JPS592656B2 - Anti skid control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-skid control device that has a combination valve function and is capable of anti-skid control of rear wheel brakes even during rear partial braking and provides a good feeling.

Conventional combination valve bypass valves have had problems such as the O-ring becoming loose due to the bypass port.

The present invention does not cause problems such as stiffness in such cases, and also dissipates the power pressure in the actuator when the front brake is lost, bypassing it in the same way as when power pressure is lost, and unlike the case where anti-skid control cannot be performed, the present invention It is an object of the present invention to provide an anti-skid control device which enables anti-skid control by supplying high power pressure to an actuator and opening a cut valve of the actuator when the brake is lost, thereby bringing the actuator into the same state as a conventionally known actuator. be.

The present invention will be described below with reference to the embodiments shown in the drawings. FIGS. 1 to 3 are system diagrams showing detailed structures of the pressure reducing section main body of the actuator 1, the adjustment device, the bypass valve, and the defect detection device.

First, in Fig. 1, 2 is a brake pedal, 3 is a mask cylinder, 4 is a front wheel brake, 5 is a rear wheel brake, 6 is a hydrolink brake booster,
1 is a reservoir tank, 8 and 9 are orifices, 10 is a sensor, and 11 is a computer, and all of the above members are known.

12 is a control valve that operates according to an operation command signal from the computer 11; 13, 14, and 15 are brake fluid system piping; 1
6 to 25 indicate power hydraulic system piping, and dotted lines 26 to 29 indicate electric wires.

Further, in the actuator 1, 30 is a pressure reducing piston,
31.32 is a bypass valve piston, 33 is a small power piston, 34.35 is a ball valve, 36, 37, 3
8 is a valve seat, 39 and 40 are springs, 41 is an inlet from the mask cylinder 3, 42 is an outlet to the rear wheel brake 5, and 43 and 44 are power hydraulic inlets and outlets.

Further, 45 is a pressure regulating piston, 46 is a pressure regulating spool, 41 is a spring, 48 is an outlet to the actuator 1, 49 is an unloader valve, and 50 is an accumulator.

Note that the state shown in FIG. 1 shows a state in which the engine is started, the pump 51 is operating, and the brake is not applied.

Now, when the brake pedal 2 is depressed during normal braking operation, the pressure in the hydrolink brake booster 6 increases, the mask cylinder 3 is pressurized, and the front wheel brake 4 is activated, and the rear wheel brake 5 is connected from the pipe 14 to the inlet 4.
1→chamber 52→chamber 53→passage 54→chamber 55→piping 15 through the actuator 1.

On the other hand, when the engine is started, the pump 51 operates and sends power pressure to the regulating valve of the actuator 1, and the pressure regulating spool 46 moves to the right against the spring 47, and the edge portion 200 of the pressure regulating spool 46 moves to the right. The edge portion 201 of the land of the body comes into contact with the actuator, and the pressure inside the actuator is maintained at Pl (FIGS. 1 and 4).

If the load of the spring 47 at this time is 83, P HX
To be decided on A7-83.

Next, when the brake is applied, the mask cylinder pressure PM (
(P, xA7) <83+(PMXA6)I,
The pressure regulating piston 45 moves to the left to close each edge portion 200 and 2.
01 is released, then pressure enters from the accumulator 50 and the pressure PR in the chamber 56 rises (PMXA6)+83<(PR
When XA7)) is reached, the edges come into contact again.

When PM further increases pressure ((P MXA6) +83>
(In July, each edge part separates and repeats this operation to increase the pressure PR to the actuator 1.)

The pressure relationship at this time is that at point G (PH=P6) in FIG. 4, the pressure reducing piston 69 of the pressure reducing valve moves to the right, and the edge portion 202 of the pressure reducing piston 69 and the edge portion 203 of the land of the body are in contact with each other.

Here, if the load of the spring 70 is 84, the point G has passed again, and if the pressure in the chamber 100 is PD, PR will further increase, ((PDXA)<PRX(AQ A8)
+84), the decompression piston 69 is pushed to the left, each edge part 202 and 203 are separated, and PR is moved to the chamber 100.
is introduced into the chamber 100, but the pressure PD in the chamber 100 is ((PD XA
)>PRX (AQ A8)+841, each edge portion contacts again.

By repeating this operation, PD is reduced to a pressure lower than PR.

The pressure relationship at this time is that the balance between the pressure reducing piston 30 and the power piston 59 is such that the load of the spring 39 is 8. Then, when the pressure increases further and passes point A in Figure 4, the adjusted pressure PD>P2 (mask pressure PM>Po), and ((P
MXA2) +8. >(PoXA3) )t, r
The pressure reducing piston 30 and the power piston 59 move to the left, the ball valve 34 is pressed against the valve seat 36 by the spring 39, and the cut valves 34 and 36 are closed.

When PM is further increased in pressure, the pressure pw in the chamber 53 does not change, but ((PM X A + ) + (Pw XA2) + J
When <(PWXAI) + (PDXA3)l, the pressure reducing piston 30 and the power piston 59 move to the right, the ball valve 34 is pushed up, the pressure in the chamber 52 is introduced into the chamber 53, and Pw increases.

However, Pw is ((PMXAI) + (PWXA2) +
8. >(PWXA, ) + (PI)XAa) ), the pressure reducing piston 30 and the power piston 59 move to the left, and the cut valve is closed again.

The opening and closing of this cut valve is repeated, and the rear wheel brake pressure Pw is reduced.

Proportioning valve characteristics can be obtained by determining various dimensions such that the balance equation at this time is as follows.

Next, the operation when normal braking is released will be explained.

When the brake pedal 2 that has been depressed first begins to be released, the mask pressure PM decreases, so the pressure regulating piston 45 and the pressure regulating spool 46 move to the right, and the oil in the chamber 56 is discharged to the reservoir γ. The pressure PR in the chamber 56 also decreases.

When the pressure PR in the chamber 5G decreases, the spool 46 returns to the left, but
When the mask pressure PM further decreases, the pressure in the chamber 56 decreases again, and by repeating this, as PM decreases, PR decreases, and of course PD also decreases, so PD and PM are determined by line 9 in FIG. It decreases almost in line with .

Also, when PH1, that is, the pressure in the chamber 58, decreases, PM also decreases, but since PM>Pw, it does not flow from the chamber 53 of the actuator 1 to the chamber 52 (PDXA3''PWXA2) (7) Balance item decompression histone 30 As the power piston 59 moves to the left, Pw decreases as PD decreases.

PD<P2 (PM<PO), that is, after passing point A, PM further decreases, and: (PM
WXA, )), the ball valve 34 is activated by the hydraulic pressure in the chamber 53.
Since it flows into the open chamber 52, Pw also decreases.

At the same time, the decompression piston 30 and the power piston 59 begin to return to the right, and finally push up the ball valve 34 to maintain communication between the chambers 52 and 53.

Next, during anti-skid control, when the rear wheel brake 5 is about to lock up the rear wheels at any time during the braking process, the computer 11 turns on the solenoid 60.
When the signal is output and the solenoid 60 is energized, the chambers 56 and 58 are cut off and the chamber 58 and the reservoir 1 are communicated with each other.
The pressure in chamber 58 decreases.

Therefore, the pressure in the decompression chamber 53 pushes the decompression piston and the power piston 59 to the left, so the ball 34 is pressed against the valve seat 36 by the spring 39, and the volume of the letter 53 increases, so the pressure in the chamber 53 decreases. , the braking of the rear wheel brake 5 is weakened.

Also, when the solenoid 60 is energized, the solenoid 6
1 is also energized, and the oil in the chamber 58 does not pass through the orifice 8, so the depressurization speed is fast.However, when the solenoid 61 is de-energized by a command from the computer 11, the oil in the chamber 58 passes through the orifice 8, so the depressurization speed decreases. Become slow.

Next, when the rear wheel is unlocked, the solenoid 60 is de-energized by a signal from the computer 11, and the solenoid 61 is energized, so that the chamber 58 is pressurized again and the power piston 59 and decompression piston 30 is pushed to the right, the pressure in the decompression chamber 53 is increased, and the braking of the rear wheel brake 5 is strengthened.

Next, when the solenoid 61 becomes de-energized, the oil passes through the orifice 8, so the pressure increase rate becomes slow.

Repeat the above steps to perform anti-skid braking.

Next, in the case of a power pressure deficit, for example, if the power pressure decreases due to a defect in the pump 51, etc., the actuator tough chambers 58 and 6
2 pressure is lowered and the spring 39 presses the ball 34 onto the valve seat 36, and the spring 40 separates the ball 35 from the valve seat 38 and presses it onto the valve seat 31, so that the mask cylinder 3→pipe 14→inlet hole 41
→Chamber 52→Chamber 63→Outlet 42→Pipe 15 communication is ensured, and braking is guaranteed.

Next, referring to FIG. 1, the case when the front brake is missing will be explained.

If the front brake system is damaged (P MX A33
), the alarm main piston 63 moves to the right and comes into contact with the switch contact 64, turning on the switch, and the lamp 65 lights up to notify the driver of the defect.

At the same time, the alarm auxiliary piston 66 moves to the left by the force (2MXA34).

Therefore, if the setting is made so that Valves 34 and 36 are opened;
Anti-skid control becomes possible.

Next, due to the force caused by the breakage of the rear brake system, both the alarm main piston 63 and the alarm auxiliary piston 66 move to the right and come into contact with the switch contact 64, causing the switch o
n, the lamp 65 lights up to notify the driver of the defect.

Next, to explain the second embodiment shown in Fig. 2, the regulating valve in this uses an open loop valve, and the booster pressure PB is balanced by the regulating valve, but other functions are as shown in Fig. 1. This is the same as in the embodiment.

Next (to explain the third embodiment shown in Fig. 3), the operation and effects of the normal braking operation, normal braking release, anti-skid braking, and power pressure loss are the same as those of the embodiment shown in Fig. 1. The same is true for .

Also, in Fig. 3, 11 is a sleeve, 12 is a guide, and 73
is a plunger, 74 is a check valve, 75 is a check valve seat,
76 is a spring.

Now, in Figure 3, if the front brake system is missing,
If the load of the spring 76 is set to S3O, the force causes the alarm auxiliary piston 66 and the plunger 73 to move to the left, and in order to separate the ball valve 74 from the valve seat 75, the regulating valve and the actuator 1 communicate with each other, and high pressure power is applied to the actuator 1. The ball valve 34 is opened by supplying pressure to perform anti-skid control.

Next, if the rear brake system is damaged, the alarm main piston 63
PMX ((A36 A3□) (A32 A3
Since the pressing force due to the hydraulic pressure in 1)) acts in the right direction, the main piston 63 moves to the right and the switch is turned on, lighting up the lamp 65 to notify the driver of the defect.

As described above in detail, the present invention supplies high power pressure to the actuator to open the on-off valve of the actuator and eliminate the proportioning valve function when the front wheel brake is lost.

That is, it is possible to perform anti-skid control in the same state as a conventionally known actuator.

As described above, the present invention has a combination valve function, and can perform anti-skid braking of the rear wheel brake even during rear partial braking, and can perform operation with good feeling.

[Brief explanation of drawings]

1, 2, and 3 are system diagrams of an anti-skid control device showing embodiments of the present invention, and FIG. 4 shows the mask cylinder pressure PM and the adjusted pressure PR (adjusted pressure reduced by the pressure reducing valve). Fig. 5 is a diagram showing the relationship between the mask cylinder pressure PM and the wheel brake cylinder pressure pw. Explanation of the main parts of the figure, 1...actuator,
2...Brake pedal, 3...Mask cylinder, 4...Front wheel brake, 5
... Rear wheel brake, 6 ... Hydraulic brake booster, 7 ... Reservoir rick, 11 ... Computer, 12 ...
... Control valve, 30 ... Pressure reducing piston, 31,
32...Bypass valve piston, O...
・Small power piston, 34, 35... Ball valve, 39, 40... Spring, 45...
...Pressure regulating piston, 46...Pressure regulating spool,
47...Spring, 50...Accumulator, 51...Pump, 52.53.55
．． 56... Chamber, 63... Alarm main piston, 64... Switch contact, 65...
Lamp, 66...Alarm auxiliary piston, 69...
... pressure reducing piston, 70 ... spring,
73...Plunger, 74...Check valve.

Claims (1)

[Scope of Claims] 1. A brake mask cylinder, a defect detection device for detecting a defect in a front wheel brake system that performs a braking action using the braking pressure from the mask cylinder, and one or more components that perform a braking action using the braking pressure from the mask cylinder. a rear wheel brake, an actuator disposed between the mask cylinder and the rear wheel brake that reduces and increases the braking pressure of the rear wheel brake according to the skid state of the wheel during braking, and decreases and increases the pressure on the actuator; A control means for issuing a command signal, a pressure source capable of generating power pressure for the actuator, supplying a constant pressure to the actuator when not braking, and supplying the power pressure in proportion to the braking pressure when braking, and controlling the mask cylinder and the rear wheel. A pressure regulating valve that adjusts the pressure to a level sufficient to open an on-off valve provided in an actuator that opens and closes communication with a brake, and supplies the actuator with a regulating pressure that is set and arranged between the pressure regulating valve and the actuator. When the adjustment pressure is less than the set adjustment pressure, the outlet adjustment pressure is increased at the same rate of increase as the inlet adjustment pressure, and when the inlet adjustment pressure exceeds the set adjustment pressure, the increase rate of the outlet adjustment pressure is increased by the increase rate of the inlet adjustment pressure. When the braking pressure is lower than the set braking pressure by the action of the outlet adjustment pressure of the pressure reducing valve, the on-off valve is opened to increase the outlet braking pressure of the actuator at the same increase rate as the inlet braking pressure 8, and the actuator When the inlet braking pressure of the actuator exceeds a set braking pressure, the actuator opens and closes the on-off valve to make the rate of increase in the outlet braking pressure of the actuator smaller than the rate of increase in the inlet braking pressure, which is linked to the defect detection device. An anti-skid control device comprising means for stopping the operation of the pressure reducing valve. 2. The anti-skid control device according to claim 1, wherein the defect detection device is formed by a differential valve that operates by detecting a difference in braking pressure between a front wheel brake system and a rear wheel brake system. 3. The means for stopping the operation of the pressure reducing valve is such that the acting force of the piston of the differential valve, which is operated by the braking pressure of the rear wheel brake system as a result of the front wheel brake system defect, is greater than the acting force of the piston of the pressure reducing valve, which is activated by the adjustment pressure. 3. The anti-skid control device according to claim 2, further comprising means for putting the pressure reducing valve into a non-operating state. 4 A means for stopping the operation of the pressure reducing valve is placed in parallel with the pressure reducing valve by connecting the inlet and outlet sides of the pressure reducing valve, and the valve is opened only when the outlet regulated pressure of the pressure reducing valve becomes higher than the inlet regulated pressure. 2. The anti-skid control device according to claim 1, further comprising means for opening a check valve.