JPH11351367A - Acceleration slip control device for vehicle with automatic transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of uncomfortable vibration at a relatively low cost by estimating the braking force to be applied to driving wheels on the basis of the output signal of a braking force adjusting means, and commanding gear shift to a gear shift control means so as to reduce the driving torque to be transmitted to the driving wheels. SOLUTION: Driving torque generated in an engine 1 is transmitted to a left and a right front wheels 7FL, 7FR through an automatic transmission (AT) 3, a differential device 5, and driving shafts 6L, 6R. An AT electronic control device 200 and a traction electronic control device 50 are connected to each other so as to transmit the control data between them. A micro computer 52 separately computes the controlled variable so that a target rotating speed and a real rotating speed V1 , V2 of the left and the right driving wheels 7FL, 7ER coincide with each other, and controls the braking force of each driving wheel. Simultaneously, the micro computer 52 estimates the braking force of each driving wheel, and in the case where the estimated braking force is larger than the predetermined value, the micro computer 52 outputs the shift-up gear change command to the AT electronic control device 200 so as to perform the optimal traction control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acceleration slip control device for a vehicle equipped with an automatic transmission for performing traction control of a vehicle equipped with an automatic transmission.

[0002]

2. Description of the Related Art Preventing excessive slip of a drive wheel on a road surface is effective in obtaining a propulsive force of a vehicle effectively and in terms of safety such as preventing spin. Then, in order to prevent the slip of the drive wheel, the net drive torque of the drive wheel that causes the slip may be reduced. As described in the related art of Japanese Patent Publication No. 2502982, for example, a device that performs this type of acceleration slip control includes a device that adjusts only a braking force to adjust a net drive torque, and a device that adjusts a torque generated by an engine. A combination of the adjustment and the adjustment of the braking force is illustrated.

[0003]

If an attempt is made to control the driving wheel slip by only the braking force adjusting means for the net driving torque of the driving wheels, unpleasant vibrations may occur when the torque generated by the engine is large. In order to solve this problem, it is common to use the adjustment of the engine output as described above. However, in such a solution, it is necessary to add a new device such as a mechanism for adjusting a throttle valve in order to continuously adjust the generated torque of the engine, and the acceleration slip control device becomes expensive.

Accordingly, the present invention has been made in view of the above-mentioned problems in the conventional acceleration slip control device, and the present invention provides a relatively inexpensive acceleration slip control device for a vehicle with an automatic transmission. The purpose is to:

[0005]

SUMMARY OF THE INVENTION An acceleration slip device for a vehicle with an automatic transmission according to the present invention is interposed between an engine and driving wheels and is used when a vehicle with an automatic transmission starts shifting automatically by a shift control means. Or an acceleration slip control device configured to detect a slip of the drive wheel with respect to a road surface generated during acceleration and to suppress the slip of the drive wheel by a braking force adjusting unit that adjusts a braking force of the drive wheel based on the detection result. A braking force estimating means for estimating a braking force acting on the driving wheel based on an output signal of the braking force adjusting means, and a gear shift for reducing a driving torque transmitted to the driving wheel based on an estimation result of the braking force estimating means. The control means is provided with a shift instruction means for giving a shift instruction.

Another embodiment of the present invention relates to an acceleration slip control device for a vehicle with an automatic transmission, which is interposed between an engine and a drive wheel and starts the vehicle with an automatic transmission automatically shifted by a shift control means. Vehicle with an automatic transmission, wherein the slip of the drive wheel is suppressed by braking force adjusting means for detecting the slip of the drive wheel with respect to the road surface generated at the time of acceleration or acceleration and adjusting the braking force of the drive wheel based on the detection result. The braking force estimating means for estimating the braking force acting on the driving wheel based on the output signal of the braking force adjusting means, and the drive transmitted to the driving wheel based on the estimation result of the braking force estimating means. In order to reduce the torque, a calculation is performed based on a shift instruction means for giving a shift instruction to the shift control means, a driving torque transmitted from the engine to the driving wheels, and an estimation result of the braking force estimation means. A net driving torque calculating means for calculating a net driving torque as the difference between the estimated braking force,
When the net drive torque value estimated as a result of the adjustment by the braking force adjusting unit after the shift based on the shift instruction does not become smaller than the net drive torque value before the shift, the shift control unit transmits the drive torque to the drive wheels. And a shift instructing means for issuing a shift instruction to reduce the shift.

Further, the shift instructing means issues a shift instruction when the estimated braking force is larger than a predetermined braking force as a function of increasing an accelerator pedal depression amount for adjusting a load state of the engine.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 The first embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a diagram showing an entire configuration of a front wheel drive type vehicle to which an acceleration slip control device according to the present invention is applied. FIG.
The left and right front wheels 7FL and 7FR are driving wheels, and the left and right rear wheels 7RL and 7RR are driven wheels. The driving torque generated by the engine 1 mounted on the front of the vehicle body is controlled by an automatic transmission 3 (hereinafter referred to as AT) including a torque converter 3a, a planetary gear type transmission gear mechanism 3b, and a transmission hydraulic control device 3c.
), The differential device 5 and the left and right front wheel drive shafts 6L, 6
Via R, it is transmitted to the left and right front wheels 7FL, 7FR.

The intake pipe 1b of the engine 1 is provided with a throttle valve 1a connected so as to interlock with the accelerator pedal 9, and such a vehicle detects the opening θ of the throttle valve 1a. Throttle opening sensor 60
And an engine speed sensor 61 for detecting an output speed of the engine 1. The AT3 includes an AT output rotation speed sensor 62 for detecting the rotation speed Vat of the output shaft of the AT3. The shift hydraulic pressure control device 3c has a plurality of shift valves (not shown), and controls each shift speed of the AT3 by changing the drive state of each shift valve.

The AT electronic control unit 200 and the traction electronic control unit 50 are connected so that control data can be transmitted and received between them. When the drive wheels are not slipping, the AT electronic control unit 200 performs control to a gear position determined by the rotation speed Vat corresponding to the vehicle speed and the opening degree θ.
Drive the shift valve. Each wheel 7FL, 7FR, 7RL,
Around 7RR, wheel speed sensors 64FL, 64FR, 64RL and 64RR for detecting the rotational speed of each wheel, and wheel cylinders 38FL and 38F which are hydraulic actuators for adjusting the braking force of each wheel.
R, 38RL, and 38RR are provided.

The traction electronic control unit 50 includes a microcomputer 52 and a drive circuit 54. The microcomputer 52, which is not shown in FIG. 1, includes, for example, a central processing unit (CPU) and a read-only memory (not shown). ROM) and random access memory (R)
AM) and an input / output port device, which may be of a general configuration connected to each other by a bidirectional common bus.

The input / output port device of the microcomputer 52 includes an engine speed VE detected by an engine speed sensor 61 and wheel speed sensors 64FL to 64RR.
Signals VFL to VRR indicating the wheel speeds of the left and right front wheels and the left and right rear wheels, a signal δ indicating the steering angle detected by the steering angle sensor 65, and the pressure in the accumulator 36 detected by the pressure sensor 66. The signal Pa and the brake signal SB of the brake switch 8 which is turned on / off in conjunction with the brake pedal 12 (step on when SB = 1, SB
= 0 (non-stepped-on state).
Further, a signal G_position indicating a shift speed of AT3 and an opening degree θ which is a signal indicating a throttle opening degree are input from the AT electronic control device 200, and a shift instruction flag F
_2nd information is output to the AT electronic control device 200.

The ROM of the microcomputer 52
Stores a control flow and a map to be described later.
U performs various calculations based on the parameters detected by the various sensors described above, as described later. Specifically, the independent target rotation speed Vti of the left and right drive wheels Vi (hereinafter represented by the suffix i, i = 1 and the left drive wheel i = 2 represents the right drive wheel) is independent so that the actual rotation speed Vi matches. The control amount is calculated to control the braking force of each driving wheel, and the braking force of each driving wheel is estimated. If the estimated braking force Yi is larger than a predetermined value, the AT electronic control unit shifts up. Outputs an instruction and performs suitable traction control.

FIG. 2 is a diagram schematically showing a configuration of a vehicle braking device according to Embodiment 1 of the present invention. In FIG. 2, the braking device 10 includes a master cylinder 14 that pumps brake oil from a first port 14a and a second port 14b in response to a driver's depressing operation of a brake pedal 12. The first port 14a is connected to brake fluid pressure control devices 18 and 20 for left and right front wheels by a brake fluid pressure control conduit 16 for front wheels, and the second port 14b is connected to a rear wheel having a proportional valve 22 in the middle. Are connected to brake fluid pressure control devices 26 and 28 for the left and right rear wheels.

Further, the braking device 10 includes an oil pump 34 that pumps up the brake oil stored in the reservoir 30 and supplies it to the high-pressure conduit 32 as high-pressure oil. The high-pressure conduit 32 is connected to each of the brake fluid pressure control devices 18, 2,
0, 26, and 28, and an accumulator 36 is connected in the middle thereof.

Each of the brake fluid pressure control devices 18, 20, 2
6, 28 are wheel cylinders 38FL, 38FR, 38R for controlling braking force on the corresponding wheels.
L, 38RR, 3 port, 2 position switching type electromagnetic control valve 40FL, 40FR, 40RL, 40RR, normally open type electromagnetic type provided between low pressure pipe 42 and high pressure pipe 32 connected to reservoir 30. Open / close valves 44FL, 44F
R, 44RL, 44RR, and a normally closed electromagnetic on-off valve 46FL, 46FR, 46RL, 46RR.

On-off valves 44FL, 44FR, 44RL, 4
4RR and on-off valves 46FL, 46FR, 46RL, 46
The high-pressure conduits 32 connecting to the RRs are connected to the control valves 40FL, 40FR, 40RL, 40RR by connecting conduits 48FL, 48FR, 48RL, 48RR. The wheel cylinders 38FL, 38F
Although R, 38RL, and 38RR are also described in FIG. 2 for convenience of description, the actual mounting position is the position shown in FIG.

The control valves 40FL and 40FR are designed to switch between a first position and a second position.
When in the first position, the brake fluid pressure control conduit 16 for the front wheels and the wheel cylinders 38FL and 38
FR, and disconnects the wheel cylinders 38FL and 38FR from the connection conduits 48FL and 48FR (the positions shown in the drawing). When in the second position, the brake fluid pressure control conduit 16 and the wheel cylinders 38FL and 38FR are connected to each other. And the wheel cylinder 38F
L and 38FR communicate with connecting conduits 48FL and 48FR.

Similarly, control valves 40RL and 40RR
When in the first position, the brake fluid pressure control conduit 24 for the rear wheels communicates with the wheel cylinders 38RL and 38RR and the wheel cylinder 38R
L and 38RR and the connecting conduits 48RL and 48RR, but when in the second position, the brake hydraulic control conduit 24 and the wheel cylinders 38RL and 38RR.
R, and the wheel cylinders 38RL and 38RR communicate with the connection conduits 48RL and 48RR.

Accordingly, the control valves 40FL, 40FR, 40
When the RL and 40RR are in the first position, the pressure generated in the brake oil in the master cylinder 14 by depressing the brake pedal 12 is transmitted to the wheel cylinders 38FL, 38FR, 38RL and 38RR,
A braking force according to the depression force of the brake pedal can be obtained.

The control valves 40FL, 40FR, 40R
When L and 40RR are in the second position, the on-off valve 44F
L, 44FR, 44RL, 44RR are controlled to be in the open state, and the on-off valves 46FL, 46FR, 46RL, 46
When the RR is controlled to the closed state (state shown), the wheel cylinders 38FL, 38FR, 38RL, 38RR
The control valves 40FL, 40FR, 40RL, 40RR and the connection conduits 48FL, 48FR, 48RL, 48RR communicate with the high-pressure conduit 32, thereby increasing the pressure in the wheel cylinder.

Conversely, control valves 40FL, 40FR, 40R
L, 40RR in the second position, the on-off valve 4
4FL, 44FR, 44RL, 44RR are closed and on-off valves 46FL, 46FR, 46RL, 46RR.
Is opened, the wheel cylinders 38FL, 38F
R, 38RL, 38RR are control valves 40FL, 40F
R, 40RL, 40RR and connecting conduits 48FL, 48
It communicates with the low-pressure conduit 42 via FR, 48RL, 48RR, thereby reducing the pressure in the wheel cylinder.

Further, the control valves 40FL, 40FR, 40R
When the on-off valves 44FL, 44FR, 44RL, 44RR and the on-off valves 46FL, 46FR, 46RL, 46RR are both closed in a situation where L, 40RR is in the second position, the wheel cylinders 38FL, 38FR, 38R are closed.
L, 38RR are blocked from both the high-pressure conduit 32 and the low-pressure conduit 42, so that the wheel cylinder 38F
The pressure in L, 38FR, 38RL, 38RR is maintained as it is.

As described above, the braking device 10 is controlled by the control valve 40F.
When L, 40FR, 40RL, 40RR are in the first position, the wheel cylinders 38FL, 38FR, 38FR
RL, 38RR, brake pedal 12 by driver
Generates a braking force in accordance with the amount of depression of the control valve.
When any of FL, 40FR, 40RL, and 40RR is in the second position, the on-off valves 44FL, 44
FR, 44RL, 44RR and open / close valve 46FL, 46
By opening and closing FR, 46RL, 46RR,
Regardless of the amount of depression of the brake pedal 12 and the braking force of another wheel, the braking force of that wheel can be controlled.

Control valves 40FL, 40FR, 40RL, 4
0RR, open / close valve 44FL, 44FR, 44RL, 44R
R and on-off valves 46FL, 46FR, 46RL, 46RR
Is controlled by the traction electronic control unit 50 as described in detail later.

Next, the acceleration slip control of the vehicle according to the first embodiment will be described with reference to the flowchart shown in FIG. FIG. 3 is a flowchart showing the processing content of the acceleration slip control device for the vehicle with the automatic transmission according to Embodiment 1 of the present invention. FIG. 9 is a characteristic diagram illustrating the relationship between the ratio of the front wheel speed to the vehicle speed and the steering angle.
FIG. 10 is a characteristic diagram illustrating the relationship between the fluid pressure and the fluid amount in a system including a wheel cylinder and its piping. FIG.
FIG. 6 is a characteristic diagram showing a relationship between a throttle opening and a judgment braking force. FIG. 12 is a characteristic diagram illustrating the relationship between the speed ratio, the torque ratio, and the capacity coefficient of the torque converter. In addition,
The control according to the flowchart shown in FIG. 3 is started by closing an ignition switch (not shown), and is repeatedly executed at predetermined time intervals.

First, in step S10, the gear position signal G_position and the like transmitted from each sensor and the AT electronic control unit 200 are read.
In step S20, left and right independent target wheel speeds Vti are calculated according to equation (1). Vti = MAX {VB · g (δ) / (1−λd), Vtmin} (1) where VB is the vehicle speed, and the average value of the driven wheel speeds = (VRL +
VRR) / 2 and λd are the target slip ratios.
2, g (δ) is a ratio to the vehicle speed of the inner and outer front wheels when steered, and is a characteristic as shown in FIG. 9 which is determined by the function of the steering angle δ and is substantially determined by the geometrical shape of the vehicle. MAX {x, y}
Represents a function in which the larger one of the arguments x and y is selected. Even if VB is close to 0, Vti is equal to or greater than a certain value.

In step S25, the deviation E between the target wheel speed Vti and the actual wheel speed Vi is calculated by the following equation (2). Ei = Vi−Vti (2)

FIG. 5 is a flowchart showing the processing content of step S30 in the first embodiment of the present invention. In step S30, the start and the end of the control according to the flow shown in FIG. 5 are determined. In step S31 of FIG. 5, this control is being controlled (flag F_CNTRL).
= 1), and if the control is not being performed, a deviation Ei indicating the slip state of the drive wheel is compared with a predetermined value ETRG (positive number) in step S33. The deviation Ei of one of the left and right wheels is large and the engine speed V
If E is larger than the predetermined value VEmin, and if the brake is in the non-stepping-on state (SB = 0), in step S35, a flag F_CNTRL is issued to start the control.
As a start process, the pump 34 is driven, and the on-off valves 44FL, 44FR are driven to switch the hydraulic circuit for the acceleration slip control, and the control valves 40FL, 4FL are controlled.
0FR is also driven, and the routine goes to the next step S40.

In step S33, if the deviation E is small, the flow shifts to the symbol A in FIG. On the other hand, if the control is being performed (flag F_CNTRL = 1) in step S31, it is determined in step S32 that the control is to be terminated. (SB = 1)
Terminates this control and sets the flag F_C in step S34.
The NTRL is cleared and the pump 34 is deactivated as a termination process, and the on-off valve 4 is returned to return the hydraulic circuit to normal.
6FL and 46FR are not driven, and the control valves 40FL and 4FR are not driven.
0FR is not driven, and subsequently, the on-off valves 44FL, 44FR
Is also not driven. Note that either Y1 or Y2 is Y
If it is greater than min, control is continued, and the flow moves to the next step S40.

In step S40, a corrected braking force ΔYi for making Vi equal to Vti is calculated according to the following equation (3). ΔYi = KI · Ei + KP · (Ei−Eli) + TD · (Vi−Vli) + ΔYli (3) where Eli, Vli and ΔYli are Ei and V, respectively.
i, ΔYi are values in the previous processing, and KI, K
P and TD each represent a weighting constant.

In step S60, the modified braking force Δ
To obtain Yi, open / close valve 44FL or 46FL, 4
Time (pulse width) TP for driving 4FR or 46RR
Compute i. FIG. 8 is a flowchart showing the processing content of step S60 in the first embodiment of the present invention. In FIG. 8, in step S61, it is checked whether or not the absolute value of ΔYi is equal to or more than the minimum value ΔYmin from the limit of the response of the on-off valve. If ΔYmin or more,
In step S65, ΔYli = the amount carried forward to the next time
0 and dividing the modified braking force ΔYi by the so-called braking efficiency coefficient KB, thereby increasing the wheel cylinder pressure increment ΔPi
Convert to Next, the fluid increase amount ΔQi corresponding to the pressure increase amount ΔPi is obtained from the fluid pressure-fluid amount characteristic f (P) of the brake system shown in FIG. 10, and Pi is calculated as Pi + Δ for the following calculation.
Pi, and the flow moves to step S80.

In step S80, the flow branches to a pressure increase calculation step S85 and a pressure decrease calculation step S82 based on the sign of the liquid increase amount ΔQi. In each step, the amount of increase ΔQ
The drive time of the on-off valve is obtained by dividing i by the flow rate from the orifice equation (flow rate∝the square root of the pressure difference before and after the orifice). In step S82, the hydraulic pressure of the low-pressure conduit 42 is set to 0.
When the pressure difference before and after the orifice is Pi, the coefficient determined by the shape and cross-sectional area of the orifice is C2, and the flow velocity is C
Since 2P1 / 2 is obtained, the drive pulse width TPi is given by the following equation (4).
Can be calculated by TPi = ΔQi / {(C2 · Pi ^1/2 ) −t2} (4) where t2> 0 is a dead time when driving the on-off valve 46FL or 46FR, and is a negative value because ΔQi is negative. Has been added.

Similarly, in step S85, the opening / closing valve 44FL or 4FL for increasing the pressure is given by the following equation (5).
The pulse width TPi for deactivating 4FR is calculated. TPi = ΔQi / [｛C1 · (Pa−Pi) ^1/2 ｝ + t1] (5) Here, t1 is a dead time of driving the on-off valve. On the other hand, if it is determined in step S61 that the corrected braking force ΔYi is small, the flow moves to step S62. Step S6
At 2, the corrected braking force ΔYi is substituted into ΔYli for the next time and is cleared to 0 and is not output, so the pulse width TP
i is also cleared to 0.

In step S100, the updated TPi
, A pulse is output to the target on-off valve. When the sign of TPi is positive, a pulse (off-pulse) for deactivating 44FL or 44FR is output for TPi time, and when the sign is negative, a pulse (on-pulse) for driving 46FL or 46FR is output as TPi. The time corresponding to the absolute value of is output. When TPi is 0, the open / close valve 44FL or 44
FR is a drive output, and 46FL or 46FR is in a non-drive state. However, only when this time TPi is 0, if the previous pulse output is not completed, the process is continued until the previous pulse output is completed.

In step S110, the estimated braking force Yi =
Yi + ΔYi is calculated. In step S120, A
A change instruction to be output to the T electronic control device 200 is determined. Here, an example of a shift instruction to set the lowest shift speed to the second speed will be described. 5 is a flowchart showing the processing content of step S120 in Embodiment 1 of the present invention. In FIG. 6, first, in step S121, whether or not the main control is being performed is checked with the flag F_CNTRL. If the control is being performed (F_CNTRL = 1), the flow moves to step S122, and the braking forces Y1 and Y2 of the left and right wheels are both
It is checked whether or not it is greater than a predetermined value YTRG as a judgment braking force.

The braking forces Y1 and Y2 are both at a predetermined value YTRG.
If it is larger, a shift instruction flag F_2nd for instructing the AT electronic control unit is set so that the shift control mode is a mode in which the lowest shift stage is the second speed. On the other hand, if both the braking forces Y1 and Y2 are smaller than the predetermined value YTRG,
The flow proceeds to the next step as it is. Predetermined value Y
TRG is a monotonically increasing function of the throttle opening θ as shown in FIG.

If it is determined in step S121 that control is not being performed (F_CNTRL = 0), the process proceeds to step S121.
At 125, the state of the shift instruction flag is checked. If F_2nd = 1 is satisfied in step S125, the flow shifts to step S126, where (F_2
nd = 0) Gear stage G at which the AT electronic control unit shifts
Check if _position is 2nd speed or higher. If it is determined in step S126 that the shift speed is the second speed or higher, the flow proceeds to step S128, and the shift instruction flag F_2nd is cleared. On the other hand, step S
At 126, if the shift speed is the first speed, the flow directly proceeds to the next step (NEXT). Also,
In step S125, the shift instruction F_2nd = 0
If (clear) is established, the flow directly proceeds to the next step (NEXT).

As described above, according to the acceleration slip control device for the vehicle with the automatic transmission according to the first embodiment of the present invention, the braking force increases when the power transmission path from the automatic transmission to the drive wheels and the supporting mechanism thereof increase. Thus, the effect that the acceleration slip control can be suitably performed without accompanying unpleasant vibration and without adding an engine generated torque control device accompanied by an increase in the number of parts and an increase in manufacturing cost can be obtained. Further, since the torque applied to the drive wheels can be reduced by controlling the shift of the automatic transmission without adjusting the torque generated by the engine, it is not necessary to add new parts for adjusting the torque generated by the engine. Suitable acceleration slip control can be realized by an inexpensive acceleration slip control device.

Embodiment 2 Next, a second embodiment of the present invention will be described in detail with reference to the accompanying drawings. FIG. 4 is a flowchart schematically showing control contents of an acceleration slip control device for a vehicle with an automatic transmission according to Embodiment 2 of the present invention. In addition, also in Embodiment 2,
Control according to the flow shown in FIGS. 1 and 2 is performed in the same manner as in the first embodiment.

The control according to the flowchart shown in FIG. 4 is started by closing an ignition switch (not shown) and is repeatedly executed at predetermined intervals. The same step symbols are given to portions performing the same float processing shown in FIG. 3 according to the first embodiment, and description thereof will be omitted. Step S1 different from the first embodiment below
30 and S140 will be described.

In step S110, the estimated braking force Y
After calculating i, in step S130, the drive torque Td is calculated by the following equation (6). Tni = 0.5Td-Yi (6) Here, Gj is a reduction ratio from the torque converter output to the drive wheels when the shift speed is j. Further, the torque ratio Kt and the capacity coefficient Kc are characteristics of the torque converter shown in FIG. 12, and the speed ratio e here is calculated by the following equation (7). e = VE / {0.5 (V1 + V2) Gj} (7) The net drive torque Tni for driving the drive wheels is calculated by the following equation (8). Tni = 0.5Td-Yi (8)

FIG. 7 is a flowchart showing the processing contents of step S140 in the second embodiment of the present invention. In step S140, as shown in the detailed flowchart of FIG. 7, an example of a shift instruction to set the minimum shift speed to the second speed as in the first embodiment will be described. First, in step S141, it is determined whether or not the main control is being performed by the flag F_C.
Check with NTRL. Under control (F_CNTRL =
If it is 1), the flow moves to step S142, and the braking forces Y1 and Y2 of the left and right driving wheels are changed to 1 for the automatic transmission.
It is checked whether or not the drive wheel torque decrease when the speed changes from the second speed to the second speed is larger than the reduction amount.

In step S142, if the braking forces Y1 and Y2 of the left and right driving wheels are both greater than the decrease in the driving torque, the braking forces Y1 and Y2 are adjusted so that the net driving force after the shift is the net value before the shift. Since the driving force can be prevented from decreasing, a shift instruction flag F_2nd for instructing the AT electronic control unit to set the shift control mode to the mode in which the lowest shift stage is the second speed is set. On the other hand, step S
At 142, if any one of the braking forces Y1 and Y2 of the left and right driving wheels is smaller than the decrease in the driving torque, the process directly proceeds to the next step.

If control is not being performed in step S141 (F
_CNTRL = 0), the flow moves to step S145, where the state of the shift instruction flag is checked, and F_2nd =
If it is 1, the flow moves to step S146, and normal (F_
In the control mode (when 2nd = 0), the AT electronic control unit checks whether the gear G_position at which the gear shifts is second speed or higher, and if it is second speed or higher, the flow proceeds to step S
The flow shifts to 148, where the shift instruction flag F_2nd is cleared. If it is the first speed, the flow directly shifts to the next step. Also,
If the shift instruction F_2nd = 0 in step S145, the process proceeds to the next step while keeping the clear state.

As described above, according to the acceleration slip control device for a vehicle with an automatic transmission according to the second embodiment of the present invention, the transmission to the drive wheels is performed by controlling the shift of the automatic transmission without adjusting the torque generated by the engine. Since the torque can be reduced,
It is not necessary to add a new component for adjusting the torque generated by the engine, and suitable acceleration slip control can be realized by a relatively inexpensive acceleration slip control device. Further, since it is possible to prevent a feeling of deceleration (decrease in acceleration) of the vehicle after changing the gear position, there is an effect that more suitable acceleration slip control can be performed.

[0047]

The acceleration slip device for a vehicle with an automatic transmission according to the present invention is generated when the vehicle with an automatic transmission starts or accelerates, which is interposed between the engine and the drive wheels and is automatically shifted by the shift control means. An acceleration slip control device configured to detect a slip of the drive wheel with respect to a road surface, and to suppress a slip of the drive wheel by a braking force adjusting unit that adjusts a braking force of the drive wheel based on the detection result. The braking force estimating means for estimating the braking force acting on the driving wheels based on the output signal of the first and second gears, and the shift control means for reducing the driving torque transmitted to the driving wheels based on the estimation result of the braking force estimating means. And a gear shift instructing means for giving an instruction.The power transmission path from the automatic transmission to the drive wheels and the supporting mechanism thereof cause an uncomfortable Without moving, also increases the number of components, without adding a torque control device for an engine with an increase in manufacturing cost, there is an advantage that it is suitably acceleration slip control.

In another embodiment of the present invention, an acceleration slip control device for a vehicle with an automatic transmission is provided between an engine and driving wheels, and is used to start a vehicle with an automatic transmission automatically shifted by a shift control means. Vehicle with an automatic transmission, wherein the slip of the drive wheel is suppressed by braking force adjusting means for detecting the slip of the drive wheel with respect to the road surface generated at the time of acceleration or acceleration and adjusting the braking force of the drive wheel based on the detection result. The braking force estimating means for estimating the braking force acting on the driving wheel based on the output signal of the braking force adjusting means, and the drive transmitted to the driving wheel based on the estimation result of the braking force estimating means. In order to reduce the torque, a calculation is performed based on a shift instruction means for giving a shift instruction to the shift control means, a driving torque transmitted from the engine to the driving wheels, and an estimation result of the braking force estimation means. A net driving torque calculating means for calculating a net driving torque as the difference between the estimated braking force,
When the net drive torque value estimated as a result of the adjustment by the braking force adjusting unit after the shift based on the shift instruction does not become smaller than the net drive torque value before the shift, the shift control unit transmits the drive torque to the drive wheels. And a shift instructing means for instructing a shift to reduce the shift. Therefore, it is possible to prevent a feeling of deceleration (decrease in acceleration) of the vehicle after a shift speed change. There is an effect that can be.

Further, the shift instructing means issues a shift instruction when the estimated braking force is larger than a predetermined braking force as a function of increasing the amount of depression of an accelerator pedal for adjusting the load condition of the engine. , Because the gear change conditions reflect the driver's willingness to accelerate,
There is an effect that a more harmonious acceleration slip control can be performed between the vibration suppression and the driver's intention to accelerate.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire configuration of a front wheel drive type vehicle to which an acceleration slip control device according to the present invention is applied.

FIG. 2 is a diagram schematically showing a configuration of a vehicle braking device according to Embodiment 1 of the present invention.

FIG. 3 is a flowchart showing processing contents of an acceleration slip control device for a vehicle with an automatic transmission according to Embodiment 1 of the present invention.

FIG. 4 is a flowchart schematically showing control contents of an acceleration slip control device for a vehicle with an automatic transmission according to Embodiment 2 of the present invention.

FIG. 5 is a diagram illustrating a step S according to the first embodiment of the present invention;
It is a flowchart which shows the processing content of 30.

FIG. 6 is a diagram illustrating a step S according to the first embodiment of the present invention;
12 is a flowchart showing the processing contents of step S120.

FIG. 7 is a diagram illustrating a step S according to the second embodiment of the present invention;
14 is a flowchart showing the processing contents of 140.

FIG. 8 is step S in the first embodiment of the present invention.
60 is a flowchart showing the processing contents of Step 60.

FIG. 9 is a characteristic diagram illustrating a relationship between a ratio of a front wheel speed to a vehicle body speed and a steering angle.

FIG. 10 is a characteristic diagram illustrating a relationship between a fluid pressure and a fluid amount in a system including a wheel cylinder and its piping.

FIG. 11 is a characteristic diagram showing a relationship between a throttle opening and a determination braking force.

FIG. 12 is a characteristic diagram illustrating a relationship between a speed ratio, a torque ratio, and a capacity coefficient of a torque converter.

[Explanation of symbols]

1 engine, 3 automatic transmission, 5 differential, 8 brake switch, 9 accelerator pedal, 10 brake,
12 brake pedal, 14 master cylinder, 18,
20, 26, 28 Brake oil pressure control device, 34 oil pump, 38FL, 38FR, 38RL, 38RR
Wheel cylinder, 40FL, 40FR, 40RL, 4
0RR control valve, 44FL, 44FR, 44RL, 44
RR open / close valve, 46FL, 46FR, 46RL, 46RR
On-off valve, 50 traction electronic control unit, 60 throttle opening sensor, 61 engine speed sensor,
62 transmission output shaft rotation speed sensor, 64FL to 64R
R Wheel speed sensor, 65 steering angle sensor, 66 pressure sensor, 200 AT electronic control unit.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI F16H 59:66

Claims (3)

[Claims] 1. A method for detecting slippage of a drive wheel with respect to a road surface which occurs when a vehicle with an automatic transmission that is interposed between an engine and a drive wheel and that automatically shifts by a shift control means when the vehicle starts or accelerates is detected. Based on the result, in an acceleration slip control device configured to suppress the slip of the driving wheel by a braking force adjusting unit that adjusts a braking force of the driving wheel, based on an output signal of the braking force adjusting unit, Braking force estimating means for estimating the acting braking force; and shift instructing means for instructing the shift control means to perform a shift instruction to reduce the driving torque transmitted to the drive wheels based on the estimation result of the braking force estimating means. An acceleration slip control device for a vehicle with an automatic transmission, comprising: 2. A method according to claim 1, further comprising detecting a slip of the drive wheel on the road surface which occurs when the vehicle with the automatic transmission is interposed between the engine and the drive wheel and is automatically shifted by the shift control means when the vehicle starts or accelerates. Based on the result, in an acceleration slip control device configured to suppress the slip of the driving wheel by a braking force adjusting unit that adjusts a braking force of the driving wheel, based on an output signal of the braking force adjusting unit, Braking force estimating means for estimating the acting braking force; and shift instructing means for instructing the shift control means to perform a shift instruction to reduce the driving torque transmitted to the drive wheels based on the estimation result of the braking force estimating means. And calculating a net drive torque as a difference between the drive torque transmitted from the engine to the drive wheels and the estimated braking force calculated based on the estimation result of the braking force estimation means. A net drive torque calculating means, and after the shift based on the shift instruction, when the net drive torque value estimated as a result of adjustment by the braking force adjusting means does not become smaller than the net drive torque value before the shift. An acceleration slip control device for a vehicle with an automatic transmission, characterized in that the shift control means includes shift instruction means for issuing the shift instruction to reduce the driving torque to the drive wheels. 3. The shift instruction means issues a shift instruction when the estimated braking force is larger than a predetermined braking force as a function of increasing an accelerator pedal depression amount for adjusting an engine load state. The acceleration slip control device for a vehicle with an automatic transmission according to claim 1.