JP2017048819A5 - - Google Patents

Description

In order to achieve the above object, a seal structure according to the present invention is a seal structure that separates two spaces having different pressures, and is a cylindrical housing that is disposed in a space on the high-pressure side of the two spaces having different pressures. A shaft inserted into the housing, and fixed to one end of the shaft and rotated or moved in the axial direction together with the shaft, and the outer diameter surface of the shaft and the shaft are inserted into contact with the housing An annular first seal member that seals a first gap that is a gap between the housing and the through hole .

As a desirable mode of the present invention, a first gap that is fixed to the shaft with a predetermined distance in the axial direction from the first seal member and rotates together with the shaft and whose side surface is a gap of a predetermined size is provided. A seal fixing member that opposes the inner wall (inner peripheral surface) of the housing, and an annular shape that is fixed to the seal fixing member and rotates together with the seal fixing member to contact the housing and seal the first gap. The second seal member is preferably further provided.

The seal fixing portion 32 is provided with a first seal member 5. The first seal member 5 is made of, for example, a nonmetallic material such as resin or rubber. The first seal member 5 is an annular elastic member centered on the rotation center axis Zr. The first seal member 5 is fitted in the seal fixing recess 32b of the shaft 81 so as to be in contact with the inner diameter surface of the through hole 22 of the housing. The fixed portion 32 and the end surface of the body portion 331 of the movable member 33 are sandwiched and fixed. Thereby, the first seal member 5 rotates around the rotation center axis Zr together with the shaft 81 and the movable member 33. The first seal member 5 seals a gap (first gap) 15 between the outer diameter surface 82 b of the shaft 81 and the through hole 22 of the housing 2.

Sealing structure 1 according to the first embodiment, it is fixed to the sheet Yafuto 8 1 comprises a movable member (seal pressing member) 33 that rotates with the shaft 81. The first seal member 5 includes a seal flange portion 54 that protrudes radially inward of the shaft 81 and is fixed between the seal fixing portion 32 and the movable member (seal pressing member) 33.

In the second embodiment, a seal fixing member 35 is provided between the shaft 81 and the movable member 33. The seal fixing member 35 is fixed to each other by screw portions 35 a formed at both ends in the axial direction and screw holes 331 a and 35 a formed in the shaft 81 and the movable member 33. The shaft 81 side end surface of the seal fixing member 35 sandwiches and fixes the seal flange portion 54 of the first seal member 5 inserted into the seal fixing recess 32 b of the shaft 81. A seal fixing recess 35 b is formed at the end of the seal fixing member 35 in the axial direction end surface, and the flange portion 540 of the second seal member 50 inserted therein is sandwiched and fixed by the axial end surface of the movable member 33. .
In the present embodiment, the second seal member 50 is the same as the first seal member 5, but the shape and size may be different as long as they have the same configuration. For example, the outer diameter of the movable member 33 may be formed larger or smaller than the shaft 81, and the second seal member 50 larger or smaller than the first seal member 5 may be used accordingly.

According to the above embodiment, the gap between the housing 2 and the shaft 81, the movable member 33, and the seal fixing member 35 can be double sealed with the first seal member 5 and the second seal member 50. Sealing performance can be improved.

(Embodiment 3)
FIG. 5 is a cross-sectional view schematically showing a seal structure according to the third embodiment. The embodiment 2 described above is a space surrounded by the shaft 81, the inner wall of the through hole 22 , the first seal member 5, and the second seal member 50 from the gas passage 22 b formed in the middle in the axial direction of the housing 2. The point which exhausts the gas of S differs.

The gas passage 22 b is formed at an intermediate position in the axial direction of the cylindrical portion 21 </ b> A of the housing 2.
An annular groove 22a is formed on the inner wall of the through hole 22 of the cylindrical portion 21A, and a gas passage 22b is opened at the bottom of the annular groove 22a. The annular groove 22 a is formed at a position that is always located between the first seal member 5 and the second seal member 50 in the range of the axial movement of the shaft 81 relative to the housing 2.

According to the above embodiment, the space surrounded by the housing 2, the shaft 81, the movable member 33 and the seal fixing member 35, the first seal member 5, and the second seal member 50 is exhausted from the gas passage 22b. Sealing performance can be improved.

Claims (11)

A seal structure that separates two spaces having different pressures, a cylindrical housing disposed in a high-pressure side of the two spaces having different pressures, a shaft inserted into the housing, and one end of the shaft A first gap which is fixed to a portion and rotates together with the shaft or moves in the axial direction and is in contact with the housing and between the outer diameter surface of the shaft and the through hole of the housing into which the shaft is inserted. An annular first seal member that seals the gap.   The first seal member includes a seal flange portion that protrudes radially inward of the shaft, is fixed to the shaft and one end of the shaft, and is sandwiched and fixed by a rotating member that rotates together with the shaft. The seal structure according to claim 1. Wherein the first sealing member comprises a fixed part in contact with the front Symbol shaft, and the lip portion in contact with the housing, an annular connecting portion connecting the said fixed lip, claim 1 or characterized in that it comprises a 2. The seal structure according to 2.   The seal structure according to claim 3, further comprising an urging member provided in a space surrounded by the lip portion, the annular coupling portion, and the fixing portion, and pressing the lip portion against the housing. .   The space surrounded by the lip portion, the annular connecting portion, and the fixed portion opens toward a high-pressure side space among the two spaces having different pressures. Or the seal structure of 4. Wherein the first sealing member and the axial direction with a predetermined gap being secured to said shaft and rotates with the shaft, and side surfaces having the first gap is a gap of predetermined size of the housing A seal fixing member facing the inner wall; and an annular second seal member that is fixed to the seal fixing member and rotates together with the seal fixing member, contacts the housing, and seals the first gap. The seal structure according to any one of claims 1 to 5, characterized in that:   An exhaust hole for exhausting a space surrounded by the inner peripheral surface of the housing, the first seal member, the second seal member, and the outer peripheral surface of the shaft is formed in the housing. Item 7. The seal structure according to any one of Items 1 to 6.   A rotation drive device comprising the seal structure according to claim 1 and an electric motor that rotates the shaft.   A transport apparatus comprising: the seal structure according to claim 1; and a movable member that moves an object to be transported, wherein the rotation of the shaft is interlocked with the movable member.   A machine tool comprising the seal structure according to any one of claims 1 to 7.   A semiconductor manufacturing apparatus comprising the seal structure according to claim 1.