JPH1038005A - Spring constant adjusting device for suspension spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a spring constant adjusting part from being directly exposed to the duct environment to maintain its durability. SOLUTION: A spring guide 3 slidably provided on the outer periphery of a damper body 1, a main spring 2 interposed between the lower part of the damper body 1 and the spring guide 3, and a sub-spring 28 interposed between the spring guide 3 and the upper end part of a piston rod to elastically support the sub-spring 28, are provided to allow a compression stroke adjusting means to adjust the compression stroke of the sub-spring 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for adjusting a spring constant of a suspension spring, and more particularly to a suspension spring capable of switching a spring constant of a suspension spring in a hydraulic shock absorber as a rear suspension unit of a motorcycle. The improvement of the spring constant adjusting device.

[0002]

2. Description of the Related Art A suspension spring in a conventionally proposed hydraulic shock absorber as a rear suspension unit of a motorcycle is only interposed in a single state on the outer periphery of a damper body. The initial load can be adjusted by displacing the stop position in the vertical direction.

However, in such a conventional proposal, the initial load can be changed, but the spring constant itself cannot be changed. Therefore, the suspension weight of the suspension spring changes due to the change in the load weight on the suspension spring. It was not possible to cope with the change in the natural frequency, and therefore, there was a problem that the riding comfort of the motorcycle deteriorated.

In the above-mentioned conventional proposal, there is also a disadvantage that the operation torque in the rotation operation of the spring receiver is increased, and the adjustment operation is likely to be difficult.

On the other hand, as shown in FIG.
A main spring 42a disposed above a spring guide 44 in which the suspension spring 42 is rotatably and vertically movable on the outer periphery of the damper body 41, and a sub-spring disposed below the spring guide 44 42b, and a spring receiver 43, which is in contact with the lower end of the sub-spring 42b, is fixed to the outer periphery of the lower end of the damper body 41 so as not to be rotatable. There has been proposed an apparatus that can select whether compression is possible or not.

According to this, assuming that the rotation of the sub-spring 42b is adjusted to be compressible or non-compressible, the load-deflection characteristics of the suspension spring 42 are denoted by SM and M in FIG. The characteristics are as shown by.

[0007]

However, in such a conventional spring constant adjusting device for a suspension spring, the spring constant adjusting portion is exposed to the unsprung movement and vibrates violently, thereby deteriorating its durability. In addition to the occurrence of rattling and noise, there is a problem in that the cam adjuster is exposed to a dust environment because it is close to the road surface, thereby deteriorating the durability of the cam adjustment unit and the ride comfort.

In addition, a special tool is separately required to adjust the position of the spring guide 44, which increases the cost, requires a large operating force, and has extremely poor operability depending on the mounting position of the damper body. There was a problem of becoming.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a spring constant adjusting portion provided above a spring to adjust a change point of a spring constant and to initialize the spring constant. Adjustment is optional and easy.
In addition, a spring constant adjusting device for a suspension spring is provided which can be operated without requiring a large operating force and which can maintain the durability by preventing the spring constant adjusting portion from being directly exposed to a dust environment. That is.

[0010]

In order to achieve the above object, a spring constant adjusting device for a suspension spring according to the present invention is basically provided slidably on the outer periphery of a damper body. A spring guide, a main spring interposed between the lower part of the damper body and the spring guide,
A sub-spring is provided between the spring guide and the upper end of the piston rod to resiliently hold the piston rod, so that the compression stroke adjusting means adjusts the compression stroke of the sub-spring.

More specifically, a wheel gear for rotating the compression stroke adjusting means around the central axis of the piston rod by an external operation, and a wheel gear having an upper end portion and a stopper provided on the outer periphery are provided. It is assumed that the rotating cylinder and the cam are guided up and down by a stopper so that the cam surface is guided up and down and the gap with respect to the spring guide is adjusted.

In this case, it is assumed that the cam surface of the cam is urged by a return spring in the direction in contact with the stopper, or the cam surface is provided in an elongated hole formed in the cam in an inclined direction, The cam surface is guided by a stopper inserted therein.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. FIG. 1 is a partially cutaway front view showing a spring constant adjusting device of a suspension spring. In FIG. 1, reference numeral 1 denotes a damper body to which a lower end bracket (not shown) is attached to a lower side of a spring, and a lower spring receiver (not shown) is fixed to a lower portion of the damper body. The lower end of the main spring 2 which constitutes a part of the suspension spring S is supported.

Reference numeral 3 denotes a ring-shaped spring guide slidably fitted on the outer periphery of the upper portion of the damper main body 1, and the spring guide 3 is supported by the upper end of the main spring 2.

4 is a cylinder 1a of the damper body 1.
The bracket 5 at the upper end of the rod 4 can be attached to the upper side of the spring. 6 is a rod position regulating member which is attached to the upper end of the rod 4 and regulates the amount of the rod 4 entering the cylinder 1a.
Is a cap attached to the upper end of the rod 4 so as to cover the upper part and a part of the outer peripheral part of the rod position regulating member 6.

Reference numeral 8 denotes a cutout groove which is formed in the outer periphery of the cap 7 in a longitudinal direction, and is a part of a gear case 9 provided on the outer periphery of the cap 7 so as to cover a part thereof. A dovetail piece 9a is fitted in the cutout groove 8.

Reference numeral 10 denotes a stopper member attached to the center hole of the gear case 9, which is a snap ring 11.
Is held on the outer periphery of the cap 7. 12 is
The dust cover is attached so as to cover a part of the stopper member 10 and a corner of the cap 7.

As shown in FIG. 2, an operation shaft 13 penetrates the gear case 9 in and out.
A worm gear 14 is attached to the end of the operation shaft 13 inside the worm gear.
A wheel gear 15 rotatably arranged around the cap 7 facing the inside is engaged.

In a notch 15a provided in the wheel gear 15, a rotary cylinder 1 covering the outer peripheral portion of the rod 4 is provided.
6, a claw piece 16a protruding from the upper end is fitted and fixed. Reference numeral 17 denotes a resin washer attached to the inside of the gear case 9 and slidably in contact with the wheel gear 15 and the upper end surface of the rotary cylinder 16.

Reference numeral 18 denotes a stopper protruding from the outer periphery of the rotary cylinder 16.
A cylindrical cam 19 which is slidable in the vertical direction while a cam surface 19a formed on the upper end edge contacts the stopper 18.
Is inserted.

Reference numeral 20 denotes a spring receiver mounted on the inner periphery of the lower end of the cam 19. A return spring 21 is interposed between the spring receiver 20 and the spring guide 3, and
The cam surface 19 a of the cam 19 is urged by the return spring 21 so as to lightly contact the lower surface of the stopper 18.

Reference numeral 22 denotes a rotation restricting member projecting so as to be screwed into a part of the cam 19. The rotation restricting member 22 is a guide cylinder 23 disposed on the outer peripheral side of the cam 19.
Can be moved up and down within the vertically elongated hole 24 formed at the maximum length of the elongated hole.

The guide tube 23 has a flange 23a fixed to the lower surface of a dust cover 25 closing the lower end opening of the gear case 9. The lower surface of the flange 23a has a cylindrical shape through a washer 26. The flange 27a at the upper end of the outer cover 27 is fixed.

The outer cover 27 has a length up to the vicinity of the spring guide 3, and another suspension spring S is formed between the flange portion 27 a of the outer cover 27 and the spring guide 3. Two sub-springs 2
8 are interposed.

Therefore, in the spring constant adjusting device of the suspension spring having such a configuration, the worm gear 14 and the wheel gear meshing therewith are first operated by rotating the operating shaft 13 from outside the gear case 9. Rotate 15

For this reason, the rotary cylinder 16 integrated with the wheel gear 15 horizontally rotates, and the stopper 18 which moves in the same direction with this rotation is provided on the cam surface of the cam 19 urged upward by the return spring 21. The cam 19 is moved up and down by a predetermined amount in any one of the upper and lower directions via 19a.

Then, the rotation regulating member 22 moves into the vertically long hole 24 of the guide cylinder 23 and stops by an amount corresponding to the amount of elevation. The gap G between the lower edge of the cam 19 and the spring guide 3 is a compression stroke region where the sub-spring 28 can be compressed.

Accordingly, the gap G is adjusted in accordance with the amount of adjustment of the cam 19, so that the break point in the characteristic indicated by the symbol SM in FIG. 7, that is, the break point of the spring constant of the entire suspension spring is changed. Will change.

Then, the lower end of the cam 19 is pressed against the spring guide 3 by the vertical adjustment of the cam 19 by the stopper 18 as described above, whereby the initial adjustment of the main spring 2 is made possible. Properties can also be obtained.

Further, by connecting the operating shaft 13 to the motor shaft and remotely controlling the motor, there is an advantage that the spring constant of the suspension spring can be easily and quickly adjusted by the driver.

Further, since the spring constant adjusting portion is provided on the upper side of the spring, it is not directly exposed to a violent vibration under the spring or a dust environment, so that significant deterioration of durability and deterioration of riding comfort can be effectively improved. The advantage is that the adjustment operation of the spring constant can be performed easily and smoothly even manually.

FIG. 3 shows another embodiment of the present invention, which is different from that shown in FIG. 1 in that a guide cylinder 23 for guiding the rotation regulating member 22 into a vertically long hole 24 is provided. It is located inside the rotary cylinder 16.
A sub-spring 28A smaller in diameter than that shown in FIG. 1 is interposed between the bent portion 23b at the upper part of the guide cylinder 23 and the spring guide 3.

The bent portion 23b of the guide tube 23 is connected to a ring-shaped bent tube 31 attached to the lower end of the cap 7.
It is fixed to the lower end by welding or the like. Reference numeral 32 denotes an O-ring interposed at a sliding contact portion between the bent cylinder 31 and the rotary cylinder 16 for preventing the guide cylinder 23 from falling off during assembly.

In this embodiment, the space between the rod 4 and the rotary cylinder 16 is used to make the sub-spring 28
By installing A, the sub-spring 28A
This has the advantage that the diameter can be reduced and the outer diameter of the entire apparatus can be reduced.

The stopper 18 as shown in FIG.
As shown in FIG. 5, a disc-shaped or column-shaped rotatable stopper 18A fixed to the rotary cylinder 16, this stopper 18A is formed on a part of the cam 19, and the lower edge is a cam surface. The cam surface 33 can be guided by the stopper 18A by being inserted into the elongated hole 34 formed in the inclined direction.

The width of the long hole 34 depends on the stopper 18A.
Are slightly larger than the outer diameter of In addition, the cam surface 33 is formed as a whole with a waveform of the same equal pitch, the stopper 18A is always stably supported in one of the concave portions, and when the spring constant is set, the rotating cylinder is operated by the motor or the manual operation. By rotating the rotary member 16, the position of the stopper 18A can be changed to any other concave portion.

In this embodiment, the return spring 21 as shown in FIG. 3 can be omitted, and the omission of the cam 19 can be prevented by the stopper 18A by this omission, and the rotation restricting member 22 restricts the rotation of the cam 19. Making it possible.

The position of the stopper 18 and the cam 19 may be reversed, and the rotation regulating member 22 may be arbitrarily provided on the cam, the stopper or the guide cylinder 23.

[0039]

As described above, according to the first aspect of the present invention, the spring guide slidably provided on the outer periphery of the damper main body and the spring guide interposed between the lower part of the damper main body and the spring guide. A main spring and a sub-spring interposed between the spring guide and the upper end of the piston rod to resiliently hold the piston rod are provided so that the compression stroke adjusting means adjusts the compression stroke of the sub-spring. With this configuration, the spring constant adjustment portion is installed on the upper side of the spring, so that the adjustment of the change point of the spring constant and the initial adjustment can be arbitrarily and easily performed, and the spring constant adjustment portion is directly exposed to the dust environment. In such a case, it is possible to obtain the effect that the durability can be maintained.

According to the second aspect of the present invention, the compression stroke adjusting means is externally operated to rotate the piston gear about the central axis of the piston rod, and the wheel gear is provided at the upper end and a stopper is provided on the outer periphery. It consists of a rotating cylinder provided and a cam that can be raised and lowered with the cam surface guided by the stopper and moved up and down and the gap to the spring guide is adjusted, so only a simple wheel gear rotation operation from the outside of the gear case The effect that the amount of compression of the sub-spring by raising and lowering the cam can be adjusted lightly and easily is obtained.

According to the third aspect of the present invention, the cam is urged by the return spring in the direction in which the cam surface of the cam comes into contact with the stopper. There is an effect that the transmission can be reliably performed.

According to the fourth aspect of the present invention, the cam surface is provided in an elongated hole formed in the cam in an inclined direction, and the cam surface is guided by a stopper inserted into the elongated hole. With this configuration, the return spring can be omitted, and the cam can be prevented from falling out of the rotary cylinder without the sub-spring.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a spring constant adjusting device of a suspension spring according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a main part of the spring constant adjusting device of the suspension spring shown in FIG.

FIG. 3 is a sectional view of a main part showing a spring constant adjusting device of a suspension spring according to another embodiment of the present invention.

FIG. 4 is a sectional view of a main part showing a modification of a part of the spring constant adjusting device of the suspension spring shown in FIG. 3;

FIG. 5 is a front view of the modification shown in FIG.

FIG. 6 is a cross-sectional view showing a part of a conventional spring constant adjusting device for a suspension spring.

FIG. 7 is a load-bending characteristic diagram of the suspension-constant spring constant adjusting device shown in FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Damper main body 2 Main spring 3 Spring guide 4 Rod 15 Wheel gear 16 Rotating cylinder 18, 18A Stopper 19 Cam 19a Cam surface 21 Return spring 28 Subspring

Claims (4)

[Claims] A spring guide slidably provided on an outer periphery of the damper body, a main spring interposed between a lower part of the damper body and the spring guide, and a spring guide and an upper end of the piston rod. And a compression stroke adjusting device for adjusting a compression stroke of the sub-spring. 2. A wheel gear whose compression stroke adjusting means rotates about a central axis of a piston rod by an external operation, a rotary cylinder having the wheel gear at an upper end and a stopper provided on an outer periphery, 2. A spring constant adjusting device for a suspension spring according to claim 1, further comprising a vertically movable cam whose cam surface is guided to ascend and descend and adjust a gap with respect to a spring guide. 3. The spring constant adjusting device for a suspension spring according to claim 2, wherein the cam surface of the cam is urged by a return spring in a direction in contact with the stopper. 4. The cam surface is provided in an elongated hole formed in the cam in an inclined direction, and the cam surface in the elongated hole is guided by a stopper inserted into the elongated hole. A spring constant adjusting device for a suspension spring according to claim 2.