Energy recovery system for off-highway vehicles with hydraulic transformer coupled to transmission power take-off

Abstract

An energy conserving hydraulic system for a mobile work machine includes a prime mover, a drivetrain, a baseline hydraulic system, a power-take-off, a transformer, a work implement, and an accumulator. The drivetrain may include an automated manual transmission (AMT) that is rotationally coupled to the prime mover and the power-take-off. The baseline hydraulic system is powered by the prime mover and includes a first hydraulic circuit. The transformer is hydraulically coupled to second and third hydraulic circuits. The work implement is actuated by an actuator that is adapted to be simultaneously hydraulically coupled to the first and the second hydraulic circuits. The power-take-off is adapted to exchange shaft power with the transmission. A clutch selectively rotationally couples the transmission and the power-take-off. The accumulator is hydraulically coupled to the second hydraulic circuit. The second hydraulic circuit is hydraulically coupled to a first rotating group of the hydraulic transformer, and a third hydraulic circuit is hydraulically coupled to a second rotating group of the hydraulic transformer.