JPH0717379A - Antiskid controller - Google Patents

Abstract

PURPOSE:To dispense with a special valve mechanism and simplify device and reduce the dimension and weight by allowing a master cylinder and a wheel cylinder to communicate each other, even if the device fon generating a power pressure fails in the antiskid control. CONSTITUTION:An antiskid controller is constitued so that the first control valve 41 allows a master cylinder and a wheel cylinder to communicate each other in the ordinary case, and cuts off the communication in the antiskikd control, and the second control valve 42 cuts off the communication between the wheel cylinder and a decompression chamber in the ordinary case and permits communication in the antiskid control. The first control valve 40 is constituted of a fail-safe piston 20 which is arranged in a slidable manner in the body of a gate valve and shifts in the antiskikd, and the first valve bodies 44 and 45 which close a flow passage by the drop into a groove part 28 formed on the upper periphey, and the second control valve 42 is formed from a fail-safe piston and the second valve body 23 which is arranged in the flow passage formed inside and opens the flow passage by the shift of the fail-safe piston.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-skid control device capable of optimally controlling a wheel braking force in order to prevent skid of a wheel during braking of a vehicle. Specifically, the present invention relates to an anti-skid control device in which the responsiveness of the control system is good and the brake operation can be reliably realized even when the power fails.

[0002]

2. Description of the Related Art In recent years, an anti-skid control device has been actively developed for the purpose of improving steering stability during braking and facilitating a driver's driving operation. Japanese Patent Publication Sho 59
Those described in Japanese Patent Publication No.-2655 are known.

The anti-skid control device described in the above publication discloses a brake master cylinder, a defect detection device for detecting a defect in a front wheel brake system that performs a braking action by the braking pressure from the master cylinder, and a braking pressure from the master cylinder. One or more rear wheel brakes that perform a braking action by an actuator, an actuator that is disposed between the master cylinder and the rear wheel brake, and that reduces the braking pressure of the rear wheels in accordance with the skid skid state of the wheel being braked; Control means for issuing a pressure reduction and command signal to the actuator, a pressure source capable of generating a power pressure of the actuator, a constant pressure is supplied to the actuator during non-braking, and the power pressure is proportional to the braking pressure during braking. An adjusting device for adjusting the adjusted pressure to the actuator and supplying the adjusted pressure to the actuator; The decompression chamber provided in the user is connected to the rear wheel brakes, and the master cylinder is disconnected from the rear wheel brakes. When the adjusted pressure disappears, the decompression chamber is disconnected from the rear wheel brakes. A bypass valve that connects the master cylinder and the rear wheel brakes, and an open / close valve that opens and closes the communication between the master cylinder and the decompression chamber provided in the actuator when the braking pressure is less than or equal to the braking pressure set by the action of the adjusting pressure. To increase the outlet braking pressure of the actuator at the same rate of increase as the inlet braking pressure, and when the inlet braking pressure of the actuator becomes equal to or higher than the set braking pressure, the on-off valve is opened and closed to open the outlet of the actuator. A means for reducing the rate of increase of the braking pressure to be smaller than the rate of increase of the inlet braking pressure, and the adjustment pressure disappeared by a switching valve that works in conjunction with the defect detection device. It is characterized in that it comprises means for.

The anti-skid control device adds a proportioning valve function to the conventional anti-skid control device, and when the front brake is lost, the proportioning valve function of the actuator is eliminated and the master cylinder pressure is directly supplied to the rear wheel brake. Therefore, the braking distance when the front brake is lost can be made much shorter than that of the actuator having the proportioning valve function of the actuator even when the front brake is lost.

[0005]

However, in the anti-skid control device having the above-described structure, it is necessary to constantly supply a constant pressure to the actuator even during non-braking. Therefore, the hydraulic circuit is constantly operated during the operation of the device. Also, since the hydraulic pressure is acting on the seal part in the circuit, it is necessary to use a pressure resistant specification for the seal part and the circuit itself. Further, since the high hydraulic pressure acts on the seal portion of the hydraulic circuit for a long time, the deterioration of the seal portion is accelerated due to this. Further, in this device, it is necessary to provide a fail-safe valve mechanism for disconnecting the communication between the brake circuit and the actuator when the device that generates the power pressure fails, so that the device becomes complicated and expensive. However, there are problems such as difficulty in miniaturization.

In view of the above, according to the present invention, hydraulic pressure does not act in the anti-skid control hydraulic pipe during non-braking and during normal brake operation, so that the hydraulic pipe and the seal portion in the circuit are protected. It is intended to propose an anti-skid control device that has improved durability and high responsiveness during control and is highly reliable. Further, the present invention eliminates the need for a special valve mechanism for failsafe by providing a mechanism in which the master cylinder and the wheel cylinder communicate with each other immediately even if the device that generates the power pressure during anti-skid control fails. It is intended to simplify the structure of the device, reduce the size and weight of the device, and improve the durability of the device. Further, according to the present invention, the valve portion for switching between the normal hydraulic circuit and the hydraulic circuit for control is configured as a ball valve of a thrust valve seat that is easy to process, and a cutoff valve is provided in the valve housing to reduce the size of the device. The purpose is to achieve

[0007]

Therefore, according to the present invention, the first control valve 40 is provided in the oil passage connecting the master cylinder M / C and the wheel cylinder W / C and the wheel cylinder W / C and the pressure reducing valve are provided. A second control valve 50 is provided in an oil passage connecting to the chamber 36, and the first control valve 40 normally connects the master cylinder M / C and the wheel cylinder W / C to each other, and the master cylinder M / C is connected during the anti-skid control. C and wheel cylinder
The second control valve 50 normally disconnects the wheel cylinder W / C from the decompression chamber 36 and disconnects the wheel cylinder W / C from the anti-skid control.
In the anti-skid control device having a configuration in which C and the decompression chamber 36 are communicated with each other, the first control valve 40 is slidably arranged in the main body of the gate valve 30, and is controlled by a hydraulic pressure source during anti-skid. And a first valve body 44, 45 that closes the flow path by falling into a groove 28 formed on the outer periphery of the fail-safe piston.
Further, the second control valve 50 includes the fail-safe piston and a second valve body 23 that is disposed in the flow dew formed inside the fail-safe piston and that opens the flow path by the movement of the fail-safe piston. And these are used as means for solving the problems.

[0008]

[Action]

[During normal brake operation] When hydraulic pressure is generated in the master cylinder M / C by operating the brake pedal B / P, the hydraulic pressure from the master cylinder M / C is changed from the inlet passage 15 to the first control valve 40 →
Wheel cylinder W / C through groove 28 → outlet passage 16
Is supplied to. When the brake pedal B / P is released, the hydraulic pressure in the wheel cylinder W / C is changed from the outlet passage 16 to the groove 28 to the first.
Master cylinder M / C through control valve 40 → inlet passage 15
Is released to the brake and the brake is released.

[During Anti-Skid Control] When the wheel is skid during brake operation, the power supply valve 4 is turned on by a signal from an electronic control unit (not shown).
Switch to position. As a result, the accumulator pressure acts on the pressure acting passage 14 formed in the gate valve housing 13 to move the fail-safe piston 20 to the left in the figure against the biasing force of the set spring 25. Then, the ball 45 of the cutoff valve 40 falls into the groove 28 to close the flow path, and the valve rod 26 causes the ball 2 to move.
3 is pushed up to open the second control valve 50, and the brake fluid in the wheel cylinder W / C is discharged from the outlet passage 16 → valve chamber 32 → second
The control valve 50 → flow path 21 → passage 38 → pressure reducing chamber 36 flows in, and the brake of the wheel is released while moving the control piston 11 to the left against the urging force of the control spring 12.

In this state, when the hold valve 5 and the decay valve 6 are in the C position and the F position, a high hydraulic pressure from the accumulator 3 flows into the oil chamber 37 from the pressure adjusting passage 17, and this hydraulic pressure is controlled by the control piston 11. Is moved to the right in the figure and the brake fluid flowing into the decompression chamber 36 is discharged to the second position.
It can be supplied to the wheel cylinder W / C via the control valve 50 to apply a brake to the wheels.

[During Power Pressure Failure] Further, if the device that generates power pressure during anti-skid control fails, the high pressure from the accumulator 3 does not act on the fail-safe piston 20, so the fail-safe piston 20 is set spring. 1, the second control valve 50 is closed, the first control valve 40 is opened, the outlet passage 16 and the inlet passage 15 are communicated with each other, and the master cylinder M / Operate the brake with hydraulic pressure from C.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a hydraulic piping diagram of an anti-skid control device according to an embodiment of the present invention. The respective valves and hydraulic pumps provided in these hydraulic circuits are controlled by a known electronic control unit (not shown).

In FIG. 1, B / P is a brake pedal, M / C
Is a master cylinder, W / C is a wheel cylinder, and 30 is a gate valve. The inlet passage 15 formed in the gate valve housing 13 of the gate valve 30 is connected to the master cylinder M / C, and the outlet passage 16 formed in the gate valve housing 13 is connected to the wheel cylinder W / C.
Connected to C. Also, the gate valve housing 1
An anti-skid control circuit is connected between the pressure acting passage 14 and the pressure adjusting passage 17 formed in 3.

The anti-skid control circuit is composed of the following hydraulic circuit. That is, the pressure acting passage 14
Is connected to the reservoir 1 via a power supply valve 4, an accumulator 3 as a hydraulic pressure source, and a pump 2, and the pressure adjusting passage 17 is connected to the reservoir 1 via a decay valve 6. Further, the power supply valve 4 is connected to the pressure adjusting passage 17 via a hold valve 5. The hydraulic pressure of the accumulator 3 is detected by a pressure switch 7, and when the hydraulic pressure falls below a predetermined value, the pump 2 is drive-controlled so that a predetermined hydraulic pressure is constantly accumulated in the accumulator 3.

The power supply valve 4 is constructed as a two-position switching valve, and is normally in the A position as shown in the figure, and switches to the B position during antiskid control, and the hydraulic pressure of the accumulator 3 is changed to the pressure acting passage. 14 and the hold valve 5 can be operated. Further, the hold valve 5 and the decay valve 6 are also configured as a two-position switching valve, and are normally in the C position and the E position as shown in the drawing, and D, F depending on the skid state of the wheel during the anti-skid control. The liquid pressure from the accumulator 3 can be applied to the oil chamber 37 in FIG. 1 via the pressure adjusting passage 17 while switching to the position.

Next, the detailed structure of the gate valve 30 will be described. Inside the gate valve housing 13 as the main body of the gate valve 30, a fail-safe piston 20 and a gate valve seat 24, which are integrally screwed together with a screw 22, are provided. Is slidably provided. A hydraulic chamber 33 is formed between the fail-safe piston 20 and the gate valve housing 13, and the hydraulic chamber 33 communicates with the pressure acting passage 14. Further, a groove portion 28 and a land portion 29 following the groove portion 28 are formed on the outer circumference of the fail-safe piston 20. The groove 28 communicates with a valve chamber 32 formed in the failsafe piston 20 via a first passage 31 formed in the failsafe piston 20. The valve chamber 32 communicates with the second oil passage 21 in the gate valve seat 24 via the pressure reducing valve 50 as the second control valve.

Next, details of the first control valve and the second control valve will be described with reference to FIG. The groove portion 28 and the land portion 29 formed on the outer periphery of the fail-safe piston 20 are the first
It is connected to the inlet passage 15 via a cutoff valve 40 as a control valve. The cut-off valve 40 as a first control valve is composed of a cut-off valve seat 41, a cut-off valve plug 42, a ball pressing spring 43, a large diameter ball 44, and a small diameter ball 45. The ball as a body is pressed toward the valve seat 46 of the cutoff valve seat 41 by the ball pressing spring 43.

When the groove 28 is in the illustrated state (during non-anti-skid control), the ball 45 of the cut-off valve 40 rides from the groove 28 to the land 29, and the cut-off valve 40 is opened to open the inlet passage. The groove 15, the groove 28, and the outlet passage 16 are in communication with each other.

On the other hand, when the anti-skid control is started, the power supply valve 4 is opened, and the hydraulic pressure from the accumulator 3 is supplied into the hydraulic pressure chamber 33 through the pressure acting passage 14, the fail-safe piston 20 is activated. It moves to the left from the illustrated state under the action of pressure. As a result, the ball 45 of the cutoff valve 40 falls into the groove 28, the ball 44 abuts the valve seat 46 of the cutoff valve seat 41, and disconnects the communication between the inlet passage 15 and the groove portion 28.

The second control valve is formed by a valve seat formed on the gate valve seat and a ball valve 23 as a second valve body which is pressed against the gate valve seat 24 by a spring 27. A set spring 25 and a valve rod 26 for urging the gate valve seat 24 to the right in the drawing are arranged in the second oil passage 21.
The valve rod 26 is configured to abut a sleeve 34 fixed by a plug 35 in the gate valve housing 13, and when the gate valve seat 24 moves to the left side in the drawing together with the fail-safe piston 20 as described later. The ball valve 23 is pushed up to the valve chamber 32.
And the second oil passage 21 are communicated with each other.

Further, the control piston 11 is slidably provided in the sleeve 34. A guide rod 39 is fixed to the control piston 11,
The guide rod 39 is slidably fitted to the sleeve 34, and the control piston 11 is connected to the plug 3
5 is pressed against the sleeve 34 by the control spring 12 provided in the oil chamber 37 formed between the oil chamber 37 and the oil chamber 5. A decompression chamber 36 is formed between the control piston 11 and the sleeve 34. In addition, a passage 38 that connects the decompression chamber 36 and the flow path 21 is formed in the sleeve 34.

When the anti-skid control is started, the power supply valve 4 is opened, and the hydraulic pressure from the accumulator 3 is supplied into the hydraulic chamber 33 via the pressure acting passage 14, the fail-safe piston 20 acts on the hydraulic pressure. It moves to the left from the receiving state. As a result, the fail-safe piston 20 and the gate valve seat 24 are attached to the sleeve 34.
Since it moves to the left until it contacts the valve rod 26
Pushes up the ball 23 to connect the valve chamber 32 and the flow path 21. As a result, the brake fluid in the wheel cylinder W / C flows into the pressure reducing chamber 36 through the first passage 31, the valve chamber 32, the pressure reducing valve 50, the flow passage 21 and the passage 38, and the control piston 11 is attached to the set spring 12. The brakes on the wheels can be released while moving to the left against the power.

In this embodiment, the cutoff valve 40
As described above, the cut-off valve seat 4 is provided as shown in FIG.
If 2 is used also as the tube sheet for the brake pipe 55, the size of the device can be further reduced.

Since this embodiment is constructed as described above, the following operation is performed during normal braking, anti-skid control, and power failure. [During normal brake operation] In FIG. 1, the power supply valve 4 is in the A position shown in FIG. 1 during normal brake operation, and the pressure acting passage 14 formed in the gate valve housing 13 and the pressure adjusting passage 17 are connected to the accumulator 3 from the accumulator 3. Hydraulic pressure is not working. Therefore, the fail safe piston 20 and the control piston 1 are
No hydraulic pressure acts on 1, and the control piston 11 and the fail-safe piston 20 are in the illustrated state by the urging forces of the control spring 12 and the set spring 27. At this time, the first control valve (cutoff valve)
40 is open, and the second control valve (pressure reducing valve) 50 is closed.

Therefore, when the brake pedal B / P is operated to generate the hydraulic pressure in the master cylinder M / C in this state, the hydraulic pressure from the master cylinder M / C is changed to the inlet passage 15 →
It is supplied to the wheel cylinder W / C through the first control valve 40-> the groove 28-> the outlet passage 16. Thus, normally,
When the brake pedal is depressed, the hydraulic pressure of the master cylinder is supplied to the wheel cylinders through the oil passages, and the wheels are braked. Further, when the brake pedal B / P is released, the hydraulic pressure of the wheel cylinder W / C passes through the outlet passage 16, the groove 28, the first control valve 40, and the inlet passage 15 to the master cylinder M /.
It is returned to C and the brake is released.

[During Anti-Skid Control] When the wheel is in a skid state during brake operation, the power supply valve 4 is switched from the A position shown in the drawing to the B position by a signal from an electronic control unit (not shown). As a result, the accumulator pressure acts on the pressure acting passage 14 formed in the gate valve housing 13, and the fail safe piston 2
0 moves to the left in the figure against the biasing force of the set spring 25. By moving the fail-safe piston 20,
The ball 45 of the cutoff valve 40 falls into the groove 28, the first control valve 40 closes the flow path, and the valve rod 26 pushes up the ball 23 to open the second control valve 50.
The brake fluid in the wheel cylinder W / C is discharged through the outlet passage 16 →
Loosen the brake of the wheel while flowing into the valve chamber 32 → the second control valve 50 → the flow path 21 → the passage 38 → the decompression chamber 36 and moving the control piston 11 leftward against the biasing force of the control spring 12. You can

When the hold valve 5 and the decay valve 6 are in the C position and the F position in this state, a high hydraulic pressure from the accumulator 3 flows into the oil chamber 37 from the pressure adjusting passage 17, and this hydraulic pressure is the control piston 11. Is moved to the right in the figure and the brake fluid flowing into the decompression chamber 36 is discharged to the second position.
It can be supplied to the wheel cylinder W / C via the control valve 50 to apply a brake to the wheels, and the responsiveness at the time of control is improved. With the above operation, anti-skid control is performed while adjusting the hydraulic pressure in the wheel cylinder.

[During Power Pressure Failure] Further, if the device that generates power pressure during the anti-skid control fails, the high pressure from the accumulator 3 does not act on the fail-safe piston 20, and the fail-safe piston 20 moves to the set spring 25. The urging force of returns to the state of FIG. As a result, the second control valve 50 is closed, the first control valve 40 is opened, the outlet passage 16 and the inlet passage 15 are communicated with each other, and the brake is actuated by the hydraulic pressure from the master cylinder M / C as in the normal braking. Can be made. Therefore, in the present invention,
It eliminates the need for a special fail-safe valve mechanism for power failure.

[0029]

As described in detail above, according to the present invention,
During non-braking and during normal braking, hydraulic pressure does not act in the anti-skid control hydraulic piping, so hydraulic pressure does not act on the hydraulic piping used in the device or the seal part in the circuit. It is not necessary to use pressure resistant specifications for the seal part and the circuit itself. Further, since high hydraulic pressure does not act on the seal portion of the hydraulic circuit, deterioration of the seal portion can be prevented. Furthermore, in this device, in addition to good responsiveness during anti-skid control, even if the device that generates power pressure during anti-skid control fails, the master cylinder and wheel cylinders immediately communicate with each other. Since it is not necessary to provide a special fail-safe valve mechanism for installation, it is possible to prevent the device from becoming complicated and the cost from increasing. Further, according to the present invention, the valve portion for switching between the normal hydraulic circuit and the hydraulic circuit at the time of control is configured as a ball valve of a thrust valve seat that is easy to process, and the cutoff valve 40 is provided in the valve housing. It is possible to achieve further miniaturization, and since the valve in the cutoff valve 40 is composed of two balls, it is possible to obtain an excellent effect that the valve can be structured at low cost.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram of an anti-skid control device as an embodiment according to the present invention.

FIG. 2 is an enlarged view of a cutoff valve and a pressure reducing valve.

FIG. 3 is an explanatory view of another embodiment of the cutoff valve.

[Explanation of symbols]

 1 reservoir 2 pump 3 accumulator 4 power supply valve 5 hold valve 6 decay valve 7 pressure switch 11 control piston 12 control spring 13 gate valve housing 14 pressure acting passage 15 inlet passage 16 outlet passage 17 pressure adjusting passage 20 failsafe piston 21 passage 23 ball 24 gate valve seat 27 set spring 30 gate valve 32 valve chamber 36 pressure reducing chamber 37 oil chamber 40 first control valve (cut-off valve) 50 second control valve (pressure reducing valve) B / P brake pedal M / C master Cylinder W / C Wheel cylinder

Claims (7)

[Claims] 1. A master cylinder M / C and a wheel cylinder
The first control valve 40 is provided in the oil passage connecting the W / C and the second control valve 50 is provided in the oil passage connecting the wheel cylinder W / C and the decompression chamber 36. Is normally connected to the master cylinder M / C and the wheel cylinder W / C and is connected to the master cylinder M / C during anti-skid control.
And the wheel cylinder W / C are disconnected from each other, and the second control valve 50 normally operates the wheel cylinder W / C.
In an anti-skid control device having a configuration in which the communication between C and the decompression chamber 36 is cut off and the wheel cylinder W / C and the decompression chamber 36 are communicated during anti-skid control, the first control valve 40 is a gate valve. A fail-safe piston 20 that is slidably disposed in the body of 30 and moves by receiving hydraulic pressure from a hydraulic pressure source during anti-skid;
Groove 28 formed on the outer circumference of the fail-safe piston
The first valve element 44, 4 which closes the flow path by falling into the
The second control valve 50 is disposed in the failsafe piston and the dew formed inside the failsafe piston to open a flow path by the movement of the failsafe piston. An anti-skid control device comprising a valve body 23. 2. The second valve body is constituted by a ball valve which is disposed inside the fail-safe piston and which opens a flow path by pushing up a valve rod which is pushed up by the movement of the fail-safe piston. Antiskid control device as described. 3. The first valve body constituting the first control valve is composed of two balls having different outer diameters, and the ball having a large diameter contacts the valve seat to close the flow passage. The anti-skid control device according to claim 1. 4. The anti-skid control device according to claim 2, wherein the valve seat of the first control valve is also used as a tube seat for brake piping. 5. The first control valve and the second control valve are both configured to return to a normal position immediately when the hydraulic pressure from the hydraulic pressure source stops acting on the fail-safe piston. Item 1. The anti-skid control device according to Item 1. 6. The anti-skid control device according to claim 1, wherein the first control valve is arranged in a gate valve body, and the second valve body is arranged in a fail-safe piston. 7. The decompression chamber 36 is adjacent to an oil chamber 37 via a control piston 11, and the oil chamber 37
Is connected to the hydraulic pressure source 3 via the power supply valve 4 and the hold valve 5, and is connected to the reservoir 1 via the decay valve 6, and during the anti-skid control, the power supply valve 4 and the hold valve are connected. 5. The anti-skid control device according to claim 1, wherein the decay valve 6 is switched to control the hydraulic pressure in the oil chamber 37, thereby controlling the hydraulic pressure in the decompression chamber 36.