JPH09193869A - Shock absorber frame for bicycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To freely adjust the stroke range of a suspension, by rotatably connecting and joining one end of a chain stay, constituting a rear wheel swinging body, to a lower pipe, and also rotatably retaining one end of a back fork to a seat rag via a link mechanism. SOLUTION: A back fork 30 and a chain stay 28 are nearly V-shapedly constituted via a rear wheel gear 29, to form a rear wheel swinging body 27. The swinging body 27 rotatably connects and joins one end of the chain stay 28 to a lower pipe 26, and also rotatably retains one end of the back fork 30 to part of a seat rag 22 via a triangular link mechanism 34. The link mechanism 34, wherein one side is shortened to be adopted as a short side, forms pivotting parts 35 and 36 on both the corner parts of the short side, and also forms back fork fitting spindle holes 33a-33c of a back fork fitting part 33 on the apex angle parts. Consequently, a suspension stroke range can be freely adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a bicycle frame provided with a shock absorbing device, and more particularly, the shock absorbing power during traveling of the bicycle is further increased to further improve the riding feeling and to improve the riding comfort of the bicycle. An object of the present invention is to improve the running performance, durability, and safety by making it possible to adjust the road surface impact absorption range depending on the running road surface condition.

[0002]

2. Description of the Related Art With respect to the absorption of shocks caused by running a bicycle, most of the conventional devices have been designed so as to reduce the impact by bending the front fork. In the future, research has been conducted on a device that absorbs shocks, that incorporates a urethane reinforced resin in the head portion, or that has a suspension applied to the saddle itself.

However, the various suspensions described above
Both are shock absorption on the front wheel side or saddle part,
Not only has limited shock absorption capacity, but also has a shock absorption function on the rear wheel side, which is the most important in terms of riding feeling and functionality while driving, and there is no high rigidity, especially off The impact absorption capacity of the front and rear wheels required for road running was remarkably incomplete. With the realization of a lightweight frame material, finally, in the field of bicycle frames, a structure in which a suspension is incorporated into the frame itself through a link mechanism was developed by the inventors of the present invention, and the actual frame number is 6-175. Published as an issue.

As shown in FIG. 2, an upright pipe 4, an upper pipe 5 and a lower pipe 6 are interposed between the hanger lug 1 and the seat lug 2 and the head lug 3, and a chain stay 7 and A bicycle frame is constructed by adding a back fork. The chain stay 7 has one end rotatably held by the hanger lug 1 by a shaft 9 and has a rear wheel bearing (rear fork end) 8 integrally attached to the other free end thereof. A back fork member 14 is rotatably attached via a shaft 8a.

Further, the triangular link 10 is composed of a long side a having the longest side, a middle side b having an intermediate length, and a short side c having the shortest side, and the long side a side is the shock absorber cylinder 11 side. Toward the (head lug side), the long / short side corner portion d where the long side a and the short side c intersect is rotatably supported by the shaft with respect to the seat lug 2. The shock absorber cylinder 11 constantly urges the cylinder rod 13 toward the outside (protruding tip direction) by a hydraulic cylinder 11a and a coil-shaped spring 11b arranged on the outside thereof, and at the same time, its base is The upper pipe 5 is rotatably held via a mounting member 12, and the tip of the cylinder rod 13 is further connected to the middle piece b and the short piece c of the triangular link 10 at the middle and short side corners f. Rotatably attached to the shaft.

The front end of the above-mentioned back fork member 14 is axially attached to the long / medium side corner portion e where the long side a and the middle side b intersect, so that when the rear wheel receives an impact, As shown by the chain line position in FIG. 2, the chain stay 7 moves upward, and the long side and the middle side corner portion e of the triangular link 10 become long.
Cylinder rod 1 that is rotated clockwise around the short side corner portion d in the figure and is also connected to the middle / short side angle f
The shock is absorbed by pushing 3 into the shock absorber cylinder 11 against its outward biasing force.

In this case, the cylinder rod 1
The pressing torque received by 3 will be described. When the rear wheel receives an impact, the chain stay 7 moves counterclockwise in the figure with the shaft 9 of the holding portion of the hanger lug 1 as a fulcrum as the rear wheel bearing 8 moves. When it rotates (see the position indicated by the chain line in FIG. 2), the rear wheel bearing 8 part jumps up. At this time, the back fork member 14 follows this and the triangular link 10
Shock absorber cylinder 1
When pressed in one direction, the triangular link 10 will move the seat lug 2
With respect to the support portion (corner d of the long and short sides) as a center, the corner e of the long and middle sides is moved toward the shock absorber cylinder 11 against the pressing force of the cylinder rod 13.

Accordingly, the long side a, the middle side b, the short side c
However, as a result of each movement, the middle and short side corners f also move sequentially, and along with the movement of the middle and short side corners f, the cylinder rod 13 is pressed along the central axis of the cylinder rod, and the shock absorber cylinder Squeeze eleven gradually. At this time, the line connecting the long / middle side corner portion e and the seat lug fulcrum portion (long / short side corner portion d) and the back fork member 14
The angle formed with the center line of the back-fork member 14 is substantially a right angle as shown by the solid line position in FIG. Therefore, the upward movement of the chain stay 7 is controlled by the so-called progressive effect, thereby maintaining the suspension and high rigidity.

[0009]

The above-described structure in which the suspension is incorporated in the frame itself has a relatively favorable road surface impact absorption capacity even in its actual use after that, and has been highly evaluated. Recently, especially with the remarkable spread of mountain biking (MTB),
Various races such as off-road and downhill driving became popular, and the need to absorb the impact of rough road running was pressed, and a better riding feeling was demanded, so the above suspension was incorporated. Even in the structure, since the swing radius of the rear wheel is relatively small due to the limit of the length of the chain stay that constitutes a part of the suspension, it is not possible to obtain a sufficient shock absorbing ability. There is a growing demand for improvement.

Not only that, but also with respect to the stroke range of the suspension that absorbs the shock of the frame, if this is increased, the shock absorbing ability is improved in response to the relatively large unevenness of the road surface, but the riding feeling is improved. However, there is a problem in that it lacks agile and direct maneuvering performance when traveling on a comparatively gentle road surface, and is rather dissatisfied with respect to maneuverability.

[0011]

Therefore, the present invention is not only able to sufficiently meet the above-mentioned demands for weight reduction and high rigidity, but also has a large impact absorption capacity not seen in the above-mentioned suspensions. In addition to the above, we have developed an epoch-making suspension device that can freely adjust the stroke range of the suspension depending on the condition of the traveling road surface.

That is, the present invention is specifically about a hanger lug, a seat lug, and a head lug, which are connected to each other by a vertical pipe, an upper pipe, and a lower pipe, and a back fork and a chain which are located behind the frame. A rear wheel swing body integrally formed in a substantially V shape by coupling with a stay via a rear wheel bearing. One end of a chain stay constituting the rear wheel swing body is rotatable with respect to a lower pipe. The back fork has one end rotatably held by the seat lug through a link mechanism, and the link mechanism rotatably holds the base portion by the seat lug and shocks the middle portion. By connecting the cylinder rod of the absorber and always urging it toward the rear of the frame, further attach one end of the back fork to the tip. So attached to the shaft hole of the Zureka and relates to a bicycle shock absorber frame, characterized in that by forming a plurality of different back fork mounting shaft hole distance between the rear wheel axle.

When the rear wheel receives an impact on the road surface while the bicycle is traveling, a rear wheel swing body having a substantially V shape formed by coupling with the back fork and the chain stay rotatably fixes one end of the chain stay to the lower pipe. The rear wheel bearing portion that supports the rear wheel jumps upward with the fulcrum holding portion as a fulcrum. Along with this, the upper end of the back fork presses the cylinder rod of the shock absorber cylinder fixed to the upper pipe via the link mechanism to absorb the shock. That is, it has a so-called progressive effect in which the axle load changes in a curved shape with respect to the movement of the axle, whereby a sufficient suspension and high rigidity are maintained, and a traveling feeling without power loss is obtained.

Further, in this case, the mounting position of the back fork with respect to the link mechanism is usually attached to an intermediate shaft hole of the plurality of back fork mounting shaft holes depending on the road surface condition on which the vehicle is traveling, so that a comparatively gentle slope is obtained. When traveling on a rough road surface, in the shaft hole for mounting the back fork on the side where the distance to the rear wheel shaft becomes shorter,
On the other hand, when traveling on a considerably rough road surface, it is used by connecting it to the shaft hole for mounting the back fork, which has a longer distance from the rear wheel shaft.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The concrete contents of the present invention will be described below with reference to the embodiment shown in FIG.
Is a hanger lug, 22 is a seat lug, 23 is a head lug, 24 is a vertical pipe interposed between the hanger lug 21 and the seat lug 22, 25 is an upper pipe interposed between the seat lug 22 and the head lug 23, and 26 is a hanger. Each of the lower pipes interposed between the lug 21 and the head lug 23 is represented, and these constitute a so-called front triangular frame portion of the bicycle frame. Further, reference numeral 27 denotes a rear wheel swing body, which is a portion generally called a rear triangle. In this case, the back fork 30 and the chain stay 28 are formed in a substantially V shape through the rear wheel bearing 29. The rear wheel swing body 27 is formed.

Further, the rear wheel swing body 27 rotatably holds one end (lower end) of the chain stay 28 on the lower pipe 26. That is, at one end (lower end) of the chain stay 28, there is provided a holding portion 28a which is bent upward in a dogleg shape so as to avoid the bottom portion of the hanger lug 21 and follow the lower pipe 26, A fulcrum holding portion 28b at the tip of the holding portion 28a is rotatably attached to the lower pipe 26 via a fitting 31 by a pin 32. Further, one end (upper end) of the back fork 30 is rotatably held by a part of the seat lug 22 via a triangular link mechanism 34. That is, the link mechanism 34 has a substantially triangular shape as a whole, one side is shortened to be a short side, the shaft attachment portions 35.36 are formed at both corners of the short side, and the back fork is attached to the apex corner (tip). The part 33 is formed.

That is, the link mechanism 34 rotatably rotatably holds the shaft mounting portion 35 on the rear portion of the seat lug 22, and also mounts the intermediate shaft mounting portion 36 on the tip end of the cylinder rod 41 of the shock absorber cylinder 39. .
The shock absorber cylinder 39 includes a hydraulic cylinder 40 and a coil-shaped spring 42 arranged outside the hydraulic cylinder 40, and the cylinder rod 41 and the above-mentioned link mechanism 34 are supported by the shaft mounting portion 35 as a fulcrum.
In the state of, while always biasing counterclockwise,
One end of the base is rotatably held on the upper pipe 25 through a mounting bracket 37 and a mounting screw 38. Further, the back fork mounting portion 33 has a plurality of back fork mounting shaft holes 33a. 33b. 33c are formed.

FIG. 1 shows a state in which one end of the back fork 30 is axially attached to the back fork mounting shaft hole 33a having the shortest distance from the rear wheel shaft. 33a. 33b. 33
When the link mechanism 34 is at the position shown in FIG. 1, the shaft hole 33a has a rear wheel bearing 2c that is larger than the shaft hole 33b.
9 is the longest distance from the rear wheel axis P supported, and the shaft hole 33c is the shortest on the contrary. Therefore, when one end of the back fork 30 is pivotally attached to the shaft hole 33a of the link mechanism 34, the shock absorbing stroke range of the rear wheel swing body 27 is the smallest, and conversely when it is pivotally attached to the shaft hole 33c. Has the largest impact absorption stroke range of the rear wheel swing body 27.

The shaft attaching means in this case is not particularly limited, but for example, a general pin and one provided with a retaining means such as a screw at both ends thereof with a washer intervening. It is only necessary that the shaft attachment portion of the back fork 30 can be rotated with respect to the link mechanism 34, and that the structure can be relatively easily removed and attached.

With the above structure, the rear wheel (not shown) mounted on the rear wheel bearing 29 while the bicycle is running.
When a shock is applied to the rear wheel swing body 27,
Moves upward with the attachment pin 32 of the fulcrum holding portion 28b attached to the lower pipe 26 as the fulcrum, as shown by the chain line position in FIG.
The shock is absorbed by the hydraulic cylinder 40 and the coiled spring 42 via the suspension, thereby maintaining the suspension and high rigidity, and a traveling feeling without power loss is obtained.

Further, in this case, normally, when one end of the back fork 30 is used by being linked to the link mechanism 34 and the intermediate shaft hole 33b, and when traveling on a relatively flat road surface, It is used by being connected to the shaft hole 33a (state of FIG. 1). On the other hand, when traveling on a rough road surface with relatively large irregularities, it is used by being coupled to the shaft hole 33c.

[0022]

As described above, the present invention has a hanger lug, a seat lug, and a head lug as a center, and a frame in which these are connected by a vertical pipe, an upper pipe, and a lower pipe, and a back fork and a frame located behind the frame. A rear wheel swing body integrally formed in a substantially V shape through a rear wheel bearing by being connected to a chain stay, and one end of the chain stay constituting the rear wheel swing body is rotated with respect to the lower pipe. The back fork has one end rotatably held by the seat lug through a link mechanism, and the link mechanism holds the base rotatably by the seat lug and the middle portion of the seat lug. By connecting the cylinder rod of the shock absorber and constantly urging it toward the rear of the frame, the shaft for attaching the back fork at the tip Since one end of the back fork is connected to each other and the rear wheel swing body integrally formed in a substantially V shape, particularly the fulcrum holding portion of the chain stay is supported by the lower pipe, It is possible to exert a unique effect.

That is, the distance from the rear wheel bearing to the fulcrum holding portion of the chain stay is longer than that of a conventional hanger lug that is supported on the rear portion, and therefore the swing radius of the rear wheel swing body is increased, As a result, the movement of the rear wheels becomes more linear, and the impact resistance becomes significantly better,
It becomes easier to get over obstacles, and when the rear wheels are shocked while riding a bicycle, the impact absorption capacity is further increased to improve the riding feeling and improve the durability and running performance of the frame. As a result, a sufficient suspension and high rigidity can be maintained, a traveling feeling without power loss can be obtained, and traveling safety can be further improved.

Furthermore, in the case where one end of the back fork is connected to the tip of the link mechanism, the distance from the rear wheel shaft is set so that one end of the back fork is attached to the tip of the link mechanism in any shaft hole. Since a plurality of different back fork mounting shaft holes are formed, the mounting position of the back fork with respect to the link mechanism is usually mounted in the middle shaft hole of the plurality of back fork mounting shaft holes. In addition, when traveling on a comparatively gentle road surface, in the back fork mounting shaft hole where the distance to the rear wheel axle becomes shorter, and conversely, when traveling on a considerably rough road surface, Depending on the condition of the road surface on which the vehicle is traveling, such as when the rear wheel swing body is used by combining it with the shaft hole for mounting the back fork, which has a longer distance from the wheel axle, Stroke range for the shock absorbing (rear movement amount) can be adjusted freely, it is possible to obtain a more favorable traveling feeling.

[Brief description of the drawings]

FIG. 1 is a side view of a bicycle shock absorber frame showing an embodiment of the present invention.

FIG. 2 is a side view of a conventionally known bicycle frame.

[Explanation of symbols]

 21 Hanger Lug 22 Seat Lug 23 Head Lug 24 Vertical Pipe 25 Upper Pipe 26 Lower Pipe 27 Rear Wheel Swing 28 Chain Stay 28a Holding Part 28b Support Point Holding Part 29 Rear Wheel Bearing 30 Back Fork 31 Mounting Bracket 32 Pin 33 Back Fork Mounting Part 33a Back Shaft hole for fork mounting 33b Shaft hole for back fork mounting 33c Shaft hole for back fork mounting 34 Link mechanism 35 Shaft mounting portion 36 Shaft mounting portion 37 Mounting metal fitting 38 Mounting screw 39 Shock absorber cylinder 40 Hydraulic cylinder 41 Cylinder rod 42 Coiled Spring P Rear axle

Claims (2)

[Claims] 1. A hanger lug, a seat lug and a head lug as a center, and a frame in which these are connected by a vertical pipe, an upper pipe and a lower pipe, and a rear wheel shaft which is located behind the frame and which is connected to a back fork and a chain stay. A rear wheel swing body integrally formed in a substantially V shape via a receiver. One end of a chain stay constituting the rear wheel swing body is rotatably connected to a lower pipe and a back pipe is formed. One end of the fork is rotatably held by the seat lug via a link mechanism, and the link mechanism rotatably holds the base portion by the seat lug and connects the cylinder rod of the shock absorber to the intermediate portion. Always urge the frame toward the rear,
Further, a shock absorber for a bicycle, characterized in that a plurality of back fork mounting shaft holes having different distances from the rear wheel shaft are formed in order to attach one end of the back fork to one of the shaft holes at the tip portion. flame. 2. The mounting of the back fork into the plurality of back fork mounting holes formed at the tip of the link mechanism is configured to be replaceable in any of the plurality of back fork mounting holes. The shock absorber frame for a bicycle according to claim 1.