JPS6039574Y2 - Transmission breather - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a breather for a transmission device in which a clutch, a speed reducer, etc. are built into a casing.

This type of transmission is equipped with a breather to ensure air circulation with the outside in order to prevent the inside of the casing from heating up and becoming pressurized during operation. There is a problem in that oil leaks outside from this breather because the oil is agitated or scattered.

For this purpose, various shapes of breathers have been devised, but none of them can reliably prevent oil leakage.

This invention was made in view of the above circumstances, and is intended to provide a breather that can eliminate leakage of oil inside the casing to the outside.

Hereinafter, embodiments of this invention will be described in detail based on the drawings.

The drawing shows a part inside the casing of the transmission.

Inside the casing 9, there is a rotation direction switching clutch, a speed reducer (
(all not shown) and other power transmission mechanisms are housed therein.

A gear 2 fixed to the rotating shaft 1 is, for example, an intermediate gear, and a gear attached to the shaft of the rotational direction switching clutch and a gear provided on the input side of the reducer mesh with each other via this gear 2. .

The rotating shaft 1 is rotatably supported by bearings 7 and 8 provided on a support portion projecting inward from a casing 9.

One end 1a of the shaft 1 is located near the inner surface of the casing 9, and the other end 1b is located near the center within the casing 9.

This rotating shaft 1 has a shaft 1 from one end 1a to the other end 1b.
An air circulation hole 3 passing through the center of the shaft and extending in the axial direction is formed, and both ends of the shaft 1 are open.

The inner diameter of the air circulation hole 3 is smaller at one end 1a, larger at the other end 1b, and gradually increases from the one end 1a toward the other end 1b.

A breather opening 4 is provided in the casing 9 at a position opposite to the end surface of one end 1a of the rotating shaft 1.

The opening at one end 1a of the air circulation hole 3 of the rotating shaft 1 faces the breather opening 4 across a small space 6 between the casing 9 and the bearing 7.

An air circulation pipe 5 opened to the outside is connected to the breather port 4.

This flow pipe 5 is equipped with a filter and the like.

In the above configuration, when the inside of the casing 9 is heated and pressurized by the operation of the power transmission mechanism, the air inside the casing 9 is passed through the air circulation hole 3 of the rotating shaft 1, through the breather port 4, and the circulation pipe 5 to the outside. leaks to.

Further, after the transmission stops operating, if the inside of the casing 9 is cooled down to a pressure lower than atmospheric pressure, the atmosphere flows into the casing 9 through the flow path opposite to the above.

In this way, the atmosphere flows into and out of the casing 9 depending on its state, and the breather function is achieved.

Lubricating oil stirred or scattered by the operation of the power transmission mechanism in the casing 9 may enter the air circulation hole 3 from the other end 1b of the rotating shaft 1 and adhere to the inner surface thereof.

However, since the rotating shaft 1 is rotating at high speed and the diameter of the air circulation hole 3 gradually increases toward the other end 1b, the oil adhering to the inner surface of the air circulation hole 3 is transferred to the other end by centrifugal force.
It moves to side b and never reaches side 1a at one end.

Therefore, oil does not leak to the outside through the breather port 4 and the air circulation pipe 5.

As described above, the breather according to this invention can sufficiently perform the function as a breather and can prevent oil leakage in the casing of the transmission device.

Furthermore, the structure is extremely simple and can be easily installed.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of this invention. DESCRIPTION OF SYMBOLS 1... Rotating shaft, 1a... One end of the rotating shaft, 1b... Other end of the rotating shaft, 3... Air circulation hole, 4... ...breathing port, 9...casing.

Claims (1)

[Scope of utility model registration request] A predetermined rotary shaft, one end of which extends close to the inner surface of the casing of the transmission device, is formed with an air circulation hole in the axial direction from one end to the other end, and the inner diameter of the air circulation hole extends from the one end to the other end. 1. A breather for a transmission device, characterized in that the breather gradually increases in pressure, and has a breather opening leading to the outside of the casing near the opening at one end.