JP2002120786A - Chain guide device for motorcycle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance elastic deformation property and absorb pressing force by tension of a chain during deceleration with high responsiveness, and thereby reduce force springing up a rear wheel, prevent the rear wheel from springing up, and thereby improve ride comfort of a motorcycle. SOLUTION: In this chain guide device 30 for the motorcycle, a holding piece 41 is extended downward from a swing arm 21 of the motorcycle 10 and guide rollers 36 and 37 are rotatably installed on the holding piece 41 so that the guide rollers 36 and 37 guide the chain 24. The rigidity is lowered and the elastic deformation property is enhanced by forming plural hollow parts 56 on the guide rollers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a chain guide device for a motorcycle.

[0002]

2. Description of the Related Art A chain guide device for guiding a chain for driving a rear wheel of a motorcycle is disclosed in
No. 178,491 entitled "Motorcycle Chain Guide". According to FIG. 1 of the publication, the chain guide of this motorcycle has a holding plate 6 attached to the swing arm 1, guide rollers 9, 9 attached to the holding plate 6, and a chain 4 attached to these guide rollers 9, 9. The guide rollers 9, 9 can be kept at predetermined positions to prevent the chain 4 from coming off.

[0003]

The chain guide disclosed in the above publication prevents the chain 4 from being separated from the rear wheel sprocket 2 by the holding plate 6 and the guide rollers 9 and 9. In this case, when the vehicle decelerates, a pulling force acts on the chain 4 on the chain guide side, and the chain 4 is strongly stretched in a straight line.

[0004] It is an object of the present invention to provide a motorcycle chain guide device that can improve ride comfort.

[0005]

According to a first aspect of the present invention, a holding piece is extended downward from a swing arm of a motorcycle, and a guide member for guiding a chain is attached to the holding piece. In addition, by forming a hollow portion, rigidity is reduced and elastic deformation is enhanced. Tension occurs in the chain guided by the chain guide device at the time of deceleration, and the chain presses the guide roller with a force that attempts to return to a straight line. Since the rigidity was reduced and the elastic deformability was increased by forming a hollow part in the guide member,
The guide member elastically deforms in response to the pressing force of the chain during deceleration, and absorbs the pressing force. As a result, there is no fear that the rear wheel will jump up.

According to a second aspect of the present invention, the guide member is a guide roller having a plurality of hollow portions. By forming the hollow portion, the rigidity is reduced, the elastic deformability is enhanced, and the guide roller is used, so that it becomes easier to cope with the pressing force of the chain during deceleration, and the pressing force is absorbed with higher response. As a result, the jump of the rear wheel is more reliably suppressed.

According to a third aspect of the present invention, a plurality of guide rollers are arranged along the chain. Arrange multiple guide rollers along the chain, adjust the slack mainly with the guide roller on the center side of the chain, and press the chain mainly on the rear sprocket with the guide roller on the rear sprocket side of the rear wheel, Prevent chain flapping.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is a side view of a motorcycle according to the present invention. In a motorcycle 10, a handle post 14 and a front fork 15 are attached to a head pipe 13 at a front end of a body frame 12 so as to be steerable.
5, a front wheel 16 is attached, an engine 17 is provided at a lower center portion of the body frame 12, a fuel tank 18 and a seat 19 are provided at an upper portion, and a swing arm 2 is provided at a lower rear portion of the body frame 12.
1 is vertically movably extended, a rear wheel 22 is attached to the rear of the swing arm 21, and a rear sprocket 23 attached to the rear wheel 22 is driven by a driving sprocket 25 on the engine side via a chain 24. Things. Reference numeral 30 denotes a chain guide device provided on the swing arm 21.

FIG. 2 is a detailed view of a portion 2 of FIG. 1, and is a side view of the chain guide device. Chain guide device 30
Are brackets 32, 33 attached to the lower part 31 of the swing arm 21, holding means 34 attached to these brackets 32, 33, an upper guide 35 attached to the bracket 32, and a guide roller 3 attached to the holding means 34.
6, 37. 38, 38 and 38a are bolts for attaching the holding means 34, and 39 and 39 are bolts for attaching the guide rollers 36 and 37.

FIG. 3 is a view taken in the direction of arrows 3-3 in FIG. 2, and shows the holding means 34 attached to the lower part 31 of the swing arm 21. The holding means 34 includes a left holding piece 41 extending downward from the swing arm 21 and a right holding piece 42.

The left holding piece 41 has a lug 44 formed on a plate-shaped main body 43, which is attached to the bracket 33 with bolts 38a, and the main body 43 is attached to the bracket 32 with bolts 38, 38 (see FIG. 2). ). The right holding piece 42 is obtained by attaching a plate-shaped main body 45 to the bracket 32 with bolts 38, 38.

FIG. 4 is a sectional view taken along the line 4-4 in FIG. 2, in which an upper guide 35 is provided at the upper part 44 of the left and right holding pieces 41, 42, and a guide roller 36, 37 (see FIG. 2). The guide roller 37 is the same as the guide roller 36, and a detailed description is omitted. The upper guide 35 has a mounting hole 47 formed in the upper part and a concave guide part 48 formed in the lower part. The guide part 48 guides the chain 24 which has risen upward.

The guide roller 36 has a hole 52 at the center of the roller 51 and bearings 53 and 52 at both ends of the hole 52.
A concave portion 55 for accommodating the recess 54 is provided, and a hollow portion 56... , 5
5 is a bearing-equipped roller in which bearings 53 and 54 are attached to the bearing 5 and a steel collar 57 is attached between the bearings 53 and 54. 58 and 58 are washers. The material of the guide roller 36 is preferably hard resin or hard rubber (for example, urethane rubber).

The lower portions 46 of the left and right holding pieces 41, 42
Are provided with guide rollers 36, 37, but the holding pieces 41, 4
The configuration of the guide member attached to 2 may be a fixed one instead of a rotating roller with a bearing. Further, the shape of the guide member is not limited to a cylinder, and may be a prism having a hollow portion.
(See FIG. 1). Furthermore, upper guide 3
The hollow part is formed in an integral shape as shown in FIG.
9 may be fixed.

FIG. 5 is a sectional view taken in the direction of the arrow 5 in FIG.
0 hollow portions 56 are shown. That is, the hollow portion 56
In the figure, a substantially triangular through hole is arranged on a circle centered on the hole 52. By forming a plurality of hollow portions 56 in the guide roller 36, the guide roller 3
6 can be reduced and the elastic deformability can be increased.

The operation of the above-described motorcycle chain guide device will now be described. 6 (a) and 6 (b) are operation diagrams of the chain guide device for a motorcycle according to the present invention.

In (a), when the motorcycle 10 normally travels, a rear sprocket 23 attached to a rear wheel 22 is driven by a driving sprocket 25 on the engine side via a chain 24 as shown by an arrow. At this time, the tension due to the power is applied to the chain 24a above the center of the rear sprocket 23 and the center of the drive sprocket 25 as shown by the arrow. At the same time, a force is generated as shown by the arrow in the chain 24a, the chain 24a is not loosened, and the chain 24a is stretched straight. Conversely, while the loose amount Y1 is generated in the loose lower chain 24b, the lower chain 24b
It is guided by the chain guide device 30.

In the chain guide device 30, the chain 2
Since two guide rollers 36 and 37 are arranged along 4, the guide rollers 36 mainly prevent excessive loosening,
The guide roller 37 can mainly press the rear sprocket 23. As a result, the lower chain 24
The fluttering of the chain 24 in which b is wavy can be suppressed.

In (b), when the motorcycle 10 is decelerated, especially when an engine brake is used, tension is generated in the lower chain 24b as shown by an arrow. At that time, the chain 24b is not loosened, and a downward pressing force F is generated while being stretched straight. At this time,
The chain 24b pressed by the chain guide device 30 attempts to return to a straight line, and the rear wheel 22 starts to jump up as shown by an arrow.
Absorb the downward pressing force F by the guide member. This will be specifically described with reference to FIG.

FIG. 7 is a detailed view of a portion 7 of FIG. 6, and shows the chain guide device 30 during normal running. Since the two guide rollers 36 and 37 are arranged as shown in the figure, the guide rollers 36 and 37 rotate as shown by arrows, and guide the chain 24b with a predetermined slack to the rear sprocket while pressing it more securely. Can be.

The guide rollers 36 and 37 are formed with hollow portions 56.
With the arrangement of 6, 37, desired elastic deformation can be set. As a result, the guide rollers 36 and 37 can give a predetermined looseness and tension to the chain 24b without excessively deforming elastically, and can guide the chain 24 smoothly.

FIG. 8 is a detailed view of a portion 8 of FIG. 6, and shows the chain guide device 30 when decelerating. When a downward pressing force F is generated on the chain 24b due to the deceleration, the guide rollers 36 and 37 are elastically deformed and absorb the pressing force F. That is, by forming a plurality of hollow portions 56 in the guide rollers 36, 37, the guide rollers 36, 37 are formed.
Of the chain 24b generated at the time of deceleration can be absorbed with high response, and the amount of elastic deformation can be set large. As a result, the force for jumping up the rear wheel is attenuated, and it is possible to prevent the rear wheel from jumping up.
Therefore, the ride comfort can be improved.

Further, since the guide rollers 36 and 37 rotate, the pressing force F of the chain 24b can be more reliably absorbed, and the riding comfort can be improved.
As shown in FIG. 7, since the guide rollers 36 and 37 rotate, the wear resistance of the guide rollers 36 and 37 can be improved. As shown in FIG. 3, the guide rollers 36,
Since the 37 is attached with the left and right holding pieces 41, 42 and the bolts 39, 39, the attachment and detachment of the guide rollers 36, 37 are easy, and the maintainability can be improved.

The shapes of the holding pieces 41 and 42 shown in FIG. 3 according to the embodiment of the present invention are arbitrary. The number of guide rollers may be one, and may be more than two. It is also possible to arrange the guide rollers having different outer diameters in combination. The shape and the number of the hollow portions 56 are arbitrary, and the elastic deformability can be adjusted by changing the shape and the number. Further, elastic deformation may be adjusted by changing the material.

[0025]

According to the present invention, the following effects are exhibited by the above configuration. According to the first aspect, the holding piece is extended downward from the swing arm of the motorcycle, a guide member for guiding the chain is attached to the holding piece, and a rigid portion is reduced by forming a hollow portion in the guide member, thereby reducing elastic deformation. Increased. As a result, the pressing force due to the tension of the chain during deceleration can be absorbed. That is, the pressing force for the chain to return to a linear shape propagates and acts to jump up the rear wheel. However, since this pressing force is attenuated, it is possible to prevent the rear wheel from jumping up. Therefore, the ride comfort can be improved.

In the second aspect, since the guide member is a guide roller having a plurality of hollow portions, the pressing force due to the tension of the chain during deceleration can be absorbed with higher response. As a result, it is possible to prevent the rear wheel from jumping up,
The ride comfort can be further improved.

According to the third aspect of the present invention, since the guide rollers are arranged along the chain, the slack is appropriately adjusted mainly by the guide roller on the center side of the chain, and the guide roller is mainly adjusted by the guide roller on the rear sprocket side of the rear wheel. Press the chain against the rear sprocket. As a result, the rattling of the chain can be suppressed more reliably.

[Brief description of the drawings]

FIG. 1 is a side view of a motorcycle according to the present invention.

FIG. 2 is a detailed view of two parts of FIG. 1;

FIG. 3 is a view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 in FIG. 2;

FIG. 5 is a sectional view taken along arrow 5 in FIG.

FIG. 6 is an operation view of a chain guide device for a motorcycle according to the present invention.

FIG. 7 is a detailed view of part 7 of FIG. 6;

FIG. 8 is a detailed view of part 8 of FIG. 6;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Motorcycle, 21 ... Swing arm, 24 ... Chain, 30 ... Chain guide device, 36, 37 ... Guide roller, 41 ... Left holding piece, 42 ... Right holding piece, 56 ...
Hollow part.

Claims (3)

[Claims] 1. A holding piece is extended downward from a swing arm of a motorcycle, a guide member for guiding a chain is attached to the holding piece, and a rigid portion is reduced by forming a hollow portion in the guide member, thereby reducing elastic deformation. A chain guide device for a motorcycle, characterized in that the height is increased. 2. The chain guide device for a motorcycle according to claim 1, wherein the guide member is a guide roller having a plurality of hollow portions. 3. The chain guide device for a motorcycle according to claim 2, wherein a plurality of the guide rollers are arranged along a chain.