Pump with piston movable in toroidal chamber - has cam track on impeller shaft to displace valve plate and allow passage of piston

摘要

The volumetric pump has a stator which contains a toroidal chamber. A rotor comprises an impeller with a rotating piston (19) guided in the chamber (5). A cam plate on the other side of the rotor has a circular cam track that controls a valve plate which can be withdrawn in order to allow the rotating piston to pass. The impeller (17) and the cam plate are positioned on a common shaft. The chamber is connected to inlet and outlet ports on either side of the valve plate.