JPH0428288Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to an electromagnetic hydraulic pressure control valve that is installed in an anti-skid device of a vehicle hydraulic brake system and directly or indirectly controls the hydraulic pressure of a brake cylinder.

BACKGROUND ART A hydraulic pressure control valve of this type that combines an electromagnetic directional switching valve and an electromagnetic flow rate control valve is known, for example, from Japanese Patent Application Laid-Open No. 58-224839. The electromagnetic directional control valve is a controlled hydraulic chamber in which the internal hydraulic pressure determines the brake operating force, that is, as described in the above publication, the hydraulic pressure of the brake cylinder is operated by hydraulic pressure from another hydraulic pressure source. In an anti-skid device controlled by a regulator, a hydraulic pressure control valve is installed in the hydraulic chamber of the regulator, or in the main passage connecting the master cylinder and the brake cylinder, as described in Japanese Patent Application Laid-Open No. 142733/1983. In anti-skid devices, the hydraulic pressure chamber of the brake cylinder is selectively communicated with the master cylinder, the hydraulic pressure source such as the pump, and the low-pressure container according to the excitation and demagnetization of the first solenoid. The hydraulic pressure in the hydraulic pressure chamber is increased or decreased by allowing either the inflow of hydraulic fluid from the source into the hydraulic pressure chamber or the outflow from the hydraulic pressure chamber to the low pressure container. The electromagnetic flow control valve is provided between the electromagnetic directional control valve and the hydraulic pressure chamber of the controlled device, and includes a large diameter liquid passage and a small diameter liquid passage smaller than the large diameter liquid passage in parallel. Depending on excitation and demagnetization, there are two states: a state where the hydraulic fluid is allowed to flow in both the large diameter liquid passage and the small diameter liquid passage in parallel, and a state where the large diameter liquid passage is closed and the hydraulic fluid is allowed to flow only through the small diameter liquid passage. The flow rate of the hydraulic fluid can be switched to two levels: large and small.

In such an electromagnetic hydraulic pressure control valve, the electromagnetic flow control valve has conventionally kept the large diameter liquid passage in a closed state when the second solenoid is in a demagnetized state.

Problems to be Solved by the Invention Therefore, even during normal braking in which the anti-skid device does not operate, or even during braking in which the anti-skid device operates, before the anti-skid device starts operating, −
In the type of anti-skid device described in Japanese Patent Publication No. 224839, it is connected to the hydraulic pressure chamber of the regulator, and in the type of anti-skid device described in Japanese Patent Application Laid-open No. 142733/1983, it is connected to the hydraulic pressure chamber of the brake cylinder. In particular, in the latter case, the entire amount of hydraulic fluid supplied from the master cylinder to the brake cylinder passes through this small diameter fluid passage, which may cause a delay in brake effectiveness. . Therefore, it is necessary to provide a bypass passage that bypasses the hydraulic pressure control valve, so that the master cylinder and the brake cylinder communicate with each other when the anti-skid device is not in operation, and it is blocked when the anti-skid device is in operation. However, there was a problem in that it was disadvantageous both in terms of vehicle installation space and cost.

In addition, consideration must be given to the design, such as installing a filter to prevent foreign matter from clogging the small diameter liquid passage, but even if a filter is installed,
In the anti-skid device described in 224839, when the anti-skid device is not in operation, only hydraulic pressure is transmitted and there is almost no movement of hydraulic fluid, so there is a low possibility of clogging.
In the device described in Japanese Patent No. 142733, without a bypass valve, the entire amount of hydraulic fluid required during braking would flow through the small diameter fluid passage, which also had the problem of a high possibility of clogging.

Means for Solving the Problems The present invention was made to solve the above problems, and its gist is as follows:
The electromagnetic flow control valve maintains the large diameter liquid passage in an open state when the second solenoid is in a demagnetized state.

Operation If the electromagnetic hydraulic pressure control valve configured as described above is used in an anti-skid device, during normal braking when the anti-skid device does not operate, the hydraulic pressure source such as the master cylinder or pump can be used to control the controlled devices such as the brake cylinder or regulator. Most of the hydraulic fluid supplied to the hydraulic pressure chamber flows through the large-diameter fluid passage inside the electromagnetic flow control valve, and the second solenoid is activated only when it is necessary to gradually increase or decrease the hydraulic pressure in the hydraulic pressure chamber. When excited, the large diameter liquid passage is closed, and the entire amount of hydraulic fluid flows through the small diameter liquid passage.

Effects of the invention Therefore, when the electromagnetic hydraulic pressure control valve according to the invention is installed in the middle of the main passage connecting the master cylinder and the brake cylinder as described in the above-mentioned Japanese Patent Laid-Open No. 56-142733, In this case, most of the hydraulic fluid supplied from the master cylinder to the brake cylinder is large-diameter fluid, not only during normal control when the anti-skid device does not operate, but also during braking when the anti-skid device is activated, until the anti-skid device starts operating. As the brake passes through the passageway, delay in brake effectiveness can be effectively avoided, so that there is no need to take special measures to prevent delay in brake effectiveness.

In addition, when the electromagnetic hydraulic pressure control valve of the present invention is used in any type of anti-skid device, an effect is obtained in which the transmission of hydraulic pressure is not obstructed by the small diameter liquid passage, and furthermore, it is activated during braking. As a general rule, liquid flows through large-diameter liquid passages, especially when the liquid pressure increases gradually,
Only when gradual reduction is required, the large diameter fluid passage is closed and the fluid flows through the small diameter fluid passage, which reduces the amount of hydraulic fluid that passes through the small diameter fluid passage compared to the conventional method, so there is no foreign matter in the small diameter fluid passage. This has the effect of reducing the possibility of clogging and increasing the reliability of the electromagnetic hydraulic control valve.

Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

In FIG. 1, 10 is a housing of a hydraulic pressure control device. Although this housing is divided into members 12, 14, 16, 18, 20, 22, 24, and 25 etc. for convenience of manufacture, it functions as an integral housing 10 after assembly. The housing 10 includes a port 26 connected to a hydraulic pressure source such as a master cylinder or a pump, a port 28 connected to a controlled hydraulic pressure chamber that determines the brake operating force of a brake cylinder or regulator, and a tank. An electromagnetic directional control valve 32 is provided with a port 30 connected to a low-pressure container such as a reservoir, and selectively communicates the port 28 with the ports 26 and 30.
and an electromagnetic flow control valve 34 that switches the flow rate of the hydraulic fluid flowing in and out of the port 28 in two stages, large and small.

The electromagnetic directional switching valve 32 includes a plunger 40 to which balls 36 and 38 as valve elements are fixed at both ends. The balls 36 and 38 are opposed to valve seats 42 and 44 formed in the housing 10, respectively, and the plunger 40 is urged toward the valve seat 42 by a compression coil spring 46. Thus, while ball 36 would normally seat on valve seat 42 and close passageway 48 leading to port 30;
Ball 38 separates from valve seat 44 to open a fluid passageway 50 leading to port 26 .
The liquid passage 5 passes through the plunger chamber 52 and the communication port 54.
It is connected to 6.

The plunger 40 is held by a hollow piston 60 made of a magnetic material, and the piston 60 is fitted into a piston chamber 61 of the housing 10 so as to be slidable in the axial direction. A solenoid (first solenoid) 64 wound around a resin bobbin 62 is concentrically disposed on the outer circumferential side of the piston 60, and when this solenoid 64 is excited, the piston 60 moves as shown in FIG. is sucked downward, the plunger 40 is moved against the biasing force of the spring 46, the ball 36 is separated from the valve seat 42, and the ball 38 is seated on the valve seat 44. That is, by energizing the solenoid 64, the electromagnetic directional switching valve 32 is switched from a state in which the liquid passage 56 is communicated with the port 26 to a state in which it is communicated with the port 30.

The electromagnetic flow control valve 34 also includes a plunger 72 to which a pole 70 as a valve element is fixed, a piston 74 holding the plunger 72, and the plunger 72.
It includes a compression coil spring 78 that biases the valve away from the valve seat 76, a solenoid (second solenoid) 82 wound around a bobbin 80, and the like. The piston chamber 84 in which the piston 74 is accommodated is communicated with the liquid passage 56, while the small diameter liquid passage 8
6 and a liquid passage 88, the large diameter liquid passage 90 is further formed in parallel with the small diameter liquid passage 86 and has a larger diameter.
The large diameter liquid passage 90 is also communicated with the port 28, and a front valve seat 76 is formed at the opening of the large diameter liquid passage 90.

The ball 70 is normally kept away from the valve seat 76 by the biasing force of a spring 78.
Therefore, the hydraulic fluid flowing from the liquid passage 56 side to the liquid passage 88 side flows through the small diameter liquid passage 86 and the large diameter liquid passage 90.
However, when the solenoid 82 is energized and the piston 74 is sucked upward in FIG. In order to close the hydraulic fluid, the hydraulic fluid flows exclusively through the small diameter fluid passage 86.

FIG. 2 shows an application example of the electromagnetic hydraulic pressure control valve configured as described above. In this example, an electromagnetic directional switching valve 32 and an electromagnetic flow control valve 34, which constitute an electromagnetic hydraulic pressure control valve, are provided in a main fluid passage 104 that connects a master cylinder 100 and a brake cylinder 102. The main passage 104 is further provided with a check valve 106, and this check valve 1
A bypass passage 108 is provided to bypass the electromagnetic directional control valve 32 and the electromagnetic flow control valve 34.
10 is provided in the opposite direction to the check valve 106.

A reservoir 112 is connected to the electromagnetic directional switching valve 32 , and a pump 114 pumps up working fluid from the reservoir 112 and stores it in an accumulator 116 . That is, in this example, the master cylinder 100, the pump 114, the accumulator 116, etc. constitute the hydraulic pressure source, the hydraulic pressure chamber of the brake cylinder 102 constitutes the controlled hydraulic pressure chamber that determines the brake operating force, and the reservoir 112 This constitutes a low-pressure vessel.

The electromagnetic directional control valve 32 and the electromagnetic flow control valve 34 are normally in the state shown in FIG. Therefore, the brake fluid pressure-fed from the master cylinder 100 in response to the brake operation is supplied to the brake cylinder 102 via the check valve 106 in the main passage 104, the electromagnetic directional control valve 32, and the electromagnetic flow control valve 34. At that time, the electromagnetic flow control valve 34 moves away from the valve seat 76 as shown in FIG.
0 is in the open state, the hydraulic fluid can flow into the brake cylinder 102 at a sufficient flow rate, and a delay in brake effectiveness is effectively avoided. Furthermore, since most of the hydraulic fluid flows to the brake cylinder 102 through the large diameter fluid passage 90, and the amount of hydraulic fluid that flows through the small diameter fluid passage 86 is very small, in the unlikely event that foreign matter is mixed into the hydraulic fluid, However, the small diameter liquid passage 86
There is a very small possibility that the valve will become clogged with foreign matter, and the reliability of the electromagnetic flow control valve 34, that is, the reliability of the entire electromagnetic hydraulic pressure control valve including it, is improved.

When the hydraulic pressure of the hydraulic fluid supplied to the brake cylinder 102 is low in relation to the coefficient of friction of the road surface, the anti-skid device does not operate, and both the electromagnetic directional control valve 32 and the electromagnetic flow control valve 34 operate as shown in FIG. kept in the same state. Then, when the brake operation is released, the hydraulic fluid in the brake cylinder 102 passes through the bypass passage 108 to the master cylinder 10.
Reflux to 0.

On the other hand, if the hydraulic pressure supplied to the brake cylinder 102 is too high in relation to the coefficient of friction of the road surface, the slip rate of the wheels will increase. Detection and electromagnetic directional control valve 32
is switched to connect the brake cylinder 102 to the reservoir 112. As a result, the hydraulic fluid flows out from the brake cylinder 102 toward the reservoir 112, and the hydraulic pressure in the hydraulic pressure chamber of the brake cylinder 102 is reduced. At this time, if the controller determines that it is necessary to rapidly reduce the hydraulic pressure in the brake cylinder 102, the solenoid 82 of the electromagnetic flow control valve 34 is kept in a demagnetized state and the hydraulic fluid flows through the large diameter fluid passage 90. Reservoir 11 with sufficient flow rate
It will flow to 2. In this case, only a small amount of hydraulic fluid passes through the small diameter fluid passage 86.
Further, when the controller determines that it is necessary to gradually reduce the hydraulic pressure in the brake cylinder 102, the solenoid 82 is energized, the electromagnetic flow control valve 34 is switched, and the hydraulic fluid is transferred to the orifice passage 8.
6, the liquid is allowed to flow out into the reservoir 112 little by little.

The brake fluid that has flowed into the reservoir 112 is pumped up by the pump 114 and
It can be stored in 16. Therefore, if the hydraulic pressure in the hydraulic pressure chamber of the brake cylinder 102 is reduced as described above and the slip rate of the wheel becomes smaller than the appropriate range, the controller controls the electromagnetic directional valve 32. When the solenoid 64 is demagnetized, the high pressure hydraulic fluid stored in the accumulator 116 will flow into the brake cylinder 102. At this time, if it is necessary to rapidly increase the hydraulic pressure in the brake cylinder 102, the solenoid 82 of the electromagnetic flow control valve 34 is demagnetized, and the hydraulic fluid passes through the large diameter fluid passage 90 and reaches the brake cylinder 102 at a sufficient flow rate.
02, and conversely, if it is necessary to slowly increase the hydraulic pressure in the brake cylinder 102, the solenoid 82 is energized, the large diameter fluid passage 90 is closed, and a small amount of hydraulic fluid flows through the small diameter fluid passage 86. 102 into the brake cylinder 102.

FIG. 3 shows yet another application example of the electromagnetic hydraulic pressure control valve according to the present invention. In this example, the hydraulic pressure in the hydraulic pressure chamber of the brake cylinder 102 is increased by using the hydraulic fluid pumped up by the pump 122 from the tank 102 as a low-pressure container and supplied to other hydraulically operated devices such as the power steering device 124. This is an example of indirect control. An electromagnetic hydraulic pressure control valve consisting of an electromagnetic directional switching valve 32 and an electromagnetic flow control valve 34 is provided between the first regulator 126 and the second regulator 128.
The second regulator 1 is activated by the hydraulic fluid whose pressure is regulated by
The hydraulic pressure in the 28 power hydraulic pressure chambers 130 is controlled.

The first regulator 126 has a pressure regulating piston 1 fitted in a housing 132 in a fluid-tight and slidable manner.
34, and a power hydraulic pressure chamber 136 and a brake hydraulic pressure chamber 138 are formed on both sides of the pressure regulating piston 134. The pressure receiving surface of the pressure regulating piston 134 on the power hydraulic pressure chamber 136 side is the brake hydraulic pressure chamber 138.
The hydraulic pressure of the master cylinder 100 is guided to the brake hydraulic pressure chamber 138, so the power hydraulic pressure chamber 136 has a lower hydraulic pressure than that of the master cylinder 100, and the hydraulic pressure of the master cylinder 100 is lower than that of the master cylinder 100. In response to the increase in pressure, an increasing power hydraulic pressure will be generated. This power hydraulic pressure is guided to the power hydraulic pressure chamber 130 of the second regulator 128 via the electromagnetic hydraulic pressure control valve according to the present invention, and is also guided to the power hydraulic pressure chamber 142 of the bypass valve 140.

The master cylinder 100 is connected to the brake cylinder 102 by a main fluid passage 104 as in the application example shown in FIG.
28 are provided. Second regulator 128
The pressure regulating piston 146 is disposed in a housing 144 in a fluid-tight and slidable manner. The pressure regulating piston 146 operates by receiving the hydraulic pressure of the power hydraulic pressure chamber 130 on one pressure receiving surface and the hydraulic pressure of the brake hydraulic pressure chamber 148 on the other pressure receiving surface.
0, ball 152, compression coil spring 154
The hydraulic pressure in the brake hydraulic pressure chamber 148 is controlled based on the hydraulic pressure in the power hydraulic pressure chamber 130 by opening and closing a cut valve 156 consisting of a brake hydraulic pressure chamber 156 and increasing and decreasing the volume of the brake hydraulic pressure chamber 148.

Further, the bypass valve 140 is connected to the power hydraulic pressure chamber 14.
Piston 1 as long as power hydraulic pressure is applied to 2.
58 compresses the ball 160 with the coil spring 16
The valve is seated on the valve seat 164 against the urging force of the second regulator 128, and the hydraulic pressure controlled by the second regulator 128 is applied to the brake cylinder 102, but in the unlikely event that power hydraulic pressure is not obtained. If the ball 160 is damaged, the ball 160 is seated on the valve seat 166 by the biasing force of the spring 162, and the hydraulic fluid from the master cylinder 100 is transferred to the second regulator 12.
8 and is allowed to flow to the brake cylinder 102.

In this example, the electromagnetic hydraulic pressure control valve consisting of the electromagnetic directional switching valve 32 and the electromagnetic flow control valve 34 has a hydraulic pressure source consisting of the pump 122 and the first regulator 126, the second regulator 128, and the tank 12.
The second regulator 128 is connected to
The second regulator 128 controls the hydraulic pressure in the brake hydraulic pressure chamber 148, that is, the hydraulic pressure in the brake cylinder 102, based on the hydraulic pressure in the power hydraulic pressure chamber 130. The electromagnetic hydraulic pressure control valve according to the present invention indirectly controls the hydraulic pressure in the hydraulic pressure chamber of the brake cylinder 102. In this embodiment, the power hydraulic pressure chamber 130 is the controlled hydraulic pressure chamber that determines the brake operating force.

Also in this example, when the anti-skid device is in the non-operating state, the large-diameter liquid passage 90 is kept open, so that the hydraulic fluid enters and exits the power hydraulic pressure chamber 130 mainly through this large-diameter liquid passage.
0, and the amount of hydraulic fluid passing through the small diameter fluid passage 86 is extremely small, so even if foreign matter gets mixed into the hydraulic fluid, it will clog the small diameter fluid passage 86 and the electromagnetic flow rate control will be interrupted. The possibility of changing the control characteristics of the valve 34 is significantly reduced, and the reliability of the entire electromagnetic hydraulic pressure control valve is improved.

One embodiment of the present invention and its two typical application examples have been described above, but this is literally just an example, and the present invention can be modified in various ways based on the knowledge of those skilled in the art.
Of course, it can be implemented in an improved manner.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of an electromagnetic hydraulic pressure control valve according to an embodiment of the present invention. FIGS. 2 and 3 are system diagrams showing different application examples of the electromagnetic hydraulic control valve. 10...housing, 32...electromagnetic directional control valve, 34...electromagnetic flow control valve} electromagnetic hydraulic pressure control valve,
36, 38...Ball, 40...Plunger, 4
2, 44... Valve seat, 46... Compression coil spring, 60... Piston, 64... Solenoid (first solenoid), 70... Ball, 72... Plunger, 74... Piston, 76... Valve seat , 78
... Compression coil spring, 82 ... Solenoid (second solenoid), 86 ... Small diameter liquid passage, 90 ...
...Large diameter liquid passage, 100...Master cylinder, 10
2...Brake cylinder, 112...Reservoir,
114...pump, 120...tank, 122...
... Pump, 126 ... First regulator, 128
...Second regulator, 130...Power hydraulic chamber.

Claims (1)

[Claim for Utility Model Registration] A controlled hydraulic pressure chamber whose internal hydraulic pressure determines the brake operating force is selectively communicated with a hydraulic pressure source and a low-pressure container in accordance with the excitation and demagnetization of the first solenoid. An electromagnetic directional control valve, a large-diameter liquid passage, and a small-diameter liquid passage smaller in diameter than the large-diameter liquid passage are provided in parallel between the electromagnetic directional control valve and the hydraulic pressure chamber, and the second solenoid is excited. , an electromagnetic flow control valve that controls the flow rate of the hydraulic fluid in two stages, large and small, by opening and closing the large diameter fluid passage in response to demagnetization, and is installed in an anti-skid device of a hydraulic brake system for a vehicle, and An electromagnetic hydraulic pressure control valve that rapidly increases, rapidly decreases, gradually increases, and gradually decreases the hydraulic pressure in the hydraulic pressure chamber by changing the combination of excitation and demagnetization of the first solenoid and the second solenoid in accordance with changes in the slip rate. An electromagnetic hydraulic pressure control valve for an anti-skid device, characterized in that the flow control valve maintains the large diameter liquid passage in an open state when the second solenoid is in a demagnetized state.