| 摘要 |
PURPOSE:To maintain the discharge rate of the hydraulic pump constant in such a way that a pump motor is driven at almost constant speed with the power source which has been controlled so as to generate nearly a constant voltage at more than the revolving speed of an engine at the working time at least driven by means of the engine. CONSTITUTION:A power generator G is set to be revolved and driven through a proper transmission gear 2 by means of an engine 1. When the revolving speed of the engine 1 exceeds the determined speed N1, generating voltage of the power generator G is made to be nearly constant by driving a voltage regulator R, and the output side of the voltage regulator R is connected through an open- circuit switch S to a pump motor M. In consequence, at the working time, since the output voltage of the voltage regulator R becomes nearly constant, discharge rate characteristics per unit time of the pressure oil in the pump motor M, namely in the hydraulic pump P becomes almost constant likewise. |
