Electric pump unit

Abstract

An electric pump unit that may be compactified and that may be reduced in weight and cost is provided. An electric pump unit is configured such that a pump chamber having an oil suction port and an oil discharge port is formed on an inner side of a motor stator that is fixedly provided on an inner periphery of a synthetic resin unit housing and only part of an inner peripheral side of which is exposed to an inside of the unit housing, a pump outer rotor is arranged on an inner side of the motor stator in the pump chamber so as to be able to rotate using an inner periphery of the motor stator as a guide, a pump inner rotor that is supported for rotation by the unit housing is arranged on an inner side of the pump outer rotor, and a motor rotor is formed such that a permanent magnet is held by a synthetic resin permanent magnet holding portion that is provided by integral molding on an outer periphery of the pump outer rotor.

1 . An electric pump unit comprising:
 a unit housing made of synthetic resin;   a motor stator that is fixed to an inner periphery of the unit housing in a state where part of an inner peripheral side of the motor stator is exposed; and   a pump chamber that is formed on an inner side of the motor stator and that has a fluid suction port and a fluid discharge port, wherein   a pump outer rotor that is able to rotate using an inner periphery of the motor stator as a guide and a pump inner rotor that is supported for rotation by the unit housing are arranged in the pump chamber,   a permanent magnet holding portion made of synthetic resin is integrally molded on an outer periphery of the pump outer rotor, and   a motor rotor is formed such that a permanent magnet is held by the permanent magnet holding portion.   
     
     
         2 . The electric pump unit according to  claim 1 , wherein a back yoke made of an iron-based material is in-molded in the pump outer rotor.