JPH1035469A - Master cylinder provided with reservoir - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a master cylinder, in which a reservoir is provided, no machining for preventing a slip-off of a sealing member from a cylinder main body is required, and assembly between the cylinder main body and the reservoir can be facilitated. SOLUTION: A distance L1' between a connecting member 23, which connects a cylinder main body 21 and a reservoir 22 together, and a tilt preventing unit 31, which prevents a tilt of the reservoir 22, is set to be longer than a distance L2' between the connecting member 23 and a communication unit 30, which feeds working fluid inside the reservoir 22 to a hydraulic chamber 28 arranged inside the cylinder main body 21. In this way, a reaction force in the tilt preventing unit 31 works on the communication unit 30 while using the connecting member 23 as a fulcrum when an external force works on the reservoir 22, so that a high sealing force corresponding to a distance ratio of the distance L1' between the distance L2' can be obtained. As a result, machining for preventing a slip-off of the sealing member in the cylinder main body 21 can be dispensed with, and assembly between the cylinder main body 21 and the reservoir 22 can be also facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a master cylinder having a reservoir, and more particularly, to a coupling member for coupling a cylinder body and a reservoir, and to one side, hydraulic fluid in the reservoir is supplied to a hydraulic chamber inside the cylinder body. The present invention relates to a device having a connecting portion for supplying and having a tilt preventing portion on the other side for preventing the reservoir from tilting.

[0002]

2. Description of the Related Art As a prior art of this kind, for example, Japanese Utility Model Laid-Open No. 156077/1987 discloses a reservoir connected to a clutch master cylinder. This is shown in FIG.

[0003] The cylinder body 1 and the reservoir 2 are connected by a connecting member 3, and on one side (right side in the figure), a nipple portion 5 of the reservoir 2 is formed in a recess 4 formed in the cylinder body 1. It is fitted via a seal member 6. Inside the cylinder hole 7, lip seals 13, 1
The hydraulic chamber 8 is defined by a piston 12 slidably fitted with the mounting 4, and the hydraulic fluid stored in the reservoir 2 is supplied to the hydraulic chamber 8 through a supply hole 9. .
FIG. 7 shows a detail of a portion where the hydraulic fluid stored in the reservoir 2 is supplied to the hydraulic pressure chamber 8 of the cylinder body 1 as a communication portion 10.

A hook 4 a is formed on the inner peripheral wall surface of the recess 4, a seal member 6 is provided so as to engage with the hook 4 a, and a retaining portion is provided at the tip of the nipple 5 of the reservoir 2. 5a are formed. Thus, the sealing member 6 is prevented from coming out of the recess 4 and the nipple portion 5 is prevented from coming out of the sealing member 6.

On the other side (left side in the figure) of the coupling member 3, the upper end 1a of the cylinder body 1 and the bottom 2a of the reservoir 2 are brought into contact, and the reservoir 2 does not tilt about the coupling member 3. Is formed.

[0006] The tilt preventing portion 11 is connected when the reservoir 2 is pressed downward in the drawing due to an external force, that is, when a device for pumping hydraulic fluid during bleeding of hydraulic fluid is connected to the reservoir 2. Not to prevent tilting around the member 3, of course, a force for pressing the connecting portion 10 downward in the drawing with the reaction force of the tilt preventing portion 11 generated by the external force as a fulcrum using the coupling member 3 as a fulcrum. By doing so, it works to increase the sealing force of the sealing member 6 provided in the connecting portion 10. This sealing force is based on the distance L between the coupling member 3 and the tilt preventing portion 11 according to the leverage principle.
It becomes larger as 1 becomes longer than the distance L2 between the coupling member 3 and the connecting portion 10. That is, the reaction force L1 / L2
Double the sealing force is obtained.

[0007]

However, in the conventional example shown in FIG. 6, the distance L1 is smaller than the distance L2, and thus the generated sealing force is small. For this reason, as described above, the sealing member 6 is engaged with the hook 4a of the recess 4 and the pressing force due to the above reaction force causes the sealing member due to the hydraulic pressure generated in the communication portion 10 during the bleeding of the hydraulic fluid. 6 is prevented from leaking out so as not to cause leakage of the hydraulic fluid.

Therefore, in the conventional example, the cylinder body 1
It is necessary to process the hook 4a for
For this reason, there is a problem that the number of processing steps increases. Further, since the hook 4a is provided, it is not easy to fit the seal member 6 into the recess 4 and there is a problem that the assemblability between the reservoir 22 and the cylinder body 21 is poor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and does not require a process for preventing a seal member from coming off from a cylinder body, and also facilitates assembly of a cylinder body and a reservoir. An object of the present invention is to provide a master cylinder having the same.

[0010]

The object of the present invention is to provide a connecting member for connecting a cylinder body and a part of the bottom of the reservoir by overlapping the cylinder body and a part of the bottom of the reservoir, and a connecting member for the connecting member viewed from the axial direction of the cylinder body. On one side, a nipple portion extending from the bottom of the reservoir is fitted into a recess formed in the cylinder body via a seal member that elastically contacts the bottom of the reservoir, and a cylinder hole of the cylinder body is provided. A communication portion including a supply hole for supplying hydraulic fluid in the reservoir is formed in a hydraulic chamber formed therein, and a side peripheral surface of the cylinder body and a side peripheral surface of the reservoir are joined to the other side. In the master cylinder including a reservoir having a tilt preventing portion that restricts tilting around the coupling member, a distance between the coupling member and the tilt preventing portion is Serial coupling member and a master cylinder having a reservoir, wherein longer than the distance between the contact portion, are solved by.

By making the distance between the connecting member and the tilt preventing portion longer than the distance between the connecting member and the connecting portion,
At the time of bleeding of the hydraulic fluid, the pressing force acting on the connecting portion with the connecting member as a fulcrum generated by the reaction force in the tilt preventing portion becomes large, and the sealing force of the connecting portion also becomes large. Processing for preventing slippage is not required, and the number of processing steps can be reduced. Further, the assemblability of the cylinder body and the reservoir can be improved.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a master cylinder having a reservoir according to each embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a master cylinder provided with a reservoir according to a first embodiment of the present invention.
Indicated by 0. This is used, for example, as a clutch master cylinder used in a clutch operating device.

In the cylinder hole 27 of the cylinder body 21,
Piston 32 with lip seals 33 and 34 attached to front and back
Are slidably fitted in the cylinder hole 27 and define a hydraulic chamber 28 between the piston 32 and the closed end of the cylinder hole 27. The piston 32 is connected to the hydraulic pressure chamber 28.
The drive rod 35 is urged rightward in the figure by a return spring 37 stretched inward, but pushes the piston 32 against a positioning member 41 provided in the opening of the cylinder hole 27.
Abuts to take the illustrated inoperative position. The opening of the cylinder hole 27 is covered with a boot 36.

The cylinder body 21 is connected to the reservoir 22 by a connecting member 23. In the present embodiment, the connecting member 23 uses a spring pin having a C-shaped cross section which can be elastically deformed in the radial direction. One side of coupling member 23 (right side in the figure)
In, the nipple portion 25 of the reservoir 22 is fitted into the recess 24 of the cylinder body 21 via the seal member 26, and the working fluid stored in the reservoir 22 is supplied to the hydraulic chamber 28 of the cylinder body 21. A communication part 30 is formed. On the other side (left side in the figure) of the coupling member 23,
An anti-tilt portion 31 is formed to prevent the reservoir 22 from tilting around the coupling member 23.

The details of the connecting portion 30 will be described with reference to FIG. 2. The opening diameter of the recess 24 is the same up to the bottom, and the outer diameter of the nipple portion 25 is changed to the inner diameter of the recess 24 as shown in the drawing. Hereinafter, a seal member 26 is provided between the inner diameter of the recess 24 and the outer diameter of the nipple portion 25. The hydraulic fluid in the reservoir 22 is supplied to the hydraulic chamber 28 inside the cylinder body 21 through the supply hole 29 and is divided by two lip seals 33 and 34 attached to the piston 32 through the communication hole 42. (See FIG. 1).

Next, the tilt preventing portion 31 will be described.
A projection 39 extending toward the bottom of the reservoir 22 is formed integrally with the cylinder body 21. The bottom of the reservoir 22 has a contact surface 44 that comes into contact with the projection 39. By the part 39 and the contact surface 44,
The tilt prevention unit 31 is configured.

In the present embodiment, referring to FIG. 1, distance L1 'between coupling member 23 and tilt preventing portion 31 is larger than distance L2' between coupling member 23 and connecting portion 30. It is configured to be long.

A cylinder body 21 is provided at the bottom of the reservoir 22 between the coupling member 23 and the tilt preventing portion 31.
The protrusion 40 extends toward the cylinder body 21 and faces the cylinder body 21 with a small gap g as shown in FIG.

The present embodiment is configured as described above. Next, this operation will be described.

When a downward external force acts on the reservoir 22 in FIG. 1, that is, when a device for pumping the hydraulic fluid during bleeding of the hydraulic fluid is connected to the reservoir 22, the reservoir 22 is connected to the connecting member 23 by the tilt preventing portion 31.
And the reaction force of the external force acting on the tilt preventing portion 31 acts as a pressing force against the connecting portion 30 with the coupling member 23 as a fulcrum, and the sealing member 26 serves to increase the sealing force. The pressing force acting on the connecting portion 30 is based on the principle of leverage, and the reaction force L1 '/ L of the tilt preventing portion 31 is determined.
It is 2 'times (L1'> L2 '), and a sealing force of this magnitude can be obtained.

Further, since a slight gap g is provided between the convex portion 40 formed at the bottom of the reservoir 22 and the cylinder body 21, the reservoir 2 is bleed during bleeding of the hydraulic fluid.
When pressure is applied to the bottom of the projection 2, the projection is bent and bent.
0 is brought into contact with the cylinder body 21 to prevent the bottom of the reservoir 22 from being deformed and damaged. Also,
The reaction force generated when the convex portion 40 is pressed against the cylinder body 21 acts as a pressing force against the connecting portion 30 with the coupling member 23 as a fulcrum. That is, the tilt prevention unit 31
In addition, it acts to increase the sealing force of the connecting portion 30.

Thus, according to the present embodiment, the sealing member 26 can be prevented from coming off only by the reaction force of the external force acting on the reservoir 22, and the recess 24 of the cylinder body 21 can be obtained as in the conventional example. Accordingly, the processing for preventing the seal member from coming off can be omitted, and the number of processing steps for the cylinder body 21 can be reduced. Further, assembling of the cylinder body 21 and the reservoir 22 becomes easier than before, and productivity can be improved.

The overall operation of the master cylinder 20 will be described. A drive rod 35 driven by depressing a clutch pedal (not shown) pushes the piston 32 forward (to the left in the figure) against the spring force of the return spring 37. When you move,
The lip seal 33 cuts off the fluid communication with the supply hole 29, and the hydraulic chamber 28 is partitioned. When the piston 32 is further pushed, a hydraulic pressure is generated in the hydraulic pressure chamber 28, and the generated hydraulic pressure is supplied from the output hole 38 to a clutch operating device (not shown).
When the depression of the clutch pedal is released, the piston 32
Moves backward (to the right in the figure) by the hydraulic pressure in the hydraulic chamber 28 and the spring force of the return spring 37, and returns to the inoperative position shown in FIG.

FIG. 5 shows a master cylinder provided with a reservoir according to a second embodiment of the present invention.
The same reference numerals are given to portions corresponding to FIG. 1, and detailed description thereof will be omitted.

That is, in the present embodiment, the tilt preventing portion 5
5 is different from the tilt preventing portion 31 in the first embodiment described above in that the protrusion 53 is integrally formed on the bottom of the reservoir 52 and the protrusion 53 is formed on the cylinder body 51.
The contact surface 54 is formed so as to abut the contact surface.

Also in this embodiment, the distance L1 "between the coupling member 23 and the tilt preventing portion 55 is set to be longer than the distance L2" between the coupling member 23 and the connecting portion 30. And the projections 40 of the reservoir 52
Are formed so as to have a slight gap with the cylinder body 51.

This embodiment performs the same operation as that of the above-described first embodiment, and this embodiment can also obtain the same effect as that of the first embodiment.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited to these embodiments.
Various modifications are possible based on the technical idea of the present invention.

For example, in the first embodiment described above, the protrusion 39 is formed on the cylinder body 21 side and the contact surface 44 is formed on the reservoir 22 side to form the tilt preventing portion 31, and the second embodiment is performed. In the embodiment, the projecting portion 53 is formed on the reservoir 52 side, and the abutment surface 54 is formed on the cylinder body 51 side to form the tilt preventing portion 55. However, the projecting portions are formed on both the cylinder body side and the reservoir side. Alternatively, a tilt preventing portion may be formed by forming a contact surface on each of the projecting portions with which the opposing projecting portions abut.

As shown in FIG. 4, a recess 60 is formed in the contact surface 61 of the reservoir 58 so that the protrusion 59 on the cylinder body 57 side can be engaged with the contact surface 61. Is also good. In this case, the movement (rack) of the reservoir 58 in the radial direction of the cylinder body 57 can be restricted.

Although the protrusions of the tilt preventing portions can be formed as separate members, it is more convenient to integrally form the protrusions when forming the cylinder body and / or the reservoir by using a mold. The tilt preventing portion can be formed without increasing the number of parts.

In each of the above-described embodiments, the protrusions 4 opposed to each other while maintaining a small gap g in the cylinder bodies 21 and 51 are provided.
Although 0 is formed on the bottom of the reservoirs 22 and 52, it may be formed on the cylinder body side.

In each of the above embodiments, the opening diameter of the recess 24 of the cylinder body is the same up to the bottom, but as described above, the tilt preventing portions 31, 55 and the convex portions 40, 4
0 provides a large pressing force against the connecting portion 30, so that even if the opening diameter is gradually reduced toward the bottom of the recess, an effect of preventing the sealing member 26 from coming off can be obtained. Can be.

[0035]

As described above, according to the master cylinder provided with the reservoir of the present invention, the processing for preventing the sealing member from coming off the cylinder body is unnecessary.
Processing man-hours can be reduced. Further, assembling of the cylinder body and the reservoir becomes easy, and the production efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a master cylinder provided with a reservoir according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part in FIG.

FIG. 3 is an enlarged view of another main part in FIG. 1;

FIG. 4 is a partially enlarged view showing a modification of the present invention.

FIG. 5 is a sectional view showing a master cylinder provided with a reservoir according to a second embodiment of the present invention.

FIG. 6 is a cross-sectional view showing a master cylinder including a conventional reservoir.

FIG. 7 is an enlarged view of a main part in FIG. 6;

[Explanation of symbols]

 Reference Signs List 20 master cylinder 21 cylinder body 22 reservoir 23 connecting member 24 concave portion 25 nipple portion 26 sealing member 27 cylinder hole 28 hydraulic chamber 29 replenishing hole 30 communication portion 31 tilt preventing portion 39 projecting portion 40 convex portion 44 contact surface 50 master Cylinder 51 Cylinder main body 52 Reservoir 53 Projecting part 54 Contact surface 55 Tilt prevention part 60 Recess

Claims (5)

[Claims] A coupling member that overlaps the cylinder body and a part of the bottom of the reservoir to couple the cylinder body and the reservoir,
On one side of the coupling member as viewed from the axial direction of the cylinder body, with respect to a recess formed in the cylinder body,
A nipple portion extending from the bottom of the reservoir is fitted via a seal member elastically contacting the bottom of the reservoir, and a hydraulic chamber formed in a cylinder hole of the cylinder body is supplied with hydraulic fluid in the reservoir. A connecting portion including a supply hole to be formed, and a side circumferential surface of the cylinder body and a side circumferential surface of the reservoir are joined to the other side, and a tilting for restricting tilting about the connecting member. In a master cylinder provided with a reservoir having a prevention part, a distance between the coupling member and the tilt prevention part is longer than a distance between the coupling member and the communication part. Equipped master cylinder. 2. The tilt preventing portion extends from the bottom side of the reservoir to the cylinder body side and / or extends from the cylinder body side to the bottom side of the reservoir, and contacts the projection portion. The master cylinder provided with a reservoir according to claim 1, comprising a contact surface. 3. The master cylinder having a reservoir according to claim 1, wherein the contact surface includes a concave portion with which the protruding portion can be engaged. 4. A projection projecting from the bottom of the reservoir toward the cylinder body, or a projection projecting from the cylinder body toward the bottom of the reservoir, between the coupling member and the tilt preventing portion. The master cylinder provided with a reservoir according to any one of claims 1 to 3, wherein the master cylinder is opposed to the bottom of the cylinder body or the reservoir with a small gap. 5. The opening diameter of the recess facing the bottom of the reservoir is the same as the opening up to the bottom of the recess, or is gradually reduced toward the bottom of the recess. The outer diameter of the portion fitted into the recess is not more than the inner diameter of the bottom of the recess, and the seal member is provided between the inner diameter of the recess and the outer diameter of the nipple portion. A master cylinder comprising the reservoir according to any one of claims 1 to 4.