JPS592654B2 - Anti skid control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-skid control device, and an object of the present invention is to provide an anti-skid control device that has a proportioning valve function, is inexpensive, and has a good feel.

Conventionally, it has been proposed that a proportioning valve (in the form of a combination valve) is arranged between a mask cylinder and a wheel cylinder, and an actuator is arranged between the proportioning valve and the wheel cylinder.

Furthermore, in Japanese Patent Application No. 50-83340 previously filed by the present applicant, in an actuator that uses the booster pressure provided by a hydraulic brake booster as power pressure for the actuator, the booster pressure is reduced, and the actuator is used to brake the rear wheel. proposed an anti-skid control device that reduces the pressure of (or if the hydraulic brake booster was changed), the specifications of the actuator etc. had to be changed each time.

Furthermore, in conventional proportioning valves, when changing the slope of the PM-Pw diagram, there were many performance problems in changing the seal portion, so it was not possible to change the large diameter portion of the piston.

Therefore, the small diameter portion was changed, but in this case the cup had to be changed.

The present invention has been proposed to eliminate the above-mentioned conventional drawbacks, and has a proportioning valve function added to the actuator. Since the ball valve and valve seat of the cut valve are closed or only slightly opened, pressure reduction during anti-skid control is performed immediately, improving responsiveness and reducing the valve seat. The decrease in mask cylinder pressure due to the increase in volume corresponding to the lift stroke is almost eliminated, resulting in less pedal shock and improved performance.Moreover, the PM-Pw diagram can be easily changed by simply changing the piston diameter of the pressure regulating piston. It is an object of the present invention to provide an anti-skid control device that can change the gradient and is easy to handle.

Embodiments of the drawings will be described below. FIGS. 1 to 7 and 12 are system diagrams of an anti-skid control device showing embodiments of the present invention. This figure shows the details of the pressure reducing valve) and the bypass valve, which is a safety device in the event of power pressure loss.

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 hydraulic brake booster,
7 is a reservoir tank, 8 and 9 are orifices, 10 is a sensor, and 1161 is a computer. All of the above members are known.

12 is a control valve that operates according to the operation command signal from the computer 11; 13° and 14.15 are brake fluid system piping;
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 are bypass valve pistons, 33 are small power pistons, 34, 35 are ball valves, 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.
It operates via the actuator 1 as follows: 1-→chamber 53→passage 54→chamber 55→piping 15.

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 Pl.
(Figure 1).

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

Next, when the brake is applied, the mask cylinder pressure PM (
P1 × A5 × S2 + (2MXA4)), the pressure regulating piston 45 moves to the left and separates each edge portion 200 and 201, and then pressure enters from the accumulator 50, and the pressure PR in the chamber 56 rises, (( 2MXA4)+S2〈(P8×
At A5)), the edges come into contact again.

When the PM pressure increases further, ((2MXA4)+82>(P
R,

Therefore, the pressure relationship at this time is (P
If the load of the spring 39 is 81, the balance of the part is (P
XA2) +S, -P□×A3... (1) (Fig. 8 (1)) Next, the pressure is increased to more than point A in Fig. 8, that is, the adjusted pressure PR>P2 (mask pressure PM>PO ), then (
(PMXA2) +S1>PR,
6 to close the cut valves 34 and 36.

PP is further increased in pressure, and the pressure Pw in the chamber 53 changes, but ((PMXAl) + (PWXA, 2)
1<(PwX kl) + (PR,XAs)'
r, the pressure reducing piston 30 and the power piston 5
9 moves to the right, the ball valve 34 is pushed up and the chamber 5
2 pressure is introduced into the chamber 53, and Pw increases.

However, PW is ((PMxAl)+(PWXA2)
+81〉(PWXAl) + (PR,XA3)
When the pressure rises to 'r, 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.

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, so that the pressure in the chamber 56 decreases. PR, also goes down.

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 by repeating this, PR, decreases as PM decreases, so PR, and PM are approximately equal to line (2) in Figure 8. It goes down as well.

Also, when P□, that is, the pressure in the chamber 58, decreases, PM also decreases, but since PM is less than PW, it does not flow from the chamber 53 of the actuator 1 to the chamber 52, and the amount of (P□×A3-PW×A2) Since the decompression piston 30 and the power piston 59 move to the left in balance, Pw is PR.

decreases as .

P□P2 (PMPPD, that is, after passing point A, the PM further decreases and becomes ((PMxAI)+81<(PwXAI)), the fluid pressure in chamber 53 pushes the ball valve 34 and opens chamber 5
2, 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 wheels in the braking example described above, the computer 11 turns on the solenoid 60.
When the signal is output and the solenoid 60 is energized, the chamber 5"6
and 58 are shut off, and the chamber 58 and reservoir 7 are communicated with each other, so that the pressure in the 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 as the solenoid 60 is energized, the solenoid 61
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, so the chamber 58 is pressurized again and the power piston 59 and decompression piston 30 are 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.

FIG. 2 shows a different embodiment from FIG. 1, in which the unloader valve 49 and accumulator 50 of FIG. 1 are removed and booster pressure is utilized.

In FIGS. 2, 9, and 11, during normal braking operation, the booster pressure is set to PB=(axPM)+P, (7) ((7) in FIG. 9).

When the pressure becomes higher than point F, it is adjusted by the adjustment device, so (PMXA4) + 52 = PRXA5... (2) (9th
Figure (2)).

Note that other functions are the same as in the embodiment shown in FIG. 1 above.

Next, FIG. 3 shows a third embodiment, in which 64 is an accumulator, 65 is a flow divider, 66° and 67 are check valves, and 6
8 is IJ IJ-Fvalve.

Now, the embodiments shown in Figs. 3, 10, and 11 are for the case where a pressure reducing valve is used, and when the normal braking operation is used, the load of the spring 4γ is set to 83 as in the embodiments shown in Figs. 1 and 8. P1×A7=83.

When braking, (PMXA6) + 83 = (PRXA7)...
...(8) (Fig. 10 (8)) Then, the pressure reducing piston 69 of the Yoshi pressure reducing valve, which reaches point G, moves to the right.

Here, if the load of the spring 70 is 84, then P6 x A3-84. Also, if the pressure reduced by the pressure reducing valve after passing the G point is PD, then PDXA, = PR x (A, -A8) + 84...・
(9)' (8) and (91 formula).

Note that the other functions are the same as those of the embodiment shown in FIG.

Next, FIG. 4 shows the fourth embodiment.
The embodiment shown in Fig. 11 uses the booster pressure as a control means for the adjustment device, and the booster pressure is expressed as P = (ax pM) + b ・−・−uo)
The balance of the bolt adjustment device is (P XAIo) + S2 - (P, (, XA5) - -
・-old) From formulas (10) and (11), (a XPMxAIO) + (82+ (b XAt
o) )-P□×A5...(2) (Fig. 8(
2)).

Note that other effects are the same as in the case of FIG.

Next, although FIG. 5 uses an oven valve as an adjustment device, there is no difference in operation and effect from the embodiment shown in FIG. 1.

Next, the embodiment of FIG. 6 uses a relief valve 6 instead of the spring 47 that maintains a constant pressure in the embodiment of FIG.
8 is used, but there is no difference in operation and effect from the embodiment shown in FIG.

FIG. 7 shows a seventh embodiment, in which an open-closed valve is used as the adjustment device, but there is no difference in operation and effect from the embodiment shown in FIG.

Next, FIG. 12 shows the eighth embodiment, in which the brake pressure can be matched according to an ideal diagram by two-stage bending, and the cut valve 34 of the actuator comes into contact with the valve seat 36 at a low pressure, so that the pedal shock during anti-skid is reduced. can be further prevented.

In the embodiments shown in Figs. 12, 13, and 14, if the load of the spring 47 is °S5 and the load of the spring TO is 86, then P1 x A12 = 85. If it passes (Po < P < P 1o)
The cut valve closes and performs a proportioning valve function similar to the embodiment of FIG.

This is based on equations (3) and (20) used in the explanation of FIG. 1 above.

When the pressure increases further and reaches PR-P1□ (point K), the pressure reducing piston 69 of the pressure reducing valve moves to the right.

The relational expression at this time is (PH,

The balance equation at this time is 6 P = P (Pressure PR in the chamber 58 in equation (3) is
D Since it is PD in this eighth embodiment), Pw×(
A2 At ) = P X (x X A3
A1 )+('y XA3 St)・・・・・・(
23) (FIG. 14 (23)) If the specifications are determined so that the line diagram of equation (4) intersects at point Q, the necessary characteristics can be obtained.

Since the present invention is configured as explained in detail above,
Since the actuator has a proportioning valve function, it can be made into an effective anti-skid control device that is inexpensive, compact, lightweight, and highly reliable.

In addition, the pressure on the rear wheel brake cylinder side is reduced by slightly opening and closing the cut valve of the actuator.
Since the ball valve and valve seat of the cut valve are closed or only slightly opened, pressure reduction during anti-skid control is immediate, responsive, and equivalent to the stroke of the valve lift. Since there is almost no decrease in mask cylinder pressure due to an increase in volume, pedal shock can be reduced and performance can be improved.

Furthermore, the present invention can be used in any system arranged and piped in any way, and the slope of the PM-PW diagram can be easily changed by simply changing the piston diameter of the pressure regulating piston. This has advantages such as simplicity.

[Brief Description of the Drawings] Figs. 1, 2, 3, 4, 5, 6, 7, and 12 represent the first to eighth embodiments of the present invention, respectively. A system diagram of the anti-skid control device showing the
, 4, 5, 6, and 7 are diagrams showing the relationship between mask cylinder pressure P and adjustment pressure PR, and FIG. 9 is a diagram showing the relationship between mask cylinder pressure P and adjustment pressure PR (or booster pressure) in FIG. Figure 10 is a diagram showing the relationship between the mask cylinder pressure P and the adjusted pressure PR (and the adjusted pressure PD reduced by the pressure reducing valve) in Figure 3. The diagrams are brake pressure reduction characteristic diagrams in Figures 1, 2, 3, 4, 5, 6, and 7, and Figure 13 is a diagram showing the relationship between mask cylinder pressure PM and wheel brake cylinder pressure PW. Mask cylinder pressure P and adjustment pressure PR in Fig. 12, (
FIG. 14 is a brake fluid pressure characteristic diagram in FIG. 12, showing the relationship between the mask cylinder pressure PM and the wheel brake cylinder pressure PW. FIG. 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 tank, 10... Sensor, 11...
・Computer, 12... Control valve, 30...
... pressure reducing piston, 34 ... ball valve,
39...Spring, 45...Pressure regulating piston, 46...Pressure regulating spool, 47...
... Spring, 50 ... Accumulator, 5
1...Pump, 52゜53...Chamber, 5
9...Power piston.

Claims (1)

[Claims] 1. A brake mask cylinder, one or more rear wheel brakes that perform a braking action using braking pressure from the mask cylinder;
An actuator disposed between the brake mask cylinder and the rear wheel brake, which reduces and increases the braking pressure of the rear wheel brake according to the skid state of the wheel during braking, and a decrease/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; It has a regulating device that supplies
When the braking pressure is equal to or less than the set braking pressure due to the action of the adjustment pressure, an on-off valve provided in the actuator that opens and closes communication between the brake mask cylinder and the rear wheel brake is opened, and the braking pressure at the outlet of the actuator is transferred to the inlet. The braking pressure is increased at the same rate of increase as the braking pressure, and when the inlet braking pressure of the actuator exceeds the set braking pressure, the opening/closing valve is opened and closed to change the rate of increase of the outlet braking pressure of the actuator to the rate of increase of the inlet braking pressure. An anti-skid control device characterized in that it has means for making it smaller. 2. Claim 1, characterized in that the braking pressure generated by the brake mask cylinder is used as the operating means for operating the throttle valve means of the regulating device that adjusts the power pressure to a regulating pressure proportional to the braking pressure. Anti-skid control device as described in section. 3. The operating pressure of the hydraulic brake booster, which operates the brake mask cylinder in response to the pressing force on the brake pedal, is used as the operating means for operating the throttle valve means of the adjustment device that adjusts the power pressure to an adjustment pressure proportional to the braking pressure. An anti-skid control device according to claim 1, characterized in that: 4. A patent characterized by using a closed valve that is kept closed when not braking and opened according to the braking pressure when braking, as a throttle valve means of an adjustment device that adjusts power pressure to a regulating pressure proportional to braking pressure. An anti-skid control device according to claim 1. 5. The anti-skid control device according to claim 4, characterized in that hydraulic pressure accumulated in an accumulator is used as the power pressure. 6. The anti-skid control device according to claim 4, wherein the operating pressure of a hydraulic brake booster is used as the power pressure. 7. As the throttle valve means of the adjustment device that adjusts the power pressure to a regulating pressure proportional to the braking pressure, an open valve is used that keeps the valve open when not braking and reduces the throttle according to the braking pressure to generate high pressure when braking. An anti-skid control device according to claim 1, characterized in that: 8 As a throttle valve means of an adjustment device that adjusts the power pressure to a regulating pressure proportional to the braking pressure, it closes the communication between the hydraulic source and the actuator when not braking, connects the hydraulic source and downstream equipment, and closes the communication between the hydraulic source and the downstream equipment when braking. Using an open-closed valve that connects the hydraulic source and the downstream equipment according to the pressure, reduces the throttle to generate high pressure, and connects the hydraulic source and the actuator to supply the actuator with pressure according to the braking pressure. An anti-skid control device according to claim 1, characterized in that: 9. Anti-skid control according to claim 1, characterized in that a spring is provided as a means for supplying a constant pressure to the actuator during non-braking so as to keep the pressure generated by the throttle valve means of the regulating device constant. Device. 10. The anti-skid control device according to claim 1, characterized in that a relief valve is used as means for supplying constant pressure to the actuator during non-braking. 11 The regulating device consists of a pressure regulating valve that generates a regulating pressure proportional to the braking pressure, and a pressure reducing valve that has means for making the rate of increase in the outlet regulating pressure smaller than the rate of increase in the inlet regulating pressure when the regulating pressure exceeds the set regulating pressure. An anti-skid control device according to claim 1, characterized in that: 12. The anti-skid according to claim 11, further comprising a check valve that is arranged in parallel with the pressure reducing valve and opens only when the outlet regulating pressure of the pressure reducing valve becomes higher than the inlet regulating pressure. Control device. 13 The pressure regulating valve generates sufficient regulating pressure to open the on-off valve in the actuator, and due to the effect of the regulating pressure reduced by the pressure reducing valve, when the braking pressure exceeds the set braking pressure, the outlet braking pressure of the actuator increases. Claim 11, characterized in that the increase rate is made smaller than the increase rate of the inlet braking pressure.
Anti-skid control device as described in section. 14 Due to the effect of the regulating pressure adjusted by the pressure regulating valve, the first
When the braking pressure exceeds the set braking pressure, the rate of increase in the actuator outlet braking pressure is made smaller than the rate of increase in the inlet braking pressure, and when the braking pressure exceeds the second set braking pressure, the pressure is reduced by the pressure reducing valve. The anti-skid control device according to claim 11, characterized in that the rate of increase in the outlet braking pressure of the actuator is further reduced.