Method of Energy Transfer to an Implantable Medical Device While Coupling Energy to Charging Unit

Abstract

External power source, charger, system and method for an implantable medical device having therapeutic componentry and a secondary coil operatively coupled to the therapeutic componentry. A primary charging coil is capable of transcutaneously inductively energizing the secondary coil when externally placed in proximity of the secondary coil. Drive circuitry is operatively coupled to the primary charging coil for exciting the primary charging coil. A rechargeable power source is operatively coupled to the drive circuitry. A secondary recharging coil is operatively coupled to the rechargeable power source. A primary recharging coil is adapted to be coupled to a source of AC power which when placed in proximity of the secondary recharging coil can inductively energize the secondary recharging coil in order to charge the rechargeable power source.

Description

RELATED APPLICATION [0001] This application is a continuation of U.S. patent application Ser. No. 10 / 836,318, filed Apr. 30, 2004 and claims priority therefrom.FIELD OF THE INVENTION [0002] This invention relates to implantable medical devices and, in particular, to energy transfer devices, systems and methods for implantable medical devices. BACKGROUND OF THE INVENTION [0003] Implantable medical devices for producing a therapeutic result in a patient are well known. Examples of such implantable medical devices include implantable drug infusion pumps, implantable neurostimulators, implantable cardioverters, implantable cardiac pacemakers, implantable defibrillators and cochlear implants. Of course, it is recognized that other implantable medical devices are envisioned which utilize energy delivered or transferred from an external device. [0004] A common element in all of these implantable medical devices is the need for electrical power in the implanted medical device. The implanted...

AI Technical Summary

Benefits of technology

[0019] An external power source for transcutaneously transferring energy to an implantable medical device must obtain power from a source. The external source of power is typically either from batteries carried within the external power source or directly from readily available AC power, for example, from a standard wall socket. Obtaining power from batteries carried within the external power source is convenient and may allow the patient to be at least somewhat mobile, the amount of power available is limited by the size and weight of the batteries before the batteries are exhausted. However, obtaining power directly from standard readily available AC power not only limits the patient's mobility but also poses a potentially serious health risk. Placing a primary inductive charging coil directly on the patient's skin while the external power source is connected directly to standard AC power risks shock to the patient in the event of a malfunction of the external power source.

[0020] In one embodiment, the present invention provides an external power source for an implantable medical device having therapeutic componentry and a secondary coil operatively coupled to the therapeutic componentry. A primary charging coil is capable of transcutaneously inductively energizing the secondary coil when externally placed in proximity of the secondary coil. Drive circuitry is operatively coupled to the primary charging coil for exciting the primary charging coil. A rechargeable power source is operatively coupled to the drive circuitry. A secondary recharging coil is operatively coupled to the rechargeable power source. A primary recharging coil is adapted to be coupled to a source of AC power which when placed in proximity of the secondary recharging coil can inductively energize the secondary recharging coil in order to charge the rechargeable power source.

[0021] Utilizing a second inductive charging system, the second one for charging batteries in the external power supply, allows the patient to be mobile when the batteries are sufficient to transfer energy to the implantable medical device and allows the patient to be safely coupled to a source of standard AC power without fear of shock or electrocution if the batteries need to be refreshed.

[0022] In another embodiment, the present invention provides a charger for an implantable medical device having an internal rechargeable power source, therapeutic componentry operatively coupled to the internal rechargeable power source. A secondary coil is operatively coupled to the therapeutic componentry and an internal telemetry coil. A primary charging coil is capable of inductively energizing the secondary coil for charging the internal rechargeable power source when externally placed in proximity of the secondary coil. Drive circuitry is operatively coupled to the primary charging coil for exciting the primary charging coil. A rechargeable power source is operatively coupled to the drive circuitry. A secondary recharging coil is operatively coupled to the rechargeable power source. A primary recharging coil is adapted to be coupled to a source of AC power which when placed in proximity of the secondary recharging coil can inductively energize the secondary recharging coil in order to charge the rechargeable power source.

[0023] In another embodiment, the present invention provides a system for transcutaneous energy transfer. An implantable medical device has therapeutic componentry for producing a therapeutic output and a secondary coil operatively coupled to the therapeutic componentry. An external power source has a primary charging coil capable of inductively energizing the secondary coil when externally placed in proximity of the secondary coil. Drive circuitry is operatively coupled to the primary charging coil for exciting the primary charging coil. A rechargeable power source is operatively coupled to the drive circuitry. A secondary recharging coil is operatively coupled to the rechargeable power source. A primary recharging coil is adapted to be coupled to a source of AC power which when placed in proximity of the secondary recharging coil can inductively energize the secondary recharging coil in order to charge the rechargeable power source.

Problems solved by technology

However, obtaining power directly from standard readily available AC power not only limits the patient's mobility but also poses a potentially serious health risk.

Placing a primary inductive charging coil directly on the patient's skin while the external power source is connected directly to standard AC power risks shock to the patient in the event of a malfunction of the external power source.

Images