D 8.602 Hydro-pneumatic pump units

Application
The hydro-pneumatic pump unit is particularly suitable for smaller hydraulic clamping and assembly fixtures with single or double-acting hydraulic elements.

Description
Single-acting version
The hydro-pneumatic pump unit is manually operated. Only by operating the pedal the fixture will be clamped or unclamped. The pump delivers oil as long as the desired operating pressure is obtained. Air pressure is adjusted by a pneumatic service unit. Oil pressure is maintained by an integrated check valve. The pump does not automatically supply oil in case of leaks!

Double-acting version
By pushing the pedal, the connected double-acting hydraulic cylinders are extended or retracted according to the position of the manual 4/3 directional control valve. The pedal has to be pushed as long as the cylinders are in its final position and the desired oil pressure is obtained. After release of the pedal, the pump does not re-deliver in case of pressure drop on the oil side! The pedal can be locked by the laterally-arranged pin with the description “PUSH INTO LOCK”, thereby the pump is continuously supplied with air. In this case the cylinders are exclusively activated by the 4/3 directional manual control valve. Small leaks are compensated by the pump and the oil pressure is maintained constantly.