Alignment of segmented stators for electric machines

• US 8,018,115 B2
• Filed: 08/31/2009
• Issued: 09/13/2011
• Est. Priority Date: 11/22/2005
• Status: Active Grant

• Current Assignee: Nidec Motor Corporation (Nidec Corporation)
• Original Assignee: Nidec Motor Corporation (Nidec Corporation)
• Inventors: Lyle, David M.
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US12/551,050
• Publication Number:
  US 20100109470A1
• Time in Patent Office: 743 Days
• Field of Search: 310/214, 310/215, 310216001-216137
• US Class Current: 310/216.009
• CPC Class Codes: H02K 3/522 for generally annular cores with salient poles

Abstract

A stator segment for a segmented stator of an electric machine includes insulative material configured for overlapping with insulative material of an adjacent stator segment to provide continuous insulation along a joint between the adjacent stator segments. Additionally, or alternatively, the stator segment can include one or more alignment tabs configured to engage a surface of an adjacent stator segment to inhibit relative axial movement between adjacent stator segments.

Claims

1. A stator segment for a segmented stator, the stator segment comprising a yoke portion, a tooth portion, and a first tab extending from the yoke portion beyond a first side edge of the yoke portion, the first tab configured to overlie a portion of an adjacent stator segment and to engage an insulative surface of said adjacent stator segment when assembled together in the segmented stator to thereby inhibit relative axial movement between the adjacent stator segments, further comprising a second tab extending from the yoke portion and configured to engage a surface of an adjacent stator segment when assembled together in the segmented stator, wherein the second tab is configured to engage a core surface of an adjacent stator segment.

2. The stator segment of claim 1 wherein the first tab comprises an insulative material molded over the yoke portion.

3. The stator segment of claim 1 wherein the first and second tabs are positioned on opposite side edges of the yoke portion.

4. The stator segment of claim 3 wherein the first and second tabs are configured to releasably secure the stator segment to adjacent stator segments.

5. The stator segment of claim 1 wherein the first tab is configured to extend over a joint between the adjacent stator segments when assembled together in the segmented stator.

6. The stator segment of claim 1 wherein the first tab comprises an insulative end cap positioned on the yoke portion.

7. The stator segment of claim 1 wherein the first tab is the only tab extending from an end of the yoke portion on which the first tab is positioned.

8. The stator segment of claim 1 wherein the second tab is configured to engage a core surface of an adjacent stator segment when assembled together in the segmented stator.

9. The stator segment of claim 1 wherein the first tab extends from a first axial end of the yoke portion and the second tab extends from a second axial end of the yoke portion opposite the first axial end.

10. The stator segment of claim 9 wherein the second tab extends beyond a second side edge of the yoke portion opposite the first side edge.

11. The stator segment of claim 1 further comprising an insulative material on the yoke portion.

12. The stator segment of claim 11 wherein the insulative material is configured for overlapping with insulative material of an adjacent stator segment when assembled together in the segmented stator to provide substantially continuous insulation along a joint between adjacent stator segments.

13. The stator segment of claim 12 wherein the insulative material defines one of a tongue and a groove for overlapping with a groove or a tongue, respectively, of an adjacent stator segment.

14. The stator segment of claim 11 wherein the insulative material defines one of a tongue and a groove for overlapping with a groove or a tongue, respectively, of an adjacent stator segment.

15. The stator segment of claim 14 wherein the insulative material of at least one stator segment defines a tongue and the insulative material of an adjacent stator segment defines a groove, the tongue being received within the groove.

16. A segmented stator for an electric machine, the stator comprising a plurality of annularly arranged stator segments, each stator segment including a yoke portion, a tooth portion, and a first tab and a second tab extending from the yoke portion, the first tab of each stator segment engaging a surface of an adjacent stator segment to inhibit relative axial movement between the plurality of stator segments, the second tab engaging a surface of an adjacent stator segment, wherein the first and second tabs of each stator segment are positioned on opposite ends of the yoke portion, wherein each stator segment comprises an insulative material molded over the yoke portion, and wherein the insulative material of at least one stator segment overlaps the insulative material of an adjacent stator segment along a joint between adjacent stator segments.

17. The segmented stator of claim 16 wherein the first tab of each stator segment comprises an insulative material molded over the yoke portion.

18. The segmented stator of claim 16 wherein the first and second tabs of each stator segment are configured to releasably secure the stator segment to adjacent stator segments.

19. The segmented stator of claim 16 wherein the first tab of each stator segment extends over a joint the joint between adjacent stator segments.

20. The segmented stator of claim 16 wherein on an end of each stator segment on which the first tab is positioned, the first tab is the only tab that engages a surface of an adjacent stator segment.

21. The segmented stator of claim 16 wherein the second tab engages a core surface of an adjacent stator segment.

22. The segmented stator of claim 16 wherein the insulative material of at least one stator segment defines a tongue and the insulative material of an adjacent stator segment defines a groove, the tongue being received within the groove.

23. An electric machine comprising the segmented stator of claim 16.