US Patent 8251184 Hydraulic load lifter with energy recovery system

Provided is a system, lifting column and method for the energy efficient lifting and lowering of a load, such as a vehicle. The system includes a lifting column having a frame with a movable carrier and a drive which acts on the carrier. The drive includes a power source for power supply to a motor, a pump in an ascent mode driven by the motor and in a decent mode driving the motor as a generator for energy-recovery, and motor control unit for control of the motor. The motor control unit is arranged such that the power supply of the motor is manipulated for speed control of the carrier in at least the ascent mode.