JPH065995Y2 - Rear wheel support device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a rear wheel supporting device for a motorcycle, and more particularly to a rear wheel supporting device using a cantilever swing arm for mounting the rear axle. The thing which improved the sex.

[Prior Art] A rear wheel of a conventional motorcycle is generally supported on both sides by a bifurcated swing arm called a rear fork. That is, the rear end side of the swing arm is branched into a bifurcated shape, and the rear wheel is inserted into the bifurcated space of the swing arm and is supported by the rear axle inserted from the outside of the swing arm. However, if the rear wheel is supported by both-sided support of the rear axle, high strength can be obtained, but at the time of tire replacement, the rear wheel needs to be inserted into and removed from the forked part of the swing arm, and the rear axle needs to be pulled out and inserted. Takes time.

Therefore, recently, it has been considered to support the rear wheel of the motorcycle with a cantilever swing arm (see, for example, JP-A-61-161).
129386). According to this cantilever type rear wheel supporting device, the rear wheel is mounted from the one side surface side of the rear portion without branching the rear end side of the swing arm. Therefore, the detaching work can be performed only on one side, and there is an advantage that the assembling work is easy and the tires can be replaced quickly. Therefore, it is particularly advantageous for race cars that compete for seconds.

[Problems to be solved by the invention] However, when such a cantilever type rear wheel support type is used, the tip of a relatively long rear axle must be passed through a support hole of the rear axle formed at the end of the swing arm. I have to. However, this support hole is formed in the transverse direction at the end of the swing arm and is relatively long, and the inner peripheral surface of the bearing for bearing the rear axle faces the inside of the support hole. Therefore, in order to pass the rear axle through the support hole, it is necessary to center it so that the tip of the rear axle does not hit the inner peripheral surface of the bearing, etc., and this requires a relatively large amount of time and labor. . Therefore, an object of the present invention is to provide a rear wheel support device using a cantilever type swing arm with an improved mountability of a rear axle.

[Means for Solving Problems] The rear wheel support device of the present invention has the following configuration. That is, a bearing is provided at the end of the cantilever swing arm,
In a rear wheel support device for supporting a rear wheel on one side of the swing arm end portion via a rear axle supported by the bearing, the rear axle is stepped and gradually reduced in diameter toward one end in the longitudinal direction. The diameter-changing end of the swing arm is fastened such that the end on the small diameter side is fastened from one side of the swing arm and protrudes to the other side, and the end on the large diameter side. The rear wheel is attached to a flange integrally formed with the rear portion, and the bearings are provided in a pair at left and right sides of a swing arm through which the rear axle passes, and the inner diameter of the bearing on the side where the rear wheel is attached is larger than that of the other. It is characterized in that a portion having a large diameter and adjacent to each bearing supporting portion of the rear axle is formed as a step portion having a smaller diameter than each bearing supporting portion.

[Operation of the Invention] The rear wheel support device according to the present invention has a bearing provided at the end of a cantilever swing arm and a stepped rear axle that is supported by this bearing. Therefore, the small-diameter side end of the rear axle is made to penetrate into the bearing so as to project to the other side of the swing arm, and is fastened here. At this time, since the front end of the rear axle in the insertion direction is a small-diameter end, the rear axle is automatically centered during the insertion process and smoothly passes through the inside without colliding with the bearing or the like. Moreover, of the pair of bearings arranged at intervals with respect to the insertion direction of the rear axle, the inner diameter on the front side is large and the inner diameter on the back side is small, so that the tip side should be caught by the bearing when inserting the rear axle. Although the condition that it is difficult to insert quickly and quickly is adopted, the part adjacent to each bearing support part of the rear axle is formed in a step part with a smaller diameter than each bearing support part, so the inner diameter of each bearing can be more smoothly Can be penetrated.

[Embodiment] FIGS. 1 and 2 show an embodiment of the present invention. This will be described below with reference to the drawings.

A cantilever swing arm 4 is attached to a vehicle body frame 2 carrying a power unit 1 via a pivot 3. The swing arm 4 has its front end supported by a rear cushion unit 5. A rear wheel 14 is supported on the rear end portion. That is, a vertically split holder portion 6 is provided at the rear end of the swing arm 4, and the holder portion 6
An eccentric unit 7 having a cylindrical shape and supporting the rear axle in an eccentric manner is fitted therein. The holder part 6 is tightened up and down via a tightening part 8. If this is loosened, the eccentric unit 7 can be rotated. The eccentric unit 7 has a support hole 9 in its eccentric position, and a rear axle 10 is inserted in this support hole 9.

The rear axle 10 has a flange 11 integrally formed on one end side thereof, and the other end side thereof has steps 12a, 12d, 1
It is formed in a tapered shape in which the diameter is gradually reduced via 2b and 12c (hereinafter, the end portion on the small diameter side is referred to as a tip). In addition,
The rear axle 10 is formed in the shape of a hollow shaft, and one end side of the rear axle 10 is expanded in the direction perpendicular to the axis to form a flange 11. Mounting holes 13 are provided in the flange 11 at equal intervals in the circumferential direction. Outer surface 11a of flange 11
The wheel hub 15 of the rear wheel 14 abuts on the wheel hub 15 and is connected by bolts 16 and nuts 17 inserted into the mounting holes 13. Reference numeral 18 is a spoke of the rear wheel 14, and 19 is a tire. Further, the brake disc 20 is brought into contact with the inner side surface 11b of the flange 11, and these are connected by the bolt 21 and the nut 22 in the mounting hole 13.
A clearance 23 is formed in the rear wheel 14 to allow the flange 11 and the nut 22 to be mounted. Further, the brake portion is configured such that a caliper 26 is attached to a torque rod 25 screwed to a boss 24 formed on a swing arm, and a brake pad 27 is provided on the caliper 26 so that the brake disc 20 is engaged with the rear portion of the vehicle body. ing.

On the other hand, the rear axle 10 is an eccentric unit 7
Are supported at two axial positions via needle bearings 28 and ball bearings 29. The needle bearing 28 supports the large diameter portion on one end side of the rear axle 10 on one side surface portion of the eccentric unit 7, and the ball bearing 29 attaches the first step portion 12a formed at the substantially middle portion of the rear axle 10 to the eccentric unit 7.
It is supported by the other side surface. The needle bearing 28 is held by the eccentric unit 7 by a thrust washer 30, and a seal ring 31 is arranged outside the thrust washer 30. The ball bearing 29 is fixed to the eccentric unit 7 with a circlip 32, and the thrust washer 3 is attached from the outside.
Holds at 3. The thrust washer 33 is inserted and positioned from the other end side of the small diameter at the position of the second step portion 12b of the rear axle 10. The inner diameter of the needle bearing 28 is larger than the inner diameter of the ball bearing 29. Further, the portions of the rear axle 10 adjacent to the bearing supporting portions are stepped portions 12d and 12b having a diameter smaller than that of the bearing supporting portions.

Further, the drive unit 34 is connected to a portion of the rear axle 10 on the tip side from the second step 12b. This drive unit 34
Is the driven side of the chain drive mechanism. That is, this chain type drive mechanism is composed of the drive sprocket 35 of the power unit 1 and the driven sprocket 37 which is engaged via the chain 36 (see FIG. 1). The driven sprocket 37 is connected to the rear axle 10 via a damper 38. That is, the damper 38 is driven by the driven sprocket 37.
A cylindrical outer element 41 having one end opening attached to the outer element 41 with a bolt 39 and a nut 40.
Of the inner element 42 fitted in the opening of the radial damper blades 41a, 42a alternately projecting from the inner element 42
It is constituted by a damper bar 43 inserted between them. The outer element 41 has a second step 12b and a third step 12c of the rear axle 10 via a bearing 44.
And the outer element 41 is integrally rotatably connected to the other end side (the side opposite to the rear wheel 14) of the third step portion 12c of the rear axle 10 via the spline 45. There is. Further, a male screw is formed on the small diameter portion 46 at the tip of the rear axle 10 protruding from the inner element 42, and a nut 47 is fitted into the small diameter portion 46 from the outside of the inner element 42, and the tightening action by the nut 47 is The eccentric unit 7 through the boss portion 42b of the element 42, the bearing 44 of the outer element 41, the thrust washer 33, the circlip 32 and the bearing 29 held by the eccentric unit 7, and thus the rear axle 10 on the rear wheel 14 side. Is configured. Then, the driven sprocket 35 is driven by the driven sprocket 37 via the chain 36.
The rotational driving force transmitted to the damper 38 and the outer element 41 is transmitted to the damper blade 41a and the damper bar 4.
3 and the damper blades 42a of the inner element 42 are transmitted to the inner element 42 in a shock-absorbable state. The rotation of the inner element 42 is transmitted to the rear axle 10 via the spline 45, whereby the rear wheel 1
4 is rotationally driven.

Next, when assembling the vehicle body, first, the brake disc 20 is attached to the flange 11 of the rear axle 10. On the other hand, the eccentric unit 7 is fitted and fixed to the holder portion 6 of the swing arm 4. Then, the rear axle 10 is inserted into the support hole 9 of the eccentric unit 7 from the small diameter side which is the tip, and the bearing 29, the circlip 32 and the thrust washer 33 are fixed. Then, the damper 38 is attached to the tip of the rear axle 10, and the protruding portion is fixed with the nut 47. As a result, the rear axle 10
Is an eccentric unit 7 and a driven sprocket 3
It is supported by the end of the swing arm 4 in a state where 7 and the like are integrally connected. After that, if the wheel hub 15 is brought into contact with the flange 11 and connected by the bolt 16 and the nut 17,
The rear wheel 14 is attached to the flange 11.

When replacing the rear wheel 14, the rear wheel 14 can be easily removed by removing the bolt 16 and the nut 17 from the flange 11 integral with the rear axle 10. At this time, the rear axle 10 maintains the state in which the rear axle 10 is fixed to the holder portion 6 side in the left-right direction by the flange 11 and the nut 47.

When adjusting the stretched state of the chain 36, the tightening portion 8 of the holder portion 6 of the swing arm 4 is loosened and the eccentric unit 7 is rotated. Since the support hole 9 of the eccentric unit 7 is eccentric, the position of the rear axle 10 and the position of the driven sprocket 37 are changed by the rotation of the eccentric unit 7, and the tensioned state of the chain 36 can be adjusted.

According to the above-described embodiment, the rear axle 10 is step-molded, the tip side is tapered to have a small diameter, and the diameter is changed so as to be gradually reduced toward one end in the length direction, and the end portion on the large diameter side is formed. The rear wheel 14 is attached to the integrally formed flange 11, and of the pair of left and right bearings 28, 29 arranged at intervals to support the rear axle 10, the rear wheel 14 side which is the front side when the rear axle 10 is inserted. The inner diameter of the needle bearing 28 is larger than the inner diameter of the ball bearing 29 on the back side, and the rear axle 1
The portion adjacent to each bearing support portion of 0 was formed as step portions 12d and 12b having a diameter smaller than that of each bearing support portion.

Therefore, the rear axle 10 must be penetrated from one side (the right side in this embodiment) of the eccentric unit 7 provided on the swing arm 4 to the other side (the same left side), with the side without the flange 11 first, and Of the pair of left and right bearings 28, 29 arranged with a space, even if the ball bearing 29, which becomes the back at the time of insertion, has a smaller inner diameter, it is difficult to insert the rear axle 10 from the tip on the small diameter side. The stepped portion 12d that can be inserted and has a smaller diameter in the adjacent portion than each bearing support portion
And 12b, the tip of the rear axle 10 is centered with respect to the inner diameter of each bearing 28, 29,
Each bearing 28, 29, especially the ball bearing 2 at the back
You will be able to pass smoothly without getting caught in 9. Therefore, if the rear axle 10 is inserted into the eccentric unit 7 from the tip side thereof, the rear axle 10 can be smoothly inserted without any trouble. Step 1
Centering can be easily performed through 2a, 12b, and 12c, and members such as bearings and drive units can be easily connected to the stepped portions 12a, 12b, and 12c, and the mountability can be improved. Although the other end of the rear axle 10 for tightening the nut 47 is a small-diameter step portion, no special large load acts on this portion, so there is no problem in strength. Therefore, the flange 11 side, which requires rigidity, has a large diameter, and the tip side, which is not so required, has a small diameter. In this respect as well, the weight is reduced to an ideal shape. Moreover, since the flange 11 is also integrated with the rear axle 10, the rigidity of the flange 11 is increased through the integrally connected portion, so that it is not necessary to give the flange 11 an extra thickness. Moreover, in this embodiment, the flange 11
Since it has high rigidity, even the brake disc 20 can be attached thereto. Therefore, the rear wheel 14
Since it is not mounted on the side, the rear wheels 14 can be replaced without changing the brake device when tires are replaced. Therefore, it is suitable for race-specification vehicles that compete for exchanging seconds.

The present invention is not limited to the above embodiment, but various modifications and applications are possible. For example, the rear axle may have a single stage or multiple stages. Further, the end portion of the rear axle can be directly connected to the rear wheel by a nut without using a flange.

[Advantages of the Invention] According to the rear wheel support device of the present invention, the rear axle is stepped and the diameter is changed so as to be gradually reduced toward one end in the length direction, and is integrally formed at the end on the large diameter side. The rear wheels are mounted on the flanges, and the bearings that support the rear axle are arranged in pairs on the left and right of the swing arm through which the rear axle passes, with the inner diameter of the bearing on the side where the rear wheels are attached to the inner diameter of the bearing on the other side. The diameter of the rear axle is adjacent to each bearing support portion, and the portion adjacent to each bearing support portion is formed as a stepped portion having a diameter smaller than that of each bearing support portion.

Therefore, the rear axle must be penetrated from one side of the swing arm to the other side with the side without the flange first, and the inner diameter of the bearing at the back of the pair of bearings is smaller, so do not insert it. Even if it has a leech structure, the rear axle can be inserted from the tip of the small diameter side, and since the adjacent part is a step with a smaller diameter than the bearing support part, the tip of the rear axle is the inner diameter of each bearing. Since it is centered with respect to each other, it can pass smoothly without being caught in each bearing, and the mountability of the rear axle can be improved.
As a result, the rear wheels can be easily replaced in a very short time. Moreover, since the rear axle is tapered, the weight of the rear axle can be reduced as much as possible.

[Brief description of drawings]

FIG. 1 is a side view of an essential part showing an embodiment of the present invention, and FIG. 2 is a partially enlarged transverse sectional view of FIG. (Description of symbols) 4 ... Swing arm, 6 ... Holder part, 7 ... Eccentric unit, 10 ... Rear axle, 11 ...
Flange, 12a, 12b, 12c ... Step, 14 ...
Rear wheel, 15 ... Wheel hub, 20 ... Brake disc, 28 ... Needle bearing, 29 ... Ball bearing, 34 ... Drive part, 38 ... Damper, 47 ... Nut.

Claims (1)

[Scope of utility model registration request] 1. A cantilever type rear wheel supporting device for supporting a rear wheel at one end of a rear axle which is crossed by an end of a swing arm and is supported by a bearing, wherein the rear axle is stepped and has one end in a longitudinal direction. The diameter is changed so that the diameter gradually decreases toward the end of the swing arm, and the end on the smaller diameter side is fastened from one side of the swing arm to the other side through the inside of the bearing. The rear wheel is attached to a flange integrally formed at the end on the large diameter side, and the bearings are provided in a pair on the left and right of the swing arm through which the rear axle passes, with the rear wheel attached. The inner diameter of the bearing is larger than the other, and the part adjacent to each bearing support part of the rear axle is formed as a step part with a smaller diameter than each bearing support part. Wheel supporting apparatus after it characterized.