JPH0744833Y2 - Spring load adjusting device for hydraulic shock absorber - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention is for use in a front fork that doubles as a shock absorber and a fork that is interposed between the vehicle body side and the wheel side of a motorcycle and damps vibrations from the road surface. A suitable hydraulic shock absorber spring load adjustment device.

[Prior Art] As a conventional front fork of this type, for example, FIG.
The one shown in FIG. 5 is known.

In the front fork shown in FIG. 4, an inner tube, which is a wheel-side tube 2, is slidably fitted in an outer tube, which is a vehicle-side tube 1, and a damper cylinder 3 stands up from the lower center of the wheel-side tube 2, and a damper cylinder 3 A piston rod 4 is movably inserted therein through a piston 5, and a suspension spring 6 is interposed between an upper portion of a vehicle body side tube 1 and an upper portion of a damper cylinder 3 so that the vehicle body side tube 1 and the piston rod 4 are always maintained. It is urged in the stretching direction.

The front fork in FIG. 5 uses an inner tube as the vehicle body side tube 7 and an outer tube as the wheel side tube 8, and the other structures are the same as those in FIG.

The spring load of the suspension spring 6 shown in FIGS. 4 and 5 is achieved by the structure shown in FIG.

That is, the cap 9 is connected to the upper end of the vehicle body side tube 1 or 7, the adjusting rod 10 is screwed into the center of the cap 9 so as to be movable in the axial and rotational directions, and the upper part of the piston rod 4 is attached to the lower center of the adjusting rod 10. The lower part of the adjusting rod 10 carries the upper part of the suspension spring 6 via the washer 11 and the spacer 12, and when the adjusting rod 10 is moved in the axial direction while rotating, the washer 11 and the spacer 12 move in the axial direction. The suspension spring 6 is expanded and contracted to set its initials.

[Problems to be Solved by the Invention] In the above spring load adjustment, the piston rod 4 is an adjustment rod.
Since it is screwed with 10, the piston rod 4 and the piston 5 also move up and down as the adjusting rod 10 moves up and down, and it is necessary to secure an extra damper side stroke by the amount of piston position change. Becomes long and uneconomical.

Further, the piston rod 4 is connected to the cap 9 through the adjusting rod 10, but the screw portion of the connecting means has some play, which causes a dead zone of the damping force, which deteriorates the riding comfort of the motorcycle.

Therefore, it is an object of the present invention to provide a spring load adjusting device for a hydraulic shock absorber, which can prevent the vertical movement of the adjusting rod from being transmitted to the piston rod and the piston, thereby preventing the damper cylinder from becoming longer and the dead zone of the damping force from occurring. is there.

[Means for Solving the Problems] In order to achieve the above object, the configuration of the present invention is such that the vehicle body side tube and the wheel side tube are slidably fitted together, and the damper cylinder is erected from the lower portion of the wheel side tube. In the above hydraulic shock absorber, a cap is screwed onto the upper part of the vehicle body side tube, and an adjustment rod is rotatably and axially movably connected to the central hollow part of the cap body. It consists of a body with a width across flats, the upper part of the piston rod is fixed to the center of the lower part of the body, and a radial through hole is formed in the middle of the body. Insert a washer that is movable in the axial direction, and bring the lower end of the adjustment rod into contact with the upper surface of the washer body,
The seat portion projecting from the outer periphery of the washer body is projected outward from the through hole, and the lower surface of the seat portion carries the upper part of the suspension spring directly or via a spacer.

[Operation] When the adjusting rod is rotated, the adjusting rod moves up and down via the screw, and this motion is transmitted to the suspension spring via the washer to expand and contract to set the initial, while the piston rod is set to the adjusting rod. The movement of the adjusting rod is not transmitted because it is far away. Since the washer is inserted in the body of the cap, it does not fall downward when the suspension spring is assembled.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention. A cap 13 is screwed onto the upper portion of the vehicle body side tube 1 or 7, and the cap 13 is composed of a main body 14 and a body portion 15 vertically provided at a lower portion of the center of the body 14 and penetrates in the center of the body portion 15 in a radial direction. Through hole 17
And the vertical surfaces 16, 16 facing each other on the outside are formed to form a two-sided width.

An adjusting rod 19 is rotatably and axially movably inserted into a screw hole 18 in the center of the cap body 14, and the diameter of the adjusting rod 19 is formed to be larger than the width between the vertical surfaces 16 and 16 of the cap body 15. A part of the adjustment rod 19 projects outward from the through hole 17, and the adjusting rod 19 can move along the axial width of the through hole 17 in the axial direction by the width thereof.

The upper part of the piston rod 4 is screwed into the screw hole 20 at the center of the lower part of the cap body 15, and is separated from the adjusting rod 19.

A washer 21 is vertically movably inserted into the hollow portion of the cap body portion 15. The washer 21 includes a main body 22, a hole 23 formed in the center of the main body 22, and a seat portion 2 protruding from the outer periphery of the main body 22.
It has 6,26.

As shown in FIG. 3, the washer 21 should be oriented vertically and should have a through hole.
It is inserted into the body 15 from 17 and then turns horizontally. At this time, the seat portion 26 projects outward from the through hole 17.

The piston rod 4 is inserted into the hole 23 of the washer 21 from above, and the lower surface of the adjustment rod 19 contacts the upper surface of the washer body 22.

A cylindrical spacer 24 abuts on the lower surface of the seat portion 26 of the washer 21, and an upper portion of the suspension spring 6 is carried on a lower portion of the spacer 24. However, the suspension spring 6 may be directly brought into contact with the lower surface of the seat portion 26 of the washer 21.

When adjusting rod 19 is rotated, cap body 14
The stroke of the through hole 17 can be the axial width of the through hole 17.

When the adjusting rod 19 moves up and down, the washer 21 and the spacer 24 move up and down in conjunction with each other, and the suspension spring 6 expands and contracts by the stroke, and the initial load is set. The initial load is arbitrarily adjusted according to the stroke of the adjusting rod 19.

At this time, the piston rod 4 does not change at all. still,
Reference numeral 27 is a nut for tightening the piston rod 4, and 28, 29 and 30 are passages that connect the inside of the damper cylinder and the oil chamber 31.

[Effect of the Invention] According to the present invention, the following effects can be obtained.

Since the adjusting rod and the piston rod are separated from each other and the movement of the adjusting rod is not transmitted to the piston rod, the positions of the piston rod and the piston do not change, and it is not necessary to take an extra stroke of the damper cylinder. Further, even if the adjusting rod is screwed and there is a play in the screw portion, the piston rod does not move and the dead zone of the damping force does not occur.

The adjusting rod can move up and down by the axial length of the through hole on the cap side, and the spring load of the suspension spring is adjusted according to this stroke.

The washer that supports the suspension spring is inserted into the body of the cap, and the seat only projects outward, so the washer does not drop below the cap when the suspension spring is assembled, improving the ease of assembly. To do.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view of a hydraulic shock absorber according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 shows an assembled state of a washer and an adjusting rod. FIG. 4 is a perspective view of the cap, FIG. 4 and FIG. 5 are schematic cross-sectional views of a conventional hydraulic shock absorber, and FIG. 6 is a partially longitudinal front view of the conventional hydraulic shock absorber. 1,7 …… Body side tube, 2,8 …… Wheel side tube, 3…
… Damper cylinder, 4 …… Piston rod, 6 …… Suspension spring, 14 …… Cap body, 15 …… Body part, 17 …… Through hole, 19 …… Adjustment rod, 21 …… Washer, 22 …… Seat part , 24 …… Spacer.

Claims (1)

[Scope of utility model registration request] 1. A hydraulic shock absorber in which a vehicle body side tube and a wheel side tube are slidably fitted together, and a damper cylinder is erected from a lower portion of the wheel side tube, and a cap is screwed onto an upper portion of the vehicle body side tube. The adjustment rod is rotatably and axially movably connected to the central hollow part of the cap, and the cap is composed of the main body and the body having a width across flats provided in the lower part of the body. The upper part of the piston rod is fixed, a radial through hole is formed in the middle of the body, and a washer that is movable in the axial direction is inserted into the body through this through hole. The lower end is abutted, and the seat portion protruding on the outer periphery of the washer body is projected outward from the through hole, so that the lower surface of the seat portion carries the upper portion of the suspension spring directly or through a spacer. Features Hydraulic shock absorber of the spring load adjusting apparatus.