ELECTRONIC DEVICE INCLUDING MULTI-PHASE DRIVEN LINEAR HAPTIC ACTUATOR AND RELATED METHODS

• US 20180059793A1
• Filed: 07/25/2017
• Published: 03/01/2018
• Est. Priority Date: 08/31/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: HAJATI, Arman
• Granted Patent: US 10,890,973 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 1/163 Wearable computers, e.g. on a belt
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: H02K 1/34 Reciprocating, oscillating or vibrating parts of the magnetic circuit
• CPC Class Codes: H02K 33/02 with armatures moved one way by energisation of a single coil system and returned by mechanical force, e.g. by springs
• CPC Class Codes: H02K 33/16 with polarised armatures moving in alternate directions by reversal or energisation of a single coil system
• CPC Class Codes: H04M 19/047 Vibrating means for incoming calls

Abstract

An electronic device may include a linear haptic actuator that may include a housing, coils carried by the housing, and a field member linearly movable within the housing and that may include at least one permanent magnet cooperating with the coils. The electronic device may also include a controller configured to drive the coils in a multi-phase arrangement so that at least one coil is driven while at least one other coil is used to sense a position of the field member.

Claims

1. An electronic device comprising:

a linear haptic actuator comprising

a housing,

a plurality of coils carried by the housing, and

a field member linearly movable within the housing and comprising at least one permanent magnet cooperating with the plurality of coils; and

a controller configured to drive the plurality of coils in a multi-phase arrangement so that at least one coil is driven while at least one other coil is used to sense a position of the field member.

2. The electronic device of claim 1 wherein the controller comprises a closed-loop controller.

3. The electronic device of claim 2 wherein the controller is configured to sense the position of the field member based upon a voltage associated with the at least one other coil.

4. The electronic device of claim 2 wherein the controller is configured to sense the position of the field member based upon a current associated with the at least one other coil.

5. The electronic device of claim 2 wherein the controller is configured to sense the position of the field member based upon a back electromotive force (EMF) from each of the plurality of coils.

6. The electronic device of claim 5 wherein the controller is configured to estimate a velocity of the field member based upon the back EMF from each of the plurality of coils.

7. The electronic device of claim 1 wherein the controller is configured to estimate a velocity of the field member based upon each of the plurality of coils.

8. The electronic device of claim 1 wherein the at least one permanent magnet comprises a plurality of permanent magnets.

9. The electronic device of claim 1 wherein the at least one permanent magnet comprises at least one cylindrical permanent magnet.

10. The electronic device of claim 1 wherein the linear haptic actuator comprises a ferritic core carrying the plurality of coils and having an opening therein through which the at least one permanent magnet passes.

11. The electronic device of claim 1 wherein the linear haptic actuator is configured to move along an x-axis, and wherein the plurality of coils are aligned along the x-axis.

12. An electronic device comprising:

a linear haptic actuator comprising

a housing,

a plurality of coils carried by the housing, and

a field member linearly movable within the housing and comprising a plurality of permanent magnets cooperating with the plurality of coils; and

a closed-loop controller configured to drive the plurality of coils in a multi-phase arrangement so that at least one coil is driven while at least one other coil is used to sense a position of the field member.

13. The electronic device of claim 12 wherein the closed-loop controller is configured to sense the position of the field member based upon a voltage associated with the at least one other coil.

14. The electronic device of claim 12 wherein the closed-loop controller is configured to sense the position of the field member based upon a current associated with the at least one other coil.

15. The electronic device of claim 12 wherein the plurality of permanent magnets comprises a plurality of cylindrical permanent magnets.

16. The electronic device of claim 12 wherein the linear haptic actuator comprises a ferritic core carrying the plurality of coils and having an opening therein through which the plurality of permanent magnet passes.

17. The electronic device of claim 12 wherein the linear haptic actuator is configured to move along an x-axis, and wherein the plurality of coils are aligned along the x-axis.

18. A method of driving a linear haptic actuator comprising a housing, a plurality of coils carried by the housing, and a field member linearly movable within the housing and comprising at least one permanent magnet cooperating with the plurality of coils, the method comprising:

using a controller coupled to the linear haptic actuator to drive the plurality of coils in a multi-phase arrangement so that at least one coil is driven while at least one other coil is used to sense a position of the field member.

19. The method of claim 18 wherein using the controller comprises using a closed-loop controller.

20. The method of claim 19 wherein the closed-loop controller is used to sense the position of the field member based upon a voltage associated with the at least one other coil.

21. The method of claim 19 wherein the closed-loop controller is used to sense the position of the field member based upon a current associated with the at least one other coil.

22. The method of claim 18 wherein the at least one permanent magnet comprises a plurality of permanent magnets.

23. The method of claim 18 wherein the linear haptic actuator is configured to move along an x-axis, and wherein the plurality of coils are aligned along the x-axis.