JP2547214Y2 - Master cylinder valve structure - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve structure of a master cylinder used in a brake device of a vehicle or the like.

[0002]

2. Description of the Related Art As a valve structure of a master cylinder of this type, there is a structure described in Japanese Utility Model Laid-Open No. 1-68976. FIG. 5 shows this conventional valve structure, in which a cylinder hole 2 formed in a cylinder body 1 of a master cylinder is provided.
The piston 4 that defines the pressure chamber 3 between the bottom and the bottom has a bottomed tubular portion 5 having a through hole 5A extending on the bottom side of the cylinder hole 2 and extending in the radial direction and extending in the axial direction. A hole 6 and an axial valve hole 7, one end of which opens into the elongated hole 6 and the other end opens at the bottom of the cylindrical portion 5, can be seated on a valve seat 8 around the opening of the valve hole 7. A valve body 10 having a valve portion 9 is disposed with its shaft portion 11 fitted in the valve hole 7 and urged toward the valve seat 8 by a valve spring 12. The end of the shaft portion 11 on the side of the long hole 6 is in contact with and engages with a shaft-shaped valve-opening member 13 that passes through the long hole 6 and is locked on the peripheral wall of the cylinder hole 2. 14
Is a liquid supply chamber, 15 is a through hole, 16 is a return spring, 17 is a boss to which a connection part of a hydraulic fluid reservoir is connected, 18A, 18
B is a sealing member.

FIG. 1 shows a state immediately after the operation of the master cylinder. In a non-operating state, the valve portion 9 is separated from the valve seat 8, and the pressure chamber 3 is provided with a through hole 5A, a valve hole 7, and a long hole 6. The fluid supply chamber 14 communicates with a working fluid reservoir (not shown) through the through hole 15.

When a brake pedal (not shown) is depressed in a non-operating state, the piston 4 is driven toward the bottom of the cylinder hole 2 against the return spring 16 so that the valve portion 9 is seated on the valve seat 8 as shown in FIG. The hole 7 is closed, the supply of the hydraulic fluid from the reservoir (not shown) to the pressure chamber 3 is shut off, and a hydraulic pressure is generated in the pressure chamber 3. The generated hydraulic pressure is discharged from a discharge section (not shown) to a pipe connected to the discharge section, and is supplied to the brake device through the pipe.

[0005]

In this valve structure, one end of the valve spring 12 is received by the step portion 9A of the valve portion 9 while the other end is opened at the bottom end of the cylindrical portion 5 at the bottom of the cylinder hole 2. Is received by a spring receiver 19 disposed on the inner side of the cylinder. The spring receiver 19 is retained by a retaining stopper 20, and the retaining stopper 20 is fitted in the groove 21, so that the internal structure of the cylindrical portion 5 becomes complicated. Has become.

Further, since the processing position of the groove 21 on the cylindrical portion 5 is a fixed position from the bottom of the cylindrical portion 5, the length of the cylindrical portion 5 is changed to facilitate a master cylinder having a different effective stroke. In this case, when the length from the bottom of the cylindrical portion 5 to the groove position changes, and the initial load of the valve spring 12 is set to a constant value, the change in the length is compensated by changing the shape of the spring receiver 19. There is a need to.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and provides a valve structure of a master cylinder in which the structure in a cylindrical portion can be simplified and the spring receiver can have versatility. The purpose is to:

[0008]

In order to achieve the above object, the present invention provides a hole which penetrates a side wall of a cylindrical portion in a radial direction and a projection which is engaged with the hole in a spring receiver. is there.

[0009]

According to the present invention, since the spring receiver is assembled to the cylindrical portion by the projection engagement, the conventional retaining for spring receiving is not required, and the groove processing for this retaining is also unnecessary.

Further, even if the cylindrical portion is attached to a piston having a different length, the length from the bottom of the cylindrical portion to the position where one end of the valve spring engages with the spring receiver does not change. In the case where master cylinders having different effective strokes are prepared by changing the length of the piston, the initial set load of the valve spring can be set to a constant value regardless of whether the master cylinder is attached to the cylindrical portion of any of the pistons.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, a cylindrical portion 30 of a piston (secondary piston) 4 defining a pressure chamber (secondary pressure chamber) 3 between itself and a bottom of a cylinder hole 2 formed in a cylinder main body 1 of a master cylinder is provided. Slot 3 in the radial direction on the bottom 32 side of the peripheral wall 31
3A and 33B are formed, and the opening 34 at the bottom end of the cylinder hole 2 is a straight hole having no inward flange portion.

A spring receiver 40 is inserted and fitted into the cylindrical portion 30 from the opening 34 side. This spring receiver 4
Reference numeral 0 denotes a bottomed cylindrical body as shown in FIGS. 2 to 4, and a square hole 42 is formed in the bottom (the bottom end wall of the cylinder hole 2) 41, and the rear end opening 43 is straight. It is open. Radial positioning slits 42A and 42B extend vertically from the square hole 42. Protrusions 44A, 44B of a predetermined length L extending in the axial direction from the rear end opening 43 to the bottom 41 side are formed on the outer peripheral surface of the spring receiver 40 so as to project in the same direction as the slits 42A, 42B with a diameter therebetween. The projections 44A and 44B extend a predetermined length 1 (<
L) is tapered to be inclined downward toward the rear end opening 43, and from the surface of this tapered portion to the rear end opening 43.
A through hole 45 penetrating through the inner peripheral surface of the portion and opening at the rear end is formed. The spring receiver 40 further includes a projection 44.
A, the 44B respectively separating the 90 ⁰ position, retention slit 46 extending axially from the rear end opening at the rear end is formed. The front end of the slit 46 extends forward from the front ends of the projections 44A and 44B.

Reference numeral 22 denotes a piston (main piston), 2
3 is a pressure chamber (main pressure chamber), 24 is a return spring, 25 is a retainer, 26 is a bolt, and 27 is a sealing device. Parts that are the same as or correspond to those in FIG. 5 are denoted by the same reference numerals.

In this embodiment, the valve body 10 and the valve spring 12 are housed in a spring receiver 40, one end of the valve spring 12 is received by the step 9A of the valve section 9, and the other end is provided at the bottom of the spring receiver 40. Receive in the corner. The spring receiver 40 is configured such that the rear end opening 43 side faces the cylindrical portion 30.
From the opening 34 side of the tubular portion 30 toward the bottom side of the tubular portion 3.
Push it into 0 and assemble it. Since the slit 46 is formed in the spring receiver 40, when the spring receiver 40 is pushed into the cylindrical portion 30, the spring receiver 40 is slightly deformed and pushed in, and the rear end of the spring receiver 40 contacts the bottom 32 of the cylindrical portion 30. When they come into contact with each other, the spring receiver 40 is rotated to fit the protrusions 44A and 44B into the elongated holes 33A and 33B.

Actually, since the automatic assembling is performed, the spring receiver 40 is pushed down to the position where the rear end thereof abuts against the bottom 32 of the cylindrical portion 30, and then the square rotating jig of the automatic assembling machine is squared. 42, and inserts the spring receiver 40 into the projections 44A, 44B.
Rotate until they are fitted into the slots 33A and 33B. After the projections 44A, 44B are fitted into the elongated holes 33A, 33B, the square hole 42 reduces the strength of the square hole 42 so that the square rotating jig can idle, and the projections 44A, 44B
After fitting into the long holes 33A and 33B, the square hole 42 is deformed so that the square rotating jig idles.

As described above, in this embodiment, the spring receiver 40 for receiving one end of the valve spring 12 is fitted inside the tubular portion 30 by projection fitting, and is fitted to the tubular portion 30 to cover the inner surface of the tubular portion 30. Since the valve body 10 and the valve spring 12 are housed in the spring receiver 40, the conventional stopper 20 and the groove 21 for the stopper 20 are not required.

Further, in this embodiment, the valve body 10 and the valve spring 12 are housed in the spring receiver 40 and are assembled to the cylindrical portion 30 by projection fitting, so that the length of the cylindrical portion 30 is reduced. Even when assembled to a different piston, the length from the bottom of the tubular portion 30 to the position where one end of the valve spring 12 engages with the spring receiver 40 does not change. When the master cylinder described above is prepared, the initial set load of the valve spring 12 can be set to a constant value regardless of whether the master cylinder is assembled to the cylindrical portion of any of the pistons.

[0019]

As described above, the present invention employs a configuration in which the spring receiver is assembled to the cylindrical portion by projecting engagement, so that there is no need for the conventional spring receiver retaining groove and the groove processing for this retaining. Therefore, the valve structure can be simplified accordingly, and when preparing a master cylinder having a different effective stroke by changing the length of the cylindrical portion, it is possible to assemble the master cylinder with any of the piston cylindrical portions. In addition, the initial setting value of the valve spring can be set to a constant value, so that the spring receiver can have versatility.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a main part showing an embodiment of the present invention.

FIG. 2 is a plan view of a spring receiver in the embodiment.

FIG. 3 is a longitudinal sectional view of the spring receiver.

FIG. 4 is an end view of the spring receiver.

FIG. 5 is a longitudinal sectional view showing a valve structure of a conventional master cylinder.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder main body 2 Cylinder hole 3 Pressure chamber 4 Piston 7 Valve hole 8 Valve seat 9 Valve part 10 Valve body 11 Shaft 12 Valve spring 30 Cylindrical part 33A, 33B Long hole 40 Spring receiver 42 Square hole 42A, 42B Slit 44A, 44B Projection 45 Through hole 46 Slit

Claims (1)

(57) [Scope of request for utility model registration] 1. A valve hole formed at a pressure chamber side end of a piston with a bottom at the center and connected to a reservoir at the center of the bottom.
There are formed, on the cylindrical portion, a valve body having a valve portion that can be seated on the tubular portion opening peripheral portion which is formed in the valve seat of the shaft portion valve hole which fits into the valve hole, wherein Engages the valve body,
A valve spring for urging the valve body toward the valve seat, and the valve spring
And a spring receiver disposed on a side wall of the cylindrical portion and prevented from coming off, wherein the shaft portion is moved in accordance with the movement of the piston.
In the valve structure of the master cylinder having a valve opening mechanism for opening the valve body, the side wall of the cylindrical portion includes:
While providing a hole penetrating in the radial direction of the cylindrical portion,
That it has formed a projection which engages in the hole to receive the spring
Characteristic master cylinder valve structure.