JPH02393Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a breather mechanism in a final gear case of a shaft drive type motorcycle.

[Conventional technology]

As is well known, a shaft drive is a method that transmits the driving force of the engine to the drive wheels via a propeller shaft, pinion gear, ring gear, etc. Usually, the parts where the pinion gear and ring gear mesh are divided into semi-tight sections. and oil is injected there for lubrication.

Fig. 1 shows a part of a shaft drive type motorcycle, in which a propeller shaft 2 connected to an output shaft of a transmission is disposed within one arm 1A of a rear fork indicated by 1 in the figure. This propeller shaft 2 is connected to a pinion gear 3 via a propeller shaft joint and a spherical spline. The pinion gear 3 is meshed with a ring gear 4 arranged perpendicularly thereto, and the ring gear 4 is connected to a rear wheel 6 via a boss member 5. Therefore, the output of the engine is sequentially transmitted to the propeller shaft 2, pinion gear 3, ring gear 4, boss member 5, and rear wheel 6.

The pinion gear 3 and ring gear 4 are housed in a final gear case 7, which includes a case body 8 and a case cover 1 that closes the rear wheel side opening 9 of the case body 8.
It is composed of 0. Lubricating oil is injected into the final gear case 7, and a breather mechanism 11 is provided in the upper part of the case body 8 (see FIG. 2).

The breather mechanism 11 is connected to the final gear case 7
The communication path 12A provided in the upper part of the case body 8, the communication path 12B provided in the case cover 10, and the communication path 12
The cap 13 covers the outer opening of the case 7 to prevent water, mud, etc. from entering the case 7 (see FIG. 3).

Note that 14 and 15 are seal members, respectively.

[Problem that the invention attempts to solve]

By the way, in the case of the breather mechanism of the final gear case as described above, since the outer opening portion of the communication passage is provided in the case body 8 which is exposed to the outside, the breather cap 13 is exposed to the outside and the appearance is deteriorated. It had the disadvantage of being damaged.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a breather mechanism for a final gear case of a motorcycle in which the breather cap is not exposed to the outside and the appearance is not impaired.

[Means for solving problems]

In order to achieve this object, the present invention has a configuration in which a chamber communicating with the inside of the case is provided at the joint between the final gear case body and the case cover, and a communication path is provided in the case cover to communicate the chamber with the atmosphere.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 4 to 6. In addition, in these figures, the conventional example shown in FIGS. 1 to 3 above, and
Identical components are given the same reference numerals.

FIG. 4 shows a final gear case equipped with a breather mechanism according to the present invention. In this example, the final gear case body 21 and the case cover 22 are
A chamber 23 is provided at the joint portion with the rear wheel axle 24 so as to extend in the circumferential direction with the rear wheel axle 24 as the center. The chamber 23 is a peripheral wall portion 2 of the case body 21.
It is formed by cutting the center of 1a inward, and as shown in FIG.
It communicates with the internal space of the final gear case 7.

Furthermore, a communication passage 26 communicating with the chamber 23 is formed in the upper part of the final gear case cover 22, as shown in FIG.
A rubber pipe 27 is inserted through. The pipe 27 is disposed such that its proximal end is inserted into the chamber 23 and its distal end protrudes from the case cover 22 to the outside. Also, pipe 27
is provided with an outer flange 28, which is held between the case body 21 and the case cover 22 to prevent the pipe 27 from coming off. Further, a collar 29 is fitted into the pipe 27 to bring the outer circumference of the pipe 27 into airtight contact with the inner surface of the communication passage 26 of the case cover 22. It is prevented from coming off by 30. Further, a cap 31 is fitted to the tip of the pipe 27. Thus, the communication path 25, the chamber 23,
A breather mechanism 32 is constituted by a pipe 27 inserted into the communication passage 26 and a cap 31.

According to the above-described breather mechanism, since the outer opening of the breather passage is provided in the case cover 22 which is not visible from the outside, the cap 31 covering the opening is also not visible from the outside, improving the appearance. can be achieved.

Further, a chamber 23 is interposed between the inside of the final gear case 7 and the breather passage outlet,
After the atmosphere is introduced into the chamber 23, the air inside the chamber 23 is allowed to enter and exit the final gear case 7, so it is possible to realize a breather with excellent cushioning effect and prevent oil leakage from the breather outlet. Can be suppressed.
Further, since the chamber 23 is provided so as to extend in the circumferential direction so as to be able to follow the wall portion 21a of the case main body 21, there is an advantage that the volume can fluctuate greatly.

In addition, in the above embodiment, the case body 21
Although the chamber 23 is provided by recessing the case cover 22, the chamber 23 may be formed by recessing the case cover 22.
It is also possible to make the chamber 23 larger by recessing both sides.

[Effect of idea]

As explained above, according to the present invention, at the joint between the final gear case body and the case cover,
A chamber that communicates with the inside of the final gear case is provided extending in the circumferential direction, and a communication path that communicates the chamber with the atmosphere is provided in the case cover.
The breather cap is not exposed to the outside, and the appearance can be improved. Further, as described above, since the chamber is interposed in the middle of the breather passage, it is possible to realize a breather with an excellent buffering effect, and it is possible to suppress oil leakage from the breather outlet.

[Brief explanation of the drawing]

Figure 1 is a partially cutaway plan view showing one conventional example;
3 is a sectional view taken along line - in FIG. 2, FIG. 4 is a side view showing an embodiment of the present invention, and FIG. 5 is a sectional view taken along line - in FIG. 4. FIG. 6 is a sectional view taken along the - line in FIG. 4. 1... Rear fork, 1A... Arm, 2...
Propeller shaft, 3... Pinion gear, 4...
Ring gear, 9... Opening, 21... Final gear case body, 22... Final gear case cover, 23... Chamber, 25... Communication path, 26
...Communication path, 27...pipe, 31...cap, 32...breather mechanism.

Claims (1)

[Scope of utility model registration request] A final gear case body disposed on one side of the rear wheel, in which a pinion gear and a ring gear are disposed in mesh with each other, and oil for lubricating these gears is sealed; and a final gear case body on the rear wheel side of the final gear case body. In the final gear case for a motorcycle, the final gear case includes a case cover that closes an opening provided in the final gear case, and a chamber extending in the circumferential direction and communicating with the inside of the final gear case is provided at a joint portion of the final gear case body and the case cover. A breather mechanism in a final gear case of a motorcycle, wherein the case cover is provided with a communication path that communicates the chamber with the atmosphere.