Magnetic fluid seal

Abstract

Provided is a magnetic fluid seal that cools a seal film via a magnetic pole member even when heat is transmitted from a rotating shaft to the seal film, and in which the seal film has a long servicelife. The magnetic fluid seal 1 comprises: an outer cylinder member 3 in which a rotating shaft 2 that extends from a housing for a fluid machine is accommodated; magnetic pole members 6A, 6B that areaccommodated in the outer cylinder member 3, that are arranged around the rotating shaft 2, and that form a magnetic circuit; and a seal film M that is magnetically connected on the magnetic circuit,that is arranged between the magnetic pole members 6A, 6B and the rotating shaft 2, that comprises magnetic fluids 10A, 10B, and that is formed in the axial direction. The magnetic fluid seal 1 additionally comprises an air supply path 19 that causes a gas from the exterior to flow out toward the magnetic pole members 6A, 6B.

Description

technical field [0001] The present invention relates to a magnetic fluid seal for use, for example, in high temperature environments. Background technique [0002] Conventionally, a magnetic fluid seal is known as a long-life and clean high-performance seal. This magnetic fluid seal is widely used in the manufacturing process of semiconductors and liquid crystals that require maintenance-saving and clean environments, and various coating and etching processes for them. [0003] The magnetic fluid seal seals the gap between the casing of the fluid machine and the rotary shaft with a sealing film formed of magnetic fluid formed between the magnetic pole member held fixed to the casing of the fluid machine and the rotary shaft. on the inside of the outer cylinder member. [0004] Although a sealing film is formed on these magnetic fluid seals, when the fluid sealed in the fluid machine is, for example, a high-temperature gas, heat is conducted from the high-temperature gas to...

AI Technical Summary

Problems solved by technology

[0004] Although a sealing film is formed on these magnetic fluid seals, when the fluid sealed in the fluid machine is, for example, a high-temperature gas, heat is conducted from the high-temperature gas to the outer cylinder member, and the temperature of the magnetic pole member inside the outer cylinder member The temperature of the sealing film of the magnetic fluid rises gradually, and if the temperature rises too much, the base liquid of the magnetic fluid may evaporate and the sealing property of the sealing film cannot be maintained.

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