CN-115699533-B - Lubricant-supporting motor with multiple electrical conductors serving as an outer race

CN115699533BCN 115699533 BCN115699533 BCN 115699533BCN-115699533-B

Abstract

An electric motor includes a stator presenting a first surface. A rotor is rotatable relative to the stator. The rotor presents a rotor raceway disposed in spaced relation to the first surface of the stator. The first surface of the stator defines a plurality of slots in spaced relation to one another to define a plurality of spaced teeth therebetween. At least one electrical conductor is disposed in each of the plurality of slots and is configured to selectively generate a moving magnetic field to act on the rotor to provide rotational movement of the rotor. A portion of the at least one electrical conductor extends substantially in radial alignment with or beyond the first surface of the stator to at least partially define a stator race of the stator for engaging the rotor race of the rotor during relative radial movement between the rotor and the stator.

Inventors

Donald Lemborsky
Jacqueline Dedo
Mark vilsteyer

Assignees

尼亚布科知识产权控股有限责任公司

Dates

Publication Date: 20260512
Application Date: 20210608
Priority Date: 20200608

Claims (14)

1. An electric motor, characterized in that the electric motor comprises: an annular stator extending about an axis and presenting a first radial surface; A rotor extending about said axis and rotatable relative to said stator and presenting a second radial surface defining a rotor raceway disposed in spaced relation to said first radial surface of said stator to define a gap therebetween for containing a lubricant; The first radial surface of the stator defining a plurality of slots spaced apart from one another to define a plurality of spaced apart teeth between the plurality of slots; At least one electrical conductor disposed in each of the plurality of slots and configured to selectively generate a moving magnetic field to act on the rotor to provide rotational movement of the rotor in response to an electrical current applied to the at least one electrical conductor, and A portion of the at least one electrical conductor in each of the plurality of slots extending substantially in radial alignment with or beyond the first radial surface of the stator to at least partially define a stator race of the stator for engaging the rotor race of the rotor during relative movement between the rotor and the stator to act as a bearing while also generating the moving magnetic field; the at least one electrical conductor in each of the plurality of slots comprises a plurality of electrical conductors in each of the plurality of slots, and wherein the plurality of electrical conductors in each of the plurality of slots comprises at least a first electrical conductor radially stacked on a second electrical conductor, and wherein the first electrical conductor is made of a material that is harder and less conductive than the second electrical conductor.
2. The motor of claim 1 wherein said first electrical conductor is comprised of one of a copper iron and copper zinc material and wherein said second electrical conductor is comprised of one of an oxygen-loaded copper and an oxygen-free highly conductive copper.
3. The motor of claim 1 wherein said plurality of electrical conductors in each of said plurality of slots further comprises a third electrical conductor located radially below said second electrical conductor, and wherein said first electrical conductor is made of a harder and less conductive material than said third electrical conductor.
4. The motor of claim 1 wherein said first and second electrical conductors in each of said plurality of slots are assembled in said slots using at least one of an interference press fit, a heat shrink fit, and a displacement/deformation rolling process to provide a close fit of said first and second electrical conductors in said slots.
5. The motor of claim 1 wherein each of said first and second electrical conductors of each of said plurality of slots defines at least one substantially planar surface, and wherein said plurality of substantially planar surfaces of said first and second electrical conductors overlap and engage one another in said slots to provide mechanical rigidity and minimize insulation between said first and second electrical conductors.
6. The motor of claim 1 wherein said at least one electrical conductor in each of said plurality of slots is an axially extending conductive rod.
7. The motor of claim 1 wherein said at least one electrical conductor in each of said plurality of slots is comprised of a plurality of windings.
8. The motor of claim 1 wherein said at least one electrical conductor in each of said plurality of slots extends radially inward through said first radial surface of said stator.
9. The motor of claim 1 wherein said at least one electrical conductor in each of said plurality of slots extends into radial alignment with said first radial surface of said stator such that said stator race is defined by a plurality of circumferentially alternating segments of said plurality of electrical conductors and said first radial surface of said stator.
10. The motor of claim 1 wherein said stator track presents a substantially smooth surface in a circumferential direction.
11. The motor of claim 10 wherein a polymer coating extends over said at least one electrical conductor in each of said plurality of slots and said first radial surface of said stator to define said substantially smooth surface of said stator race.
12. The motor of claim 1 wherein said stator defines at least one passage in fluid communication with said gap for delivering a lubricant into said gap.
13. The motor of claim 1 wherein a bearing sleeve is not radially located in said gap between said stator and said rotor.
14. An electric motor, characterized in that the electric motor comprises: an annular stator extending about an axis and presenting a first radial surface; A rotor extending about said axis and rotatable relative to said stator and presenting a second radial surface defining a rotor raceway disposed in spaced relation to said first radial surface of said stator to define a gap therebetween for containing a lubricant; The first radial surface of the stator defining a plurality of slots spaced apart from one another to define a plurality of spaced apart teeth between the plurality of slots; At least one electrical conductor disposed in each of the plurality of slots and configured to selectively generate a moving magnetic field to act on the rotor to provide rotational movement of the rotor in response to an electrical current applied to the at least one electrical conductor, and A portion of the at least one electrical conductor in each of the plurality of slots extending substantially in radial alignment with or beyond the first radial surface of the stator to at least partially define a stator race of the stator for engaging the rotor race of the rotor during relative movement between the rotor and the stator to act as a bearing while also generating the moving magnetic field; The at least one electrical conductor in each of the plurality of slots comprises a plurality of electrical conductors in each of the plurality of slots, and wherein the plurality of electrical conductors in each of the plurality of slots comprises at least a first electrical conductor radially stacked on a second electrical conductor; Each of the first and second electrical conductors of each of the plurality of slots defines at least one substantially planar surface, and wherein the plurality of substantially planar surfaces of the first and second electrical conductors overlap and engage each other in the slots to provide mechanical rigidity and minimize insulation of the first and second electrical conductors.

Description

Lubricant-supporting motor with multiple electrical conductors serving as an outer race Cross-reference to related applications The present application claims priority to the provisional patent application of U.S. patent application No. 63/036,167, filed on 6/8 of 2020, the entire disclosure of which is incorporated herein by reference in its entirety. Technical Field The present disclosure relates generally to a lubricant supported motor. More particularly, the present disclosure relates to a lubricant support motor having a race of a stator defined by a plurality of electrical conductors. Background This section provides a general overview of background information, and the various comments and examples provided in this section are not necessarily prior art to the present disclosure. Various drivetrain in automotive, truck, and certain off-highway applications draw power from a central prime mover, such as an internal combustion engine ("internal combustion engine, ICE"), and distribute the power to a plurality of wheels using a plurality of mechanical devices, such as a plurality of transmissions, a plurality of propeller shafts, and a plurality of drive shafts. However, more and more attention is directed to alternative arrangements for prime movers that provide improved environmental performance, eliminate mechanical driveline components, and create lighter weight vehicles that provide more space for multiple passengers and payloads. An "on-wheel", "in-wheel" or "near-wheel" motor configuration is an alternative arrangement to a plurality of conventional ICE prime movers that distribute the prime mover functions to each or some of the plurality of wheels via one or more electric motors disposed on, within or near the plurality of wheels. For example, in one case, a traction motor that uses a central shaft through a rotor and rolling multiple element bearings to support the rotor may be used as the "on-wheel", "in-wheel" or "near-wheel" motor configuration. In another case, a lubricant supporting motor, such as described in U.S. application Ser. No. 16/144,002, may be used as the "on-wheel", "in-wheel" or "near-wheel" motor configuration. Although each of these electric motor configurations results in a smaller size and lighter weight arrangement than the multiple prime movers based on multiple ICEs, there is still room for further improvement. For example, using multiple traction motors as the "on-wheel", "in-wheel", or "near-wheel" configuration still results in multiple motors being relatively heavy and often insufficient to withstand impact loads, and not optimized for a variety of wheel end applications. In other words, the current plurality of traction motors are large and heavy structures supported by rolling multiple element bearings, which are relatively heavy for a variety of practical wheel end applications. In an automotive or land vehicle application, lubricant support motors as the "on-wheel," "in-wheel," or "near-wheel" motors are a lightweight alternative to traction motors. Such lubricant-supported motors include a lubricant disposed in a gap between a rotor and stator for supporting the rotor within the stator and providing continuous contact between these components. The lubricant may thus act as a bearing (e.g., suspension) between the rotor and stator, minimizing or preventing contact therebetween. It is known to provide a bearing housing of high resistivity material, such as Hastelloy or terling (Delrin), between the rotor and stator to accommodate rotational contact between the rotor and stator. One problem with such bearing sleeves is that they cause multiple eddy current losses (eddy current loss) of the stator, resulting in reduced performance. It is also known to provide a non-conductive polymer bearing sleeve between the rotor and stator, but such bearing sleeves have relatively poor mechanical properties. Furthermore, both options require additional manufacturing and assembly steps. Thus, while known lubricant support motors provide a lightweight alternative to traction motors, there is still a need for further improvements. Disclosure of Invention An electric motor includes a stator including a first surface. A rotor extends about an axis and is rotatable relative to the stator. The stator presents a rotor raceway disposed in spaced relation to the first surface of the stator to define a gap therebetween to contain a lubricant. The first surface of the stator defines a plurality of slots in spaced relation to one another to define a plurality of spaced teeth therebetween. At least one electrical conductor is disposed in each of the plurality of slots and configured to selectively generate a moving magnetic field to act on the rotor to provide rotational movement of the rotor in response to an electrical current applied to the at least one electrical conductor. A portion of the at least one electrical conductor in each of the plurality of slots extends substantially in radia