JPS5943159Y2 - Reservoir cap in master cylinder - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a reservoir cap that is buttoned on a master cylinder.

The cap of the reservoir attached to the master cylinder is provided with a vent hole to keep the inside of the reservoir in constant communication with the atmosphere.

This vent hole is designed in various ways to prevent oil from leaking from the reservoir to the outside through the vent hole due to vibration.

The most common example is a cap with a plurality of hollow chambers through which atmospheric air is introduced into the reservoir.

However, in conventional devices with such a configuration, the oil liquid in the reservoir body is discharged from the reservoir body into the first hollow chamber due to continuous vibration over a long period of time, and a part of it is also discharged into the first hollow chamber. A portion of the liquid is discharged into two hollow chambers, and then a portion of the liquid is sequentially discharged into the next hollow chamber, and finally leaks out of the reservoir cap.

The inventors believe that the leakage phenomenon in conventional reservoirs is that the next discharge occurs before the oil discharged into the hollow chamber is sufficiently refluxed, and that the oil is discharged into the second hollow chamber and subsequent chambers. The oil liquid flows back into the reservoir body through each hollow chamber in reverse order, so based on the assumption that this is due to the fact that it takes time for the reflux to occur, the second hollow chamber is Very good results were obtained by configuring the third hollow chamber and the third hollow chamber to form one hollow chamber, thereby allowing the oil in the third hollow chamber to flow back into the reservoir body without passing through the second hollow chamber. I was able to do that.

The present invention will be explained below with reference to embodiments shown in the drawings.

FIG. 1 is a longitudinal cross-sectional view of a part of the reservoir body and the entire cap of the master cylinder according to the present invention.

The cap 1 according to the present invention includes an outer cap 2, an inner cap 3, and a plate 4.

The outer cap 2 has a small diameter cylindrical body 5 on its central lower surface.
is provided protrudingly, and a ventilation hole 6 is formed at its lower end.

The inner cap 3 has a large-diameter cylindrical body 7 protruding from its upper central surface, and a ventilation hole 8 protruding from its bottom.

The plate 4 has a ventilation hole 9 penetrating through its center, has leg portions 10 protruding from its lower circumferential surface, and has an annular convex portion 11 protruding from its upper circumferential surface.

These outer cap 2, inner cap 3 and plate 4 are assembled together to form a cap 1 as shown in FIG.
is fitted into the

As a result, inside the cap 1, there is a recess 13 formed by the small diameter cylindrical body 5 of the outer cap 2, an annular space formed by the small diameter cylindrical body 5 of the outer cap 2, and the large diameter cylindrical body 7 of the inner cap 3. 14, and a first hollow chamber 15 consisting of the lower surface of the plate 4 and the large diameter cylindrical body T of the inner cap 3.

The term "hollow chamber" used in the present invention refers to a chamber whose entire structure is completely covered with four walls, and where the hollow chambers are communicated with each other through ventilation holes protruding from the iron wall.

Therefore, as indicated by the arrow in FIG. A ventilation hole 17 formed, an annular hollow chamber (fourth hollow chamber) 18 formed on the outer circumferential side of the cylindrical body 7 of the inner cap 3, a bottom surface of the outer cap 2 and the top of the cylindrical body 7 of the inner cap 3. A ventilation hole 19 formed between the end surface, an annular space 14 formed by the cylindrical body 7 of the inner cap 3 and the cylindrical body 5 of the outer cap 2, a lower end of the cylindrical body 5 of the outer cap 2, and the plate. 4, the large hollow chamber A, the vent hole 9 of the plate 40, the first hollow chamber 15, and the vent hole 8 of the inner camp 3 into the reservoir body 12.

Note that 21 in FIG. 1 is a filter.

FIG. 2 (I) is an enlarged view of the main part of FIG. 1, and shows the stable state of the reservoir, that is, the normal state in which the cap 1 is not vibrated to the extent that it moves the plate 4 up and down. .

In this state, if a large vibration or the like occurs in the reservoir, the plate 4 inside the cap 1 will jump up as shown in FIG. , the lower opening of the recess 13 in the cap 1
and the lower opening of the annular space 14, respectively, to separate the large hollow chamber A into a second hollow chamber 22 and a third hollow chamber 23, respectively.

During this time, the oil that leaked out of the reservoir body 12 through the vent hole 8 of the inner cap 3, the first hollow chamber 15, and the vent hole 9 of the plate 40 accumulates in the second hollow chamber 22, and a part of the oil leaks through the vent hole 9 of the inner cap 3. 6 and flows out into the third hollow chamber 23.

However, since the passage area of the vent hole 6 is formed to be relatively small, a throttling effect acts on the oil passing through the vent hole 6, increasing its discharge resistance.

As a result, only a very small amount of oil flows out into the third hollow chamber 23.

Specifically, in the case where the ventilation hole 6 is not formed, the plate 4 may have a small diameter cylindrical shape of the outer cap 2 depending on the setting conditions such as the material and weight of the plate 4 or the size of the passage area of the ventilation hole 80. When it comes into contact with the lower end of the body 5, the plate 4 may stick to the lower end of the small diameter cylindrical body 5 due to the viscosity or surface tension of the brake fluid.
The effect of damping the scattering of the brake fluid in the hollow chamber 15 due to vibration is reduced.

However, since the cap according to the present invention is provided with the vent hole 6, the second hollow chamber 22 communicates with the third hollow chamber 23 and the first hollow chamber 15 through the vent hole 6.9, respectively. There is no possibility that the plate 4 will stick to the small diameter cylindrical body 5.

Since the cut vent hole 6 is formed in the horizontal direction perpendicular to the vibration direction of the reservoir, together with the throttling effect (orifice effect) of the vent hole 6, it has the effect of damping the splashing of brake fluid. Furthermore, the amount of brake fluid discharged into the third hollow chamber 23 can be kept to a very small amount.

Subsequently, when the plate 4 returns to the state shown in FIG. 2(I), the second hollow chamber 22 and the third hollow chamber 23 are opened and become the large hollow chamber A in which they are integrated again.

Therefore, the oil accumulated in the second hollow chamber 22A and the third hollow chamber 23 immediately falls into the first hollow chamber 15 from the vent hole 9 of the plate 4, and further passes through the vent hole 8 of the inner cap 3. It falls into the reservoir body 12 again.

If the vibrations generated in the reservoir are continuous, the above action will be repeated.

That is, during this period, the plate 4 moves up and down almost in synchronization with the discharge movement of the oil from the reservoir body 12, and during the discharge period, the oil flows out through the second hollow chamber 22 into the third hollow chamber 23, and the discharge is stopped. During the period, the oil liquid accumulated in the third hollow chamber 23 is transferred to the second hollow chamber 23.
Reflux is made into the reservoir body 12 without passing through the hollow chamber 22.

At this time, since the throttling effect of the vent hole 6 does not act on the oil liquid flowing back, the resistance to the flow back is small, and the oil liquid smoothly flows back into the reservoir body 12.

As described above, the present invention has the plate 4 installed in the inner cap 30 so as to be movable up and down, and when the plate 4 is in the uppermost position, a plurality of hollow chambers, e.g. The hollow chamber 22 and the third hollow chamber 23 are separated, thereby preventing leakage of the oil inside the reservoir body 12 as much as possible. Hollow chamber 22, third
Basically, the hollow chambers 23 are opened to each other to form a large hollow chamber A that integrates them, and the oil liquid accumulated in each hollow chamber is directly refluxed into the reservoir body 12 through the vent hole 9 of the plate 4. It is a concept and can take various forms within the scope of a claim for utility model registration.

As described above, in the reservoir cap of the master cylinder according to the present invention, the plate springs up almost in synchronization with the oil discharged from the reservoir body due to vibration, and the plate separates a plurality of hollow chambers on the plate. By doing so, leakage of oil liquid is concealed as much as possible, and when the plate is lowered, the plurality of hollow chambers are released, and the oil liquid accumulated in each hollow chamber is released without passing through other hollow chambers. Since the oil is directly refluxed into the reservoir body through the vent holes in the plate, the oil is quickly refluxed, and leakage of the oil within the reservoir body can be reliably prevented.

Moreover, since the plurality of hollow chambers are communicated with each other through the ventilation holes of the small-diameter cylindrical body, even when the hollow chambers are separated, the inside of the reservoir body and the atmosphere are always communicated through the ventilation holes. Therefore, no unexpected pressure is applied to the oil level in the reservoir, and malfunction of the brake system is reliably prevented.

In addition, since the weight of the oil stored in the hollow chambers acts directly on the plates, the plates that have moved upward quickly and reliably return to their original positions due to their own weight and the weight of the oil, and inside each hollow chamber. The oil liquid is smoothly returned to the reservoir body.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a part of the reservoir body and the entire cap of the master cylinder according to the present invention, and Figure 2 (I) is an enlarged cross-sectional view of the main part, with the plate in the normal position. FIG. 2(n) is an enlarged cross-sectional view of the main part showing the state in which the plate is in the raised position. 1... Cap, 2... Outer cap, 3... Inner cap, 4...
・Plate, 5...Small diameter cylindrical body, 6...
・Vent hole, 7...Large diameter cylindrical body, 9...
Ventilation hole, 12... Reservoir body, 13...
... Concavity, 14 ... Annular space, 22 ...
・Second hollow chamber, 23...Third hollow chamber.

Claims (1)

[Claims for Utility Model Registration] The upper end opening of the reservoir of the master cylinder is covered twice with an inner cap and an outer cap each having a ventilation hole, and a plurality of hollow chambers communicating with each other are formed between the two caps. forming one of the hollow chambers in communication with the interior of the reservoir through a vent hole in the inner cap, and communicating the other hollow chamber with the outside of the reservoir through a vent hole in the outer cap. a) the upper surface of the upper air inner cap 3; b) a large-diameter cylindrical body 7 that protrudes from the outer cap 2 and surrounds the ventilation hole 8; and b) a small-diameter cylindrical body that protrudes from the lower surface of the outer cap 2 and loosely fits into the inner periphery of the large-diameter cylindrical body 7. C) the upper end of the large-diameter cylindrical body 7 and the small-diameter cylindrical body 5;
d) ventilation holes 19.6 formed at the lower ends of the large diameter cylindrical body 7, and d) between the lower end of the small diameter cylindrical body 5 and the upper surface of the inner cap 3, a plate 4 arranged to be slidable in the vertical direction; e) a ventilation hole 9 formed in the plate 4 and opening facing the inside of the small diameter cylindrical body 5; and f) a lower surface of the plate 4. a first hollow chamber 15 formed between the large-diameter cylindrical body 7 and the upper surface of the inner cap 3; g) when the plate 4 abuts the lower end of the small-diameter cylindrical body 5; A second cylindrical body formed between the small diameter cylindrical body 5, the upper surface of the plate 4, and the lower surface of the outer cap 2
a) a third hollow chamber formed between the large-diameter cylindrical body 7 and the small-diameter cylindrical body 5, and the plate 4 is located at the lower end of the small-diameter cylindrical body 5. When the inner cap 3 contacts the vent hole 8 of the inner cap 3, the inside of the reservoir communicates with the first hollow chamber 15 through the vent hole 8 of the inner cap 3, and the first hollow chamber 15 communicates with the vent hole 9 of the plate 4.
The third hollow chamber 23 communicates with the outside of the reservoir through the ventilation hole 19 at the upper end of the large diameter cylindrical body 7 and the ventilation hole in the outer cap. A reservoir cap characterized in that it is configured to be open to the user.