JPH04189661A - Liquid pressure controlling device for anti-skid brake - Google Patents

Abstract

PURPOSE:To make the size of a reaction spring of an accumulator compact by connecting a fluid pressure source of another device with a reaction chamber on the back surface of a pressure accumulating chamber of the accumulator for supplying an accumulated liquid pressure to a wheel side cylinder. CONSTITUTION:An anti-skid liquid pressure circuit 27 is connected with a main liquid pressure circuit 21 between a master cylinder 13 and wheel side cylinders 14L, 14R and 39L, 39R for front wheels and rear wheels from each outlet solenoid valve 24 between a mechanical valve 22 and a check valve 26, and this liquid pressure circuit 27 is provided with a reservor 28, a pump 29, and an accumulator 31 for accumulating a liquid pressure pressurized by the pump 29. A reaction chamber 31b of the accumulator 31 having a return spring 31a is connected with a traction control liquid pressure circuit 44 connecting a pump 36 for a liquid pressure source for a traction control means and an accumulator 37 with the main liquid pressure circuit 21 for the rear wheel, and the liquid pressure of it is used for a back pressure for the accumulator 31.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hydraulic pressure control device for an anti-skid brake, and more particularly to an accumulator that accumulates pressure when the pressure of a wheel-side cylinder is reduced when the anti-skid brake is activated.

[Conventional technology]

In a conventional anti-skid brake hydraulic pressure control device, an accumulator that accumulates pressure when pressure is reduced in a wheel-side cylinder when the anti-skid brake is activated has a configuration shown in FIG. That is, I is a master cylinder for brakes, 2 is a pump pressure cut valve, 3 is a solenoid valve for anti-skid control, 4 is a pump, and 6 is an accumulator, which takes out fluid from a wheel-side cylinder (not shown) when anti-skid is activated. The pressure is then increased by the pump 4, stored in the accumulator 6, and then supplied to the wheel-side cylinder again under the control of the solenoid valve 3. In the accumulator 6, a piston 6b is built into a casing 6a, and a reaction force is applied to the piston 6b by an anti-cushion ring 6C.

(Service bulletin No. 555 issued by Nissan Motor Co., Ltd. in May 1986, “Nissan Skyline JC-15
(See page) [Problems to be Solved by the Invention] However, the accumulator 6 is configured to obtain a reaction force only by the elasticity of the reaction spring 6C, and moreover, the accumulator 6 does not apply brake pressure to the wheel-side cylinder. Is it necessary to output a corresponding high voltage? For this reason, the reaction force must be large, so
There was a problem in that the reaction force spring 6C required a large one.

The object of the present invention is to miniaturize the anti-cushion ring of the accumulator.

[Means to solve the problem]

This invention provides a main hydraulic circuit between a brake master cylinder and a wheel-side cylinder that is actuated by future hydraulic pressure to press a friction material against a rotating body, and a reservoir that receives fluid from the wheel cylinder. The anti-skid hydraulic circuit is connected to an anti-skid hydraulic circuit comprising an accumulator that receives liquid from a reservoir using a pump, accumulates pressure, and supplies this hydraulic pressure to the wheel-side cylinder, and the anti-skid hydraulic circuit is connected to the The present invention relates to a hydraulic pressure control device for an anti-skid brake, characterized in that a force chamber is connected to a fluid pressure source of another device, such as a traction control device.

As the fluid pressure source for the other devices mentioned above, it is preferable to use the hydraulic pressure of the traction control hydraulic circuit.

[Effect]

Since fluid pressure used in a device other than the anti-skid brake device, such as a traction control device, is used as back pressure for the accumulator of the anti-skid brake hydraulic pressure control device, the spring force for the back pressure is small. Enough.

When the traction control hydraulic circuit is used, there is no need to increase the capacity of the hydraulic pressure source because the traction control system is not in use when the anti-skid brake system is in use.

〔Example〕

FIG. 1 shows an embodiment of the present invention, in which the brake pedal 11 is connected to the master cylinder 1 via a hydraulic booster 12.
A normally open mechanical valve 22 is interposed in the main hydraulic pressure circuit 21 between the master cylinder 13 and the wheel-side cylinders 14L' and 14R for the front wheels. From the mechanical valve 22 to the left and right wheel-side cylinders 14L, 14R, the main hydraulic circuit 21 is divided into two parts toward these cylinders. Further, this main hydraulic circuit 21 is provided with a bypass circuit 23 that bypasses the mechanical valve 22, and a bypass check valve 23a is disposed in this bypass circuit 23.

Wheel side cylinders 14L, 1 of the main hydraulic pressure circuit 21
There is an outlet solenoid valve 2 near 4R.
4 are disposed, and inlet solenoid valves 25 are disposed on the side of the mechanical valve 22 from these valves 24, and inlet solenoid valves 25 are disposed, respectively, between these valves 25 and the back pressure input section of the mechanical valve 22. A check valve 26 is provided.

An anti-skid hydraulic circuit 27 is connected to the main hydraulic circuit 21 from both outlet solenoid valves 24 to between the mechanical valve 22 and an accumulator check valve 26 in a detour manner. This hydraulic circuit 2
7 includes a reservoir 28 that reduces and stores the fluid pressure in the wheel side cylinders 14L and 14R, a pump 29 that extracts and pressurizes the fluid, and an accumulator 31 that accumulates the fluid pressure pressurized by the pump 29. Check valves 32, 33 are arranged before and after the pump 29.

In the figure, numeral 34 is a trifice detour circuit, and a check valve 34a is interposed therebetween. 35 is a small diameter orifice.

The same circuit as the circuit between the master cylinder 13 and the wheel-side cylinders 14L and 14R for the front wheels described above is the same as the circuit between the master cylinder 13 and the wheel-side cylinders 39L for the rear wheels.
, 39R, but since this circuit is shown vertically symmetrically in Fig. 1, each part of the rear wheel circuit is given the same reference numeral as each part of the front wheel circuit. The detailed explanation will be omitted.

The accumulator 31 includes a small return spring 31a, and its reaction force chamber 31b is a traction control device that connects the pump 36 and accumulator 37, which are the hydraulic pressure source of the traction control device, to the main hydraulic pressure circuit 21 for the rear wheels. It is connected to the hydraulic pressure circuit 44, and its hydraulic pressure is used as the back pressure of the accumulator 31.

The pump 36 and the accumulator 37 pressurize and accumulate the brake fluid in the reservoir tank 38 of the brake master cylinder 13, and supply this fluid pressure to the wheel-side cylinders 39L and 39R for the rear wheels, which are the driving wheels. For this purpose, the traction control hydraulic circuit 44
Mechanical valve 41 and normally closed solenoid valve 4
2, and a normally open solenoid valve 43 is disposed in the main hydraulic pressure circuit 21 for the rear wheels.

Next, the operation of this embodiment will be explained. Here, the circuit for the front wheels will be mainly explained, or the circuit for the rear wheels will operate in the same manner.

First, when the anti-skid brake is not activated, the hydraulic pressure generated in the master cylinder 13 when the brake pedal II is depressed is as shown by the solid arrow in the main hydraulic circuit 2.
It passes through the mechanical valve 22 and inlet solenoid valve 25 in the front wheel cylinder 14.
It is supplied to L and 14R, where braking force is obtained. Here, since the hydraulic pressure bypasses the small diameter orifice 35, a smooth braking force can be obtained.

When the brake pedal 11 is released, the front wheel side cylinder 14L, as shown by the chain arrow,
The hydraulic pressure of 14R returns to the reservoir tank 38 via a bypass circuit 23 equipped with a bypass check valve 23a.

Further, when the anti-skid brake is activated and the hydraulic pressure in the wheel-side cylinders 14L and 14R is maintained, the outlet solenoid valve 24 and the inlet solenoid valve 25 are closed to contain the hydraulic pressure. At this time, the brake pedal 11 is in a depressed state, and hydraulic pressure is applied to the bypass circuit 23 from the master cylinder 13 to the check valve 23a.
The sealed hydraulic pressure does not return to the master cylinder 13 from the check valve 23a. When the confined hydraulic pressure is reduced, the outlet solenoid valve 24 is opened to release the hydraulic pressure in the cylinders 14L, 14R to the reservoir 28 of the anti-skid hydraulic circuit 27, where it is stored.

The liquid in the reservoir 28 is pressurized by the pump 29 and stored in the accumulator 31, and when liquid pressure is generated there, it acts as back pressure on the mechanical valve 22, causing the valve 22 to close.

The hydraulic pressure accumulated in the accumulator 31 receives a back pressure of the hydraulic pressure from the traction control hydraulic pressure circuit 44 and the small return pressure generated by the small return spring 31a, thereby obtaining a reaction force. Here, when it is necessary to increase the pressure in the wheel-side cylinders 14L, 14R for the front wheels, the pressure in the wheel-side cylinders 14L, 14R for the front wheels is increased through the opened inlet solenoid valve 25.

cormorant. Here, too, since the play rate pedal 11 is in the depressed state, the hydraulic pressure accumulated in the accumulator 31 does not return from the bypass circuit 23 to the master cylinder 13 side. At this time, the pulsation of the hydraulic pressure generated by the pump 29 is absorbed by the accumulator 31, so that the pulsation transmitted downstream from the accumulator 31 is reduced.

In particular, when the hydraulic pressure is circulated through the anti-skid hydraulic circuit 27 (dotted arrow), since the mechanical valve 22 is closed, the pump 29 is supplied to the brake pedal II side through the small diameter orifice 35. The pulsation is only slightly transmitted as information, and the pulsation that causes discomfort is not transmitted.

Note that the hydraulic pressure of the traction control hydraulic pressure circuit 44 is consumed for traction control when the vehicle starts, so it is not originally used when the anti-skid brake is activated by depressing the brake pedal 11. In this way, since the traction control and anti-skid brakes do not operate at the same time, there will be no problem if the hydraulic pressure of the traction control hydraulic pressure circuit 44 is used for the reaction force of the accumulator 310 for the anti-skid brake. does not occur.

In this embodiment, a hydraulic pressure source for traction control is used as the back pressure for the anti-skid brake accumulator 31, but instead of this, a hydraulic pressure source for other devices, such as a power steering device or a vehicle A hydraulic pressure source such as a height adjustment device can be used, or a pneumatic pressure source such as a pneumatic vehicle height adjustment device can be used instead of the hydraulic pressure. In these cases, the pressure of the fluid pressure source used as back pressure can be set to a suitable reaction force by adjusting the back pressure receiving area of the accumulator 31.

〔Effect of the invention〕

As explained above, in this invention, since the fluid pressure of another device is used as the back pressure of the anti-skid brake accumulator, it is possible to miniaturize the return spring built in the accumulator as much as possible. This has the effect of making it possible to make the anti-skid brake device smaller and lighter, while also ensuring a sufficient output of the accumulator.

Furthermore, since the traction control and anti-skid brake do not operate at the same time, if the hydraulic pressure source of the traction control device is used as the other fluid pressure device, it is possible to obtain the above effect without increasing the size of the device. There is also the effect that it can be done.

[Brief explanation of the drawing]

FIG. 1 is a hydraulic circuit diagram showing an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional anti-skid brake accumulator. 1] Brake pedal, 13 Master cylinder, 14L, 14R, 39L, 39R Wheel side cylinder, 21 Main hydraulic circuit, 22 Mechanical valve, 23 Bypass Circuit, 24... Outlet solenoid valve, 25... Inlet solenoid valve, 27... Hydraulic pressure circuit for anti-skid brake, 28... Reservoir tank, 29... Pump, 31... Anti Skid brake accumulator, 31a... return spring, 31b...
Back pressure chamber, 36... Traction control pump, 37... Traction control accumulator, 44... Traction control hydraulic circuit. Patent applicant Nissan Motor Co., Ltd. Aggunisia Co., Ltd.

Claims (2)

[Claims] (1) A reservoir that receives fluid from the wheel cylinder in the main hydraulic circuit between the brake master cylinder and the wheel-side cylinder that is actuated by future hydraulic pressure to press the friction material against the rotating body, and this reservoir. In the anti-skid brake hydraulic pressure control device, the anti-skid brake hydraulic pressure circuit is connected to an anti-skid hydraulic pressure circuit comprising an accumulator that receives and accumulates a liquid by a pump and supplies this hydraulic pressure to the wheel-side cylinder. A hydraulic pressure control device for an anti-skid brake, characterized in that a fluid pressure source of another device is connected to a reaction force chamber on the rear side of the chamber. (2) The anti-skid brake hydraulic pressure control device according to claim 1, wherein the fluid pressure source of the other device is the hydraulic pressure of a traction control hydraulic circuit.