Integrated endshield and pump volute for an electric pump and method of forming an electric pump
View Patent ↗An electric pump has a stator, a rotor, a pump volute, and an endshield. The pump volute and the endshield are formed together as a single monolithic part, thereby minimizing the axial length of the electric pump. A drainage passageway is provided on the endshield to harmlessly drain away any fluid that seeps past the pump's seals. In one embodiment of the invention, the drainage passageway is a groove that faces the stator and is configured to facilitate the evaporation of and leak fluid by channeling the fluid near the stator, which warms the fluid and thereby increases the fluid's evaporation rate.
1. An improved electric pump comprising a stator, a rotor, an endshield, and a bearing, the rotor having a rotor shaft, the endshield being fixed to the stator and comprising a shaft opening, the shaft opening extending through the endshield, the rotor shaft extending through the shaft opening, the bearing being supported by the endshield, the bearing at least partially supporting the rotor shaft in a manner allowing the rotor shaft to revolve relative to the endshield, the improvement comprising:
a spiral formation, the spiral formation constituting at least a portion of a fluid pump volute, the spiral formation and the endshield being monolithically formed together as a single part;
a drainage passageway formed in the endshield, the drainage passageway extending downward from the shaft opening and being configured and adapted to channel liquid downward from the shaft opening via gravity; and
a fluid reservoir formed by the endshield, the drainage passageway operatively connecting the shaft opening to the fluid reservoir, the fluid reservoir being exposed to and spaced from a surface of the stator.
2. An electric pump in accordance with claim 1 wherein the fluid reservoir comprises a recess in a generally horizontal surface of the endshield that is beneath the stator.
3. An electric pump comprising:
a stator, the stator having a surface;
a rotor, the rotor having a rotor shaft;
an endshield, the endshield being fixed to the stator and comprising a shaft opening and a spiral formation, the shaft opening extending through the endshield, the rotor shaft extending through the shaft opening, the spiral formation constituting at least a portion of a fluid pump volute, the spiral formation and the endshield being monolithically formed together as a single part, the endshield also comprising a drainage passageway and a fluid reservoir, the drainage passageway operatively connecting the shaft opening to the fluid reservoir, the fluid reservoir being exposed to and spaced from the surface of the stator, the drainage passageway extends downward from the shaft opening and is configured and adapted to channel liquid downward from the shaft opening via gravity;
a bearing, the bearing being supported by the endshield, the bearing at least partially supporting the rotor shaft in a manner allowing the rotor shaft to revolve relative to the endshield.
4. An electric pump in accordance with claim 3 wherein the fluid reservoir comprises a recess in a generally horizontal surface of the endshield that is beneath the stator.
5. An electric pump comprising
a stator;
a rotor, the rotor having a rotor shaft;
an endshield, the endshield being fixed to the stator and comprising a shaft opening, a spiral formation, and a drainage groove, the shaft opening extending through the endshield, the spiral formation constituting at least a portion of a fluid pump volute, the rotor shaft extending through the shaft opening, the drainage groove extending downward from the shaft opening and being configured and adapted to channel liquid downward from the shaft opening via gravity, the drainage groove facing the stator, the spiral formation and the drainage groove being on opposite sides of the endshield, the spiral formation and the endshield being monolithically formed together as a single part, the endshield further comprising a fluid reservoir, the drainage groove operatively connecting the shaft opening to the fluid reservoir, the fluid reservoir being exposed to and spaced from the surface of the stator; and
a bearing, the bearing being supported by the endshield, the bearing at least partially supporting the rotor shaft in a manner allowing the rotor shaft to revolve relative to the endshield.
6. An electric pump in accordance with claim 5 wherein the fluid reservoir comprises a recess in a generally horizontal surface of the endshield that is beneath the stator.
7. A method of forming an electric motor, the method comprising:
molding an endshield in a manner such that the endshield comprises a spiral formation, a shaft opening, a drainage passageway, and a fluid reservoir, the shaft opening extending through the endshield, the spiral formation constituting at least a portion of a fluid pump volute, the spiral formation and the endshield being monolithically formed together as a single part, the drainage passageway extends downward from the shaft opening and being configured and adapted to channel liquid downward from the shaft opening via gravity, the drainage passageway operatively connecting the shaft opening to the fluid reservoir;
attaching the endshield to a stator having a surface in a manner such that the spiral formation faces away from the stator and the fluid reservoir is exposed to and spaced from the surface of the stator;
positioning a bearing in the shaft opening of the endshield;
positioning a rotor shaft in manner such that the rotor shaft extends through the bearing and through the shaft opening of the endshield.