# US 10,478,621 B1 · Retractable lead systems > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,478,621 B1 - Document ID: US10478621B1 - Status: Granted - Kind: B1 - Application number: 16/208,102 - Filed: 2018-12-03 - Granted: 2019-11-19 - Earliest claimed: 2018-12-03 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: David Allen Nelson; Mark Derakhshan - Web page: https://patentgrep.com/patent/US10478621B1 ## CPC - A61N 1/057: {Anchoring means; Means for fixing the head inside the heart} - H01H 33/66: Vacuum switches - A61N 1/3752: {Details of casing-lead connections} - G01R 33/28: Details of apparatus provided for in groups G01R33/44 - G01R33/64 - G01R 33/3804: {Additional hardware for cooling or heating of the magnet assembly, for housing a cooled or heated part of the magnet assembly or for temperature control of the magnet assembly} - H01F 6/065: {Feed-through bushings, terminals and joints (leading of conductors or axles through casings of transformers H01F27/04)} - G01R 33/3815: with superconducting coils, e.g. power supply therefor - A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B) - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract A retractable lead system is provided that includes a cup, a spherical contact, and a plunger. The cup is disposed proximate a vacuum end of the retractable lead system, and defines a cavity and a contact reception seat. The contact reception seat defines a spherical portion having a contact reception spherical radius. The spherical contact is disposed within the contact reception seat, and defines a contact spherical radius that corresponds to the contact reception spherical radius. The spherical contact is configured to be electrically coupled to an interior lead disposed within a vacuum environment. The plunger includes an ambient contact and a retractable contact disposed on opposite ends of the plunger. The plunger is configured to be actuated between an open position at which the retractable contact is retracted from the spherical contact and a closed position at which the retractable contact is coupled with the spherical contact. ## Claims ### Claim 1 A retractable lead system comprising: a cup disposed proximate a vacuum end of the retractable lead system, the cup defining a cavity and a contact reception seat, the contact reception seat defining a spherical portion having a contact reception spherical radius; a spherical contact disposed within the contact reception seat, the spherical contact defining a contact spherical radius that corresponds to the contact reception spherical radius, the spherical contact configured to be electrically coupled to an interior lead disposed within a vacuum environment; and a plunger comprising an ambient contact and a retractable contact disposed on opposite ends of the plunger, the ambient contact disposed proximate an ambient end of the retractable lead system, the plunger configured to be actuated between an open position at which the retractable contact is retracted from the spherical contact and a closed position at which the retractable contact is coupled with the spherical contact. ### Claim 2 (depends on 1) The retractable lead system of claim 1, wherein the retractable contact comprises a cylindrical contact having a radius corresponding to the contact spherical radius of the spherical contact. ### Claim 3 (depends on 1) The retractable lead system of claim 1, wherein the spherical contact includes a distal end projecting beyond the cup, the retractable lead system comprising a retention member coupled to the distal end of the spherical contact. ### Claim 4 (depends on 1) The retractable lead system of claim 1, further comprising a sealing member configured to be disposed a distance from a vacuum end plate disposed proximate a boundary of the vacuum environment and having an opening through which the plunger passes, wherein the plunger moves relative to a vacuum end plate when moved between the open and closed positions. ### Claim 5 (depends on 4) The retractable lead system of claim 4, wherein the plunger comprises a plunger sleeve disposed radially about at least a portion of the plunger, the sealing member disposed within the plunger sleeve. ### Claim 6 (depends on 5) The retractable lead system of claim 5, further comprising a bellows coupled to the plunger sleeve and interposed between the vacuum end plate and the sealing member. ### Claim 7 (depends on 5) The retractable lead system of claim 5, wherein the sealing member comprises an annular plug formed of ceramic and disposed within and coupled to the plunger sleeve. ### Claim 8 (depends on 1) The retractable lead system of claim 1, further comprising a drive stud and drive nut, the drive stud coupled to the plunger, the system further comprising a resiliently biasable spring assembly disposed radially about the drive stud. ### Claim 9 (depends on 8) The retractable lead system of claim 8, wherein the spring assembly comprises a spring cup having sides extending from a bottom, the spring cup disposed radially about the drive stud, with one or more spring members interposed between the sides of the spring cup and the drive stud. ### Claim 10 (depends on 9) The retractable lead system of claim 9, further comprising a drive spacer interposed between the drive stud and spring members. ### Claim 11 (depends on 10) The retractable lead system of claim 10, wherein the system comprises at least two plungers, the system further comprising a drive plate interposed between the spring cup and a retention nut, the drive plate coupled to the at least two plungers. ### Claim 12 A retractable lead system comprising: a cup disposed proximate a vacuum end of the retractable lead system, the cup defining a cavity and a contact reception seat; a seated contact disposed within the contact reception seat, the seated contact configured to be electrically coupled to an interior lead disposed within a vacuum environment; a plunger comprising an ambient contact and a retractable contact disposed on opposite ends of the plunger, the ambient contact disposed proximate an ambient end of the retractable lead system, the plunger configured to be actuated between an open position at which the retractable contact is retracted from the seated contact and a closed position at which the retractable contact is coupled with the seated contact; and a sealing member configured to be disposed a distance from a vacuum end plate disposed proximate a boundary of the vacuum environment and having an opening through which the plunger passes, the plunger moving relative to the vacuum end plate when moved between the open and closed positions. ### Claim 13 (depends on 12) The retractable lead system of claim 12, wherein the plunger comprises a plunger sleeve disposed radially about at least a portion of the plunger, the sealing member disposed within the plunger sleeve. ### Claim 14 (depends on 13) The retractable lead system of claim 13, further comprising a bellows coupled to the plunger sleeve and interposed between the vacuum end plate and the sealing member. ### Claim 15 (depends on 13) The retractable lead system of claim 13, wherein the sealing member comprises an annular plug formed of ceramic and disposed within and coupled to the plunger sleeve. ### Claim 16 (depends on 12) The retractable lead system of claim 12, further comprising a drive stud and drive nut, the drive stud coupled to the plunger, the system further comprising a resiliently biasable spring assembly disposed radially about the drive stud. ### Claim 17 A retractable lead system comprising: a cup disposed proximate a vacuum end of the retractable lead system, the cup defining a cavity and a contact reception seat; a seated contact disposed within the contact reception seat, the seated contact configured to be electrically coupled to an interior lead disposed within a vacuum environment; a plunger comprising an ambient contact and a retractable contact disposed on opposite ends of the plunger, the ambient contact disposed proximate an ambient end of the retractable lead system, the plunger configured to be actuated between an open position at which the retractable contact is retracted from the seated contact and a closed position at which the retractable contact is coupled with the seated contact; a drive stud and drive nut, the drive stud coupled to the plunger, and a resiliently biasable spring assembly disposed radially about the drive stud. ### Claim 18 (depends on 17) The retractable lead system of claim 17, wherein the spring assembly comprises a spring cup having sides extending from a bottom, the spring cup disposed radially about the drive stud, with one or more spring members interposed between the sides of the spring cup and the drive stud. ### Claim 19 (depends on 18) The retractable lead system of claim 18, further comprising a drive spacer interposed between the drive stud and spring members. ### Claim 20 (depends on 19) The retractable lead system of claim 19, wherein the system comprises at least two plungers, the system further comprising a drive plate interposed between the spring cup and a retention nut, the drive plate coupled to the at least two plungers.