JPH08210417A - Shock absorber - Google Patents

Abstract

(57) [Abstract] [Purpose] A spring can be reliably and stably supported by a spring bearing member having a simple and inexpensive structure without using an expensive spring bearing member with a collar as in the past. [Structure] Locking protrusion 3 provided on the outer periphery of cylinder 1
And a washer 7 and a washer 7 in the form of a ring plate that constitutes the first spring receiving member 5 and the second spring receiving member 6 on the cylinder 1 side and supports one end of the spring 4.
A cylindrical cover 8 mounted on the cylinder cover 8 and a cam surface 9b provided in the cylindrical cover 8 and slidably abutting on the locking projection 3 on one end surface thereof. A cylindrical cam member 9 having an inner diameter dimension that is inserted into the outer periphery of the
And the projections 8a and 9a projecting from the respective ends of the tubular cam member 9 and the tubular cover 8 are fitted into the notches 7a and 7b formed in the inner peripheral portion of the washer 7. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorber used as a rear cushion unit for a rear wheel suspension system of a motorcycle.

[0002]

2. Description of the Related Art As a conventional rear cushion unit, for example, there is one disclosed in Japanese Patent Laid-Open No. 61-140634.

In this, a damper is installed between a body frame and a rear arm that is pivotally supported by the body frame and supports a rear wheel, and a spring bearing member is attached to each end of the damper to extend the damper. As described above, a spring is interposed between the spring receiving members.

Further, in this rear cushion unit, the spring receiving member is moved in the axial direction of the damper by rotating one of the spring receiving members so that the initial repulsive force of the spring is made variable. And one end of the damper are engaged with each other by a cam means, and a cylindrical cover is provided on the spring receiving member so as to cover the cam means.

Further, the cam means is composed of a projection provided on the outer peripheral surface of the damper and a cam surface formed on the cover side and engaging with one end of the projection in the axial direction of the damper. Along with the formation of multiple openings along the edge, the other end of the protrusion can be seen through this opening, and the display body that displays the initial repulsive force of the spring at this time corresponds to each opening on the outer surface of the cover. It is attached to the position.

Further, in this rear cushion unit, the spring is assembled after the damper body is assembled.
Insert the spring force adjusting member and the spring into the damper body, and press the winding part other than the upper end of the spring downward with a finger to make a gap with the cover.

Next, a spring guide having a slit having a width that allows the piston rod to pass through is fitted into the upper surface of the spring, and in this state, the pressing force of the spring is gradually relaxed so that it is between the cover and the cover. The spring is assembled so that the spring guide is fitted.

[0008]

However, in such a conventional rear cushion unit, since the spring bearing member has a function of guiding the inner diameter of the spring, this spring bearing member is only for the reason of cost reduction and weight reduction. There was a problem in that it could not be immediately disused.

On the other hand, the cam member is provided with a flange portion on the spring side, which forms a flange on the pipe material to cut and form the cam surface, or a material punched out from a plate material is bent and ejected. Although it is formed, it is difficult to form the cam surface with the pipe material, the production efficiency is extremely poor, and it is disadvantageous in cost.In addition, if the punching step is required, the process becomes complicated and the cost is increased. There were problems such as being inevitable.

Further, the cover and the cam member are combined and joined together for transmitting the rotational force, and the above-mentioned joining is carried out after the cam of the cam member and the opening of the cover or the display body are aligned. There was a problem that it was necessary to perform alignment with a special jig because it was necessary.

The present invention has been made by paying attention to the above-mentioned conventional problems, and does not use an expensive spring receiving member with a collar as in the prior art, but a tubular cam for a washer. An object of the present invention is to provide a shock absorber capable of reliably and stably supporting a spring by a spring receiving member having a simple and inexpensive structure in which a member and a tubular cover are assembled.

Another object of the present invention is to provide a cushioning member that can be used as a spring support member for stably supporting the extension of the cylindrical cam member on the inner circumference of the spring.

Another object of the present invention is to provide a cushioning member which can facilitate the rotating operation of the cylindrical cover.

[0014]

According to a first aspect of the present invention, there is provided a shock absorbing device including a first spring receiving member and a second spring receiving member respectively provided on a cylinder and a piston rod which are expanded and contracted to absorb impact. A member, a locking projection protruding from the outer periphery of the cylinder, and a spring interposed between the first spring receiving member and the second spring receiving member for urging the cylinder and the piston rod in the extension direction. A ring plate-shaped washer that constitutes the first spring receiving member on the cylinder side and supports one end of the spring, a tubular cover attached to the washer, and one end face provided in the tubular cover. A cylindrical cam member having a cam surface slidably abutting on the locking projection and having an inner diameter dimension that is inserted into the outer periphery of the cylinder. A protrusion protruding from the respective end of the cylindrical cover is obtained so as to fit held in the notches formed in the inner peripheral portion of the washer.

According to a second aspect of the present invention, in the shock absorbing device, the tubular cam member extends through the notch of the washer at the portion opposite to the cam surface side and extends toward the spring side.

According to a third aspect of the present invention, there is provided a shock absorber having a cylindrical cover having a plurality of openings for rotating the cover.

[0017]

In the shock absorber according to the invention of claim 1, each of the tubular cam member and the tubular cover formed by punching out from a plate material and bending it into a tubular shape in a notch formed in the inner periphery of the washer supporting one end of the spring. By fitting the protruding part provided at the end,
A so-called flanged spring bearing member can be easily assembled with a simple and inexpensive structure.

Further, in the shock absorbing device according to the invention of claim 2, the extended portion of the tubular cam member stably supports the inner circumference of the spring whose one end is supported by the washer, and reliably prevents axial displacement of the spring. .

Further, in the shock absorber according to the third aspect of the present invention, the jig is locked in the opening provided in the tubular cover so that the tubular cover can be smoothly rotated on the cylinder. The locking position of the locking projection on the cylinder with respect to the cam surface of the cylindrical cam member can be arbitrarily set.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will now be described with reference to the drawings. FIGS. 1 and 2 are front views showing the entire shock absorber of the present invention in a partially cutaway view, and FIG. -A sectional view taken along the line A, in which 11 and 12 are a cylinder and a piston that expand and contract to absorb shock, and these constitute a shock absorber as a damper.

A projecting member 3 is provided on the outer periphery near the end of the cylinder 1.

The cylinder 1 and the piston rod 2 are mounted, for example, between a body frame of a two-wheeled vehicle and a rear arm end that is pivotally supported by the body frame and supports a rear wheel. Cylinder 1
A second spring bearing member 6 which supports one end of a spring 4 interposed between the first spring bearing member 5 on the side and the first spring bearing member 5 is attached.

Further, 7 is a ring plate-shaped washer as shown in FIGS. 3 and 4, and one end of a cylindrical cover 8 is attached to one side of the washer 7, and this cylindrical cover 8 A cylindrical cam member 9 is in contact with the inner peripheral base of the.

Here, a pair of protrusions 8a and two pairs of protrusions 9a are provided at one end of each of the cylindrical cover 8 and the cylindrical cam member 9 so as to project therefrom.
a is locked so as not to rotate in each of the two large and small notches 7a and 7b formed in the inner peripheral portion of the washer 7, and the protrusion 8a does not rotate in each of the two notches 7a. It is locked.

The protrusion 9a has the cutout 9a.
As shown in FIG. 1, it extends toward the spring 4 side, and this extended portion can support the inner circumference of one end of the spring 4.

Further, the protruding portion 9 of the tubular cam member 9
A cam surface 9b having a waveform that changes the distance from the surface of the washer 7 is formed on the end surface of the side a opposite to the protruding side, as shown in the development view of FIG.

As shown in FIGS. 1 and 2, the cam surface 9b faces the middle of the length of the cylindrical cover 8 and receives the elastic force of the spring 4 on the cam surface 9b. The tip of the protruding member 3 is locked.

On the other hand, the cylindrical cover 8 allows the positions of the protrusion members 3 to be described later to be seen from the outside at a plurality of positions facing the cam surface 9b of the cylindrical cam member 9. The cover 8 has a through hole 8b as shown in FIG. 6 for rotating the cover 8 with a jig.

The washer 7, the tubular cover 8 and the tubular cam member 9 constitute the first spring receiving member 5, and the tubular cover 8 and the tubular cam member 9 are formed by punching a plate material. After that, it is bent and formed into a tubular shape as described above.

Then, the washer 7 can be moved in the axial direction of the cylinder 1 by adjusting the contact position of the projection member 3 with respect to the cam surface 9b on the tubular cam member 9 by rotating the tubular cover 8. This makes it possible to adjust the initial repulsive force of the spring.

Therefore, in the shock absorber having such a structure,
At all times, the washer 7 receives the repulsive force of the spring 4 and urges the tubular cover 8 forming the first spring receiving member 5 together with the tubular cam member 9 to the left in FIG. The protruding member 3 on the outer periphery of the cylinder 1 is in contact with one of the cam surfaces 9b of the cylinder 9.

Here, when adjusting the initial repulsive force of the spring, a jig is inserted into the opening 8b of the cylindrical cover 8 and the cylindrical cover 8 is forcibly rotated on the cylinder 1. Manipulate.

By doing so, the cam surface 9b of the cylindrical cam member 9 is also rotated together with the cylindrical cover 8, and the contact position of the cam surface 9b with respect to the projection member 3 is adjusted.

As a result, the first spring receiving member 5 is moved by an amount corresponding to the contact position of the protruding member 3 with respect to the cam surface 9b.
Is displaced in the axial direction of the cylinder 1, and the initial repulsive force of the spring 4 can be adjusted.

The projection 9a of the cylindrical cam member 9 is also provided.
Extends through the notches 7a and 7b of the washer 7 and is greatly extended toward the spring 4 side. Therefore, the extended portion can stably support the inner circumference of the spring without axial displacement. The initial repulsive force setting value of can be maintained with high accuracy.

In the above embodiment, the protrusion 9a of the tubular cam member 9 has a length that penetrates the notches 7a and 7b of the washer 7, but as shown in FIGS. Like the protrusion 8a, the length may be set within the notches 7a and 7b.

Such a structure is effective when adopted when the winding diameter of the spring 4 is substantially the same as the outer diameter of the cylinder 1 and the outer circumference of the cylinder 1 can support the inner circumference of the spring 4.

Further, FIGS. 10 and 11 show the washer 7
In the figure, three large and small cutouts 7a and 7b are provided respectively. In this case, the large cutouts 7a and the small cutouts 7a and the small cutouts 7b are engaged with the large cutouts 7a. Six protrusions 9 at the end of the tubular cam member 9 are provided in the notch 7b.
a is engaged.

That is, two kinds of notches 7 of an appropriately selected number are formed on the respective projections 8a, 9a in a number corresponding to the required coupling strength of the washer 7, the tubular cam member 9 and the tubular cover 8.
It can be arbitrarily inserted into and engaged with a and 7b.

[0040]

As described above, according to the first aspect of the present invention, the first spring receiving member and the second spring receiving member provided on each of the cylinder and the piston rod that expand and contract to absorb impact. A spring that is interposed between the locking projection that is provided on the outer periphery of the cylinder and the first spring receiving member and the second spring receiving member to urge the cylinder and the piston rod in the extension direction. A ring plate-shaped washer for supporting one end of the spring, a tubular cover attached to the washer, and the first spring receiving member on the cylinder side; A cam surface slidably abutting on the locking projection is formed on one end surface, and a cylindrical cam member having an inner diameter dimension that is inserted into the outer circumference of the cylinder is provided.
Since the projecting portion projecting from each end of the tubular cam member and the tubular cover is fitted into the notch formed in the inner peripheral portion of the washer, an expensive brim like the conventional one is provided. The spring receiving member of simple and inexpensive construction in which the tubular cam member and the guide tube for the washer are assembled without using the spring receiving member described above has the effect of reliably and stably supporting the spring. is there.

According to the second aspect of the present invention, the tubular cam member is configured such that the portion on the side opposite to the cam surface side extends through the notch of the washer and extends to the spring side. There is an effect that the extension of the cam member can be used as a spring support member for stably supporting the inner circumference of the spring.

Further, according to the invention of claim 3, since the cylindrical cover is formed with a plurality of openings for rotating the cylindrical cover, a jig is used to adjust the initial repulsive force of the spring. For this reason, there is an effect that it is possible to obtain one that can facilitate the rotation operation of the cylindrical cover for.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view of a shock absorber according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view taken along the line AA of FIG.

3 is a cross-sectional view showing a first spring receiving member in FIG.

FIG. 4 is a left side view of the first spring bearing member shown in FIG.

5 is a development view showing the tubular cam member shown in FIG. 3. FIG.

6 is a development view showing the cylindrical cover in FIG. 3. FIG.

FIG. 7 is a sectional view showing another embodiment of the first spring bearing member of the present invention.

8 is a left side view of the first spring bearing member shown in FIG. 7. FIG.

FIG. 9 is a sectional view showing still another embodiment of the first spring receiving member of the present invention.

10 is a left side view of the first spring receiving member shown in FIG. 9. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylinder 2 Piston rod 3 Locking protrusion 4 Spring 5 First spring receiving member 6 Second spring receiving member 7 Washers 7a, 7b Notch 8 Cylindrical cover 8a, 9a Projection 8b Opening 9 Cylindrical cam member 9b Cam surface

Front Page Continuation (72) Inventor Toshihiro Yamada 2-4-1 Hamamatsucho, Minato-ku, Tokyo World Trade Center Building Kayaba Industry Co., Ltd. (72) Inventor Yasushi Ishii 2-4-1, Hamamatsucho, Minato-ku, Tokyo No. World Trade Center Building, Kayaba Industry Co., Ltd. (72) Inventor, Tadashi Shiro, 2-4-1, Hamamatsucho, Minato-ku, Tokyo World Trade Center Building Kayaba Industry Co., Ltd. (72) Inventor Shinichi Nishida Minato-ku, Tokyo 2-4-1 Hamamatsucho World Trade Center Building Kayaba Industry Co., Ltd.

Claims (3)

[Claims] 1. A first spring receiving member and a second spring receiving member respectively provided on a cylinder and a piston rod that expand and contract to absorb impact, and a locking projection provided on the outer periphery of the cylinder. And a spring interposed between the first spring receiving member and the second spring receiving member for urging the cylinder and the piston rod in the extending direction, and the first spring receiving member on the cylinder side. A ring-plate-shaped washer for supporting one end of the spring, a tubular cover attached to the washer, and a cam surface provided in the tubular cover and slidably abutting one end face of the locking projection. And a cylindrical cam member having an inner diameter dimension that is inserted into the outer periphery of the cylinder, and the projection formed at each end of the cylindrical cam member and the cylindrical cover is provided with the washer. A shock absorber characterized by being fitted and held in a notch formed in an inner peripheral portion of the charger. 2. The shock absorbing device according to claim 1, wherein the tubular cam member has a portion opposite to the cam surface side extending through the notch of the washer and extending toward the spring side. 3. The shock absorber according to claim 1, wherein the tubular cover is formed with a plurality of openings for rotating the tubular cover.