| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a flow passage open/close valve surely which can fully shut a ball valve even when a fitting part of a shaft and the ball valve loosens, and a control method for shaft rotation applied to the flow passage open/close valve. <P>SOLUTION: The flow passage open/close valve 10 includes the ball valve 14 having a through gas passage 42, a body 12, the shaft 46 to rotate the ball valve 14 in a communication chamber 26, a valve pressing member 16 that is movably connects the ball valve 14, a valve seat 18 on which the ball valve 14 is mounted, and a wave washer 32 to press the valve pressing member 16 to the ball valve 14 side. The difference between a fully closing range which is an angle range from a fully closed position of the ball valve 14 to an opening start position of the gas passage 42, and an idle angle where the rotating shaft 46 does not rotate the ball valve 14 due to loosening of the shaft 46 and the ball valve 14 in the fitting part 47, is designed to be larger than a reference angle range set in advance. <P>COPYRIGHT: (C)2012,JPO&INPIT |
