For the uniform lifting and lowering of pallet changers in laser cutting systems, it is crucial that all hydraulic cylinders move perfectly synchronously. The new decentralised solution LiftAx from HAWE Hydraulik realises synchronous movement with maximum precision and also offers advantages during installation and commissioning.
The plug & play unit consisting of hydraulic cylinder and hydraulic power pack type LiftAx is mounted at each lifting point of the pallet changer. With an external dimension of 415 x 338.5 mm, it is very compact and requires little installation space. A separate piping of the individual lifting units among each other is completely omitted. Due to the ready-to-connect delivery, installation and commissioning take place very quickly. In case of service, a unit can be replaced or repaired separately without having to dismantle the entire lifting table.
In addition, the low oil consumption of 0.7 liters per hydraulic power pack is convincing. In comparison, very specifically: With the use of 4 LiftAx modules in a pallet changer, only a total volume of about 3 applications of oil would be required. The classic solution with a standard hydraulic unit and central synchronization control block would usually require between 20 and 50 liters of oil, depending on the cylinder size.
The structure and functional principle of the LiftAx are convincingly simple:
Each hydraulic power pack consists of a tank with 1.75 kW motor and external gear pump. The required system pressure is set at a pressure-limiting valve. By means of a flow control valve and intelligent switching, it is ensured that the preset flow volume is exactly adhered to both when extending and retracting the cylinders. The leakage-free directional seated valve ensures that the cylinder position is securely maintained.
The HAWE flow control valve used in the LiftAx works load-independent and with an extraordinarily high precision compared to others in the market. Tests showed a tolerance of less than +/- 5 percent. This ensures very good synchronization of the lifting cylinder movements. The described high-precision flow control valve can also be ordered from the HAWE modular system for other applications.