Energy recovering system of hydraulic lift device for battery operated industrial trucks

摘要

An energy recovering system of a hydraulic lift device for a battery operated industrial truck. With the system, working oil can be supplied to other hydraulic actuators while energy recovering operation is performed by the hydraulic lift device, and energy recovering efficiency is increased. A hydraulic motor (6) is disposed in a fluid path for recovering pressurized working fluid from a lift cylinder (1) via a control valve (10) to a working fluid reservoir tank (8) so that the hydraulic motor (6) is driven by the pressurized working fluid returning from the lift cylinder (1). The hydraulic motor (6) is connected to an electric motor (4) for driving a hydraulic pump (3), which supplies pressurized fluid to the lift cylinder (1), by means of a one-way clutch (7) which performs torque transmission only from the hydraulic motor (6) to the electric motor (4).