Abstract: A positive displacement pump (8) comprises a cylindrical input shaft (13) comprising a first area (A1) with a first diameter (D1), a second area (A2) with a second diameter (D2), and a third area (A3) with a third diameter (D3), where the second diameter is greater than the first diameter and the third diameter. A stator (19) is press fit to a portion of the third area. A cylindrical bushing (15) is press fit around the second area. When the input shaft (13) rotates, the torsional vibration damping bushing (15) resists the rotation. The pump also comprises a clutch assembly (21). A clutch armature (29) of the assembly comprises a cylindrical, hollow passageway (290) and radially extending arms (39). Each arm comprises an opening (293), at least one slot (295) passing through the arm, and at least one void (297) abutting the slot, the void passing through the arm. When the clutch assembly engages, the armature damps vibrations.

Abstract: A fluid pressure actuator assembly (44) adapted for use with a valve member (42) is disclosed, the actuator being of the type comprising a housing assembly (50), and an axially moveable diaphragm assembly (56). A linkage member (48) is operably associated with said diaphragm assembly and extends axially through a linkage opening (70), and is connected to a valve member (42). A preload member (74) includes a generally annular preload portion (76) between a stop surface (55) and the diaphragm assembly (56), and in engagement with both. The preload portion (76) maintains the diaphragm assembly (56) in a position corresponding to a first position of said valve member (42), in opposition to the force of a biasing means (68).