JPS63113131A - Car slip control device - Google Patents

Abstract

PURPOSE:To prevent deceleration shock due to slip control by setting an opening of a throttle valve at a magnitude obtained through subtraction of a specified amount from the maximum opening of the throttle valve for a specified period of time from the time when the rotating acceleration of a combustion engine remains below a specified value and the rotating acceleration of a driving wheel becomes above a specified value. CONSTITUTION:An opening correcting means M12 judges that the upshift is completely carried out by an automatic change gear M3 when the rotating acceleration of a combustion engine M1 calculated by an engine acceleration calculating means 10 remains below a specified value and the rotating acceleration of a driving wheel M2 calculated by a driving wheel calculating means M11 becomes above a specified value. For a specified period of time, an opening of a throttle valve M6 driven by a control means M7 is set at a magnitude obtained by subtracting a specified amount from the maximum opening of the throttle valve M6 memorized by an opening memory means M9. Thus, the deceleration shock can be prevented by setting the opening of the throttle valve M6 at a magnitude obtained by subtracting a specified value from the maximum opening directly before abrupt reduction caused by a peak of driving wheel speed.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a vehicle slip control system that controls the rotation of the drive wheels so that the frictional force between the tires of the drive wheels and the road surface increases when the vehicle accelerates. The present invention relates to a control device, and specifically relates to a vehicle slip control device that controls the rotation of drive wheels by controlling the throttle valve opening and controlling the output of an internal combustion engine.

[Prior art] When a vehicle starts or accelerates while driving, acceleration slip may occur in the drive wheels, but in this case, the drive wheels simply spin, shortening the life of the tires. In addition, the lateral drag between the tires and the road surface also decreases, causing various problems such as loss of maneuverability and worsening fuel efficiency.

In recent years, as a countermeasure to this problem, when acceleration slip occurs, the throttle valve installed in the intake system of the internal combustion engine is driven in the closing direction to reduce the amount of intake air, suppress the output torque of the internal combustion engine, and Vehicle slip control devices have been proposed that are configured to reduce rotation. For example, the vehicle slip control device previously proposed by the present applicant in Japanese Patent Application No. 61-31642 is of this type, in which the rotational speed of the drive wheels and
The slip state of the driving wheels is detected from the deviation between the target speed calculated from the rotational speed of the idle wheels, and the output torque of the internal combustion engine is controlled by opening and closing the throttle valve of the internal combustion engine according to the slip state. Controls acceleration slip.

[Problems to be Solved by the Invention] However, when the vehicle slip control device of the above-mentioned conventional technology is to be installed in a vehicle equipped with an automatic transmission, the vehicle slip control device has the following problems. However, it was still not sufficient.

In other words, in a vehicle equipped with an automatic transmission, when the automatic transmission performs an upshift, the engine rotational speed suddenly decreases, and the rotational speed of the drive wheels suddenly peaks due to sudden changes in the output torque. Occurs (see Figure 6)
. Then, the vehicle slip control device calculates the throttle opening degree in accordance with the sharp peak of the rotational speed, and the throttle valve is rapidly driven in the closing direction. For this reason, there was a problem in that a large engine brake was suddenly applied and a deceleration shock occurred.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle slip control device that can prevent deceleration shock caused by vehicle slip control that occurs during upshifting of an automatic transmission. There is.

Structure of the Invention [Means for Solving the Problems] In order to achieve the above object, the following structure was adopted as a means for solving the problems of the present invention. That is, the present invention
As shown in FIG. 1, driving wheel speed detection means M4 is mounted on a vehicle equipped with an automatic transmission M3 that transmits the output of the internal combustion engine M1 to the driving wheels M2, and detects the rotational speed of the driving wheels M2; The slip state of the drive wheel M2 is detected using the detected speed of the drive wheel M2 as one parameter, and the throttle valve M6 provided in the intake passage M5 of the internal combustion engine M1 is adjusted according to the detected slip state of the drive wheel M2. drive,
A vehicle slip control device comprising: a control means M7 for controlling the rotation of the drive wheel M2; and an opening detection means M8 for detecting the opening degree of the throttle valve M6; When the internal combustion engine M1 is displaced in the direction, the opening storage means M9 temporarily stores the previous maximum opening degree, and detects the rotational speed of the internal combustion engine M1, and calculates the rotational acceleration of the internal combustion engine M1 from the rotational speed. an engine acceleration calculation means M10 for calculating the rotational acceleration of the driving wheel M2 from the rotational speed of the driving wheel M2 detected by the driving wheel speed detection means M4; Means M
For a predetermined period of time from when the rotational acceleration of the internal combustion engine M1 calculated by the IO is less than or equal to a predetermined value and the rotational acceleration of the drive wheel M2 calculated by the drive wheel acceleration calculation means M11 is greater than or equal to a predetermined value, the control means an opening correction means M12 that determines the opening degree of the throttle valve M6 driven by M7 to a size obtained by subtracting a predetermined amount from the maximum opening degree of the throttle valve M6 binarized by the opening storage means M9; The gist of the present invention is a vehicle slip control device that is characterized in that it is provided with a vehicle slip control device.

[Function] In the vehicle slip control device of the present invention configured as described above, the opening storage means M9 reads the opening of the throttle valve M6 detected by the opening detection means M8, and stores the opening of the throttle valve M6. It temporarily stores the maximum opening degree immediately before when the opening is displaced in the closing direction.

On the other hand, the engine acceleration calculation means M10 reads the rotational speed of the internal combustion engine M1, and calculates the rotational acceleration of the internal combustion engine M1 from the rotational speed. Further, the driving wheel acceleration calculation means M11 reads the rotational speed of the driving wheel M2 detected by the driving wheel speed detection means M4, and calculates the rotational speed of the driving wheel M2 from the rotational speed.
The rotational acceleration of 2 is calculated.

The opening correction means M12 reads each control signal from the opening storage means M9, the engine acceleration calculation means M10, and the drive wheel acceleration calculation means M11, and the control means M7 adjusts the driving wheel M.
Throttle valve M that is driven according to the slip state of 2.
6 is set to a predetermined value. That is, the opening correction means M
12, when the rotational acceleration of the internal combustion engine M1 calculated by the engine acceleration calculation means M10 is less than a predetermined value, and the rotational acceleration of the drive wheel M2 calculated by the drive wheel acceleration calculation means M11 is more than a predetermined value. , it is determined that an upshift has been executed by the automatic speed change IM3, and the opening degree of the throttle valve M6 to be driven by the control means M7 is stored in the opening degree storage means M.
The predetermined period window is set to a value obtained by subtracting a predetermined value from the maximum opening degree of the throttle valve M6 stored in step 9. Therefore, even if an upshift is executed in the automatic transmission lIM3 and a sharp peak occurs in the rotational speed of the driving wheel M2, the opening degree of the throttle valve M6 is changed immediately before the sudden decrease due to the peak in the driving wheel speed. The size can be determined by subtracting a predetermined amount from the maximum opening.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a schematic configuration diagram of an embodiment of the present invention, in which the present invention is applied to a front engine rear drive (FR system) automobile equipped with a gasoline engine.

In the figure, 1 is an engine with a four-cylinder fuel injection type engine, 2 is an intake pipe, 3 is a surge tank, 4 is an air flow meter, 5 is an air cleaner, and 6 is provided for each cylinder that supplies fuel into the intake air. 7 is the spark plug (
In the figure, only the fuel injection valve 6 and spark plug 7 for one cylinder are shown. ), 8 is a distributor that supplies high voltage to the spark plug, 9 is an engine speed sensor consisting of a gear and an electromagnetic pickup, and 10 is driven via a link mechanism in response to depression of the accelerator pedal 11 to adjust the intake air amount. A first throttle valve 12 is a second throttle valve that is provided upstream of the first throttle valve 10 and adjusts the amount of intake air during vehicle slip control; 13 is a second throttle valve 12;
A DC motor drives the throttle valve 12, and 14 represents a second throttle sensor that detects the throttle opening of the second throttle valve 12.

The second throttle sensor 14 outputs a detection signal corresponding to the opening degree of the second throttle valve 12, and when the opening degree is small, a low voltage is output.

When the opening degree is large, a high voltage is output.

On the other hand, 20.21 represents the left and right drive wheels, respectively, and the power of the engine 1 is transmitted to the output shaft 22. It is transmitted via the automatic transmission 23, propeller shaft 24, etc. Also, 25.26 are left and right drive wheels 20 and 21, respectively.
27. left and right drive wheel speed sensors for detecting rotational speeds of the wheels;
Reference numeral 28 denotes left and right driven wheels which are rotated as the vehicle travels, and 29 and 30 denote left and right driven wheel speed sensors, respectively. The automatic transmission 23 is equipped with a shift position sensor 31 that detects the shift position of the automatic transmission 23, and transmits a control signal from the automatic transmission control device 32 to the shift solenoid valves 33, 34 and the lock-up solenoid. It is received by the valve 35 and performs speed change control. Note that these speed change mechanisms and the control of the automatic speed change control device 32 are well known, so their explanations will be omitted.

Further, 40 indicates a drive control device, and here the rotational speed sensor 9. Second throttle sensor 14° automatic shift control device 32. Left driving wheel speed sensor 25° Right driving wheel speed sensor 26. Upon receiving various output signals from the left driven wheel speed sensor 29 and the right driven wheel speed sensor 30, the following processing is executed, and the second Engine output control, ie, slip control, is performed in which a drive signal is output to the DC motor 13 to adjust the opening degree of the throttle valve 12.

In this embodiment, it is assumed that the drive control circuit 40 is constructed using a microcomputer.To proceed with the explanation, the structure of the drive control circuit 40 can be expressed as shown in FIG. In the figure, reference numeral 41 denotes a central processing unit (CPU) that inputs and calculates data detected by the above-mentioned sensors according to a control program, and performs processing for driving and controlling the DC motor 13;
43 is a read-only memory (ROM) in which data such as the control program and map is stored; 43 is a random access memory (RAM) in which data from each sensor and data necessary for arithmetic control are temporarily stored; 44 45 is an input section equipped with a waveform shaping circuit and a multiplexer that selectively outputs the output signals of each sensor to the CPU 4.1; 45 is an output section equipped with a drive circuit that drives the DC motor 13 according to a control signal from the CPU 41; 46 is CPU41, R
A path line 47 connects each element such as the OM 42, the input section 44, and the output section 45 and serves as a path for various data, and 47 represents a power supply circuit that supplies power to each of the above sections.

Next, the slip control executed by the drive control circuit 40 configured as described above will be explained based on the flowchart of the control program shown in FIG. This routine starts when the vehicle's starter switch is turned on.
1 is executed repeatedly.

First, when the processing of this routine is started, initialization processing such as clearing the contents of the RAM 2S and resetting each flag and counter is executed (step 100) to prepare for the following processing. Next, rotation speed sensor 9. Throttle sensor 1
4 and speed sensors 25, 26, 2 provided on each wheel.
The detection signals from 9 and 30 are read and the rotational speed of engine 1 is determined as NE.

Throttle opening θ1 of the second throttle valve 12, left/
The average rotational speed VR of the right driving wheel (hereinafter referred to as driving wheel speed) and the average rotational speed VF of the left and right driven wheels (hereinafter referred to as driven wheel speed) are calculated (step 110). Next, based on the submerged driven wheel speed VF, a target wheel speed VT for determining acceleration slip is calculated using the following formula (%) (step 120). Note that this coefficient is 1.
2 was set to control the rotation of the drive wheels so that maximum frictional force is generated between the drive wheel tires and the road surface during acceleration, and optimal acceleration performance is obtained, that is, the slip ratio is 20%. It is a value.

Subsequently, when an upshift signal indicating an upshift is sent from the automatic transmission control device 32, that signal is read, and when an upshift occurs and an upshift signal is sent, the value 1 is stored in the flag F1. (Step 130). Next, it is determined whether the driving wheel speed VR calculated in step 110 exceeds the target wheel speed VT, that is, whether the slip rate of the driving wheels exceeds 20% and the tires have begun to spin (step 140). When it is determined that the driving wheel speed VR exceeds the target wheel speed VT, the target opening degree θ(n) of the second throttle valve 12 is determined.
is calculated using the following formula (1) using the drive wheel speed VR and target wheel speed VT calculated above (step 150).
.

θ(n)=θ(n-1>-KC-(VR-VT)...
(1) However, KC is the closing side correction coefficient of the second throttle valve 12, and θ(n-1> is the previously calculated target opening degree of the second throttle valve 12).

On the other hand, when the driving wheel speed VR is determined to be equal to or lower than the target wheel speed VT, the target opening degree θ(
n), the driving wheel speed VR calculated above and the target wheel speed V
Calculate using the following formula (2) using T (step 16
0).

θ(n)=θ(n-1)+KO-(VT-VR)...
(2) However, KO is the opening side correction coefficient of the second throttle valve 12, and θ(n-1> is the previously calculated target opening degree of the second throttle valve 12).

After executing the process of step 150 or step 160,
Next, an upshift determination process is executed to determine whether or not an upshift has actually been performed in the automatic transmission 23 based on the rotational speed of the engine 1, the degree NE, and the drive wheel speed VR calculated in step 110 ( step 170). A detailed explanation of this upshift determination process will be given later, but in this process, when it is determined that an upshift has been executed, the flag F2 is set to a value of 1, and the throttle opening θ calculated in step 110 is When the valve is displaced in the direction, a process is performed in which the immediately previous maximum opening degree is stored in the variable θMAX.

Next, it is determined whether the flag F2 set in the upshift determination process is 1 (step 180).
), if the flag F2 is determined to be 1, the target opening θ(
n) (step 190). On the other hand, flag F2
If it is determined that the value is not 1, the process of step 190 is skipped. Next, the DC motor 13 is driven to determine the actual opening e of the second throttle valve 12 based on the target opening θ(n) of the second throttle valve 12 calculated above (step 200), and the process then proceeds to step 110. The process moves to Step 110 to Step 200 and repeats the processing.

Next, the upshift determination process executed in step 170 will be explained based on the flowchart of the control program shown in FIG.

When the process is started, it is determined whether the flag F2 is O or not (step 300), and if it is determined that F2=O, the following process is executed. First, it is determined in step 310 whether the flag F1 set in step 130 is 1 or not.
), a counter C indicating the elapsed time from the time when the flag F1 becomes the value 1, that is, the time when the upshift signal is received from the automatic transmission control device 32.
Increment NT1 by the value 1 (step 320
). Next, it is determined whether the counter CNT1 is less than a predetermined time T1, in this embodiment 0.1 to 2.0 SeC1 (step 330), and if it is determined that CNT1≦T1, the time calculated in step 110 of FIG. A determination is made as to whether the rotational speed NE of the engine 1 is greater than the previously stored rotational speed NEMAX (step 340).

If it is determined in step 340 that NE>NEMAX,
Assuming that the rotational speed NE is still in the process of increasing, the current rotational speed NE is set in the j' memory area NEMAX, and the current second value is read in the maximum throttle opening memory area θMAX in step 110 of FIG. The throttle of the throttle valve 12: the opening degree θ is set (Step 35o), and the processing of this routine proceeds to Step 180 in FIG.

If it is determined in step 340 that the rotational speed NE is less than or equal to the previously stored rotational speed NEMAX, then the rotational speed N
Step 3: Increment the counter CNT2, which indicates the elapsed time since E became less than NEMAX, by the value 1.
60), it is determined whether the counter CNT2 is less than or equal to a predetermined time T2 (for example, 0.1 to 0.5 sec) (step 370). If the counter CNT2 is determined to be equal to or lower than T2, the deviation ΔNE between the current rotational speed NE and the rotational speed NEMAX of the engine 1 is calculated, and the deviation ΔN
E is the predetermined rotational speed KNE (for example -200 to -4
0Orpm) or less is determined in step 38.
0), then the current driving wheel speed VR and step 12
A determination is made as to whether the deviation ΔVR from the target wheel speed VT calculated at 0 is equal to or higher than a predetermined speed KVR1 (for example, 2 to 5 km/h) (step 390). In step 380, it is determined that ΔNE≦KNE, and in step 390, ΔV
If it is determined that R≧KVR1, an upshift is actually executed in the automatic transmission 23, and the value 1 is set in the flag F2 (step 400).
, handles the processing of this routine.

On the other hand, if it is determined in step 370 that more than the predetermined time period "2" has elapsed since the rotational speed NE began to decrease, an upshift signal is received from the automatic transmission control device 32, but no upshift is actually performed. In step 410, the flag F1 is cleared to the value O.
), centralizes the processing of this routine. Furthermore, if the torque change during upshifting is small before upshifting or even though upshifting is actually performed in automatic transmission 23, step 38
A negative determination is made at 0.390, and the processing of this routine is terminated. If it is determined in step 330 that a predetermined period of time or more has elapsed since receiving the upshift signal, step 410 is executed in the same way as if no upshift was performed, and the process of this routine is terminated. Let's go.

Furthermore, if it is determined in step 310 that the flag F1 is not the value 1, that is, it is determined that no upshift signal has been received,
The processing of steps 320 to 410 can be skipped and the processing of this routine can be handled.

On the other hand, if it is determined in step 300 that the flag F2 is not the value O, the following processing is executed. First, a counter CNT indicating the elapsed time from the time when the flag F2 became the value 1.
3 by the value 1 (step 510), and then the counter CNT3 is incremented by the value 1 for a predetermined time T3 (for example, 0.2
In step 520), if it is determined that the time is greater than the predetermined time T3, each counter CNTl, CNT2 . Clear CN-3 and each flag Fl, F2 to the value O (Step 5
30). On the other hand, in step 520, CNT3
3 or less, the deviation ΔVR of the drive wheel speed VR calculated in the same manner as in step 390 becomes the predetermined speed KVR2 (
If it is determined that ΔVR≦KVR2, step 530 is executed. Furthermore, step 5
20, it is determined that CNT3≦T3, and step 53
0 and it is determined that ΔVR>KVR2, step 53
Skip processing of 0. After that, you can handle the processing of this routine.

Next, the slip control executed in the slip control routine will be explained based on the timing chart of FIG. 6. When an upshift is executed in the automatic transmission 23, the automatic transmission control device 32
When an upshift signal is received, the flag F1 becomes 1, and thereafter the rotational speed NE begins to decrease. On the other hand, at this time, the driving wheel speed VR begins to increase rapidly. As shown in the figure, a time t after a predetermined time Δt has elapsed from time t1.
2, 1, deviation ΔNE of rotational speed NE of engine 1
is below KNE (-200 to -40 Orpm), and the deviation ΔVR of driving wheel speed VR is KVRl (2 to 5 km/
h) If it is above, an upshift is executed in the automatic transmission 23 and the torque change during the upshift is large, and the flag F2 is set to 1.
Make it.

On the other hand, as the drive wheel speed R suddenly increases, the second throttle opening θ gradually begins to decrease (displaces in the closing direction). is determined at time t2 by subtracting θ from the local maximum value θMAX immediately before the decrease of the second throttle opening θ by a predetermined value. Thereafter, the second throttle opening degree θ is fixed at this range until time t3 when the deviation ΔVR between the drive wheel speeds V and R satisfies the condition ΔVR≦KVR2.

Therefore, according to the slip control of this embodiment, sudden engine braking can be prevented without closing the second throttle valve 10 too much during an upshift. Therefore, as shown in the lower part of Fig. 6, the acceleration G in the longitudinal direction of the vehicle, which previously showed a sudden drop as shown by the broken line in the figure, has been reduced to an almost constant value in the longitudinal direction of the vehicle. acceleration G can be maintained. Therefore, unpleasant deceleration shock for the occupants is prevented.

In the above embodiment, only when an upshift signal is received from the automatic transmission control device 32 and the flag F1 becomes 1, the deviation between NE and the deviation ΔVR between the engine rotational speed and the driving wheel speed VR is calculated. Erroneous detection during upshifting is prevented by executing condition judgment, but instead of the above embodiment, the automatic transmission can be detected only by the deviation ΔNE of the engine rotation speed and the deviation ΔVR of the driving wheel speed VR. It may be configured such that the upshift signal from the automatic transmission control device 32 is not received by determining the upshift time of the automatic transmission control device 32, and the effects of the present invention can be sufficiently achieved even with such a configuration.

Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the above embodiments in any way, and it goes without saying that various embodiments may be made without departing from the gist of the present invention.

For example, in the vehicle slip control device that has been described in detail above, even when an upshift is executed in the automatic transmission, the opening degree of the throttle valve does not drop suddenly. Therefore, sudden engine braking does not occur, and unpleasant deceleration shock for the occupants can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a basic configuration diagram of the present invention, FIG. 2 is a schematic configuration diagram of an embodiment of the present invention, and FIG. 3 is a block diagram of its control system.
4 and 5 are flowcharts of a slip control routine executed by the control system, and FIG. 6 is a timing chart illustrating the control. 1... Engine 6... Fuel injection valve 9... Rotational speed sensor 12... Second throttle valve 20.21... Left and right drive wheels 23... Automatic transmission 32...
・Automatic shift control device 40...drive control device

Claims (1)

[Scope of Claims] Driving wheel speed detection means installed in a vehicle equipped with an automatic transmission that transmits the output of an internal combustion engine to driving wheels, and detecting the rotational speed of the driving wheels; and the detected driving wheel speed. control means for detecting a slip state of the drive wheels using as one parameter, and controlling the rotation of the drive wheels by driving a throttle valve provided in an intake passage of the internal combustion engine according to the detected slip state of the drive wheels; and a vehicle slip control device comprising: an opening detection means for detecting the opening of the throttle valve; and when the detected opening of the throttle valve is displaced in the closing direction, the maximum opening just before an opening storage means for temporarily storing the rotational speed of the internal combustion engine; an engine acceleration calculation means for detecting the rotational speed of the internal combustion engine and calculating the rotational acceleration of the internal combustion engine from the rotational speed; and the driving wheel speed detection means. a driving wheel acceleration calculation means for calculating the rotational acceleration of the driving wheel from the detected rotational speed of the driving wheel; and the rotational acceleration of the internal combustion engine calculated by the engine acceleration calculation means is equal to or less than a predetermined value, and the driving wheel acceleration calculation means For a predetermined period of time from when the rotational acceleration of the driving wheels calculated by the means becomes equal to or higher than a predetermined value, the opening degree of the throttle valve driven by the control means is changed to the maximum opening of the throttle valve stored in the opening storage means. 1. A vehicle slip control device comprising: an opening correction means that sets the opening degree to a value obtained by subtracting a predetermined value from the opening degree.