Patent ID: 8429907

Claim:
A hydraulic actuation system comprising: a hydraulic power source ( 102 ) providing a hydraulic fluid and having an output; a directional control valve ( 106 ) coupled to the output of the hydraulic power source and controlling a direction of hydraulic fluid flow in the system; a hydraulic cylinder ( 108 ) coupled to the directional control valve, the cylinder receiving hydraulic fluid at a first port and expelling hydraulic fluid at a second port and moving a load ( 114 ) at a movement rate as a result of receiving hydraulic fluid; a fixed displacement motor ( 150 ) coupled the directional control valve and receiving hydraulic fluid expelled by the hydraulic cylinder, the fixed displacement motor including a drive arm ( 152 ); and a variable displacement pump ( 154 ) attached to the drive arm ( 152 ) and varying the movement rate by varying its displacement to either decrease or increase a torque applied to the drive arm ( 152 ) and having an output connected to the directional control valve.