JPH0688481B2 - Axle bearing structure in vehicles such as motorcycles - Google Patents

Description

The present invention relates to a bearing portion structure of an axle in a vehicle such as a motorcycle.

[Conventional technology]

Generally, in a vehicle such as a motorcycle, for example, JP-A-59-
As disclosed in Japanese Patent No. 7791, ball bearings are arranged at predetermined intervals in an axle case integrally formed at one end of a swing arm, and a solid axle is rotatably supported through the ball bearings. is doing.

[Problems to be Solved by the Invention] However, in recent years, the number of vehicles using hollow axles has been increasing due to the tendency to reduce the weight of vehicle bodies. In this case, one having a larger axle diameter than a solid axle in terms of strength is used. If you use, the ball bearing fitted on the axle also has a large outer diameter,
The weight of the ball bearing is also heavy.

Therefore, it is an object of the present invention to provide a bearing portion structure of an axle in a vehicle such as a motorcycle in which the weight of the bearing portion is reduced.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention relates to an axle of a vehicle such as a motorcycle that rotatably supports a hollow axle via a bearing arranged in an axle case attached to one end of a swing arm. In the vehicle receiving portion structure, a small-diameter shaft portion and a large-diameter shaft portion are continuously provided on the axle, and a ball bearing is fitted to the small-diameter shaft portion, and the ball bearing is attached to the small-diameter shaft portion and the large-diameter shaft portion. And a fixing member such as a nut provided outside the ball bearing, and a needle bearing is fitted to the large-diameter shaft portion apart from the ball bearing and fitted to the axle. A swing arm is externally fitted to the portion of the axle case that corresponds between the ball bearing and the needle bearing, and the small-diameter shaft portion is projected from the axle case. The inner peripheral side base of the sprocket for use is axially attached, and the outer peripheral side of the sprocket is formed so as to be offset from the inner peripheral side base so as to be located substantially flush with the ball bearing outside the axle case. It is characterized by that.

〔Example〕

An embodiment in which the present invention is applied to a motorcycle in which a rear wheel is cantilevered by a single swing arm will be described with reference to the drawings.

An axle case 2 is attached to one end of the swing arm 1, and a hollow axle 3 is rotatably inserted in the axle case 2 via ball bearings 4 and 4 and a needle bearing 5.

The axle 3 has a small-diameter shaft portion 3a and a large-diameter shaft portion 3b connected in series,
Ball bearings 4, 4 are fitted to the small-diameter shaft portion 3a, and needle bearings 5 are fitted to the large-diameter shaft portion 3b at positions separated from the ball bearings 4, 4.

The ball bearings 4, 4 are axially tightened into the inside of the axle case 2 by a ring nut 6, which is a fixing member screwed to one end of the axle case 2, and the inner side has a small diameter shaft portion 3a and a large diameter shaft. Step portion 3c formed between the portion 3b and
And a large-diameter stepped portion 2a formed in the axle case 2 so as to be fixed between the axle case 2 and the axle 3.

The needle bearing 5 is provided with ring-shaped seals 7a and 7b at both ends, the inner seal 7a is supported by the step portion 2b of the axle case 2, and the outer seal 7b is fitted to the axle case 2. The circlip 8 is used to prevent it from coming off, and like the ball bearings 4, 4, is fixed between the axle case 2 and the axle 3.

And these ball bearings 4, which are fitted to the axle 3,
One end of the swing arm 1 is externally fitted to a portion of the axle case corresponding to between the 4 and the needle bearing 5.

Small diameter shaft part 3a in which the ball bearings 4, 4 are fitted
Has one end protruding from one end of the axle case 2, and a driven sprocket 9 is axially attached to this protruding portion. The driven sprocket 9 has an inner peripheral side base portion on the axle mounting side that is serration-fitted to the protruding portion of the small diameter shaft portion 3a, and is fixed to the outer side thereof by a nut 12 screwed through washers 10 and 11. . The outer periphery of the driven sprocket 9
It is formed so as to be offset to one side of the inner peripheral side base portion, and is disposed outside the axle case 2 and on substantially the same plane as the ball bearings 4 and 4 by the above-mentioned mounting.

On the other hand, the large diameter shaft portion 3b protruding from the other end of the axle case 2
Has a flange 3d for mounting the wheel and disc rotor
Four wheel mounting pins 13 projecting to the side opposite to the swing arm are attached to the flange 3d by nuts 14 at equal intervals.

A spacer 15 is fitted on the outer periphery of the large-diameter shaft portion 3b,
Further, a rear wheel 16 is attached to the outer circumference thereof. Rear wheel 16
The hub portion 16a has pin insertion holes 16b formed at four equal intervals corresponding to the above-mentioned pins 13, and the rear wheel 16 inserts the wheel mounting pins 13 into these pin insertion holes 16b, respectively. Then, by the nut 17 screwed to the outer end side of the large diameter shaft portion 3b,
It is attached so as to rotate integrally with the axle 3.

A split pin 18 for preventing the nut 17 from coming off is attached to the end of the large-diameter shaft portion 3b. This pin 18 has a large diameter shaft 3b
The pin holes 3e, 3e formed in the pin 3 and the guide hole 19a of the pin guide 19 inserted in the end of the large-diameter shaft portion 3b, and the nut 1
By preventing 7 from slipping out, the rear wheel 16 rotating at high speed integrally with the axle 3 is securely fixed.

In the present embodiment, as described above, the large diameter ball bearings 4, 4 bearing a high load are axially attached to the small diameter shaft portion 3a of the axle 3 to secure the necessary bearing capacity, and the needle bearing 5
Is used in combination with the large-diameter shaft portion 3b, the weight of the bearing portion can be improved while increasing the diameter of the axle shaft 3 and ensuring the strength of the axle shaft 3.

Further, by fixing these ball bearings 4 and 4 with the stepped portion 3c of the small diameter shaft portion 3a and the large diameter shaft portion 3b and the fixing member such as the ring nut 6, the thrust load applied to the axle 3 is ball bearing. Since it can be received by 4 and 4, the needle bearing 5 need not receive thrust load but only radial load, so it is not necessary to secure the bearing volume excessively, and the bearing part can be made more compact. it can.

In addition, ball bearings 4, 4 and needle bearings 5
Since one end of the swing arm 1 is externally fitted to the portion of the axle case 2 corresponding to these ball bearings 4 and 4 and the needle bearing 5, the swing arm 1 receives and distributes the load. Bearings
The burden of 4,5 can be reduced and the bearings 4,5 can be made smaller.

Moreover, the small-diameter shaft portion 3a of the axle 3 is projected from the axle case 2, and the inner peripheral side base portion of the driven sprocket 9 for power transmission is pivotally attached to the protruding portion, and the outer peripheral side of the driven sprocket 9 is attached to the axle case. Since the ball bearings 4 and 4 are disposed on the outer side of the surface 2 and substantially on the same plane, the moment force around the shaft is reduced and the axle 3 can be made thinner.

〔The invention's effect〕

As described above, according to the present invention, a small-diameter shaft portion and a large-diameter shaft portion are connected to a hollow axle provided in an axle case mounted on one end of a swing arm, and a ball bearing is attached to the small-diameter shaft portion. The ball bearing is fitted and fixed by the stepped portion of the small diameter shaft portion and the large diameter shaft portion and a fixing member such as a nut provided outside the ball bearing, and the needle bearing is attached to the large diameter shaft portion. Fitted apart from the ball bearings, the swing arm is externally fitted to the portion of the axle case corresponding between these ball bearings and needle bearings, and the small diameter shaft portion is projected from the axle case, The inner peripheral side base of the sprocket for power transmission is axially mounted, and the outer peripheral side of the sprocket is positioned outside the axle case on substantially the same plane as the ball bearing. Since it is formed by eccentricity, the thrust load applied to the axle can be received by the ball bearing that is fitted to the small diameter shaft part and regulates axial movement, so the large diameter shaft used separately from this Since only the radial force needs to be received by the needle bearing of the portion, it is not necessary to secure the bearing capacity excessively while securing the strength by increasing the diameter of the axle, and the bearing portion can be made smaller and lighter.

Further, the ball bearing and the needle bearing are separated from each other, and one end of the swing arm is externally fitted to the portion of the axle case corresponding to the space between the both bearings. The load on the bearings is reduced and both bearings can be made smaller.

Moreover, the small diameter shaft portion is projected from the axle case, the inner peripheral side base portion of the driven sprocket for power transmission is axially attached to the protruding portion, and the outer peripheral side of the driven sprocket is attached to the ball bearing outside the axle case. Since they are arranged on substantially the same plane, the moment force around the shaft is reduced, and the thickness of the axle can be reduced.

[Brief description of drawings]

FIG. 1 is a sectional view showing a rear wheel of a motorcycle to which an embodiment of the present invention is applied, and FIG. 2 is an enlarged view of a needle bearing. 1 ... Swing arm, 2 ... Axle case, 3 ...
Axle, 3a ... small diameter shaft, 3b ... large diameter shaft, 4 ... ball bearing, 5 ... needle bearing, 6 ... ring nut, 7a, 7b ... seal, 9 ... driving sprocket, 13 ... … Wheel mounting pin, 16 …… rear wheel

Claims (1)

[Claims] 1. A wheel receiving portion structure for an axle in a vehicle, such as a motorcycle, which rotatably supports a hollow axle via a bearing arranged in an axle case mounted at one end of a swing arm. A small-diameter shaft portion and a large-diameter shaft portion are continuously provided on an axle, and a ball bearing is fitted to the small-diameter shaft portion, and the ball bearing is provided with a step portion between the small-diameter shaft portion and the large-diameter shaft portion, and a ball. The ball bearing and the needle bearing which are fixed to a fixing member such as a nut provided on the outer side of the bearing and are fitted on the large-diameter shaft portion apart from the ball bearing, and are fitted on the axle. A swing arm is externally fitted to the portion of the axle case corresponding to the position of the sprocket and the small-diameter shaft portion is projected from the axle case. A motorcycle in which a side base portion is pivotally mounted, and an outer peripheral side of the sprocket is formed so as to be offset from the inner peripheral side base portion so as to be located substantially on the same plane as the ball bearing outside the axle case. Axle bearing structure in vehicles such as.