JPH05178180A - Controller for braking and driving force - Google Patents

Abstract

PURPOSE:To omit low pressure piping between a reservoir tank and a controller, and to improve pedal feeling in the controller for anti-skid brake and, traction. CONSTITUTION:A master cylinder 1 and a reservoir 7 are communicated to one another at the time of non-braking, while the communication between the master cylinder 1 and the reservoir 7 is shut at the time of braking, by a valve device 11. The pressure of an accumulator is regulated according to the pressure of a master cylinder at the time of anti-skid brake control, and the pressure of the accumulator is regulated to a predetermined level at the time of traction control, by the valve device 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a vehicle for controlling braking force and driving force of an automobile or the like to reduce or prevent slip between a wheel and a road surface and improve braking performance and acceleration performance of the vehicle. Available.

[0002]

2. Description of the Related Art Conventionally, an anti-skid brake device has been developed to prevent or reduce wheel slip during braking of a vehicle to reduce the braking distance of the vehicle. Similarly, a traction device has been developed that prevents slipping of wheels during acceleration of a vehicle and improves acceleration performance. Since all control the braking force of the wheels, it is considered to be configured with one control device.
As disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2-18150, when this type of device is operated as an anti-skid brake device, the pressure between the master cylinder and the wheel cylinder is increased by a pump and discharged to a reservoir. To adjust the braking force. When operating as a traction device, shut off between the master cylinder and the wheel cylinder, supply oil from the reservoir tank in the master cylinder, and increase or decrease the pressure of the wheel cylinder by pressurizing with a pump and discharging to the reservoir. , The driving force is adjusted.

[0003]

However, in the prior art, during traction control, the initial oil amount for pump suction is obtained from the reservoir tank of the master cylinder, and during antiskid brake control, the reservoir of the master cylinder is acquired. The tank and pump are closed. With such a configuration, it is necessary not only to insert the control device into the brake pipe between the master cylinder and the wheel cylinder but also to provide a low-pressure hose that connects the reservoir tank of the master cylinder to the control device. For this reason,
Extra cost for parts, mounting, assembly and design.

Further, in the prior art, since the master cylinder and the pump are communicated with each other during the anti-skid brake control, the pump-up flow generated by the pump flows back to the master cylinder, and pedal kickback to the brake pedal occurs. , Pedal shock occurs. Therefore, the pedal feel becomes poor.

Therefore, in the present invention, in a control device for performing anti-skid brake control and traction control, it is an object to omit the low pressure pipe between the reservoir tank of the master cylinder and the control device and to improve the pedal feeling. There is.

[0006]

Means used in the present invention for solving the above-mentioned problems are a pump; a reservoir connected to an input end of the pump; a hydraulic pipe connected to an output end of the pump; A master cylinder cut valve that is placed between the hydraulic pipe and the master cylinder and is closed during anti-skid brake control and traction control; connected to the hydraulic pipe, the reservoir, and the wheel cylinder, and does not perform anti-skid brake control and traction control The hydraulic pipe and the wheel cylinder are communicated with each other, and the wheel cylinder and the reservoir are disconnected from each other, and the hydraulic pipe and the wheel cylinder are connected and disconnected during anti-skid brake control or traction control, and between the hydraulic pipe and the reservoir. Controls switching between disconnection and communication Control valve; equipped with; the hydraulic pipes, said reservoir and connected valve means to the master cylinder
The valve means includes a housing having a first chamber, a second chamber, a third chamber, and a fourth chamber therein; a first port connected to the master cylinder and communicating with the first chamber; a second port connected to the master cylinder. A second port communicating with the chamber; a third port connected to the hydraulic pipe and communicating with the third chamber; a fourth port connected to the reservoir and communicating with the fourth chamber; the first port
It slides in the housing according to the pressure in the chamber, and when the pressure in the first chamber is less than or equal to a predetermined value, the second chamber communicates with the second port, and the third chamber communicates with the fourth chamber. , The second
The communication between the chamber and the fourth chamber is blocked, and when the pressure of a predetermined value or more is applied to the first chamber, the communication between the second chamber and the second port is blocked, and the third chamber and the fourth chamber. An oil passage communicating with the fourth chamber; an oil passage provided between the oil passage and the second chamber, the oil flowing from the oil passage to the second chamber when the pressure of the oil passage is a predetermined value or more. Is provided with a relief valve that allows the above flow.

[0007]

According to the above means, the piston allows the communication between the second chamber and the second port because the master cylinder pressure is low during normal non-braking which does not require anti-skid brake control and traction control. Therefore, the master cylinder and the reservoir communicate with each other. Further, the master cylinder cut valve opens, and the hydraulic pipe and the wheel cylinder communicate with each other. Since the master cylinder pressure is low, the wheel cylinders are not pressurized and the wheels are not braked.

When the brake pedal is depressed and the normal braking state is established, the pressure in the first chamber rises and the piston slides, cutting off the communication between the second chamber and the second port. Therefore, the master cylinder and the reservoir are shut off from each other. Further, the master cylinder cut valve opens, and the hydraulic pipe and the wheel cylinder communicate with each other. Therefore, the brake fluid flows from the master cylinder to the wheel cylinder, the wheel cylinder operates according to the brake pressure, and the braking force is applied to the wheels.

In the normal brake described above, when the wheels slip and anti-skid brake control is required, the master cylinder cut valve is closed. Since the pressure in the first chamber increases, the piston slides, and the communication between the second chamber and the second port is cut off. Therefore, the master cylinder and the reservoir are shut off from each other. Further, the communication between the third chamber and the fourth chamber is cut off. In this state, when the pressure in the hydraulic conduit becomes higher than the master cylinder pressure, the pressure in the third chamber increases, so that the piston slides and the third chamber and the fourth chamber communicate with each other. Therefore, the third port and the fourth port communicate with each other, the hydraulic pressure of the hydraulic pipe is discharged to the reservoir through the third port-third chamber-fourth chamber-second chamber-fourth port, and the hydraulic pressure in the hydraulic pipe is increased. Goes down. When the pressure in the hydraulic pipe falls below the master cylinder pressure, the piston returns and the communication between the third chamber and the fourth chamber is cut off again. The hydraulic pressure in the hydraulic piping is adjusted to be higher than the master cylinder pressure by a certain ratio, and rises and falls according to the master cylinder pressure.
By opening and closing the pump and the control valve, the pressure of the wheel cylinder can be adjusted and the braking force can be adjusted.

In the non-brake state, when the wheels slip during acceleration and traction control is required, the master cylinder cut valve is closed. Since the master cylinder pressure has dropped, the piston allows communication between the second port and the second chamber, shuts off communication between the second chamber and the fourth chamber, and
Allow communication between room and room 4. Therefore, the master cylinder and the reservoir communicate with each other. At the beginning of control,
The pump pumps oil from the master cylinder through the first port-second chamber-fourth port-reservoir.

Since pressure is applied to the hydraulic piping from the pump,
The pressure in the third chamber is increasing. When the pressure in the hydraulic pipe becomes higher than the pressure determined by the relief valve, the relief valve opens, and the oil in the hydraulic pipe becomes the third port-the third chamber-the fourth chamber-the oil passage-the relief valve-the second chamber-the fourth chamber. It flows through the port to the reservoir and reduces the pressure in the hydraulic piping. Therefore, the pressure applied to the wheel cylinder is adjusted to the pressure determined by the relief valve. By opening and closing the pump and the control valve, the pressure of the wheel cylinder can be adjusted and the driving force can be adjusted.

[0012]

Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 1, the master cylinder 1 is connected to a wheel cylinder 2 for driving wheels via a master cylinder cut valve 10 and an inlet valve 3. A return cut valve 5 is provided in parallel with the inlet valve 3. Also,
The wheel cylinder 2 is connected to the reservoir 7 via an outlet valve 4. The reservoir 7 stores the fluid when a pressure higher than a predetermined pressure is applied. Master cylinder cut valve 1
0, the inlet valve 3 and the outlet valve 4 are control valves whose opening and closing are controlled by the electronic control unit 12.

A hydraulic pipe 28, which is a line between the master cylinder cut valve and the inlet valve, is connected to the accumulator 8 via an accumulator cut valve 9. The accumulator cut valve allows the fluid to flow from the accumulator 8 to the hydraulic pipe 28, and blocks the reverse flow. The accumulator 8 is also connected to the output end of the pump 6. The input end of the pump 6 is connected to the reservoir 7. The pump 6 is driven by the electronic control unit 12 and delivers fluid from the reservoir 7 to the accumulator 8 to increase the pressure in the accumulator 8.

The above-mentioned hydraulic pipe is connected to the third port 11c of the valve device 11. The valve device 11 also includes a first port 11a and a second port 11b connected to the master cylinder 1 and a fourth port 11d connected to the reservoir 7.
have.

The detailed structure of the valve device 11 is shown in FIG. The inside of the housing 13 is a flange 13 having a hollow cylindrical thickness.
It is partitioned by a and the flange 13b. A piston 14 is formed in the housing 13 so as to penetrate through the hollow portions of the flanges 13a and 13b. In the space portion of the piston 14 on the left side of the flange 13a in the drawing, a substantially conical portion 14b is formed so as to face the left side portion of the flange 13a in the drawing. The piston 14 is also provided with a substantially conical portion 14 a on the flange 1 of the housing 13.
It is formed so as to face the right side portion of 3a in the drawing. In the space portion on the right side of the illustrated flange 13a of the piston 14, two-stage cylindrical portions 14c and 14d are formed. The diameter of the cylindrical portion 14c is the flange 13 of the housing 13.
The cylindrical portion 14c slides inside the flange 13b with a diameter substantially equal to that of b. An O-ring seals between the cylindrical portion 14c and the flange 13b. The diameter of the cylindrical portion 14d is substantially equal to the inner diameter of the housing 13, and the cylindrical portion 14d slides inside the right side portion of the housing 13 in the figure. Cylindrical part 14d
An O-ring seals between the housing 13 and the housing 13. The piston 14 is biased rightward in the figure by a first spring 18. With the above configuration, the inside of the housing 13 is
The end 14e of the piston 14 has a first chamber 22 on the left side in the figure, a second chamber 23 on the left side of the flange 13a in the figure, and a third chamber formed on the right side of the flange 13a in the figure and around a substantially conical portion 14b of the piston 14. 25 and the fourth chamber 24 in the hollow portion of the hollow cylindrical flange 13a. A chamber 29 is formed by the cylindrical portions 14c and 14d of the piston 14, the inner diameter of the housing 13 and the flange 13b, and the chamber 29 communicates with the atmosphere through the communication passage 13c.

A space 26 is opened inside the left side portion of the flange 14a of the piston 14 in the figure. The space 26 communicates with the fourth chamber 24 via the oil passage 21. The space 26 is provided with a relief valve 17 biased rightward in the drawing by a second spring 19 and a spring receiver 16 to shut off the space 26 from the oil passage 21. The space 26 is in constant communication with the second chamber 23 through the passage 27. Therefore, the relief valve 17
Prevents the flow of fluid from the second chamber 23 to the oil passage 21, and opens when the pressure in the oil passage 21 rises above the set pressure determined by the second spring 19 to open the second passage from the oil passage 21.
Allowing fluid to flow into chamber 23.

The above-mentioned first port 11a is provided in the first chamber 22,
The second port 11b and the fourth port 11d are in the second chamber 23.
The third port 11c is provided in the housing 13 so as to communicate with the third chamber 25.

A valve body 15 is provided at the left end of the piston 14 in the figure. The valve body 15 is biased to the left side in the figure by the second spring 19 described above. The tip portion 15 of this valve body 15
As shown in FIG. 3, b shuts off the communication between the second port 11b and the second chamber 23 when the piston 14 moves to the left in the drawing. Further, as shown in FIG. 2, when the piston 14 moves to the right in the figure, the tip portion 15b of the valve body 15 separates from the second port 11b and allows communication between the second port 11b and the second chamber 23. To do.

In FIG. 1, the electronic control unit 12 recognizes the state of the vehicle by a sensor (not shown) and determines whether anti-skid brake control and traction control are necessary. If the electronic controller 12 does not require anti-skid brake control and traction control,
The master cylinder cut valve 10 and the inlet valve 3 are opened, and the outlet valve 4 is closed. The electronic control unit 12
When it is determined that the anti-skid brake control and the traction control are necessary, first, the master cylinder cut valve 10 is driven to disconnect the master cylinder 1 from the hydraulic pipe 28. Then, the inlet valve 3 and the outlet valve 4 are opened and closed according to the state of the vehicle to supply the pressure from the accumulator 8 to the wheel cylinder 2 or release the pressure of the wheel cylinder 2 to the input end of the reservoir 7 or the pump 6. Then, the pressure supplied to the wheel cylinder 2 is adjusted, and the braking force by the wheel cylinder is adjusted.

With the above structure, the embodiment of the present invention operates as follows.

First, during normal non-braking that does not require anti-skid brake control and traction control, master cylinder 1 is connected to a reservoir tank in a master cylinder (not shown). Since the master cylinder pressure is low, the pressure in the first chamber 22 is low, and the first spring 18 urges the piston 14 to the right in the drawing, as shown in FIG. Therefore, the valve body 15 allows the communication between the second port 11b and the second chamber 23, and the master cylinder 1 and the reservoir 7 communicate with each other through the second port 11b-the second chamber 23-the fourth port 11d. To do. The electronic control unit 12 opens the master cylinder cut valve 10 and the inlet valve 3, and closes the outlet valve 4. The pump 6 is inactive. Therefore, the pressure in the wheel cylinder 2 flows to the master cylinder 1, and the wheel cylinder 2 is not pressurized, so that the wheels are not braked.

In the above state, when a brake pedal (not shown) is depressed and the normal braking state is established, a pressure difference is generated between the first chamber 22 and the third and fourth chambers. Further, since the diameter of the piston 14 facing the first chamber 22 is set to be larger than the diameter of facing the second chamber 22, when the pressure of the master cylinder 1 exceeds a predetermined value, the piston 14 moves leftward in the drawing.
It is urged to the position shown in FIG. Tip portion 15 of valve body 15
b cuts off the communication between the second port 11b and the second chamber 23. Therefore, the master cylinder 1 and the reservoir 7 are shut off from each other. The states of the master cylinder cut valve 10, the inlet valve 3, and the outlet valve 4 do not change. Therefore, the brake fluid flows from the master cylinder 1 to the wheel cylinder 4, the wheel cylinder 4 operates according to the brake pressure, and the braking force is applied to the wheels.

Further, in the above-mentioned normal brake, when the wheels slip and anti-skid brake control is required, the master cylinder cut valve 10 is closed. The master cylinder pressure increases according to the amount of brake operation by the driver. For this reason, the pressure in the first chamber 22 increases, and the piston 14 is urged in the left direction in the drawing to the position shown in FIG. The tip portion 15b of the valve body 15 is the second port 1
The communication between 1b and the second chamber 23 is cut off. Further, the substantially conical portion 14a of the piston 14 abuts on the right portion of the flange 13a in the figure, and blocks communication between the third chamber 25 and the fourth chamber 24. Therefore, the master cylinder 1 and the reservoir 7 are disconnected from each other, and the pressure of the hydraulic pipe 28 is applied to the third chamber 25.
Here, the pump 6 is driven and the hydraulic pressure is stored in the accumulator 8. Then, the inlet valve 3 and the outlet valve 4 are opened and closed according to the state of the vehicle, and the braking force by the wheel cylinder is adjusted. The piston 14 is biased to the left in the drawing, and the substantially conical portion 14 of the piston 14 is
Since b is away from the flange 13a, the fourth chamber 24 and the second chamber 23 have the same pressure, and the relief valve 17 does not function. In this state, when the pressure in the hydraulic pipe 28 increases by a certain ratio with respect to the master cylinder pressure, the piston 14 is urged to the right in the drawing, and the oil in the hydraulic pipe 28 is discharged from the third port 11c-the third chamber 25-the third. Since it flows to the reservoir 7 via the fourth chamber 24-the second chamber 23-the fourth port 11d, the pressure in the hydraulic pipe 28 is lowered. Therefore, the pressure applied to the wheel cylinder 2 is regulated at a pressure higher than the pressure of the master cylinder 1 by a certain ratio.

In the non-brake state, when the wheels slip during acceleration and traction control is required, the master cylinder cut valve 10 is closed. Since the master cylinder pressure has dropped, the piston 14 is urged to the right side in the figure as shown in FIG. Therefore, the second port 1
The 1b and the second chamber 23 are communicated with each other. Also, the piston 14
The substantially conical portion 14b contacts the left portion of the flange 13a in the figure and blocks the communication between the second chamber 23 and the fourth chamber 24, so that the master cylinder 1 and the reservoir 7 communicate with each other. Here, the pump 6 is driven and pressure is stored in the accumulator 8. At the beginning of control, the pump 6 pumps oil from the master cylinder 1 via the second port 11b, the second chamber 23, the fourth port 11d, and the reservoir 7. The electronic control unit 12 opens and closes the inlet valve 3 and the outlet valve 4 according to the state of the vehicle to adjust the braking force by the wheel cylinder. The pressure from the accumulator 8 is applied to the hydraulic pipe 28. Since the piston 14 is biased to the right side in the figure, the substantially conical portion 14a of the piston 14 is
Is separated from the right end of the flange 13a in the drawing, and the third chamber 25 and the fourth chamber 24 are communicated with each other. Therefore, the hydraulic pipe 2
8 communicates with the oil passage 21 through the third port 11c, the third chamber 25, and the second chamber 25. Here, when the pressure in the hydraulic pipe 28 becomes higher than the pressure determined by the second spring 19,
The relief valve 17 is opened, and the oil in the hydraulic pipe 28 is in the third port 11c-third chamber 25-fourth chamber 24-oil passage 21-space 2
6-Passage 27-Second chamber 23-Fourth port 11d is discharged to the reservoir 7, and the pressure in the hydraulic pipe 28 decreases. The pressure applied to the wheel cylinder 2 is the second spring 1
It does not rise above the pressure defined by 9.

In the above embodiment, the wheel cylinder is controlled by obtaining oil from the brake pipe output from the master cylinder 1 during traction control. Therefore, it is not necessary to provide a low pressure hose connecting the reservoir tank of the master cylinder to the control device. Therefore, the cost of parts, mounting, assembly, and design can be kept low.

Further, even during the anti-skid brake control, the master cylinder and the pump are disconnected from each other.
The pump-up flow generated by the pump does not flow back to the master cylinder, and the pedal feel does not deteriorate.

[0028]

As described above, in the present invention, only the brake pipe is present between the master cylinder and the control device, and there is no low pressure pipe for connecting the reservoir tank of the master cylinder to the control device. Low cost.

Further, since the master cylinder and the pump are disconnected during the anti-skid brake control, there is no pedal kickback and the feeling is high.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a control device according to an embodiment of the present invention.

2 is a cross-sectional view of the valve device of the control device of FIG.

3 is a sectional view showing the operation of the valve device of FIG. 2 during braking.

[Explanation of symbols]

 1 master cylinder 2 wheel cylinder 3 inlet valve 4 outlet valve 5 return cut valve 6 pump 7 reservoir 8 accumulator 9 accumulator cut valve 10 master cylinder cut valve 11 valve device 11a 1st port 11b 2nd port 11c 3rd port 11d 4th port 12 Electronic control device 13 Housing 13a, b Flange 13c Communication passage 14 Piston 14a, b Substantially conical part 14c, d Cylindrical part 14e End part 15 Valve body 15b Tip part 16 Spring receiver 17 Relief valve 18 First spring 19 Second spring 20 stopper 21 oil passage 22 first chamber 23 second chamber 24 fourth chamber 25 third chamber 26 space 27 passage 28 hydraulic piping 29 chamber

Claims (1)

[Claims] 1. A pump; a reservoir connected to an input end of the pump; a hydraulic pipe connected to an output end of the pump; arranged between the hydraulic pipe and a master cylinder, during antiskid brake control and traction control. Master cylinder cut valve to be closed; connected to the hydraulic pipe, the reservoir and the wheel cylinder, communicates the hydraulic pipe and the wheel cylinder when anti-skid brake control and traction control are not performed, and shuts off between the wheel cylinder and the reservoir At the same time, during anti-skid brake control or traction control, a control valve for controlling switching between communication and cutoff between the hydraulic pipe and the wheel cylinder and cutoff and communication between the hydraulic pipe and the reservoir; the hydraulic pipe, the reservoir and the master cylinder. Connected to A valve means; the valve means includes a housing having a first chamber, a second chamber, a third chamber and a fourth chamber therein; a first port connected to the master cylinder and communicating with the first chamber; a master cylinder Second port connected to the second chamber and communicating with the second chamber;
A third port communicating with the chamber; a fourth port connected to the reservoir and communicating with the fourth chamber; sliding in the housing according to the pressure in the first chamber, and the pressure in the first chamber is equal to or less than a predetermined value At this time, the second chamber and the second port are communicated with each other, the third chamber and the fourth chamber are communicated with each other, the communication between the second chamber and the fourth chamber is cut off, and the first chamber is predetermined. A piston for disconnecting the communication between the second chamber and the second port and connecting the third chamber and the fourth chamber when a pressure equal to or higher than a value is applied; an oil passage communicating with the fourth chamber; the oil passage And a relief valve that is provided between the second chamber and allows the flow of oil from the oil passage to the second chamber when the pressure in the oil passage is equal to or higher than a predetermined value. Force control device.