JPS5849422B2 - anti-strain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic anti-skid control device having a proportioning valve function, which stops the power pressure being supplied to the actuator when a defect occurs in the front wheel brake system due to damage or the like. By discharging the valve, the actuator's cut valve and bypass valve communicate with the mask cylinder and the rear wheel brake, eliminating the actuator's proportioning valve function and sending high pressure to the rear wheel brake, that is, the combination function. The purpose of this valve is to provide the function of a bypass valve.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram of an apparatus showing an embodiment of the present invention, showing detailed structures of an actuator 1 and a proportional pressure reduction device 2 for booster pressure.

In the figure, 3 is the brake pedal, 4 is the 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, 1o' and ii 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 39 are electric wires.

Also, 40 is a pressure reducing piston, 41 is a power piston, 42
．． 43 is a bypass valve piston, 44 is a small power piston, 45. 46 is a ball valve, 47, 48, 49
50 and 51 are the valve seats, 50 and 51 are springs, 52 is the air flow from the mask cylinder 4, 53 is the outlet to the rear wheel brake 6, and 54 and 55 are the power oil pressure inlets and outlets.

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

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

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

Next, 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 is a ball valve, γ2, γ3, 74, 75 are valve seats, and 76, γ1 spring.

78 and γ9 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 population from the pressure reducing device 2, 82 is the actuator 1
83 is the outlet to reservoir 8, said 38.39
is the wire from the computer 13.

Also, the solenoid 64. When both 65 are off, population 81 → room 84 → passage 85 → room 86 → exit 82 as shown in the drawing.
When the solenoid 64 is off and the solenoid 65 is on, the population 81 → chamber 84 → passage 85 → chamber 87 → throttle hole 8
0→passage 88→exit 82.

Also, when the solenoid 64 is on and the solenoid 65 is off, the communication goes from the outlet 82 → chamber 86 → passage 85 → chamber 89 → the outlet 83, and when both the solenoids 64 and 65 are on, the route goes from the outlet 82 →
It communicates with passage 88 → throttle hole 80 → chamber 87 → passage 85 → chamber 89 → outlet 83.

Next, Fig. 3 is a characteristic diagram showing the relationship between the mask cylinder pressure PM and the adjusted pressure PR (partly 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.

Further, in FIG. 1, reference numeral 107 is a differential valve that detects and warns pressure loss due to gap in the front or rear brake system, and is a conventionally known differential valve.

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

Also, 116 is a switching spool valve, body 117,
It is composed of spool parts 118 and 119, and the spool parts 118 and 119 are connected to the differential valve 10.
It operates in conjunction with the piston 111 of No. 7.

120 is an inlet from the pressure reducing device 2, 121 is an outlet to the actuator 1, 122 is an outlet to the reservoir 8, 123 is a lamp that warns the driver of a defect, 124 is a battery,
Reference numeral 125 is grounded and connected to the body 109 of the differential valve 107 through the vehicle body.

126, 127, 128 are electric wires, 129, 130 are brake hydraulic system piping, and 131 are power system piping.

Note that FIG. 1 shows a normal state in which neither the front brake system nor the rear brake system is damaged.

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 to the inlet of the differential valve 107. 114 → Outlet 115 → Pipe 129 → Front wheel brake 5, and the rear brake is mask cylinder 4 → Pipe 16 → Population 112 of differential valve 107 →
Outlet 113 → Pipe 130 → Inlet 52 of actuator 1 →
It is supplied in the following order: chamber 90 → chamber 100 → passage 91 → chamber 92 → outlet 53 → piping 17 → rear wheel brake 6.

On the other hand, as the pressure is increased by the hydraulic brake booster 1, the pressure also increases in the pipes 19 and 22 at the same time, and this pressure is transferred from the pipe 23 to the inlet 60 of the pressure reducing device 2 to the chamber 93 to the passage 94.
→ Chamber 95 → Outlet 62 → Piping 26 → Piping 131 → Population 120 of switching spool valve 116 → Outlet 121 → Piping 2
7. It is supplied to the chamber 96 of the actuator 1 via the pipe 28, and further supplied to the chamber 97 of the actuator 1 via the pipe 30→control valve 14→piping 31.

The booster pressure PB of this hydraulic booster 7 and M/
Let's assume the relationship with C pressure PM as PB=:=a-PM+b...
・・・・・・・・・・・・・・・・・・■, this diagram is represented by A in Figure 3, and on this diagram, the pressure increases in relation to Q-+C. do.

Moreover, when the booster pressure PB approaches P1 (at point C, that is, the cross-sectional area of the large diameter part of the piston 58 of the pressure reducing device 2 is A4,
The cross-sectional area of the small diameter part is A5, and the load of the spring 59 is 8.
2), 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 93
and 95, that is, communication between the population 60 and the exit 62 is cut off.

The booth pressure PM2P1 at this time is {P1×A5282}
It 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) +82}, the piston 58 moves to the right, edges 98 and 99 separate, and chambers 93 and 95 are communicated with each other, so that the pressure PR in chamber 95 increases and {PR. XA,>P
B X (A, A5) + 82}, the edge part 98
and 99 come into contact with each other, and the communication between chambers 93 and 95 is cut off, so the pressure of PR will not rise until edge portions 98 and 99 are separated again.

Therefore {PRXA42PBX(A4 A5)+82)
According to the relational expression, PR is reduced in pressure from PB, and actuator 1
is supplied to chambers 97 and 96.

Therefore, by substituting the above equation (2) into this equation, we get the following.

As mentioned above, when booster pressure PB becomes more than P1,
The regulated pressure PR supplied to the chamber 97 of the actuator 1 increases as indicated by the line in FIG.

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, PRxA32 (PM+A2) + S1...
...Draw the line C of the relational expression (■), let the intersection of the line entrance and the line 8 be E, and let PM at this time be Po and PR be P2.

Here, PR<P2 (including PB×P1) or PM×Po
When ((PRXA3)>(PMXA2)10st), the ball valve 45, pressure reducing piston 41, etc. of actuator 1 maintain the state shown in FIG. 1, and the ball valve 45 and valve seat 47 are separated. There is.

However, when PR>P2 or PM>PO, ((PRX
Note that A3) <(PMX'A2) + S1), the pressure reducing piston 40 and the power piston 41 move to the left, and the ball valve 45 is moved to the valve seat 47 by the spring 50.
2, the communication between the chambers 90 and 100, that is, the mask cylinder 4 and the rear wheel brake 6 is cut off.

If the pressure increases further, PR<A3 even if PM>
If A is set to 1, and the increase in force of PRxA3 is set to be much larger than the increase in force of PMxA2, the increase in force in the chamber 100 (i.e., inside the cylinder of the rear wheel brake 6)
At the hydraulic pressure PW, PM, PR, ((PRXA3)+
(PwxA1)>(PwxA2) +(PMXAI)
+81), the power piston 41 and the pressure reducing piston 40 move to the right, and the ball valve 45 is pushed up.
Since it moves away from the valve seat 47, the pressure in the chamber 90 decreases to the pressure in the chamber 10.
0 and the pressure PW in the chamber 100 rises, but PW (
(PRXA3) + (PWXAρ〈(”W1A2) +
(PM+AI) +St), the decompression 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 rise, the above-described operation is repeated, and PW is reduced in pressure with respect to PM, resulting in a relationship as shown in FIG.

In other words, it has characteristics similar to those of a proportioning valve.

The relational expression between PR, PM, and PW at this time is ((PRXA3) + (PWXA1) = (PWXA2)
10(PMxA1)+81}, and by substituting the above-mentioned equation (2) into the Kono equation, we get this relational equation, which is expressed as a two-line diagram in FIG.

In Fig. 3, PRXA3=PMXA1...
・・・・・・・・・・・・ ■Draw a E diagram and draw a F diagram (represented by the following formula) so that this intersects with point E. AH AH PR1(/)×PM+{P2− (/)×Po}...
■A3A3 From Figure 3, Figure 4, and formulas ■ to ■, as well as formula By doing so, the characteristics described above can be obtained.

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

When the brake pedal 3 that has been depressed starts to be released, the booth 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 communicated, and the oil in the chamber 95 flows through the passage 94 → the passage 101 → the chamber 102 → the outlet 63 → the pipe 33 → the check valve 10 →
Since it is discharged to the reservoir 8 via the pipe 34 → pipe 35, the chamber 9
(The check valve 10 and orifice 10' are provided so that the pressure flowing through the pipe 32 during anti-skid operation, which will be described later, does not affect the pressure reducing device 2.)

When the pressure in the chamber 95 decreases, the piston 58 returns to the right and opens the passage 1.
01 and chamber 102 are blocked, but PB, that is, chamber 93
When the pressure in chamber 95 decreases, passage 101 and chamber 102 are communicated, and the pressure in chamber 95 decreases again. By repeating this, as PB decreases, PR decreases, and of course PM also decreases, so PR
and PM decrease almost along the line in Figure 3.

Furthermore, when the pressure in PR1, that is, the chamber 97, decreases, PM also decreases, or PM>PW, so the pressure in the chamber 10 of actuator 1 decreases.
0 to the chamber 90 (PRXA3=PWXA2), and the pressure reducing piston 40 and the power piston 41 move to the left in balance, so PW decreases as PR decreases.

PR<P2 (PM<P.), that is, when PM further decreases after passing point E, PM<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 chamber 95 is opened.
Since the pressure flows into the pipe 21 and becomes approximately PB2PR, the piston 58 of the pressure reducing device 2 is returned to the right by the spring 59.

Therefore, the state shown in FIG. 1 is returned.

Next, during anti-skid braking, when the rear wheels are about to lock up due to the rear wheel brake 6 during the aforementioned braking period, 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 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.

Therefore, the pressure in the decompression chamber 100 pushes the decompression piston 40 and the power piston 41 to the left, so the ball 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 pressed against the valve seat 74, so that the passage 85 and the chamber 86 are closed. The passage 85 and the passage 88 are closed, 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 separated from the valve seat 49 by the spring 51 (and the differential pressure between PM and PW also promotes this action). Since it is crimped onto the valve seat 48, the mask cylinder 4 → pipe 16 → pipe 130 → population 52 → chamber 90 → passage 10
3→chamber 104→hole 105 of piston 42→chamber 106→outlet 53→pipe 17, communication is ensured, and braking is guaranteed.

Next, in the case of a front brake system defect, the cross-sectional area of the end 132 of the piston 111 of the differential valve 107 is A6, the cross-sectional area of the piston part 133 is A8, the cross-sectional area of the plunger part 134 is A9, and the cross-sectional area of the sleeve 110 is Let A7 be A7〉(A8 A9), (A8-A
9)> Since it is set as A6, the state shown in FIG. 1 is normally maintained.

If the front brake system is damaged here (P MX
(As-A,=0), so {PMXA6}(
7) The piston 111 moves to the left due to the force, and the spool portion 118 of the piston 111 moves to the convex portion 13 of the body 117.
5, and the spool portion 119 of the piston 111 is separated from the convex portion 136 of the body 117.

Therefore, the population 120 and the exit 121 are blocked, and the exit 121 and the exit 122 are communicated.

That is, the communication between the pressure reducing device 2 and the actuator 1 is cut off, and the actuator 1 and the reservoir 8 are communicated with each other, so that the power pressure in the chambers 97 and 96 of the actuator 1 flows out to the reservoir 8, and the power pressure in the chamber 9T flows out into the chamber 9T. The pressure inside 96 drops.

When this happens, the ball 46 separates from the valve seat 49 and is pressed to the valve seat 48, and the ball 45 is pressed to the valve seat 47, as in the case of a loss of power pressure, so that the mask cylinder 4 → the population 52 of the actuator 1 → the chamber 90→
Passage 103 → Chamber 104 → Piston 42 hole 105 → Chamber 1
06 → outlet 53 → rear wheel brake 6 is established, so the master cylinder pressure PM is directly supplied to the rear wheel brake 6.

On the other hand, the regulated pressure reduced by the pressure reducing device 2 is transferred to other equipment (
Since the supply destination to the actuator 1) is blocked by the spool portion 118 of the piston 111 in the switching spool valve 116, the chamber 95 of the pressure reducing device 2, the pipes 26, 1
Regulating pressure is supplied only within 31.25.

Therefore, the booster pressure PB does not decrease and the hydraulic brake booster 7 functions normally.

Also, the piston 111 of the differential valve 107
As the switch 108 moves to the left, the switch 108 is turned on, and the lamp 123 lights up to notify the driver of the defect.

After the defect in the front brake system is repaired, the differential valve 107 returns to the position shown in FIG. 1 due to the brake action (PMXAg-Ag)>(PMXA6)}, and the system operates normally again.

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

If the rear brake system is damaged ((P M x A7
) 10), so ((PMX(A8-A9
)) The piston 111 of the differential valve 107 moves to the right, and the lamp 123 lights up.

Also, at this time, the piston 11 of the switching spool valve 116
Since the spool part 119 of 1 is apart from the convex part 135 of the yarn day 117, the adjusted pressure reduced by the pressure reducing device 2 is supplied to the actuator 1, but an outlet for discharging it to the reservoir 8 is not provided. Therefore, there is no problem in that the adjustment pressure does not increase, and the hydraulic brake booster 7 operates normally.

Note that, in order to avoid placing an extra burden on the actuator 1 due to an increase in the adjustment pressure, a means for bringing the spool portion 119 of the switching spool valve 116 into contact with the convex portion 135 of the body 117 may be used.

Next, after the defect in the rear brake system is repaired, the brake action causes {(PMXA7)>PMX(A8-A,)}, and the differential valve 107 and switching spool valve 116 return to the state shown in FIG. , the system works normally again.

Note that the switching spool valve 116 that is linked to the differential valve 107 is connected to the pipes 131 and 27 as shown in FIG.
It is clear that the same function can be obtained even if the actuator is installed at the pipe 22 instead of between the It is clear that similar functionality can be obtained if

Although FIG. 1 shows an embodiment in which the switching spool valve 116 is mechanically interlocked with the differential valve 107, a method in which a solenoid valve or the like is operated by electrical means provided by the switch 108 may also be used.

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

As described in detail above, according to the present invention, when the front brake system is damaged, the P/V function of the actuator can be eliminated and the bypass valve function can be provided, and the braking distance of the vehicle can be shortened when the front brake system is damaged.

Furthermore, since the present invention uses a spool valve, there is no problem such as the O-ring becoming loose due to the bypass port, which is the case with conventional combination valves that use a bypass valve.

[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...Hydraulic brake booster, 8...Reservoir tank, 9, 10...
... Check valve, 13 ... Computer, 14.
... Control valve, 45.46 ... Paul valve, 100 ... First chamber, 107 ... Differential valve.

Claims (1)

[Claims] 1. A master cylinder, one or more rear wheel brakes that perform a braking 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 a pedal effort; a pressure source that supplies motive pressure from a reservoir to the hydraulic brake booster; a pressure source disposed between the mask cylinder and the rear wheel brake; an actuator that increases or decreases the braking pressure of the rear wheel brake according to the skid state of the wheels using the operating pressure of the brake booster; a control means that issues a pressure increase/decrease command signal to the actuator; an adjusting device disposed between the actuators and 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; an on-off valve that opens and closes communication between the first chamber and the mask cylinder, and closes the communication when operating pressure disappears; and when operating pressure is supplied, communicates the first chamber with the rear wheel brake. At the same time, communication between the mask cylinder and the rear wheel brake is cut off, and when the operating pressure disappears, communication between the first chamber and the rear wheel brake is cut off, and communication is made between the mask cylinder and the rear wheel brake. means for causing the rate of increase in the outlet braking pressure of the actuator to be smaller than the rate of increase in the inlet braking pressure when the actuator exceeds the set braking pressure by the action of the outlet working pressure of the regulating device; the pressure source; and the actuator, and is interlocked with the defect detection device to cut off the communication between the pressure source and the actuator, allow the actuator and the reservoir to communicate, and prevent the pressure inside the actuator from flowing. An anti-skid control device comprising means for eliminating operating pressure.