JPH08244584A - Hydraulic pressure control device for antilock - Google Patents

Abstract

PURPOSE: To provide a new type liquid pressure control device for antilock using a gate valve in which the requirement in the accuracy is not so high, and the advantage in the cost is obtained, instead of a flow valve of a spool type used conventionally. CONSTITUTION: A solenoid valve 3 is opened, and the brake liquid in a wheel cylinder flows in a reservior 4, and in this case, the liquid pressure of the wheel cylinder operates to a piston 61 through the third port 71, and the piston 61 moves to the right side by this liquid pressure so as to cut off the communication between the first port 69 and the second port 70, and the brake liquid pressure in the wheel cylinder is reduced. The solenoid valve 3 is controlled by the signal from an electron control device, and liquid pressure from the master cylinder 2 is fed to the wheel cylinder 1 through a built-in orifice 61b, so as to repressurize a brake.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antilock hydraulic pressure control device, and more particularly to an antilock hydraulic pressure control device in which a single solenoid valve and a flow valve are combined. .

[0002]

2. Description of the Related Art Conventionally, as an anti-lock hydraulic pressure control device in which one solenoid valve and a flow valve are combined, the one disclosed in Japanese Patent Laid-Open No. 5-278590 is known. .

This anti-lock hydraulic pressure control device will be described with reference to FIG. 4. In this hydraulic pressure control device, the hydraulic pressure system is connected to the front wheel side wheel cylinder 51 and the rear wheel side wheel cylinder 51a. It is divided into two branch systems, and each system is provided with flow valves 50 and 50a, respectively. Each of the flow valves 50, 50a includes a cylindrical cylinder portion 54, 54a and casings 57, 57a having a plurality of ports, and spools 58, 58a slidably arranged in the cylinder. The spools 58, 58a have casings 57, 5
A hole for communicating with and blocking the port formed in 7a is formed. A known decay valve 60 is arranged between the flow valves 50 and 50a and the reservoir 59.

The spool of the flow valve 50 in the non-actuated state of the antilock control (see the flow valve on the left side in the figure) has a first port 53 → first hole 52 → upper hole 61 → second hole 55 → and a second port. The hydraulic pressure generation source and the wheel cylinder 51 of each branch system are communicated with each other through the upper port 56 of the port, and the wheel cylinder can be pressurized by depressing the brake pedal.

When the anti-lock control is started (see the flow valve on the right side in the figure), the decay valve 60 is opened, so that the brake fluid present in the portion surrounded by the lower hole 62 and the lower portion of the casing. Flows into the reservoir 59, and the hydraulic pressure difference between the ends of the spool 58a causes the spool 58a to move downward to block the communication between the first port 53a and the first hole 52a, and the wheel cylinder 5
1a and the reservoir 59 to the lower port 63 of the second port →
A pump that communicates through the third hole 64 → lower hole 62 → and the third port 65 to allow the brake fluid in the wheel cylinder 51a to flow into the reservoir 59, and to operate the brake fluid that has flowed into the reservoir simultaneously with the start of the antilock control. Thus, the brake fluid pressure in the wheel cylinder is reduced by returning to the master cylinder.

At the time of re-pressurization under antilock control, the decay valve is closed so that the orifice 66 provided at the fourth port of the flow valve 50a → the fourth hole 67 which communicates minutely with the fourth port → the upper hole 61a → the small diameter Hole 68 →
The wheel cylinder is repressurized at a substantially constant flow rate through the lower hole 62, the third hole 64, and the lower port 63 of the second port.

As described above, in the anti-lock hydraulic pressure control device, one decay valve (electromagnetic valve) and a flow valve are combined, and the brake pressure in the wheel cylinder is reduced, held, and increased by opening and closing the decay valve. It is designed to avoid the locked state of the wheels. In this example, a common pump is used for the two wheel cylinders, but a pump may be provided for each wheel cylinder.

[0008]

However, in the above-described conventional anti-lock hydraulic pressure control device, since the flow valve has the spool valve structure as described above,
High precision of parts such as diameter and surface roughness is required, resulting in high cost. Further, since it has a spool valve structure, the operation may be impaired by a minute foreign substance, and the influence on the foreign substance is sensitive. Various problems were pointed out.

Therefore, the present invention provides an anti-lock hydraulic pressure control device comprising one solenoid valve and a flow valve,
In place of the spool type flow valve that has been used in the past, a new anti-lock hydraulic pressure control device that uses a gate valve that is not very demanding in terms of accuracy and is also advantageous in terms of cost is provided. The purpose is to solve the above problems. In this device, since there is no solenoid valve in the normal brake path, a sufficient flow path can be secured and hydraulic pressure can be transmitted smoothly.

[0010]

Therefore, according to the present invention, in the anti-lock control, the brake fluid flowing from the wheel cylinder to the reservoir is pumped up by the hydraulic pump and returned to the master cylinder. In the control device, a gate valve 6 is arranged in a flow path that communicates between the master cylinder 2 and the wheel cylinder 1. The gate valve 6 is fitted in a valve seal provided on the gate valve body side so that the master cylinder 2 and the wheel are It has a piston that cuts off the communication with the cylinder 1, and the piston moves in the anti-lock control by the brake fluid pressure flowing from the wheel cylinder 1 into the reservoir 4 and fits into the valve seal so as to fit into the master cylinder 2 and the wheel cylinder 1. Supply the hydraulic pressure from the master cylinder 2 to the wheel cylinder 1 when the communication with is cut off. Has a build orifice 61b, and further connects and disconnects the wheel cylinder 1 and the reservoir 4 via a solenoid valve 3 that opens and closes in response to antilock control, and holds brake fluid pressure during antilock control, The anti-lock hydraulic pressure control device is configured to perform depressurization and re-pressurization, and is used as a means for solving the problem.

[0011]

[Action]

[In normal state] The hydraulic pressure generated in the master cylinder 2 is
The first port 69 formed in the main body 60 → the flow passage 79 formed by the valve seal and the piston → the groove 77 formed in the piston → the flow passage 78 between the backup and the outer circumference of the piston → the wheel through the second port 70 It is supplied to the cylinder and the brake operates.

[During Antilock Control] a. Reduction of wheel cylinder fluid pressure The solenoid valve 3 is opened, and the brake fluid in the wheel cylinder flows into the reservoir 4. At this time, the fluid pressure of the wheel cylinder acts on the piston 61 via the third port 71, and this fluid pressure is reduced. As a result, the piston 61 moves to the right to disconnect the communication between the first port 69 and the second port 70, and the brake fluid pressure in the wheel cylinder is reduced. b. When the brake is re-pressurized: The solenoid valve 3 is controlled by a signal from the electronic control unit, and the hydraulic pressure from the master cylinder 2 is supplied to the wheel cylinder 1 via the build orifice 61b, so that the brake is re-pressurized. become. c. Brake fluid pressure retention When the brake fluid pressure is retained, the amount of oil supplied from the master cylinder 2 to the wheel cylinder 1 via the build orifice 61b is equal to the amount of oil recirculated from the wheel cylinder 1 to the reservoir via the solenoid valve 3. Solenoid valve 3
Is controlled, and the brake fluid pressure is maintained at that state.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an anti-lock hydraulic pressure control device according to an embodiment of the present invention. The figure shows a brake piping system (a modulator for one wheel) that connects a master cylinder and one wheel cylinder in a four-channel system that controls each of the four wheels independently, and the piping of other wheel cylinders. The system has the same configuration.
Further, the electronic control device for controlling the valve is the same as the conventional one, and therefore the description of its configuration is omitted here.

In the figure, 1 is a wheel cylinder, 2 is a master cylinder, 3 is a solenoid valve (decay valve), 4 is a reservoir, 5 is a pump, 6 is a gate valve, and these are connected by a piping path as shown in the drawing. The present invention has a great feature in the construction of the gate valve 6 among these respective components. Hereinafter, the anti-lock hydraulic pressure control device will be described in detail centering on the configuration of the gate valve 6.

The gate valve 6 includes a main body 60 and the main body 6
0 has a piston 61 slidably disposed therein, and the main body 60 has a first port 69 communicating with the master cylinder and a second port 70 communicating with the wheel cylinder 1.
And a third port 7 communicating with the solenoid valve 3 and the reservoir 4.
1 and a fourth port 72 communicating with the discharge port of the pump 5 are formed, and each of these ports communicates with a cylinder 73 formed in the main body 60.

The cylinder 73 formed in the main body 60 is composed of a large diameter portion 73a and a small diameter portion 73b, and a plug 62 is attached to the end portion of the large diameter portion by a clip 63. The piston 61 is slidably supported between the portions 73b. The piston 61 has the same cross-sectional area A and cross-sectional area B in the drawing, and a build orifice 61b that connects a groove 77 (details will be described later) and the second port 70 is formed in the piston 61. There is. Further, an air chamber 75 communicating with the atmosphere is formed between the piston 61 and the plug 62,
Further, the end portion of the piston 61 on the small diameter portion side and the cylinder small diameter portion 73
A hydraulic chamber 76 communicating with the third port 71 is formed between the main body 60 on the b side.

A cup seal 64 and a valve seal 66 are provided between the cylinder large diameter portion 73a and the outer circumference of the piston 61.
And the valve seal 66 is supported by a backup 67 which functions to prevent the valve seal 66 from collapsing. In the figure, reference numeral 68 is a seal member.

In FIG. 2, the backup 67 is firmly fixed to the step portion of the cylinder 73, and the piston 6
A plurality of protrusions 66 a are formed in a circumferential shape on the surface of the valve seal 66 that faces the No. 1. A flow path 78 is provided between the backup 67 and the piston 61, and the valve seal 6
A flow passage 79 formed by a protrusion 66a is formed between the piston 61 and the piston 61, and a groove 77 is formed on the outer circumference substantially corresponding to the valve seal 66 and the backup 67 on the piston 61 side. This groove 77 has a first passage through a flow passage 79 between the piston 61 and the valve seal 66.
The groove 77 communicates with the second port 70 via the flow path 78 between the backup 67 and the piston 61, and the groove 77 further communicates with the second port 70 via the build orifice 61b. It communicates with 70.

A spring 81 for urging the piston 61 to the left in the drawing is attached between the cup seal 64 and the spring seat 80 formed on the piston 61. The space for accommodating the spring 81 is the first port. 69 and 4th port 7
It communicates with 2. The valve seal 66 is the piston 61
Is moved to the right in the figure, the inner peripheral surface 66b of the valve seal 66 comes into contact with the outer periphery 61a of the piston, and the groove 77 and the second
It has a function of cutting off the flow path 78 communicating with the port 70.

In the normal state, the piston 61 is shown in FIG.
The state shown in FIG. 2 is maintained, and the master cylinder 2 and the wheel cylinder 1 have the first port 69 formed in the main body.
-> Flow path 79-> Groove 77 formed in the piston-> Flow path 78 between the backup and the outer circumference of the piston-> Communication is performed via the second port 70. When the piston 61 moves to the right in the figure, the inner peripheral surface 66b of the valve seal 66 contacts the outer periphery 61a of the piston to cut off the flow passage 78, and as a result, the communication between the master cylinder 2 and the wheel cylinder 1 is cut off. Become. The valve seal 66 has a valve function that allows the flow of the brake fluid only from the wheel cylinder side to the master cylinder side.

Referring again to FIG. 1, the solenoid valve 3 is a normally-closed type valve that maintains a normally closed state by a mechanism capable of opening and closing the valve by a signal from an electronic control unit (not shown). Further, the reservoir 4, the pump 5, etc. are the same as those used in the conventional anti-lock hydraulic pressure control device, and the electronic control device uses the signal from the vehicle speed sensor as in the conventional case. The opening / closing of the solenoid valve 3 and the operation of the pump 5 are controlled so that control of holding, depressurizing and repressurizing the brake fluid pressure during antilock control can be executed.

This embodiment is constructed as described above,
It operates as follows. [In the normal state] In the normal state, the piston 61 is
As a result, the hydraulic pressure generated in the master cylinder 2 is maintained by the first port 6 formed in the main body 60.
9 → flow passage 79 formed by valve seal and piston → groove 77 formed in piston → flow passage 78 between backup and piston outer periphery → supplied to wheel cylinder via second port 70 to operate brake . Also,
When the brake pedal is released, the brake fluid in the wheel cylinders flows back to the master cylinder, contrary to the above, and the brakes are released. At this time, since the solenoid valve 3 is closed, the brake fluid pressure does not flow out from the solenoid valve to the reservoir side. Moreover, since the brake fluid from the master cylinder does not pass through the solenoid valve 3 and the main flow path is open, a sufficient flow path can be secured and the hydraulic pressure can be smoothly transmitted, so that the hydraulic response is good.

[During Antilock Control] When the wheels fall into the locked state during brake operation, a wheel speed sensor (not shown) detects the lock of the wheels, and the electronic control unit reduces the brake fluid pressure, holds, and repressurizes. The solenoid valve 3 is controlled to open and close according to.

A. Reduction of Wheel Cylinder Fluid Pressure The solenoid valve 3 is opened by a signal from the electronic control unit, and the brake fluid in the wheel cylinder flows into the reservoir 4.
The brake fluid that has flowed into the reservoir 4 is pumped up by the pump 5 that operates almost at the same time, and is formed in the main body through the fourth port 72 → the space between the cup seal 64 and the valve seal 66 → the master cylinder 2 through the first port 69. Bring to reflux. At this time, the hydraulic pressure of the wheel cylinder acts on the piston 61 via the third port 71, and a force for moving the piston 61 to the right is generated by this hydraulic pressure, but this force is greater than the urging force of the spring 81. Becomes larger, the piston moves to the state shown in FIG. 3, and the first port 69 and the second port 69
The communication with the port 70 is cut off. In this state, the brake fluid from the master cylinder passes through the build orifice 61b formed in the piston 61, and then the second port 7
Flow toward the wheel cylinder through 0, but the flow that reduces pressure through the open solenoid valve is the build orifice 6
Since it exceeds the amount of brake fluid supplied via 1b, the brake fluid pressure in the wheel cylinder is reduced as a whole.

B. At the time of re-pressurization of the brake At the time of re-pressurization of the brake, the solenoid valve 3 is controlled by the signal from the electronic control unit, the piston 61 is maintained in the state shown in FIG. 3, and the hydraulic pressure from the master cylinder 2 passes through the build orifice 61b. Is supplied to the wheel cylinders 1, the brake is repressurized. c. Brake fluid pressure retention When the brake fluid pressure is retained, the amount of oil supplied from the master cylinder 2 to the wheel cylinder 1 via the build orifice 61b is equal to the amount of oil recirculated from the wheel cylinder 1 to the reservoir via the solenoid valve 3. Solenoid valve 3
Is controlled by a signal from the electronic control unit, and the brake fluid pressure is maintained in the state at that time.

Next, a second embodiment according to the present invention will be described. The second embodiment is characterized in that the sectional area A of the piston 61 shown in FIG. 1 is formed larger than the sectional area B,
The other structure is the same as that of the first embodiment. In the second embodiment,
Since the sectional area A of the piston 61 is larger than the sectional area B,
When the hydraulic pressure of the master cylinder rises, a force to move the piston 61 to the right in the figure acts on the piston. When this force becomes slightly larger than the biasing force of the spring 81, the piston 61 moves to the right. The opening area of the flow passage 79 is increased, and a large amount of brake fluid from the master cylinder is supplied to the wheel cylinder via the increased flow passage 79. Therefore, the braking effect becomes sharp at the initial stage of the braking action. When the hydraulic pressure in the master cylinder further increases thereafter, the area difference causes the piston 61 to enter the state shown in FIG. 3, and in this state, the brake fluid from the master cylinder is supplied to the wheel cylinder only through the build orifice 61b. In this state, the amount of movement of the brake pad is not so large, so the amount of brake fluid supplied from the build orifice 61b is sufficient. Further, the operation during the antilock control is the same as that of the first embodiment, and therefore its explanation is omitted.

As described above, in this embodiment, the gate valve 6
The brake fluid pressure can be maintained, reduced, and repressurized during antilock control by operating the solenoid valve 3 and the solenoid valve 3. In the above embodiment, the gate valve, solenoid valve,
Although the configuration having the hydraulic port has been described, various combinations such as using the gate valve and the solenoid valve also as other wheels, or using the hydraulic port as piping that also serves as other wheels are not possible. Of course.

[0028]

As described in detail above, according to the present invention,
In an anti-lock hydraulic pressure control device including one solenoid valve and a gate valve, a structure is used in which a seal member is used to seal between the main body and the piston, instead of the spool type valve that has been conventionally used. As a result, the piston does not need to be machined to a very high degree of accuracy, and the requirements for accuracy can be reduced, so that the cost of the device can be reduced. Further, it is possible to obtain an antilock hydraulic pressure control device that is not affected by minute foreign matter. Further, by making the piston a stepped piston having a different cross-sectional area, it is possible to increase the amount of brake fluid in the initial stage of braking, and to sharpen the braking effect. And so on.

[Brief description of drawings]

FIG. 1 is a configuration explanatory diagram of a non-operating state of an antilock hydraulic pressure control device according to an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a main part of the device.

FIG. 3 is a structural explanatory diagram showing a state (during operation) during anti-lock control re-pressurization in the same apparatus.

FIG. 4 is a schematic configuration diagram of a conventional anti-lock hydraulic pressure control device.

[Explanation of symbols]

 3 Solenoid valve 6 Gate valve 60 Main body 61 Piston 61b Build orifice 62 Plug 64 Cup seal 66 Valve seal 67 Backup 69 First port 70 Second port 71 Third port 72 Fourth port

Claims (4)

[Claims] 1. A hydraulic control device for a hydraulic pressure recirculation type anti-lock system in which a brake fluid flowing from a wheel cylinder into a reservoir during antilock control is pumped up by a hydraulic pump and returned to a master cylinder. 1. A gate valve 6 is arranged in a flow path communicating with 1. The gate valve 6 has a piston which is fitted in a valve seal provided on the gate valve body side to cut off the communication between the master cylinder 2 and the wheel cylinder 1. When the anti-lock control is performed, the piston moves by the brake fluid pressure flowing from the wheel cylinder 1 into the reservoir 4 and fits into the valve seal, and when the communication between the master cylinder 2 and the wheel cylinder 1 is cut off, the master is closed. It has a build orifice 61b that can supply the hydraulic pressure from the cylinder 2 to the wheel cylinder 1. In addition, the wheel cylinder 1 and the reservoir 4 are connected and disconnected via a solenoid valve 3 that opens and closes in response to antilock control, so as to hold, reduce, and repressurize the brake fluid pressure during antilock control. A hydraulic control device for antilock, which is characterized in that it is configured. 2. The anti-lock hydraulic pressure control device according to claim 1, wherein the valve seal has a function of allowing the flow of the brake fluid only from the wheel cylinder side to the master cylinder side. 3. The anti-lock hydraulic pressure control device according to claim 1, wherein the piston is slidably held in the gate valve body 60 via seal members 64 and 68. 4. The cross-sectional area of the piston is set so that the piston can move by the hydraulic pressure from the master cylinder when the hydraulic pressure generated in the master cylinder exceeds a predetermined value. Alternatively, the anti-lock hydraulic pressure control device according to claim 2.