JPS58134269A - Sealing device of wheel driving portion of shaft drive- type motorcycle - Google Patents

Abstract

PURPOSE:To reduce the whole axial length by extending a cylindrical holder with a seal member from a gear shaft to the inside diameter of a driven flange cylinder portion in such a manner as to wrap them. CONSTITUTION:The base of a driven flange 28 is provided with a sleeve portion 30. The inside diameter portion 31 of a journal portion 23 is of a large diameter, and fitted to the sleeve portion 30 to be engaged with each other at spline portions 30a, 31a thereof. An O-ring 32 is disposed in a surrounding ring-shaped space S formed on one axial end of the spline portion to seal the driven flange and a shaft at each one end side thereof. A forward end portion 34a of a cylindrical holder 34 is joined to the small-diameter inside diameter portion 33 mounted on the shaft. A concave groove 35 is formed on the holder 34, and an O-ring 36 is fitted in the groove, the outside diameter portion of the O-ring 36 being brought into contact with the inside portion 37 of the sleeve portion 30 of the driven flange 28.

Description

[Detailed Description of the Invention] The present invention provides shaft drive type motorized two-wheeled vehicles, etc.
The present invention relates to a sealing device that seals a spline engagement portion between a driven flange that drives a wheel and a final driven member that is driven by a bevel gear or the like.

The heavy wheel drive section of a shaft-drive type motorcycle is constructed as shown in Fig. 4, and has an axially extending section on a gear shaft 51 which is the final driven member and includes a bevel gear driven by a propeller shaft through a bevel gear. 51a is provided, and an inner diameter spline portion 52 is provided on the inner diameter portion 51b of this,
On the other hand, an axially long cylindrical portion 53a is provided at the base of a driven flange 53 that transmits power to the hub via an elastic body, and an outer diameter spline portion 54 is provided at an axially intermediate outer diameter portion 53b of the cylindrical portion 53a, and these spline portions 52 ．． -54 is engaged, and the power to the gear shaft 51 is transmitted to the driven flange 753. By the way, since there is a gear meshing part around this area and it is lubricated, an oil seal is required, so conventionally, as shown in the figure, a driven flage 5 between the spline parts 52 and 54 is used.
An O-ring 55 is interposed between the three ends, while the spline part 5
A ring-shaped recess 53C is provided in the outer diameter part 53b of the cylindrical part on the other axial end side of the shaft 51, and an O-ring 56 is interposed in the ring-shaped recess 53C to seal the space between the inner diameter part 51b of the shaft 51 and the inner diameter part 51b of the shaft 51.

In the above conventional means, since the spline portion 529 54 (7) is sealed with O-rings on the outside of both ends in the axial direction, the length L between the driven flange and the end of the shaft engaging portion becomes large, and the driven flange 53 is This causes the wheel bearings to be unevenly distributed on the inside, in other words in the axle direction, and the wheel bearing position approaches the wheel center.Therefore, it is necessary to increase the strength and rigidity of the hub, axle, bearings, etc.If you try to avoid this, It is necessary to move the bearing away from the center of the wheel, and if the driven flange is moved to the left in the diagram, the axle support part will become larger in the axial direction.This is caused by the oil seal, so improvement is desired.

The present invention has been made to meet the above-mentioned problems, and its object is to extend a cylindrical holder so as to wrap it from the inner diameter part of the gear shaft to the inner diameter part of the driven flange cylinder part.
A seal member is interposed between the outer diameter part and the inner diameter part of the driven flange cylindrical part, and the length between the seal member between the engaging parts and the seal member is shortened as much as possible, and the entire axial direction It is an object of the present invention to provide a sealing device for a wheel drive unit of a shaft drive type motorcycle or the like, which can reduce the length, make the drive unit more compact in the axial direction, and position the wheel bearing outward.

Next, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic side view of a motorcycle 1, in which a front fork 5 that supports a front wheel 4 is supported in a steerable manner via a head tube 3 at the front end of a frame 2, and an engine 6 is mounted at the lower front of the frame 2. A fuel tank 7 is mounted on the upper part, and a seat 8 is arranged behind the fuel tank. A rear fork 10 extends from the rear main part of the frame to support a rear wheel 9.

FIG. 2 is an enlarged sectional view of the oil seal portion according to the present invention.
Figure 3 is a diagram of the expanded cross-section of the W-wheel mine.

Ru.

In FIG. 3, 11 is a case provided at the rear end of the rear fork 1o, and an input shaft 13 having a bevel gear 12 is provided in the front part of the case 11 in the front-rear direction.
The input shaft 13 is supported and sealed by a bearing 14 and an oil seal 15. An axle 16 is horizontally mounted behind the bevel gear 12 in a direction orthogonal to the axial direction of the bevel gear 12, and one end of the axle 16 is connected to the outside of the notch 11 with a nut 17, and the other end is attached to the rear end of the other gear fork 10A. It is tied to

A sleeve-shaped gear shaft 18, which is the final driven member, is loosely connected to the case side periphery on the axle 16, and this is connected to the case 11.
One end in the axial direction is rotatably supported by a bearing 19 interposed between a large-diameter stepped portion 11a provided inside the rear part and a small-diameter outer diameter portion 18a at the tip, and an oil seal is provided on the outside of the bearing 19. 20 is interposed.

A spline portion 2 is provided on the outer periphery of the large diameter intermediate portion of the gear shaft 18.
1 is provided, and this is fitted and engaged with a spline portion 22a provided on the inner diameter portion of the final bevel gear 22 on the driven side, and is coupled so as to further restrict the axial direction. The gear shaft 18 is driven by the output of the propeller shaft. Spline portion 21 of shaft 18
0 Further, a large-diameter journal portion 23 is provided on the axially inner side, and a bearing 25 is interposed between it and the opening of a cover 24 that covers the axially inner side of the case 11 to support the journal portion 23.
An oil seal 26 is interposed inside the bearing 25 in the axial direction.

A hub 9a of the rear wheel 9 is rotatably supported in the axially intermediate portion of the axle 16 by two bearings 27, 27 spaced apart in the axial direction, and a recess 9b is provided on the case side of the hub 9a. The elastic body 29 of the driven flange 28 interposed on the axle between the shaft 18 and the shaft 18 is engaged with the recess 9b. The base of the driven flange 28 is provided with a sleeve portion 30 that extends outward in the axial direction, while the inner diameter portion 31 of the journal portion 23 is made large in diameter, and the sleeve portion 30 is fitted into the inner diameter portion 31 in the axial direction. Both are engaged by spline portions 30a and 31a provided respectively. The spline portion 30a has a flattened shape.

An O-ring 32, which is a tooth sealing material, is interposed in a ring-shaped space S formed between one axial end of the shaft 31a and the driven flange 28 side end to seal the driven flange and one end of the shaft. do.

A small diameter inner diameter portion 33 is provided in a step-like manner outward in the axial direction −4 of the large diameter inner diameter portion 31 having the spline portion 30a of the shaft 18,
The tip 34a of the cylindrical holder 34 is connected to this by engaging, etc., and the base is provided with a groove 35 that is concave in the inner diameter direction and opens radially outward, and the groove 35 is formed in a ring shape. and an O-ring 36 forming an oil seal is fitted into this groove 35,
The outer diameter part of the O ring 36 is brought into contact with the inner diameter part 37 of the sleeve portion 30 of the driven flange 28.
The ring 36 has spline engagement parts 30a, 31a
abutting against the inner diameter portion 37 while lapping with this in the inner diameter direction,
Seal this side. Thus, the spline engagement parts 30a and 31a are sealed with the O-rings 32 and 36, and the "second work" is completed.
;: 工、'v Hy: 4j'A/、3. . t7. V-
Showing the chiarm.

As is clear from the above, according to the present invention, the spline portions of the driven plate and gear shaft that are engaged with each other are sealed by wrapping the spline portions at one end between the spline portions and in the inner diameter direction of the spline. The axial length between the wheels is shortened as much as possible, thereby increasing the axial distance between the wheel bearings, and thus making it possible to place the bearings as far as possible from the center of the wheel. There is no need to increase the strength and rigidity of hubs, bearings, etc. beyond what is necessary in the past, and secondly, gear shafts,
This has many advantages, such as the ability to shorten the driven flange base in the axial direction as much as possible, thereby reducing the width of the case at the rear of the rear fork as much as possible, making it more compact in the width direction.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and Fig. 1 is a schematic side view of a motorcycle, and Fig. 2 is an enlarged sectional view of a seal portion.
-1 Fig. 1 is a developed cross-sectional view of the wheel drive section, and Fig. 4 shows σN and Xl as in Fig. 2 of the conventional example. 111- In the drawing, 12.22 is a gear, 18 is a final driven member, 28
is a driven flange, 30a and 31a are engaging portions, 32,
36 is a sealing material, and 34 is a holder. Patent Applicant: Honda Motor Co., Ltd., Patent Attorney, Part 1)

Claims (1)

[Claims] The outer diameter of the base cylindrical portion of the driven flange that drives the wheels, and includes an axle disposed in a direction orthogonal to the gear driven by the propeller shaft, and a gear that is loosely engaged with the axle and meshes orthogonally with the gear. A final driven member is provided with an inner diameter engagement part that engages with the engagement part, and a sealing material is interposed at the driven flange side end in the axial direction between each engagement part, and the driven flange is inserted from the inner diameter part of the driven member. 1. A sealing device for a wheel drive unit of a shaft drive type motorcycle or the like, characterized in that a sealing material is interposed between a holder wrapped around an inner diameter part of a base cylinder and an inner diameter part of a driven flange base cylinder.