Taking the multi-way valve of a certain model hydraulic excavator shown in Figure 2.3 as the research object, the multi-way valve is divided into two valve blocks A and B, and the two valve blocks are connected by screws. A valve block includes: left travel valve, boom merge valve, P2 pump unloading valve, rotary valve, stick 1 valve and optional valve; B valve block includes: walking straight inlet valve, P1 pump unloading valve, right travel valve , Boom valve, bucket valve and stick 2 valve. The principle diagram of the multi-way valve hydraulic system is shown in Figure 2.4. The system is a dual pump dual circuit system.
Figure 2.3: On the A valve block, PAL / PBL is the forward / reverse pilot port of the left travel valve; AL / BL is the forward / backward port of the left travel valve: PB1 is the pilot port of the boom confluence valve: PCa is the P2 pump Pilot port for unloading valve: PAs / PBs for rotary valve right / left pilot port: As / Bs for rotary valve right / left port: PAal / PBal for stick 1 valve retract / release pilot port; Aal / Bal for The stick 1 valve retracts / releases the oil port; PAo / PBo is the option valve pilot port; Ao / Bo is the option valve port.
On the B valve block, PTb is the pilot oil port of the walking straight inlet valve: PCb is the pilot oil port of the P1 pump unloading valve: PAr / PBr is the forward / reverse pilot oil port of the right travel valve: Ar / Br is the forward / backward oil of the right travel valve Port: PAb / PBb is the boom valve lowering / lifting pilot port: Ab / Bb is the boom valve lowering / lifting port; PAc / PBc is the bucket valve digging / unloading pilot port; Ac / Bc is the bucket Valve digging / unloading port; PAa2 / PBa2 is the stick 2 valve retract / release pilot port; Aa2 / Ba2 is the stick 2 valve retract / release port.
