JPS62139748A - Antiskid control device - Google Patents

Abstract

PURPOSE:To make it possible to effect highly responsive brake operation with a simple structure, by fitting two pistons which cooperate with each other, in a body having stepped cylinders so that valve sections formed respectively in both pistons carry out antiskid control operation. CONSTITUTION:In an antiskid control valve device 1 disposed in brake hydraulic pressure pipelines 2, 3 connecting between a master cylinder M/C and each wheel cylinder W/C, stepped cylinders 4-7 having diameters which increase successively from one end side, and a cylinder 8 having a diameter intermediate between the diameters of the cylinders 6, 7 are formed in a body which incorporates a first piston 9 for reducing hydraulic brake pressure and a second piston 10 for blocking the communication between the pipe lines 2, 3. Further, a valve element 9b which may be seated on a seat 10a in the second piston 10 is formed as a first valve section in one end section of the first piston 9, and a valve element 10b which is adapted to be seated on a valve seat 1a in the body is formed as a second valve section in the second piston 10.

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 wheel lock that may occur during braking.

[Background of the invention]

Conventionally, various anti-skid control devices have been provided to release wheel lock during vehicle braking. For example, such a method is such that a tm valve device and a pressure reducing device connected thereto are connected in the middle of a normal brake hydraulic pressure transmission pipe, and the solenoid valve device is actuated by an anti-skid control signal. In anti-skid control devices, there is usually a solenoid valve in the middle of the brake system piping, so it is possible that the flow path is constricted.

[Purpose of the invention]

In view of this problem, the present invention has been made with the object of providing a device in which the failure mechanism of anti-skid control in the middle of the piping of a normal brake system is reduced as much as possible.

[Summary of the invention]

The anti-skid control device according to the present invention, which has been designed for this purpose, is normally biased and locked in the initial position by the hydraulic action from the first oil chamber communicating with the pressure accumulator. When hydraulic pressure is applied from the second oil chamber facing the first oil chamber, the first piston moves in the direction of increasing the chamber volume of the reservoir oil chamber, the end of which faces the first piston, and the movement of the first piston Therefore, an anti-skid jl [I action solenoid valve device is used to supply and discharge hydraulic pressure from the second oil chamber button pressure accumulator, and normally it is biased to a position where it engages with the first piston by the spring force of a bold spring. a second piston that is locked and whose one end faces the second oil chamber and is moved in a direction away from the first piston against the spring force of the hold spring when hydraulic pressure is applied from the second oil chamber; and a circuit is closed by engagement of the first piston and the second piston,
and a first valve part that is opened by the relative movement of the first piston and the second piston in a direction of separation, and which communicates the pressure oil in the brake device with the reservoir chamber by the core opening; A second valve part comprising a normally open valve part which is closed by the movement of the second piston in the separation direction, and which shuts off a brake hydraulic pressure transmission circuit from the master cylinder to the brake device by the closing. Niruru.

[Example M of the invention]

The present invention will be described below based on embodiments shown in the drawings.

In the figure, reference numeral 1 indicates an anti-skid control valve device interposed in the middle of a brake hydraulic pressure transmission pipe 2.3 connecting between the master cylinder sVL/C of the vehicle and the wheel cylinder W'C of the brake device. A body (not shown) having stepped cylinders 4, 5, and 6.7 that are successively concentrically provided with larger diameters from the side, and a cylinder 8 that is further outside cylinder 7 and has an intermediate diameter between cylinders 6.7 and 6.7. A first piston 9 for reducing brake oil pressure and a second piston 10 for cutting off communication between the brake oil pressure transmission pipes 2 and 3 are housed inside.

The first piston 9 includes the cylinders 6, 7. 8, the end of the cylinder 8 facing the AA (first oil chamber) communicating with the pressure accumulator, and the stepped shoulder of the cylinder 6 facing the 81J misaki oil chamber BB (first oil chamber). The stepped end face facing K and slidingly fitted to the cylinder 7 faces the reservoir oil chamber CC and the release oil chamber DD, and is normally stopped in the direction of the oil chamber BB by the hydraulic action from the oil chamber AA. It is biased and locked in position.

Note that the first piston 9 is arranged in the oil chamber AA in the oil chamber BB.
A fail-safe spring 11 that presses in the direction is tensioned.

Further, the second piston 1o is slidably fitted over the cylinder 4°5, and the end of the cylinder 511111 is cylindrical and slides oil-tightly onto the small diameter shaft end 9a of the first piston 9. The two ends face the oil chamber BB. Further, this second piston 10 is pressed in the direction of the oil chamber BB by a hold spring 12, and is engaged with a valve portion 9b formed at the tip of the small diameter shaft end portion 9a of the first piston 9 inside the cylindrical end portion. The foil cylinder W/C can communicate with the reservoir oil chamber CC through the first valve portion constituted by the valve seat 10a1 and the valve body 9b. In addition lo
c is a flow path within the first piston 9 for providing this communication.

Furthermore, the second piston 1o has a groove formed in the valve body 10bK between a valve seat 1a formed in the body and a normally open second valve portion that is opened and closed. The brake hydraulic pressure transmission pipes 2 and 3 are cut off by this.

The pressure accumulator 13 uses a pump 14 to pump up pressure oil from a reservoir tank 15 to maintain a predetermined oil pressure state at all times, and always transmits this oil pressure to an oil chamber AA, which is a first oil chamber, to keep the first piston 9 in the state shown in the figure. It is also connected to an oil chamber BH, which is a second oil chamber, through a pressure reducing valve 16, which is a normally closed electromagnetic valve for anti-skid pressure reduction. Further, this oil chamber BB is connected to the reservoir tank 15 via a pressure valve 17 which is a normally open electromagnetic valve for applying anti-skid pressure.

Note that the pressure reducing valve 16 and the pressurizing valve 17 are operated and controlled by an electronic control device for anti-skid control (not shown), and the specific control thereof can be carried out by the above-mentioned methods depending on the wheel rotation state. It's fine if it's given to you.

Next, we will discuss its operation.

The device of this example is normally in the state shown in the figure (during non-anti-skid control), where the first piston 9 is locked at an even-odd initial position on the oil chamber BB side, and the second piston 10 is held by a hold spring 12. Valve seat 10 against core first piston 9
The initial position where a is in contact with the valve body 9b is arranged in even and odd positions.

Therefore, when the first valve portion is in a closed state, the reservoir oil chamber CC is cut off from the wheel cylinder W/C of the brake device. Further, the second valve portion consisting of the valve seat 1a and the valve body 10b is in the normally open state, and the brake hydraulic pressure transmission pipes 2, 3
are communicated.

During anti-skid control, when pressure oil from the pressure accumulator 13 is transmitted to the oil chamber BB by opening the pressure reducing valve 16 and closing the pressurizing valve 17, the second piston 10 first moves upward in the figure against the hold spring 12. and close the second valve part. Therefore, communication between the brake device and the master cylinder is cut off.

Next, the first piston 9 is moved toward the oil chamber AA by the hydraulic action of the oil chamber BB, and the internal volume of the reservoir oil chamber CC is increased. At this time, since the first piston 9 and the second piston 10 are moving relative to each other in the direction of separation, the first piston 9 and the second piston 10
The valve portion is opened, so that the pressure oil in the wheel cylinder W/C of the brake device flows into the reservoir oil chamber CC, and the brake oil pressure is reduced.

The brake hydraulic pressure is given by releasing the pressure oil in the oil chamber BB by opening the pressure valve 17 and closing the pressure reducing valve 16, and ultimately moves the second piston 10 toward its initial position. As a result, the first valve portion is returned to its open state and returns to its normal state.

In addition, in this example, even if the hydraulic pressure of the pressure accumulator fails, the first piston 9 is maintained at its initial position by the spring force of the safe spring 11, so that normally the brake system will not malfunction. [Effects of the Invention] According to the present invention, since the flow path of the normal brake system is independent of the anti-skid control device except for passing through the first valve part, the constriction shape of the flow path is It is said that there is almost no need to consider Genda's brake system, and a highly responsive normal brake operation can be obtained, and amplifier skid control operation can be applied without causing the new kick pack to the master cylinder side. Effects can be obtained.

[Brief explanation of drawings]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawings are diagrams showing a general configuration example of an anti-skid control device according to the present invention. 1... Anti-skid control valve device 2.3... Brake hydraulic pressure transmission pipe 4, 5.6.7.8... Cylinder 9... First piston 10... Second piston 11
...7 Ail-safe spring 12...Hold spring 13...Pressure accumulator 14...Pump 15...
Reservoir tank 16...pressure reducing valve 17...pressurizing valve.

Claims (1)

[Claims] Normally, it is biased and locked in the initial position by the hydraulic action from the first oil chamber communicating with the pressure accumulator, and when the hydraulic pressure is applied from the second oil chamber opposite to this first oil chamber, its end part A first piston that causes the movement of the facing reservoir oil chamber in the direction of increasing the chamber volume, and an electromagnetic electromagnetic device for anti-skid control that supplies and discharges hydraulic pressure from the pressure accumulator to the second oil chamber for the movement of the first piston. The valve device is normally biased and locked in a position where it engages with the first piston by the spring force of a hold spring, and one end faces the second oil chamber, so that hydraulic action from the second oil chamber is applied. The second piston is moved away from the first piston against the spring force of the hold spring.
a piston, and a valve portion which is closed by the engagement of the first piston and the second piston and opened by the relative movement of the first piston and the second piston in a direction of separation; a first valve part that communicates pressurized oil with the reservoir chamber, and a normally open valve part that is closed by the movement of the second piston in the separating direction, and the closed circuit allows the flow from the master cylinder to the brake device. An anti-skid control device comprising: a second valve portion that shuts off a brake hydraulic pressure transmission circuit.