Patent ID: 6450477
Filing Date: 2002-09-17
Classification: F16K

Abstract:
A valve actuator for moving a valve gate between open and closed valve positions within a valve body, said valve actuator comprising:an operator assembly including: (a) an operator housing defining a pressure chamber therein and having a fluid entry port; and (b) an operator member within said operator housing movable toward said valve body in response to pressurized fluid introduced into said operator housing pressure chamber through said fluid entry port; and a bonnet assembly including: (a) a bonnet housing securable to said valve body, said bonnet housing having a bonnet housing bore therethrough; (b) an elongated bonnet stem having first and second ends, said stem being axially movable in said bonnet housing bore, unconnected at said first end to said operator member and securable at said second end to said valve gate for moving said valve gate to said open and closed valve positions; (c) a spring for producing a biasing force opposing axial movement of said operator member toward said valve body; (d) a contact member, separate from said operator member, having an outer flange, and rotatably and axially affixed to said first end of said bonnet stem, and having a surface facing said operator member for drive contact with said operator member; (e) an upper spring retainer coaxially surrounding said bonnet stem and having an inner flange for engagement with said outer flange to transmit said biasing force to said bonnet stem and to receive said movement of said operator member toward said valve body; (f) a lower spring retainer coaxially surrounding said bonnet housing; and (g) securing means for longitudinally securing said operator housing to said bonnet housing, said securing means permitting removal of said operator assembly from said bonnet assembly leaving the bonnet assembly intact to hold said valve closed when said operator assembly is removed.