JPH0439106Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a vehicle hydraulic pressure system that is interposed between two master cylinders to switch the pressure fluid supplied from both master cylinders and transmit it to a brake device. Regarding brake switching valves.

[Conventional technology]

As this type of switching valve, for example,
There is a switching valve for a brake system for a training vehicle shown in Publication No. 35159.

This switching valve has a piston slidably inserted into a cylinder that has an inlet port that communicates with the main master cylinder, an inlet port that communicates with the sub-master cylinder, and one outlet port. A valve body is provided at both ends to close each inlet port, and a gap is provided between the inlet port on the main master cylinder side and the valve body blocking it, and the piston is fitted with a spring so as to close the inlet port on the sub master cylinder side. Normally, the inlet port and outlet port of the main master cylinder are connected, and when the sub master cylinder is activated, the piston is pushed by the pressure fluid of the sub master cylinder, and the sub master cylinder side is energized. The master cylinder side inlet port is opened, the main master cylinder side inlet port is closed, and the sub master cylinder side inlet port and outlet port are communicated through an orifice formed in the piston.

[The problem that the idea attempts to solve]

However, in the above structure, while the piston is pushed by the pressure fluid of the sub master cylinder and closes the inlet port on the main master cylinder side, the pressure fluid of the sub master cylinder passing through the orifice closes the inlet port on the main master cylinder side. It flows out from the port, causing a time lag in switching and a large pressure loss of the hydraulic fluid. Furthermore, if the rate of increase in liquid pressure is slow, it may be impossible to increase the pressure.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a switching valve for a hydraulic brake for a vehicle that can perform switching quickly and reliably and has little pressure loss in the hydraulic fluid.

[Means to solve the problem]

In order to achieve the above object, the present invention has a piston slidably inserted into a cylinder hole having a first inlet port communicating with a first master cylinder and a second inlet port communicating with a second master cylinder at both ends. A first liquid chamber and a second liquid chamber are defined on both sides of the piston, a first outlet port is formed in the first liquid chamber, a second outlet port is formed in the second liquid chamber, and a first valve body that closes the first inlet port when the piston moves toward the first inlet port; a first valve body that closes the first inlet port when the piston moves toward the first inlet port; The piston is characterized in that a second valve body is provided to close the second inlet port when the piston is moved, and a spring is compressed between both ends of the cylinder hole and both ends of the piston.

[Effect]

With this configuration, the first master cylinder and the first liquid chamber are always in communication with the first outlet port,
Further, the second master cylinder and the second liquid chamber are always in communication with the second outlet port.

Then, when the first master cylinder is activated,
This fluid pressure causes pressure fluid to pass through the first fluid chamber and be supplied from the first outlet port, and at the same time, the piston is pushed toward the second fluid chamber, causing the second valve body to open the second inlet port. The second liquid chamber is closed to generate liquid pressure in the second liquid chamber, and the pressurized liquid in the second liquid chamber is supplied from the second outlet port.

Furthermore, when the second master cylinder is operated, the piston is pushed toward the first liquid chamber, and the first valve body closes the first inlet port and increases the liquid pressure in the first liquid chamber. The pressurized liquid in the first liquid chamber is supplied from the first outlet port.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.

1 and 2 show a first embodiment in which a switching valve of the present invention is provided in a front wheel brake device of a motorcycle, and the switching valve 1 communicates with a front master cylinder 3 at both ends of a cylinder hole 2. A first inlet port 4 and a second inlet port 6 communicating with a rear master cylinder 5 are formed, and a piston 7 is slidably inserted into the center of the cylinder hole 2.

The piston 7 has a first cup seal 8 on its outer periphery.
and a second cup seal 9, a first liquid chamber 11 is formed between the first cup seal 8 and the first inlet port side end wall 10 of the cylinder hole 2, and a first liquid chamber 11 is formed between the second cup seal 9 and the second cup seal 9 of the cylinder hole 2. A first liquid chamber 13 is defined between the inlet port side end wall 12 and the inlet port side end wall 12, respectively.

The first liquid chamber 11 contains the first liquid of the front wheel double disc.
A first outlet port 15 that communicates with the disc brake 14 is formed in the second fluid chamber 13, and a first outlet port 17 that communicates with a second double disc brake 16 of the front wheel double disc is formed in the second fluid chamber 13, respectively.

Further, the first liquid chamber 11 has a first valve body 18 that closes the first inlet port 4, and the second liquid chamber 13 has a first valve body 18 that closes the first inlet port 4.
A valve body 19 is provided to close the second inlet port 6, respectively.

The first valve body 18 includes a valve seal 18a and a valve stem 1 extending rearward of the valve seal 18c.
8b, the valve stem 18b is inserted into the valve stem insertion hole 7a of the piston 7, and the spring retainer 20 is fixed to the end of the piston 7.
The protrusion length is regulated by the piston 7, and the piston 7 is slidably provided.

Further, the valve seal 18a of the first valve body 18 is
First inlet port side end wall 10 of cylinder hole 2
A valve spring 22 is compressed between the valve guide 21 and the valve guide 21 .

Similarly, the second valve body 19 also has a valve seal 19a.
and a valve stem 19b, the valve stem 19b is inserted into the valve stem insertion hole 7 of the piston 7.
b, and is slidably provided on the piston 7 with its protrusion length being regulated by a spring retainer 23 fixed to the end of the piston 7, and the valve seal 19a is inserted into the second inlet of the cylinder hole 2. It is supported by a valve guide 24 provided on the let port side end wall 12, and a valve spring 25 is compressed between the valve guide 24 and the valve guide 24.

Further, the piston 7 is attached to a spring retainer 20.
A return spring 26 is compressed between the spring retainer 23 and the valve guide 21, and a return spring 27 is compressed between the spring retainer 23 and the valve guide 24. Normally, the piston 7 is positioned in the center of the cylinder hole 2, and the valve A slight clearance is formed between the seal 18a and the first inlet port 4 and between the valve seal 19a and the second inlet port 6, respectively.

Next, the operation of the switching valve 1 configured as described above will be explained.

When the front master cylinder 3 is operated to generate hydraulic pressure, pressure liquid flows into the first liquid chamber 11 from the clearance between the first inlet port 4 and the valve seal 18a of the first valve body 18, and the first out From the lettuce port 15 to the front wheel side first disc brake 14
At the same time, the piston 7 is pushed toward the second fluid chamber 13 by the pressure fluid that has flowed into the first fluid chamber 11, which causes the valve spring 25 to expand and close the valve seal of the second valve body 19. The clearance between the inlet port 19a and the second inlet port 6 is immediately closed, and the fluid pressure in the second fluid chamber 13 increases, causing the second inlet port 6 to close.
Pressure fluid in the fluid chamber 13 acts on the front wheel side second disc brake 16 from the second outlet port 17,
Performs braking action on the front wheels.

Note that when the braking operation is released, the pressure fluid of the first disc brake 14 on the front wheel side flows from the first fluid chamber to the first master through the clearance between the valve seal 18a of the first valve body 18 and the first inlet port 4. The piston 7 returns to its initial position, and the valve seal 19a of the second valve body 19 is pulled back, creating a clearance between the valve seal 19a of the second valve body 19 and the second inlet port 6. is formed, the fluid pressure in the second fluid chamber 13 disappears, and the pressure fluid in the second disc brake 16 on the front wheel side flows into the second fluid chamber 1.
3, the second hydraulic chamber 13 and the second master cylinder 5 are brought into communication.

Furthermore, when the rear master cylinder 5 is operated to generate hydraulic pressure, this hydraulic pressure acts on the rear wheel side disc brake 29 which is communicated via the pressure control valve 28 and brakes the rear wheel. Acting on the second inlet port 6 of the switching valve 1, pressure fluid flows into the second fluid chamber 13 from the clearance between the second inlet port 6 and the valve seal 19a of the second valve body 19, and the pressure fluid flows into the second outlet. Port 1
At the same time, the piston 7 is pushed toward the first fluid chamber 11 by the pressure fluid flowing into the second fluid chamber 13, and the valve spring 22 is thereby expanded. , while immediately closing the clearance between the valve seal 18a of the first valve body 18 and the first inlet port 4,
The hydraulic pressure in the first liquid chamber 11 increases, and the pressurized liquid in the first liquid chamber 11 acts on the front wheel side first disc brake 14 from the first outlet port 15 to perform a braking action on the front wheel.

Therefore, compared to conventional switching valves, the switching operation can be performed more quickly and reliably, and the pressure loss of the hydraulic fluid is also extremely small.

FIG. 3 shows a second embodiment in which the switching valves of the present invention are provided in the front and rear brake devices of a motorcycle. In this embodiment, the brake hose 31 of the front master cylinder 3 is branched into two. death,
One brake hose 31a is connected to the first inlet port 4 of the front wheel switching valve 1, and the other brake hose 31b is connected to the first inlet port 4 of the rear wheel switching valve 1. The brake hose 51 is also branched into two, with one brake hose 51a connected to the second inlet port 6 of the front wheel switching valve 1, and the other brake hose 51b connected to the second inlet port of the rear wheel switching valve 1. 6 are connected to each other.

Furthermore, the first outlet port 15 of the rear wheel switching valve 1 is closed with a plug 40, and the pressure control valve 28 is connected to the second outlet port 17.
The rear wheel side disc brake 29 is connected through.

As a result, when the front master cylinder 3 is operated, the front wheel switching valve 1 operates in the same manner as in the first embodiment, and the front wheel first disc brake 14 and the front wheel second disc brake 16 perform a braking action on the front wheels. In the rear wheel switching valve 1, pressure fluid flows into the first fluid chamber 11, and the piston 7 is pushed toward the second fluid chamber 13 by the pressure fluid flowing into the first fluid chamber 11. The clearance between the valve seal 19a of the valve body 19 and the second inlet port 6 is immediately closed, and the hydraulic pressure in the second liquid chamber 13 increases, causing the second inlet port to close.
Pressure fluid in the fluid chamber 13 acts on the rear wheel disc brake 29 from the second outlet port 17 to brake the rear wheels.

Also, when operating the rear master cylinder 5,
The front wheel switching valve 1 operates in the same manner as in the first embodiment, and operates the front wheel first disc brake 14 and the front wheel second disc brake.
The disc brake 16 performs a braking action on the front wheels, and the rear wheel switching valve 1 causes pressurized fluid to flow into the second fluid chamber 13 and act on the rear wheel disc brake 29 from the second outlet port 17 to brake the rear wheels. brake.

Therefore, when either the front master cylinder 3 or the rear master cylinder 5 is operated, the front wheel switching valve 1 and the rear wheel switching valve 1 are switched and operated, respectively, so that braking action can be performed on the front wheels and the rear wheels. .

In addition, by connecting a rear wheel disc brake to the second outlet port 15 of the rear wheel switching valve 1, braking operations can be performed for the two systems of front and two systems of rear wheel braking systems. It can also be applied to brake devices for training vehicles.

[Effect of idea]

As described above, the present invention provides a switching valve for a vehicle hydraulic brake using a cylinder having at both ends a first inlet port communicating with a first master cylinder and a second inlet port communicating with a second master cylinder. A piston is slidably inserted into the hole to define a first fluid chamber and a second fluid chamber on opposite sides of the piston, respectively, a first outlet port in the first fluid chamber, and a second fluid chamber in the first fluid chamber.
A second outlet port is formed in each of the liquid chambers, and a first valve body is provided in the first liquid chamber to close the first inlet port when the piston moves toward the first inlet port. A second valve body is provided in the liquid chamber to close the second inlet port when the piston moves toward the second inlet port, and a spring is compressed between both ends of the cylinder hole and both ends of the piston. Therefore, when the first master cylinder is activated, the first liquid chamber and the first master cylinder are in communication with each other.
At the same time that pressure fluid is supplied from the first outlet port, the piston is pushed toward the second fluid chamber and the second
A liquid pressure is generated in the liquid chamber, and the second valve body immediately closes the second inlet port, and the liquid pressure in the second liquid chamber increases to supply pressurized liquid from the second outlet port.

Furthermore, when the second master cylinder operates, contrary to the above, since the second fluid chamber and the second master cylinder are in communication, pressure fluid is supplied from the second outlet port and at the same time the piston moves to the second master cylinder. The first valve body immediately closes the first inlet port by being pushed toward the first liquid chamber, and the hydraulic pressure within the first liquid chamber increases and pressurized liquid is supplied from the first outlet port.

Therefore, compared to conventional switching valves, the switching operation can be performed more quickly and reliably, and the pressure loss of the hydraulic fluid is also extremely small.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional front view of the switching valve, Fig. 2 is a brake system diagram showing a first embodiment in which the switching valve of the present invention is installed in the front wheel brake system of a motorcycle, and Fig. 3 is a front and rear wheel of the motorcycle. FIG. 3 is a brake system diagram showing a second embodiment in which wheel brake devices are each provided with a switching valve of the present invention. 1...Switching valve, 2...Cylinder hole, 3...Front master cylinder, 4...First inlet port, 5...Rear master cylinder, 6...Second inlet port, 7...Piston, 11 ...First liquid chamber, 13...Second liquid chamber, 15...First outlet port, 17...Second outlet port, 1
8...First valve body, 19...Second valve body, 26, 27
...Return spring.

Claims (1)

[Scope of utility model registration request] A piston is slidably inserted into a cylinder hole having at both ends a first inlet port that communicates with the first master cylinder and a second inlet port that communicates with the second master cylinder. defining a first liquid chamber and a second liquid chamber;
A first outlet port is formed in the liquid chamber, and a second outlet port is formed in the second liquid chamber, and when the piston moves toward the first inlet port, the first outlet port is formed in the first liquid chamber. A first valve body that closes the inlet port is provided in the second liquid chamber, and a second valve body that closes the second inlet port when the piston moves toward the second inlet port is provided in the second liquid chamber. A switching valve for a hydraulic brake for a vehicle, characterized in that a spring is compressed between both ends of the piston.