JP2683916B2 - Chain receiving roller mounting structure for motorcycles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a chain receiving roller mounting structure for a motorcycle.

[Conventional technology]

In a motorcycle, particularly a motorcycle traveling on an uneven terrain, a swing stroke of a rear arm is set to be large. By the way, when the rear arm swings greatly, the drive shaft of the engine and the rear wheel axle become relatively close to each other due to the structure.
The drive chain may sag. Therefore, conventionally, a roller rotatably supported by a plate-shaped bracket welded to a frame is arranged above and below the drive chain, and the drive chain is brought into contact with the roller when the rear arm swings largely. In this way, it is known that the slack of the drive chain is removed and the rear chain receives an impact acting on the rear arm.

[Problems to be solved by the invention]

However, in such a structure, since the bracket formed separately is welded to the frame, not only the number of parts increases, but also the bracket is interposed between the frame and the roller to accurately align the roller. It was difficult to do. Further, since the roller is supported in an overhang state, the plate-shaped bracket cannot necessarily firmly support the roller. The present invention has been made in view of the above circumstances, and provides a chain receiving roller mounting structure for a motorcycle, in which the number of parts is reduced, the rollers can be easily aligned, and the rollers can be firmly supported. .

[Means for solving the problem]

The chain receiving roller mounting structure according to the present invention forms a rear arm support bracket that forms a part of a frame by making a pair of left and right halves face each other, and the left and right halves are formed on the upper and lower parts of the rear arm support bracket. A support shaft extending horizontally is provided between the rollers, and a roller is rotatably supported on the support shaft.

[Action]

In the present invention, the support shaft supporting the roller is firmly supported over a wide span by utilizing the rear arm support bracket having strength.

〔Example〕

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings.
1 is a sectional view taken along line I-I of FIG. 3 showing a frame of a motorcycle in which a chain receiving roller mounting structure according to the present invention is implemented, and FIG. 1 is a sectional view taken along line II-II of FIG. Third
The drawing is a side view showing the frame of the motorcycle, and FIG. 4 is a side view showing the entire motorcycle. In FIG. 3, the reference numeral 1 indicates the frame. The frame 1 includes a head pipe 2, a tank rail 4 that forms an upper portion of the frame 1 and supports a fuel tank 3, and a down tube 6 that is disposed below the tank rail 4 and supports a front side of an engine 5.
It is composed of The tank rail 4 is made of a single pipe material having a circular cross section, the front end of which is connected to the upper portion of the head pipe 2 by welding and extends rearward and rearward toward the rear of the vehicle body.

On the other hand, the down tube 6 is one upper tube 6a welded to the lower part of the head pipe 2 and this upper tube 6a.
A pair of left and right lower tubes 6b branched from the bottom of the
Consists of The lower tube 6b extends downward along the front side of the engine and then extends substantially horizontally rearward along the lower side of the engine.

A connecting member 7 is connected to the rear end of the tank rail 4. The connecting member 7 is formed by facing a pair of upper and lower halves each having a groove shape in cross section, and has a substantially Y shape for connecting the pair of left and right seat pillar tubes 8, 8. Further, a support bracket 9 constituting a pivoting portion for pivotally attaching an upper end portion of a shock absorber, which will be described later, is fixed to the back surface thereof. This support bracket 9
Is formed by bending an iron plate into a U-shape that is opened downward.

Reference numeral 11 is a rear arm support bracket that supports the rear arm 12. The rear arm support bracket 11 is formed by facing a pair of left and right halves 11a, 11b having a groove shape in cross section, and connects the seat pillar tubes 8, 8 with the rear end of the lower tube 6b. And forms part of the frame 1. Further, as shown in FIG. 5, cylindrical bosses 13 and 13 are fixed to the substantially central portion, and the rear arm 12 is pivotally supported by a pivot 14 which is laterally installed between the bosses 13 and 13. A drive sprocket 15 for the engine 5 is arranged in front of the pivot 14, and a drive chain 17 for driving a rear wheel 16 is attached thereto.

21 is a rear arm support bracket arranged on the left side of the vehicle body
The upper projection of the rear part of the upper portion of 11 is projected rearward, and the reference numeral 22 is the lower projection of the rear part of the rear arm support bracket 11 projected rearward. Numerals 23, 23 are rollers which are rotatably supported by the vertical projections 21, 22, and which receive the drive chain 17 when the rear arm 12 swings largely. Explaining the support of the roller 23 in detail, 24 is a half body 11 forming each protrusion.
A support boss horizontally provided between a and 11b, 25 is a support bolt as a support shaft inserted into the support boss 24, and 26 is a nut screwed to the support bolt 25. The roller 23 is rotatably supported on a bearing bolt 27 by means of a pivot bolt, and its movement in the vehicle width direction is restricted by a nut 26 and a support boss 24.

Here, the roller support position is such that when the rear arm 12 is within the normal stroke range, the roller 23 is the drive chain.
When the rear arm 12 swings with a larger stroke without coming into contact with the roller 17, the roller 23 moves to the drive chain 17
The position is set so that it touches. Vertical protrusion 2
A concave portion 28 is provided in the outer half body 11a forming the portions 1 and 22 to prevent the head portion of the support bolt 25 from protruding laterally of the vehicle body.

31 is a shock absorber that damps the swing of the rear arm 12,
The shock absorber 31 is disposed in the center of the vehicle body immediately behind the engine 5, the lower end is connected to the rear arm 12 via a link mechanism 32, and the upper end is pivotally attached to the support bracket 9 with bolts and nuts. There is. The link mechanism 32 includes a first link 33 that is L-shaped in a side view and is pivotally attached to a cross member that connects the left and right rear arm support brackets 11, and a second link 34 that is linear and is a side view that is pivotally attached to the rear arm 12. Become. Shock absorber 31
The lower end of the second link 34 is pivotally attached to the pivot end of the first link 33, and the pivot end of the second link 34 is pivotally attached to the bent portion of the first link 33.

Reference numeral 35 is a seat rail that supports the seat 36, and 37 is a backstay that supports the rear portion of the seat rail 35. The seat rail 35 is welded to both side surfaces of the support bracket 9 and extends rearward and upward.

In the chain receiving roller mounting structure for a motorcycle configured as described above, a support bolt that supports the roller 23 is used.
The left and right halves 11a and 11b of the rear arm support bracket 11 having strength can firmly support the 25 over a wide span. Therefore, even the roller 23 supported in the overhang state can be firmly supported. As a result, when the motorcycle jumps, the rear arm 12 swinging downward due to the elastic force of the shock absorber 31 can be received by the lower roller 23 via the drive chain 17, and the motorcycle can jump from the jumped state. When landing, the upper roller 23 can receive a large impact acting on the rear arm 12 by its own weight.

Further, since the member supporting the rear arm 12 and the member supporting the roller 23 can be commonly used, the roller
The number of parts can be reduced compared to a structure in which a special bracket is provided to support 23. Moreover, since the boss 13 supporting the rear arm 12 and the support boss 24 for supporting the roller may be provided on the rear arm support bracket 11 which is the same member, the supporting position of the roller 23 can be easily set with the position of the boss 13 as a reference. Can be positioned.

In the embodiment, since the concave portion 28 is provided in the outer half body 11a, it is possible to prevent the head portion of the support bolt 25 from protruding. Therefore, the clothes of the operator are not caught.

〔The invention's effect〕

As described above, according to the present invention, a rear arm support bracket that forms a part of a frame is formed by facing a pair of left and right halves, and the left and right halves are formed on the upper and lower portions of the rear arm support bracket. Since a supporting shaft is installed between them and the roller is rotatably supported on this supporting shaft, the supporting shaft supporting the roller is firmly supported over a wide span by using the strong rear arm support bracket. can do.

Therefore, the roller can be firmly supported and a large impact acting on the rear arm can be received by the roller via the drive chain, and the member supporting the rear arm and the member supporting the roller can be commonly used. The points can be reduced. Moreover, since the support shaft position may be determined with reference to the rear arm support portion of the rear arm support bracket, the support position of the roller can be easily positioned.

[Brief description of the drawings]

1 is a sectional view taken along line I-I of FIG. 3 showing a frame of a motorcycle in which a chain receiving roller mounting structure according to the present invention is implemented, and FIG. 2 is a sectional view taken along line II-II of FIG. Third
FIG. 4 is a side view showing the frame of the motorcycle, FIG. 4 is a side view showing the entire motorcycle, and FIG. 5 is a sectional view taken along the line VV of FIG. 11 …… Rear arm support bracket, 12 …… Rear arm,
13 …… Boss, 17 …… Drive chain, 21 …… Upward protrusion, 22
...... Lower protruding part, 23 …… Roller, 24 …… Support boss.

Claims (1)

(57) [Claims] 1. A rear arm support bracket which forms a part of a frame is formed by facing a pair of left and right halves each having a groove shape in cross section, and the left and right halves are formed on an upper part and a lower part of the rear arm support bracket. A chain receiving roller mounting structure for a motorcycle, in which a supporting shaft that is laterally mounted is provided, and a roller that receives a drive chain is rotatably supported on the supporting shaft.