US Patent 7287595 Electric-hydraulic power unit

The present invention is directed to an electric-hydraulic power unit. In one illustrative embodiment, the power unit comprises a body having a movable pressure barrier positioned therein, the movable pressure barrier defining first and second chambers therein, a configurable flow path in fluid communication with the first and second chambers, and at least one valve for configuring the flow path in a first state wherein fluid may flow within the flow path only in a direction from the first chamber toward the second chamber, and a second state wherein fluid within the flow path may flow in both directions between the first and second chambers.