JP2002293284A - Eccentric chain adjuster structure for motorcycles - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a stopper for an eccentric chain adjuster so that it is small, lightweight and versatile. A chain adjuster is provided in an axle holder provided at a rear end of a cantilevered rear swing arm.
Is rotatably supported, and penetrates an axle support portion 28 provided at an eccentric position of the chain adjuster 22 so that the rear wheel axle 8
Is rotatably supported. A driven sprocket is provided at one end of the rear wheel axle 8 so as to be integrally rotatable. A brake caliper bracket 38 is supported at the other end of the axle support portion 28, and a stopper 46 removably attached to a side surface of the chain adjuster 22 is attached to the brake caliper bracket 38 at a rotation restricting angle of the chain adjuster 22. Abut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an eccentric type chain adjuster used for adjusting a chain tension in a motorcycle. Here, the eccentric chain adjuster supports the rear wheel axle at an eccentric position and, by rotating itself, eccentrically rotates the rear wheel axle to change the supporting position back and forth. In the present invention, the front, rear, left, right, and upper and lower directions are based on the use state of the motorcycle, and the traveling direction of the motorcycle is defined as forward.

[0002]

2. Description of the Related Art An eccentric chain adjuster is provided on a cantilever type rear swing arm which supports a rear wheel at one rear end, and a rear wheel axle is passed through an eccentric position of the eccentric chain adjuster to rotate the eccentric chain adjuster. 2. Description of the Related Art An eccentric chain adjuster is known in which a rear wheel axle is eccentrically rotated to change its front-rear position and thereby adjust the axle length, thereby adjusting the chain tension.

[0003]

By the way, the adjustable rotation range of the eccentric chain adjuster has its rotation angle restricted so that it can be used within a predetermined range, and a stopper for this is provided on the rear swing arm. The chain adjuster rotated by a predetermined angle is brought into contact with the chain adjuster to restrict the rotation. However, if the stopper is provided integrally with the rear swing arm, if the size and shape of the rear swing arm and chain adjuster are changed, or if it is desired to change the rotation restriction angle, the design of the rear swing arm itself must be changed. Is required, so that versatility is poor. It is also conceivable to use a bolt as the projection, but in this case, the bolt must be protruded long to the rotation range of the chain adjuster. Therefore, a stopper that is versatile, relatively lightweight and small in size is desired, and the present invention aims to fulfill such a demand.

[0004]

According to a first aspect of the present invention, there is provided an eccentric type chain adjuster structure for a motorcycle, comprising: a rear swing arm; and a chain adjuster rotatably provided at a rear end. And a rear wheel axle supported at an eccentric position of the chain adjuster, and by rotating the chain adjuster, the rear wheel axle is eccentrically rotated to adjust the tension of the chain. A stopper is detachably provided on the chain adjuster, and the stopper abuts on a rear swing arm side member located near the stopper to restrict rotation of the chain adjuster beyond a predetermined range.

A second aspect of the present invention is characterized in that, in the first aspect, the stopper is a bolt. A third aspect of the present invention is also characterized in that, in the first aspect, the rear swing arm side member contacting the stopper is a brake caliper bracket or a torque rod for a brake which overlaps with a chain adjuster in a side view.

[0006]

According to the first aspect of the present invention, the stopper is provided on the side of the chain adjuster so that the stopper comes into contact with the rear swing arm side member when the chain adjuster is rotated. The rotation can be restricted to an angle. At this time, by providing the stopper on the chain adjuster side, even if the size, shape, etc. of the chain adjuster and the rear swing arm change, it can be dealt with by replacing the stopper itself or changing the mounting position each time, and the rear swing arm itself Design changes can be made unnecessary. Further, by changing the mounting position of the stopper, the rotation restricting angle can be arbitrarily changed.

Further, since it can be used for various chain adjusters and rear swing arms having different sizes and shapes, versatility is increased. In addition, the stopper protrudes from the chain adjuster side and comes into contact with the rear swing arm side member located in the vicinity,
The degree of freedom of the mounting position is increased as compared with the case of projecting from the rear swing arm, so that the amount of projection can be reduced and the size and weight can be reduced.

According to the second aspect of the present invention, the stopper can be detachably attached by using a bolt as the stopper, and the length of the protrusion can be freely adjusted.

According to the third aspect of the present invention, since the rear swing arm side member with which the stopper abuts is a brake caliper bracket or a brake torque rod which overlaps with the chain adjuster in a side view, the degree of freedom regarding the mounting position of the stopper is reduced. The contact can be made large and with a small amount of protrusion.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment will be described below with reference to the drawings. FIG. 1 is a left side view of a main part of a motorcycle to which the present embodiment is applied, FIG. 2 is an enlarged side view of a rear swing arm, FIG. 3 is a plan view thereof, and FIG. 5 is a right side view of the same, and FIG. 6 is a sectional view taken along line 6-6 of FIG.

First, in FIG. 1, the motorcycle is provided with a main frame 2 extending rearward from a head pipe 1, and an engine 3 is suspended and supported below the main frame 2. The engine 3 is a V-type four-cylinder engine,
A part of the body frame is formed together with the main frame 2 to form a diamond frame. The front end of a cantilevered rear swing arm 6 is swingably supported by a pivot shaft 5 on the left and right of the rear end of a pivot frame 4 provided on the left and right of the rear end of the engine 3.

A rear wheel 7 is supported at one rear end of the cantilevered rear swing arm 6, and a driven sprocket 9 is provided at one end of a rear wheel axle 8 located at the center thereof. A chain 11 is wound around the driven sprocket 9 and the drive sprocket 10 of the engine 3, and the rear wheel 7 is driven by the chain.

In the figure, reference numeral 12 denotes a front wheel, 13 denotes a front wheel axle,
14 is a front fork, 15 is a seat rail, 16 is a rear frame, 17 is a rear cushion, and 18 is a muffler.

As shown in FIGS. 2 and 3, the cantilever type rear swing arm 6 is obtained by casting a suitable service material such as a light alloy or the like, and pivot arms 20 are provided on the front left and right sides thereof, respectively. Of the engine 3 by the pivot shaft 5
Pivotally connected to the pivot frame 4.

At the rear end of the cantilever type rear swing arm 6, there is provided an axle holder 21 having a round hole penetrating in the left-right direction, and a substantially cylindrical chain adjuster 22 is provided in the axle holder 21. It is rotatably supported. The rear part of the axle holder 21 is divided into upper and lower parts, and the slit of this part reaches the rear end of the cantilever type rear swing arm 6, and the bolt 24 is tightened at the split tightening part 23 provided here. The chain adjuster 22 in the holder portion 21 is fixed so as not to rotate, and is loosened to be rotatable.

The chain adjuster 22 is a member formed by an appropriate method such as casting, and has an axle hole 25 penetrating right and left at the center thereof. The rear axle 8 inserted into the axle hole 25 is a needle. The rear wheel axle 8 is rotatably supported via a bearing 26 and a ball bearing 27. The hole diameter of the axle hole 25 changes in multiple stages so as to gradually decrease from the right side of the vehicle body (upper side in FIG. 3) to the left side (lower side in FIG. 3). A portion surrounding the axle hole 25 forms a substantially cylindrical axle support portion 28 integrally formed with the chain adjuster 22, and one end portion thereof forms a protruding portion 29 and protrudes to the right side of the vehicle body.

The rear wheel axle 8 penetrates the axle support portion 28 of the chain adjuster 22 and protrudes left and right, and the step gradually narrows from the upper side to the lower side in FIG. It is shaped like an axle, and can be inserted into and removed from the axle hole 25 from above (right side of the vehicle body).

A driven sprocket 9 is attached to an end of the rear wheel axle 8 protruding to the left side of the vehicle body by a bolt 31 and a nut 32 via a known damper 30 which is spline-coupled, and is transmitted from the chain 11 to the driven sprocket 9. The driving force is transmitted to the rear wheel axle 8 while being damped by the damper 30. The damper 30 is fixed by an axle nut 33 fastened to the tip of the rear wheel axle 8, and the rear wheel axle 8 itself is also prevented from coming off.

At the right end of the rear axle 8, a bolt 35 and a nut 36 are attached to a flange 34 formed integrally.
The brake disc 37 is attached. Further, a brake caliper bracket 38 is disposed between the brake disc 37 and the rear end of the cantilever type rear swing arm 6, and is fitted around a projecting portion 29 provided on the axle support portion 28 to be rotatable. And is secured by a clip 39.

As shown in FIG. 4, the brake caliper bracket 38 has a substantially V-shape when viewed from the side. A brake caliper (not shown) is attached to the tip of one arm portion 40, and the other arm portion 41 is cantilevered. Rear swing arm 6
The brake torque rod 43 is connected between the boss 42 provided on the side surface of the brake rod.

As shown in FIGS. 4 to 6, the axle support portion 28 forms a small-diameter cylindrical portion that rotatably fits and supports the rear wheel axle 8.
The center C1 is provided at an eccentric position having a dimension e from the center C2 of the chain adjuster 22. When the chain adjuster 22 rotates, the center C1 of the axle support portion 28, that is, the center of the rear wheel axle 8 rotates eccentrically. ing.

A stopper 46 is removably attached to a screw hole 45 (FIG. 6) formed in a relatively large area of a side surface 44 of the chain adjuster 22 on the right side of the vehicle body and a peripheral portion of the axle support portion 28. Installed.
The stopper 46 is a bolt, and its head 47 projects to the right side of the vehicle body. When the chain adjuster 22 rotates by a predetermined angle, the stopper 46 comes into contact with the brake caliper bracket 38 to restrict the further rotation of the chain adjuster 22. It has become.

As shown in FIG. 5, recesses 48 are provided at predetermined intervals around the left end of the chain adjuster 22 on the vehicle body, and a tool inserted through a gap between the cantilevered rear swing arm 6 and the damper 30 is provided. The chain adjuster 22 is rotatable by engaging with the recess 48.

Next, the operation of this embodiment will be described. When the tension of the chain 11 is loosened, the chain adjuster 22
4 is rotated in the direction indicated by the arrow A in FIG. 4 (clockwise direction), the axle support portion 28 is eccentrically rotated and its center C1 moves rearward of the vehicle body. , And further, the axle length, which is the distance between the front wheel axles 13, becomes longer. As a result, the tension of the chain 11 is adjusted to an appropriate value.

At this time, the stopper 46 is a bolt, which can be easily attached by forming the screw hole 45 in the right side surface 44 of the chain adjuster 22 in advance.
It can be easily attached to the chain adjuster 22 of various sizes and shapes, and even a model in which the stopper 46 is not initially provided can be easily added by post-processing. Further, by changing the position of the screw hole 45, it is possible to easily change the rotation restricting angle, and the amount of protrusion of the stopper 46 can be adjusted according to the contact partner side. It can also be used for the arm 6, which increases versatility.

Further, by providing the stopper 46 on the side of the chain adjuster 22, the brake caliper bracket 38 overlapping the chain adjuster 22 in a side view is brought into contact with the nearest rear swing arm side member, as is apparent from FIG. Since the stopper 46 can be used, the degree of freedom regarding the mounting position of the stopper 46 is increased, and the amount of protrusion can be relatively small, so that the stopper 46 can be reduced in size and weight.

Further, by providing the stopper 46 on the side of the chain adjuster 22, even when the size, shape, etc. of the chain adjuster 22 and the rear swing arm 6 change, the stopper 46 itself can be replaced or its mounting position can be changed. Therefore, it is not necessary to change the design of the rear swing arm 6 itself. Further, by using the bolt as the stopper 46, the stopper 46 can be detachably attached.

The contact of the stopper 46 with the brake caliper bracket 38 is not limited to the brake caliper bracket 38, but may be of any type as long as the stopper 46 can be contacted by the rotation of the stopper 46. For example, if the brake torque rod 43 is configured to cross the chain adjuster 22 in a side view, the brake torque rod 43 can be the contact partner. The stopper 46 does not necessarily need to be a bolt. For example, a pin-shaped member can be attached by clipping or the like.

[Brief description of the drawings]

FIG. 1 is a left side view of a main part of a vehicle body of a motorcycle to which the embodiment is applied.

FIG. 2 is an enlarged side view of a rear swing arm.

FIG. 3 is a plan view thereof.

FIG. 4 is a left side view of an adjuster portion.

FIG. 5 is a right side view of the same.

FIG. 6 is a sectional view taken along line 6-6 in FIG. 4;

[Explanation of symbols]

3: engine, 4: pivot frame, 5: pivot shaft, 6: rear swing arm, 7: rear wheel, 8: rear wheel axle, 9: driven sprocket, 22: chain adjuster, 28: axle support, 38: brake Caliper bracket, 43: Torque rod for brake, 46: Stopper

Claims (3)

[Claims] 1. A rear swing arm, a chain adjuster rotatably provided at a rear end thereof, and a rear wheel axle supported at an eccentric position of the chain adjuster, wherein the chain adjuster is rotated. In a motorcycle in which the rear wheel axle is eccentrically rotated to adjust the tension of the chain, a stopper is detachably provided on the chain adjuster, and the stopper contacts a rear swing arm side member located near the stopper. An eccentric chain adjuster structure for a motorcycle, wherein rotation of the chain adjuster beyond a predetermined range is restricted by contact with the chain adjuster. 2. The eccentric type chain adjuster structure for a motorcycle according to claim 1, wherein said stopper is a bolt. 3. The motorcycle according to claim 1, wherein the rear swing arm side member contacting the stopper is a brake caliper bracket or a brake torque rod overlapping the chain adjuster in a side view. Eccentric chain adjuster structure for cars.