# US 12,184,123 B2 · Three-dimensional airgap electric machines employing winding embedded liquid cooling > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,184,123 B2 - Document ID: US12184123B2 - Status: Granted - Kind: B2 - Application number: 17/482,645 - Filed: 2021-09-23 - Published: 2022-03-24 - Granted: 2024-12-31 - Earliest claimed: 2020-09-24 - Assignees: North Carolina State University Office of Research Commercialization - Applicants: North Carolina State University - Inventors: Md Sariful Islam; Iqbal Husain; Ritvik Chattopadhyay; Gregory D. Buckner - Web page: https://patentgrep.com/patent/US12184123B2 ## CPC - H02K 1/20: with channels or ducts for flow of cooling medium - H02K 16/02: Machines with one stator and two {or more} rotors - H02K 1/16: Stator cores with slots for windings - H02K 1/17: Stator cores with permanent magnets - H02K 1/2792: with magnets arranged in Halbach arrays - H02K 1/2795: the rotor consisting of two or more circumferentially positioned magnets - H02K 1/32: with channels or ducts for flow of cooling medium - H02K 1/325: {between salient poles} - H02K 7/14: Structural association with mechanical loads, e.g. with hand-held machine tools or fans (with fan or impeller for cooling the machine H02K9/06) - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - H02K 16/04: Machines with one rotor and two stators - H02K 21/24: with magnets axially facing the armatures, e.g. hub-type cycle dynamos - H02K 2201/03: Machines characterised by aspects of the air-gap between rotor and stator - H02K 2213/03: Machines characterised by numerical values, ranges, mathematical expressions or similar information - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract Various examples are provided related to 3D airgap electric machines and winding embedded liquid cooling. In one example, an electric machine includes a stator assembly with stator windings supported by a stator core and an outer rotor assembly includes a radial plate surrounding the stator assembly and an endplate at a first end of the radial plate adjacent to the first end of the stator core. The stator windings can include a first portion extending along an axial length of the stator core and a second portion at a first end of the stator core that extends radially inward towards a shaft of the electric machine. The radial plate can include magnets distributed about the radial plate. In another example, a stator assembly includes stator windings supported by a stator core with a winding support including cooling channels distributed between the stator windings. The winding support can be nonmagnetic. ## Claims ### Claim 1 An electric machine, comprising: a stator assembly comprising a plurality of stator windings supported by a stator core, each of the plurality of stator windings comprising a first portion extending along an axial length of the stator core and a second portion at a first end of the stator core that extends radially inward towards a shaft of the electric machine, where the first portion is held along the axial length by a winding support of the stator core, the winding support including a cooling channel extending axially through the winding support and the first portion of the supported stator winding; and an outer rotor assembly comprising a radial plate surrounding the stator assembly and an endplate at a first end of the radial plate adjacent to the first end of the stator core, the radial plate comprising a plurality of magnets distributed about the radial plate. ### Claim 2 (depends on 1) The electric machine of claim 1, wherein the second portion of each stator winding extends radially inward in a triangular or trapezoid fashion with a narrower side adjacent to the shaft of the electric machine. ### Claim 3 (depends on 1) The electric machine of claim 1, wherein the endplate comprises a plurality of endplate magnets distributed about the shaft of the electric machine, the plurality of endplate magnets adjacent to the second portion of the plurality of stator core windings. ### Claim 4 (depends on 3) The electric machine of claim 3, wherein the plurality of endplate magnets are distributed in a Halbach magnetization pattern. ### Claim 5 (depends on 1) The electric machine of claim 1, wherein the winding support extends along the second portion of the supported stator winding. ### Claim 6 (depends on 5) The electric machine of claim 5, wherein cooling channels extend axially through the winding support and radially inward toward a center axis of the stator core through the winding support. ### Claim 7 (depends on 5) The electric machine of claim 5, wherein the stator core comprises a stator yoke positioned within and supporting the winding support, the stator yoke comprising yoke cooling channels extending through and distributed around the stator yoke. ### Claim 8 (depends on 7) The electric machine of claim 7, wherein the yoke channels are within an aluminum sleeve. ### Claim 9 (depends on 1) The electric machine of claim 1, wherein the first portion of the stator winding is excited by a first inverter and the second portion of the stator winding is excited by a second invertor. ### Claim 10 (depends on 9) The electric machine of claim 9, wherein the stator core comprises the winding support comprising cooling channels distributed between the plurality of stator windings and the winding support is nonmagnetic. ### Claim 11 (depends on 1) The electric machine of claim 1, wherein the winding support is thermally conductive. ### Claim 12 (depends on 11) The electric machine of claim 11, wherein the winding support comprises a plastic material. ### Claim 13 (depends on 7) The electric machine of claim 7, wherein the cooling channel and yoke cooling channels provide parallel cooling paths of the stator assembly. ### Claim 14 (depends on 7) The electric machine of claim 7, wherein the cooling channel and yoke cooling channels provide series cooling paths of the stator assembly. ### Claim 15 (depends on 1) The electric machine of claim 1, wherein the cooling channel is a liquid cooling channel.