Regeleinrichtung für Verdrängerpumpen

摘要

The invention relates to a displacement pump, e.g. a vane cell pump, with a flow regulating valve (13) on the control piston (22) of which act the pump pressure on the one hand and the consumer pressure taken via a choke device on the other. The control piston (22) acts as a pressure scale in which the pressure difference as the pump speed rises acts as a measure of the adjusted quantity conveyed. The choke device for setting the pressure difference contains a choke piston (17) movable against the force of a spring (16) in a piston drilling (15), which closes off an aperture (14) on the pressure side in a control disc (7) in the basic position. According to the invention, the piston drilling (15) has a by-pass channel (18) which continuously connects the pump with a spring chamber (15A) in the choke piston (17). In addition, depending on the flow rate, the choke piston controls the cross-section of a choke channel (20) providing a connection between the spring chamber (15A) and the outlet channel (21). The arrangement has the advantage that the differential pressure of the control piston (22) cannot affect the choke piston (17) of the choke device. As the spring force acting on the choke piston (17) can be reduced, power is saved.