Patent Application
20200009393
Implantable medical devices (e.g., cochlear implants, retinal implants, cardiac pacemakers, implantable defibrillators, recording devices, neurostimulators, etc.) often communicate with and/or receive power from an external device by way of a transcutaneous inductive link. To this end, an implantable medical device may include or be connected to an implantable antenna, which may form an inductive link with an external antenna that is connected to the external device.
During manufacturing of a conventional implantable medical device, conductive wires of an implantable antenna may be terminated in a manner that allows the wires to be conductively connected to a feedthrough electrical contact of a circuit included in the implantable medical device. To this end, distal ends of the conductive wires are conventionally placed within a tube, which is then crimped in order to hold the conductive wires in place. The tube is then conductively affixed to the feedthrough electrical contact. Unfortunately, this approach requires custom tooling and unique machined components. Moreover, it is difficult to manually hold the conductive wires in place while the tube is crimped. This results in manufacturing processes for implantable medical devices that can be relatively expensive, time consuming, and resource intensive.
The accompanying drawings illustrate various embodiments and are a part of the specification. The illustrated embodiments are merely examples and do not limit the scope of the disclosure. Throughout the drawings, identical or similar reference numbers designate identical or similar elements.
Antenna wire termination assemblies for use in implantable medical devices are described herein. For example, an exemplary antenna wire termination assembly (“termination assembly”) includes a helically shaped conductive retention coil and a conductive tab member. The retention coil has a first end and a second end that define a length of the retention coil, a plurality of turns between the first and second ends, and a flat side along the length of the retention coil. The flat side is formed by a plurality of aligned straight segments included in the turns. The conductive tab member has a proximal portion conductively affixed to the flat side of the retention coil and a distal portion extending away from the second end of the retention coil in a direction that is parallel with the length of the retention coil.
The termination assembly is configured to terminate a plurality of conductive wires of an antenna and conductively connect the wires to a feedthrough electrical contact of a circuit included in an implantable medical device. For example, end portions of the conductive wires may be positioned between the turns of the retention coil. The turns are configured to retain the end portions of the conductive wires. For example, a natural compressive force of the retention coil may be configured to retain the end portions of the conductive wires within the turns of the retention coil. Additionally or alternatively, the retention coil may be compressed by an external force (e.g., manually or by a machine) to retain the end portions of the conductive wires within the turns of the retention coil.
While the conductive wires are retained within the turns of the retention coil, the conductive wires are conductively affixed (e.g., welded) to the retention coil. This conductively couples the conductive wires to one another, to the retention coil, and to the conductive tab member. The distal portion of the tab member is conductively affixed (e.g., welded) to the feedthrough electrical contact of the circuit in the implantable medical device. In this manner, the conductive wires are conductively connected to the circuit. In instances where both ends of the conductive wires have to be terminated (e.g., for loop antennas, etc.), two termination assemblies as described herein may be used.
Various benefits are associated with the termination assemblies described herein. For example, the termination assemblies described herein obviate the need to crimp or weld a tube onto the ends of the conductive wires of an antenna, which obviates the need for custom tooling and/or machined components during manufacturing. Moreover, the termination assemblies described herein are self fixturing in that they hold the conductive wires of the antenna in place in between the turns of the termination assemblies even before the conductive wires are welded or otherwise affixed to the termination assemblies. This allows a user to more easily handle and assemble an implantable medical device during manufacturing. The termination assemblies described herein also provide strain relief and support for the conductive wires during testing that occurs during manufacturing and during normal use of the implantable medical device by a user. These and other benefits of the termination assemblies described herein will be made apparent in the description that follows.
Antennas 106 and 108 may form an inductive link 110 when in close proximity one to another. Signals (e.g., power and/or data) may be transmitted by external device 104 to implantable medical device 102 by way of inductive link 110. Signals (e.g., back telemetry signals) may additionally or alternatively be transmitted by implantable medical device 102 to external device 104 by way of inductive link 110.
Implantable medical device 102 and external device 104 may be implemented by any suitable combination of devices. For example, implantable medical device 102 may be implemented by a cochlear implant included in a cochlear implant system and external device 104 may be implemented by a sound processor included in the cochlear implant system. Implantable medical device 102 may alternatively be implemented by a retinal implant, a cardiac pacemaker, an implantable defibrillator, a recording device, a neurostimulator, and/or any other implantable medical device. External device 104 may alternatively be implemented by a remote control device, a mobile device (e.g., a mobile phone), a desktop computer, and/or any other computing or processing device configured to communicate with (e.g., control) implantable medical device 102.
Although four wires 302 are shown in
Retention coil 402 and tab member 404 may each be made out of any suitable conductive material (e.g., a conductive metal). As will be described below, while
Retention coil 402 further includes a plurality of turns 504 (e.g., turns 504-1 through 504-7) between ends 502. Turns 504 may be formed by round wire, as shown in
As will be described below, turns 504 are configured to retain end portions of a plurality of conductive wires of an antenna that are positioned between 504. To this end, as labeled in
As shown, each turn 504 includes a plurality of straight segments. For example, turn 504-7 includes straight segments 508-1 through 508-4. In the particular example of
As shown, because retention coil 402 is square shaped, retention coil 402 has four flat sides each formed by a plurality of aligned straight segments included in turns 504. For example, a dashed box shown in
As shown, distal portion 408 includes a conductive receptacle 602. Conductive receptacle 602 is positioned to align with and couple to a feedthrough electrical contact (e.g. a feedthrough pin) of a circuit of the implantable medical device when termination assembly 400 is placed within a can of the implantable medical device. Tab member 404 may be configured to conductively connect to the circuit in any other suitable manner.
As also shown, proximal portion 406 also includes a conductive receptacle 604. Conductive receptacle 604 is configured to facilitate affixation (e.g., welding) of tab member 404 to top flat side 510 of retention coil 402. In some alternative embodiments, conductive receptacle 604 is not included on tab member 404.
In step 702, end portions of a plurality of conductive wires included in an antenna are positioned between turns 504 of termination assembly 402. For example,
End portions of wires 802 may be positioned between turns 504 of termination assembly 402 in any suitable manner. For example, a person may manually position wires 802 between turns 504 of termination assembly 402. In some examples, the person may manually separate turns 504 (e.g., by pulling turns 504 apart) in order to fit wires 802 therebetween. Alternatively, the spacing between turns 504 may be such that wires 802 may be readily positioned between turns 504 without requiring manual separation of turns 502. In some alternative embodiments, a tool or machine is used to position wires 802 between turns 504.
In step 704, retention coil 402 is compressed. For example, compressive force may be applied in the direction of arrows 804-1 and 804-2 to compress retention coil 402. This compression may retain wires 802 between turns 504. The compression of retention coil 402 may be performed manually (e.g., by a person squeezing the two ends of retention coil 402 towards each other) and/or with a tool or machine.
In some alternative embodiments, step 704 is omitted (i.e., not performed). For example, if retention coil 402 sufficiently retains wires 802 between turns 504, it may not be necessary to compress retention coil 402.
In step 706, the end portions of wires 802 are conductively affixed to retention coil 402. For example, once wires 802 have been positioned between turns 504, wires 802 may be welded (e.g., resistance welded or laser welded), soldered, bonded with conductive epoxy, or otherwise conductively coupled to retention coil 402 (i.e., between turns 504). In this manner, wires 802 may be even more securely connected to retention coil 402.
In step 708, retention coil 402 is positioned inside a can of an implantable medical device. To illustrate,
In step 710, proximal portion 406 of tab member 404 is affixed to the top flat side of retention coil 402. This is shown in
In step 712, tab member 404 is connected to a feedthrough electrical contact included in can 902. For example, with reference to
In the preceding description, various exemplary embodiments have been described with reference to the accompanying drawings. It will, however, be evident that various modifications and changes may be made thereto, and additional embodiments may be implemented, without departing from the scope of the invention as set forth in the claims that follow. For example, certain features of one embodiment described herein may be combined with or substituted for features of another embodiment described herein. The description and drawings are accordingly to be regarded in an illustrative rather than a restrictive sense.
