JPS6378861A - Antiskid device - Google Patents

Abstract

PURPOSE:To prevent the generation of a pedal shock in the time of antiskid action, by disconnecting a master cylinder from the other oil hydraulic operative part when the antiskid action is performed, in the case of an antiskid device for an automobile. CONSTITUTION:If a brake pedal 21 is stepped in a condition of normal running, a brake is applied by supplying pressure oil from a master cylinder 22 to a wheel brake 24. And in the time of antiskid action, a solenoid valve 23 opens introducing the pressure oil from the brake 24 into a reservoir chamber 11e, while a cut valve 11 actuates its spool 12 to be associated disconnecting a pressure of oil from the master cylinder 22 and reducing a cylinder pressure in the brake 24. During the time of this antiskid action, the cylinder pressure of the brake 24 is fine increased by opening and closing the solenoid valve 23 and actuating a pump 25. In this way, a pedal shock is prevented from its generation in the time of antiskid action, while the constitution is simplified because the oil hydraulically operated cut valve is used.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an anti-skid device for automobiles.

(Prior art) As a conventional device of this kind, the Japanese Patent Publication No. 49-28307
There is a device as described in the publication.

In this conventional anti-skid device, as shown in FIG. 5, an inlet solenoid 3 is installed between a master cylinder 1 and a wheel brake 2.

An outlet solenoid 4 was installed between the wheel brake 2 and the reservoir 3. A pump 6 was installed between the reservoir 4 and the master cylinder 1, and the circuit configuration was such that the working fluid discharged from the pump 6 circulated to the master cylinder 1 and the inlet solenoid 3.

(Problem to be Solved by the Invention) However, in the above conventional anti-skid device, the working fluid discharged from the pump 6 acts directly on the master cylinder 1, so when the anti-skid operates, a large pedal shock occurs. It had the disadvantage that it caused problems.

Furthermore, this conventional anti-skid device uses a total of two solenoids, an inlet solenoid 3 and an outlet solenoid 5, and since the solenoids are precision parts, the product cost is high and the weight is also increased. It had the disadvantage of causing

This invention was made in order to eliminate the drawbacks of the conventional anti-skid device, and is a novel anti-skid device that causes less pedal shock due to anti-skid operation, is lightweight, and reduces product cost. The purpose of this invention is to provide an anti-skid device.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a master cylinder to which a brake pedal is connected, and a brake pedal connected to the inlet side so that the brake pedal is connected to the inlet side and the outlet side when the anti-skid throat is activated. a solenoid valve whose inlet side is connected to the outlet side of the cut valve and which is switched from closed to open when the anti-skid is activated;
A reservoir is connected to the outlet side of the solenoid valve and opens and closes the force/soto valve in conjunction, a wheel brake is connected between the outlet side of the force/soto valve and the inlet side of the solenoid valve, and the inlet side is the solenoid valve. The pump is characterized in that it is equipped with a pump that is connected to the outlet side of the solenoid valve and the reservoir, and whose outlet side is connected to the inlet side of the solenoid valve and the wheel brake to supply pressurized oil from the reservoir toward the wheel brake.

(Function) In the anti-skid device according to the present invention, when the brake pedal is depressed in a normal running state, pressure oil is supplied from the master cylinder to the wheel brake to perform brake braking.

When anti-skid is activated, the solenoid valve is switched from closed to open and pressurized oil is introduced from the wheel brake into the reservoir. In conjunction with the operation of this reservoir, the cut valve cuts off the hydraulic pressure from the master cylinder, thereby reducing the cylinder pressure of the wheel brake.

During this anti-skid operation, the cylinder pressure of the wheel brake is slightly increased by opening and closing the solenoid valve and operating the pump.

When the anti-skid ends, the solenoid valve is switched from open to closed, and the pump pumps out pressurized oil from the reservoir, and in conjunction with the operation of this reservoir, the cut valve again connects the master cylinder and wheel brake. .

Restores brake braking by the master cylinder.

(Example) This invention will be described in more detail below based on an example shown in two drawings.

In FIG. 1, a spool 12 is slidably inserted into a small-diameter cylinder lla on the left side of the valve 11, and an annular communication groove 1 is formed in the center outer circumference of the spool 12.
2a is formed. The cylinder lla is formed with an inlet port flb and an outlet port 11c, which communicate with the communication groove 12a of the spool 12, and when the spool 12 is slid to the right in the figure, the inlet port 11b is connected to the communication groove 12a. Communication with the government has been cut off.

A spring 13 is interposed between the left end of the spool 12 and the cylinder wall, and biases the spool 12 in the right direction in the figure, that is, in the direction of blocking communication between the inlet port llb and the communication groove 12a. It has become. The spool 12 is allowed to slide until it engages with a stopper 15 fixed to the inner circumferential wall of the right end of the cylinder lla by a snap ring 14.

Note that the small diameter cylinder lla, the spool 12, and the spring 13 constitute a cut valve.

A piston 16 is slidably fitted inside the large-diameter cylinder lid on the right side of the valve 11 in the figure, and a snap ring 1 is attached to the piston 16 and the right end of the cylinder lid in the figure.
It is urged to slide to the left in the drawing by a spring 19 interposed between the play plate 18 fixed at 7. Note that the large-diameter cylinder 11d, the piston 16, and the spring 19 constitute a reservoir.

A protruding portion at the right end of the spool 12 in the figure is in contact with the left end surface of the piston 16 in the figure, and in an unpressurized state, the piston 1B and the spool 12 are positioned at the left end side in the figure of the cylinder lld or cylinder lla, respectively, by the spring 19. ing.

A reservoir chamber li is located between the spool 12 and the piston 16.
A port llf is connected to the reservoir chamber lie. A communication hole 12b extending in the axial direction is formed in the spool 12, and communicates the oil chamber 12c on the left side of the spool 12 with the reservoir chamber lie.

A master cylinder 22 connected to a brake pedal 21 is connected to an inlet port llb of the cylinder lla, and an input side 23a of a normally closed solenoid valve 23 is connected to an outlet port lie. And the output side 28b of the solenoid valve 23
is connected to port If' of cylinder lid,
By switching the solenoid valve 23, the outlet port lle and the port 111' are brought into communication.

Also outlet port llc and solenoid valve 23
A wheel brake 24 is connected between the input side 23a of the solenoid valve 23 and the output side 23a of the solenoid valve 23.
A pump 25 is connected to b, and this pump 25 supplies hydraulic oil to the input end 21a of the wheel brake 24 or solenoid valve 28 via a check valve 26.

Next, the operation of the above-mentioned hydraulic control circuit will be explained. 2 During normal running, the piston 16 is urged by the spring 19 and comes into contact with the left end surface of the cylinder lid as shown in the figure, and the spool 12 is also pressed by the piston IB and the spring 13 It is located at the left end position of the cylinder lla as shown in the figure. When the brake pedal 21 is depressed in this state, pressure oil is supplied from the master cylinder 22 to the wheel brake 24 via the inlet port 1lb, the continuous communication groove 12a, and the outlet port lie, and a normal brake braking force is applied.

When a sensor (not shown) detects that the wheels are likely to lock during sudden braking, the solenoid valve 23 is switched from closed to open by a signal from a control device (not shown), and pressure oil is supplied from the wheel brake 24 to the solenoid valve 2.
3-It is discharged into the reservoir chamber lie via the port 11f.

The pressure oil discharged into this reservoir chamber lie is transferred to the piston 1
Due to the difference in area between the pressure receiving surfaces of B and spool 12, piston 1
6 to the right in the drawing against the spring 19. When the piston 16 slides to the right in the drawing, the spool 12 is accordingly urged by the spring 13 and slides to the right in the drawing until it is stopped by the stopper 15.

When the spool 12 is slid to the right in the figure in this way, communication between the inlet port llb and the communication groove 12a is cut off, and the pressure oil from the master cylinder 22 is cut off. Then, the pressure oil of the wheel brake 24 is stored in the reservoir chamber l.
ie, the wheel cylinder pressure is lowered and the braking force of the brake is weakened. Note that the pressures in the reservoir chamber lie and the oil chamber 12c are balanced by the communication hole 12b, and the spool 12 is not subjected to any force in the axial direction due to this pressure.

At this time, the pump 25 is turned on, and the pressure oil is supplied to the pump 2.
5 - check valve 26 - solenoid valve 23 - pump 25 are circulated in this order.

When the slip condition is eliminated by reducing the pressure of the wheel brake 24, the solenoid valve 23 is reset by a signal from the control device, and this causes the input side 23a and the output side 2
3b is cut. Then, pressure oil is supplied to the wheel brake 24 by the pump 25, and the cylinder pressure is slightly increased.

Wheel cylinder pressure (w/
Figure 2 shows the change in pressure (e).

When the anti-skid is completed, the solenoid valve 23 returns to its original state, and the pressure oil in the reservoir chamber lie is pumped out by the pump 25, so that the piston 1B is moved against the spring 1.
The spool 12 is biased by the force 9 and slid to the left in the figure, and the spool 12 accordingly slides to the left in the figure and returns to its original position. And the inlet port llb and the communication groove 12a
The master cylinder 22 and the wheel brake 24 are communicated again, and normal braking is possible.

FIG. 3 shows another embodiment of the present invention, in which an inner cylinder 32 is fitted in a small-diameter cylinder 31a on the left side of the valve 31 in a non-slidable manner. A cut plunger 33 (spool) is slidably inserted therein.

A cut ball 34 is built in the oil chamber 32a on the left end side in the figure of the inner cylinder 32, and the oil chamber 32 is closed by a spring 35.
The valve seat 32b is biased toward the valve seat 32b formed on the right end side in the figure.

A piston 36 is slidably fitted into the large-diameter cylinder 31b on the right side of the valve 31 in the figure, and the piston 36 is urged leftward in the figure by a spring 37 as in the previous embodiment.

The left end of the cut plunger 33 in the figure is in contact with the cut ball 34, and the right end in the figure is in contact with the left end surface of the piston 36.
is the cut plunger 3 due to the biasing force of the spring 37.
3, it is pushed to the left in the figure and is separated from the valve seat 32b.

An inlet port 31c formed in the main body of the valve 31 is communicated with an oil chamber 32a of the inner cylinder 32, and this oil chamber 32a is located between an oil chamber 32c formed on the left end side of the cut plunger 33 and a valve seat 32b. This oil chamber 32e is further communicated with an outlet port 31d formed in the valve 31 body. The oil chamber 32c is formed on the right side of the annular protrusion 33b of the plunger 33 between the inner circumferential wall of the inner cylinder 32 and the outer circumferential wall of the cut plunger 33 by the communication hole 33a formed in the cut plunger 33. It is connected to He so that the pressure in both oil chambers is balanced.

A port 31f formed in the main body of the valve 31 communicates with a reservoir chamber ale formed between the piston 38 and the cylinder 31b on the left side in the drawing.

Further, this port 311' is communicated with an oil chamber 83d formed on the left side of the annular protrusion 33b of the cut plunger 33 in the drawing.

The master cylinder 22 is connected to the inlet port 31c of the valve 31 as in the previous embodiment, and the outlet port 3
The wheel brake 24 and the input side of the solenoid valve 23 are connected to 1d. A pump 25 is connected between the wheel brake 24 and the port 31f'.

In the above hydraulic circuit, when the brake pedal 21 is depressed in normal driving condition, the wheel brake is transferred from the master cylinder 22 to the wheel brake 2 via the inlet port 31c, the oil chamber 32a, the oil chamber 32cm, and the outlet port 31d.
Pressure oil is supplied to 4 to perform brake braking.

When the brake pedal 21 is depressed and the wheels are about to lock up during sudden braking, the solenoid valve 23
is switched from closed to open, and pressure oil is introduced from the wheel brake 24 into the reservoir chamber 31e via the solenoid valve 23-port 31f', causing the piston 86 to slide to the right in the figure. Along with this, cut plunger 3
3 and the cut ball 34 are urged by the spring 35 and move to the right in the figure.

The cut ball 34 is pressed against the valve seat 32b and the oil chamber 32a
The communication between the oil chamber 32e and the oil chamber 32e is cut off.

As a result, the hydraulic pressure from the master cylinder 22 is cut off, and the cylinder pressure of the wheel brake 24 is reduced. Note that the slight increase in wheel cylinder pressure during anti-skid operation is performed by the pump 25 as in the previous embodiment.

When the anti-skid is completed, the solenoid valve 23 is returned from open to closed, and the pressure oil is discharged from the reservoir chamber 31e by the pump 25, so that the piston 36 and the cut plunger 33 slide to the left in the figure, and the cut ball 34 is moved to the valve seat. By separating the oil chamber 82a from the oil chamber 32b, the oil chamber 82a and the oil chamber 32c are brought into communication again. As a result, the master cylinder 22 and the wheel brake 24 are reconnected, and normal braking is restored.

FIG. 4 is a diagram showing the circuit configuration of the first and second embodiments, where 40 represents a cut valve and 41 represents a reservoir.

In both of the above embodiments, the cut valve is operated in conjunction with the operation of the reservoir, but it is also possible to operate the cut valve by directly applying wheel cylinder pressure or pump pressure to the cut valve. be.

(Effects of the Invention) FIG. 2 is a circuit diagram showing a kid device. As described above, according to the present invention, when the anti-skid operation is performed, the master cylinder is cut off from other hydraulic operating parts, so the hydraulic pressure from the pump is transferred to the master cylinder. There is no risk of pedal shock occurring during anti-skid. In addition, a hydraulically operated cut valve is used instead of the inlet solenoid valve, and only one expensive solenoid valve is used, so the product cost can be reduced.

In order to overcome the drawbacks of the prior art, it has been considered to adopt a 3-point, 3-position solenoid valve.

This has the problem that the solenoid is relatively large and disadvantageous in terms of cost and weight. The present invention solves these problems.

[Brief explanation of the drawing]

Fig. 1 is a hydraulic circuit diagram showing one embodiment of the present invention, Fig. 2 is a diagram showing changes in wheel cylinder pressure in the same embodiment, and Fig. 3 is a hydraulic circuit diagram showing another embodiment of the invention. FIG. 4 is a circuit diagram showing the configuration of the hydraulic circuit of the present invention, and FIG. 5 is a circuit diagram showing the configuration of the hydraulic circuit of the present invention, and FIG.
id...Outlet port 11f', 81f'・
...Port lie, 31e...Reservoir chamber 12...Spool 12a...Communication groove te, ae...Piston 22...Master cylinder 23...Solenoid valve 24...Wheel brake 25...・Pump 32b...Valve seat 33...Cut plunger 84...Cut ball 40...Cut valve 41...Reservoir

Claims (4)

[Claims] (1) A master cylinder to which a brake pedal is connected,
This master cylinder is connected to the inlet side, and there is a cut valve that operates in a direction to cut off the inlet and outlet sides when anti-skid is activated, and the inlet side is connected to the outlet side of this cut valve, which switches from closed to open when anti-skid is activated. A solenoid valve, a reservoir connected to the outlet side of the solenoid valve and opening/closing the cut valve in conjunction, a wheel brake connected between the outlet side of the cut valve and the inlet side of the solenoid valve, and the inlet side connected to the reservoir. An anti-skid device comprising: a pump connected to an outlet side of a solenoid valve and a reservoir; an outlet side connected to an inlet side of the solenoid valve and a wheel brake; and a pump configured to supply pressure oil from the reservoir toward the wheel brakes. (2) A patent in which the spool of the cut valve and the piston of the reservoir are connected, and when the piston slides due to the pressure oil introduced into the reservoir, the spool slides in conjunction with this piston to cut off the pressure oil from the master cylinder. An anti-skid device according to claim (1). (3) A communication groove is formed in the spool to communicate the inlet side and the outlet side of the cut valve, and this communication groove blocks communication between the inlet side and the outlet side by sliding the spool. Anti-skid device as described in section. (4) The cut valve has a cut ball that interlocks with the spool, and the cut ball seats on the valve seat by sliding the spool and blocks communication between the inlet side and the outlet side of the cut valve. ) The anti-skid device described in section 2.