Polarized magnetic actuators for haptic response

• US 9,928,950 B2
• Filed: 09/27/2013
• Issued: 03/27/2018
• Est. Priority Date: 09/27/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Lubinski, Nicholaus Ian, Wright, James E., Harley, Jonah A., Brock, John M., Hendren, Keith J., Hoen, Storrs T.
• Primary Examiner(s): Rojas, Bernard
• Application Number:
  US15/025,254
• Publication Number:
  US 20160233012A1
• Time in Patent Office: 1,642 Days
• CPC Class Codes: H01F 2007/1661 Electromagnets or actuators with anti-stick disc
• CPC Class Codes: H01F 41/02 for manufacturing cores, coils, or magnets H01F41/14 takes precedence; for dynamo-electric machines H02K15/00
• CPC Class Codes: H01F 7/12 having anti-chattering arrangements
• CPC Class Codes: H01F 7/122 by permanent magnets H01F7/1615, H01F7/1646 take precedence
• CPC Class Codes: H01F 7/14 Pivoting armatures H01F7/17 takes precedence
• CPC Class Codes: H01F 7/16 Rectilinearly-movable armatures H01F7/17 takes precedence
• CPC Class Codes: H01F 7/1646 Armatures or stationary parts of magnetic circuit having permanent magnet

Abstract

A polarized electromagnetic actuator includes a movable armature, a stator, and at least one coil wrapped around the stator. At least one permanent magnet is disposed over the stator. When a current is applied to the at least one coil, the at least one coil is configured to reduce a magnetic flux of at least one permanent magnet in one direction and increase a magnetic flux of at least one permanent magnet in another direction. The movable armature moves in the direction of the increased magnetic flux.

Claims

1. A polarized electromagnetic actuator, comprising:

a stator including two tines extending out from the stator;

a movable armature disposed over the two tines of the stator;

a first stabilizing element connecting the movable armature and the stator;

a second stabilizing element connecting the movable armature and the stator;

a first coil positioned around one tine;

a second coil positioned around the other tine;

a first permanent magnet disposed over the stator between the two tines, wherein a magnetic flux of the first and the second coils increases a magnetic flux of the first permanent magnet in one direction to produce motion in the movable armature; and

a second permanent magnet disposed over the stator between the two tines;

wherein

the first stabilizing element is disposed around a first end of the stator and a first end of the moveable armature; and

the second stabilizing element is disposed around a second end of the stator and a second end of the moveable armature.

2. The polarized electromagnetic actuator as in claim 1, further comprising a pivot disposed between the permanent magnet and the movable armature.

3. The polarized electromagnetic actuator as in claim 1, further comprising a pivot disposed between the movable armature and the stator and between the first and second permanent magnets.

4. The polarized electromagnetic actuator of claim 1, wherein the first and second stabilizing elements cause the polarized electromagnetic actuator to be stable at zero displacement of the armature.

5. A polarized electromagnetic actuator, comprising:

a stator including two tines extending out from the stator;

a movable armature positioned between the two tines of the stator;

a first coil positioned around one tine;

a second coil positioned around the other tine; and

a permanent magnet disposed under the movable armature and over the stator between the two tines, wherein a magnetic flux of the first and second coils increases a magnetic flux of the permanent magnet in one direction to produce motion in the movable armature.

6. The polarizing electromagnetic actuator as in claim 5, further comprising one or more stabilizing elements disposed between the permanent magnet and the movable armature.

7. The polarizing electromagnetic actuator as in claim 5, further comprising one or more stabilizing elements disposed between the movable armature and at least one tine of the stator.

8. The polarizing electromagnetic actuator as in claim 5, further comprising one or more bending flexures disposed between the stator and the movable armature.

9. A polarized electromagnetic actuator, comprising:

a movable armature including two tines extending out from the armature;

a stator disposed over the two tines of the movable armature;

a permanent magnet disposed under the stator and over the movable armature between the two tines;

a first coil positioned around the stator between one tine of the armature and the permanent magnet; and

a second coil positioned around the stator between the other tine and the permanent magnet.

10. A polarized electromagnetic actuator, comprising:

a stator including two tines extending out from the stator;

a coil positioned around the stator between the two tines;

a first permanent magnet disposed over one tine of the stator;

a second permanent magnet disposed over the other tine of the stator; and

a movable armature including a first arm disposed over the first permanent magnet and a second arm disposed over the second permanent magnet and a body disposed between the two tines, wherein a magnetic flux of the coil increases a magnetic flux of one permanent magnet to produce motion in the movable armature in a direction of the increased magnetic flux.

11. The polarized electromagnetic actuator as in claim 10, further comprising at least one stabilizing element disposed between the body of the movable armature and at least one tine of the stator.

12. The polarized electromagnetic actuator as in claim 10, further comprising at least one stabilizing element disposed between at least one permanent magnet and a respective arm of the movable armature.

13. A polarized electromagnetic actuator, comprising:

a stator including two tines extending out from the stator;

a coil positioned around the stator between the two tines;

a movable armature including;

a first arm disposed over one tine of the stator;

a second arm disposed over the other tine of the stator; and

a body disposed between the two tines;

a first permanent magnet attached to the first arm of the movable armature and disposed over one tine of the stator; and

a second permanent magnet attached to the second arm of the movable armature and disposed over the other tine of the stator,

wherein a magnetic flux of the coil increases a magnetic flux of one permanent magnet to produce motion in the movable armature in a direction of the increased magnetic flux.

14. The polarized electromagnetic actuator as in claim 13, further comprising at least one stabilizing element attached to an outer end of a respective arm of the armature and the stator.

15. A method for providing a polarized electromagnetic actuator comprising:

providing a stator that includes two tines extending out from the stator;

providing a movable armature between the two tines of the stator;

providing a first coil positioned around a first tine of the stator and a second coil positioned around a second tine of the stator;

providing at least one permanent magnet under the movable armature and over the stator between the two tines; and

configuring the at least one coil to increase a magnetic flux of the at least one permanent magnet in one direction when a current is applied to the at least one coil, wherein the movable armature moves in the direction of the increased magnetic flux.

16. The method as in claim 15, further comprising providing one or more stabilizing elements to ends of the movable armature to stabilize the movable armature when a current is not applied to the at least one coil.

18. The method as in claim 15, further comprising providing one or more stabilizing elements to the permanent magnet to stabilize the movable armature when a current is not applied to the at least one coil.

19. The method as in claim 15, further comprising providing one or more stabilizing elements connecting the stator to the movable armature to stabilize the movable armature when a current is not applied to the at least one coil.

20. The method as in claim 15, wherein the one or more stabilizing elements provided to ends of the movable armature are connected to the stator.

17. A polarized electromagnetic actuator, comprising:

a stator including two tines extending out from the stator;

a coil positioned around the stator between the two tines;

a movable armature including a first arm disposed over one tine of the stator, a second arm disposed under the other tine of the stator, and a body disposed between the two tines;

a first permanent magnet attached to one tine of the stator; and

a second permanent magnet attached to the other tine of the stator, wherein the coil produces a first magnetic flux when a current is applied to the coil and the magnetic flux of the coil increases a magnetic flux of one permanent magnet to produce motion in the movable armature in a direction of the increased magnetic flux.

21. A method for providing a polarized electromagnetic actuator comprising:

providing a stator that includes two tines extending out from the stator;

providing a movable armature spaced having an arm disposed over each tine of the stator and body disposed between the two tines of the stator;

providing at least one coil positioned around the stator between the two tines;

providing a first permanent magnet between a first arm of the movable armature and a first tine of the stator that the arm is disposed over;

providing a second permanent magnet between a second arm of the movable armature and a second tine of the stator that the arm is disposed over; and

configuring the at least one coil to increase a magnetic flux of at least one permanent magnet in one direction when a current is applied to the at least one coil, wherein the movable armature moves in the direction of the increased magnetic flux.

22. The method of claim 21, wherein the first permanent magnetic is attached to the first arm of the movable armature and the second permanent magnet is attached to the second arm of the movable armature.

23. The method of claim 21, wherein the first permanent magnetic is attached to the first tine of the stator and the second permanent magnet is attached to the second tine of the stator.

24. The method of claim 21, further comprising providing one or more stabilizing elements to the body of the movable armature to stabilize the movable armature when a current is not applied to the at least one coil.