This procedure should only work with one limited speed, as it is possible that against the stop is driven, especially if the actuator position in the "ignition off" state has been adjusted. If the actuator is switched on when the ignition is switched on Position stood, as when switching off the ignition, which is the normal case characterized, the actuator is not moved against the stop. As a result delta HUB can be selected accordingly. Then you can go to the HUB position be started and the normal driving mode is available. Overall, the time will be Procedure not significantly extended.

A prerequisite for the method according to the invention is that the distances the zero point drift and the distance between the stop and the HUB position all tolerances of the hardware are greater than the travel distances delta_NP and delta- HUB.

Another advantage of the method according to the invention is that more information be obtained, in particular on the location of the attacks.

A further development of the method according to the invention is that during appropriate opening of the clutch in the "ignition on" state Monitoring takes place to see whether a stop has been hit. That way, on the procedure in the other direction can be omitted (delta_NP and delta_Hub are zero). This training has the advantage that the paths below the zero point and above the HUB position have to.

Overall, it can be stated that in the method according to the invention for Plausibility check of the actuator position can be provided that if Appropriate ways are available, it is checked in both directions whether stops can be approached. It can further be provided that if there are no paths are available or if the search takes too long, is opened by touch.

Possible errors can e.g. B. an emergency opening, an improper Coupling replacement, a reset by undervoltage or a reset by ISM. A comparison If an error is detected, it can provide that the stops for the Plausibility check can be used.

A further embodiment of the present invention follows described in which a switchable freewheel is proposed as a load torque lock.

Especially with self-locking gears with an efficiency of over 50% it was found that the resulting coefficient of friction is often too high, so that there is a second-order self-locking.

In the case of existing self-locking, it can then only be operated against it be, whereby no actuation can take place in the direction of the load. This Behavior corresponds to a classic freewheel, i.e. H. a load torque lock, the Rotational movement in only one device is possible. The self-locking is in essentially provided by two gears, which are inside, outside, oblique or can be designed with arrow teeth. In addition, the training is with parallel, crossed and / or intersected axes possible.

The behavior described above cannot be restricted to one direction only. This is shown in particular in FIG. 37. Thus, when a directed moment 2 is applied to the gear of the locking member 3, the direction of the freewheel or self-locking can be determined. The moment can be applied in all conceivable forms, for example magnetically, mechanically, electromechanically, piezomechanically or the like. Another advantage here is that low outputs are required for the changeover and activation.

The inhibiting drive described above enables by not applying the moment a normal drive train without self-locking. The so-called Freewheel clamp can be integrated in any position of a transmission power train.

In this way, by using an originally undesired effect, namely second-order self-locking in a self-locking gear with an efficiency of over 50%, a suitable freewheel through an escapement gear intended.

This freewheel according to the invention can be used, for example, in starters, starters Generator drives, foot crank starters, actuators, clutch adjustments or the like are used.

A further embodiment of the invention is described below, in which at least one suitable cage to ensure the functionality of Ramp mechanisms with rolling elements is proposed.

There are various ramp release systems with rolling elements, e.g. B. balls in a mechanically actuated central release (MZA). Because of not Existing positive restraint can be after vibrations of the Entire system or after a large number of short movements to one The rolling elements move away from the target position. Due to the special shape of the Ramps themselves can then lead to malfunctions. For example a stiffness or a shortening of the stroke length possible.

The functioning of a mechanically actuated central release (MZA) is based on a wedge effect between two rotating parts with corresponding ramps. Rolling elements are preferably used at the contact points. A wedge gear of the MZA with rolling elements is shown in Fig. 38, with a contact point being developed on the plane. A possible basic structure of an MZA is indicated in FIG. 39.

The above-mentioned problem is represented graphically by FIGS. 40 and 41. In Fig. 40 different states of motion of the rolling elements between the ramps are indicated, with a) showing the ramp mechanism in the starting position and b) the ramp mechanism in the lifting position (actuated). In c) a blocking of the ramp mechanism by the rolling elements is indicated, which represents a disadvantageous shortening of the stroke.

A modified ramp shape is shown in FIG. 41. The changed ramps = shape (without stop) or the absence of a cage between the rolling elements cannot solve the aforementioned problem.

According to the invention, it can be provided that there are preferably several on each ramp Rolling elements are provided. The rolling elements can preferably be in one suitable cage. In this way, the aforementioned disadvantages avoided.

The shape of the openings in the cage, which are preferably as axial slots or The like are formed, can advantageously the distance between the rolling elements hold in the direction of advance. However, the rolling elements move in the stroke direction possible. The rolling elements can thus adjust the distance between the ramp tracks adjust appropriately. Because the distance between the rolling elements is preferably less than theirs Roll path, it can be ensured that there is always at least one rolling element lies between the respective ramps. If the ramps continue to be none Have path limitation, the cage u. U. hike as far as you want. Even if a If the rolling elements move, the function is not negatively affected.

In Fig. 42, the ramp mechanism is shown with the inventive cage, wherein the maximum lift position indicated in a) the starting position and in b). It is particularly advantageous that the stroke can be generated in both actuation directions if the ramp is designed accordingly. This property can be used to achieve a longer lifespan for the ramp mechanism.

The claim submitted with the application is a proposal for formulation without prejudice for obtaining further patent protection. The applicant reserves the right to do more, so far only in the description and / or in the Drawings combinations of features disclosed.

The exemplary embodiments are not to be understood as a limitation of the invention. Rather, there are numerous changes within the scope of the present disclosure and modifications possible, in particular such variants, elements and Combinations and / or materials, for example, by combination or modification by individuals in conjunction with those in the general description and Embodiments and the claims described and in the drawings contained characteristics or elements or process steps for the expert in With regard to the solution of the task are removable and by combinable Characteristics of a new item or new process steps or Process step sequences lead, also as far as they manufacturing, testing and working procedures affect.

Claims (1)

Method, device and its use for operating a motor vehicle, with a drive motor, a clutch and / or and a transmission in the drive train, in particular for controlling the transmission, characterized by at least one of the following features contained in the application documents or the combination of at least two of these Characteristics.