METHOD FOR CONTROLLING SWING MOTOR IN HYDRAULIC SYSTEM AND HYDRAULIC SYSTEM

摘要

The present disclosure relates to a method for controlling a swing motor in a hydraulic system and a hydraulic system. The method for controlling the swing motor in the hydraulic system and the hydraulic system according to the exemplary embodiment of the present disclosure may ensure the sufficient amount of hydraulic oil in a make-up line in a situation in which the hydraulic oil needs to be supplementarily supplied to the swing motor in the hydraulic system. Therefore, it is possible to prevent the occurrence of cavitation in the swing motor by stably supplying the amount of hydraulic oil at the point in time where the hydraulic oil needs to be supplementarily supplied to the swing motor. In addition, it is possible to prevent the occurrence of abnormal noise which is harsh to the ear when the cavitation occurs.

主权项

1. A method for controlling a swing motor in a hydraulic system, the hydraulic system comprising:
a main pump which discharges hydraulic oil; an auxiliary pump which discharges pilot hydraulic oil; a control valve unit which is disposed on a hydraulic line connected to the main pump and is controlled to supply the hydraulic oil to the swing motor; a bypass cut valve which is disposed on the hydraulic line at a downstream side of the control valve unit and is closed when the pilot hydraulic oil discharged from the auxiliary pump is supplied; a bypass control valve which is controlled to connect the auxiliary pump and the bypass cut valve in an ON state, and to disconnect the auxiliary pump from the bypass cut valve in an OFF state; a joystick which is operated to supply the pilot hydraulic oil to the control valve unit; and a control unit which controls the bypass control valve, wherein the bypass control valve is controlled such that after the bypass control valve is maintained in the ON state during a first delay time D1 from a point in time t1 where a first pressure Ps is formed in a pilot line by the operation of the joystick, the state of the bypass control valve is changed to the OFF state, after the first delay time D1 has passed, the state of the bypass control valve is changed from the OFF state to the ON state at a point in time t3 where the pressure formed in the pilot line is decreased and reaches a second pressure Pe lower than the first pressure Ps, and then the bypass control valve is maintained in the ON state during a second delay time D2.