Plastic pole housing for an electric motor

• US 8,040,005 B2
• Filed: 02/08/2008
• Issued: 10/18/2011
• Est. Priority Date: 02/08/2008
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH, Robert Bosch LLC (Robert Bosch GmbH)
• Original Assignee: Robert Bosch GmbH
• Inventors: Bhatti, Irfan A.
• Primary Examiner(s): Leung; Quyen
• Assistant Examiner(s): DESAI, NAISHADH N
• Application Number:
  US12/069,341
• Publication Number:
  US 20090200881A1
• Time in Patent Office: 1,348 Days
• Field of Search: 310/154.08, 310/9, 310/154.07, 310/89, 310/88, 310/154
• US Class Current: 310/154.09
• CPC Class Codes: H02K 1/17 Stator cores with permanent magnets
• CPC Class Codes: H02K 5/02 Casings or enclosures characterised by the material thereof
• CPC Class Codes: H02K 5/08 Insulating casings
• CPC Class Codes: H02K 5/10 with arrangements for protection from ingress, e.g. water or fingers
• CPC Class Codes: H02K 5/1672 radially supporting the rotary shaft at both ends of the rotor H02K5/1677 takes precedence
• CPC Class Codes: H02K 5/24 specially adapted for suppression or reduction of noise or vibrations

Abstract

A housing assembly for an electric motor includes a sealed plastic enclosure having a body portion having a nose and an open end opposite from the nose. The open end provides access to an interior region of the plastic enclosure. The housing assembly also includes a metal sleeve located within the interior region of the plastic enclosure, and a magnet structure located within an interior region of the metal sleeve.

Claims

1. A housing assembly for an electric motor, the housing assembly comprising:

a sealed plastic enclosure including a body portion having a nose and an open end opposite from the nose, the open end providing access to an interior region of the plastic enclosure;

a metal sleeve located within the interior region of the plastic enclosure; and

a magnet structure located within an interior region of the metal sleeve.

2. The housing assembly of claim 1, wherein the metal sleeve is formed from a single sheet of metal material having tabs at a first end cooperating with slots at a second end to form the metal sleeve.

3. The housing assembly of claim 1, wherein the metal sleeve is formed from first and second separate metal sheets.

4. The housing assembly of claim 3, wherein the first and second separate metal sheets include tabs configured to couple the first and second metal sheets together to form the metal sleeve.

5. The housing assembly of claim 3, wherein the first and second metal sheets are identically shaped.

6. The housing assembly of claim 1, wherein the magnet structure includes first and second permanent magnets located within the interior region of the metal sleeve.

7. The housing assembly of claim 6, further comprising at least one spring clip located within the interior region of the metal sleeve to hold the first and second permanent magnets within the metal sleeve.

8. The housing assembly of claim 1, further comprising a bearing located in the nose of the plastic enclosure, the bearing being configured to receive a shaft of an armature of the electric motor.

9. The housing assembly of claim 1, further comprising a plurality of crush ribs formed on an inner surface of the plastic enclosure.

10. The housing assembly of claim 9, wherein the crush ribs include a lead-in ramp surface adjacent the open end of the plastic enclosure and an elongated body portion extending longitudinally along the inner surface of the plastic enclosure.

11. The housing assembly of claim 1, wherein the plastic enclosure is formed from a material capable of operating at temperatures ranging from about −

40°

C. to about 85°

C.

12. The housing assembly of claim 1, wherein the plastic enclosure is formed from a material capable of withstanding a thermal shock of at least 110°

C.

20. The housing assembly of claim 1, wherein the nose of the body portion of the sealed plastic enclosure is configured to support a shaft of an armature therein, the metal sleeve surrounding the armature.

21. The housing assembly of claim 20, further comprising one of a bushing and a bearing press-fit into a pocket formed by the nose of the body portion of the sealed plastic enclosure to support the shaft of the armature.

22. The housing assembly of claim 20, wherein the shaft of the armature directly engages a pocket formed by the nose of the body portion of the sealed plastic enclosure.

13. A housing assembly for an electric motor, the housing assembly comprising:

a plastic enclosure including a body portion having an outer surface and an inner surface defining an interior region, the body portion also having a nose and an open end opposite from the nose, the open end providing access to the interior region of the plastic enclosure;

a plurality of crush ribs formed on the inner surface of the plastic enclosure, the crush ribs including an elongated body portion extending longitudinally along the inner surface of the plastic enclosure and a lead-in ramp surface located adjacent the open end of the plastic enclosure, the lead-in ramp surface extending from the inner surface of the plastic enclosure to a height of the elongated body portion;

a metal sleeve located within the interior region of the plastic enclosure, the metal sleeve being configured to engage the plurality of crush ribs; and

a magnet structure located within an interior region of the metal sleeve.

14. The housing assembly of claim 13, wherein the plastic enclosure is sealed to prevent water from entering the interior region of the plastic enclosure.

15. The housing assembly of claim 13, wherein the metal sleeve is formed from separate first and second metal sheets.

16. The housing assembly of claim 13, wherein the plastic enclosure is formed from a material capable of withstanding a thermal shock of at least 110°

C.

23. The housing assembly of claim 13, wherein the body portion of the plastic enclosure has a cylindrical shape and the plurality of crush ribs are spaced apart around the inner surface so crush ribs are located on opposing portions of the inner surface to engage opposite sides of the metal sleeve.

24. The housing assembly of claim 23, wherein certain of the crush ribs on the inner surface are displaced more than other crush ribs during insertion of the metal sleeve into the interior region of the plastic enclosure due to irregularities of at least one of the plastic enclosure and the metal sleeve.

25. The housing assembly of claim 23, wherein at least 10 crush ribs are spaced apart on the inner surface of the body portion of the plastic enclosure.

26. The housing assembly of claim 23, wherein at least 20 crush ribs are spaced apart on the inner surface of the body portion of the plastic enclosure.

27. The housing assembly of claim 23, wherein the height of the body portion of the crush ribs is about 0.25 mm.

28. The housing assembly of claim 27, wherein a width of the body portion of the crush ribs is about 0.25 mm.

17. A housing assembly for an electric motor, the housing assembly comprising:

a plastic enclosure including a body portion having a nose and an open end opposite from the nose, the open end providing access to an interior region of the plastic enclosure;

a metal sleeve located within the interior region of the plastic enclosure, the metal sleeve being formed from separate first and second identically shaped metal sheets; and

a magnet structure located within an interior region of the metal sleeve.

18. The housing assembly of claim 17, wherein the plastic enclosure is sealed to prevent water from entering the interior region of the plastic enclosure.

19. The housing assembly of claim 17, wherein the body portion of the plastic enclosure includes an outer surface and an inner surface defining the interior region of the plastic enclosure, and further comprising a plurality of crush ribs formed on the inner surface of the plastic enclosure.

29. The housing assembly of claim 17, wherein the first and second metal sheets each include a first end having a first connecting portion a second end having a second connecting portion shaped differently than and complementary to the first connecting portion.

30. The housing assembly of claim 29, wherein the first connecting portions include a pair of outer tabs defining a recess adjacent the first end of the first and second sheets and the second connecting portions include an inner tab formed adjacent the second end of the first and second sheets, the inner tabs being configured to fit within the recess to provide the metal sleeve when the first and second metal sheets are assembled together.

31. The housing assembly of claim 29, wherein the first and second ends of the first and second metal sheets abut the second and first ends, respectively, of the other of the first and second metal sheets to provide a continuous metal sleeve without gaps between the first and second metal sheets.