JP2549171Y2 - Grommet seal of reservoir for master cylinder - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to a pair of cylindrical mounting portions formed on an upper surface of a master cylinder main body and a pair of cylindrical mounting portions formed on an upper surface of a reservoir main body and fitted to an inner periphery of the cylindrical mounting portion. The present invention relates to a grommet seal for a reservoir for a master cylinder, which is mounted between the grommet seal and the leg portion.

[0002]

2. Description of the Related Art A grommet seal for a master cylinder reservoir is disclosed in Japanese Patent Publication No. 57-36182. At the lower end of the grommet seal is formed a pair of seal lips which open bifurcatedly toward the master cylinder body side, and the radially inner seal lip is brought into contact with the outer periphery of the cylindrical leg portion of the reservoir body, and An outer seal lip is brought into contact with the inner periphery of the cylindrical mounting portion of the master cylinder main body, and when the internal pressure of the master cylinder main body is increased, the two seal lips are urged in directions away from each other to form the cylindrical leg and the cylinder. The seal is made to come into contact with the shape mounting portion.

[0003]

By the way, filling of the brake system with hydraulic oil after completion of assembly of the vehicle is performed by supplying pressurized hydraulic oil from an oil supply port of a reservoir. At this time, when the pressurized hydraulic oil is filled from the reservoir into the master cylinder body, pressure acts on the lower surfaces of a pair of seal lips formed at the lower end of the grommet seal, and the pressure is applied to the master cylinder by the master cylinder. Push up to separate it from the body. As a result, the seal lip of the grommet seal deviates from the fixed position, the sealing performance between the master cylinder main body and the reservoir main body is reduced, and oil leakage may occur from the grommet seal.

The present invention has been made in view of the above circumstances, and has as its object to prevent leakage of hydraulic oil from a grommet seal when pressurizing and filling hydraulic oil into a master cylinder.

[0005]

In order to achieve the above object, the present invention provides a cylindrical mounting portion formed on an upper surface of a master cylinder body and a cylindrical mounting portion formed on a lower surface of a reservoir body. In the grommet seal of the reservoir for the master cylinder mounted between the cylindrical leg fitted to the inner periphery, between the inner periphery of the cylindrical mounting portion of the master cylinder main body and the outer periphery of the cylindrical leg of the reservoir main body. the lower end of the cylindrical main body portion which is sandwiched, to form a pair of upper and lower seal lips projecting into two radially inward, is brought into contact with the sealing lips of the upper to the lower surface of the cylindrical leg portion of the reservoir body The lower seal lip is brought into contact with the bottom surface of the cylindrical mounting portion of the master cylinder body.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

1 to 4 show an embodiment of the present invention. FIG. 1 is a sectional view of a master cylinder and a reservoir, and FIG.
Is a sectional view taken along line 2-2 of FIG. 1, FIG. 3 is an enlarged view of a part 3 of FIG. 1, and FIG. 4 is a sectional view of a grommet seal alone.

As shown in FIG. 1, a tandem type master cylinder M for an automobile is a substantially cylindrical master cylinder body 1.
Is provided. In the cylinder hole 2 of the master cylinder body 1,
To form first and second hydraulic chambers 3 _1, 3 picture ₂ back and forth independent of each other, a pair of piston 4 around _1, 4 ₂ are fitted slidably. These pistons 4 ₁ and 4 ₂ are provided with return springs 5.
It is biased to respective backward direction by _1, 5 _2.

[0009] retreat limit of the front piston _{4. 1,} the distal end portion of the stop bolt 6 screwed into the lower wall of the master cylinder body 1 is restricted by supporting the piston 4 _1.
The retraction limit of the rear piston 4 _2, bearing 7 fixed to the rear end inner wall of the cylinder bore 2 is restricted by supporting the piston 4 _2. The rear piston 4 ₂ the bearing 7
An output rod 9 of a negative pressure booster operated by a brake pedal (not shown) is connected to a rear end of the piston rod 8 which is slidably supported by the piston rod 8. The first hydraulic chamber 3 ₁ and the second hydraulic chamber 3 _2, first connects to a brake cylinder (not shown) output port 10 ₁
And a second output port 10 ₂ are opened, respectively.

A pair of front and rear cylindrical mounting portions 11 ₁ and 11 ₂ are integrally formed on the upper surface of the master cylinder body 1. The bottom of the front of the cylindrical mounting portion 11 _1, the relief port 12 ₁ and the supply port 13 ₁ for communicating with the first hydraulic chamber 3 ₁
Relief port 1 but is drilled at a distance from each other in the front and rear, the tubular mounting portion 11 ₂ of the bottom surface of the rear side, which communicates with the second hydraulic chamber 3 ₂
2 ₂ and supply port 13 ₂ are drilled at a distance from each other in the front and rear.

The reservoir R supported on the upper portion of the master cylinder M is a reservoir body 14 integrally formed of synthetic resin.
And a cap 1 for opening and closing a filler port formed on the upper surface thereof
5 is provided. On the upper surface of the bottom wall of the reservoir body 14, a partition wall 16 for partitioning the inside of the reservoir body forward and backward is provided. Partition wall 1
6 when the reservoir R is inclined in the longitudinal direction, holding the hydraulic oil to the first half and the second half portion, the supply of hydraulic oil to function uninterrupted with respect to the first hydraulic chamber 3 ₁ and the second hydraulic chamber 3 ₂ . The pair of front and rear cylindrical mounting portions 11 formed on the master cylinder main body 1 are formed on the lower surface of the bottom wall of the reservoir main body 14.
_1, 11 ₂ to grommet seal G of each rubber, G
The cylindrical leg portions 17 ₁ , 17 ₂ connected via the _{first member} are integrally formed.

Referring to FIG. 2 together, it is apparent that
A mounting bracket 18 projecting from the upper surface of the master cylinder main body 1 is overlapped with a mounting bracket 19 projecting from the lower surface of the bottom wall of the reservoir main body 14, and is joined by bolts 20. At this time, a metal distance collar 21 is mounted on the mounting bracket 19 of the reservoir body 14 so that the tightening force of the bolt 20 does not directly act on the synthetic resin mounting bracket 19.

As is apparent from FIGS. 3 and 4, the grommet seal G is provided on the inner periphery of the cylindrical mounting portions 11 ₁ and 11 ₂ on the master cylinder main body 1 side and the cylindrical leg portions 17 ₁ and 17 on the reservoir main body 14 side. 17 tubular body portion 22 which is sandwiched between the _second outer peripheral
Is provided. At the upper end of the cylindrical main body 22, a flange portion 23 sandwiched between a step 11a protruding radially outward and formed on the upper surfaces of the cylindrical mounting portions 11 ₁ and 11 ₂ and the lower surface of the reservoir main body 14 is provided. Is formed.

At the lower end of the cylindrical body 22, a pair of upper and lower seal lips 24 _U , 2 protruding radially inward and bifurcated.
4 _L are formed. Upper surface of the upper seal lip 24 _U is a reservoir body 14 of the tubular Joashi portion 17 _1, 17 stepped portion ₂ of the bottom surface to an annular seat 17a formed through an elastically abuts and the lower side of the seal lip The lower surface of 24 _L elastically abuts an annular seat portion 11 b formed on the outer periphery of the bottom surface of the cylindrical mounting portions 11 ₁ and 11 ₂ of the master cylinder main body 1 so as to be slightly higher on the outer side in the radial direction. . The portion sandwiched between the pair of upper and lower seal lips 24 _U and 24 _L faces a space 25 communicating with the inside of the master cylinder body 1 and the reservoir body 14. Between the upper seal lip 24 _U tip and the cylindrical Joashi unit 17 _1, 17 ₂ of the lower end outer periphery in advance a slight gap is formed.

Three annular projections 26 and two annular projections 27 project from the outer circumference and the inner circumference of the cylindrical main body 22, respectively. The three outer circumference projections 26 are cylindrical mounting portions. 11
_1, 11 while being slightly compressed in contact with the inner periphery of the _2, ... inner periphery of three of the annular projection 27 is cylindrical Joashi unit 17 _1, 1
It is slightly compressed in contact with the outer periphery of the 7 _2.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

[0017] rear piston 4 ₂ pressed by the output rod 9 of the vacuum booster is advanced while compressing the spring 5 ₂ return through the relief port 12 _2, the brake hydraulic pressure generated in the second hydraulic chamber 3 ₂ is transmitted from the second output port 10 ₂ to the brake cylinder, to brake the corresponding wheel. Wherein with the advancement of the rear piston 4 _2, it is advanced while compressing the spring 5 _first spring 5 _{and second} spring force and the hydraulic braking pressure generated in the second hydraulic chamber 3 ₂ returns the front piston 4 ₁ back. When the front piston 4 ₁ passes through the relief port 12 _1,
Brake hydraulic pressure generated in the first hydraulic chamber 3 ₁ is transmitted from the first output port 10 ₁ to the brake cylinder, to brake the corresponding wheel.

When the cap 15 of the reservoir body 14 is removed and the brake system is pressurized and filled with hydraulic oil after the assembly of the vehicle is completed, the hydraulic oil is supplied to the inside of the cylindrical legs 17 ₁ and 17 ₂ of the reservoir body 14. Then, the air flows into the master cylinder M through the space 25, and further flows into the brake cylinder through a pipe.

At this time, the filling pressure is set to a pair of upper and lower seal lips 24 _U and 2 of the grommet seal G facing the space 25.
4 _L is pushed up and down, and the upper surface of the upper seal lip 24 _U is pressed against the seat 17 a of the cylindrical legs 17 ₁ and 17 ₂ ,
Further, the lower surface of the lower seal lip 24 _L is attached to the cylindrical mounting portion 11.
_1, 11 is pressed against the _second seat 11b. Thereby, a pair of seal lips 24 _U and 24 _L of the grommet seal G are provided.
Are cylindrical leg portions 17 ₁ and 17 ₂ and cylindrical mounting portions 11 ₁ and 11 ₂
And the leakage of hydraulic oil from the grommet seal G is reliably prevented.

At this time, the pressure of the working oil acting on the grommet seal G is directed outward in the radial direction of the grommet seal G as shown by an arrow a in FIG. Therefore, even if the pressure of the hydraulic oil acts, the grommet seal G is not pushed upward from the cylindrical mounting portions 11 ₁ and 11 _{2 of the} master cylinder main body 1, and the deterioration of the sealing performance is prevented.

When the grommet seal G is mounted, the three annular projections 26 projecting from the outer periphery of the cylindrical main body 22 are brought into close contact with the inner periphery of the cylindrical mounting portions 11 ₁ and 11 _2. The two annular projections 27 projecting from the inner periphery of the cylindrical main body 22 are compressed in close contact with the outer periphery of the cylindrical legs 17 ₁ and 17 ₂ , so that the pair of seal lips 2
Combined with the sealing action of 4 _U , 24 _L , leakage of hydraulic oil is more reliably prevented.

Further, since the distance between the pair of cylindrical mounting portions 11 ₁ and 11 ₂ does not match the distance between the pair of cylindrical leg portions 17 ₁ and 17 ₂ , the corresponding cylindrical mounting portions 11 ₁ and 11 2 are provided. _Two
Even if the relative positions of the cylindrical legs 17 ₁ and 17 ₂ in the radial direction are shifted, the error can be absorbed by the amount of compression of the annular protrusions 26. At this time, since the pre-gap between the upper seal lip 24 _U tip and the cylindrical Joashi unit 17 _1, 17 ₂ of the lower end outer periphery is formed, the error affects the upper seal lip 24 _U Is prevented.

Although the embodiment of the present invention has been described in detail, the present invention is not limited to the above embodiment, and various design changes can be made.

For example, in the embodiment, the reservoir R is supported on the master cylinder M via two grommet seals G, G. However, the reservoir R is supported on the master cylinder M via one grommet seal G. It is also possible.

[0025]

As described above, according to the present invention, the cylindrical main body of the grommet seal is replaced with the cylindrical mounting of the master cylinder main body.
Between the inner circumference of the attachment part and the outer circumference of the cylindrical leg of the reservoir body.
In rare cases, the mounting position is securely fixed in the radial direction
At the bottom, it is formed at the lower end of the cylindrical
A pair of upper and lower seal lips that project bifurcated
The lower surface of the cylindrical leg of the server body and the cylindrical shape of the master cylinder body
Since each of the mounting portion bottom and so as to abut, when pressurized filling the hydraulic fluid from the reservoir to the master cylinder, wide its filling pressure presses the upper and lower seal lips above and below
The upper seal lip under the cylindrical leg of the reservoir body.
Insert the seal lip on the master cylinder
Make sure that the bottom of the cylindrical mounting part
Therefore, leakage of hydraulic oil can be effectively prevented. Moreover, the pressure of the hydraulic oil, grommet seal
To affect <br/> radially outwardly relative to the bifurcated portion of the lower end (in particular the border portion of the upper and lower seal lips), each with grommet seal is extruded from the tubular mounting portion of the master cylinder body in the axial direction by the pressure Misalignment of seal lip
Such a fear is eliminated, and therefore, the fixed state as described above
Coupled with the sealing effect of the lower cylindrical body itself,
Inner circumference of the cylindrical mounting part of the star cylinder body and the cylinder of the reservoir body
Between Joashi outer periphery, the sealing property at the time of the hydraulic oil filling
Ru can be kept securely.

[Brief description of the drawings]

FIG. 1 is a sectional view of a master cylinder and a reservoir.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged view of a part of FIG. 1;

FIG. 4 is a sectional view of a single grommet seal.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Master cylinder main body 11 ₁ , 11 ₂ Cylindrical mounting part 14 Reservoir main body 17 ₁ , 17 ₂ Cylindrical leg 22 Cylindrical main body 24 _U Upper seal lip 24 _L Lower seal lip

Claims (1)

(57) [Scope of request for utility model registration] 1. A tubular mounting portion formed on the upper surface of the master cylinder body (1) (11 _1, 11 ₂₎ and the cylindrical mounting portion formed on the lower surface of the reservoir body (14) (11 _1,
11 ₂ ) A cylindrical leg (17 ₁ , 17 ₂ ) fitted to the inner circumference
In the grommet seal of the reservoir for the master cylinder, which is mounted between the cylinder mounting portion and the cylindrical mounting portion (11 ₁ , 11) of the master cylinder body (1).
Inner circumference and the reservoir tube Joashi portion of the body (14) ₂₎ (1
7 _1, cylindrical main body which is sandwiched between the outer circumference of the 17 ₂₎ (2
The lower end of 2), to form a pair of upper and lower seal lips projecting into two radially inwardly (24 _U, 24 _L), the reservoir body and the seal lip (24 _U) of the <br/> upper (14 )
Abutting against the lower surface of the cylindrical legs (17 ₁ , 17 ₂ ) of the master cylinder body (1 1) and the lower sealing lip (24 _L ) of the cylindrical mounting portions (11 ₁ , 11 ₂ ) of the master cylinder body (1). A grommet seal for the reservoir for the master cylinder, which is in contact with the bottom surface.