Abstract: A method of forming a balancing scallop within a rotating part, including inspecting the rotating part for imbalance, calculating dimensions of the balancing scallop to be formed within the rotating part, positioning the rotating part relative to a material removal machine, starting the tool removal machine, bringing the rotating part and a tool of the material removal machine into engagement, forming a first section of the balancing scallop, forming a second section of the balancing scallop, forming a third section of the balancing scallop, and dis-engaging the rotating part and the tool of the material removal machine.

Abstract: An electric machine includes a stator with stator slots securing therein electrically conductive windings. A rotor is rotatably mounted adjacent the stator and includes a stack of rotor laminates. Each laminate includes circumferentially spaced poles, each of which includes a magnet slot spaced from an insert slot. These laminate magnet slots cooperatively define the rotor's magnet slots. Likewise, the laminates' insert slots cooperatively define the rotor's insert slots. Magnets are mounted inside the rotor's magnet slots, and non-magnetic inserts are mounted inside the rotor's insert slots. One or more poles of each laminate includes a structural web that extends radially through the magnet and insert slots of that pole. Multiple poles of each rotor laminate lack a radially extending structural web. Each rotor laminate is rotated with respect to a neighboring rotor laminate such that each pole with a structural web axially aligns with a pole without a structural web.

Abstract: An adhesive-reinforced rotor for a rotary electric machine includes rotor lamination layers (“rotor lams”) having axial inner surfaces collectively defining rotor openings through the rotor lams. The rotor also includes reinforcement blocks disposed within a respective one of the rotor openings. A polymer primer/adhesive layer of the rotor having a bond line thickness of less than 1 mm is disposed between the one or more reinforcement blocks and the axial inner surfaces of the rotor lams. The reinforcement blocks and the primer/adhesive layer each have a tensile strength of at least 50 MPa. A modulus of elasticity of the reinforcement blocks is at least three times greater than that of the materials of the polymer primer/adhesive layer. A method of constructing an adhesive-reinforced rotor is also described herein.

Abstract: An electric motor assembly includes a housing having a generally cylindrical inner surface defining a generally cylindrical cavity within the housing, a stator operatively disposed within the generally cylindrical cavity, the stator including a plurality of stacked laminations wherein each lamination has an outer circumferential edge and a plurality of finger elements extending inward, and a layer of polymer disposed between a generally cylindrical outer surface of the stator and the generally cylindrical inner surface of the housing, such that the stator is fastened to the housing by the polymer. A method of manufacturing the electric motor assembly includes disposing a stator within a housing such that a gap is defined between the stator and the housing and the stator is not directly connected to the housing, and substantially filling the gap with a polymer capable of fastening the stator to the housing by only the polymer.

Abstract: An induction motor includes a stator and a rotor. The stator is configured to generate a rotating magnetic field. The rotor is disposed inside the stator, separated from the stator by an air gap, and is configured to rotate around an axis in response to the rotating magnetic field. The rotor includes a rotor core, multiple end rings, and multiple collars. The end rings are attached at opposite ends of the rotor core. Each end ring has one of multiple regions disposed outside the air gap. Each region has an outer surface. The collars are attached in a prestressed condition around the outer surface of each region. The prestressed condition is configured to maintain a compressive stress in the end rings at a maximum-designed rotational speed of the rotor.

Abstract: An electric machine may include a rotor having a notch at each pole wherein each notch is skewed by some mechanical angle. Notches may fluidly couple one end of the rotor to the other end of the rotor and provide pumping functionality for fluid therein.

Abstract: An electric machine may include a substantially annular stator stack having a plurality of laminations which include mounting ears. A fraction of the laminations may be oriented such that the mounting ears are angularly offset from the others. The stator may be secured to a housing at both mounting ear locations thus improving structural rigidity and enhancing performance.

Abstract: An induction motor includes a stator and a rotor. The stator is configured to generate a rotating magnetic field. The rotor is disposed inside the stator, separated from the stator by an air gap, and is configured to rotate around an axis in response to the rotating magnetic field. The rotor includes a rotor core, multiple end rings, and multiple collars. The end rings are attached at opposite ends of the rotor core. Each end ring has one of multiple regions disposed outside the air gap. Each region has an outer surface. The collars are attached in a prestressed condition around the outer surface of each region. The prestressed condition is configured to maintain a compressive stress in the end rings at a maximum-designed rotational speed of the rotor.

Abstract: An adhesive-reinforced rotor for a rotary electric machine includes rotor lamination layers (“rotor lams”) having axial inner surfaces collectively defining rotor openings through the rotor lams. The rotor also includes reinforcement blocks disposed within a respective one of the rotor openings. A polymer primer/adhesive layer of the rotor having a bond line thickness of less than 1 mm is disposed between the one or more reinforcement blocks and the axial inner surfaces of the rotor lams. The reinforcement blocks and the primer/adhesive layer each have a tensile strength of at least 50 MPa. A modulus of elasticity of the reinforcement blocks is at least three times greater than that of the materials of the polymer primer/adhesive layer. A method of constructing an adhesive-reinforced rotor is also described herein.

Abstract: An electric machine includes a stator with stator slots securing therein electrically conductive windings. A rotor is rotatably mounted adjacent the stator and includes a stack of rotor laminates. Each laminate includes circumferentially spaced poles, each of which includes a magnet slot spaced from an insert slot. These laminate magnet slots cooperatively define the rotor's magnet slots. Likewise, the laminates' insert slots cooperatively define the rotor's insert slots. Magnets are mounted inside the rotor's magnet slots, and non-magnetic inserts are mounted inside the rotor's insert slots. One or more poles of each laminate includes a structural web that extends radially through the magnet and insert slots of that pole. Multiple poles of each rotor laminate lack a radially extending structural web. Each rotor laminate is rotated with respect to a neighboring rotor laminate such that each pole with a structural web axially aligns with a pole without a structural web.

Abstract: An electric motor assembly includes a housing having a generally cylindrical inner surface defining a generally cylindrical cavity within the housing, a stator operatively disposed within the generally cylindrical cavity, the stator including a plurality of stacked laminations wherein each lamination has an outer circumferential edge and a plurality of finger elements extending inward, and a layer of polymer disposed between a generally cylindrical outer surface of the stator and the generally cylindrical inner surface of the housing, such that the stator is fastened to the housing by the polymer. A method of manufacturing the electric motor assembly includes disposing a stator within a housing such that a gap is defined between the stator and the housing and the stator is not directly connected to the housing, and substantially filling the gap with a polymer capable of fastening the stator to the housing by only the polymer.

Abstract: A method of forming a balancing scallop within a rotating part, including inspecting the rotating part for imbalance, calculating dimensions of the balancing scallop to be formed within the rotating part, positioning the rotating part relative to a material removal machine, starting the tool removal machine, bringing the rotating part and a tool of the material removal machine into engagement, forming a first section of the balancing scallop, forming a second section of the balancing scallop, forming a third section of the balancing scallop, and dis-engaging the rotating part and the tool of the material removal machine.

Abstract: An electric machine may include a substantially annular stator stack having a plurality of laminations which include mounting ears. A fraction of the laminations may be oriented such that the mounting ears are angularly offset from the others. The stator may be secured to a housing at both mounting ear locations thus improving structural rigidity and enhancing performance.

Abstract: A motor stator includes a plurality of stacked annular stator laminates defining a stator core having a plurality of stator teeth on an inner diameter thereof, at least some of the plurality of stator laminates including a plurality of coolant openings therethrough. The plurality of coolant openings of adjacent stator laminates communicate with one another in order to define cooling channels inside the stator core. At least some of the plurality of stator laminates include the plurality of coolant openings including a plurality of generally circumferentially extending slots.

Abstract: A rotor for an electric machine comprises a rotor core that defines a rotor slot having a central portion and an end portion. The end portion has a maximum width that is greater than a maximum width of the central portion immediately adjacent the end portion. A perimeter of the rotor slot at the end portion includes a plurality of segments extending between a first extremity at the maximum width of the end portion and a second extremity at the maximum width of the end portion. The plurality of segments include segments with different radii that decrease in magnitude from the center axis to the first extremity, and from the center axis to the second extremity.

Abstract: A motor stator includes a plurality of stacked annular stator laminates defining a stator core having a plurality of stator teeth on an inner diameter thereof, at least some of the plurality of stator laminates including a plurality of coolant openings therethrough. The plurality of coolant openings of adjacent stator laminates communicate with one another in order to define cooling channels inside the stator core. At least some of the plurality of stator laminates include the plurality of coolant openings including a plurality of generally circumferentially extending slots.

Abstract: A rotor for an electric machine comprises a rotor core that defines a rotor slot having a central portion and an end portion. The end portion has a maximum width that is greater than a maximum width of the central portion immediately adjacent the end portion. A perimeter of the rotor slot at the end portion includes a plurality of segments extending between a first extremity at the maximum width of the end portion and a second extremity at the maximum width of the end portion. The plurality of segments include segments with different radii that decrease in magnitude from the center axis to the first extremity, and from the center axis to the second extremity.