US Patent 10253789 Hydraulic arrangement for a lifting unit

A hydraulic arrangement for lifting and/or lowering at least one implement carrying arm on an agricultural machine. The arrangement comprises an inlet hydraulic line and an outlet hydraulic line connecting a fluid pump and a fluid reservoir respectively to a first valve means, said arrangement comprising at least one dual acting hydraulic cylinder for lifting/and or lowering the implement carrying arm. The at least one cylinder is connected to the first valve means allowing the cylinder to be switched between a single acting mode wherein the arm can be lifted and a double acting mode wherein the arm can be lifted and lowered.