JPS5930584B2 - Anti skid control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention uses the power pressure of a hydraulic brake booster that assists braking force with hydraulic pressure in response to the brake pedal depression force as an input signal pressure, creates a hydraulic pressure corresponding to that pressure, and uses the hydraulic pressure to drive the wheels. O(
This article relates to an anti-skid control device.

Conventional methods of supplying power pressure to hydraulic actuators include creating and supplying power pressure by operating a control valve that controls pressure according to master cylinder pressure, and directly supplying power pressure from a brake booster as power pressure. As is well known, however, in the former case, the configuration of the control valve consisting of a piston and cylinder that detects the wheel cylinder pressure increases fluid loss and residual air in the braking system. Due to the interaction of different liquids, there is a drawback that the structure is complicated by the separation structure to prevent mixing of the two liquids.

Moreover, in the latter case, the power pressure of the brake booster decreases due to the operation of the actuator, resulting in a disadvantage that the pedal feel of the brake pedal becomes dull.

Therefore, the present invention aims to solve the above-mentioned drawbacks, and its gist is to provide a pump, a flow divider that divides the discharge flow of the pump into a first circuit with a predetermined flow rate and a second circuit with a surplus flow rate. a brake booster installed in the first circuit and configured to generate brake pressure in the master cylinder by assisting power pressure generated by brake pedal operation with brake pedal depression force, and a brake booster installed between the master cylinder and the wheel cylinder; An actuator is disposed in the second circuit and reduces and restores the pressure on the wheel cylinder side by interrupting and restarting the supply of the first pressure to the power chamber, and this actuator has the power pressure a first control valve means which operates with the power pressure as an input signal, generates a pressure corresponding to the power pressure as the power pressure, and supplies the power pressure to the power chamber; and causing the first control means to interrupt the supply of power pressure to the power chamber by interrupting the supply of power pressure to the first control valve means when the wheels are locked or about to lock. The second control valve means is provided.

An embodiment of the apparatus of the present invention will be described below based on the drawings.

FIG. 1 shows a system diagram showing one embodiment of the control system, in which the discharge flow of the pump is always controlled at a predetermined flow rate by a flow tabider 101 through a conduit 101 - an open center type brake booster 12 - an open center type power supply. It is diverted to a first circuit which returns to the reservoir 17 via the steering device 19, and the remaining surplus flow is supplied to a second circuit which returns to the reservoir 17 via the conduit 102-actuator 15-conduit 103-conduit 21.

When the brake pedal 22 is depressed, the flow from the conduit 101 to the power steering device 19 is restricted, thereby increasing the pressure on the conduit 101 side, and this increased pressure is transferred to the booster 1.
2 acts as a power pressure to assist the depression force of the brake pedal 22 and increase the cylinder pressure of the master cylinder 23 according to the value obtained by adding the assist force to the pedal depression force.
to the front brake wheel cylinders 25, 26 and to the conduit 21. Actuator 15. A rear brake wheel cylinder 29.30 VC is supplied via conduit 28 for normal braking operations.

In this case, the power pressure of the booster 12 acts as an input signal pressure to the actuator 150 via the conduit 14, and the power pressure of the actuator 15 is created according to this signal pressure to maintain communication between the conduits 27 and 28. act.

31 and 32 indicate sensors that detect the rotational state of each rear wheel, and the outputs of these sensors 31 and 32 act as inputs to a computer 33, and the computer 33 determines whether the rear wheels are locked or about to lock based on this signal. When it is determined that the situation is r/c, the actuator 15 is operated to reduce the pressure by outputting a pressure reduction signal, and the communication between the conduits 27 and 28 is cut off, and the volume on the wheel cylinder 29 and 30 side is increased to reduce the wheel cylinder pressure. To stop a vehicle safely and shorten the braking distance by performing skid control to avoid a locked state of rear wheels.

Next, one embodiment of the actuator 15 will be described with reference to FIG.

In FIG. 2, reference numeral 34 denotes a solenoid valve that controls the flow of the power pressure of the booster 12 into the actuator 15 in accordance with an input signal from the computer 33, and its configuration will be explained with reference to FIG.

The main body 35 has a large-diameter inner hole 36 that is continuous with the opening at the right end in the drawing. Medium diameter inner hole 37. A small diameter inner hole 38 is formed,
Inside the small diameter inner hole 38 are a small diameter flange 39a and a large diameter flange 39b.
A metal ring 39 having a space 39c formed on its outer periphery and a space 39c formed inside thereof is fitted and inserted with the left end surface of the large diameter flange 39b in contact with the shoulder of the medium diameter inner hole 37. There is.

Seal rings are installed between the left end surface of the small diameter flange 39a as shown in the figure and the shoulder of the small diameter inner hole 38, and between the outer peripheral surface of the large diameter flange 39b and the inner wall of the medium diameter inner hole 38. A valve seat 39d is provided at the right end of the valve body 39 in the drawing, and the cavity 39c communicates with a port 40 formed in the main body 35.

The port 40 connects to a conduit 41 which connects to the conduit 21 communicating with the reservoir 17.

42 is a conduit 46 that communicates with the actuator 15r/c.
The port 42 is connected to an annular passage 43 formed in the small-diameter inner hole 38 between the outer peripheral surface of the metal ring 39, the small-diameter flange 39a, and the large-diameter flange 39b. Communicate.

The large-diameter collar portion 39b has axial grooves 39e formed at equal intervals in the circumferential direction.

One end is bent inward in the medium-diameter inner hole 37, and the outside of the bent portion is attached to the right end surface of the large-diameter flange 39b and the seal ring mounted on the outer peripheral surface of the large-diameter flange 39b. Sleeve 4 that abuts and restricts their axial movement
4 is inserted.

A protrusion 45a of a plug 45 is fitted into the inner diameter of the right side of the sleeve 44 in a fluid-tight manner.

The plug 45 is fixed to the right end of the main body 35 by bolts (not shown), and there is a space 45b inside the protrusion 45a, and the metal ring 3 is located at the left end of the projection 45a.
A valve seat 45c facing the valve seat 39d of No. 9 is provided.

The cavity 45b is connected to a conduit 14 communicating with the booster 12.

An iron plunger 41 is disposed between the valve seat 39d of the metal ring 39 and the valve seat 45c of the plug 45.
The plunger 47 is fitted into the plunger 47 so as to be slidable in the axial direction, and detachable stainless steel valve bodies 48 and 49 are crimped onto both end surfaces of the plunger 47 and the valve seats 39d and 45c, respectively. There is.

Further, the plunger 41 has a plurality of through holes 47 in the axial direction.
a is formed.

Thus, the conduit 46 is connected to the port 42 → the annular passage 43 →
Memel ring groove 39e → plunger through hole 47a
-4- Seat 45c → Conduit 14 via inner hole 45b of plug
It is possible to communicate with

Further, the conduit 46 can communicate with the conduit 41 via the port 42 → the annular passage 43 → the groove 39e, the valve seat 39d → the cavity 39c of the metal ring → the port 40.

50 is a spring disposed between the plunger 47 and the plug 45, and the plunger 47 is always connected to the metal ring 39.
It is biased towards the side.

A solenoid coil 51 held on the outer periphery of the sleeve 44 is fitted into the large diameter inner hole 36, and the solenoid coil 51 acts on the computer 33 through a conductor 52 installed in the through hole 45d of the plug 45. connected.

When there is no input signal from the solenoid coil 51Vc computer 33, the plunger 47
The valve body 48 is pushed to the left in the drawing by an urging force of 0, and the valve body 48 is in the state shown in the drawing in which it is seated on the valve seat 39dK, and the communication between the conduit 46 and the conduit 41 is cut off.

On the other hand, when a specified current is applied to the solenoid coil 51 in response to an input signal from the computer 33, the plunger 47 is attracted to the right in the figure against the biasing force of the spring 50, and the valve body 49 is seated on the valve seat 45c. I am forced to do it.

Thus, the conduit 46 is cut off from communication with the conduit 14 and communicated with the conduit 41.

Next, the actuator 15 will be explained with reference to FIG. 2. Each port 5 communicating with the conduit 46, 21, 13, and
A first body 59 having 5, 56, 57, 58 and a second body 62 having respective ports 60, 61 communicating with said conduits 27, 28 are connected.

Each of the ports 55, 56, 57 in the first body 59
．． Inside the stepped cylinder 63 which can communicate with the port 58 is an input piston 65 which receives the pressure action of the port 55 and the biasing action of the spring 64, and an input piston 65 which is in contact with the piston 65 and which is in contact with the port 57.
A stepped control piston 66 for switching communication between the port 56 and the port 58 is slidably disposed.

Inside the piston 66, one side can communicate with the ports 56 and 57, and the other side can communicate with the first body 5.
A passage 68 is provided which communicates with the port 67 bored in the hole 9.

Therefore, as the piston 66 receives the biasing action of the piston 65 which is the sum of the pressure of the port 55 and the biasing force of the spring 64, the land 66a of the piston 66 and the cylinder 63
The pressure in the passage 68 is controlled to increase in accordance with the pressure in the port 55 by the narrowing action of the gap between the inner wall 63a and the inner wall 63a.

The pressure in this passage 68 is determined by the pressure in the port 67, the conduit 69, the
Power chamber 71 via port 70 bored in body 59
transmitted to.

A power piston 73 is slidably disposed inside the cylinder 72 forming the power chamber 11, and can come into contact with a decompression piston 75 slidably disposed within the cylinder 74 of the second body 62. It is.

Further, the aforementioned port 60 is formed in the cylinder 74, and a plug 77 is provided at the left end of the second body 62 in the figure, and a cut valve 76 that can cut off communication between the port 60 and the port 61 is disposed inside the plug 77. Liquid-tightly screwed on.

The cut valve 16 is pressed against the valve seat 1 by the biasing action of the spring 78.
9, and the left end of the pressure reducing piston 75 is arranged so as to be able to touch the cut valve 76. When pressure is transmitted to the power chamber 71, the pressure reducing piston 75 also moves as the power piston 73 moves to the left. The cut valve 16 is moved to the left and removed from the valve seat 79 against the biasing force of the spring T8, thereby communicating the port 60 and the passage 80.

The power pressure of the booster 12 is transferred from the conduit 14 through a branched conduit 81 to a port 82 and then to the second body 6.
2 is transmitted to a chamber 85 which operates a safety valve 84 disposed in a stopper 83 secured inside the chamber 85.

The safety valve 84 is brought into contact with the valve seat 87vc by the suppressing action of the piston 86 which is receiving the urging force of the spring 85, so that the port 60 does not communicate with the port 61 only through the passage 88.
When pressure is transmitted to the character 85, the piston 89 moves to the left, causing the safety valve 84 to move against the biasing force of the spring 85 to the valve seat 8.
7 and comes into contact with the valve seat 90 to cut off communication between the passage 88 and the port 61, and the port 60 is connected to the cut valve 76.
, a decompression chamber 91 whose volume increases as the decompression piston 75 moves to the right. It communicates with the port 61 via the passage 80.

Next, the operation of the device of the present invention will be explained.

When the brake pedal 22 is not depressed, the discharge direction of the pump 10 is from the conduit 101 to the brake booster 12.
-4 Pipe 13 → Introduced into cylinder 63 via port 5γ, suppresses piston 66 to the left in the figure, and spring 64
The pistons 65 and 66 are held in a position balanced with the biasing force of the pistons 65 and 66.

When the brake pedal 22 is depressed, the discharge flow flowing from the pump 10 to the conduit 101 to the booster 12 is throttled, the upstream pressure of the booster 12 increases, and the brake booster 12 adds the brake pressure of the master cylinder 23 to the pedal depression force. The increased pressure on the upstream side of the booster 12 is transmitted through the conduit 14 to the inner hole 45 of the plug of the solenoid valve 34.
transmitted to b.

The plunger 47 of the solenoid valve 34 is pushed to the left in the figure by the biasing force of the spring 50, and the valve body 48 is pushed toward the valve seat 39 d.
K is seated in the illustrated position, so the inner hole 45b
The pressure transmitted to the valve seat 45c → the inner hole 47a of the plunger 47 → the groove 39e of the Memel ring 39 → the annular passage 43
→ Port 42 → Conduit 46 → Acts on piston 65 via port 55 of actuator 15.

The pressure in the port 55 moves the piston 65 to the right in the figure,
Then, the piston 66 is moved to the right.

Therefore, by narrowing the gap between the land 66a of the piston 66 and the inner wall 63a of the cylinder 63, the pressure in the passage 68 is increased in accordance with the pressure introduced to the port 55.

The pressure in this passage 68 is from port 61 to conduit 69 to port 7.
0→Power piston 73. is transmitted to the power chamber 71. As the pressure reducing piston γ5 moves to the left, the cut valve 76 also moves to the left as shown in the figure, and enters a closed state where the port 60 and the passage 80 are communicated with each other.

Also, the pressure in the conduit 14 is transmitted from the conduit 81 to the port 82 to the chamber 85, pushing the safety valve 84 to the left via the piston 89, and communication with the port 61H passage 88 is cut off, but the passage 8
It communicates with 0.

Therefore, the brake pressure on the front wheel side is from master cylinder 23 → conduit 24 → front wheel cylinder 25.26.
On the rear wheel side, the power is transmitted from the master cylinder 23 to the actuator 15 (port 60 to chamber 91 to passage 80 to safety valve 84 to port 61) to conduit 28 to rear wheel cylinder 29.30, and normal braking is performed. .

Next, the operation of the device of the present invention when the wheels are locked or about to lock due to overbraking will be explained.
Judging from the output of the computer 32, if the wheels are locked or about to lock due to over-braking, the computer 33 will activate the skin.
1ilJ control signal is output to the solenoid valve 34 via the signal conductor 52.
energizes the seventh solenoid 51.

Due to the excitation of the solenoid coil 51, the plunger 41 moves to the right in the figure against the urging force of the spring 50, and the valve body 4
On the other hand, the valve body 49 is removed from the valve seat 39d and is seated on the valve seat 45cK.

Therefore, the port 42 is disconnected from the conduit 14 and communicated with the conduit 41, and the pressure at the port 55 is changed from the conduit 46 to the solenoid valve 3.
4 (port 42 → annular passage 43 → groove 39e → valve seat 39d
→ Memel ring inner hole 39c → port 40) → conduit 41
→ Conduit 21 → Transmitted to reservoir 17.

Therefore, the piston 66 moves to the left against the biasing force of the spring 64, and moves the power chamber 11 from port 10 to conduit 69 to port 61 to passage 68 to port 56 to conduit 21 to reservoir 17.
Power piston without head drain 73. Decompression piston 7
5 to the right to switch the cut valve 76 to the closed state, thereby blocking communication between the port 60 and the passage 80.

On the other hand, the pressure in the conduit 14 is determined by the conduit 81 branched from the conduit 14.
→ Port 82 → Since it is transmitted to chamber 85, safety valve 8
4 is pushed to the left and seats on the valve seat 90, blocking communication between the passage 88 and the port 61.

Therefore, the communication between the master cylinder 23 and the rear wheel cylinders 29 and 30 is cut off, and the pressure of the wheel cylinders 29 and 30 acts on the chamber 91, so that the decompression piston 15 is displaced to the right and the volume of the chamber 91 is reduced. is increased, and the brake pressure in the rear wheel cylinders 29,30 is reduced.

When the rotational state of the wheel is restored by reducing the pressure in the rear wheel cylinders 29 and 30, the computer 33 outputs a pressure recovery signal to de-energize the solenoid coil 51 of the solenoid valve 34, and the plunger 47 is activated by the biasing force of the spring 50. Press to the left to cut off the communication between the conduit 46 and the conduit 41, disconnect the conduit 46 from the conduit 14, and transmit the pressure in the passage 68 to the power chamber T1 again to perform the normal braking operation, and repeat this operation thereafter. As a result, the vehicle can be safely stopped without skidding on the wheels.

The safety valve 84 secures communication between the passage 88 and the port 61 by the biasing force of the spring 85 when the pump system that is the pressure source is damaged (1), for example, when no pressure is generated in the passage 68 etc. Regardless of the operation of the actuator 15, brake operation can be maintained without communication between the master cylinder 23 and the rear wheel cylinders 29 and 30.

As explained above, according to the present invention, the flow divider divides the output flow of the pump q into a constant flow rate flowing to the brake booster side and a surplus flow rate flowing to the actuator side, thereby increasing the power pressure of the brake booster when the brake is applied. The power of the actuator is controlled by a solenoid valve according to the rotational state of the wheels, and the controlled power pressure is used as an input signal and the control valve operates according to the pressure to reduce brake pressure and pressurize it to activate anti-skid control. By creating pressure, the power pressure is switched using a solenoid valve, so it requires only a small amount of oil, can be made smaller, and has improved responsiveness.

Moreover, it has practical advantages such as being able to prevent the disadvantages of conventional devices such as loss of brake fluid, increase in residual air, complication of structure due to separation of brake fluid and power oil, and deterioration of brake pedal feeling. be effective.

[Brief explanation of drawings]

Figure 1 is a system diagram showing an example of application of the braking system in the present invention, Figure 2 is an explanatory diagram showing an example of the actuator in the present invention, and Figure 3 is an enlarged view of the solenoid valve in Figure 2. FIG. 10... Pump, 12... Brake booster, 15... Actuator, 17...
... Reservoir 19 ... Power steering device, 22 ... Brake pedal, 23 ...
・Master cylinder, 29° 30...Rear wheel cylinder, 31, 32...Sensor, 33
...compu, J, 34...W valve.

Claims (1)

[Claims] 1. A pump, a flow divider that divides the discharge flow of the pump into a first circuit with a predetermined flow rate and a second circuit with a surplus flow rate;
A brake booster is installed in the first circuit and generates brake pressure in the master cylinder by assisting the power pressure generated by brake pedal operation with the brake pedal depression force, and the brake booster is arranged between the master cylinder and the wheel cylinder. and an actuator that is disposed in the second circuit and that reduces and restores the pressure on the wheel cylinder side by interrupting and restarting the supply of power pressure to the power chamber, and this actuator reduces and restores the pressure on the wheel cylinder side. a first m1m valve means which operates with the input signal as an input signal to generate a pressure corresponding to the power pressure as the power pressure and supply it to the power chamber; and a first control valve means on the transmission path of the power pressure to the first control valve means. interrupting the supply of power pressure to the first control valve means when the wheels are locked or about to lock, thereby causing the first control valve means to interrupt the supply of power pressure to the power chamber; An anti-skid control device characterized in that it is provided with second control valve means for controlling.