JPH0331646Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a mechanism for discharging leaked fluid used in tests of hydraulic brake devices, etc.

[Conventional technology]

For example, a leakage liquid discharge mechanism of a conventional hydraulic brake device is such that a leakage liquid discharge port is formed between a hydraulic chamber between a primary piston and a secondary piston of a tandem master cylinder and the outside of the cylinder body. There is a device that discharges liquid from the leaked liquid discharge port when testing the master cylinder or bleeding air (Japanese Patent Application Laid-Open No. 57-4448, etc.).

However, according to the prior art, since the hydraulic pressure chamber communicates with the outside air through the leakage liquid outlet, rust may occur inside due to water entering there. In this case, the rust may impede the smooth sliding of moving parts such as pistons, making it impossible for the moving parts to achieve their original functions, making it difficult to disassemble and replace parts, and causing corrosion. This may cause liquid leakage, etc. Additionally, since the hydraulic chamber is in communication with the outside air, there is a risk that the assembly fluid that adhered to the piston during the master cylinder manufacturing process will naturally flow out from the leakage fluid outlet, which could be mistaken for a malfunction. be.

[Purpose of invention]

The present invention was developed in view of the problems of the prior art described above, and aims to prevent the natural outflow of assembly fluid and rust formation in a hydraulic brake device.

[Structure of the idea]

The present invention connects two hydraulic circuits to the cylinder tube of the hydraulic brake equipment body, separates both hydraulic circuits with two sealing members built into the cylinder tube, and connects the two hydraulic circuits with two sealing members built into the cylinder tube. In a leakage liquid discharge mechanism of a hydraulic brake device in which a leakage liquid discharge port is provided between a formed cavity and the outside, the leakage liquid discharge port has an inverse structure that allows fluid to move only from the cavity to the outside. The present invention relates to a leakage fluid discharge mechanism of a hydraulic brake device characterized in that a stop valve is installed.

〔Example〕

Examples of the present invention will be described below.

FIG. 1 and subsequent figures show an embodiment in which the present invention is applied to a tandem master cylinder of a brake device. Therefore, in this embodiment, the cylinder body 1 constitutes the main body of the hydraulic brake device of the present invention. A primary piston 3 and a secondary piston 4 are slidably built into the cylinder tube 2 of the cylinder body 1, and a first hydraulic chamber 5 is formed between the pistons 3 and 4. A second hydraulic chamber 6 is formed between the piston 4 and the piston 4 . Both pistons 3 and 4 constitute the sealing member of the present invention, and the first hydraulic chamber 5 constitutes the cavity of the present invention.

Primary piston 3 has primary cup 7
and a secondary cup 8 are attached to the secondary piston 4, and a primary cup 9 and a pressure cup 10 are also attached to the secondary piston 4.

Reservoir tank mounting bases 11 and 12 are integrally formed in the upper part of the cylinder body 1, and a reservoir tank (not shown) is installed therein, and the reservoir tank is connected to the first hydraulic chamber 5 through relief ports 13 and 14. The second hydraulic pressure chamber 6 is in communication with each other.

The right end of the primary piston 3 in FIG. 1 is in contact with the tip of a push rod 16 that is moved back and forth by the brake pedal 15, so that the primary piston 3 is pushed when the brake pedal 15 is depressed.

The first hydraulic chamber 5 is a proportioning valve 17
The second hydraulic pressure chamber 6 is connected to a front brake device (not shown) via a proportioning valve 17. Both hydraulic chambers 5 and 6 are connected to the hydraulic circuit 1
Proportioning valve 17 via 8, 19
When the hydraulic pressure ratio between the first hydraulic chamber 5 and the second hydraulic chamber 6 reaches a predetermined value, the first hydraulic chamber 5
The proportioning valve 17 is operated to reduce the rate of increase in hydraulic pressure supplied from the rear brake system to the rear brake system, thereby preventing the rear wheels from locking. Such a proportioning valve 17
In this embodiment, the valve body 20 is built into a valve body 20 that is integrally formed in the lower part of the cylinder body 1.

A leakage liquid outlet 21 is formed at the bottom of the valve body 20 . The leaked liquid outlet 21 is continuous with the first hydraulic chamber 5 and the second hydraulic chamber 6, and both hydraulic chambers 5 and 6 communicate with the outside through this. A check valve 22 is installed at the leakage liquid outlet 21. The check valve 22 is a valve that only allows passage of brake fluid toward the outside from the first hydraulic chamber 5 , the second hydraulic chamber 6 , and the proportioning valve 17 . , preventing passage of fluid toward both hydraulic pressure chambers 5, 6.

The check valve 22 consists of a rubber valve body 23 shown in FIGS. 3 to 5, and a clawed washer 24 made of a metal plate shown in FIGS. 6 and 7. The valve body 23 has a rod-shaped center part 2
3a and an umbrella-shaped lip portion 23b, forming a mushroom shape as a whole. A projection 23c is provided on the upper surface of the lip portion 23b. Also, washers with claws 2
4 has a hole 24a at the center and a claw 24b on the outer periphery, and the washer 24 with claw is attached to the valve body 23 by fitting the hole 24a into the center 23a of the valve body 23.
3, and in this state, insert the valve body 23 into the leakage liquid discharge port 21 of the valve body 20, and engage the tip of the claw 24b of the claw washer 24 with the inner wall of the leakage liquid discharge port 21. is attached to the leakage liquid outlet 21. At this time, the lip portion 23b of the valve body 23 comes into elastic contact with the inner wall of the leakage liquid outlet 21.

The leaked liquid remaining inside the master cylinder and the proportioning valve 17 due to performance tests, etc., is removed by pressurizing the inside of the check valve 22.
is discharged to the outside. That is, when the inside is pressurized, the lip portion 23b of the valve body 23, which was in contact with it due to elastic force, separates from the inner wall of the leakage liquid discharge port 21 of the valve body 20, that is, the valve is opened and a passage is formed there. , through which the leakage liquid is drained.

The opening pressure of the check valve 22 may be set only by the elasticity of the lip portion 23b;
The valve opening pressure may be set by providing resistance to the elastic deformation of the lip portion 23b by bringing a claw washer 24 into elastic contact with the tip of the lip portion 3b. In this case, the elastic contact between the lip portion 23b and the claw washer 24 is as follows.
By appropriately notching the lip portion 23b,
This is done at partial positions in the circumferential direction, thereby preventing the valve opening pressure from becoming too high due to the resistance being too large. This valve opening pressure is, for example, 2 kg
f/cm ² or more is sufficient, but considering the deterioration of the elasticity of the lip portion 23b due to the influence of heat, etc., it is preferable to set it to about 5 kgf/cm ² when the valve body 23 is attached.

Further, since the leakage liquid discharge port 21 is closed by the check valve 22, water intrusion from the outside can be prevented. Note that when the infiltration pressure of water is high, the pressure acts on the inside of the lip portion 23b and expands the lip portion 23b, so that the pressing force of the lip portion 23b against the inner wall of the leakage liquid outlet 21 increases. The occlusion of the check valve 22 is reinforced to prevent water ingress.

The tips of the protrusions 23c of the valve body 23 abut against the stepped portion formed at the leakage liquid outlet 21 of the valve body 20, thereby securing a passage between the protrusions 23c. Therefore, even if the valve body 23 is pushed too far into the leaked liquid discharge port 21, a passage for the leaked liquid can be secured.

Although this embodiment is an example in which the present invention is applied to a tandem master cylinder that is integrally equipped with a proportioning valve, it may also be applied to a tandem master cylinder that is not equipped with a proportioning valve. Of course, the invention may be applied to hydraulic brake equipment other than the master cylinder.

[Effect of idea]

As explained above, according to the present invention, a check valve is installed at the leakage fluid outlet of the hydraulic brake device to allow only movement of fluid from the cavity of the hydraulic brake device to the outside. Therefore, it is possible to prevent water from entering from the outside through the leakage liquid discharge port into the cavity of the hydraulic brake device.
This prevents rust from forming inside the hydraulic brake device, ensures smooth sliding of movable parts such as pistons, facilitates disassembly and replacement of parts, and eliminates the risk of fluid leakage due to corrosion. In addition, due to the opening pressure of the check valve, the assembly fluid attached to the piston etc. during the manufacturing stage of the hydraulic brake device will not naturally flow out from the leakage fluid outlet, so it will not occur due to the above-mentioned natural flow. This also eliminates the risk of being misidentified as a malfunction.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the present invention, Fig. 2 is an enlarged view of the main part of Fig. 1, Fig. 3 is a front view of the valve body,
Figure 4 is a rear view of the valve body, and Figure 5 is the − of Figure 4.
6 is a sectional view of the washer with claws, and FIG. 7 is a front view of the washer with claws. 1... Cylinder body (hydraulic brake equipment main body), 2... Cylinder tube, 3... Primary piston (sealing member), 4... Secondary piston (sealing member), 5... First hydraulic chamber (empty space) ), 6
...Second hydraulic pressure chamber, 15...Brake pedal, 17
...proportioning valve, 18,19...
Hydraulic pressure circuit, 20... Valve body, 21... Leakage liquid outlet, 22... Check valve, 23... Valve body, 23
a... Center part, 23b... Lip part, 23c...
Protrusion, 24... washer with claw, 24a... hole,
24b...nails.

Claims (1)

[Scope of utility model registration request] 2 on the cylinder tube of the hydraulic brake equipment body.
At the same time, two hydraulic pressure circuits are connected, and both hydraulic pressure circuits are separated by two sealing members built into the cylinder tube, and leakage liquid is drained between the space formed between the two sealing members of the cylinder tube and the outside. A leakage liquid discharge mechanism of a hydraulic brake device having an outlet, characterized in that a check valve is installed at the leakage liquid discharge port to allow only movement of fluid from a cavity to the outside. leakage liquid drainage mechanism.