JPS6299517A - Skid controller for vehicle - Google Patents

Abstract

PURPOSE:To effectively control the skidding of vehicle by a method in which the output of engine is regulated on the basis of a set value for the acceleration of vehicle during the early period of the acceleration but on the basis of a set value for slipping rate during the latter period. CONSTITUTION:At a step S1, a vehicle is started, and at a step S2, whether the vehicular speed is slower than a set speed V or not is judged. When the speed is slower than the speed V, operation moves from the step S2 to a step S3, and from the step S3 to a step S4 to control the control actuator of brake. At a step S5, the pressure of brake is held. At a step S6, the acceleration of rotation is judged, and at a step S8, the brake actuator is controlled to reduce the pressure of braking liquid. In the early period of acceleration, skidding is quickly controlled, and in the latter period, the skidding is accurately controlled.

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 drive wheels when a vehicle starts or accelerates, there is a problem that the vehicle cannot start or accelerate smoothly.

For this reason, a control device has been proposed that controls the engine output to control the skid of a vehicle when starting or accelerating (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 perform skit control more effectively.

(Structure of the Invention) Therefore, the present invention has the following features, as shown in FIG.
a rotational speed detection means R that detects the rotational speed of the driving wheel and the driven wheel; a rotational acceleration detection means G that receives the detection signal of the rotational speed detection means R and detects the rotational acceleration of the driving wheel;
Slip ratio detection means S receives the detection signal of the rotational speed detection means and detects the slip ratio of the drive wheels; and engine output adjustment means E receives the control signal and adjusts the control amount of the engine output control means. Then, the detection signals of the rotational acceleration detection means G and slip ratio detection means S are input, and the engine output control means is controlled based on the detection signal of the rotational acceleration detection means G at the early stage of acceleration, while at the latter stage of acceleration. The present invention is characterized by comprising control signal output means C for outputting a signal for controlling the engine output control means to the engine output adjustment means E based on the detection signal of the slip ratio detection means S.

(Effects of the Invention) According to the present invention, the engine output is adjusted based on the set value of the wheel acceleration in the early stage of acceleration, and the engine output is adjusted based on the set value of the slip ratio in the late stage of acceleration. Therefore, the skid can be quickly converged in the early stages of acceleration, and the skid can be precisely converged in the latter stages of acceleration, resulting in improved convergence stability.

(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 wheels P1. ,
.

A rotation speed detection sensor (rotation speed detection means R) for detecting rotation speed for Ffl 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 the accelerator sensor 12 that detects the amount of depression of the accelerator pedal 11 is input to the microcomputer 9, and a throttle control motor (engine output adjustment means E)+3 is driven by a control signal output from the microcomputer 9h). As a result, the amount of opening and closing of the throttle valve (engine output control means port 5) provided in the intake passage 14 is adjusted.

A master cylinder 22 linked to the brake pedal 21 is connected to an anti-lock monoulator 23 controlled by a microcomputer 9, and the anti-lock modulator 23 includes a hydraulic pump 25 driven by a motor 24. ．． A reservoir 26° accumulator 27 and the like are provided, and when the brake pedal 21 is depressed, the drive wheel FL,
Brake hydraulic pressure is supplied to the brakes 7.8 of the driven wheels flL and Rr (via the brakes 5 and 6 of the FR and the proportional pressure reducing valve 28.29. A rotational acceleration detection means G inputs the detection signals of the speed detection sensors 1 to 4 and detects the rotational acceleration of the drive wheels FL and PR; The detection signals of the slip rate detection means S for detecting the slip rates of FL and FR, the rotational acceleration detection means G and the slip rate detection means S are input, and the throttle control motor 13 and the brake control actuator (brake hydraulic pressure Adjustment means B)3
A control signal output means C for outputting a control signal to the control signal 1 is built-in.

On the other hand, the brake control actuator 31 is
Cylinder 32 for L and cylinder 33 for right driving wheel F'R
and each cylinder 32.33 has a piston 34.3.
5 is a brake hydraulic 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, 33b are provided with:
Control hydraulic pressure ports 32e and 33e are provided.

The pistons 34.35 are urged toward the control hydraulic pressure chambers 32b and 33b by springs 36 and 37. , 35 are linked with valves 40, 41 which are urged toward the brake hydraulic pressure chambers 32a, 33a by springs 38, 39.

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, PR.

Control hydraulic pressure inlet/outlet 32e of the control hydraulic pressure chambers 32b, 33b
, 3.3e 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 and 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 piston 34.35 is supplied to the control hydraulic pressure chambers 32b, 33b from the control hydraulic pressure inlet/outlet 32e, 3.3c via the brake hydraulic pressure chambers 32a, 33a through the biasing force of the spring 36.37. (Moved to fill, valve 36.3
7 is pushed by a spring 38, 39 to close the brake fluid pressure inlets 32c, 33c, and then, in response to the control fluid pressure acting on the piston 34, 35, the brake fluid pressure outlet 32d.

Brake hydraulic pressure is supplied from 33d to the brakes 5.6 of the drive wheels PL and PR.

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 to check valve 42c.

43C1 Reservoir 2 through orifices 42d, 43d
It will be reverted to 6.

Therefore, the driving wheels FL and PR 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.

” In a two-leg configuration, when the accelerator pedal 11 is depressed, the accelerator sensor 12 detects the amount of depression, and the detection signal is sent to the microcomputer 9.
The throttle control motor I3 controls the opening and closing of the throttle valve I5 in accordance with the depression 1.
When the brake pedal 21 is depressed, brake fluid pressure is supplied from the master turn cylinder 22 to the brakes 7.8 of the driven wheels RL and RR via the proportional pressure reducing valves 28, 29 and the anti-lock modulator 23, and at the same time, the brake fluid pressure is supplied to the brakes 7.8 of the driven wheels RL and RR. It is supplied from the cylinder 22 to the brakes 5.6 of the drive wheels PL and Frt via the anti-lock modulator 23 and the brake control actuator 31, so that each brake 5 to 8 is controlled in accordance with the depression finger.

Next, a method of controlling the skid during acceleration, which is similar to when the vehicle starts, will be explained based on the flowchart shown in FIG.

FIG. 3 shows the relationship between the rotational speed of the drive wheels FL and PR, the vehicle speed, and the slip ratio.

FIG. 4 shows the rotational acceleration of drive wheels FL and FR.

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.

In FIG. 6(b), the microcomputer 9 controls ash.
The timing of opening and closing the throttle t□ by the throttle control motor 13 is shown.

(1) Skid control method using brake fluid pressure This control method is to rapidly increase the brake fluid pressure to a predetermined increase position when the rotational (wheel) acceleration exceeds a predetermined value a1 on the acceleration side. On the other hand, when the rotational (wheel) acceleration returns to the predetermined value a1, the brake fluid pressure is controlled to be gradually decreased.

It starts in step Sl, and in step S2 it is determined whether the vehicle speed is less than or equal to the set speed V, and if YES (or less),
In step S3, it is determined whether an acceleration (al) signal (FIG. 5(a)) is generated when the rotational acceleration exceeds a predetermined value a, and if NO, the end is reached, and if YES, In step S4, the microcomputer 9 controls the brake control actuator 3I to control the drive wheels FL, P.
R brake 5.6 brake fluid pressure at a constant gradient for a predetermined time 1. In step S5, the brake fluid pressure is maintained at the increased position (FIG. 6(a)).

Then, in step S6, it is determined whether the rotational acceleration has returned to the predetermined value a1 and the acceleration (a)) signal has disappeared, and Y
If ES, it is determined in step S7 whether or not the disappearance of the acceleration (al) signal indicates that the driver has stopped pressing down on the accelerator pedal 11. If YES, the vehicle will not run and the vehicle will end.

If No in step S7, the microcomputer 9 controls the brake control actuator 31 in step S8.
is controlled to gradually reduce the brake fluid pressure of the brakes 5.6 of the drive wheels FL, Fr (at a constant gradient) (FIG. 6(a)).

According to this control method, since the initial pressure increase of the brake fluid pressure can be set to a large value, the slip time can be shortened and the skid can be quickly brought to an end.

(2) Skid control method using engine output This control method adjusts the engine output based on the set value of rotational (wheel) acceleration at the early stage of acceleration, and adjusts the engine output based on the set value of the slip ratio at the later stage of acceleration. It controls to adjust the output.

It starts in step Sl, 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),
Since this is the initial stage of acceleration, the acceleration (a,) signal (Fig. 5(a)
)) has occurred, and if NO, the process ends; if YES, the microcomputer 9 controls the throttle control motor 13 in step S9.
The engine output is lowered by gradually decreasing the opening degree of the throttle valve 15 (FIG. 6(h)).

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

It is determined whether or not the acceleration (a,) signal has disappeared after returning to , and if YES, the cause of the disappearance of the acceleration (a,) signal in step S7 is that the driver stopped pressing the accelerator pedal [1]. It is determined whether or not the vehicle is running, and if YES, the vehicle will not run and the vehicle will end.

If NO in step S7, the throttle opening degree is maintained at the reduced position in step SIO.

Next, in step Sl+, the deceleration (bl) signal when the rotational acceleration reaches the predetermined value h1 on the deceleration side (Fig. 5(b)
) has occurred, and if YES, the microcomputer 9 controls the throttle control motor 13 in step S+2 to gradually increase the opening degree of the throttle valve I5 and increase the engine output.

If NO in step Sll, the process moves to step S+2 after the predetermined time T has elapsed.

On the other hand, if No (or higher) in step S2, it is in the latter stage of acceleration, so it is determined in step SI3 whether or not the acceleration signal (a,) has occurred, and if NO, step SI4
It is determined whether or not the slip rate 20% (S20) signal (Fig. 5 (C)) is generated, and if NO, the process ends.
If YES, in step S15, the microcomputer 9 controls the throttle control motor 13 to gradually decrease the opening degree of the throttle valve 15 and lower the engine output.

Then, step SIG has a slip rate of 10% (SIQ)
Determine whether the signal (Fig. 5(d)) has disappeared or not, and
If S, the microcomputer 9 is
The throttle control motor 13 is controlled to gradually increase the opening degree of the throttle valve I5 to increase the engine output.

According to this control method, the convergence of the skid can be performed quickly in the early stage of acceleration, and the convergence of the skid can be performed precisely in the latter half of the acceleration, so that the convergence stability is improved.

(3) Skid control method using brake fluid pressure and engine output In this control method, the rotational (wheel) acceleration is set to a predetermined value a on the acceleration side.
When the value exceeds 1, the brake fluid pressure is increased and the engine output is decreased at the same time, and when the rotational (wheel) acceleration returns to the predetermined value a1, the brake fluid pressure is decreased and the engine output is decreased at the same time. It is controlled so that the engine output is increased when the rotational (wheel) acceleration reaches a predetermined value on the deceleration side.

It starts in step Sl, and in step S2 it is determined whether the vehicle speed is less than or equal to the set vehicle speed V. If YES, (less than), the acceleration (al ) signal (FIG. 5(a)) is generated. If NO, the process ends; if YES, 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 PR brake 5.6 is increased at a constant gradient within a predetermined time t1, and in step S5, 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, it is determined whether the rotational acceleration has returned to the predetermined value a1 and the acceleration (al) signal has disappeared, and Y
If it is ES, it is determined in step S7 whether the cause of the disappearance of the acceleration (al) signal is the stoppage of depression of the driver's head accelerator pedal II, and if it is YES, the vehicle does not run and the end is reached.

If NO in step S7, step S8 and step
Move to SIO.

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

Simultaneously with step S8, in step SIO, the throttle opening is maintained at the reduced opening position of the throttle valve 15 in step S9.

Next, in step Sll, it is determined whether or not a deceleration (b,) signal is generated when the rotational acceleration reaches a predetermined value b1 on the deceleration side. If YES, the microcomputer 9 controls the throttle in step S12. The engine output is increased by controlling the motor 13 and gradually increasing the opening degree of the throttle valve 15.

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

According to this control method, since both the braking force and the rotational force applied to the wheels can be controlled simultaneously, there is an effect that skid lines can be quickly and stably converged.

[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. Figures 5(a) and 5(b) are diagrams showing the rotational acceleration of the driving wheels, and Figure 5(c) is a diagram showing the acceleration signal and deceleration signal, respectively.
5(d) is a diagram showing the slip ratio 20% signal and 10% signal, respectively, FIG. 6(a) is a diagram showing the supply/discharge tie of brake fluid pressure, and FIG. 6(b) ) is a diagram showing the throttle opening/closing timing, 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 rate detection Means, PL, PR...driving wheels, RL, RR...driven wheels.

Claims (1)

[Claims] (1) A control device that controls engine output to control skid of a vehicle during starting or acceleration, comprising a rotational speed detection means for detecting the rotational speed of a driving wheel and a driven wheel; A rotational acceleration detection means for inputting a detection signal to detect the rotational acceleration of the drive wheel; a slip rate detection means for inputting the detection signal of the rotational speed detection means to detect the slip rate of the drive wheel; and a control signal. is inputted to the engine output adjustment means for adjusting the control amount of the engine output control means, and the detection signals of the rotational acceleration detection means and slip ratio detection means are input, and the detection signal of the rotational acceleration detection means is input at the initial stage of acceleration. control signal output means for controlling the engine output control means based on the above-mentioned engine output adjustment means, and outputting a signal for controlling the engine output control means to the engine output adjustment means based on the detection signal of the slip ratio detection means in the latter half of acceleration. A vehicle skid control device comprising: