Linear actuator for rotating shaft assemblies

摘要

A linear actuator for a rotating shaft assembly is provided that includes a cylinder member and a primary piston arranged within a cavity defined by the cylinder member. A first face of the primary piston delimits a first chamber within the cavity and a second face of the primary piston delimits a second chamber within the cavity. A rotatable shaft is fixed to the primary piston and defines a first main passage in fluid communication with the first chamber and a second main passage in fluid communication with the second chamber. A pressure delivery body is rotatably fixed to the rotatable shaft and defines a first delivery passage in fluid communication with the first main passage and a second delivery passage in fluid communication with the second main passage. The pressure delivery body further includes a passage isolation system for selectively isolating fluid communication between the first delivery passage and the first main passage and fluid communication between the second delivery passage and the second main passage. Fluid pressurization of the chambers actuates the rotatable shaft in an axial direction. A pressure limiting system is employed for selectively blocking fluid communication through the first main passage and the second main passage. Blocking fluid communication through the main passages substantially maintains fluid pressurization in the chambers.