External Charger for an Implantable Medical Device Having a Thermal Diffuser

• US 20180345025A1
• Filed: 03/28/2018
• Published: 12/06/2018
• Est. Priority Date: 06/02/2017
• Status: Active Grant

• Current Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Neuromodulation Corporation (Boston Scientific Corporation)
• Inventors: Stinauer, Robert J., Chen, Joey
• Granted Patent: US 10,888,706 B2
• Time in Patent Office: Days
• 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
• CPC Class Codes: H01F 27/2876 Cooling cooling transformers and inductances in general H01F27/08
• 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 2310/23 The load being a medical device, a medical implant, or a life supporting device
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/007192 in response to temperature
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 1/181 associated with surface mounted components
• CPC Class Codes: H05K 2201/1003 Non-printed inductor
• CPC Class Codes: H05K 2201/10151 Sensor
• CPC Class Codes: H05K 7/1427 Housings

Abstract

An external charging system for an Implantable Medical Device (IMD) is disclosed having a thermal diffuser proximate to the primary charging coil for distributing heat from the primary charging coil. In an example, the primary charging coil is mounted to a first side of a circuit board, and the thermal diffuser is also connected to the first side and in contact with the primary charging coil. In one example, the thermal diffuser is a plastic material, such as an acrylic pad, with a high thermal conductivity and a low electrical conductivity. The thermal diffuser may also contact temperature sensors mounted to the first side of the circuit board.

Claims

1. An external charger system for an implantable medical device, the external charger system comprising:

a circuit board;

a primary charging coil mounted to a first side of the circuit board, wherein the primary charging coil, when energized, is configured to generate a magnetic field to be received at the implantable medical device; and

a thermal diffuser in contact with the first side of the circuit board and within the primary charging coil, wherein the thermal diffuser is configured to conduct heat away from the primary charging coil.

2. The external charger system of claim 1, wherein the thermal diffuser is further in contact with at least a portion of the primary charging coil.

3. The external charger system of claim 2, wherein the primary coil has an inner edge, and wherein the thermal diffuser has an outer edge in contact with the inner edge.

4. The external charger system of claim 1, further comprising a thermally insulating material in contact with a second side of the circuit board.

5. The external charger system of claim 1, further comprising at least one temperature sensor mounted to the circuit board.

6. The external charger system of claim 5, wherein the thermal diffuser is in contact with at least one of the temperature sensors.

7. The external charger system of claim 1, further comprising a first housing, wherein the circuit board, the primary charging coil, and the thermal diffuser are within the first housing.

8. The external charger system of claim 7, further comprising a second housing coupled to the first housing by a cable, wherein the second housing comprises charging circuitry configured to energize the primary charging coil via the cable to generate the magnetic field.

9. The external charger system of claim 8, further comprising at least one temperature sensor mounted to the circuit board, wherein each temperature sensor is configured to provide, via the cable, temperature data to control circuitry in the second housing, wherein the control circuitry is configured to use the temperature data to control generation of the magnetic field.

10. The external charger system of claim 9, wherein the control circuit is programmed with a maximum temperature, and wherein the control circuitry controls generation of the magnetic field so as to keep the temperature data from exceeding the maximum temperature.

11. The external charger system of claim 8, further comprising a user interface associated with the second housing, wherein no user interface elements are associated with the first housing.

12. The external charger system of claim 1, wherein the thermal diffuser comprises a plastic material.

13. The external charger system of claim 12, wherein the thermal diffuser comprises an acrylic material.

14. The external charger system of claim 1, further comprising at least one sense coil within and concentric with the primary charging coil, wherein a signal induced in each sense coil is configured to provide information relevant to alignment of the primary charging coil with the implantable medical device during generation of the magnetic field.

15. An external charger system for an implantable medical device, the external charger system comprising:

a first housing, in which comprises;

a circuit board;

a primary charging coil mounted to the circuit board, wherein the primary charging coil, when energized, is configured to generate a magnetic field to be received at the implantable medical device;

at least one temperature sensor mounted to the circuit board and each configured to provide temperature data; and

a thermal diffuser in contact with the primary charging coil and the at least one temperature sensor.

16. The external charger system of claim 15, wherein the primary charging coil and at least one of the temperature sensors are mounted to a first side of the circuit board, and wherein the thermal diffuser is further in contact with the first side of the circuit board.

17. The external charger system of claim 15, further comprising a thermally insulating material between a second side of the circuit board and the first housing.

18. The external charger system of claim 15, further comprising a second housing coupled to the first housing by a cable, wherein the second housing comprises charging circuitry configured to energize the primary charging coil via the cable to generate the magnetic field, wherein the second housing further comprises control circuitry, wherein the control circuitry is configured to receive, via the cable, the temperature data and to control generation of the magnetic field using the temperature data.

19. The external charger system of claim 15, wherein the thermal diffuser comprises a plastic material.

20. The external charger system of claim 19, wherein the thermal diffuser comprises an acrylic material.