# US 11,309,749 B2 · Stator assembly with teeth having different cross-sectional profiles with stem and head portions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,309,749 B2 - Document ID: US11309749B2 - Status: Granted - Kind: B2 - Application number: 16/542,337 - Filed: 2019-08-16 - Published: 2020-03-05 - Granted: 2022-04-19 - Earliest claimed: 2018-08-30 - Assignees: Etel S.A. - Applicants: Etel S.A. - Inventors: Manish Mittal; Johann Pourchet - Web page: https://patentgrep.com/patent/US11309749B2 ## CPC - H02K 1/146: {consisting of a generally annular yoke with salient poles} - H02K 1/276: Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] - H02K 21/16: having annular armature cores with salient poles (with homopolar co-operation H02K21/20) - H02K 29/03: with a magnetic circuit specially adapted for avoiding torque ripples or self-starting problems - 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 A stator assembly includes a stator having a plurality of teeth which are distributed around a circumference of the stator and point toward a central axis of the stator. The teeth alternately have a first cross-sectional profile and a second cross-sectional profile, and a plurality of slots being formed between the teeth. A plurality of coils are disposed around the teeth having the first cross-sectional profile. The second cross-sectional profile has a parallel-sided stem portion and an adjoining tapered head portion. A height of the stem portion of the second cross-sectional profile is less than a height of a respective one of the coils that is disposed around an adjacent one of the teeth having the first cross-sectional profile. ## Claims ### Claim 1 A stator assembly comprising: a stator having a plurality of teeth which are distributed around a circumference of the stator and point toward a central axis of the stator, the teeth alternately having a first cross-sectional profile and a second cross-sectional profile, a plurality of slots being formed between the teeth; and a plurality of coils which are disposed around the teeth having the first cross-sectional profile; wherein the second cross-sectional profile has a parallel-sided stem portion and an adjoining tapered head portion, and wherein a height of the stem portion of the second cross-sectional profile is less than a height of a respective one of the coils that is disposed around an adjacent one of the teeth having the first cross-sectional profile, wherein the head portion of the second cross-sectional profile is tapered in such a way that a smallest width of the head portion is in a range from 80% to 95% of a width of the stem portion of the second cross-sectional profile, and wherein the first cross-sectional profile has a parallel-sided portion along the height of the respective one of the coils, and wherein the teeth are arranged and the head portion of the second cross-sectional profile is tapered in such a way that an outer surface of the head portion of the second cross-sectional profile is oriented parallel to an outer surface of the parallel-sided portion of the respective one of the teeth having the first cross-sectional profile that is adjacent to a same respective one of the slots. ### Claim 2 (depends on 1) The stator assembly as recited in claim 1, wherein the height of the stem portion of the second cross-sectional profile is in a range of from 50% to 95% of an overall height of the second cross-sectional profile. ### Claim 3 (depends on 1) The stator assembly as recited in claim 1, wherein each of the coils has a circumferential surface that is parallel to an outer surface of the parallel-sided portion of the first cross-sectional profile around which the coil is disposed. ### Claim 4 (depends on 1) The stator assembly as recited in claim 1, wherein the first cross-sectional profile and the second cross-sectional profile have the same overall height. ### Claim 5 (depends on 1) The stator assembly as recited in claim 1, wherein a thickness of the coil is in a range of from 85% to 100% of a smallest distance between adjacent ones of the teeth. ### Claim 6 (depends on 1) The stator assembly as recited in claim 1, wherein the coils each have the same height, and each of the coils is disposed around a respective one of the teeth having the first cross-sectional profile. ### Claim 7 (depends on 1) The stator assembly as recited in claim 1, wherein the stator includes a stack of stator laminations, each having teeth which are distributed around a circumference of the stator lamination and point toward a central axis of the stator lamination and which alternately have the first and the second cross-sectional profile, a plurality of slots being formed between the teeth of the stator laminations. ### Claim 8 (depends on 1) The stator assembly as recited in claim 1, wherein an overall height of the first cross-sectional profile and an overall height of the second cross-sectional profiles are greater than the height of the respective one of the coils. ### Claim 9 (depends on 8) The stator assembly as recited in claim 8, wherein the first cross-sectional profile has a tapered head portion in a region extending beyond the respective one of the coils. ### Claim 10 A rotary synchronous motor comprising: a stator assembly comprising: a stator having a plurality of teeth which are distributed around a circumference of the stator and point toward a central axis of the stator, the teeth alternately having a first cross-sectional profile and a second cross-sectional profile, a plurality of slots being formed between the teeth; and a plurality of coils which are disposed around the teeth having the first cross-sectional profile; wherein the second cross-sectional profile has a parallel-sided stem portion and an adjoining tapered head portion, and wherein a height of the stem portion of the second cross-sectional profile is less than a height of a respective one of the coils that is disposed around an adjacent one of the teeth having the first cross-sectional profile, wherein the head portion of the second cross-sectional profile is tapered in such a way that a smallest width of the head portion is in a range from 80% to 95% of a width of the stem portion of the second cross-sectional profile, and wherein the first cross-sectional profile has a parallel-sided portion along the height of the respective one of the coils, and wherein the teeth are arranged and the head portion of the second cross-sectional profile is tapered in such a way that an outer surface of the head portion of the second cross-sectional profile is oriented parallel to an outer surface of the parallel-sided portion of the respective one of the teeth having the first cross-sectional profile that is adjacent to a same respective one of the slots; and at least one rotor disposed in the stator assembly and adapted to rotate about the central axis of the stator assembly during operation of the rotary synchronous motor.