JPS592655B2 - Anti skid control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention aims to provide a hydraulic anti-skid control device that has a combination valve function and has a good feeling.

In the conventional combination valve bypass valve,
There were 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 eliminates the actuator's proportioning function when the front is missing, allowing the mask cylinder pressure to be directly supplied to the wheel brake, which greatly reduces the braking distance when the front is missing. It is an object of the present invention to provide an anti-skid control device which eliminates drawbacks such as the long length of the skid.

The present invention will be explained below with reference to the embodiments shown in the drawings. Figures 1 to 3 are system diagrams showing the detailed structure of the actuator's pressure reducing part body, adjustment device, bypass valve, defect detection device, and switching valve. be.

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, 39.40 is a spring, 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, 47 is a spring, 48 is an outlet to the actuator 1, 49 is an unrotor 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 hydraulic 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 adjusting device 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 part 201 of the land of the body comes into contact with the pressure inside the actuator of P,
(Figure 1).

If the load of the spring 47 at this time is 82, then P1×A
3-82.

Next, when the brake is applied, the mask cylinder pressure PM (
(P + X A5) <82 + (P M x A4
)) To f, i, the pressure regulating piston 45 moves to the left and separates the respective edge portions 200 and 201, and then pressure enters from the accumulator 50 and the pressure PR in the chamber 56 rises, ((P M
When XA4) +82 <CP RxA3)), the edges come into contact again.

When the PM pressure increases further, ((P M X A4) +82
> (P B
to rise.

Therefore, the pressure relationship at this time is: If the balance between the pressure reducing piston 30 and the power piston 59 is 81, the load of the spring 39 is then increased to more than point A in FIG. 8, that is, the adjustment pressure PR> When P2 (mask pressure PM>Po), [(P MXA2 ) + S
s≧PRXA3), the pressure reducing piston 30 and the power piston 59 move to the left, the ball valve 34 is pushed by the valve seat 36 by the spring 39, and the cut valve 34
．． 36 closes.

Further, the pressures of PM and PR are increased, and the pressure pw of the chamber 53 does not change, but ((P MXAI )+(PWXA2)+S+<
(PWXAI) + (PBXA3))
Then, 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 guided to the chamber 53, and pw increases.

However, Pw is f (P M X AH) + (P
wX A2 ) + SI>(PwX Al ) + (P
When the pressure rises to RXAa)), the pressure reducing piston 30 and the power piston 59 move to the left, and the cut valve is closed again.

By repeating this opening and closing, the rear wheel brake pressure Pw is reduced.

The balance equation at this time is PMXAI = P RXAa
.=(4) (Fig. 4 (4)), and by determining various dimensions such that this is translated in parallel so as to intersect with point A, a proportioning valve characteristic can be obtained.

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 increases and the reservoir 1
The pressure PR in the chamber 56 also decreases.

When the pressure PR in the chamber 56 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 this process is repeated. From this, as PM decreases, PR decreases, and of course PM also decreases, so PR and PM decrease approximately along the two lines in FIG. 4.

Furthermore, when P, that is, the pressure in the chamber 58, decreases, PM also decreases.
Since PM>Pw, the flow does not flow from the chamber 53 to the chamber 52 of the actuator 1, and the pressure reducing piston 30 and the power piston 59 move to the left due to the balance of (PRxA3-2wXA2), so Pw follows the decrease in PR. descend.

P R<P2 (P M<PO), that is, P further decreases after passing point A, and f (P M XA3 ) +SJ <(
When PW XAI)), the liquid's pressure in the chamber 53 pushes the ball valve 34 and flows into the open chamber 52, so 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 braking, when the rear wheel brake 5 is about to lock up the rear wheel at any time during the braking, 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 7 are communicated with each other.
The pressure in chamber 58 decreases.

Therefore, the pressure in the decompression chamber 53 pushes the decompression piston 30 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 character 53 increases, so the pressure in the chamber 53 decreases. , the braking of the rear wheel brake 5 is weakened.

Also, at the same time that 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 subsequently de-energized by a command from the computer 11, the oil in the chamber 58 passes through the orifice 8, so the decompression speed becomes 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 are activated. 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 chambers 58 and 6 of the actuator 1
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 37, so that the mask cylinder 3 → pipe 14 → entry hole 41
→Chamber 52→Chamber 63→Outlet 42→Pipe 15 communication is ensured, and braking is guaranteed.

Next, to explain what happens when the front brake is missing with reference to Figure 1, when the front brake is missing, actuator 1
The provisioning valve function of the brake is eliminated, and the mask cylinder pressure is directly transmitted to the rear wheel brake 5.

In Fig. 1, 64 is a defect detection device, which is inside the body 65? A main alarm piston 66 and an auxiliary alarm piston 67 are inserted here, and a switching valve portion 68 integrated with the auxiliary alarm piston 67 is also inserted.

A plug 69 is screwed into the opening at one end of the body 65, and the switch contact 1 of the alarm circuit 70 is connected to the plug 69.
1 is attached to the insulating member 12, and the switch contact 71 faces the small diameter portion 13 on the right side of the alarm main piston 66.

Now, if the front brake system is damaged, the cross-sectional area A22 of the large diameter part of the alarm main piston 66, the cross-sectional area A21 of the small diameter part,
Between the cross-sectional area A2 of the large diameter part of the alarm auxiliary piston 6γ and the cross-sectional area A25 of the small diameter part, (A24 A25) > (
Since there is a setting for A22 A2 +), PMX (A2 +)
24 A25)>PMX(A22 A21).

Therefore, since the pressing force due to the hydraulic pressure acting on the alarm auxiliary piston 61 from the pipe 14 is larger than the pressing force due to the hydraulic pressure acting on the alarm main piston 66, the alarm main piston 66
is pushed by the alarm auxiliary piston 67 and moves to the right, and when its small diameter portion 73 comes into contact with the switch contact 11, the switch is turned on, and the radiator 14 lights up to notify the driver of the defect.

At the same time, the switching valve section 68 also moves to the right, so its spool section 15 comes into contact with the land 16 of the body, and the spool section 77 separates from the land 78 of the body, so that the pressure in the chamber 62 is reduced by the pressure in the pipe 22.
, chamber 79 and pipes 80, 25 into the reservoir 1.

Therefore, since the bypass valve pistons 31 and 32 are moved to the left by the spring 40, the ball valve 35 is separated from the valve seat 38, and the mask cylinder pressure is reduced to the pipe 14,
It is directly supplied to the rear wheel brake 5 via the inlet 41, chambers 52, 63, outlet 42, and pipe 15.

Next, when the rear brake system is damaged, the pressure from the oil pressure (PMxA24) acts on the warning auxiliary piston 61 in the left direction through the pipe 13, so the warning auxiliary piston 67 remains at the position shown in the figure. , the main piston 66 moves to the right, the switch is turned on and the lamp 74 lights up, alerting the driver to the fault. Inform.

Fig. 2 shows a second embodiment different from Fig. 1, but the functions and effects during normal braking, normal braking release, anti-skid braking, power pressure deficiency, and rear brake system deficiency are as follows. This is the same as in FIG.

In addition, when the front brake system is defective, it operates in the same way as in the case shown in FIG.
is discharged from the chamber 19 through the pipes 81 and 82 to the reservoir 7, so that the regulated pressure disappears and the ball valve 35 moves to the left as in the case of FIG.
4 is also crimped onto the valve seat 36.

Next, FIG. 3 shows a third embodiment, in which an open/closed valve is used as the adjusting device, and the booster pressure is used as the control means for the adjusting device.

Other operations are the same as in FIG. When the front brake system is defective, it operates in the same manner as in the case shown in FIG. Since the liquid is discharged to the reservoir 7 via the ball valve 35 , the ball valve 35 moves to the left and the ball valve 34 is also pressed against the valve seat 36 .

As explained in detail above, according to the present invention, it has a good feeling and has a proportioning valve function, and when the front brake is lost, the actuator's proportioning valve function can be eliminated and mask cylinder pressure can be directly supplied to the rear wheel brake. Therefore, the braking distance when the front brake is missing can be made much shorter than when the actuator still functions as a proportioning valve even when the front brake is missing.

[Brief explanation of drawings]

1, 2, and 3 are system diagrams of an anti-skid control device showing an embodiment of the present invention, FIG. 4 is a diagram showing the relationship between mask cylinder pressure PM and adjustment pressure PR, and FIG. The figure is a brake fluid pressure characteristic 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 petal, 3... Mask cylinder, 4... Front wheel brake,
5...Rear wheel brake, 6...
Hydraulic brake booth, 7...Reservoir tank, 10...Sensor, 11...
・Computer, 12... Control valve, 30...
...Pressure reducing piston, 31.32...Bypass valve piston, 34,35...Ball valve, 39...Spring, 45...Pressure regulating piston , 46...pressure adjustment spool, 47...
... Spring, 51 ... Pump, 52,5
3, 58, 62... Chamber, 64... Defect detection device, 66... Alarm main piston, 67...
...Alarm auxiliary piston, 68...Switching valve part.

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 a pressure decrease and increase command signal to the actuator. a pressure source capable of generating power pressure for the actuator; supplying a constant pressure to the actuator during non-braking, and adjusting the power pressure to an adjustment pressure proportional to the braking pressure during braking to control the actuator; an adjustment device for supplying the adjustment pressure to the rear wheel brake, which communicates the decompression chamber provided in the actuator with the rear wheel brake when the adjustment pressure is being supplied; a bypass valve that cuts off communication between the mask cylinder and the rear wheel brake, and when the adjustment pressure disappears, cuts off communication between the pressure reduction chamber and the rear wheel brake, and also allows the mask cylinder and the rear wheel brake to communicate; When the braking pressure is lower than the set braking pressure due to the action of pressure, an on-off valve that opens and closes communication between the mask cylinder provided in the actuator and the decompression chamber is opened 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 reaches a set braking pressure or more, the opening/closing valve is opened and closed 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; An anti-skid control device characterized by comprising means for extinguishing the regulated pressure by a switching valve interlocked with a defect detection device. 2. A switching valve is disposed between the regulator and the bypass valve,
2. The anti-skid control device according to claim 1, wherein when the defect detection device is activated, the switching valve cuts off communication between the regulating device and the bypass valve, and allows communication between the bypass valve and the reservoir. 3. A patent claim characterized in that a switching valve is disposed between a regulating device and a bypass valve and an actuator, and when the defect detection device is activated, the switching valve eliminates the regulating pressure in the bypass valve and closes the on-off valve. The anti-skid control device according to item 1. 4 A switching valve is arranged between the pressure source and the regulating device, and when the defect detection device is activated, the switching valve eliminates the regulating pressure in the bypass valve, and also eliminates the regulating pressure in the actuator to close the on-off valve. 2. The anti-skid control device according to claim 1, wherein the anti-skid control device is characterized in that: