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 ( 10 ) comprising:
a rotor ( 12 ) having an axis of rotation ( 13 );
a stator ( 14 ) surrounding the rotor, the stator including a plurality of windings ( 22 );
a unitary metal sleeve ( 24 ) including a side portion ( 24 A) between the rotor and the stator and a flange portion ( 24 C) extending radially outward from the side portion, wherein the unitary metal sleeve provides a fluid barrier between the rotor and the stator, wherein the flange portion includes a rim ( 27 ) having an axially extending portion ( 27 A); and
a resin overmold ( 28 ) encapsulating the stator, wherein the resin overmold engages the side portion of the unitary metal sleeve;
a unitary metal housing ( 16 ) including at least one sidewall ( 16 A) defining a cavity ( 20 ) extending along the axis of rotation of the rotor and an end wall ( 16 B) adjacent the at least one side wall, wherein the rotor and the stator are received within the cavity of the unitary metal housing;
wherein the end wall of the unitary metal housing includes a recess ( 17 ), and the unitary metal sleeve further includes a closed end portion ( 24 B) 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 axially extending portion of the rim is radially spaced from an inner surface of the at least one sidewall of the unitary metal housing.
3. The electric motor according to claim 2 , wherein the cavity and the axially extending portion of the rim are each cylindrical, and an annular space is defined between the axially extending portion of the rim and the inner surface of the at least one sidewall.
4. The electric motor according to claim 1 , wherein the resin overmold further engages the flange portion of the unitary metal sleeve.