摘要 |
A shut-off valve disposed between openings formed to a vacuum chamber includes a casing, a valve body disposed inside the casing and having a shaft rotating around a central axis of the valve body, a drive unit for driving the valve body to rotate the shaft, and an open/close mechanism provided for the shaft for opening and closing each of the openings. The open/close mechanism includes a sheet member mounted to the shaft so as to protrude outward in a radial direction of the shaft to thereby close each of the openings, an urging member urging the sheet member inward or outward in the radial direction of the shaft, and a seal member connected to the sheet member so as to be associated therewith and forming a sealed space between the sheet member and the shaft, which is formed with an air passage communicating with the sealed space.
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