Hydraulic pumping device`s e.g. vane pump, pressuring medium flow controlling device for e.g. passenger car, has discharge valve for pressurizing medium controlled, so that constant medium pressure is made possible in supply line for load

摘要

The device has a valve chamber (5) separated from another valve chamber (9) by a control piston, where the chamber (5) is in fluid connection with a supply line for a load by a control line upstream of an orifice. The chamber (9) is connected with a discharge valve (12) designed as 2/2-way valve for a pressurizing medium. The valve (12) is controlled based on parameters of surrounding areas of the device, such that constant medium pressure lower than an operating pressure for the load is made possible in the supply line, when the valve (12) is in an opened state. The piston is adjusted in dependence of the pressure difference at the orifice in the line to discharge a part of the pressurizing medium from the line (8) and to keep constant the flow rate of the medium to the load.