| 摘要 |
PURPOSE:To permit maintaining a constant discharge quantity without being influenced by the variation of the discharge pressure by allowing the control pressure of the self discharge fluid to operate onto the working surfaces of operating spools through the operation of the operating spools which are operated in accordance with an outside operation pressure, thus adjusting the displacement amount of a swash plate. CONSTITUTION:A swash plate 6 is controlled to a certain inclination angle by operating a desired outside operation pressure onto the working surfaces 22a and 31a of operation spools 22 and 31 through the operation of a reducing valve 16 by switching the control pressure of the self fluid of a pump, namely switching a selector valve 63, not by operating the outside operation pressure onto a control plunger 14, and an arbitrary pump discharge quantity corresponding to said inclination angle is obtained. Therefore, even if the discharge pressure of the pump is varied through variation of a load, the inclination angle of the swash plate 6 can be kept constant, in other words, the discharge quantity can be kept constant. |
