DE10106419A1 - Gear change device for automatic discrete gearbox has change gate crossing selection gate - Google Patents

Abstract

The device has at least one change element (12) movable in two dimensions, first and/or second actuators for the first and/or second dimensions and a change device operated by moving the change element along a selection gate with lateral change gates. A change gate crosses the selection gate so that movement of the change element in one direction in the change gate selects first gear and in the opposite direction selects reverse gear.

Description

The invention relates to a device for switching an automated Gear shift transmission according to the preamble of claim 1, and of the Proverbs 2.

Automated gear shift transmissions are becoming common in modern motor vehicles taking used. Such transmissions largely offer comfort tional automatic transmission, for example, work with converter clutch the planetary gear. Compared to these gears have automated Manual transmission has the advantage of lower consumption and lower costs. Of conventional gearboxes can also be automated by using a Switching element of such a transmission with the necessary actuators and one electronic control to control these actuators.

An important boundary condition for such automated manual transmissions is one reliable gear detection and absolute confusion between Forward and reverse gear, since such a mix-up is naturally fatal Can have consequences.  

Fig. 6 shows an example of essential elements of the actuation of a manual transmission. The manual transmission, not shown, has shift forks 2 , which, via guides connected to them, in guides 4 fixed to the transmission housing, bring shift rods 6 into engagement and disengage the gearwheels of the transmission assigned to the individual gears. To actuate the shift fork 2 , a shift element designated overall by 8 is used, which has a shift shaft 10 , from which a shift finger 12 projects, which engages in the recess of the shift forks 2 , which are U-shaped overall.

The selector shaft 10 has two lugs 14 and 16 , the lug 14 is provided with a toothing running perpendicular to the axis of the selector shaft 10 and the lug 16 has an axially parallel toothing. A pinion of an electric motor 18 or 20 meshes with the teeth of the lugs 14 and 16 . The electric motors 18 and 20 are connected to a control unit 22 which has inputs 24 , to which relevant signals are supplied for the operation of the transmission and a coupling, not shown, which is also actuated by an electric motor, for example. One of the inputs 24 is connected to an accelerator pedal 26 which indicates the driver's performance request. The structure and function of such a control or actuation device are known per se and are therefore not explained. When the selector shaft 10 is moved in the vertical direction (double arrow W) by the electric motor 18 , the shift finger 12 moves from one shift fork to the other or in a selector gate, whereas when the selector shaft 10 (double arrow S) is rotated, the respective shift fork for switching a corridor is shifted.

Fig. 7 shows a typical circuit diagram. There are four switch alleys SG, which start from a selector gate WG. The acc. Fig. 7 left shift gate only serves to shift the reverse gear R; the subsequent shift gate is used to shift the first and second forward gears etc. Because the first gear normally used as the starting gear and the reverse gear lie side by side and shifted in the same direction, there is a risk that the position will not be detected with absolute certainty of the shift finger 12 within the selector gate WG is accidentally switched to the reverse gear and not to the first gear or vice versa. Naturally, this can have serious consequences when starting from a standstill.

The invention has for its object a generic device to further develop that a high security against a verse usual shift or confusion of the first gear with the back forward gear is achieved. The invention is further based on the object Training device of the type that a comfortable circuit in the first Gear or reverse gear is possible.  

This object is achieved with the features of claim 1 and claims 2. The fact that, according to the invention, the first gear and the reverse gear lie in a common shift gate, the circuit can be made very safe by very simple measures in the drive for the movement of the switching element in the direction of a shift gate. For example, the drive can be reversed, starting from the switching element located in the selector gate in a shift in one or the other direction of a shift gate, this reversal being secured in the control unit by appropriate algorithms. Effects of failures of sensors to detect the position of the switching element (not shown in FIG. 6) or of misalignments or counting errors with regard to the position of stepping motors are largely eliminated in this way. The drive must not, as shown in Fig. 6, be electrical, but can be made hy, hydraulic, pneumatic, electromagnetic or otherwise.

The feature of claim 3 discloses an advantageous embodiment.

With the feature of claim 4, such a drive can be converted in a particularly simple manner by an electric motor, for example the electric motor 20 according to FIG. Fig. 6, starting from a central position of the switching element in the selector gate in one direction of a selector gate with one polarity and in the other direction of the selector gate with the other polarity is operated.

A drive in hydraulic, pneumatic or electromotive type may be provided.

With the features of claim 6, the advantage is achieved that an drive out of the second gear or an accidental engagement of the second gear is secured.

Claim 7 and claim 8 are each based on an embodiment of the inventions device directed with which a "scratching" of the transmission ver is prevented if due to a stationary vehicle and clutch open of friction in the clutch transmission, the input shaft of the Transmission does not come to a complete stop.

Claims 9 to 13 relate to advantageous embodiments of the brake direction according to claim 7 or claim 8 directed.

With the features of claim 14, additional protection is ge achieved against inadvertent shifting into a starting gear.

The invention further relates to a device for braking the input shaft of a manual transmission, in particular an automated manual transmission bes of a vehicle.  

Automated manual transmissions (ASG) are increasingly used in modern vehicles Motor vehicles. Compared to conventional automatic transmissions with tarpaulin sets and torque converters work, they have the advantage less Consumption and lower cost. The one with automated gearboxes The driving comfort achieved is the same as that achieved with conventional automatic transmissions Comfort not after.

If one equipped with such an automated manual transmission For example, if the vehicle brakes, the vehicle's clutch becomes auto actuated and opened at the latest when the internal combustion engine with Idling speed is running. If the transmission is also in neutral, like Neutral position, is switched, the input shaft is neither with the crankshaft the internal combustion engine is still coupled to the output shaft of the transmission and can rotate freely. Due to the inertia of the clutch clutch disc The input shaft may take several seconds to develop eventually comes to a standstill due to bearing friction. In some In some cases, the clutch does not open completely, leaving a remainder torque keeps the input shaft at the speed of the crankshaft.

So that the first gear or the reverse gear or another starting gear The input shaft must be inserted when the vehicle is stationary stand still so that there are no uncomfortable scratching noises or loading  Damage to the claw coupling is coming. This is known to the Zahnrä those of the first gear and reverse gear lock synchronizations To be attached to the input speeds before engaging the gear synchronize shaft and output shaft. Such synchronizations are required space and cause costs.

The invention has for its object to remedy the aforementioned problem to create, that is, to create a manual transmission that without locking synchro Synchronizations or synchronizations at least of the starting gears gets along.

This object is achieved with the feature of claim 15.

According to the manual transmission is equipped with a braking device stet, which brakes the input shaft as soon as its speed a predetermined falls below th value.

The subclaims relate to advantageous embodiments and further training directed towards the device according to the invention.

The invention is illustrated below with the aid of schematic drawings exemplified and explained in more detail. Put in the drawings represents:

Fig. 1 is a circuit diagram according to the invention,

Fig. 2 is a flowchart for explaining the flow of a Anfahrvor gear,

Fig. 3 is a circuit diagram indicating the location of a brake activation,

Fig. 4 is a comparison with FIG. 3 modified circuit diagram,

Fig. 5 shows a braking device,

Fig. 6 is a diagram of a confirmation means,

Fig. 7 is a known per se circuit diagram,

Fig. 8 seinrichtung a partial section through a first embodiment of a Brem;

Fig. 9 is a partial section through a modified embodiment of a brake device,

Fig. 10 characteristics to explain the operation of the Bremseinrich device and

Fig. 11 is a schematic of a known automated Schaltge transmission.

Fig. 1 shows a device according to the invention in the actuating device already described. Fig. 6 used circuit diagram. As can be seen, the first gear and the reverse gear lie in a common shift gate SG. In addition to the Fig. 1 left shift gate, in which the first gear and the reverse gear lie, there is a second shift gate, in which the second gear is arranged next to the first gear.

With this arrangement, in which the two main starting gears are in a common shift gate, it is possible to determine which of the two gears can be shifted only by the polarity with which the electric motor, which determines the movement of the shift element in the direction of a shift gate is. If the shift finger 12 acc. Fig. 6 in the neutral position, ie located in the selector gate, the first gear can only be switched when the electric motor 16 is operated with a voltage of one polarity, whereas the reverse gear can only be switched when the electric motor 16 with the opposite polarity is operated. A shift in the second gear, in which the switching element is moved in the direction of a selector gate in the same direction as when switching the first gear, is accordingly safeguarded, so that an accidental shift in the second gear, which in example in a winter program as Approach gear can be used is secured.

As shown in Fig. 1, further switching gates (dashed) can be provided.

With the design or assignment of the shift gates according to the invention compared to conventional arrangements, a significant gain in safety accidentally started in an unintentional gear.

Fig. 2 shows a flow chart of a starting process. The beginning process begins with it being determined in step 40 that the vehicle is stationary. In step 42 it is then determined whether the vehicle should start driving in the forward or reverse direction. The driver signals this by operating a corresponding selector lever. If the determination is not clear, the algorithm returns and repeats step 42 . If it is clearly determined in which gear to start (steps 44 and 46 if necessary), the gear member within the selector gate is moved to the position corresponding to the selector gate 1 / R in step 48 if gear 1 or R is desired If, for example, a winter program specifies that the vehicle should start in second gear, the switching element is moved in step 50 to the shift gate in which the second gear is located. The reverse gear or the first or second gear is then shifted accordingly in steps 50 and 52, respectively, by applying voltage or current of appropriate polarity to the associated electric motor. If it is determined in step 54 by an end stop signal that the corresponding switching element has reached its end stop or end position and the gear is shifted, in step 56 the clutch (not shown) is closed depending on the actuation of the accelerator pedal 26 in particular, so that he starts. If no end stop is detected in step 54 and it is therefore not established that a gear is engaged, the program goes into an emergency operation and / or is informed about the error.

It is understood that the program acc. Fig. 2 can be modified in many ways. For example, before switching steps 50 or 52 additional Lich can be determined whether a brake pedal is actuated, so that it is ensured that the vehicle does not suddenly move unintentionally. This actuation of the brake pedal (shown in dashed lines in FIG. 6) can also be checked in step or before step 42 , wherein the driver may be signaled that an actuation of the brake pedal is necessary in order to trigger the further processes.

Another problem that arises when the vehicle is stopped with the engine running is that, despite the clutch being disengaged, the input shaft of the transmission is not completely stationary. As a result, uncomfortable scratching noises occur when a gear is engaged. To avoid this, corresponding synchronizations of the starting gears can be provided, which is expensive. An advantageous remedial measure for this problem is explained with reference to FIGS. 3 to 5:
In FIG. 3, 60 denotes an end region or transition region in which the selector gate WG merges into the shift gate SG, in which the first gear and the reverse gear lie. A Bremsein is reference to FIG. 5 below-described direction, which is activated when the switching member is moved into the Endbe rich 60th Fig. 4 shows a modified version of a shift scheme, in which the first and second gears are opposite each other in the left shift gate and the end region 60 is formed where the selector gate WG merges into this shift gate SG.

In Fig. 5, the switching member 8 ( Fig. 6) is shown in side view, wherein the shift finger 12 formed on the shift shaft 10 engages in the shift fork 2 , which according to. Fig. 3 the gears 1 / R or gem. Fig. 4, the transitions half turns. On the Ge housing 62 of the transmission, a brake lever 64 is mounted, which is pressed by a spring 66 under elastic bias in contact with the shift fork 2 . The transmission input shaft is designated 68 . 70 denotes a shift fork, not shown in FIG. 6, with the shift fork 2 via the associated shift rod, via which the shift of the respective gearwheels takes place inside the transmission.

The function of the arrangement described is as follows:
If the switching element 8 is moved to the end of the selector slot (acc. Fig. 5 is pressed down), it reaches the end region 60 (Fig. 3 or 4), and brings the lever 64 into engagement with the transmission input shaft 68, so that it is braked. With or after engaging the respective gear, the finger 12 reaches a position which corresponds to that shown in FIG. 5, as a result of which the brake lever 64 is released from the shaft 68 under the action of the spring 66 , so that it moves away when starting or Closing the clutch can rotate normally.

It is understood that corresponding cam surfaces or shaped surfaces can be provided for a targeted actuation of the brake lever 60 . The wide ren understands that the actuation of the brake lever 64 does not have to be carried out directly mechanically by means of the switching element, but that a sensor for sensing the position of the finger 12 can be provided, which actuates a braking device for stopping the input shaft 68 accordingly.

The short distance shown in Fig. 3 between the position in which the brake is actuated se, and the position in which the first gear is engaged is advantageous because the period of time to apply the brake until it engages the first gear can be kept very short. The area in which the input shaft brake is actuated can extend beyond the limit of the neutral alley or into the selection alley into the shaft alleys.

It is understood that the gear teeth of the starting gears are sharpened must have, so that there is no risk that the gear in question despite The transmission input shaft cannot be brought to a standstill.

The invention can be used for all types of automated manual transmissions, these gearboxes can work with or without an interruption in tractive power nen. The invention can also be retrofitted to existing manual transmissions become.

In FIG. 8, the axis of the input shaft is shown in dashed lines 106; Fig. 8 thus represents the upper half of an overall rotationally symmetrical arrangement. The input shaft 106 is mounted in a bearing 122 in the gear housing 124 . An annular braking surface 126 is formed on the gear housing 124 . The brake may be connected to the input shaft 106 or may be rotationally coupled to it, such as via a gear stage or other connection.

The input shaft 106 has an annular recess or a collar which is formed with an external toothing 128 in which lever-shaped centrifugal force elements 130 arranged around the circumference of the input shaft 106 engage. The centrifugal force elements 130 are spanned by a spring ring 132 and are designed such that they form an overall inner ring surface 134 , and are biased under the action of the spring ring 132 in elastic contact with the braking surface 126 . Further, the centrifugal force elements are spans 130 by a stopper ring 136, wherein in the dargestell th in Fig. 8 position of the centrifugal force elements 130, a play between the stop ring 136 and the centrifugal force elements 130 is present.

The function of the described components is as follows:
Fig. 8 shows the position of the centrifugal elements 130 at a standstill, a gear shaft 106. When the input shaft 106 rotates with increasing speed, the centrifugal force elements 130 pivot due to their inert mass as a result of the centrifugal force around their engagement points with the external toothing 128 , which with respect to the rotation of the input shaft 106 has a rotationally fixed connection between the centrifugal force elements 130 and the input shaft 106 be acts outward against the biasing force of the spring ring 132 , so that the contact surfaces of the centrifugal force elements 130 or the annular surface 134 is released from the stationary braking surface 126 and the input shaft can freely rotate. As the speed of the input shaft 106 increases further, the centrifugal force acting on the centrifugal force elements 130 is absorbed by the stop ring 136 , which comes into contact with the bottom of grooves formed in the centrifugal force elements 130 . It is understood that the rings 132 and 166 rotate with the input shaft 106 .

Fig. 10 shows the moment of forces or conditions. In the upper diagram, whose abscissa represents the speed n of the input shaft 106 and whose ordinate represents a force F, the curve I indicates the centrifugal force F _{centrifugally} , into which the centrifugal force elements 130 act as a function of n. Curve II indicates the force F _spring , which sets the spring ring 132 against deformation. F ₀ is in the biasing force with which the spring ring 132 presses the centrifugal elements 130 into contact with the braking surface 126 when the input shaft 106 is at rest. The vertical dashed line indicates the idling speed n _{idling of} the internal combustion engine.

As can be seen, the centrifugal force acting on the centrifugal force elements 130 overcomes the spring force above the idling speed, so that the centrifugal forces are released from the braking surface 126 at speeds above the idling speed. The lower curve III of FIG. 9 indicates the braking torque M _brake , which acts on the input shaft 106 as a function of the speed n. M ₀ is the braking torque acting when the input shaft 106 is stationary, which decreases with increasing speed of the input shaft and finally becomes zero above the idling speed.

It is understood that the braking torque M _{0 is} such that it is easily overcome by the starting torque acting from the internal combustion engine when the clutch engages when starting.

FIG. 9 shows an embodiment modified from FIG. 8.

According to FIG. 9 is a plate spring ring 138 through the teeth 128 in drehfe stem engagement with the input shaft 106. The plate spring ring 138 is bent radially on the inside in such a way that it forms an annular groove 140 in which mass bodies 142 , for example balls, are arranged. With the radially outer periphery of the cup spring washer 138 , a sheet metal ring 144 is rigidly connected, which is shaped such that it forms an opposing ring surface 126 of the braking surface 146 and ends with a conical surface 148 toward the annular groove 140 . An approximately radially directed end face 150 of the input shaft 106 forms a stop face for the spring ring 132 .

The function of the arrangement of FIG. 9 corresponds to that of FIG. 8. For a stationary input shaft 106, the annular surface 146 is pushed due to the elasticity of the plate spring ring 138 into engagement with the braking surface 126. With increasing speed of the input shaft 106 , the mass bodies 142 move radially outwards as a result of the centrifugal force and thereby take the sheet metal ring 144 with them, whereby the disk spring ring 138 deforms against its elasticity and the annular surface 146 is released from the braking surface 126 . As the speed continues to increase, the lower area of the disk spring ring 138 comes into contact with the end face of the input shaft 106 , which in this way forms a stop for the disk spring ring 138 .

It goes without saying that the annular surface 146 or preferably the braking surface 126 can be provided with a brake lining.

The embodiments according to FIGS. 8 and 9, which can be modified in various ways with regard to structural details, work purely mechanically due to centrifugal forces. It is understood that the Bremseinrich device can also be designed such that the speed of the input shaft 106 is electronically detected by a sensor and depending on the speed of the input shaft 106, a brake for the input shaft can be controlled by means of an actuator. In a development such a direction can be designed such that the speed of the output shaft of the transmission is detected and the brake for the input shaft is actuated accordingly.

The clutch 104 ( FIG. 11) need not be a mechanical friction clutch, but can be designed as a hydraulic converter or in some other way. The braking surface 126 does not necessarily have to be formed on a stationary component, for example on the gear housing, but can be connected to a component which in any case rotates slower than the input shaft, for example the output shaft.

With the invention, synchronizations of the starting gears are assigned Gears unnecessary, so that the gearbox is compact and inexpensive and with simple switch elements can be formed.

Another advantage that is achieved with the invention is that a gear and open clutch when the vehicle is at a standstill matic roller lock is created, which prevents the vehicle from the standstill unintentionally move forward or backward in motion gung sets.

Fig. 11 shows a schematic of an automated manual transmission.

An internal combustion engine 102 is connected via a clutch 104 to the input shaft 106 of a manual transmission, generally designated 108 , the output shaft 110 of which leads to the driven wheels of a motor vehicle. On the input shaft 106 and output shaft 110 gear sets are arranged, which can be brought into or out of engagement by means of shift forks for switching the individual gears. In the illustrated example, three switching fork are provided, with each of which gears 1 / R 2/3, 4/5 is switched who can. In addition, an overdrive gear 6 can be shifted. The shift forks are movable with the help of an actuator 112 , for example a shift shaft, which is movable in a selection gate, from the shift gate. A movement actuator 114 is provided for moving the confirmation member along the selection gas; for movement in the direction of the switching lanes, a switching actuator 116 is provided. The clutch 104 can be actuated by means of a clutch actuator 118 . To control the actuators, an electronic control unit 120 is used , which controls the actuators as a function of its inputs supplied signals relevant to the circuit. Functionality and structure of the device are known per se, so that a further description is omitted.

If a vehicle equipped with such an automated manual transmission brakes, for example, clutch 104 is opened at the latest when the internal combustion engine is running at idling speed. If the transmission is additionally shifted into zero gear, the input shaft 106 is neither coupled to the crankshaft of the internal combustion engine nor to the output shaft 110 of the transmission and can rotate freely. Due to the inertia of the clutch disc, the input shaft 106 may require several seconds until it finally comes to a standstill due to bearing friction. In some cases, the clutch 104 does not open completely, so that a remaining torque ver keeps the input shaft 106 at the speed of the cure belwelle.

So that the first gear or the reverse gear or another starting gear The input shaft must be inserted when the vehicle is stationary stand still so that there are no uncomfortable scratching noises or loading  damage to the gears. For this it is known on the gears of the first gear and reverse gear lock synchronizers conditions, the speeds of the input shaft and Synchronize output shaft. Such synchronizations require construction space and incur costs.

The claims submitted with the application are drafted strikes without prejudice for obtaining further patent protection. The An notifier reserves the right to add more, so far only in the description and / or To claim drawings disclosed combination of features.

Relationships used in subclaims point to further training the subject of the main claim by the features of the respective towards subclaim; they are not considered a waiver of achieving one independent, objective protection for the combinations of features of to understand related subclaims.

Since the subjects of the subclaims with regard to the prior art reserves the right to make its own independent inventions on the priority date Applicant before becoming the subject of independent claims or part to make statements of compliance. You can also continue to invent independently containing one of the subjects of the preceding subclaims have independent design.  

The exemplary embodiments are not to be understood as a limitation of the invention hen. Rather, there are numerous variations within the scope of the present disclosure Rations and modifications possible, especially such variants, elements and combinations and / or materials, for example by combination or modification of individual in connection with that in the general Be writing and embodiments and the claims described and in the features or elements contained in the drawings or procedural step ten can be removed by the person skilled in the art with a view to solving the problem and through combinable features to a new item or new ones Lead process steps or process step sequences, also insofar as they Test and work procedures concern.

Claims (29)

1. Device for switching an automated gear shift transmission, ent containing at least one switch element that can be actuated in two dimensions, a first actuator and / or a second actuator for actuating the switch element in the first and / or the second dimension, the switch element being in one of its Movements along a selector lane of a switching device moves, from which selector lane shift lanes emanate, along which the switching element moves during its other movement to shift gears, characterized in that the switching device contains a selector lane crossing the selector lane in such a way that when the movement is moved Switching element in one direction in the shift gate of the first gear and when moving in the opposite direction, the reverse gear is switched. 2. Device for switching an automated gearbox, ent holding a ver pivotable about an axis and along the axis Slidable switching element, a pivot actuator for pivoting the Shaft member and a shift actuator for shifting the shift  member, the switching element moving along one of its movements Selector gate of a switching device moves, from which selector gate switching lanes go out along which the switching element moves in its other movement movement moved to shift gears, characterized in that the Switching device ent a switching lane crossing the selector lane holds that when the switching element moves in one direction in the Schaltgasse the first gear and when moving in the opposite direction Reverse gear is switched. 3. Apparatus according to claim 1 or 2, characterized in that the Shift gate of the first gear and the shift gate of the reverse gear are arranged at the same position in the dialing lane. 4. The device in particular according to claim 1, 2 or 3, characterized records that for moving the switching element along the switching lanes Electric motor is provided, which in a movement from the select lane one direction or the other direction with reversed polarity can be opened. 5. The device in particular according to claim 1, 2 or 3, characterized records that for moving the switching element along the switching lanes Drive like a hydraulic, pneumatic or electromotive drive drove, is provided.   6. Device according to one of claims 1 to 5, characterized in that in addition to the shift gate for switching the first gear a shift alley is arranged to shift the second gear. 7. Device for switching an automated gearbox, ent holding at least one switching element which can be actuated in two dimensions, one first actuator and / or a second actuator for actuating the switch link in the first and / or the second dimension, whereby the Switching element during one of its movements along a dialing lane Switching device moves, from which switching lane switching lanes start, along which the switching element moves in its other movement in order to Shift gears, characterized in that a braking device to brake an input shaft of the transmission, the switching device of the is trained that when shifting from zero gear, such as neutral po sition, is activated in a start gear. 8. Device for switching an automated gearbox, ent holding a ver pivotable about an axis and along the axis Slidable switching element, a pivot actuator for pivoting the Switching element and a shift actuator for shifting the shift member, the switching element moving along one of its movements Selector gate of a switching device moves, from which selector gate switching  lanes go out along which the switching element moves in its other movement movement moved to shift gears, characterized in that a Braking device for braking an input shaft of the transmission Switching device is designed such that when switching from the Zero gear in a starting gear is activated. 9. The device according to claim 7 or 8, characterized in that the Activation by means of one actuator and / or the other actuator follows. 10. The device according to claim 7 or 8, characterized in that the Activation is carried out by means of the switching actuator and / or the selection actuator. 11. The device according to claim 7 or 8, characterized in that he highest gear and reverse gear in a common shift gate are arranged, which starts from an end region of the dialing lane, and that the Braking device is designed such that when the Switching element is activated at the edge area. 12. The apparatus according to claim 11, characterized in that a ver pivotable brake lever is provided by the switching element in Anla  ge to the input shaft or an associated part of the transmission bes is movable. 13. The apparatus according to claim 12, characterized in that the Bremshe bel elastic against a movement of the switching element along one outer shift gate actuated shift fork is pushed and at a loading movement of the switching element in the associated end region of the dialing lane is pushed by the switching element into contact with the input shaft. 14. The device according to one of claims 1 to 13, characterized in that that when the vehicle is at a standstill, a shift into one gear only brake pedal. 15. Device for braking the input shaft of a manual transmission, ent holding a brake responsive to the speed of the input shaft direction, which falls below a predetermined speed Exerts braking torque on the rotating input shaft and thereby a Decelerates the rotating input shaft. 16. The apparatus of claim 15, wherein the on the speed of the input shaft-responsive braking device rotatably with the input shaft connected module which, when the input shaft is at a standstill  Brake intervention and with increasing speed of the input shaft releasing the brake engagement while overcoming a preload. 17. The apparatus according to claim 16, characterized in that the assembly pe has at least one element that is radial under the influence of centrifugal force strives outwards. 18. The apparatus according to claim 17, characterized in that the element acts against the restoring force of a resilient element. 19. The apparatus according to claim 18, characterized in that the elastic Element is biased. 20. The apparatus according to claim 17 or 18, characterized in that the Element is a spring, such as an annular spring. 21. Device according to one of the preceding claims, wherein the construction Group is attached to the input shaft in such a way that its position is relative to the input shaft with increasing speed due to centrifugal force different.   22. The apparatus of claim 21, wherein the assembly several along the Circumference of the input shaft on this pivotally attached centrifugal force has telemente, the total of an inner ring surface for an engagement form with a fixed braking surface. 23. The apparatus of claim 22, wherein the centrifugal elements of a Fe derring are elastically biased towards the braking surface. 24. Device according to one of the preceding claims, characterized records that a fixed stop is provided for the centrifugal force elements. 25. The apparatus of claim 22, 23 or 24, wherein the centrifugal elements are surrounded by a stop ring. 26. The device according to any preceding claim, wherein the assembly has a disc spring ring connected to the drive shaft in a rotationally fixed manner, which deforms with increasing speed of the input shaft, so that ei ne ring surface connected to it out of engagement with a stationary brake area comes. 27. The apparatus of claim 26, wherein the spring washer radially inside under Formation of a ring groove open to the outside is bent in the bulk  are arranged by moving one with the disc spring ring connected form rings with increasing speed of the input times move radially outwards. 28. The apparatus of claim 27, wherein the shaped ring with an annular surface System is formed on the braking surface. 29. Device according to one of the preceding claims, wherein the one gear shaft via a coupling device with an internal combustion engine is connected and the braking device is designed such that it Brakes input shaft at a speed that is about the idle speed corresponds to the internal combustion engine.