JP2588760Y2 - Hydraulic shock absorber detent mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detent mechanism for a hydraulic shock absorber used for a vehicle or the like.

[0002]

2. Description of the Related Art As a conventional damping force adjusting device for a hydraulic shock absorber, as described in Japanese Utility Model Publication No. Hei 2-11633, a fixed orifice for bypassing a piston oil passage to a rod end integral with a hollow rod. Is formed, and a plurality of orifices having different diameters are formed on the outer periphery of the select valve provided at the lower end of the adjuster rod rotatably inserted into the hollow rod, and the orifice which rotates the select valve and communicates with the fixed orifice is formed. There is one in which the damping force can be adjusted by making a selection.

In this damping force adjusting mechanism,
A detent in which a plurality of conical grooves are formed in a row in the circumferential direction on the upper surface of the select valve, and one locking ball that can be fitted into the conical groove of the select valve is biased by a spring at the lower end of the hollow rod. A mechanism is provided.

[0004]

However, in the above-described detent mechanism of the hydraulic shock absorber, a plurality of conical grooves are formed in one row, and one locking ball that can be fitted into the conical grooves. Is only provided by biasing with a spring, which not only has a poor moderation feeling, but also causes the select valve to fall down due to the reaction force of the spring at only one point of the select valve, resulting in a modest feeling of moderation A feeling is accompanied, and variation in the damping force is increased.

[0005]

According to the present invention, in order to solve the above-mentioned problems, two rows of a plurality of conical grooves are formed in one member in the circumferential direction, and each row is provided with a dead zone in a symmetrical position. And two engaging balls engageable with the conical grooves of each row are biased by a spring on the other member and disposed at symmetrical positions.

[0006]

The two engaging balls respectively urged by the springs are provided at symmetric positions of the other member, and the conical grooves in which the engaging balls can be engaged are formed in two rows in the circumferential direction of one member. However, each row is provided with a dead zone at a symmetrical position, so that a sense of moderation is improved, and the other member receives a spring reaction force at a symmetrical position, so that the sense of stiffness is reduced, Variation in damping force is also reduced.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings. Here, FIG. 1 is a sectional view of a hydraulic shock absorber to which the detent mechanism according to the present invention is applied, FIG. 2 is an enlarged sectional view of a main part of FIG. 1, FIG. 3 is a plan view of a valve stopper, and FIG.
FIG. 5 is a sectional view taken along the line A, FIG. 5 is a bottom view of the select valve,
FIG. 6 is a sectional view taken along the line BB of FIG. 5, and FIG.
FIG. 8 is a sectional view taken along the line C, and FIG. 8 is a plan view of the select valve.

The cylinder 1 is closed by mounting an end cap 2 at an upper end and a bottom cap 3 at a lower end, and is closed in the cylinder 1 from above through a rod guide 4 and an oil seal 5. The rod 6 is inserted, and a hollow rod end 7 is screwed to the lower end of the hollow rod 6.

A piston 8 which is in sliding contact with the inner peripheral surface of the cylinder 1 is mounted on the rod end 7, and a compression-side oil passage 9 (see FIG. 2) and an extension-side oil passage 10 are formed in the piston 8.
A compression-side valve 11 for opening and closing the compression-side oil passage 9 and an extension-side valve 12 for opening and closing the extension-side oil passage 10 are attached.

A bottom valve case 15 is provided at the bottom inside the cylinder 1, a bottom bolt 16 is screwed into the bottom valve case 15, and a bottom check valve seat 17 is mounted on the bottom bolt 16. A valve 2 for forming a compression-side oil passage 18 and an extension-side oil passage (not shown) in the bottom check valve seat 17 to open and close the compression-side oil passage 18
A valve 21 for opening and closing the 0 and extension side valves is mounted.

On the inner bottom of the cylinder 1, a free piston 22 slidingly contacting the inner peripheral surface of the cylinder 1 and the bottom cap 3 is provided below the bottom valve case 15 in order to compensate for a change in volume due to the forward and backward movement of the hollow rod 6. Are slidably fitted to define a gas chamber SG.

A position detecting sleeve 25 made of a non-magnetic material is provided on the bottom bolt 16 so that the spherical end 25a is rotatable and movable in parallel, and the distal end of the position detecting sleeve 25 is placed in the rod end 7. A rod-like sensor having a rear end attached to the hollow rod 6 is inserted into the rod end 7, and a bush 26 slidingly contacting the outer peripheral surface of the position detecting sleeve 25 is fitted to the inner peripheral surface of the tip end of the rod end 7. Body 2
7 is inserted.

Further, a piston 8 is provided around the rod end 7.
A valve stopper 30 is fitted between the upper portion of the rod guide 4 and the rod guide 4. A bypass oil passage communicating the compression-side valve 11 becomes from the oil passage 32 formed in the oil passage 31 and the piston 8 is formed in the rod end 7 the outer peripheral direction by bypassing the compression-side oil passage 9 is provided, communicating with the bypass oil passage The orifice 33 to be formed is formed in the shaft portion 30a of the valve stopper 30 .

The flange 3 of the valve stopper 30
A plurality of conical grooves 35 are formed in the upper surface of Ob in the circumferential direction, and a plurality of conical grooves 36 are similarly formed in the circumferential direction inside the row of the conical grooves 35 in the circumferential direction. They are formed in the same manner to form two inner and outer rows of conical grooves. Both the row of the conical grooves 35 and the row of the conical grooves 36 are the conical grooves 35, 3
6 are formed at equal intervals, and the conical grooves 3 are formed at symmetrical positions.
A range where 5 and 36 are not formed (two portions are skipped in this case) is provided, and this range is defined as a dead zone.

The shaft portion 3 of the valve stopper 30
A select valve 37 is rotatably fitted on the outer peripheral surface of the spring 4a, and an engagement ball 39 engageable with the conical groove 35 outside the valve stopper 30 is mounted on the select valve 37 by a spring 4.
The engagement ball 4 which is urged at 0 and is engageable with the inner cone groove 36.
1 are biased by a spring 42 and provided at symmetrical positions.

Around the select valve 37, a plurality of orifices 43 having different diameters facing the orifice 33 of the valve stopper 30 are provided.
5, 36 are formed in the same direction as the radial direction.

A lock hole 44 is provided in the outer peripheral portion of the select valve 37 in the axial direction in the same phase as the conical grooves 35 and 36 in the axial direction.
Is formed. A push rod 45 that can be inserted into the locking hole 44 of the select valve 37 is inserted into the rod guide 4 so as to be vertically movable.

In the hydraulic shock absorber constructed as described above, when the hollow rod 6 moves down during the compression stroke, the hydraulic oil in the oil chamber S1 flows into the compression side oil passage 9 and the compression side valve 11 And flows into the oil chamber S2 to generate a damping force.
When the hollow rod 6 moves upward during the extension stroke, the oil chamber S
2 flows into the expansion side oil passage 10 and the expansion side valve 1
2 is depressed and flows into the oil chamber S1 to generate a damping force.

[0019] In this case, the compression of the piston 8 in the compression stroke
A part of the hydraulic oil that has flowed into the side oil passage 9 is the oil passage 32, the oil passage 31 of the rod end 7, and the orifice 3 of the valve stopper 30.
3 and selected orifice 43 of select valve 37
And flows into the oil chamber S2 by bypassing the extension side valve 12 through a bypass oil passage composed of: Therefore, by selecting the orifice 43 of the select valve 37, the opening amount of the bypass oil passage can be changed, and the damping force can be adjusted.

Here, when adjusting the damping force by selecting the orifice 43 of the select valve 37, the push rod 45 is pushed down and the locking hole 44 of the select valve 37 is pressed.
By rotating the hollow rod 6, the valve stopper 30 fitted to the rod end 7 is rotated in a state where the select valve 37 is not rotatable, and the orifice 33 of the select valve 37 is opposed to the orifice 43 of the select valve 37. To change.

In this case, the engagement balls 39, 41 provided on the select valve 37 are connected to the conical grooves 35, 3 of the valve stopper 30.
By engaging with 6, the moderation feeling is obtained, and the position of the damping force can be recognized by hand. Since the two engagement balls 39 and 41 are provided at symmetrical positions on the select valve 37, a greater sense of moderation can be obtained, and the reaction force of the springs 40 and 42 can reduce the symmetrical position of the select valve 37. , The feeling of stiffness is reduced, and the variation in damping force is also reduced.

[0022]

[Effects of the Invention] As described above, according to the present invention,
Two engaging balls each urged by a spring are provided at the other member at symmetric positions, and two rows of conical grooves in which the engaging balls can engage are formed in two rows in the circumferential direction of one member. The rows are provided with blind areas at symmetrical positions, improving the sense of moderation. The other member receives the spring reaction force at the symmetrical positions, reducing the sense of stiffness and the variation in damping force. Also decreases.

[Brief description of the drawings]

FIG. 1 is a sectional view of a hydraulic shock absorber to which a detent mechanism according to the present invention is applied.

FIG. 2 is an enlarged sectional view of a main part of FIG. 1;

FIG. 3 is a plan view of a valve stopper.

FIG. 4 is a sectional view taken along line AA of FIG. 3;

FIG. 5 is a bottom view of the select valve.

FIG. 6 is a sectional view taken along the line BB of FIG. 5;

FIG. 7 is a sectional view taken along the line CC of FIG. 5;

FIG. 8 is a plan view of a select valve.

[Explanation of symbols]

1 ... cylinder, 4 ... rod guide, 6 ... hollow rod, 7
... rod end, 8 ... piston, 9 ... compression side oil passage, 10
... extension side oil passage, 11 ... compression side valve, 12 ... extension side valve, 30 ... valve stopper, 31, 32 ... bypass oil passage, 33, 43 ... orifice, 35, 36 ... cone groove, 3
7 ... select valve, 39, 41 ... engagement ball, 40, 42
… Spring, 44… locking hole, 45… bush rod.

Claims (2)

(57) [Scope of request for utility model registration] 1. A plurality of conical grooves are formed in a circumferential direction of one member of a pair of members arranged so as to be relatively rotatable by providing a dead zone, and a circle of the one member is formed on the other member. In a detent mechanism of a hydraulic shock absorber in which an engagement ball engageable with a weight groove is disposed by being urged by a spring, a plurality of weight grooves are formed in two rows in the circumferential direction on the one member. In each row, a blind area is provided at a symmetrical position, and two engaging balls engageable with the conical grooves of each row are biased by a spring on the other member, and are arranged at the symmetrical positions. A detent mechanism for a hydraulic shock absorber characterized by being provided. 2. The one member is a valve stopper, and the other member is a select valve rotatably fitted to the valve stopper. The select valve has a diameter in phase with a conical groove of the valve stopper. 2. The detent mechanism for a hydraulic shock absorber according to claim 1, wherein an orifice having a different shape is formed.