|국가/구분||United States(US) Patent 등록|
|미국특허분류(USC)||137/219 ; 251/282|
|§371/§102 date||19980708 (19980708)|
|발명자 / 주소|
|대리인 / 주소||
|인용정보||피인용 횟수 : 11 인용 특허 : 2|
In-line control valve constructions are described which include a piston-type valve assembly and a plurality of control chambers (C1,C2,C3,C4) controlled via one or more controls ports (CP1, CP2) to provide a normally-open valve may be closed by controlling the fluid pressure applied to the control port (CP1, CP2), or a normally-closed valve which may be opened by controlling the fluid pressure applied to the control port (CP1,CP2). Also described are valves which have a balanced construction and which therefore include relatively small actuators for ope...
[ What is claimed is:] [1.] An in-line control valve, comprising:a housing having an inlet port, an outlet port downstream of the inlet port, and a valve seat between said two ports;a valve assembly within said housing, said valve assembly including a valve member movable towards and away from said valve seat and having an upstream face facing said valve seat and a downstream face facing the outlet port;a valve stem fixed to the valve member and extending downstream thereof;a piston head carried by the valve stem at the downstream end thereof and having ...