JPH06663Y2 - Hydraulic shock absorber - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a hydraulic pressure for a front fork or the like which is interposed between a vehicle body and an axle of a motorcycle and which serves as a shock absorber and a fork for damping vibrations from the road surface. Regarding the shock absorber.

[Conventional technology]

As a hydraulic shock absorber for such a conventional front fork, for example, the front fork shown in FIG. 4 has been developed.

In this front fork, the inner tube 2 on the axle side is slidably inserted into the outer tube 1 on the vehicle body side,
A damper cylinder 3 is provided in the lower center of the inner tube 2.
The piston rod 5 is movably inserted into the damper cylinder 3 via a piston incorporating a damping force generating mechanism, and an oil lock piece portion 21 is provided on the outer circumference of the piston rod 5. At the same time, the piston rod 5 is connected to a cap 6 provided on the outer tube 1.

Further, an upper oil hole rod 4 of the damper cylinder 3 is erected, a spring seat 7 is provided on the oil hole rod 4, and a suspension spring 8 is interposed between the spring seat 7 and the cap 6.

A spring guide 9 is vertically movably inserted between the inner circumference of the inner tube 2 and the outer circumference of the suspension spring 8, the upper end of the spring guide 9 is rotatably coupled to the cap 6, and the lower part of the inner tube 2 is Circumferential bearing 10
It slides via a bearing 11 on the outer periphery of the spring seat 7 and a bearing 12 on the lower end of the spring guide 9.

[Problems to be solved by the device]

In the conventional front fork described above, since the suspension spring 8 is provided with the spring guide 9, it is possible to prevent the suspension spring 8 from contacting or interfering with the inner peripheral surface or the tip portion of the inner tube 2, but the spring guide 9 is interlocked with the outer tube 1. Inner tube 2 for smooth vertical movement
Bearing 10 on the inner circumference of the tip and bearing 1 on the outer circumference of the spring seat 7
1 and the bearing 12 provided on the spring guide 9 itself are required.

For this reason, there are many bearings, friction during sliding increases, the smooth damping effect is impaired, and the structure is complicated and the cost increases.

Therefore, an object of the present invention is to provide a hydraulic shock absorber suitable for use with a front fork or the like, which does not require a spring guide or a plurality of bearings, does not generate friction, has a smooth damping effect, has a simple structure, and can reduce costs. Is to provide.

[Means for Solving the Problems]

In order to achieve the above object, the structure of the present invention is such that the inner tube is movably inserted into the outer tube, the damper cylinder is erected in the lower center of the inner tube, and the piston rod is inserted into the damper cylinder through the piston. It is inserted movably, the piston rod is connected to the outer tube, the suspension spring is interposed between the damper cylinder and the outer tube, and the lock fork is provided on the outer circumference of the piston rod. Insert a spacer on the upper periphery,
The lower end of the spacer is supported and fixed by the lock piece member, and the inner circumference of the suspension spring is guided along the outer circumference of the spacer along the axial direction.

[Action]

Even if the suspension spring vibrates or bends during expansion and contraction, the inner circumference of the suspension spring is guided along the spacer, which is a spring guide, so that it does not contact the inner tube. Since the spacer does not make sliding contact with the inner tube or outer tube, friction does not occur.

Further, since the spacers are fixed or an elastic body is interposed below the spacers, rattling between the spacers is prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIGS. 1 and 2, a hydraulic shock absorber such as a front fork according to the present invention includes an inner tube 2 connected to an axle side in an outer tube 1 connected to a vehicle body side.
The upper part of is inserted slidably.

A damper cylinder stands up in the center of the lower part of the inner tube 2, and a piston rod 5 is movably inserted into the damper cylinder via a piston having a damping force generating mechanism. Is connected to the outer tube 1 via.

A hollow oil hole rod 4 stands up on the top of the damper cylinder,
The spring seat 7 is connected to the upper portion of the oil hole rod 4,
A suspension spring 8 is interposed between the upper portion of the spring seat 7 and a spring seat 19 formed of a washer provided in the cap 6 to constantly urge the outer tube 1 in the extending direction.

A nut 15 and a holder 16 are fixed to the outer periphery of the piston rod 5 via a stopper 14 such as a snap ring, and the nut 15 and the holder 16 are screwed together. Holder 1
A lock piece 17 is movably fitted in a groove 20 formed on the outer periphery of the lock piece 6. The stopper 14, the nut 15, the holder 16 and the lock piece 17 constitute a lock piece member for oil lock. Therefore, at the time of compression operation, the lock piece 17 is fitted into the oil hole rod 4 near the time of maximum compression so that the cushion by the oil lock is effective.

A spacer 15 is inserted in the upper part of the outer periphery of the piston rod 5, and a supporting member 18 is provided in the lower part of the cap 6, and a spacer serving as a spring guide is provided between the supporting member 18 and the nut 15 constituting the lock piece member. 1
3 is held. That is, the lower end of the spacer 13 is supported by the lock piece member and is fixed so as not to move in the vertical direction.

The spacer 13 is located on the inner circumference side of the suspension spring 8, and the outer circumference of the spacer 13 supports the inner circumference of the suspension spring 8 along the axial direction. Therefore, the suspension spring 8
The radial bending, buckling, and swinging of the inner tube 2 are prevented, and the suspension spring 8 is prevented from coming into contact with the inner tube 2.

The spacer 13 is provided with a central portion for guiding the suspension spring 8 and tapered non-contact portions at the upper and lower ends, and the non-contact portion is cut to reduce the weight.

The spacer 13 may have a cylindrical cross section, or may have a plurality of radial ribs 13b provided on the outer periphery of the cylindrical base 13a as shown in FIG. When the ribs 13b are provided, there is no meat between the ribs, which reduces the weight and saves the material. In any case, the spacer 13 is not limited to the above-mentioned shape, and it is sufficient that the spacer 13 supports the suspension spring 8 along the axial direction. The spacer 13 does not make contact with the suspension spring 8, but may make light contact.

FIG. 3 shows another embodiment of the hydraulic shock absorber such as the front fork according to the present invention.

This embodiment is basically the same as the above-mentioned embodiment, but in this embodiment, a nut 15 and a holder 16 are further provided on the outer circumference of the piston rod 5 via a stopper 14 such as a snap ring. Is threadedly connected, and the lock piece 17 is movably fitted in the groove 20 provided on the outer periphery of the holder 16 between the nut 15 of the oil lock piece portion 21 and the lower end of the spacer 13 serving as the spring guide. An elastic body 22 composed of a ring or the like is interposed.

Therefore, in the present embodiment, it is of course possible to obtain the same actions and effects as those in the above-mentioned embodiment, and further, the elastic body 2
By interposing 2 between the spacer 13 and the oil lock piece portion 21, there is a backlash between the spacer 13 and the oil lock piece portion 21 caused by the accumulation of the dimensional tolerances of the spacer 13, the oil lock piece portion 21 and the like. To be prevented.

In this embodiment, the tip portion 2a of the inner tube 2 is formed in a tapered shape so that the suspension spring 8 is smoothly guided to the inner circumference of the inner tube 2.

[Effect of device]

 The present invention has the following effects.

Since the spacer is provided on the inner peripheral side of the suspension spring and guides the suspension spring along the axial direction, the suspension spring is prevented from being bent, buckled, or shaken in the radial direction. Are prevented from contacting the inner tube.

The spacer is provided on the inner peripheral side of the suspension spring and is separated from the inner tube. Therefore, the inner tube does not come into contact with anything other than the outer tube, so that the slidability is improved.

The lock piece member is fitted into the oil hole rod during compression to exert a cushion by the oil lock and has a spacer holding function. Therefore, no special means for fixing the spacer is required. Moreover, since the lower end of the spacer is supported and fixed by the lock piece member, the spacer is prevented from moving in the vertical direction, the sound is prevented, and the spacer is stable.

[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 cross-sectional plan view of another embodiment of a spacer, and FIG. 3 is another embodiment of the present invention. FIG. 4 is a partially cutaway vertical front view of the conventional hydraulic shock absorber, and FIG. 4 is a partially cutaway vertical front view of the conventional hydraulic shock absorber. [Description of symbols] 1 ... Outer tube 2 ... Inner tube 3 ... Damper cylinder 5 ... Piston rod 8 ... Suspension spring 13 ... Spacer 22 ... Elastic body 14 ... Stopper 15 ... Nut 16 ... Holder 17 ... Lock piece

Claims (1)

[Scope of utility model registration request] 1. An inner tube is movably inserted into an outer tube, a damper cylinder is erected in the lower center of the inner tube, and a piston rod is movably inserted into the damper cylinder through a piston. Connected to the outer tube, a suspension spring is interposed between the damper cylinder and the outer tube,
In a front fork in which a lock piece member is provided on the outer circumference of the piston rod, a spacer is inserted in the upper outer circumference of the piston rod, and the lower end of the spacer is supported and fixed by the lock piece member. A hydraulic shock absorber characterized in that the circumference is guided along the axial direction by the outer circumference of the spacer.