초록 ▼

A gas flow bellows valve of low profile, low purge volume and high gas flow includes an externally pressurized bellows surrounding a stepped valve stem. A self-centering toroidal guide seals in line contact with the main valve body and a bonnet with the valve stem being translatable therein. A valve

A gas flow bellows valve of low profile, low purge volume and high gas flow includes an externally pressurized bellows surrounding a stepped valve stem. A self-centering toroidal guide seals in line contact with the main valve body and a bonnet with the valve stem being translatable therein. A valve actuator includes a valve piston connected to the stem and positioned between a pair of recesses in an actuator base and an actuator removable cap. A flat wave spring is positioned in one or the other of the recesses to alternatively bias the piston and stem to a valve normally closed or a valve normally open condition. Alternatively the spring may be removed entirely and the valve can function as a double-acting valve controlled by air pressure ports in the actuator base extending to one recess and in the actuator cap extending to the other recess. A relatively large diameter valve seal extends from the bottom end of the stem and seals in a closed position on a large diameter valve seat at the bottom of a central valve cavity. Fluid inlet and outset passages with smooth transition sections allow for fluid passage through a relatively large flow orifice between the stem seal and valve seat adjacent to the inlet and outlet passages.

대표청구항 ▼

A bellows valve comprising: a metal valve body having an inlet passage, an outlet passage, a valve cavity in fluid communication with said passages, and a valve seat in said cavity interfacing between said passages; a translatable cylindrical valve stem, on end which is selectively cooperable with t

A bellows valve comprising: a metal valve body having an inlet passage, an outlet passage, a valve cavity in fluid communication with said passages, and a valve seat in said cavity interfacing between said passages; a translatable cylindrical valve stem, on end which is selectively cooperable with the valve seat to control the flow of fluid between the said passages, and another end of which is directly linked to an actuator assembly; a bellows surrounding a portion of a lower diameter of said stem for isolating and sealing said stem from a system fluid passing through the valve chamber, such that the system fluid exerts an external compressive force on said bellows; said valve cavity having an open end to accept said stem and said bellows; wherein said actuator assembly is removably connected to said valve body and directly communicates with said stem and includes a positive linkage including an actuator piston connected to said valve stem and a flat spring of the wave or belleville type abutting an operating surface of said piston to control system fluid flow through the valve seat in one direction by the application of pressure to an actuator inlet port, and in the other direction by a force exerted in a return direction by said flat spring; and further including guide means for one-piece construction for centering and sealing said stem, said guide means surrounding and spaced from said valve stem and positioned in sealing contact between said valve body and a metal valve bonnet surrounding an upper diameter of said stem.