The hydraulic oil of the pump P1 flows into the housing A through the oilway inlet (P1), the central bypass oil passage 2, and the Unicom Oilway 3. The hydraulic oil of the pump P2 flows into the housing B through the oilway inlet (P2), the central bypass oil passage 2, and the Unicom Oilway 3.
The hydraulic oil of the pump PL flows directly into the fuel tank through the central bypass oil passage, negative control oil hole (NR1), the oil supply passage and the oil port (R2). The hydraulic oil of the pump P2 is also flowed into the fuel tank through the central bypass oil passage, negative control oil hole (NR2), the oil supply channel, and the oil port (R2). The hydraulic oil blocking the passage 3 and the passage 10 cannot be returned to the fuel tank.
If the control lever is operated, the hydraulic oil of the pump P2 is supplied from the channel to the walk right and supplied from the channel to the following spool: select, the arms 1, the bucket and the arm 2. Moreover, when the oil is supplied to the rotation, the large arm 2 and the appendicular, the hydraulic oil of the pump P1 is supplied from the channel to the travel left-axis core.
