Energy Recapture System for Hydraulic Elevators

摘要

In a method of driving a hydraulic system, a contracting force is applied to a hydraulic actuator, thereby causing hydraulic fluid from the hydraulic actuator to flow through a first hydraulic pump motor into a first accumulator, thereby causing the first hydraulic pump motor to apply rotational energy to a shaft. The rotational energy from the shaft is applied to a second hydraulic pump motor, thereby causing hydraulic fluid to be pumped from a second accumulator to a third accumulator so as to store energy in the third accumulator. Once energy is stored in the third accumulator, the second hydraulic pump motor is driven with hydraulic fluid stored in the third accumulator so as to apply rotational energy to the shaft, thereby driving the first hydraulic pump motor to pump hydraulic fluid from the first accumulator to the hydraulic actuator, thereby applying an expanding force to the hydraulic actuator.

主权项

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.