Figure 5.36. Hydraulic fluid flow during mast lifting
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1.
The operator moves the lifting/lowering control to the lifting position. The motor starts the pump and the pump draws hydraulic fluid from the tank.
2.
The hydraulic fluid flows to the relief valve and through the check valve to the proportional valve (M1) and back to the tank.
3.
The proportional valve (M1) is fully open. Then the valve is slightly closed and the pressure increases. This allows stepless control of lifting with loaded forks.
4.
The pressurised hydraulic fluid opens the next check valve in M2 and flows to the mast main lift cylinder.
