HIGH EFFICIENCY MAGNETIC LINK FOR IMPLANTABLE DEVICES

• US 20150028798A1
• Filed: 07/29/2014
• Published: 01/29/2015
• Est. Priority Date: 07/29/2013
• Status: Active Grant

• Current Assignee: Alfred E. Mann Foundation For Scientific Research
• Original Assignee: Alfred E. Mann Foundation For Scientific Research
• Inventors: Dearden, Brian R., Griffith, Glen A.
• Granted Patent: US 9,855,436 B2
• Time in Patent Office: Days
• US Class Current: 320/107
• CPC Class Codes: A61N 1/36125 Details of circuitry or electric components
• CPC Class Codes: A61N 1/3787 from an external energy source
• CPC Class Codes: H02J 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0042 characterised by the mechanical construction

Abstract

Systems and devices for a high-efficiency magnetic link for implantable devices are disclosed herein. These devices can include a charging coil located in the implantable device and a charging coil located in a charge head of a charger. The charging coils can each include an elongate core and wire windings wrapped around a longitudinal axis of the elongate core. The charging coil of the charge head can be attached to a rotatable mount, which can be used to align the longitudinal axis of the charging coil of the charge head with longitudinal axis of the implantable device such that the axes of the charging coils are parallel.

Claims

1. A method of charging an implantable device, the method comprising:

positioning a charging head comprising a transmitting coil attached to a rotatable mount proximate to an implantable device comprising a receiving coil;

determining a first orientation of the transmitting coil with respect to the receiving coil; and

rotating the rotatable mount and the thereto attached transmitting coil until the transmitting coil has a second orientation with respect to the receiving coil.

2. The method of claim 1, wherein the transmitting coil has a longitudinal axis and at least one wire wrapped around the longitudinal axis.

3. The method of claim 2, wherein the receiving coil has a longitudinal axis and at least one wire wrapped around the longitudinal axis.

4. The method of claim 3, wherein determining the first orientation of the transmitting coil with respect to the receiving coil comprises determining an angle between the longitudinal axis of the transmitting coil with respect to the longitudinal axis of the receiving coil.

5. The method of claim 4, wherein the angle between the longitudinal axis of the transmitting coil is non-parallel with the longitudinal axis of the receiving coil in the first orientation.

6. The method of claim 4, wherein an angle between the longitudinal axis of the transmitting coil and the longitudinal axis of the receiving coil in the second orientation is less than the angle between the longitudinal axis of the transmitting coil and the longitudinal axis of the receiving coil in the first orientation, and wherein the charging efficiency in the first orientation is less than the charging efficiency in the second orientation.

7. The method of claim 3, wherein rotating the rotatable mount and the thereto attached transmitting coil until the transmitting coil has a second orientation with respect to the receiving coil comprises determining when an angle between the longitudinal axis of the transmitting coil and the longitudinal axis of the charging coil is minimized.

8. The method of claim 7, wherein the second orientation is reached when the angle between the longitudinal axis of the transmitting coil and the longitudinal axis of the charging coil is minimized.

9. An implantable device comprising:

a processor configured to control the operation of the implantable device and to generate a plurality of electrical impulses for stimulating a peripheral nerve;

a lead configured for placement proximate to a peripheral nerve;

an energy storage device configured to store energy; and

a charging coil comprising;

an elongate core having a first end, and second end, and a longitudinal axis extending therebetween; and

a wire wrapped in a plurality of coils around the elongate core and the longitudinal axis of the elongate core.

10. The implantable device of claim 9, wherein the wire comprises litz wire.

11. The implantable device of claim 9, wherein the elongate core comprises a soft ferrite material.

12. The implantable device of claim 9, wherein the charging coil has a Q factor of at least 70.

13. The implantable device of claim 9, wherein the charging coil has a Q factor of at least 80.

14. The implantable device of claim 9, wherein the charging coil further comprises a capacitor electrically connected to the wire.

15. The implantable device of 14, wherein the capacitor comprises a high Q COG capacitor.

16. The implantable device of 14, wherein the capacitor is located on the charging coil.

17. The implantable device of 14, wherein the capacitor is located proximate to the charging coil.

18. The implantable device of 14, wherein the capacitor is positioned so as to create a high Q tank circuit.

19. A charging head comprising:

a contact surface;

a rotatable mount positioned a distance from the contact surface and rotatable with respect to the contact surface; and

a charging coil attached to the rotatable mount.

20. The charging head of claim 19, wherein the charging coil comprises:

an elongate core having a first end, and a second end, and a longitudinal axis extending therebetween; and

a wire wrapped in a plurality of coils around the elongate core and the longitudinal axis of the elongate core.

21. The charging head of claim 20, wherein the elongate core comprises a first foot located at the first end and a second foot located at the second end.

22. The charging head of claim 21, wherein the first and second feet extend towards the contact surface.

23. The charging head of claim 22, wherein the contact surface comprises a track configured to receive the first and second feet and to allow the rotation of the rotatable mount and the thereto attached charging coil.

24. The charging head of claim 23, wherein the charging coil can rotate at least 180 degrees.

25. The charging head of claim 19, wherein the wire comprises litz wire.

26. The charging head of claim 19, wherein the elongate core comprises a soft ferrite material.

27. The charging head of claim 19, wherein the charging coil has a Q factor of at least 50.

28. The charging head of claim 19, wherein the charging coil has a Q factor of at least 100.

29. A charging system comprising:

an implantable device comprising;

a receiving coil having;

an elongate core having a first end, a second end, and a longitudinal axis extending therebetween; and

a wire wrapped in a plurality of coils around the elongate core and the longitudinal axis of the elongate core; and

a charging head comprising;

a transmitting coil having;

an elongate core having a first end, a second end, and a longitudinal axis extending therebetween; and

a wire wrapped in a plurality of coils around the elongate core and the longitudinal axis of the elongate core.

30. The charging system of claim 29, wherein the receiving coil comprises a capacitor electrically connected to the wire of the receiving coil.

31. The charging system of claim 29, wherein the charging head comprises a rotatable mount.

32. The charging system of claim 31, wherein the transmitting coil is attached to the rotatable mount.

33. The charging system of claim 32, wherein the rotatable mount is rotatable between a first position and a second position.

34. The charging system of claim 33, wherein the rotatable mount is lockable in the first position and in the second position.

35. The charging system of claim 32, further comprising circuitry configured to detect an angular position of the receiving coil with respect to the transmitting coil.

36. The charging system of claim 35, wherein the circuitry configured to detect an angular position of the receiving coil with respect to the transmitting coil are in the charging head.

37. A method of charging an implantable device, the method comprising:

positioning an external charger on an outer surface of a person'"'"'s body proximate an implanted electrical pulse generator, the external charger including a housing and charging coil, the charging coil supported inside the housing such that the charging coil is rotatable inside of the housing, the implanted electrical pulse generator including a charging coil;

fixing the position of the external charger on the outer surface of the person'"'"'s body; and

while the external charger is fixed on the outer surface of the person'"'"'s body, rotating the charging coil of the external charger to change an orientation of the charging coil of the external charger relative to the charging coil of the implanted electrical pulse generator.

38. The method of claim 37, wherein the implanted electrical pulse generator further comprises at least one electrode implanted proximate a peripheral nerve of the person.