Method and Apparatus for Electromagnetic Actuation

• US 20100033278A1
• Filed: 07/18/2007
• Published: 02/11/2010
• Est. Priority Date: 07/19/2006
• Status: Active Grant

• Current Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Original Assignee: University of Florida Research Foundation, Incorporated (State University System of Florida)
• Inventors: Agashe, Janhavi Shariniwas, Arnold, David Patrick
• Granted Patent: US 8,581,678 B2
• Time in Patent Office: Days
• US Class Current: 335/229
• CPC Class Codes: B81B 2201/038 Microengines and actuators not provided for in B81B2201/031 - B81B2201/037
• CPC Class Codes: B81B 2203/051 Translation according to an axis parallel to the substrate
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: H01H 50/005 using micromechanics
• CPC Class Codes: H02K 33/18 with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets

Abstract

Embodiments of the subject invention relate to a method and apparatus for electromagnetic actuation. Embodiments of an electromagnet actuator in accordance with the subject invention can include a fixed main body and a deformable membrane or displaceable piston-like member. In the case of piston motion, in specific embodiments, the piston can be supported by a corrugated diaphragm or bellows. In various embodiments, all or portions of the electromagnet actuator can be produced using microfabrication techniques. Specific embodiment of the subject invention can incorporate a plurality of magnets providing magnetic flux to a plurality of coil conductor elements so as to provide a plurality of locations that a force is applied to the moveable body portion of the electromagnetic actuator. Specific embodiments can incorporate an array of magnets interdigitated with an array of coil conductor elements, where the arrays can include 2, 5, 10, 20, or more each. Further specific embodiments allow the relative position of the magnetic flux and coil conductor elements to remain substantially the same during the movement of the moveable body by positioning the magnets and coil conductor elements on the moveable body so that the relative position of the magnets and the coil conductor elements on the moveable body do not change with the movement of the moveable body.

Claims

1. An electromagnetic actuator, comprising:

a main body;

a moveable body, where the moveable body is moveably attached to the main body;

a plurality of coil conductor elements, wherein the plurality of coil conductor elements are microfabricated;

a plurality of permanent magnets providing magnetic flux to the plurality of coil conductor elements, wherein the plurality of permanent magnets are microfabricated;

wherein when a current is applied to one or more of the plurality of coil conductor elements a force moves the moveable body with respect to the main body.

2. The electromagnetic actuator according to claim 1, wherein the movable body is a deformable membrane.

3. The electromagnetic actuator according to claim 1, wherein the movable body is a displaceable piston.

4. The electromagnetic actuator according to claim 1, wherein the moveable body has a circular shape.

5. The electromagnetic actuator according to claim 1, wherein the moveable body has a shaped selected from the following group:

square, rectangular, polygonal, hexagonal, and irregular.

6. The electromagnetic actuator according to claim 4, wherein the moveable body has a diameter less than 1.5 cm.

7. The electromagnetic actuator according to claim 4, wherein the moveable body has a diameter less than 1 cm.

8. The electromagnetic actuator according to claim 4, wherein the moveable body has a diameter less than 5 mm.

9. The electromagnetic actuator according to claim 4, wherein the moveable body has a thickness less than 1 mm.

10. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of coil conductor elements is less than 1 mm in one dimension.

11. The electromagnetic actuator according to claim 1, wherein the size one or more of the plurality of coil conductor elements is less than 500 μ

m in one dimension.

12. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of coil conductor elements is less than 100 μ

m in one dimension.

13. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of coil conductor elements is less than 1 mm in two dimensions.

14. The electromagnetic actuator according to claim 1, wherein the size one or more of the plurality of coil conductor elements is less than 500 μ

m in two dimensions.

15. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of coil conductor elements is less than 100 μ

m in two dimensions.

16. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 1 mm in one dimension.

17. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 500 μ

m in one dimension.

18. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 100 μ

m in one dimension.

19. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 1 mm in two dimensions.

20. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 500 μ

m in two dimensions.

21. The electromagnetic actuator according to claim 1, wherein the size of one or more of the plurality of permanent magnets is less than 100 μ

m in two dimensions.

22. The electromagnetic actuator according to claim 3, wherein the piston is moveably attached to the main body by a diaphragm.

23. The electromagnetic actuator according to claim 22, wherein the diaphragm is corrugated.

24. The electromagnetic actuator according to claim 1, wherein the plurality of coil conductor elements comprises an array of coil conductor elements and the plurality of permanent magnets comprises an array of permanent magnets.

25. The electromagnetic actuator according to claim 24, wherein the array of permanent magnets is interdigitated with the array of coil conductor elements.

26. The electromagnetic actuator according to claim 1, wherein the force that moves the moveable body with respect to the main body is applied evenly across the moveable body.

27. The electromagnetic actuator according to claim 1, wherein the relative position of the magnetic flux from the plurality of coil conductor elements remains substantially the same during movement of the moveable body with respect to the main body.

28. The electromagnetic actuator according to claim 1, wherein the plurality of permanent magnets are positioned on the main body and the plurality of coil conductor elements are positioned on the moveable body, wherein when a current is applied to the plurality of coil conductor elements, a Lorentz force on the plurality of coil conductor elements moves the moveable body with respect to the main body.

29. The electromagnetic actuator according to claim 28, wherein the plurality of permanent magnets are positioned on the main body such that the magnetic flux provided to the plurality of coil conductor elements is substantially parallel to a surface of the moveable body upon which the plurality of coil configuration elements are positioned.

30. The electromagnetic actuator according to claim 1, further comprising:

magnetically soft material positioned on the moveable body, wherein the magnetically soft material positioned on the moveable body increases the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

31. The electromagnetic actuator according to claim 1, further comprising:

additional magnetically soft material positioned on the main body, wherein the additional magnetically soft material positioned on the main body increases the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

32. The electromagnetic actuator according to claim 28, further comprising:

one or more additional permanent magnets positioned on the moveable body, wherein the one or more additional permanent magnets positioned on the moveable body so as to increase the magnetic field strength to which the plurality of coil conductor elements is exposed.

33. The electromagnetic actuator according to claim 1, wherein the plurality of coil conductor elements are positioned on the main body and the plurality of permanent magnets are positioned on the moveable body, wherein when a current is applied to the plurality of coil conductor elements, a magnetic force on the plurality of permanent magnets moves the moveable body with respect to the main body.

34. The electromagnetic actuator according to claim 29, wherein the plurality of permanent magnets are positioned on the moveable body such that the magnetic flux provided to the plurality of coil conductor elements is substantially parallel to a surface of the moveable body upon which the plurality of permanent magnets are positioned.

35. The electromagnetic actuator according to claim 1, further comprising:

magnetically soft material integrated with the electromagnetic actuator so as to increase the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

36. The electromagnetic actuator according to claim 1, wherein the plurality of coil conductor elements form a spiral coil.

37. The electromagnetic actuator according to claim 22, wherein when the moveable body moves with respect to the main body, the diaphragm provides a restoring force to move the moveable body back to an equilibrium position with respect to the main body.

38. The electromagnetic actuator according to claim 1,

wherein the plurality of coil conductor elements are positioned on the moveable body, wherein the plurality of permanent magnets are positioned on the moveable body, further comprising a soft-magnetic material positioned on the main body so as to increase the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed, wherein when a current is applied to the plurality of coil conductor elements, a Lorentz force on the plurality of coil conductor elements moves the moveable body with respect to the main body.

39. The electromagnetic actuator according to claim 1,

wherein the electromagnetic actuator is incorporated into one of the following:

a speaker, a synthetic jet, a valve, a linear motor, a microspeaker, a flow-control actuator, a micropump, or a microvalve.

40. A method of producing an electromagnetic actuator, comprising:

producing an electromagnetic actuator comprising;

a main body;

a moveable body, where the moveable body is moveably attached to the main body;

a plurality of coil conductor elements, wherein the plurality of coil conductor elements are microfabricated;

a plurality of permanent magnets providing magnetic flux to the plurality of coil conductor elements, wherein the plurality of permanent magnets are microfabricated;

wherein when a current is applied to one or more of the plurality of coil conductor elements a force moves the moveable body with respect to the main body, wherein the electromagnetic actuator producing via microfabrication techniques.

41. A method of electromagnetic actuation, comprising:

providing an electromagnetic actuator comprising;

a main body;

a moveable body, where the moveable body is moveably attached to the main body;

a plurality of coil conductor elements, wherein the plurality of coil conductor elements are microfabricated;

a plurality of permanent magnets providing magnetic flux to the plurality of coil conductor elements, wherein the plurality of permanent magnets are microfabricated;

wherein when a current is applied to one or more of the plurality of coil conductor elements a force moves the moveable body with respect to the main body,

applying a current to one or more of the plurality of coil conductor elements.

42. The method according to claim 41, wherein the movable body is a deformable membrane.

43. The method according to claim 41, wherein the movable body is a displaceable piston.

44. The method according to claim 41, wherein the moveable body has a circular shape.

45. The method according to claim 41, wherein the moveable body has a shaped selected from the following group:

square, rectangular, polygonal, hexagonal, and irregular.

46. The method according to claim 44, wherein the moveable body has a diameter less than 1.5 cm.

47. The method according to claim 44, wherein the moveable body has a diameter less than 1 cm.

48. The method according to claim 44, wherein the moveable body has a diameter less than 5 mm.

49. The method according to claim 44, wherein the moveable body has a thickness less than 1 mm.

50. The method according to claim 41, wherein the size of one or more of the plurality of coil conductor elements is less than 1 mm in one dimension.

51. The method according to claim 41, wherein the size one or more of the plurality of coil conductor elements is less than 500 μ

m in one dimension.

52. The method according to claim 41, wherein the size of one or more of the plurality of coil conductor elements is less than 100 μ

m in one dimension.

53. The method according to claim 41, wherein the size of one or more of the plurality of coil conductor elements is less than 1 mm in two dimensions.

54. The method according to claim 41, wherein the size one or more of the plurality of coil conductor elements is less than 500 μ

m in two dimensions.

55. The method according to claim 41, wherein the size of one or more of the plurality of coil conductor elements is less than 100 μ

m in two dimensions.

56. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 1 mm in one dimension.

57. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 500 μ

m in one dimension.

58. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 100 μ

m in one dimension.

59. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 1 mm in two dimensions.

60. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 500 μ

m in two dimensions.

61. The method according to claim 41, wherein the size of one or more of the plurality of permanent magnets is less than 100 μ

m in two dimensions.

62. The method according to claim 43, wherein the piston is moveably attached to the main body by a diaphragm.

63. The method according to claim 62, wherein the diaphragm is corrugated.

64. The method according to claim 41, wherein the plurality of coil conductor elements comprises an array of coil conductor elements and the plurality of permanent magnets comprises an array of permanent magnets.

65. The method according to claim 64, wherein the array of permanent magnets is interdigitated with the array of coil conductor elements.

66. The method according to claim 41, wherein the force that moves the moveable body with respect to the main body is applied evenly across the moveable body.

67. The method according to claim 41, wherein the relative position of the magnetic flux from the plurality of coil conductor elements remains substantially the same during movement of the moveable body with respect to the main body.

68. The method according to claim 41, wherein the plurality of permanent magnets are positioned on the main body and the plurality of coil conductor elements are positioned on the moveable body, wherein when a current is applied to the plurality of coil conductor elements, a Lorentz force on the plurality of coil conductor elements moves the moveable body with respect to the main body.

69. The method according to claim 68, wherein the plurality of permanent magnets are positioned on the main body such that the magnetic flux provided to the plurality of coil conductor elements is substantially parallel to a surface of the moveable body upon which the plurality of coil configuration elements are positioned.

70. The method according to claim 41, further comprising:

magnetically soft material positioned on the moveable body, wherein the magnetically soft material positioned on the moveable body increases the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

71. The method according to claim 41, further comprising:

additional magnetically soft material positioned on the main body, wherein the additional magnetically soft material positioned on the main body increases the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

72. The method according to claim 68, further comprising:

one or more additional permanent magnets positioned on the moveable body, wherein the one or more additional permanent magnets positioned on the moveable body so as to increase the magnetic field strength to which the plurality of coil conductor elements is exposed.

73. The method according to claim 41, wherein the plurality of coil conductor elements are positioned on the main body and the plurality of permanent magnets are positioned on the moveable body, wherein when a current is applied to the plurality of coil conductor elements, a magnetic force on the plurality of permanent magnets moves the moveable body with respect to the main body.

74. The method according to claim 69, wherein the plurality of permanent magnets are positioned on the moveable body such that the magnetic flux provided to the plurality of coil conductor elements is substantially parallel to a surface of the moveable body upon which the plurality of permanent magnets are positioned.

75. The method according to claim 41, further comprising:

magnetically soft material integrated with the electromagnetic actuator so as to increase the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed.

76. The method according to claim 41, wherein the plurality of coil conductor elements form a spiral coil.

77. The method according to claim 62, wherein when the moveable body moves with respect to the main body, the diaphragm provides a restoring force to move the moveable body back to an equilibrium position with respect to the main body.

78. The method according to claim 41,

wherein the plurality of coil conductor elements are positioned on the moveable body, wherein the plurality of permanent magnets are positioned on the moveable body, further comprising a soft-magnetic material positioned on the main body so as to increase the magnetic field strength, due to the plurality of permanent magnets, to which at least one of the plurality of coil conductor elements is exposed, wherein when a current is applied to the plurality of coil conductor elements, a Lorentz force on the plurality of coil conductor elements moves the moveable body with respect to the main body.

79. The method according to claim 41,

wherein the electromagnetic actuator is incorporated into one of the following:

a speaker, a synthetic jet, a valve, a linear motor, a microspeaker, a flow-control actuator, a micropump, or a microvalve.