JPH02219B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operating pressure supply device for anti-skid control of an anti-skid device used in a brake device of a vehicle or the like.

Conventional devices of this type include, for example, JP-A-53-
As shown in Japanese Patent No. 25771, there is provided a dynamic pressure supply device for anti-skid control that supplies working pressure fluid to a fluid pressure regulating device that adjusts the brake fluid pressure supplied to the wheel cylinder of a wheel boob in order to prevent skidding of the wheels. , comprising a hydraulic pump and a restriction valve provided in a pipe connected to a discharge port of the hydraulic pump to reduce the flow path area of the pipe and increase the pressure of the working pressure liquid discharged by the hydraulic pump, It is known that the hydraulic pressure regulating device is connected to the piping between a hydraulic pump and a restriction valve.

However, in the conventional system, the above working fluid pressure is
Since the pressure is to be increased in proportion to the pressure inside the brake system, some of the fluid discharged from the master cylinder is consumed to move the spool or piston inside the restriction valve, causing problems such as delay in brake operation. be.

The present invention has been made in view of the above-mentioned problems, and aims to provide a dynamic pressure supply device for anti-skid control that can prevent delays in brake operation.
A valve member that increases or decreases the flow path area of the piping, an elastic member that urges the valve member in a direction to increase the flow path area, and a negative pressure generated by driving the engine that has one end of the valve member and the other end of the valve member that biases the valve member in a direction to increase the flow path area. and a movable member that receives pressure and urges the valve member in a direction in which the flow path area decreases against the elastic member.

By doing this, when the force corresponding to the difference between the atmosphere acting on the movable member and the negative pressure generated by the engine drive becomes larger than the force due to the elastic member,
The valve member is moved so as to reduce the flow path area of the piping connected to the discharge port of the hydraulic pump, and the pressure of the working pressure fluid supplied to the hydraulic pressure regulating device is increased. Therefore, part of the fluid discharged from the master cylinder is not consumed in moving the valve member to increase the pressure of the working pressure fluid.

Hereinafter, the present invention will be explained in detail based on illustrated examples.

FIG. 1 is a diagram schematically showing an embodiment of the present invention, and FIG. 2 is a diagram showing details of a hydraulic pressure adjusting device including a brake system.

In FIG. 1, a dynamic pressure supply device for anti-skid control is indicated as a whole by 1, and the device 1
has a hydraulic pump 2 driven by the engine of the vehicle, the pump 2 having a pipe 5 connected to the outlet side of the pump 2 and the inlet 4 of the restriction valve 3;
Outlet 6 of restriction valve 3 and power steering device 7
The hydraulic pressure is sent to the limit valve 3 and the power steering device 7 by a pipe 8 connected to the inlet side of the , are connected to a hydraulic tank 13 through pipes 11 and 12.

The hydraulic pressure adjustment device 14 of the anti-skid device is disposed between the piping 5 and the piping 12, with the piping 15 shown by the broken line facing the inlet side of the device 14, and the piping 16 shown by the dashed line connecting the piping 5 to the inlet side of the device 14. , and the pipes 12 are connected to the drain port side of the device 14, respectively.

The restriction valve 3 has a spool 19 as a valve member movably accommodated in the inner hole 18 of the main body 17, and a groove 20 is formed in the right center part to accommodate the spool 19.
According to the movement of the groove 20, the passage area connecting the outlet 6, which communicates without limit with the groove 20, and the groove 21 in the inner hole 18, which communicates with the inlet 4 without limit, can be increased or decreased. The left and right sides of the right portion of the spool 19 communicate with the hydraulic tank 13 via drain ports 10 and 9, respectively. Further, the left portion of the spool 19 is a small diameter portion 22, and this small diameter portion 22 is tightly and slidably fitted into a small hole 23 of the main body 17.
The end portion is located within the response chamber 24 . The inside of the response chamber 24 is divided into an atmospheric chamber 26 and a negative pressure chamber 27 by a diaphragm 25 as a movable member, and the biasing force due to the difference in pressure acting on the left and right sides of the diaphragm 25 is applied to the small diameter portion 22. The integrated plate 28 acts to move the spool 19 to the left until its left end abuts the main body 17. 29 is a spring that biases the spool 19 to the right with the plate 28 interposed therebetween.

The atmospheric chamber 26 communicates with the outside air through the hole 30,
On the other hand, the negative pressure chamber 27 communicates with the intake manifold of the engine or a vacuum pump 33 (shown as a negative pressure source in the drawing) driven by the engine via a hole 31 and a pipe 32. A check valve 34 and a solenoid valve 35 for selectively communicating the negative pressure chamber 27 with the negative pressure source 33 and the outside air are provided.

The solenoid valve 35 is normally located at a position that communicates the negative pressure chamber 27 with the atmosphere, and is energized by a signal from a circuit not shown when the driver removes his or her foot from the accelerator pedal and the accelerator pedal returns to the non-depressed position. The negative pressure chamber 27 is operated to communicate with the negative pressure source 33.

To explain with reference to FIG. 2, the hydraulic pressure adjustment device 14 is provided in the middle of a pipe 38 that connects a brake tandem master cylinder 36 and a rear wheel brake device 37, and is connected to the pipe 38 in a substantially U-shape. In this passage 39, a tilt valve 42 which is opened by engaging with the end of a plunger 41 disposed in a chamber 40 on the master cylinder 36 side is inserted into a chamber 43 on the rear wheel brake device 37 side. The chamber 40 is provided so as to be able to prevent liquid movement in the direction from the device 37 to the master cylinder 36, and the chamber 40 is connected to the rear wheel brake device 37.
The open end of the through hole 44 communicating with the side and the plunger 41
A bypass valve 45 is formed in which the master cylinder 36 side and the rear wheel brake device 37 side can be directly communicated. Further, a check valve 46 is provided between the chamber 40 and the chamber 43 of the passage 39 to prevent the liquid from moving from the chamber 40 to the chamber 43.
The check valve 46 can be opened by coming into contact with a small diameter portion 49 of a piston 48, which is arranged to be able to increase or decrease the volume of a chamber 47 formed on the side of the rear wheel brake device 37 of the check valve 46. Further, the plunger 41 is located on the right side of the plunger 41 and is engaged with the inclined valve 42 so that the plunger 41 is engaged with the inclined valve 42.
A piston 50 is arranged to open the bypass valve and move the bypass valve 45 to a closed position, and the pressure supplied from the piping 5 acts on the right end side of the piston 50. There is.

Pressure from the piping 5 is selectively applied to the left end of the piston 48 via a solenoid valve 51 that is switched in response to a signal from an anti-skid control circuit (not shown). The chamber 52 on the left end side of 48 can be switched between the illustrated position where it communicates with the pipe 5 and the position where it communicates with the pipe 12.

In addition, in the hydraulic pressure adjustment device 14, 53,5
4 indicates atmospheric pressure communicating with the outside air, and a indicates an O-ring.

The master cylinder 36 includes a front wheel brake device 5.
5 are connected by piping 56, and brake pressure is generated in each system by a brake pedal 57. 58 is a brake pedal 57
This is a brake switch that changes when you press the button.

The effects of these embodiments will be described below.

Assuming that the vehicle is currently parked and the engine is not being driven, no negative pressure is being generated in the negative pressure source 33 and the pump 2 is not being driven. There is no pressure in each pipe. However, it is possible to apply the brakes even in this state.

After this state, when the driver or the like drives the engine, negative pressure starts to be generated in the negative pressure source 33, and the pump 2 is driven, causing liquid to flow into the pipe 5.
begins to be ejected.

At this time, since the access pedal is usually depressed when starting the engine, the solenoid valve 35 is
It is located at a position that communicates the negative pressure chamber 27 with the atmosphere, and the piping 5
There is no high pressure generated inside, but a relatively low pressure due to piping resistance, etc. This low pressure
The piping 15 acts on the right end side of the piston 50 and the left end side of the piston 48, and moves the plunger 41 to the position where the slope valve 42 is open and the bypass valve 45 is closed, and the piston 48 to the position where the check valve 46 is open.

Suppose that after passing through such a state, the brakes are applied while the vehicle is traveling at high speed.

Then, by first removing the foot from the accelerator pedal, the accelerator pedal returns to the non-depressed position, and the solenoid valve 35 is switched. Therefore, negative pressure is introduced into the negative pressure chamber 27, the spool 19 moves against the biasing force of the spring 29, the area of the passage connecting the grooves 20 and 21 decreases, and high pressure is generated on the groove 21 side. . This high pressure acts on the pistons 48, 50 via the pipe 15, opens the tilt valve 42 and check valve 46, and forces the bypass valve 45 closed.

In this state, the pressure fluid from the master cylinder 36 is
The brakes are supplied to the brake devices 37 and 54 without restriction to apply the brakes.

After the brakes are applied, if the rear wheels skid due to excessive braking force being applied,
The solenoid valve 5 is controlled by a signal from a control circuit (not shown).
1 is activated, the chamber 52 is switched to communicate with the hydraulic tank 13, and the piston 48 begins to move to the left due to the brake pressure in the chamber 47, closing the check valve 46 and reducing the volume of the chamber 47. is increased to reduce the pressure supplied to the rear wheel brake device 37 and bring the wheels out of the skid state.

When the wheels come out of the skid state, solenoid valve 5
1 is switched again to communicate the chamber 52 with the pipe 15 side, and the piston 48 begins to move to the right, increasing the pressure on the rear wheel boogie device 37 side.

Thereafter, the piston 48 repeatedly moves left and right depending on the condition of the wheel, thereby preventing the rear wheel from skidding.

When the necessary brake is applied, master cylinder 3
6 to the non-operating position, and each brake device 3
Release the pressure supplied to 7,55.

Thereafter, when the driver depresses the accelerator pedal again to increase the traveling speed of the vehicle, the solenoid valve 35 is switched to the illustrated position and the negative pressure chamber 27 is communicated with the outside air. Then, the spool 19 moves to the right due to the biasing force of the spring 29, and the pressure inside the pipe 5 decreases to a low pressure.

After that, if you want to apply the brake, each time you take your foot off the access pedal and return the accelerator pedal to the non-depressed position, the spool 19 will move into the negative pressure chamber 2.
Due to the negative pressure of 7, the hydraulic pressure adjusting device 1 is switched to a position where the passage area connecting the grooves 21 and 20 is reduced.
4 is supplied with high pressure for control.

On the other hand, due to some reason, such as a failure of the pump 2 or damage to the piping 5, the spool 19 may become stuck in the groove 2.
If high pressure is not generated in the pipe 5 even though the area of communication between the plunger 40 and the groove 21 is reduced, the plunger 41 receives the brake pressure in the chamber 40 and moves to the right. Bypass valve 4
5 is opened, and the inclined valve 42 is closed. Furthermore, when the pressure within the chamber 47 increases slightly, the check valve 46 closes by moving the piston 48 to the left. Therefore, brake pressure is supplied to the rear wheel brake 37 through the bypass valve 45.

In the above-described embodiment, in supplying the dynamic pressure for anti-skid control to the hydraulic pressure regulator 14, the pressure starts to increase when the foot is removed from the access pedal and the accelerator pedal returns to the non-depressed position. , the pressure is sufficiently increased before anti-skid control starts when the brakes are applied,
Part of the fluid discharged from the master cylinder 36 is not wasted, and the rear wheel brake 37
The brake can be applied quickly.

As is clear from the above description, according to the present invention, the pressure of the operating pressure fluid supplied to the fluid pressure adjustment device can be increased.
Since this is done by using the negative pressure generated by the engine, part of the fluid discharged from the master cylinder is not consumed to increase the pressure of the hydraulic fluid, which has the effect of preventing delays in braking action. However, the present invention can be practiced without being limited to the illustrated example.

That is, in the illustrated example, the solenoid valve 35 is operated in response to the return operation of the access pedal to introduce negative pressure into the negative pressure chamber 27, but the engine is driven without the solenoid valve 35. Negative pressure may be introduced into the negative pressure chamber 27 at all times. In this case, a throttle passage is provided that constantly communicates the negative pressure chamber 27 with the outside air, and the throttling effect of this throttle passage is maintained when the engine is driven. While the spool 19 is in the negative pressure chamber 27
If the negative pressure is maintained at a position where the communication area between the grooves 20 and 21 is reduced, atmospheric air will be introduced into the negative pressure chamber 27 when the engine is stopped.
The spool 19 is in a position moved to the right. In addition, when using the solenoid valve 35, an example in which the solenoid valve 35 is activated when it detects that the driver is in the vehicle instead of being activated in response to the return operation of the accelerator pedal;
Examples include switching the ignition switch, in other words, operating it in response to an attempt to start the engine, and further examples in which it operates in response to the operation of a brake light switch. It may also be operated by In short, in the present invention, the negative pressure generated in the intake manifold of the engine due to engine drive, or the negative pressure generated in the vacuum pump driven by the engine, is used to move the spool. Instead of using the brake pressure to move the spool, the pressure to be supplied to the hydraulic pressure regulating device may be generated.

In the present invention, the timing to start generating the pressure to be supplied to the hydraulic pressure regulating device can be done independently of the generation of brake pressure, but is at the latest at the same time as the brake pressure starts to be generated, or at the latest. Preferably, the pressure is increased to a level at which anti-skid control can be performed at the point when brake pressure starts to be generated, and
From the viewpoint of pump durability, etc., the timing of occurrence shown in the examples is particularly good.

[Brief explanation of drawings]

1 is a diagram schematically showing an embodiment of the present invention,
FIG. 2 is a diagram showing details of the hydraulic pressure adjustment device including the brake system. 1...Dynamic pressure supply device for anti-skid control, 2
...Liquid pump, 3...Restriction valve, 5, 8...Piping, 19
...Spool, 24...Response chamber, 25...Diaphragm, 26...Atmospheric chamber, 27...Negative pressure chamber, 29...Spring.

Claims (1)

[Claims] 1. An anti-skid control working pressure supply device that supplies working pressure fluid to a hydraulic pressure regulating device that adjusts the brake fluid pressure supplied to the wheel cylinder of a wheel brake in order to prevent wheel skidding, which comprises a hydraulic pump, and a hydraulic pump. a restriction valve provided in a pipe connected to a discharge port of the hydraulic pump to reduce the flow path area of the pipe and increase the pressure of the working pressure liquid discharged by the hydraulic pump; In the one connected to the piping between the pressure pump and the restriction valve,
The restriction valve includes a valve member that increases or decreases the flow path area of the piping, an elastic member that biases the valve member in a direction to increase the flow path area, and air at one end and air generated by the engine drive at the other end. an operating pressure supply device for anti-skid control, comprising: movable members each receiving a negative pressure and urging the valve member in a direction in which the flow path area is reduced against the elastic member.