HYDRAULIC SYSTEM FOR WORK MACHINE AND WORK MACHINE WITH THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a hydraulic system for a work machine capable of reducing a loss of horse power of a pump and provide a work machine.;SOLUTION: This invention comprises an engine 32; a first hydraulic pump P1 discharging working oil by driving the engine; a second hydraulic pump P2 different from the first hydraulic pump; a first oil passage 40 connected to the first hydraulic pump; a first takeout part 43 arranged at the first oil passage to take out working oil flowing in the first oil passage; a second takeout part 44 arranged at the first oil passage at a position different from that of the first takeout part and taking out the working oil flowing at the first oil passage; a hydraulic pressure control part 75 for controlling the second hydraulic pump on the basis of a differential pressure between the first pressure acting as a pressure of the working oil taken out of the first takeout part and the second pressure acting as a pressure of the working oil taken out of the second takeout part; a first metering part 45 arranged between the first takeout part and the second takeout part; a discharging oil passage 48 for discharging the working oil passed through the first metering part; and a second metering part 50 arranged at the discharging oil passage.;SELECTED DRAWING: Figure 2;COPYRIGHT: (C)2016,JPO&INPIT