JP2018128138A - Leakage preventing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a leakage that occurs at a contact part between a wall and a shaft where the shaft penetrating the wall conducts linear motion or rotational motion, the leakage occurring when a pressure difference is generated between both sides of the wall, and to prevent the leakage in a gap in the contact part between the shaft and the wall when a pressure difference is generated between both sides of the wall, since the gap is required in a slide part which is a contact part between the shaft and the wall, in order to enable the linear motion or the rotational motion of the shaft penetrating the wall.SOLUTION: For a shaft that conducts linear motion, a flange is provided on the shaft, and the flange and a wall surface hold a seal member therebetween to seal a contact part between the shaft and a wall, thereby preventing leakage. For a shaft that conducts rotational motion, a flange is provided on the shaft, and a cover for holding a seal member between it and the flange and holding the seal member between it and a wall surface is provided to seal a contact part between the shaft and a wall, thereby preventing leakage.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a leak prevention mechanism for preventing a leak when a differential pressure is generated on both sides of a wall when the shaft is not moved at a contact portion between the wall and the shaft that performs linear motion or rotational motion through the wall. .

  When transmitting a linear motion or a rotational motion from one side of the wall to the other side, the shaft is penetrated through the wall, and a bearing is provided at a sliding portion which is a contact portion between the shaft and the wall to improve the motion efficiency. In order for the shaft that penetrates the wall to move linearly or rotationally, a gap is required in the sliding part, and if it is necessary to create a differential pressure on one side of the wall and the other, the gap in the sliding part A leak occurs.

  In a vacuum container, in the case of linear motion, a bellows may be provided at the sliding portion to shut off the inside and outside of the container to prevent leakage. In the case of rotational movement in the vacuum vessel, there is a case where an electromagnetic fluid seal or a mechanical seal is provided at the sliding portion to block the inside and outside of the vessel to prevent leakage.

  However, the bellows cannot take a large linear stroke, and the bellows and the electromagnetic fluid seal are generally expensive. Mechanical seals are cheaper than electromagnetic fluid seals.

  When replacing the inside of the device with an inert gas such as nitrogen replacement in a glove box, the amount of inert gas consumed can be reduced by filling the inert gas after evacuating the inside of the device. The concentration of the active gas can be increased.

  In such an apparatus, when a shaft for transmitting a linear motion or a rotational motion is provided from the outside to the inside of the apparatus, a means for preventing leakage at the time of vacuum is required.

  However, there is a demand to reduce the cost of leak prevention means, not a vacuum device that always requires vacuum. When evacuating, the shaft for transmitting linear motion or rotational motion from the outside to the inside of the apparatus may be stopped.

JP-A-8-261333

  When a differential pressure is generated on both sides of the wall at the contact portion between the shaft and the wall where the shaft penetrating the wall is linearly or rotationally moved, there is a problem that leakage occurs at the contact portion.

  In addition, in order for the shaft penetrating the wall to perform linear motion or rotational motion, a clearance is required in the sliding portion that is a contact portion between the shaft and the wall, and if a differential pressure is generated on both sides of the wall, There is a problem that a leak occurs in a gap between walls. Here, the shaft may be stopped when the differential pressure is generated.

  In a shaft that performs linear motion, a flange is provided on the shaft, and a sealing material is sandwiched between the flange and the wall surface to seal the shaft and the wall to prevent leakage.

  In a shaft that performs rotational movement, a flange is provided on the shaft, and a seal that sandwiches the sealing material between the flange and the wall is provided, thereby sealing the shaft and the wall to prevent leakage.

1 is a schematic view of a preferred embodiment according to the present invention. 1 is a schematic view of a preferred embodiment according to the present invention.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. Note that the present invention is not limited to the embodiments described below.
1 and 2 show cross-sectional shapes.
As shown in FIG. 1, the leak prevention mechanism according to the embodiment of the present invention includes a flange 102 on a linear motion shaft 101. A sealing material 103 is provided.

  With respect to the operation from FIG. 1A to FIG. 1B, the flange 102 on the linear motion shaft 101 sandwiches the sealing material 103 between the wall surface 100 and prevents leakage.

  As shown in FIG. 2, the leak prevention mechanism according to the embodiment of the present invention includes a flange 201 on the rotating shaft 200. Sealing materials 202 and 203 and a cover 204 are provided.

  In the operation from FIG. 2A to FIG. 2B, the cover 204 sandwiches the seal material 202 between the flange 201 on the rotary shaft 200 and at the same time sandwiches the seal material 203 between the wall surface 100 and leaks. To prevent.

DESCRIPTION OF SYMBOLS 100 Wall 101 Linear motion shaft 102 Flange 103 Seal material 200 Rotating shaft 201 Flange 202 Seal material 203 Seal material 204 Cover

Claims (3)

  A leak prevention mechanism that prevents a leak by sealing the contact portion with a sealant when a differential pressure is generated on both sides of the wall at the contact portion of the shaft penetrating the wall.   The leak prevention mechanism according to claim 1, wherein when the shaft penetrating the wall performs a linear motion, a leak is prevented by providing a flange on the shaft and sandwiching a sealing material between the flange and the wall surface.   2. The leak prevention mechanism according to claim 1, wherein when the shaft penetrating the wall performs a rotational motion, a leak is prevented by providing a flange on the shaft and sandwiching the seal material with the flange and simultaneously sandwiching the seal material with the wall surface. .