JPS62101852A - Skid control device for vehicle - Google Patents

Abstract

PURPOSE:To enable the skid control to be effected depending on the gripping force of driving wheels by lowering the engine output as a wheel acceleration exceeds a specified value in the increasing side, and furthermore by minimizing the engine output as the wheel acceleration exceeds another specified valve beyond the previous specified one. CONSTITUTION:Each of revolving speed sensors (R) 1-4 is provided to each of front driving wheels FL and FR, and rear driving wheels RL and RR, and outputs detected by these sensors are inputted into a microcomputer 9. The microcomputer 9 controls a brake control actuator 31 such that braking pressure to brakes 5 and 6 of the driving wheels FL and FR is increased as a rotating (wheel) acceleration exceeds a specified value a1 in the increasing side, furthermore the opening of a throttle valve 15 is gradually decreased with a throttle control motor 13 actuated so as to lower the engine output. Besides, the throttle valve 15 is fully closed so as to minimize the engine output as the acceleration exceeds the second specified value a1.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a skid control device for a vehicle.

(Prior Art) When an excessive driving force is instantaneously applied to the driving wheels when starting or accelerating a vehicle, there is a problem that the vehicle cannot start or accelerate smoothly.

For this reason, a control device has been proposed that controls engine output to control skids during starting or acceleration (see Japanese Patent Laid-Open No. 59-68537).

(Object of the invention).

The present invention devises the control timing of the engine output,
The purpose is to control skids more effectively.

(Structure of the Invention) Therefore, as shown in FIG. 1, the present invention includes a rotational speed detection means R for detecting the rotational speed of the drive wheel;
A detection signal of the rotational speed detection means R is input, and when the rotational acceleration of the drive wheel reaches a first predetermined value on the speed increasing side, a first detection signal is output, and when the rotational acceleration exceeds the first predetermined value, the rotational acceleration increases. rotational acceleration detection means G that outputs a second detection signal when the rotational acceleration increases and reaches a second predetermined value; and engine output adjustment means E that inputs a control signal and adjusts the control amount of the engine output control means. , the detection signal of the rotational acceleration detection means G is input, and when the first detection signal is input, the engine output control means is controlled in a direction to decrease the output, while when the second detection signal is not input, the engine output control means is controlled to decrease the output. 1. A control signal output means C that performs a reduction control until the engine output returns to a predetermined value, and outputs a signal for reducing the engine output to the minimum output adjustment position when a second detection signal is input to the engine output adjustment means E. It is characterized by:

(Effects of the Invention) According to the present invention, when the wheel acceleration reaches the first predetermined value on the acceleration side, the engine output is reduced and the wheel acceleration reaches the first predetermined value.
Since the engine output is minimized when the predetermined value is exceeded and the second predetermined value is reached, appropriate skid control can be performed in accordance with the grip force of the driving wheels.

(Embodiments) Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 2, the front drive wheel FL of the automobile.

Rotation speed detection sensors (rotation speed detection means R) 1 to 1 detect rotation speeds for PR and rear driven wheels RL and RR.
4 and brakes 5 to 8 are respectively provided, and detection signals from each rotational speed detection sensor 1 to 4 are input to a microcomputer 9 mounted on the vehicle.

A detection signal from an accelerator sensor 12 that detects the amount of depression of the accelerator pedal 11 is input to a microcomputer 9, and a throttle control motor (engine output adjustment means E) 13 driven by a control signal output from the microcomputer 9 controls the intake air. The opening/closing amount of a throttle valve (engine output control means) 15 provided in the passage 14 is adjusted.

A master cylinder 22 linked to the brake pedal 21 is connected to an anti-lock modulator 23 controlled by a microcomputer 9, and the anti-lock modulator 23 has a hydraulic pump 25. driven by a motor 24. Reservoir 26. An accumulator 27 etc. is provided, and when the brake pedal 21 is depressed, the driving wheel FL,
Brake hydraulic pressure is supplied to the brakes 7.8 of the driven wheels r (L and RR) via the PR brake 5.6 and the proportional pressure reducing valve 28.29.

The microcomputer 9 includes a rotational acceleration detection means G that inputs the detection signals of the rotational speed detection sensors 1 to 4 and detects the rotational acceleration of the drive wheels FL and PR, and A slip rate detection means S receives a detection signal and detects the slip ratio of the drive wheels FL and PR, and a detection signal of the rotational acceleration detection means G and slip rate detection means S is input and the throttle control motor 13 and A control signal output means C for outputting a control signal to '31 is built-in.

On the other hand, the brake control actuator 31 controls the left driving wheel F.
It includes a cylinder 32 for L and a cylinder 33 for right driving wheel FR, and each cylinder 32.33 has a piston 34.35.
The brake fluid pressure chamber 32a.

33a and control hydraulic pressure chambers 32b, 33b, and the brake hydraulic pressure chambers 32a, 33a have brake hydraulic pressure inlets 32c, 33c and a brake hydraulic pressure outlet 32d.

33d, and the control hydraulic pressure chambers 32b, 32b are provided with:
Control hydraulic pressure ports 32e and 33e are provided.

The pistons 34, 35 are urged toward the control hydraulic pressure chambers 32a, 33a by springs 36, 37, and the pistons 34, 35 are urged toward the brake hydraulic chambers 32b, 33b by springs 38, 39. associated valves 40,41.

When the control hydraulic pressure is not acting on the control hydraulic pressure chambers 32b and 33b, the pistons 34 and 35 are moved by the spring 36.
．． 37, the valve 4 is moved to the control hydraulic pressure chambers 32b and 33b.
0.41 is pulled by the pistons 34 and 35 to open the brake fluid pressure inlets 32c and 33c, so when the brake pedal 21 is depressed, the anti-lock modulator 23
The brake fluid pressure enters the brake fluid pressure chambers 32a, 33a from the brake fluid pressure inlets 32c, 33c through the brake fluid pressure outlet 32d.
, 33d to the driving wheels FL, FR.

Control hydraulic pressure inlet/outlet 32e of the control hydraulic pressure chambers 32b, 33b
, 33e is a pressure reducing electromagnetic switching valve 42b connected to the accumulator 27 of the anti-lock modulator 23 via the pressurizing electromagnetic switching valves 42a, 43a.

43b, respectively connected to the reservoir 26.

Then, when the pressurizing electromagnetic switching valves 42a, 43a are opened and the pressure reducing electromagnetic switching valves 42b, 43b are closed by a control signal from the microcomputer 9, the control fluid pressure from the accumulator 27 is transferred to the pressurizing electromagnetic switching valve 42a. , 43
The control hydraulic pressure is supplied to the control hydraulic pressure chambers 32b, 33b from the control hydraulic pressure inlet/outlet ports 32e, 33e via the brake hydraulic pressure chamber 3a, and the piston 34.35 is pushed against the urging force of the spring 36.
2a, 33a side, and the valves 36.37 are pushed by springs 38.39 to open the brake fluid pressure inlets 32c, 33c.
The brake fluid pressure outlets 32d, 3 then close depending on the control fluid pressure acting on the pistons 34.35.
Brake fluid pressure is supplied from 3d to the brakes 5.6 of the front drive wheels PL and FR.

Conversely, the pressurizing electromagnetic switching valves 42a and 43a are closed,
When the pressure reducing electromagnetic switching valves 42b and 43b are opened, the control hydraulic pressure in the control hydraulic pressure chambers 32b and 33b is changed to the pressure reducing electromagnetic switching valve 4.
2b, 43b, the liquid is returned to the reservoir 26 via the check valves 42C143C1 orifices 42d, 43d.

Therefore, the driving wheels FL and FR can be controlled in two ways: by depressing the brake pedal 21 and by the brake control actuator 31 controlled by the microcomputer 9.
Braking will be performed by the brake system of the system.

Note that 44a and 45a are relief valves, and 44b and 45b are dampers.

With the above configuration, normally when the accelerator pedal 11 is depressed, the accelerator sensor 12 detects the amount of depression, the detection signal is processed by the microcomputer 9, and the throttle control motor 13 controls the throttle valve 15. is controlled to open and close depending on the amount of depression, while when the brake pedal 21 is depressed, brake fluid pressure is applied from the master cylinder 22 to the brakes 7 of the driven wheels RL and RR via the proportional pressure reducing valves 28, 29 and the anti-lock modulator 23. At the same time, it is supplied from the master cylinder 22 to the brakes 5.6 of the drive wheels FL and PR via the anti-lock modulator 23 and the brake control actuator 31, and each brake 5 to 8 is activated according to the amount of depression. Braking will be controlled.

Next, a method of controlling the skid at the time of starting or accelerating will be explained based on the flowchart shown in FIG.

FIG. 3 shows the rotational speed of the drive wheels FL and PR, and the vehicle speed. FIG. 4 shows the rotational acceleration of the drive wheels FL and PR.

FIG. 5 shows the timing of the acceleration signal detected by the rotational acceleration detection means G of the microcomputer 9.
) also show the timing of the deceleration signal.

FIG. 5(C) shows the timing of the 20% slip rate signal detected by the slip rate detection means S of the microcomputer 9, and FIG. 5(d) shows the timing of the 10% slip rate signal. There is.

FIG. 6(a) shows the timing of supply and discharge of brake fluid pressure by the brake fluid pressure control actuator 31 controlled by the microcomputer 9.

FIG. 6(b) shows the opening/closing timing of the throttle opening by the throttle control motor 13 controlled by the microcomputer 9. In FIG.

(1) This control method when the coefficient of friction (μ) between the road surface and the tires is low is basically a control method using brake fluid pressure and engine output, and the rotational (wheel) acceleration is on the acceleration side. When the brake fluid pressure exceeds a predetermined value a1, the engine output is simultaneously increased while the rotational (wheel) acceleration returns to the predetermined value al, the brake fluid pressure is decreased and the engine output is simultaneously decreased. is held at the decreasing position, and the engine output is controlled to be increased when the rotational (wheel) acceleration reaches a predetermined value b1 on the deceleration side.

It starts in step S1, and in step S2 it is determined whether the vehicle speed is less than or equal to the set speed V. If YES (hereinafter...initial acceleration), the rotational acceleration is set to a predetermined value a1 in step S3.
It is determined whether or not the acceleration (al) signal (Fig. 5 (a)) is generated when exceeding
If YES, the microcomputer 9 controls the brake control actuator 31 in step S4.
The brake fluid pressure of the brakes 5.6 of the driving wheels FL and PR is increased at a constant gradient within a predetermined time t1, and step S5
Then, the brake fluid pressure is maintained at the increased position (FIG. 6(a)).

Simultaneously with step S4, the microcomputer 9 controls the throttle control motor 13 in step S9 to gradually reduce the opening degree of the throttle valve 15 to lower the engine output (FIG. 6(b)).

Then, in step S6, the rotational acceleration reaches a predetermined value a.

It is determined whether the acceleration (al) signal has disappeared after returning to , and if YES, it is determined in step S7 whether or not the cause of the disappearance of the acceleration (a,) signal is the driver's stop pressing down on the accelerator pedal 11. If it is YES, the vehicle will not run and the vehicle will end.

If NO in step S7, the process moves to step S8 and step SIO.

In step S8, the microcomputer 9 controls the brake control actuator 31 to
The brake fluid pressure of the FR brake 5.6 is gradually decreased at a constant gradient (Fig. 6(a)).

Simultaneously with step S8, in step SIO, the throttle valve 15 is brought to the reduced opening position in step S9 to maintain the throttle opening.

Next, in step Sll, a deceleration (bl) signal (Fig. 5(b)
)) has occurred, and if YES, the microcomputer 9 controls the throttle control motor 13 in step S12 to gradually increase the opening degree of the throttle valve 15 and increase the engine output. .

If NO in step Sll, the process moves to step S12 after the predetermined time T has elapsed.

On the other hand, if No in step S2 (late stage of acceleration), it is determined in step S13 whether the acceleration (aυ times signal has occurred), and if NO, in step S14, the slip rate is set to 20% (S tO ) signal (Fig. 5 (C)) is generated or not, and if No, it is the end, and YES
If so, in step S15, the microcomputer 9 controls the throttle control motor 13 to gradually increase the opening of the throttle valve 15, and in step S16, the slip rate 10% (S,.) signal (FIG. 5(d)) ) has disappeared, and if YES, in step S12, the microcomputer 9 controls the throttle control motor 13 to gradually increase the opening degree of the throttle valve 15 and increase the engine output. .

(2) Skid control method when the coefficient of friction (μ) between the road surface and the tires is high This control method is basically a control method using engine output, and the wheel acceleration is set to a first predetermined value a1 on the acceleration side. , the engine output is reduced and the wheel acceleration exceeds the first predetermined value a1 to reach the second predetermined value a.

When this is reached, the engine output is controlled to a minimum.

Note that, below, a control method using brake fluid pressure will be explained at the same time.

It starts in step S1, and in step S2 it is determined whether the vehicle speed is less than or equal to the set vehicle speed V, and if YES (or less),
In step S3, it is determined whether or not rotational acceleration 1 (a) has occurred, and if No, the process moves to step S4 and step S9.

In step S4, the microcomputer 9 controls the brake control actuator 31 to control the drive wheels FL,
The brake fluid pressure of the FR brake 5.6 is increased at a constant gradient within a predetermined time t, and in step S5, the brake fluid pressure is maintained at the increased position (Fig. 6 (a)).
.

Simultaneously with step S4, the microcomputer 9 gradually decreases the opening degree of the throttle valve 15 in step S9 to lower the engine output (FIG. 6(b)).
.

On the other hand, in step S17, the rotational acceleration is set to a second predetermined value a,
It is determined whether the acceleration (a,) signal (Figure 5 (a)) is generated when the acceleration (a,) is exceeded, and if YES, step S
In step S18, the microcomputer 9 controls the brake control actuator 31 to further increase the brake fluid pressure of the brakes 5 and 6 of the drive wheels FL and FR at a constant gradient within a predetermined time t, and in step S20. , the brake fluid pressure is maintained at the increasing position H (see Fig. 6(a)
)).

Simultaneously with step 518, the throttle control motor 13 is controlled by the microcomputer 9 in step S19 to further gradually reduce the opening degree of the throttle valve I5 to lower the engine output, and in step S21 the throttle control motor 13 is controlled by the microcomputer 9. Set the opening degree to fully closed.

Then, in step S22, whether the rotational acceleration has returned to the predetermined value al and the acceleration (al) signal has disappeared, or whether the rotational acceleration has returned to the predetermined value a and the acceleration (a,) signal has disappeared. If YES, step S7
In step S7, it is determined whether or not the cause of disappearance of the acceleration (al or a2) signal is the driver's stop pressing down on the accelerator pedal 11. If YES, the vehicle will not run and the vehicle will end.◎ If NO in step S7, In step S8, the microcomputer 9 controls the brake control actuator 3.
I is controlled to gradually reduce the brake fluid pressure of the brakes 5.6 of the driving wheels FL and PR at a constant gradient (FIG. 6(a)).

Simultaneously with step S8, in step Sll, the deceleration (
b.) It is determined whether the signal (FIG. 5(b)) is generated, and if YES, the microcomputer 9 controls the throttle control motor 13 in step S12 to fully open the throttle valve 15. The engine output is gradually increased from the closed state.

If NO in step Sit, the process moves to step S12 after the predetermined time T has elapsed.

According to this control method, there is an effect that appropriate skid control can be performed according to the coefficient of friction between the road surface and the tires.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the present invention, Fig. 2 is a block diagram of a skid control device according to the present invention, Fig. 3 is a diagram showing the relationship between drive wheel rotational speed, vehicle speed, and slip ratio. 5(a) and 5(b) are diagrams showing the rotational acceleration of the driving wheels, and FIG. 6(b) is a diagram showing the timing of opening and closing the throttle, and FIG. 7 is a flowchart of the skid control method. B...Brake fluid pressure adjustment means, C...Control signal output means, E...Engine output adjustment means, G...Rotational acceleration detection means, R...Rotational speed detection means, S... Slip ratio detection means, PL, FR...driving wheels, RL, RR...driven wheels.

Claims (1)

[Claims] (1) A control device that controls skid of a vehicle during starting or acceleration by controlling engine output, comprising a rotational speed detection means for detecting the rotational speed of a drive wheel, and a detection signal of the rotational speed detection means. input, output a first detection signal when the rotational acceleration of the drive wheel reaches a first predetermined value on the speed increasing side, and the rotational acceleration increases beyond the first predetermined value;
rotational acceleration detection means for outputting a second detection signal when a second predetermined value is reached; and engine output adjustment means for inputting a control signal to adjust the control amount of the engine output control means;
When the detection signal of the rotational acceleration detection means is input and the first detection signal is input, the engine output control means is controlled in a direction to decrease the output, while when the second detection signal is not input, the engine output control means is controlled to reduce the output. It is characterized by comprising a control signal output means for controlling the engine output to decrease until the engine output returns to the value, and outputting a signal for controlling the engine output to decrease to the minimum output adjustment position when the second detection signal is input to the engine output adjustment means. Skid control device for vehicles with