COIL AND METHOD FOR INCREASING THE DEGREE OF AN ELECTROMAGNETIC COUPLING

• US 20170287630A1
• Filed: 03/29/2016
• Published: 10/05/2017
• Est. Priority Date: 03/29/2016
• Status: Active Grant

• Current Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Original Assignee: Motorola Mobility LLC (Lenovo Group Ltd.)
• Inventors: Pais, Martin R, Winkler, David A
• Granted Patent: US 10,026,547 B2
• Time in Patent Office: Days
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 2017/0066 with a magnetic layer
• CPC Class Codes: H01F 2017/0073 with a special conductive pattern, e.g. flat spiral
• CPC Class Codes: H01F 2038/143 for signals
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 29/10 having movable part of magnetic circuit high leakage transformers H01F38/08; dynamo-electric machines with movable part of magnetic circuit H02K23/44, H02K23/48
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

The present application provides a coil for facilitating an electromagnetic coupling and method for increasing the degree of an electromagnetic coupling. The coil for facilitating an electromagnetic coupling includes one or more loops formed from a material through which an electric current can flow. At least one of the one or more loops is adjustable, including at least one of a size and a shape of the at least one of the one or more loops of the coil being selectively adjustable.

Claims

1. A coil for facilitating an electromagnetic coupling, said coil comprising:

one or more loops formed from a material through which an electric current can flow, wherein at least one of the one or more loops is adjustable including at least one of a size and a shape of the at least one of the one or more loops of the coil being selectively adjustable.

2. A coil in accordance with claim 1, wherein the coil is coupled to a substrate at one or more points along a length of the coil, and the coil includes one or more sections forming one or more loops that are not coupled to the substrate.

3. A coil in accordance with claim 1, wherein the one or more loops are arranged to form a plurality of concentric loops, wherein each respective end of each of the one or more loops is coupled to a respective one of a preceding loop and a subsequent loop from the one or more loops, with the exception of an innermost loop and an outermost loop, which are each coupled to another loop from the one or more loops at only one end.

4. A coil in accordance with claim 1, wherein the coil further comprises a mechanical adjustor for applying a force to the coil at at least one point along the length of the coil.

5. A coil in accordance with claim 4, wherein the mechanical adjustor includes a motor which is adapted for applying a rotational force to an end of the coil.

6. A coil in accordance with claim 5, wherein the motor applies a rotational force to an end of an innermost loop in a coil including one or more concentric loops.

7. A coil in accordance with claim 4, wherein the mechanical adjustor applies an inward force to one or more points along an outer circumference of the coil, wherein the shape of the coil is deflected inward proximate each of the points the force is applied.

8. A coil in accordance with claim 7, wherein the mechanical adjustor applying the inward force includes one or more linear actuators.

9. A coil in accordance with claim 7, wherein the inward deflection of the shape of the coil proximate each of the points the force is applied causes the shape of the coil to form one or more subloops.

10. A coil in accordance with claim 1, wherein the coil is located in a void.

11. A coil in accordance with claim 10, wherein the void has an outer circumference which is substantially circular, which restricts an ability of an outermost loop of the coil to expand.

12. A coil in accordance with claim 10, wherein a base of the void upon which the coil is adapted to rest curves upward further out from a center of the void, wherein as the loops of the coil expand the expanding portions of the coil are redirected by the base of the void in an upward direction.

13. A coil in accordance with claim 1, wherein the coil is part of a coil assembly, and the material through which an electric current can flow, is at least partially encased in a low electrically conductive material.

14. A coil in accordance with claim 1, wherein the coil is part of a coil assembly, and the material through which an electric current can flow, is at least partially encased in a low friction material.

15. A coil in accordance with claim 1, wherein at least one or more portions of the coil is formed from a shape-memory material, which is adapted to change shape based upon an externally applied stimulus being applied to the respective portions of the coil.

16. A coil in accordance with claim 15, wherein the externally applied stimulus includes a change in temperature.

17. A coil in accordance with claim 1, which is incorporated as part of a wireless charging device.

18. A method for increasing the degree of an electromagnetic coupling where the electromagnetic coupling includes a coupling between at least a pair of distinct coils where at least one of the electromagnetically coupled coils has at least one loop adjustable in at least one of size and shape, the method comprising:

determining an efficiency of the coil having the at least one adjustable loop in transferring power as part of an electromagnetic coupling by comparing a measured amount of power transmitted in a first coil of the at least a pair of distinct coils with a measured amount of power received in a second coil of the at least a pair of distinct coils;

adjusting at least one of size and shape of the at least one adjustable loop of the coil;

determining a new efficiency of the coil in transferring power as part of an electromagnetic coupling after the at least one of size and shape of the at least one adjustable loop has been adjusted;

comparing the new efficiency with the efficiency determined immediately prior to the most recent adjustment; and

retaining the adjustment in the at least one of size and shape of the at least one adjustable loop, when the new efficiency is determined to be an improvement relative to the efficiency determined immediately prior to the most recent adjustment, or otherwise reverting back to the size and shape of the at least one adjustable loop of the coil prior to adjustment, when the new efficiency is determined to not be an improvement relative to the efficiency determined immediately prior to the most recent adjustment.

19. A method in accordance with claim 18 further comprising:

repeating the steps of adjusting, determining, comparing, and retaining/reverting wherein the adjustment includes a further similar type of adjustment, until the most recent determination and comparison in response to the most recent adjustment stops resulting in an improved efficiency relative to the most recent determined efficiency associated with the electromagnetic coupling immediately prior to the most recent adjustment.

20. A method in accordance with claim 18 further comprising:

repeating the steps of adjusting, determining, comparing, and retaining/reverting, wherein the adjustment includes a different type of adjustment, when the new determined efficiency after the immediately prior adjustment fails to result in an improved efficiency relative to the most recent determined efficiency associated with the electromagnetic coupling immediately prior to the most recent adjustment.