Rotatable assemblies having chemically bonded lamination stacks

• US 20050034295A1
• Filed: 07/03/2004
• Published: 02/17/2005
• Est. Priority Date: 10/16/1997
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Menon, M. N., Meacham, Walter L.
• Granted Patent: US 7,224,096 B2
• Time in Patent Office: Days
• US Class Current: 29/598
• CPC Class Codes: F16C 32/0468 of moving parts of the magnetic circuit, e.g. of the rotor
• CPC Class Codes: H02K 1/02 characterised by the magnetic material
• CPC Class Codes: H02K 1/04 characterised by the material used for insulating the magnetic circuit or parts thereof
• CPC Class Codes: H02K 1/06 characterised by the shape, form or construction
• CPC Class Codes: H02K 1/24 Rotor cores with salient poles ; Variable reluctance rotors
• CPC Class Codes: H02K 15/02 of stator or rotor bodies
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine
• CPC Class Codes: Y10T 29/49012 Rotor

Abstract

A rotor assembly or other rotating device having a stack of laminations or laminates that are chemically bonded together. Chemical bond of the laminates may have a strength that approaches the strength of the material of metal laminates. Chemical bonds may be effective in holding the laminates at temperatures when subject to rigorous mechanical operations such as high rotation speed and vibration.

Claims

1. A rotatable assembly for a machine, comprising:

a stack of laminations, each lamination formed from a material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent such that the laminations maintain a bond at operating temperatures over 1000 degrees Fahrenheit.

2. The assembly of claim 1, wherein the chemical bonding agent is selected from a group consisting of glass, metallic-oxides, silicates and nitrides of silicon.

3. The assembly of claim 1, wherein the chemical bonding agent is a material having a low dielectric constant.

4. The assembly of claim 1, wherein the material is a soft magnetic material.

7. The assembly of claim 1, wherein the laminations and the chemical bonding agent have matching coefficients of thermal expansion.

8. The assembly of claim 1, the chemical bonding agent provides magnetic insulation between the bonded laminations.

9. The assembly of claim 1, further comprising a metallic layer on the surfaces of each of the laminations.

10. The assembly of claim 9, wherein the metallic layer is an interface to protect lamination from oxidation and to chemically bond with the dielectric bonding agent.

11. The assembly of claim 1, further comprising:

first and second end caps bonded to the laminations by the chemical bonding agent; and

a shaft bonded by the chemical bonding agent to a bore defined by the laminations.

71. The assembly of claim 1, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.

5. The assembly of claim 5, wherein the soft magnetic material is iron-cobalt.

6. The assembly of claim 5, wherein the soft magnetic material is silicon steel.

12. A machine comprising:

a housing;

a stator assembly mounted to the housing; and

a rotor assembly including a shaft, a stack of laminations mounted to the shaft, each lamination formed from a material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent, such that the laminations maintain a bond in operating temperatures over 1000 degrees Fahrenheit, the shaft being bonded to the stack of laminations by the chemical bonding agent.

13. The machine of claim 12, wherein the chemical bonding agent is selected from a group consisting of glass, metallic-oxides, silicates, and nitrides of silicon.

14. The machine of claim 12, wherein the chemical bonding agent is a material having a low dielectric constant.

15. The machine of claim 12, wherein the material is a soft magnetic material.

16. The machine of claim 15, wherein the soft magnetic material is iron-cobalt.

17. The machine of claim 15, wherein the soft magnetic material is silicon steel.

18. The machine of claim 12, wherein the laminations and the chemical bonding agent have matching coefficients of thermal expansion.

19. The machine of claim 12, wherein the bonding agent provides magnetic insulation between the laminations.

20. The machine of claim 12, further comprising:

first and second end caps bonded to the laminations by the chemical bonding agent; and

a plurality of bearings for supporting the rotor assembly within the housing.

72. The machine of claim 12, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.

21. A method of fabricating a rotor assembly, comprising:

applying a chemical bonding agent to surfaces of a plurality of laminations;

stacking the plurality of laminations; and

applying a thermal cycle to the stack of laminations of sufficient temperature to cure the chemical bonding agent such that the laminations maintain a bond in operating temperatures over 1000 degrees Fahrenheit.

22. The method of claim 21, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon.

23. The method of claim 21, further comprising of applying a pressure load to the stacked laminations during the thermal cycle.

24. The method of claim 23, further comprising applying the chemical bonding agent to end caps, stacking the end caps along with the laminations, and applying the pressure load to the end caps during the thermal cycle.

25. The method of claim 24, further comprising machining geometric forms into the lamination stack after the laminations have been bonded.

26. The method of claim 21, wherein the chemical bonding agent and the laminations have substantially matching coefficients of thermal expansion.

27. A method of fabricating a rotor assembly, comprising:

annealing a plurality of laminations;

applying a chemical bonding agent to surfaces of each lamination of the plurality of laminations;

applying a chemical bonding agent to the surfaces of end caps;

stacking the plurality of laminations into a stack;

placing one end cap at each end of the stack;

applying pressure on both end caps to compress the stack;

heating the stack and the end caps to a temperature sufficient to cure the chemical bonding agent, such that the cured chemical bonding agent is able to maintain the bond of the stack and of the end caps at operating temperatures over 1000 degrees F; and

removing the heating and pressure from the end caps and the stack.

28. The method of claim 27, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon.

29. The method of claim 27, wherein the chemical bonding agent and the laminations have similar thermal coefficients of expansion.

30. The method of claim 27, wherein each lamination of the rotor assembly is one piece of metal.

31. The method of claim 30, wherein the surface of each end cap facing the stack is essentially flat.

32. The method of claim 30, wherein the one piece of metal is a soft magnetic material.

33. The method of claim 32, further comprising polishing the surfaces of each lamination prior to applying the chemical bonding agent to the surfaces of each lamination.

34. The method of claim 33, further comprising annealing each lamination prior to applying the chemical bonding agent to the surfaces of each lamination.

35. A method of fabricating a rotor assembly, comprising:

annealing each of a plurality of laminations;

applying a chemical bonding agent to the surfaces of each lamination of the plurality of laminations;

stacking the laminations; and

applying a thermal cycle to the stacked laminations to cure the chemical bonding agent, and wherein the temperature at which the thermal cycle is performed provides a cured bond that can endure operating temperatures over 1000 degrees Fahrenheit.

36. The method of claim 35, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and silicon nitrides.

37. The method of claims 35, further comprising applying a pressure load to the stacked laminations during the thermal cycle.

38. The method of claim 37, further comprising:

applying the chemical bonding agent to end caps;

stacking the end caps at each end of the stacked laminations; and

additionally applying the pressure load to the end caps during the thermal cycle.

39. The method of claim 38, further comprising removing excess bonding agent from the stacked laminations.

40. The method of claim 35, wherein the thermal coefficients of thermal expansion of the chemical bonding agent and the laminations are approximately equal.

41. A rotor assembly for a machine, comprising:

a stack of laminations, each lamination formed from a material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent, such that the laminations maintain a bond in operating temperatures up to 1000 degrees Fahrenheit, and the laminations and the chemical bonding agent having substantially matching coefficients of thermal expansion, the bonding agent providing magnetic insulation between the bonded laminations.

42. The assembly of claim 41, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon.

43. The assembly of claim 41, wherein the chemical bonding agent is a material having a low dielectric constant.

44. The assembly of claim 41, wherein the material is a soft magnetic material.

45. The assembly of claim 44 wherein the soft magnetic material is iron-cobalt.

46. The assembly of claim 44, wherein the soft magnetic material is silicon steel.

47. The assembly of claim 41, further comprising:

first and second end caps bonded to the laminations by the chemical bonding agent; and

a shaft bonded by the chemical bonding agent to a bore defined by the laminations.

73. The assembly of claim 41, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.

48. A machine comprising:

a housing;

a stator assembly mounted to the housing; and

a rotor assembly including a shaft, a stack of laminations mounted to the shaft, each lamination formed from a soft magnetic material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent, such that the laminations maintain a bond in operating temperatures up to 1000 degrees Fahrenheit, and the laminations and the chemical bonding agent having matching coefficients of thermal expansion, the shaft being bonded to the stack of laminations by the chemical bonding agent;

49. The machine of claim 48, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon

50. The machine of claim 48, wherein the chemical bonding agent is a having a low dielectric constant.

51. The machine of claim 48, wherein the soft magnetic material is iron-cobalt.

52. The machine of claim 48, wherein the soft magnetic material is silicon steel.

53. The machine of claim 50, wherein the bonding agent provides magnetic insulation between the laminations.

54. The machine of claim 50, further comprising:

first and second end caps bonded to the laminations by the chemical bonding agent; and

a plurality of bearings for supporting the rotor assembly within the housing.

74. The machine of claim 48, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.

55. A machine comprising:

a housing;

a rotor assembly including a shaft,

a stator assembly mounted to the housing, having a stack of laminations, each lamination formed from a soft magnetic material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent, such that the laminations maintain a bond in operating temperatures up to 1000 degrees Fahrenheit, and the laminations and the chemical bonding agent having matching coefficients of thermal expansion, the shaft being bonded to the stack of laminations by the chemical bonding agent;

56. The machine of claim 55, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon

57. The machine of claim 55, wherein the chemical bonding agent is a having a low dielectric constant.

58. The machine of claim 55, wherein the soft magnetic material is iron-cobalt.

59. The machine of claim 55, wherein the soft magnetic material is silicon steel.

60. The machine of claim 57, wherein the bonding agent provides magnetic insulation between the laminations.

61. The machine of claim 57, further comprising first and second end caps bonded to the laminations by the chemical bonding agent.

62. The machine of claim 57, further comprising a sleeve or housing bonded to an outer diameter or inner diameter of the laminations by the chemical bonding agent.

75. The machine of claim 55, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.

63. A machine comprising:

a housing;

a rotor assembly including a shaft,

a stator assembly mounted to the housing, having a stack of laminations, each lamination formed from a soft magnetic material; and

a chemical bonding agent disposed over axial facing surfaces of each of the laminations, the laminations being bonded together by the chemical bonding agent, such that the laminations maintain a bond in operating temperatures over 1000 degrees Fahrenheit, and the laminations and the chemical bonding agent having matching coefficients of thermal expansion, the shaft being bonded to the stack of laminations by the chemical bonding agent;

64. The machine of claim 63, wherein the chemical bonding agent is selected from a group consisting of metallic oxides, glass, silicates, and nitrides of silicon

65. The machine of claim 63, wherein the chemical bonding agent is a having a low dielectric constant.

66. The machine of claim 63, wherein the soft magnetic material is iron-cobalt.

67. The machine of claim 63, wherein the soft magnetic material is silicon steel.

68. The machine of claim 65, wherein the bonding agent provides magnetic insulation between the laminations.

69. The machine of claim 65, further comprising first and second end caps bonded to the laminations by the chemical bonding agent.

70. The machine of claim 65, further comprising a sleeve or housing bonded to an outer diameter or inner diameter of the laminations by the chemical bonding agent.

76. The machine of claim 63, wherein a chemical bonding agent is disposed over radial facing surfaces of each of the laminations.