VARYING THE EFFECTIVE COIL AREA FOR AN INDUCTIVE TRANSCUTANEOUS POWER LINK

• US 20110009924A1
• Filed: 07/12/2010
• Published: 01/13/2011
• Est. Priority Date: 07/10/2009
• Status: Active Grant

• Current Assignee: Cochlear Limited
• Original Assignee: Cochlear Limited
• Inventors: Meskens, Werner
• Granted Patent: US 8,996,121 B2
• Time in Patent Office: Days
• US Class Current: 607/57
• CPC Class Codes: A61N 1/36038 Cochlear stimulation
• CPC Class Codes: A61N 1/37229 Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/3787 from an external energy source

Abstract

A prosthesis including an external device and an implantable component. The external device includes a first inductive communication component. The implantable component includes a second inductive communication component, wherein the implantable component is configured to be implanted under skin of a recipient. The external device is configured to transmit power via magnetic induction transcutaneously to the implantable component via the second inductive communication component. The internal component is configured to receive at least a portion of the power transmitted from the external device via the inductive communication component. At least one of the first and second inductive communication components comprise an inductive communication component configured to vary its effective coil area.

Claims

1. A prosthesis, comprising:

an external device including a first inductive communication component; and

an implantable component including a second inductive communication component, wherein the implantable component is configured to be implanted under skin of a recipient,

wherein the external device is configured to transmit power via magnetic induction transcutaneously to the implantable component via the first inductive communication component,

wherein the internal component is configured to receive at least a portion of the power transmitted from the external device via the second inductive communication component, and

wherein at least one of the first and second inductive communication components comprise an inductive communication component configured to vary its effective coil area.

2. The prosthesis of claim 1, wherein the inductive communication component configured to vary its effective coil area comprises:

a first inductance coil including at least a first looped wire; and

a second inductance coil including at least a second looped wire, wherein

the loop of the first looped wire encircles the center of the second looped wire, and

the first looped wire is electrically isolated from the second looped wire.

3. The prosthesis of claim 2, wherein the inductive communication component configured to vary its effective coil area includes a switch assembly that is configured to alternately place the first inductance coil and the second inductance coil into electrical communication with at least one of a supply of power and a load, thereby varying the effective coil area of the inductive communication component.

4. The prosthesis of claim 2, wherein the first inductance coil has a first effective coil area and the second inductance coil has a second effective coil area that is less than the first effective coil area.

5. The prosthesis of claim 4, wherein the ratio of the first effective coil area to the second effective coil area is about 2 to 1.

6. The prosthesis of claim 1, wherein the inductive communication component configured to vary its effective coil area comprises at least a first coil and a second coil having a different physical configuration than the first coil, wherein the first coil is electrically isolated from the second coil.

7. The prosthesis of claim 1, wherein the inductive communication component configured to vary its effective coil area is configured to vary the ratio of the effective coil area of the first inductive communication component to the effective coil area of the second inductive communication component.

8. The prosthesis of claim 1, wherein the inductive communication component configured to vary its effective coil area is configured to vary the coupling factor between the first inductive communication component and the second inductive communication component.

9. The prosthesis of claim 1, wherein the first inductive communication component is the inductive communication component configured to vary its effective coil area.

10. The prosthesis of claim 1, wherein the inductive communication component configured to vary its effective coil area comprises a looped wire, and wherein the inductive communication component configured to vary its effective coil area is configured to vary the area enclosed by the looped wire.

11. The prosthesis of claim 10, wherein the prosthesis is configured so that the looped wire may be fed in a first direction to expand the area enclosed by the looped wire and fed in an opposite direction from the first direction to reduce the area enclosed by the looped wire.

12. The prosthesis of claim 1, wherein the prosthesis is a cochlear implant, wherein the internal component is a receiver/stimulator of the cochlear implant.

13. A method of transcutaneously transmitting power from an external device to an implantable component of a prosthesis implanted in a recipient, comprising:

transmitting power during a first temporal period from the external device through skin of the recipient to the implantable component via an inductive communication component system;

varying, after the first temporal period, the coupling factor k of the inductive communication component system; and

transmitting, after the first temporal period and after varying the coupling factor k, power from the external device through skin of the recipient to the implantable component of the prosthesis via the inductive communication component system.

14. The method of claim 13, wherein the coupling factor k is varied by varying the ratio of an effective coil area of an external inductive communication component to an effective coil area of an implanted inductive communication component (A₁/A₂) of the system;

15. The method of claim 13, further comprising removing a first inductance coil exterior to the recipient from the inductance communication component system and replacing the first inductance coil with a second inductance coil having an effective coil area substantially different than that of the first inductance coil, thereby varying the coupling factor k of the system.

16. The method of claim 14, further comprising measuring a voltage of the implantable component before varying A₁/A₂, and automatically varying A₁/A₂ based on the measured voltage of the implantable component.

17. The method of claim 13, wherein A₁/A₂ is varied from a value of about 1 to a value of about 0.4 or less.

18. The method of claim 14, further comprising increasing a voltage of the implantable component by reducing the value of A₁/A₂.

19. A system for transcutaneously transmitting power from an external device to an implantable component of a prosthesis implanted in a recipient, comprising

an external device including an external inductive communication component;

and

an implantable component including an implanted inductive communication component, wherein

the effective coil area of the external inductive communication component is substantially different from the effective coil area of the implanted inductive communication component.

20. The system of claim 19, wherein the effective coil area of the external inductive communication component is about 40% or less than the effective coil area of the implanted inductive communication component.