JPS5930583B2 - 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. The present invention relates to an anti-skid control device that is used as power pressure for a hydraulic actuator that reduces and controls wheel cylinder pressure to prevent skids.

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 wheel cylinder pressure, and directly supplying power pressure from a brake booster as power pressure. As is well known, however, in the former case, due to the configuration of the control valve consisting of a piston and cylinder that detect wheel cylinder pressure, the loss of fluid and residual air in the braking system increases, and the valve also has brake fluid and power oil. This has the disadvantage of complicating the structure due to the separation structure to prevent mixing of both liquids due to the action of different liquids, and in the latter case, the power pressure of the brake booster decreases due to actuator operation. The problem was that the pedal feel of the brake pedal deteriorated.

SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned drawbacks, and its gist is to install a pump in a circuit in which the pump's discharge flow is diverted at a predetermined flow rate using a flow deviter, or to A brake booster is connected to an accumulator that stores discharged pressure fluid and generates brake pressure in a master cylinder by applying power pressure generated by brake pedal operation to brake pedal depression force, and is arranged between the master cylinder and the wheel cylinder. The pump is disposed between the pump and the flow divider, or in a circuit for a surplus flow divided by the flow divider, or is connected to an accumulator other than the accumulator, and the supply of power pressure to the power chamber is interrupted. and an actuator for reducing and restoring the pressure on the wheel cylinder side when the pressure is restarted, and the actuator is operated with the power pressure as an input signal to generate a pressure corresponding to the power pressure as the power pressure. control valve means, and the first control valve means is disposed on a transmission path of the generated power pressure to the power chamber, and supplies the power pressure to the power chamber when the wheels are locked or about to lock. and a second control valve means for interrupting the operation.

An embodiment of the apparatus of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system diagram showing one embodiment of the braking system, in which the discharge flow of the pump 10 is guided to the actuator 12 via a conduit 11 and is arranged to be drainable to a reservoir 13 through a conduit 14. At the same time, it is led to a flow divider 16 through a conduit 15.

The flow divider 16 always divides a predetermined flow rate to a conduit 18 that communicates with an open center type brake booster 17, and sends the remaining flow rate through a conduit 19 to an open center type power steering device 20 that assists the steering force. .

The brake booster 17 and the power steering device 20 are connected to the reservoir 13 via conduits 21 and 22, respectively.
It leads to.

When the brake pedal 23 is depressed, the space between the conduits 18 and 21 is narrowed, thereby increasing the pressure on the conduit 18 side, and this increased pressure acts as power pressure for the booster 17, assisting the depressing force of the brake pedal 23, and increasing the cylinder pressure of the master cylinder 24. is supplied to the front brake wheel cylinders 26, 27 through a conduit 25, without increasing the pressure according to the value of the pedal depression force plus the assisting force, and then through the conduit 28. Rear brake wheel cylinder 30 via the actuator 12.
31 for normal braking operation.

In this case, the power pressure of the booster 17 is transferred to the conduit 18. It acts as an input signal pressure to the actuator 12 via the conduit 32, and a power pressure for the actuator 12 is created in response to this signal pressure, thereby maintaining communication between the conduit 28 and the conduit 29.

33.34 indicates a sensor that detects the rotational state of each rear wheel, and the output of this sensor 33.34 is sent to the computer 35.
When the computer 35 determines that the rear wheel is locked or about to lock based on this signal, it outputs a pressure reduction signal to operate the actuator 12 to reduce the pressure, cut off the communication between the conduit 28 and the conduit 29, and lock the rear wheel. So-called anti-skid control is performed in which the volume of the cylinders 30 and 31 is increased to reduce the wheel cylinder pressure, thereby avoiding a rear wheel lock condition and safely stopping the vehicle by shortening the braking distance.

Next, one embodiment of the actuator 12 will be explained with reference to FIG.

Each port 4 communicates with the conduit 11, 14, 15, 32
A first body 45 having ports 1, 42, 43, 44 and a second body 48 having ports 46, 47 communicating with the conduits 28, 29 are hermetically coupled.

Each of the ports 41, 42, 43 is provided in the first body 45.
, 44 includes an input piston 51 which is subjected to the pressure action of the port 44 and the biasing action of the spring 50 and contacts the piston 51 to connect the port 41 to the port 43 or the port 42. A stepped control piston 52 that performs communication switching is slidably disposed.

A passage 53 is provided inside the piston 52, one of which communicates with the ports 41 and 42, and the other communicates with a port 54 formed in the first body 45.

Therefore, the piston 52 receives the biasing action of the piston 51 which is the sum of the pressure of the port 44 and the biasing force of the spring 50.
9a and the land 52a and the inner wall 49b.
Due to the gap change due to the displacement of the piston 52 and the rightward movement of the piston 52, the passage 53 can communicate with the port 42, so that the pressure in the passage 53 is controlled to increase according to the pressure in the port 44.

The pressure in this passage 53 is equal to the pressure in the port 54. Conduit 55. The power is transmitted to the power chamber 58 via a solenoid valve 56, a conduit 59, and a port 57 formed in the first body 45.

A power piston 61 is slidably disposed inside the cylinder 60 forming the power chamber 58, and comes into contact with a pressure reducing piston 63 that is slidably disposed within the cylinder 62 of the second body 48. It is possible.

Further, the above-mentioned port 46 is formed in the cylinder 62, and a cut valve 64 capable of cutting off communication between the port 46 and the port 47 is disposed inside the port 46.

The cut valve 64 can come into contact with a valve seat 66 by the biasing action of a spring 65, and the right end of the pressure reducing piston 63 is arranged so as to come into contact with the cut valve 64, so that pressure is transmitted to the power chamber 58. As the power piston 61 moves to the right, the pressure reducing piston 63 also moves to the right, disengaging the cut valve 64 from the valve seat 66 against the biasing force of the spring 65, thereby establishing communication between the port 46 and the passage 67.

The port 54 is a conduit 6 branched from the conduit 55.
8 is transmitted via an orifice 69 to a port 70 and to a chamber 72 which actuates a safety valve 71 disposed in a stopper 75 secured inside the second body 48 .

The safety valve 71 is brought into contact with the valve seat 76 by the pressing action of the piston 74 under the urging force of the spring 73, and the port 46 is not communicated with the port 47 only through the passage 77.
When pressure is transmitted to the chamber 72, the right movement of the piston 78 causes the safety valve 71 to move against the biasing force of the spring 73 and close the valve seat 7.
6 and comes into contact with the valve seat 79 to cut off communication between the passage 77 and the port 47, and the port 46 is connected to the cut valve 64.
, a decompression chamber 80 whose volume increases as the decompression piston 63 moves to the left. It communicates with the port 47 via the passage 67 .

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

When the brake pedal 23 is depressed, the discharge flow from the pump 10 acts on the passage 53 through the conduit 11 → port 41 and pushes the piston 52 back to the right, causing the flow from the port 41 → the gap between the inner wall 49a and the land 52a → the port 43 → Conduit 15 → Flow divider 16 → Conduit 18 → The discharge flow flowing through conduit 18 → Brake booster 17 is throttled and the upstream pressure increases, and the brake booster 17 increases the brake pressure of the master cylinder 24 by assisting with the pedal depression force. The pressure in conduit 18 upstream of conduit 32. It acts on the piston 51 through the port 44 and pushes the piston 52 to the left.

Therefore, the gap between the inner wall 49a and the land 52a or the land 5
2a and the inner wall 49b, the passage 53
The pressure is increased in accordance with the pressure introduced into the port 44.

The pressure in this passage 53 is as follows: port 54 → conduit 55 → solenoid valve 5
6→conduit 59→port 57→power chamber 58, thereby power piston 61. As the decompression piston 63 moves to the right, the cut valve 64 also moves to the right to close the port 46 as shown in the figure.
It is in an open state where it communicates with the passage 67.

Also, the pressure in the passage 53 is transmitted to the conduit 55 → conduit 68 → orifice 69 → port 70 → chamber 72, pushing the safety valve 71 to the right, and the communication between the port 47 and the passage 77 is cut off, but the communication with the passage 67 is interrupted. Communicate.

Therefore, the brake pressure is transferred from the master cylinder 24 to the conduit to the front wheel cylinders 26 and 27 on the front wheel side, and from the master cylinder 24 to the conduit 28 on the rear wheel side.
Actuator 12 (port 46 → chamber 80 inch passage 67 →
The signal is transmitted from the safety valve 71 to the port 47) to the conduit 29 to the rear wheel cylinders 30 and 31, and a normal braking action is performed.

Next, if the wheels are locked or about to lock due to overbraking, judging from the outputs of the sensors 33 and 34, the computer 3
5 outputs the skid control signal and switches the solenoid valve 56 to cut off communication between the conduit 55 and the conduit 59, and the conduit 5
9 and the conduit 14 to drain the power chamber 58 and the power piston 61. The pressure reducing piston 63 is moved to the left to switch the cut valve 64 to the closed state to cut off communication between the master cylinder 24 and the rear wheel cylinders 33 and 34, and furthermore, the pressure of the wheel cylinders 33 and 34 acts on the chamber 80. As a result, the decompression piston 63 is displaced to the left and the chamber 8
By increasing the volume of rear wheel cylinder 3
3,340 Reduce the brake pressure.

When the rotational state of the wheel is restored due to this pressure reduction in the rear wheel cylinder, the computer 35 outputs a pressure recovery signal, causes the solenoid valve 56 to cut off communication between the conduit 59 and the conduit 68, and then disconnects the conduit 59 and the conduit 55. Power room 5 again
By transmitting the pressure in the passage 53 to 8 to carry out a normal braking operation, and then repeating this operation, the vehicle can be stopped safely without causing the wheels to skid.

The safety valve 71 is used to ensure communication between the passage 77 and the port 47 by the biasing force of the spring 73 when the pump system serving as the pressure source is missing, for example when no pressure is generated in the passage 53 or the like. Actuator 1 even if lost
2, brake operation can be maintained without communication between the master cylinder 24 and the rear wheel cylinders 33, 34.

Next, an application example of a braking system in which the configuration of the actuator 12 shown in FIG. 2 can be used as is is shown in FIGS. 3 and 4 and will be described below.

Note that the same numbers indicate the same members, and only the differences from the above-mentioned configuration will be described.

Furthermore, it is assumed that all the ports 44 of the actuator 12 are connected to the upstream side of the booster 17.

In the application example shown in FIG. 3, one conduit 93 on the downstream side of the flow divider 16 is connected to the port 41, and a conduit 94 on the upstream side of the power steering device 20 is connected to the port 43. be.

In the application example shown in FIG. 4, the flow divider 16 is not used (the discharge flow of the pump 10 is used as the power source for the booster 17 by accumulating pressure in the accumulator 100 by the unloader valve 99, and the unloader valve 99 One conduit 101 on the downstream side of the port 4
1 and is connected to the upstream side of the power steering device 20, the conduit 102 is connected to the port 43.

In the application example shown in FIG. 1 and FIGS. 3 and 4 described above, since the brake booster 17 or the power steering device 200 equipment is present downstream of the actuator 12, the pressure increase of the downstream equipment is led from the port 44 of the actuator 12. When the pressure is low compared to the pressure in the passage 53, the pressure in the actuator 120 passage 53 is increased by narrowing the gap between the inner wall 49a and the land 52a, and when it is higher than the pressure in the passage 53, the gap between the land 52a and the inner wall 49b is increased. By throttling, the pressure in the passage 53 was lowered and the pressure in the passage 53 was controlled to correspond to the power pressure of the booster 17.
, In the application example shown in FIG. 6, if there is no equipment as described above on the downstream side of the actuator 12, the actuator 120 passage is always closed by narrowing the gap between the inner wall 49a and the land 52a as shown in FIG. The configuration is such that the pressure of No. 53 is increased and controlled.

In addition, FIG. 7 shows the same members or the same numbers as FIG. 2.

An example of its application will be explained below.

In the application example shown in FIG. 5, one conduit 103 on the downstream side of the flow divider 16 is connected to the port 41,
The port 43 is a conduit 1 communicating with the reservoir.
Connect with 4.

In the application example shown in FIG. 9, one conduit 104 on the downstream side of the flow divider 16 is connected to the port 41,
The port 43 is connected to the conduit 14.

In the application example shown in FIG. 10, a conduit 105 on the downstream side of the booster 17 is connected to the port 41.
3 is connected to the conduit 14.

In the application example shown in FIG. 6, the flow of the flow divider 16 is used as a power source for the booster 17 by accumulating pressure in an accumulator 100 by operating an unloader valve 99. 106 is connected to the port 41, and the port 43 is connected to the conduit 14.

The actuator 12 in the braking system explained in each application example above was of an open center type.
The actuator 12 shown in FIG. 8 has a closed configuration, that is, the port 41 communicates with the passage 53, and by narrowing the gap between the land 52b and the inner wall 49b, the passage 53 responds to the power pressure of the booster 17. The pressure is increased to a certain level, so the port 43 described above is not necessary.

Next, an application example of a braking system using the actuator shown in FIG. 8 will be described below.

In the application example shown in FIG. 9, an unloader valve 99 is located downstream of the flow divider 16. Accumulator 108
A conduit 109 is connected to the port 41 via a check pulp 110 . It is connected to the upstream side of the booth %j7 through an accumulator 111 in sequence.

In the application example shown in FIG. 10, the unloader valve 99 is located downstream of the flow divider 16. A conduit 112 through the accumulator 100 is connected to the port 41.

As described above, the anti-skid control device of the present invention includes a pump, which is installed in a circuit that divides the discharge flow of the pump at a predetermined flow rate using a flow divider, or is connected to an accumulator that stores the discharge pressure liquid of the pump. A brake booster that generates brake pressure in a master cylinder by assisting power pressure generated by brake pedal operation with brake pedal depression force, the brake booster being disposed between the master cylinder and the wheel cylinder, and between the pump and the flow divider or the brake booster. The wheel cylinder side is arranged in a circuit for the surplus flow divided by a flow divider, or is connected to an accumulator different from the accumulator, and the supply of power pressure to the power chamber is interrupted and restarted. an actuator for reducing and restoring pressure; the actuator is operated using the power pressure as an input signal to generate a pressure corresponding to the power chamber as the power pressure; a second control valve means disposed on a transmission path of the power pressure generated by the valve means to the power chamber to interrupt the supply of the power pressure to the power chamber when the wheels are locked or about to lock; As is clear from the description of the embodiments, this system improves responsiveness and eliminates the disadvantages of brake fluid loss and increased residual air, which are the drawbacks of conventional devices.

This has excellent practical effects, such as preventing the structure from becoming complicated due to the separation of the brake fluid and power oil, and preventing deterioration of the brake pedal feeling.

[Brief explanation of drawings]

Fig. 1 is a system diagram showing an application example of a braking system in the present invention, Fig. 2 is an explanatory diagram showing an embodiment of an actuator in the present invention, and Figs. FIG. 7 is an explanatory diagram showing an application example; FIG. 7 is an explanatory diagram showing a second embodiment of the actuator in the present invention; FIG. 8 is an explanatory diagram showing a third embodiment of the actuator in the present invention; Figures 9 and 10 are explanatory diagrams showing an application example of the braking system according to the present invention. 23... Brake pedal, 17... Brake booster, 24... Master cylinder,
30, 31...Wheel cylinder (rear wheel side),
12... Actuator, 35... Computer, 52... Control valve.

Claims (1)

[Claims] 1 The device is installed in a pump and a circuit that divides the discharge flow of this pump at a predetermined flow rate using a flow divider, or is connected to an accumulator that stores the discharge pressure liquid of the pump, and is connected to the power pressure generated by brake pedal operation. A brake booster generates brake pressure in the master cylinder by assisting the brake pedal depression force, and the brake booster is disposed between the master cylinder and the wheel cylinder, and the flow is divided between the pump and the flow divider or by the flow divider. an actuator that is disposed in a surplus flow rate circuit or connected to an accumulator different from the accumulator, and that reduces and restores the wheel cylinder side pressure by interrupting and restarting the supply of power pressure to the power chamber; , the actuator operates using the power pressure as an input signal to generate a pressure corresponding to the power chamber as the power pressure.
control valve means, and the first control valve means is disposed on a transmission path of the generated power pressure to the power chamber, and supplies the power pressure to the power chamber when the wheels are locked or about to lock. and second control valve means for interrupting the anti-skid control device.