# US 2022/0032011 A1 · Microminiature EM Coil Sensor Pull Ring For Catheter > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0032011 A1 - Document ID: US20220032011A1 - Status: Published application - Kind: A1 - Application number: 17/388,119 - Filed: 2021-07-29 - Published: 2022-02-03 - Earliest claimed: 2020-07-29 - Assignees: IntriCon Corporation - Applicants: IntriCon Corporation - Inventors: Daniel J. Potter; Alexander L. Darbut; David Bosch; Sam A. Puent - Web page: https://patentgrep.com/patent/US20220032011A1 ## CPC - A61M 25/0158: {with magnetic or electrical means, e.g. by using piezo materials, electroactive polymers, magnetic materials or by heating of shape memory materials} - A61M 25/0138: {having flexible regions as a result of weakened outer material, e.g. slots, slits, cuts, joints or coils} - A61M 25/0147: {with movable mechanical means, e.g. pull wires} - A61M 2025/015: {Details of the distal fixation of the movable mechanical means} - A61M 2025/0163: {Looped catheters} - A61M 2025/0166: {Sensors, electrodes or the like for guiding the catheter to a target zone, e.g. image guided or magnetically guided} - A61M 2205/0244: Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology - A61M 2205/0272: Electro-active or magneto-active materials - A61M 2205/3317: Electromagnetic, inductive or dielectric measuring means - A61M 2207/00: Methods of manufacture, assembly or production - A61M: DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY (introducing media into or onto the bodies of animals A61D7/00; means for inserting tampons A61F13/26; devices for administering food or medicines orally A61J; containers for collecting, storing or administering blood or medical fluids A61J1/05); DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY (surgery A61B; chemical aspects of surgical articles A61L); DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR {(Electrotherapy, e.g. producing anaesthesia by the use of alternating or intermittent currents A61N1/36021)} ## Abstract A microminiature electro-magnetic coil sensor pull ring with a pull wire attached thereto is used in changing the angle of a distal end of a medical catheter. The tubular pull ring has a connection recess with a flat bottom machined into the full wall thickness and located proximal to a coil wrap area. Circuit wires are electrically connected to the two lead ends of the coil within the connection recess, such that neither the circuit wires nor the lead ends stand proud of the full wall thickness. The coil wrap area is also recessed, and can have side walls defining an offset angle for the turns of the coil. In another aspect, a coil is wound around one of the pull wires for the pull ring. ## Claims ### Claim 1 A microminiature electro-magnetic coil sensor pull ring for use in a medical catheter, comprising: a tubular pull ring having a full wall thickness, the pull ring having a coil wrap area about a longitudinal axis, the pull ring having a connection recess into the full wall thickness and located proximal to the coil wrap area, the pull ring having at least one pull wire connection location into the full wall thickness and located proximal to the coil wrap area; a coil formed of a flexible, electrically insulated metal wire wrapped about the coil wrap area with a plurality of turns for sensing through human tissue, the wire being smaller than 40 AWG, the wire terminating in two lead ends extending flexibly from the turns; at least one pull wire connected to the pull ring within the pull wire connection location, for changing the angle of the pull ring for navigation of the medical catheter through human tissue; circuit wires electrically connected to the two lead ends within the connection recess, such that neither the circuit wires nor the lead ends stand proud of the full wall thickness. ### Claim 2 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, wherein the connection recess has a flat bottom surface. ### Claim 3 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, wherein the coil wrap area is recessed relative to the full wall thickness, with a proximal region of full wall thickness on the pull ring proximal to the coil wrap area and with a distal region of full wall thickness on the pull ring distal to the coil wrap area, such that the coil does not stand proud of the full wall thickness. ### Claim 4 (depends on 3) The microminiature electro-magnetic coil sensor pull ring of claim 3, wherein the connection recess extends from a proximal end of the pull ring to the coil wrap area. ### Claim 5 (depends on 3) The microminiature electro-magnetic coil sensor pull ring of claim 3, wherein the coil wrap area is defined by at least one side wall of the pull ring, the side wall defining a plane which has an offset angle relative to a plane normal to an axis of the pull ring, and wherein the turns of the coil wire are offset by the same offset angle. ### Claim 6 (depends on 5) The microminiature electro-magnetic coil sensor pull ring of claim 5, wherein a second coil wrap area is defined by a second side wall of the pull ring, with a second coil wrapped about the second coil wrap area with a plurality of turns for sensing through human tissue, wherein the second side wall has a second offset angle relative to a plane normal to an axis of the pull ring, and wherein the turns of the second coil wire are offset by the second offset angle, such that the turns of the second coil are not parallel to the turns of the coil. ### Claim 7 (depends on 5) The microminiature electro-magnetic coil sensor pull ring of claim 5, wherein the pull ring is formed of an austenitic stainless steel material. ### Claim 8 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, further comprising a second coil formed of a flexible, electrically insulated metal wire wrapped about the pull wire with a plurality of turns for sensing through human tissue, the wire being smaller than 40 AWG. ### Claim 9 (depends on 8) The microminiature electro-magnetic coil sensor pull ring of claim 8, where the pull ring has a second connection recess into the full wall thickness and located proximal to the coil wrap area, for connecting circuit wires to leads for the second coil. ### Claim 10 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, wherein the pull ring is formed of a 400-series ferritic stainless steel material. ### Claim 11 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, wherein the circuit wires are with a range from 32 to 46 AWG, provided as a twisted pair within a sheath. ### Claim 12 (depends on 1) The microminiature electro-magnetic coil sensor pull ring of claim 1, wherein the coil is wound with 100 to 10000 turns in 5 to 20 layers. ### Claim 13 A method of manufacturing a microminiature electro-magnetic coil sensor pull ring for use in a medical catheter, comprising: forming a tubular pull ring, the tubular pull ring having a full wall thickness about a longitudinal axis; machining a coil wrap area by removing material from an outer side of the full wall thickness; machining an electrical connection recess into the full wall thickness and located proximal to the coil wrap area; machining at least one pull wire connection location into the full wall thickness and located proximal to the coil wrap area; winding a coil about the coil wrap area, the coil being formed of a flexible, electrically insulated metal wire with a plurality of turns for sensing through human tissue, the wire being smaller than 40 AWG, the wire terminating in two lead ends extending flexibly from the turns; attaching at least one pull wire to the pull ring within the pull wire connection location, the pull wire being adapted for changing the angle of the pull ring for navigation of the medical catheter through human tissue; and electrically connecting circuit wires to the two lead ends within the connection recess, such that neither the circuit wires nor the lead ends stand proud of the full wall thickness. ### Claim 14 (depends on 13) The method of claim 13, wherein the electrical connection recess is machined to provide a flat bottom surface. ### Claim 15 (depends on 13) The method of claim 13, wherein the coil wrap area is machined between a proximal region of full wall thickness on the pull ring proximal to the coil wrap area and a distal region of full wall thickness on the pull ring distal to the coil wrap area, wherein the coil is wound such that the coil does not stand proud of the full wall thickness, and wherein the connection recess is machined to extend from a proximal end of the pull ring to the coil wrap area. ### Claim 16 (depends on 13) The method of claim 13, wherein the pull wire has a circular cross-section, and further comprising: stamping a distal end of the circular cross-sectioned pull wire into a rectangular cross-section prior to the attaching act. ### Claim 17 A microminiature electro-magnetic coil sensor pull ring for use in a medical catheter, comprising: a tubular pull ring having at least one pull wire connection location; at least one pull wire connected to the pull ring at the pull wire connection location, for changing the angle of the pull ring for navigation of the medical catheter through human tissue; a coil formed of a flexible, electrically insulated metal wire wrapped about the pull wire with a plurality of turns for sensing through human tissue, the wire being smaller than 40 AWG. ### Claim 18 (depends on 17) The microminiature electro-magnetic coil sensor pull ring of claim 17, wherein the coil wire terminates in two lead ends extending flexibly from the turns; wherein the pull ring has a connection recess relative to a full wall thickness of the tubular pull ring, and further comprising: circuit wires electrically connected to the two lead ends within the connection recess, such that neither the circuit wires nor the lead ends stand proud of the full wall thickness. ### Claim 19 (depends on 18) The microminiature electro-magnetic coil sensor pull ring of claim 18, wherein the pull ring has a coil wrap area recessed relative to the full wall thickness, with a proximal region of full wall thickness on the pull ring proximal to the coil wrap area and with a distal region of full wall thickness on the pull ring distal to the coil wrap area, and further comprising: a second coil wound about the coil wrap area of the pull ring. ### Claim 20 (depends on 19) The microminiature electro-magnetic coil sensor pull ring of claim 19, wherein the second coil does not stand proud of the full wall thickness.