PURPOSE: To provide a hydraulic system for supplying fluid from a pump in a closed center hydraulic system equipped with a load pressure sensing ability to a hydraulic function having no load pressure sensing capability.
CONSTITUTION: A hydraulic system 10 is equipped with a hydraulic pump 12, with is output port 14 fed with a pressure fluid as a function of the pressure at a load sensing port 16, a hydraulic reserver 18, and a load pressure sensing line coupled with the load sensing port. A supply control valve 40 takes either a first position, where the reserver 18 is in communication with the load sensing port or the second position where the output port of the pump is in communication with the load sensing port. When a spring 50 presses a valve member 48 to its first position and a solenoid 52 is energized, the valve member moves to its second position. The solenoid is energized, when an apparatus control valve is actuated so that the supply control valve applieds the pump pressure in communication with the load sensing port, and the pump always works with full power, when the second hydraulic function is in effect.
RARII MAABUIN DERUFUSU
DEREKU MARUKOMU IIGURUSU
RONARUDO RII PURATSUTO
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