Energy Efficient Fluid Powered Linear Actuator With Variable Area

摘要

Hydraulic actuation systems having variable displacements and energy recovery capabilities include cylinders with pistons disposed inside of barrels. When operating in energy consuming modes, high speed valves pressurize extension chambers or retraction chambers to provide enough force to meet or counteract an opposite load force. When operating in energy recovery modes, high speed valves return a working fluid from extension chambers or retraction chambers, which are pressurized by a load, to an accumulator for later use.

主权项

1. A linear actuation system comprising:
two or more double-acting hydraulic cylinders with each hydraulic cylinder having a cylinder barrel, a cap end wall and a rod end wall that define an interior volume, the barrel surrounds a piston that partitions the interior volume into an extension chamber and a retraction chamber, the piston transfers a force to a load or absorbs a force from an external load; a low pressure valve fluidly coupling each extension chamber and retraction chamber to a low pressure reservoir; a high pressure valve fluidly coupling each extension chamber and retraction chamber to a high pressure accumulator; and wherein, when the system is configured in an energy consuming mode and the load force is in an opposite direction as an extending piston force, the high pressure valve fluidly coupling the extension chamber of an active cylinder to the high pressure accumulator and the low pressure valve fluidly coupling the retraction chamber of the active cylinder to the low pressure reservoir are configured in an open position, and the high pressure valve fluidly coupling the extension and retraction chambers of a passive cylinder to the high pressure accumulator are configured in a closed position and the low pressure valve fluidly coupling the extension and retraction chambers of the passive cylinder to the low pressure reservoir are configured in an open position, and when the system is configured in an energy consuming mode and the load force is in an opposite direction as a retracting piston force, the high pressure valve fluidly coupling the retraction chamber of an active cylinder to the high pressure accumulator and the low pressure valve fluidly coupling the extension chamber of the active cylinder to the low pressure reservoir are configured in an open position, and the high pressure valve fluidly coupling the extension and retraction chambers of a passive cylinder to the high pressure accumulator are configured in a closed position and the low pressure valve fluidly coupling the extension and retraction chambers of the passive cylinder to the low pressure reservoir are configured in an open position, and when the system is configured in an energy recovery mode and the load force is in the same direction as an extending piston, the high pressure valve fluidly coupling the retraction chamber of an active cylinder to the high pressure accumulator and the low pressure valve fluidly coupling the extension chamber of the active cylinder to the low pressure reservoir are configured in an open position, and the high pressure valve fluidly coupling the extension and retraction chambers of a passive cylinder to the high pressure accumulator are configured in a closed position and the low pressure valve fluidly coupling the extension and retraction chambers of the passive cylinder to the low pressure reservoir are configured in an open position, and when the system is configured in an energy recovery mode and the load force is in the same direction as a retracting piston, the high pressure valve fluidly coupling the extension chamber of an active cylinder to the high pressure accumulator and the low pressure valve fluidly coupling the retraction chamber of the active cylinder to the low pressure reservoir are configured in an open position, and the high pressure valve fluidly coupling the extension and retraction chambers of a passive cylinder to the high pressure accumulator are configured in a closed position and the low pressure valve fluidly coupling the extension and retraction chambers of the passive cylinder to the low pressure reservoir are configured in an open position.