Patent ID: 7347406

Claim:
A shut-off valve disposed between each opening of a pair of vacuum chambers comprising: an elongated casing having an elongated cylindrical space therein and formed with a slot at each of its opposing sides so as to be elongated in its axial direction; a valve body disposed lengthwise in the cylindrical space and having a shaft rotating around a central axis of the valve body and a communication passage penetrating therethrough in its diameter direction so as to communicate with each opening of the vacuum chambers; a drive unit for driving the valve body to rotate the shaft and provided at one end of the casing; and an open and close mechanism provided for the shaft for opening and closing each of the openings of the vacuum chambers and disposed at each of portions symmetric with respect to the central axis of the shaft, each portion of the open and close mechanism having: a sheet member which is an elongated plate-like member and having a circular-arc-shaped outer peripheral surface opposed to an inner surface of the easing for opening and closing each slot of the casing, a plurality of support columns provided at intervals on the shaft for supporting the sheet member reciprocatingly in a radial direction of the shaft, a plurality of urging members for 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 and including a plurality of the support columns and the urging members therein, the shaft being formed with an air passage communicating with the sealed space.