JPS594843Y2 - Master cylinder reservoir device - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a master cylinder reservoir device.

The reservoir device of the vehicle brake master cylinder is
As the brake fluid level in the reservoir decreases, it is necessary to introduce outside air into the reservoir to keep the pressure inside the reservoir equal to that of the outside air at all times. It is necessary to prevent brake fluid from leaking out of the reservoir in the event of splashing.

Additionally, if foreign matter gets mixed into the brake fluid and enters the master cylinder, it can cause problems such as damage to the cup seal or piston, so it is necessary to filter out the foreign matter mixed in the brake fluid. becomes.

From this point of view, conventionally, a reservoir cap that has a cavity inside and is attached to the brake fluid injection opening of the reservoir body, and a reservoir cap that is provided on the lower surface of this reservoir cap and that communicates the inside of the reservoir with the outside air through the cavity. A ventilation hole that communicates with the ventilation hole, a shielding plate that is arranged close to and opposite to the bottom of the ventilation hole and that prevents brake fluid from entering the ventilation hole, and a filter that engages with the reservoir body and is arranged inside the reservoir. Master cylinder reservoir devices came into use.

However, in such a reservoir device, since the shielding plate and the filter are individually provided, the number of parts constituting the reservoir device increases.

In addition, a structure for individually attaching them to the reservoir cap or the reservoir body is required, resulting in various disadvantages such as the structure of the reservoir device being complicated and the work for such attachment becoming complicated.

The present invention has been made in view of the above-mentioned drawbacks, and aims to provide a reservoir device for a master cylinder that satisfies the above-mentioned requirements with a simple structure and a small number of parts. It is formed from a plate-shaped portion that is integrally provided to the filter unit and faces the ventilation hole via a portion that extends toward the ventilation hole of the filter unit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to drawings.

In the figure, 1.1 is a reservoir main body, the inside of which is divided into chambers 4 and 5 by a partition wall 3 having a liquid communication port 2, and chamber 4 is one of the hydraulic pressure generating chambers of the master cylinder via a lower outlet 6. (not shown), and the chamber 5 is connected to the other hydraulic pressure generating chamber (not shown) by an outlet lower.

Reference numeral 8 denotes a brake fluid injection opening for injecting brake fluid provided at the upper part of the chamber 4, and has a stepped portion 9 projecting inward at its lower end.

Reference numeral 10 is an integrated cup-shaped filter that opens upward and has a flange portion 11 on its outer periphery that engages with the stepped portion 9 of the brake fluid injection opening 8, and the central portion thereof bulges upward. A shielding plate 13 is formed which is flat and closely faces a ventilation hole 24 of a membrane plate member 16, which will be described later.

A filter portion 12 is provided in an annular shape between the shielding plate 13 and the flange portion 11 to filter out foreign substances mixed in the brake fluid.

Reference numeral 14 denotes a reservoir cap, which is composed of a cap body 15 and a membrane plate member 16. The cap body 15 has an inner space 17 that opens downward, and an annular recess 18 on the outer periphery, both of which are connected to a passage 19. It's more connected.

20 is a protrusion 2 provided at the upper end of the brake fluid injection opening.
1 and prevents the reservoir cap from falling off.

The membrane plate member 16 is attached to an annular groove 23 provided in the cap body 15 by its outer circumferential seal portion 22, and is provided with a ventilation hole 24 in the center that communicates the inside of the reservoir body 1 and the cavity 17.

Note that the seal portion 22 has a cup shape that opens downward, and when the pressure inside the reservoir body 1 decreases compared to the recess 1B, the outer lip deforms and the reservoir body 1 is removed from the recess 18.
Allows air to flow inside.

Reference numeral 25 denotes a liquid level detector of a normal structure placed in the chamber 5, which includes a switch body 26 having a reed switch (not shown) inside, and a float 2 containing a permanent magnet.
7, and a signal for creating a reed switch is sent through a lead wire 28.

Next, the effect will be explained.

When the brake fluid level in the reservoir body 1 decreases due to wear of the lining of the brake device installed on the vehicle's wheels, outside air flows between the lower surface 15a of the flange of the cap body 15 and the upper surface of the brake fluid injection opening 8. Since it flows into the reservoir body 1 through gaps caused by surface roughness, recesses 18, passages 19, cavities 17, and ventilation holes 24, the pressure inside the reservoir body is maintained at the same pressure as the atmosphere.

When the brake fluid level is suddenly changed due to rapid acceleration/deceleration when the vehicle starts or stops or due to vibration of the vehicle body, the brake fluid splashes onto the lower surface of the membrane plate member 16. However, since the shielding plate 13 of the filter unit 10 is arranged at a distance of, for example, 2 to 3 mm from the membrane plate at the vent hole 24, the brake fluid reaches the vent hole 24 and flows into the cavity 17. In addition, when the amount of splashed brake fluid is large and there is a risk that the brake fluid will flow into the space 17 from the vent hole 24, the filter unit 10 will be pushed upward by the splashed brake fluid and the shielding plate 18 will be pushed up. will block the ventilation hole, so the brake fluid will leak into the air space 1.
7 is completely prevented.

Furthermore, even if brake fluid flows into the cavity 17, it will not immediately leak out of the reservoir, and furthermore, the brake fluid will not leak out of the reservoir immediately.
through the recess 18 and then into the cap body 1
It must pass through the gap between the lower surface 15a of the collar 5 and the upper end surface of the brake fluid injection opening 8.

Furthermore, since the seal portion 22 of the membrane plate member 16 has a cup shape that opens downward, even if brake fluid enters the recess 1B, the pressure inside the reservoir body 1 will drop rapidly when the brake is depressed twice. Then, the outer lip deforms and acts to return the brake fluid in the recess 18 into the reservoir body 1.

As described above, outside air is guided into the reservoir body 1, and brake fluid is prevented from leaking to the outside of the reservoir body 1.

Note that when the brake fluid is replenished from the brake fluid injection opening 8, the brake fluid passes through the filter section 12, so that foreign matter mixed on the brake fluid is removed by the filter section 12, and the brake fluid is removed from the lower part of the chamber 4 or 5. will not invade.

In addition, since the filter part 12 of the filter unit 10 is formed deeply downward, when the filter unit 10 moves upward as described above, foreign matter accumulated in the filter part 12 is disposed between the step part 9 and the flange. It does not pass between the part 11 and enter the lower part of the chamber 4.

In addition, by engaging the flange portion of the filter unit 10 with the stepped portion 9 and attaching the filter unit 10 to the reservoir body 1, the shielding plate 13 is placed at a predetermined position close to and facing the ventilation hole 24. There is no need to specially form a structure for attaching the shielding plate, and the complicated work of individually assembling the integrated filter and the shielding plate to the reservoir device as in the conventional art can be eliminated.

As is clear from the above description, the present invention has the advantage that the shielding plate is formed from a plate-shaped portion that is integrally provided to the filter and faces the ventilation hole through a portion that extends toward the ventilation hole of the filter. This not only allows outside air to be guided freely into the reservoir and prevents brake fluid from leaking out of the reservoir, but also reduces the number of parts that make up the reservoir device, simplifies its structure, and improves productivity. Since the shielding plate is assembled to the reservoir body at the same time as the filter, it has remarkable effects such as improved workability.

Note that the shape of the integrated filter is not limited to the embodiment, and it is sufficient that a shielding plate is formed opposite to the ventilation hole on the lower surface of the reservoir cap.

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Reservoir main body, 3... Partition wall, 8... Brake fluid injection opening, 9... Step part, 10... Filter integrated, 12... Filter part, 13... Shielding Board, 14
...Reservoir cap, 15...Cap body, 1
6... Membrane plate member, 17... Vacant space, 1B... Recessed space,
19...Passway, 24...Vent hole, 25...Liquid level detector.

Claims (1)

[Scope of utility model registration request] a reservoir cap that has a cavity inside and is attached to the brake fluid injection opening of the reservoir body; a vent hole that is provided on the lower surface of the reservoir cap and communicates the inside of the reservoir with outside air through the cavity; A master comprising: a shielding plate disposed close to and opposite to the lower part of the ventilation hole to prevent brake fluid from entering the ventilation hole; and an integrated filter that engages with the reservoir body and is disposed within the reservoir. In the cylinder reservoir device, the shielding plate is formed from a plate-shaped portion that is integrally provided to the filter and faces the ventilation hole through a portion that extends toward the ventilation hole of the filter. Cylinder reservoir device.