If the principle of the closed circuit is applied to a differential cylinder, the fact that different areas are involved means suction must also take place from the container when switching to feed mode, while during reflux most excess oil must flow away via a throttling point (4) (Figure H 4).
![c85b00c96087d46d6f430580e1c8f6ffb8c8b511 0001_halboffenerkreislauf_halbgeschlossenerk__.gif](/fileadmin/smc/files/c85b00c96087d46d6f430580e1c8f6ffb8c8b511.gif)
Figure H 4: Half open hydraulic circuit