JPS61184159A - Antiskid control unit of vehicle - Google Patents

Abstract

PURPOSE:To securely prevent the generation of kick back by providing an always-open type gate valve and an always-open type hold valve which is closed by an antiskid pressure reducing signal, in the main passage of a brake hydraulic pressure transmitting main passage and making said gate valve close said main passage by means of pressure difference. CONSTITUTION:A circuit which is led to a wheel cylinder W/C through the closing valve chamber 2a of a gate valve 2 and a hold valve 3, is provided in a main passage which connects a master cylinder M/C to the wheel cylinder W/C. The hold valve 3 is an always-open type valve which is closed by an antiskid pressure reducing signal from an antiskid control circuit. A bypass 4 is connected to the main passage1c on the lower course of the hold valve 3, and an always-closed type pressure reducing valve 5, reservoir 6, a pump 7, an accumulator 8 and a return valve 9 are provided in order in this bypass 4. And, said gate valve 2 is of always-closed type which is closed by a pressure difference Pa > Pi between oil pressure Pi which is reduced by the pressure reducing valve 5, and oil pressure Pa in the accumulator 8.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an anti-skid control device for suitably eliminating the occurrence of wheel locking during braking of a vehicle.

[Background of the invention]

Recently, various types of anti-skid control technologies have been proposed to improve safety during vehicle braking.
A typical example of such a thing is, for example, when the brake hydraulic pressure transmission path (hereinafter referred to as the main path) connecting between the master cylinder (hydraulic pressure generating device t) and the brake device is normally open and the brake hydraulic pressure decreases. A normally open shutoff valve that closes when necessary is installed, and a bypass connection path (hereinafter referred to as the bypass path) is provided to this main path, and the brake equipment side of this bypass path and the main path are connected. The output system is separated by a normally closed pressure reducing valve, and the brake pressure oil flowing into the bypass passage through the normally closed pressure reducing valve, which is opened when it is necessary to lower the brake oil pressure, is transferred indoors under pressure. The hydraulic oil is stored in a reservoir mechanism that stores oil while decreasing the oil pressure by increasing the volume, and this reservoir in the mechanism is pumped into the main path by a pressure oil return mechanism including a pump, and the shutoff valve (normally An electronic control circuit has been proposed in which the opening/closing operation of a pressure reducing valve (open type) and a pressure reducing valve (normally closed type) is performed by an electronic control circuit that detects wheel lock during vehicle braking.

By the way, in anti-skid control as typified by the above example, the main path for transmitting brake hydraulic pressure is divided into multiple input system and output system paths by a normally open shutoff valve, and anti-skid control is During control, the pressure oil in the brake device (i.e., the pressure oil in the output path) is pumped up to the master cylinder side (i.e., the input path side), so the oil pressure fluctuation in the master cylinder increases. However, there is a problem in that the brake pedal that is linked to the master cylinder is given a so-called kickback movement.

For this reason, measures have been taken in the past to avoid the kickback phenomenon. For example, as shown in Japanese Patent Laid-Open No. 55-19700, pressurized oil is provided only in the downstream direction further upstream of the input path for pumping brake oil pressure. It has also been proposed to install a reverse valve to allow the flow of water.

However, in such a system, it goes without saying that the brake system (hereinafter referred to as W/C as the case may be) side is transferred to the master cylinder (hereinafter as the case may be referred to as J M/C) side when the brake is released. A separate path for returning the hydraulic pressure is required, and
This hydraulic return path is in the opposite direction M/C-+W/
It is essential to reliably block the flow of pressure oil in C and to prevent any residual balls from remaining inside the brake device W/C in order to prevent dragging when the brake is released. The difficulty is great.

0 [Object of the Invention] The present invention solves the conventional problems and reliably prevents the occurrence of kickback, and also provides an anti-lock brake system with a gate valve that ensures the return of brake hydraulic pressure to the master cylinder when the brake is released. This was made for the purpose of providing a skid control device.

Another object of the present invention is to provide an anti-skid valve equipped with a gate valve that allows pressure oil to flow in the main path during normal braking and to ensure that the main path is closed during anti-skid control. The control device is provided.

[Summary of the invention]

The gist of the anti-skid control device of the present invention, which has been made to achieve the above object, is that a normally open gate valve, a normally open gate valve, Next, a normally open hold valve that is closed by the anti-skid pressure reduction signal is provided, and a normally closed pressure reducing valve that is opened by the anti-skid signal is inserted into the main path on the downstream side of the brake device of the hold valve. A bypass path is provided for pumping up the pressure oil in the path to the accumulator and returning the pressure oil from the accumulator between the gate valve and the hold valve in the main path, and further, the gate valve is configured to pump the reduced brake oil pressure Pi and the oil pressure in the accumulator. The main path is closed due to the differential pressure Pa>Pi.

[Embodiments of the invention]

The present invention will be explained below based on the drawings.

In the figure, 1a to IC are outgoing paths (main paths) for transmitting brake hydraulic pressure, and are connected so as to communicate between a master cylinder M/C (not shown) and a wheel cylinder W/C of a brake device, and gates are provided on the way. It passes through the opening/closing valve chamber 2a of the valve 2, passes through the hold valve 3, and reaches the foil cylinder W/C.

Ru. The hold valve 3 is a normally open valve that is electromagnetically closed, and the closing is activated by an antiskid pressure reduction signal that is output by an antiskid control circuit (not shown) to release wheel locking when the vehicle is braking. It's like that. In addition, as will be described later, the gate valve 2 is normally operated in the open/close valve chamber 2.
A is open, allowing communication between the main paths 1a and 1b.

4 is a bypass path connected to the main path IC downstream of the hold valve 3, and includes a normally closed pressure reducing valve 5, a reservoir 6, a pump 7, and an accumulator 8, which are electromagnetically opened by an anti-skid pressure reducing signal. , a return valve 9 are sequentially provided, and when the pressure reducing valve 5 is opened, the brake hydraulic pressure (hydraulic pressure in the main path IC and the wheel cylinder W/C) is reduced by causing pressure oil to flow into the reservoir 6,
This pressure oil is pumped up to an accumulator 8 by a pump 7 and then returned from a return valve 9 to the main path 1b between the gate valve and the hold valve.

Next, the structure of the gate valve 2 will be explained. The gate valve 2 of this example has a stepped cylinder 1 in a cylinder body (not shown).
0.11, the stepped piston 12 is slid together, and its small diameter end faces the on-off valve chamber 2a, and is biased to a predetermined position on the large diameter end side by the set spring 13 engaged with the small diameter end. K is set so that it can be stopped in a state. At the small diameter end of the stepped piston 12, there is a valve element @1 which closes the opening/closing valve chamber 2a by moving against the spring force of the set spring 13 of the stepped piston 12 in cooperation with the valve seat 14.
5 is provided to cut off communication between the main path 1a and IbO when the circuit is closed.

This movement of the stepped piston 12 against the spring force of the set spring 13 is carried out when the hydraulic pressure of the pressure oil from the accumulator acts on the large diameter end. The stepped shoulder oil chamber 16 is always in communication with the main path 1b. The return valve 9 is built into the large diameter portion of the stepped piston 12, and the flow of pressure oil from the accumulator 8 is controlled by the downstream main path 1b of the opening/closing valve chamber 2a.
It is designed to allow only

Reference numeral 18 is a check valve that allows pressure oil to return from the wheel cylinder W/C to the master cylinder M/C, further ensuring that the pressure oil returns when the brake is released.

Regarding the operation of the anti-skid control device with the above configuration, during normal braking, the master cylinder M/
The oil pressure from C is the main path 1a.

Ib and 1c are transmitted to the foil cylinder W/C in this order,
Generates braking force. At this time, no hydraulic pressure that would close the on-off valve chamber 2a acts on the stepped piston 12 of the gate valve 2, so there is no problem of restricting the flow of pressure oil in that part, and there is no delay in brake operation. does not occur.

Next, when a wheel lock occurs during vehicle braking and anti-skid control is performed, first the hold valve 3 is closed and the pressure reducing valve 5 is opened in response to a pressure reduction signal from an anti-skid control circuit (not shown). As a result, the main path 1a,
Direct communication between Ib and Ib is cut off, and the pressure oil in the main path Ib flows into the reservoir 6, and the brake oil pressure is reduced by pressure reduction. Therefore, the braking force is reduced, and the wheel lock is released. The pressure oil that has flowed into the reservoir 6 is pumped up by the pump 7 to the accumulator 8, and when its hydraulic action acts on the large diameter end of the stepped piston 12,
The stepped piston 12 moves to close the on-off valve chamber 2a, and thereafter completely shuts off communication between the upstream (master cylinder side) and downstream (brake device side) of the gate valve 2,
This will not cause a kick-hack to the brake pedal. The brake oil pressure is repressurized by opening and closing the hold valve 3 in response to a repressurization signal from an anti-skid control circuit (not shown).

You can give it by letting it flow.

The anti-skid control circuit for providing the above-mentioned anti-skid signal may be configured by known means.

According to the above configuration, the gate valve 2 causes the stepped piston 12 to move only after the pressure oil is pumped up to the accumulator after the brake oil pressure is reduced, and thereby the main path 1a.

Although the communication between Ib and Ib is cut off, in other cases, the stepped piston 12 does not move, and the system has the effect of ensuring smooth communication between the main paths la, lb, and lc. Also, during anti-skid control, the master cylinder and brake device are pressure-blocked by a gate valve, so there is no kickback to the brake pedal, and the return of pressure oil when the brake is released is also guaranteed by opening the gate valve. There is an effect.

〔Effect of the invention〕

According to the present invention, it is possible to ensure proper operation of anti-skid control when braking a vehicle, prevent kick-pack to the pedal, and ensure that pressure oil returns when the brake is released. You get flow assurance and its usefulness is a dog.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a vehicle amplifier skid control device according to the present invention. 1a~IC...Main path 2...Gate valve 2a.
...Opening/closing valve chamber 3...Hold valve 4...Bypass path 5...Pressure reducing valve 6...Reservoir
7... Pump 8... Accumulator 9.
...Return valve 10.11...Stepped cylinder 12...Stepped piston 13...Set swivel 14...Valve seat 15...Valve body portion 16...
・Oil chamber 17...Flow path.

Claims (1)

[Claims] In the main path for transmitting brake hydraulic pressure from the master cylinder to the brake device, a normally open gate valve is installed from the upstream master cylinder side, and then a normally open hold valve that is closed by an anti-skid pressure reduction signal is provided. Pressure oil in the main path is pumped up to an accumulator through a normally closed pressure reducing valve that is opened by an anti-skid signal in the main path on the downstream brake device side of the main path, and from this accumulator to the main path between the gate valve and the hold valve. A bypass passage for returning pressure oil is provided in the vehicle, and the gate valve has a structure in which the main passage is closed by a pressure difference Pa>Pi between the reduced brake oil pressure Pi and the oil pressure Pa in the accumulator. Anti-skid control device.