Patent ID: 9605694
Date: 2017-03-28
CPC Classifications: B66B,F15B,Y02B

Claim:
1. A hydraulic system, comprising: (a) a hydraulic actuator; (b) a first accumulator; (c) a first hydraulic pump motor in fluid communication with the first accumulator and in fluid communication with the hydraulic actuator, the first hydraulic pump motor including a first shaft coupling, the first hydraulic pump motor being configurable as a motor in which rotational energy is applied to the first shaft coupling as a result of hydraulic fluid moving from the first accumulator into the hydraulic actuator, the first hydraulic pump motor also being configurable as a pump in which rotational energy received from the first shaft coupling causes hydraulic fluid to be pumped from the hydraulic actuator into the first accumulator; (d) a shaft mechanically coupled to the first shaft coupling; (e) a second accumulator; (f) a third accumulator; and (g) a second hydraulic pump motor in fluid communication with the third accumulator and in fluid communication with the second accumulator, the second hydraulic pump motor including a second shaft coupling mechanically coupled to the shaft, the second hydraulic pump motor being configurable as a pump in which rotational energy received from the second shaft coupling causes hydraulic fluid from the third accumulator to be pumped from the third accumulator into the second accumulator thereby storing energy in the second accumulator, the second hydraulic pump motor also being configurable as a motor in which rotational energy is applied to the second shaft coupling as a result of hydraulic fluid from the second accumulator moving into the third accumulator, thereby releasing energy stored in the second accumulator to be applied to the shaft.