JPS5849423B2 - anti-strain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an anti-skid control device having a proportioning valve function, and when a defect occurs in the front wheel brake system due to damage etc., the adjustment pressure reduced from the booster pressure is supplied to the actuator. By stopping the function of the pressure reducing device and supplying booster pressure directly to the actuator, the proportioning valve function of the actuator is eliminated and the mask cylinder and rear wheel brake are communicated, and the mask cylinder pressure is directly applied to the rear wheel brake. It is an object of the present invention to provide an anti-skid control device that provides an anti-skid control device.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an anti-skid control device.

First, the detailed structure of the actuator 1 and the proportional pressure reducing device 2 will be explained with reference to FIG. 1. 3 is a brake pedal, 4 is a mask cylinder, 5 is a front wheel brake, and 6 is a rear wheel brake.

Further, 7 is a hydraulic brake booster, 8 is a reservoir tank, 9 and 10 are check valves, 10' and 11 are orifices, 12 is a sensor, and 13 is a computer, all of the above members being known.

Reference numeral 14 designates a control valve that operates in accordance with an operation command signal from the computer 13, the detailed structure of which is shown in FIG.

15, 16, and 17 are brake fluid system piping, 18 to 35 are power hydraulic system piping, and dotted lines 36 to 35 are pipings for the power hydraulic system.
39 indicates an electric wire.

In the actuator 1, 40 is a pressure reducing piston;
1 is a power piston, 42, 43 are bypass valve pistons, 44 is a small power piston, 45, 46 are ball valves, 47, 48, 49 are valve seats, 50, 51 are springs, 52 is an inlet from the mask cylinder 4, 53
is an outlet to the rear wheel brake 6, and 54 and 55 are inlets and outlets for power hydraulic pressure.

Further, in the pressure reducing device 2, 56 is a body, and 57 is fixed to the body 56 by a plug.

A spool valve piston 58 is slidable within the body 56.

59 is a spring, 60 is an inlet from the pump 61, 62
is an outlet to the actuator 1, and 63 is an outlet to the reservoir 8.

FIG. 2 is a detailed sectional view of the control valve 14, in which 64 and 65 are solenoids, 66, 67, 68, and 69 are pistons, and 70
, 71 are pole valves, 72, 73, 74, 75 are valve seats, and 76, 77 are springs.

78 and 79 are orifices, and the orifice 79 has a small throttle hole 80 to restrict the flow of oil.

Further, the orifice 78 is used to adjust the flow rate to match the characteristics of the equipment.

81 is the inlet from the pressure reducing device 2, 82 is the actuator 1
83 is an outlet to the reservoir 8, and 38, 3 is an outlet to the reservoir 8.
9 is an electric wire from the computer 13.

Further, when both the solenoids 64 and 65 are off, the communication goes from the inlet 81 to the chamber 84 to the passage 85 to the chamber 86 to the outlet 82, and when the solenoid 64 is off and the solenoid 65 is on, the inlet 81 is connected to the chamber 84. → Passage 85 → Chamber 87 → Throttle hole 80
→ Passage 88 → Connects with exit 82.

Also, when the solenoid 64 is on and the solenoid 65 is off, the outlet 82→chamber 86-? Passage 85→passage→chamber 89→exit 83; when both solenoids 64 and 65 are on, exit 82→passage 88→throttle hole 80→chamber 87→passage 85→
Room 89 → Connects with exit 83.

Next, Fig. 3 is a characteristic diagram showing the relationship between the mask cylinder pressure PM and the adjusted pressure PR (partially booster pressure PB) after reducing the booster pressure, and Fig. 4 is a characteristic diagram showing the relationship between the mask cylinder pressure PM and the adjusted pressure PR (partially booster pressure PB). It is a characteristic line diagram showing the relationship with pressure PW.

Reference numeral 107 in FIG. 1 is a conventionally known differential valve that detects and warns of pressure loss due to a defect in the front or rear brake fluid system.

108 is a switch, 109 is a body, 110 is a piston, 111 is a sleeve, 112 is an inlet from the mask cylinder 4, 113 is an outlet connected to the rear wheel brake 6 via the actuator 1, 114 is an inlet from the mask cylinder 4, 115 is an outlet to the front wheel brake 5.

Further, the piston 110 can be protruded into the chamber 102 of the pressure reducing device 2 by actuation of the rod portion 116.

Further, 117 is a lamp that warns the driver of a defect, 118 is a battery, 119, 120, 121 are electric wires, and 122 is a ground wire that is connected to the body 109 of the differential valve 107 through the vehicle body. The switch 10 is activated by the operation of the piston 110 of 107.
8 is turned on, a lamp 117 lights up.

Further, 123 and 124 are piping for the brake hydraulic system.

Next, the effect will be explained.

First, when the brake pedal 3 is depressed during normal braking operation, the pressure in the hydraulic brake booster 7 increases and the mask cylinder 4 is pressurized, and the front brake is activated from the mask cylinder 4 to the pipe 15-p differential valve 107.
Inlet 114-P outlet 115 → pipe 123 → front wheel brake 5, and rear brake is mask cylinder 4
→Tube 16-? Inlet 1 of differential valve 107
12 → Outlet 113 → Pipe 124 → Inlet 52 of Actuake 1 → Chamber 90-F Chamber 100 → Passage 91 → Chamber 92 → Outlet 5
3 → Piping 17 → Rear wheel brake 6.

On the other hand, since the pressure is increased by the hydraulic booster 7, the pressure also increases in the pipes 19 and 22 at the same time, and this pressure is applied to the pipe 2.
3 → Inlet 60 of pressure reducing device 2 → Chamber 93 → Passage 94 → Chamber 95
→Outlet 62→Piping 26→Piping 27, and is supplied to the chamber 96 of the actuator 1, and then piping 30→Control valve 14→
It is supplied to the chamber 97 of the actuator 1 via the piping 31.

Booster pressure P of this hydraulic brake booster 7
Assuming the relationship between B and M/C pressure PM as PB-a-PM+b...
・If ■, then this diagram is represented by A in Figure 3, and on this diagram Q-? The pressure increases in relation to C.

When the booster pressure PB approaches point C, PB approaches P1 (here, the cross-sectional area of the large diameter part of the piston 58 of the pressure reducing device 2 is A, the cross-sectional area of the small diameter part is A, and the load of the spring 59 is 82). , A4> (A4 A5), the piston 58 gradually moves to the left, and finally the edge portion 98 of the body 56 and the edge portion 99 of the piston 58 come into contact, and the chamber 9
3 and 95, that is, the communication between the inlet 60 and the outlet 62 is cut off.

At this time, the booster pressure PM=P1 is { PI XA5=8
2 } is determined from the relational expression.

Furthermore, the booster pressure PB rises from P1, and the pressure PB in the chamber 93 increases.
, the pressure PR in the chamber 95 is {PRXA4<PBX(A4-A
5) +S2 }, the piston 58 moves to the right, the edges 98 and 99 separate and the chambers 93 and 95 communicate with each other, so the pressure PR in the chamber 95 increases, and { P R XA4>P
B stomach.

Therefore, according to the relational expression {PRxA4-PBx(A4-A,)+82}, PR is reduced in pressure from PB and is supplied to the chambers 97 and 96 of the actuator 1.

So, by substituting the above formula ■ into this formula, we get ? Become.

As mentioned above, when booster pressure PB becomes more than P1,
The adjustment pressure PR supplied to the chamber 97 of the actuator 1 is
It goes up like the line shown by the mouth in Figure 3.

Here, in FIG. 1, the effective pressure-receiving cross-sectional area of the seal contact portion between the ball valve 45 and the valve seat 47 of the actuator 1 is A1, the cross-sectional area of the pressure reducing piston 40 is A2, the cross-sectional area of the power piston 41 is A3, and the cross-sectional area of the spring 50 is A3. The load is 81, and in Fig. 3, PRxA3=(PM+A2)+S −・−・−・−・=
Draw line 8 of the relational expression of ■, and let the intersection of the line entrance and line 8 be E,
The PM at this time is P.

, PR is P2. Here, P R < P 2 (F
(including B < P) or PM < Po, {(PR
XA3)>(PMXA2)+S1}, the ball valve 45, pressure reducing piston 41, etc. of the actuator 1 maintain the state shown in FIG. 1, and the ball valve 45 and the valve seat 47 are separated.

However, when PR>P2 or PM>Po, {(PRX
A3)<(PMXA2)+81), the pressure reducing piston 40 and the power piston 41 move to the left, and the spring 50 causes the ball valve 45 to close to the valve seat 47.
2, the communication between the chambers 90 and 100, that is, the mask cylinder 4 and the rear wheel brake 6 is cut off.

When the pressure further increases, even if PR<PM, A3>A,
If the increase in force of PRXA2 is set to be much larger than the increase in force of PMXA1, then
At the hydraulic pressure PW, PM, PR, { (P R x
As ) + ( P W x k1) > ( P W
XA2)+(PMXA1)+St
), the power piston 41 and the pressure reducing piston 40 move to the right, and the ball valve 45 is pushed up and separated from the valve seat 47, so the pressure in the chamber 90 is introduced into the chamber 100, and the pressure PW in the chamber 100 increases. However, if PW is {(P
RXA3)+(PWXA1)<(PW+A2)+ (
PM+A, ) +S1 }, the pressure reducing piston 40 and the power piston 41 move to the left again,
A chamber 90 is formed by the ball valve 45 and the valve seat 47.
and 100 are blocked.

When PR and PM further increase, the above-described operation is repeated, and PW is reduced in pressure with respect to PM, resulting in a relationship as shown in FIG. 4.

That is, it has the same characteristics as a proportioning valve (P/V).

The relational expression between PR, PM, and PW at this time is { ( P
R x As ) + (.PWxA1) - (PWxA2)
+(PMxA1)+81}, and by substituting the formula ■into this equation, we draw a ■ line diagram, which intersects point E, and an eight-line diagram (represented by the following formula), so (KL2LN =GJ:GH}, the characteristics described above can be obtained by determining various dimensions and specifications.

Next, a description will be given of the time when normal braking is released.

When the brake pedal 3 that has been depressed begins to return, the booster pressure PB decreases and the pressure in the chamber 93 decreases, so the piston 58 of the pressure reducing device 2 moves further to the left, and the passage 10 inside the piston
1 and the chamber 102 are in communication, and the oil in the chamber 95 is transferred from the passage 94 to the passage 101 to the chamber 102-? Outlet 63 → Pipe 33 → Check valve 10
→Pipe 34→Pipe 35 to discharge to reservoir 8, so the pressure PR in chamber 95 also decreases (Check valve 10 and orifice 10 are used to prevent the pressure flowing into pipe 32 from affecting the pressure reducing device 2 during anti-skid operation, which will be described later). It was established.

When the pressure in the chamber 95 decreases, the piston 58 returns to the right and opens the passage 1.
01 and the chamber 102 are cut off, but when the pressure in PB, that is, the chamber 93, further decreases, the passage 101 and the chamber 102 are communicated with each other, and the chamber 9 is opened again.
5 decreases, and by repeating this process, PR decreases as PB decreases, and of course PM also decreases, so PR and PM decrease approximately along the line in FIG. 3.

Furthermore, when PR1, that is, the pressure in the chamber 97 decreases, PM also decreases, but since PM>PW, the pressure in the chamber 10 of the actuator 1 decreases.
0 to the chamber 90, but the pressure reducing piston 40 and the power piston 41 move leftward due to the balance of {PRxA3-PWXA2}, so PW decreases as PR decreases.

When PR<P2 (PM<P.), that is, PM decreases further after passing point E, PM becomes PW, and the liquid pressure in chamber 100 pushes the ball valve 45 and flows into the open chamber 90, so PW also decreases.

At the same time, the decompression piston 40 and the power piston 41 begin to return to the right, finally pushing up the ball valve 45,
Communication between chambers 90 and 100 is maintained.

Next, when PB<P1, that is, point C is passed, and PB further decreases, PB<PR, so the check valve 9 is pushed open and the pressure in the chamber 95 flows to the pipe 21, so that PB=PR approximately. For,
The piston 58 of the pressure reducing device 2 is returned to the right by the spring 59.

Therefore, everything is returned to the state shown in FIG.

Next, during anti-skid braking, when the rear wheels are about to lock up due to the rear wheel brake 6 in the above-mentioned braking example, the computer 13 turns on the solenoid 64.
When a signal is generated and the solenoid 64 is energized, the piston 66 is pushed to the left in FIG. is blocked, and the outlet 83 and the passage 85 communicate with each other.

That is, the pressure reducing device 2 and the chamber 97 of the actuator 1 are cut off, and the chamber 97 and the reservoir 8 are communicated with each other, so that the pressure in the chamber 97 decreases.

For this reason, the decompression chamber 100 pushes the decompression piston 40 and the power piston 41 to the left, so the pole 45
is pressed against the valve seat 47 by the spring 50,
Since the volume of the chamber 100 increases, the pressure of the chamber 100 decreases, and the braking of the rear wheel brake 6 is weakened.

Next, when the solenoid 65 is energized by a command from the computer 13, the piston 68 is pushed to the left, and the ball 71 is separated from the valve seat 75 and is pressed against the valve seat 74, thereby blocking the passage 85 and the chamber 86. As a result, the passage 85 and the passage 88 are communicated with each other, and the oil in the chamber 97 passes through the small passage 80 of the orifice 79, so that the decompression speed becomes slow.

Next, when the rear wheel is unlocked, the solenoids 64 and 65 are de-energized by a signal from the computer 13.
Since the state shown in FIG. 2 is reached, the chamber 97 is pressurized again.
The power piston 41 and the decompression piston 40 are pushed to the right, the pressure in the decompression chamber 100 is increased, and the braking of the rear wheel brake 6 is strengthened.

Next, when the solenoid 65 is energized, the oil passes through the orifice 79, which slows down the rate of pressure increase.

Repeat the above steps to perform anti-skid braking.

Next, when the power pressure decreases due to a defect in the pump 61 or the like during a power pressure deficit, the pressure reducing device 2 returns to the state shown in FIG. 1 as described above, the pressure in the chambers 97 and 96 of the actuator 1 decreases, and the The ball 45 is pressed against the valve seat 47 by the differential pressure between PM and PW (which also promotes this action), and the ball 46 is pressed against the valve seat 49 by the spring 51 (and the differential pressure between PM and PW also promotes this action). Away? The mask cylinder 4 → pipe 16 - P pipe 124 → inlet 52 → chamber 90 → passage 1
03 → Chamber 104 → Piston 42 hole 105-? Room 106
→ Outlet 53 → Communication with pipe 17 is ensured, and braking is guaranteed.

Next, when the front brake is defective, the cross-sectional area of the end 126 of the piston 110 of the differential valve 107 is A, the cross-sectional area of the piston part 127 is A8, the cross-sectional area of the plunger part is A, and the cross-sectional area of the sleeve 111 is A7. Then, since A7>(A8A9) and (A8-A9)>A6 are set, the state shown in FIG. 1 is normally maintained.

If the front brake system is defective here, (PMX(A
sA9)-0}, the piston 110 moves to the left due to the force of {PMxA6}, and its rond part 1
16 also moves to the left, forcing the piston 58 of the pressure reducing device 2 to the left.

The force relationship at this time is ((PMXA6)+S2>(PBx
It goes without saying that various dimensions should be set so that A5)) is achieved.

When this happens, the edge portion 98 of the body 56 of the pressure reducing device 2 and the edge portion 99 of the piston 58 are completely separated, and the chambers 93 and 95 are separated.
The booster pressure PB is supplied to the actuator 1 as it is.

Therefore, in FIG. 3, the relationship between the booster pressure PB and the mask cylinder pressure PM is as shown in the diagram A, and the balance relationship between PM and PB in the pressure reducing piston 40 and the power piston 41 of the actuator 1 is as shown in the diagram A. Since it is expressed graphically, it is clear that {(PBxA3)>(PnxA2)+S} is always satisfied.

Therefore, since the power piston 41 and the pressure reducing piston 40 are in the state shown in FIG. 1, the ball 45 is separated from the valve seat 47, and the mask cylinder 4-P pipe 16→differential valve 107→pipe 124-? Since communication is established between the inlet 52 of the actuator 1 → the chamber 90 → the chamber 100-p passage 91 → the u92-p outlet 53-+ the pipe 17 → the rear wheel brake 6, the mask cylinder pressure PM remains unchanged. supplied to

When the rear wheels begin to lock in this state, the pressure in the chamber 97 of the actuator 1 decreases as in the anti-skid control described above, the pressure reducing piston 40 and the power piston 41 move to the left, and the hole 45 presses against the valve seat 47. As a result, the pressure in the decompression chamber 100 decreases, so the braking force of the rear wheel brake 6 is weakened.

Thereafter, anti-skid braking can be repeated in the same way as the anti-skid braking described above.

Also, the piston 110 of the differential valve 107
At the same time as moves to the left, the switch 108 is turned on, so the ? 117 lights up to notify the driver of a defect in the brake fluid system.

After the defect in the front flake system is repaired, the brake action becomes {PMX(A8-A,)>(PMXA6)}, and the piston 11 of the differential valve 107
0 moves to the right and returns to the state shown in FIG. 1, the system returns to normal and the actuator 1 again performs the same action as a proportioning valve.

Next, the case when the rear brake system is defective will be explained.

If the rear brake system is damaged {(PMXA7) 10)
Therefore, the force of {PMX (A3-Ag)} causes the piston 1 of the differential valve 107 to
10 moves to the left and lamp 117 lights up.

Also, at this time, the piston 58 of the pressure reducing device 2 is not affected by the sides, so the pressure reducing device 2 reduces the booth pressure, and the adjusted pressure is supplied to the actuator 1, but this adjusted pressure is discharged to the reservoir 8. Since no outlet is provided,
The adjusted pressure continues to rise, and the hydraulic brake booster 7 operates normally.

After the defect in the rear brake system is repaired, the brake action causes { (PMxA7)>PMx(As A9)
} Therefore, the differential valve 107 is
The system returns to the state shown in the figure and operates normally again.

In the embodiment shown in FIG. 1, the differential valve 10
Although the piston 58 of the pressure reducing device 2 is pressed in conjunction with the pressure reducing device 2 to stop the operation of the pressure reducing device 2, other means for communicating the pipes 22 and 27 (for example, keeping the check valve 9 open) may be used. It is obvious that the same function can also be obtained by using a method in which the switch 108 of the differential valve 107 operates an electric valve or a solenoid valve.

Furthermore, it is clear that the defect detection means for the brake system is not limited to the differential valve 107, but may also be a pressure switch, a mask cylinder level warning switch, or the like.

As explained in detail above, the present invention supplies booster pressure directly to the actuator when the front flake system is damaged, so it has the same function as a conventional actuator and also prevents the rear wheel from locking when the rear brake is applied. In this case, there is an advantage that the anti-skid system can be easily controlled, and the structure can be extremely simple.

[Brief explanation of drawings]

Fig. 1 is a system diagram of an anti-skid control device showing an embodiment of the present invention, Fig. 2 is a detailed cross-sectional view of the essential parts, and Fig. 3 shows the mask cylinder pressure PM and the booster pressure after it is reduced by the deceleration device. FIG. 4 is a diagram showing the relationship between the mask cylinder pressure PM and the rear wheel brake cylinder pressure PW. Explanation of the main parts of the figure, 1...actuator,
2... Pressure reducing device, 3... Brake pedal, 4... Mask cylinder, 5... Front wheel brake, 6... Rear wheel brake. , 7... Hand truck brake booster, 8... Reservoir tank, 13...
・Computer, 14... Control valve, 45, 46
... Ball valve, 61 ... Pump,
100... Chamber, 107... Differential valve, 108... Switch, 117
······lamp.

Claims (1)

[Claims] 1. A master cylinder, one or more rear wheel brakes that perform a control action using the braking pressure from the mask cylinder, a defect detection device that detects a defect in the front wheel brake that performs a braking action using the braking pressure from the mask cylinder, and a brake pedal. a hydraulic brake booster that operates the mask cylinder in response to the pedal force of the hydraulic brake; a pressure source that supplies motive pressure from a reservoir tank to the hydraulic brake booster; a pressure source disposed between the mask cylinder and the rear wheel brake; an actuator that uses the operating pressure of the hydraulic brake booster to increase or decrease the braking pressure of the rear wheel brake according to the skid state of the wheels; a control means that issues a pressure increase/decrease command signal to the actuator; placed between
an adjusting device having means for making the rate of increase in the outlet working pressure smaller than the rate of increase in the inlet working pressure when the working pressure exceeds a set working pressure, the adjusting device being provided in the actuator and opening and closing communication between the mask cylinder and the rear wheel brake; an on-off valve that opens the communication when the working pressure of the hydraulic brake pusher is directly introduced into the actuator via means of the regulating device; and a brake set by the actuator by the action of the outlet working pressure of the regulating device. means for making the rate of increase in the outlet braking pressure of the actuator smaller than the rate of increase in the inlet braking pressure when the brake pressure exceeds the pressure; 1. An anti-skid control device comprising means for communicating with the hydraulic brake booster to directly supply the operating pressure of the hydraulic brake booster as the operating pressure of the actuator.