Abstract: A device for controlling the quantity of hydraulic fluid returned to a pump from a double-acting lifting cylinder for lifting and lowering a load which moves through a dead point includes a housing, a control piston slidable within the housing and defining two spaces within the housing, each of the spaces being adapted to be connected to a pump. Two further spaces are provided within the housing and adapted to be connected, one to each side of the double-acting lifting cylinder. Each further space is connected with one of the spaces by way of a valve, and each of the valves is operable by means of the control piston. During use, the quantity of hydraulic fluid allowed to return from the lifting cylinder, through one of the further spaces and its associated valve and space, and returned to the pump, is proportional to the displacement of the control piston which depends on the pressure exerted by the pump.