JPH0723660Y2 - Lip seal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an improvement of a lip-type seal for sealing the circumference of a rotating shaft.

[Conventional technology]

Conventionally, for example, instead of the mechanical seal 2, the mechanical seal 2 shown in FIG. 5 is provided on the inner circumference of the housing 6 in which the mounting space 4 is set on the assumption that the mechanical seal 2 shown in FIG. 4 is mounted. The lip type seal 8 may be mounted, and in this case, generally, the axial length l of the outer peripheral fitting portion of the lip type seal 8 is shorter than the axial length L of the mounting space 4 of the mechanical seal 2. Therefore, in order to stabilize the fixed state of the lip seal 8, a cylindrical spacer 10 or the like is interposed between the front surface of the lip seal 8 and the radial wall surface (front plate 14) of the housing 6, or It was necessary to change the design of the housing 6 to significantly reduce the axial length L of the mounting space 4. When the cylindrical spacer 10 is interposed, the lubricating oil flowing from the sealed space S through the lubricating oil supply port 20 of the housing 6 is supported by the sliding portion of the lip type seal 8 and the front plate 14. There was a problem that the supplied bearing 16 could not be sufficiently supplied.

[Problems to be solved by the device]

In view of these problems, the present invention provides a lip-type seal whose outer peripheral fitting portion is shorter than the axial length of the seal mounting space set in the housing without impairing the lubricity of the sliding portion and the bearing. The problem was to make it possible to attach stably.

[Means for Solving the Problems]

In order to solve the above-mentioned problems, the lip-type seal according to the present invention is provided with a bearing for supporting the shaft on the inner circumference thereof, and communicates between a sealed space inside the bearing in the axial direction and a mounting space outside the bearing in the axial direction. A lip-type seal that is mounted in the mounting space on the inner circumference of the housing in which the lubricating oil supply port is opened, and is a metal that is tightly fitted to the inner circumference of the housing with the rear end retained. A tubular case made of metal, and a lip member having an inner diameter end held by the case and extending toward the sealed space in sliding contact with the outer peripheral surface of the shaft, and a bearing support portion in the housing projecting in the axial direction at the front end of the case. A plurality of projections, which are in contact with the radial wall surface and are arranged at predetermined intervals in the circumferential direction, are integrally formed.

[Action]

With the lip-type seal configured as described above, the tip of the protrusion extending from the front surface of the tubular case with the rear end retained against the radial wall surface on the housing side is attached to a predetermined position on the inner circumference of the housing. Since they are positioned in contact with each other, the movement in the axial direction is completely restricted. Further, since the plurality of protrusions are provided at a predetermined interval in the circumferential direction,
The lubricating oil does not hinder the flow of the lubricating oil, that is, the lubricating oil flowing from the sealed space into the mounting space through the lubricating oil supply port of the housing passes between the protrusions and the sliding portion of the lip-type seal and Sufficiently supplied to the bearing.

〔Example〕

Hereinafter, the present invention will be described with reference to an embodiment shown in FIGS.

The lip-type seal 100 according to this embodiment includes a rubber-made lip member 102 and a synthetic resin (for example, PTF) provided on the back surface thereof.
E) lip member 104, a metal backup ring 106 and a pull ring 108 provided on the back surface of the lip member 104, and a metal cylindrical case 110.
The front end 110a side is embedded and fixed to the outer diameter portion of the rubber-made lip member 102, and the rear end 110b is swaged to the inner diameter side to integrate all the above components. The outer diameter portion of the rubber-made lip member 102 extends so as to cover the outer peripheral surface of the tubular case 110, and forms a gasket portion 112 that comes into close contact with the inner peripheral surface of the housing 6 with a proper tightening margin. Further, as shown in FIG. 2, projections 114 extending in the axial direction are integrally formed in the front end 110a of the cylindrical case 110 in the circumferential direction 4 in an evenly distributed manner.

As shown in FIG. 3, the lip-type seal 100 includes a snap ring 12 fixed to an inner circumferential groove of a housing 6 and a bearing support fixed to the front surface of the housing 6 and holding a bearing 16 on the inner circumference. Front plate 14 which is the radial wall of the section
The installation space 4 in which the axial length L is longer than the axial length l of the outer peripheral fitting portion of the lip-type seal 100 by
The rubber member lip member 102 and the synthetic resin lip member 104, which are attached to the housing 6 in which is set, are inserted into the inner circumference of the housing 6 and are rotated by the bearing 16. By slidingly contacting the outer peripheral surface of the shaft 18 which is freely supported, it performs an oil-sealing function against the lubricating oil or the like in the sealed space S. The axial length l ₁ of the protrusion 114 is
The sum of the axial length l ₀ of the cylindrical case 110 and the axial length l of the mounting space 4 is set to match.

As shown in FIG. 3, in the lip-type seal 100 having the above-described structure, the gasket portion 112 is tightly fitted to the inner peripheral surface of the housing 6 in a pressure contact state, and the rear end 110b of the tubular case 110 is formed.
With the snap ring 12 retaining the shaft, the tip of the projection 114 extending from the front end 110a of the tubular case 110 is in contact with the front plate 14 as the radial wall surface on the housing 6 side, The movement to is completely regulated and a stable fixed state is achieved. Further, the housing 6 supplies lubrication oil to the bearing 16, or if the housing 6 is provided with a mechanical seal (see FIG. 4), lubrication / cooling of the mechanical seal is performed. For the purpose of the above, the lubricating oil supply port 20 that connects the sealed space S on the inner side in the axial direction of the front plate 14 and the mounting space 4 on the outer side in the axial direction is provided. Unlike the case where the cylindrical spacer is interposed as described above, the protrusion 114 extending so as to cross the mounting space 4 does not block the flow of the lubricating oil from the lubricating oil supply port 20 to the inner peripheral side. Inner diameter end 102a of member 102 and shaft 1
The outer peripheral surface of 8 and the bearing 16 are satisfactorily lubricated.

In the illustrated embodiment, the protrusion 114 is covered with the rubber film integral with the lip member 102, but the protrusion 11 made of a metal material is used.
It is needless to say that the number of the protrusions 114 and the like may be arbitrary, and the knitting and shape of each part are not particularly limited to the illustrated example.

[Effect of device]

As described above, according to the lip type seal of the present invention, in the state of being mounted on the inner circumference of the housing, the cylindrical case having the rear end prevented from slipping off has a plurality of protrusions extending from the front surface thereof having the tips of the housing bearing support portion. By abutting against the direction wall surface, it is positioned in the axial direction without obstructing the flow of the lubricating oil to the seal sliding part and the bearing, so that the spacer can be stably installed without interposing spacers or changing the design of the housing. Can be fixed.

[Brief description of drawings]

FIG. 1 is a half sectional view of an embodiment of the present invention in an unmounted state, FIG. 2 is a perspective view of the same cylindrical case, FIG. 3 is a half sectional view of the same mounted state, and FIG. 4 is a mechanical seal. FIG. 5 is a half-cut sectional view of a housing for use in a mounted state showing an example of a conventional structure. 6 …… Housing, 12 …… Snap ring 14 …… Front plate (radial wall) 18 …… Shaft, 100 …… Lip type seal 102, 104 …… Lip member 110 …… Cylindrical case, 110a …… Front end 114 …… Protrusion, S ... Sealed space

Claims (1)

[Scope of utility model registration request] 1. A housing in which a bearing for supporting a shaft is provided on the inner circumference and a lubricating oil supply port is provided for communicating between a sealed space inside the bearing in the axial direction and a mounting space outside the bearing in the axial direction. A lip-shaped seal that is mounted on the circumference of the housing in the mounting space, and is a metal cylindrical case that is tightly fitted to the inner circumference of the housing with the rear end retained, and is held by this case. And a lip member whose inner diameter end extending toward the sealed space is in sliding contact with the outer peripheral surface of the shaft, and at a front end of the case, a predetermined circumferential interval for axially projecting to abut the radial wall surface of the bearing support portion in the housing. A lip-type seal, characterized in that a plurality of protrusions are integrally formed.