| 摘要 |
PROBLEM TO BE SOLVED: To provide a self-actuated pressure reducing valve, that can reliably avoid the breakage of a downstream side piping by closing a valve body by an independent operation from an outside in the event of the trouble of the resistance increase at a sliding portion or the clogging of a first and a second passages. SOLUTION: If a trouble occurs, a primary operation shaft 30 and an operation machine side clutch 29 are rotated in the direction, that closes the valve manually or by the self operation of an electric operation machine 31, rotation is conveyed into a valve side clutch 28 and a secondary operation shaft 27 to rotate the shaft in the direction that closes the valve, and concurrently a bevel gear 25, a bevel gear 24 and an internal thread top 23 are rotated in the direction that closes the valve, thus lowering a valve rod 12 to close a valve bore 3 with a valve body 4. Thereby, the situation is reliably avoided surely where the pressure in a secondary side B exceeds the design value for the downstream side piping and breaks the downstream side piping. COPYRIGHT: (C)2003,JPO
|
