Canned rotor pump for heating systems - has automatic valve controlling flow of lubricating water to prevent loss during venting

摘要

The pump has an impeller (3) on the end of a shaft (10). The shaft carries the rotor (7) of an electric motor which is separated from the stator (6) by a thin can (8). A bore (11) through the shaft takes water to a space (13) at the end of the motor from which it can flow to lubricate the bearings (23). The space at the end of the motor is closed by a nut (14) which can be removed for inspection and cleaning. A valve (15,16,17) in the end of the hollow shaft is opened by the differential pressure between the pump suction (4) and the space (13) at the motor end.