Patent ID: 7231763
Filing Date: 2007-06-19
Classification: F03D,F05B,F15B,Y02E,Y02P

Abstract:
1. A hydraulic system for supplying an operating oil to a predetermined load, comprising: an oil pressure source capable of outputting a predetermined hydraulic power; a first oil path one end of which is connected to the oil pressure source; a hydraulic pump motor having an inlet port to which the other end of the first oil path is connected; an inertial body connected to a rotary shaft of the hydraulic pump motor; a second oil path one end of which is connected to an outlet port of the hydraulic pump motor; an unloading oil path branched from the second oil path; an on-off valve inserted in the unloading oil path; a valve for preventing backflow of the operating oil to the unloading oil path, which is connected to the other end of the second oil path; and a third oil path extending from the valve and connected to the load; and a controller for controlling opening and closing of the on-off valve, wherein when the on-off valve is closed and a torque for driving the oil pressure source is smaller than a torque occurred by the pump motor, the controller is operative to exercise control for repeatedly switching the on-off valve so as to increase the discharge pressure of the pump motor and supply the oil from the pump motor toward the load.