| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve control accuracy of a flow rate, and to improve sealability between a valve member and a valve seat, while having the bidirectional relief function. <P>SOLUTION: A flow control valve 38 includes first to third valve members 96, 97 and 98 for opening/closing a fluid passage 94 of a valve housing 70, springs 118, 112 and 103 for urging the respective valve members, and a step motor 53 for opening the first valve member 96 and the second valve member 97 stepwise, and is constituted so that the second valve member 97 or the third valve member 98 is opened by differential pressure between upstream side internal pressure and downstream side internal pressure. Seal members 120, 122b and 122c are provided between the valve members 96, 97 and 98 and the valve seats 97b, 98b and 100. The seal members 120, 122b and 122c and the springs 118, 112 and 103 for urging the valve members 96, 97 and 98 corresponding to the respective seal members, are arranged with the positional relationship corresponding to the axial direction. <P>COPYRIGHT: (C)2012,JPO&INPIT |
