Abstract: In one embodiment a system is disclosed that includes an actuation device coupled with a turbomachinery mechanism. The actuation device can include multiple fluid pathways and a valve to alternatively place each of these pathways in fluid communication with a supply port while another of the pathways is in fluid communication with a return port to selectively move an actuation member along a range of travel. A brake valve may also be included to provide pressurized fluid to the actuation member when the actuation device is in an on condition and divert at least a portion of the pressurized fluid away from the actuation member through another pathway when the actuation device is in an off condition. A fluid-powered brake is coupled to this further pathway to selectively apply braking force to the actuation member in response to the diverted pressurized fluid.

Abstract: In one embodiment a system is disclosed that includes an actuation device coupled with a turbomachinery mechanism. The actuation device can include multiple fluid pathways and a valve to alternatively place each of these pathways in fluid communication with a supply port while another of the pathways is in fluid communication with a return port to selectively move an actuation member along a range of travel. A brake valve may also be included to provide pressurized fluid to the actuation member when the actuation device is in an on condition and divert at least a portion of the pressurized fluid away from the actuation member through another pathway when the actuation device is in an off condition. A fluid-powered brake is coupled to this further pathway to selectively apply braking force to the actuation member in response to the diverted pressurized fluid.