Electric motor for use in pressurized fluid environment
An electric motor built for exposure to high pressure fluid includes a unitary metal sleeve that provides a fluid barrier between the rotor and the stator. An overmolded resin encapsulates the stator windings and reinforces the sleeve to minimize deformation of the sleeve under high fluid pressures. The overmolded resin also fixes the positions of insulation displacement connectors connected to the stator windings, thereby avoiding mechanical brackets and fasteners for holding the insulation displacement connectors in position.
1. An electric motor comprising:
a rotor having an axis of rotation;
a stator surrounding the rotor, the stator including a plurality of windings;
a unitary metal sleeve including a side portion between the rotor and the stator and a flange portion extending radially outward from the side portion, wherein the unitary metal sleeve provides a fluid barrier between the rotor and the stator; and
a resin overmold encapsulating the stator, wherein the resin overmold engages the side portion of the unitary metal sleeve and the flange portion of the unitary metal sleeve;
a unitary metal housing including at least one sidewall defining a cylindrical cavity aligned along the axis of rotation of the rotor and an end wall adjacent the at least one side wall, wherein the rotor and the stator are received within the cylindrical cavity of the unitary metal housing;
wherein the end wall of the unitary metal housing includes a recess, and the unitary metal sleeve further includes a closed end portion projecting into the recess in the end wall of the unitary metal housing; and
wherein the end portion of the unitary metal sleeve and the recess in the end wall of the unitary metal housing correspond in shape and are in surface-to-surface engagement with one another.
2. The electric motor according to claim 1 , wherein the end wall of the unitary metal housing has a plurality of portals extending through the end wall and communicating with the cylindrical cavity.
3. The electric motor according to claim 1 , wherein the end portion of the sleeve and the recess in the end wall each include a frusto-conical in shape.
4. The electric motor according to claim 1 , wherein the side portion of the unitary metal sleeve includes a radially reduced portion tapering in a direction away from the flange portion.
5. The electric motor according to claim 4 , wherein the resin overmold engages the radially reduced portion of the side portion of the unitary metal sleeve.
6. The electric motor according to claim 1 , wherein the housing is a die cast housing.
7. The electric motor according to claim 1 , wherein flange portion includes a rim having an axially extending portion.