US Patent 9624945 Circulation pump

An electric pump has a pump casing, a sealing plate, an impeller and a motor for driving the impeller. The pump casing has a main body. A recess is formed in the main body and with the sealing plate defines a pump chamber. A suction port is connected to the pump chamber by a suction channel and a suction passage formed in the main body. A discharge port is connected to the pump chamber by a discharge channel. The suction passage extends axially from the recess. The recess, suction passage, suction channel and discharge channel are all shaped in a manner allowing the pump casing can be molded as a monolithic structure in a single injection molding process.