Actuator having Belleville washer configuration operating in concert with a piston cylinder member

A fluid pressure actuator for a valve having a housing and an actuating stem, comprising:

• an annular housing having a closed end and an opposed open end;
• an annular connecting member secured to said open end of said annular housing, said annular connecting member having a radial flange portion connectable to said open end of said annular housing and an axially extending portion connectable to the valve housing;
• means for securing said radial flange portion to said open end of said annular housing comprising an annular groove in the bore of said annular housing, and a C-ring engaged in said groove;
• a cylindrical piston element concentrically formed on said closed end and extending into the interior of said annular housing toward said open end;
• a cup-shaped cylinder slidably and sealably mounted on the exterior of said cylindrical piston element and defining an annular space between its exterior surface and the interior bore of said annular housing;
• a radially outwardly projecting shoulder on the open end of said cup-shaped cylinder;
• conduit means in said cylindrical piston element for supplying pressured fluid to the interior of said cylinder to urge same toward the valve;
• resilient means mounted in said annular space between said radial flange portion and said shoulder to oppose the fluid pressure produced movement of said cylinder;
• and means on said cylinder for connection to the actuating stem of the valve.