# US 2021/0242764 A1 · Magnetic transmission > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242764 A1 - Document ID: US20210242764A1 - Status: Published application - Kind: A1 - Application number: 17/106,855 - Filed: 2020-11-30 - Published: 2021-08-05 - Earliest claimed: 2020-01-31 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: Martin Culpepper; Marcel Thomas - Web page: https://patentgrep.com/patent/US20210242764A1 ## CPC - H02K 41/02: Linear motors; Sectional motors - H02K 49/106: {with a radial air gap} - H02K 7/06: Means for converting reciprocating motion into rotary motion or vice versa - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract Magnetic transmissions and related methods are described. In one embodiment, an apparatus includes a magnetic screw comprising an elongate body, a nut selectively magnetically coupled to the magnetic screw, and a potential energy storage system and/or a resistive force component. The nut is configured to be displaced relative to the elongate body in a first direction in response to manipulation of a magnetic field between the magnetic screw and the nut when the nut is magnetically coupled to the magnetic screw. In embodiments including a potential energy storage system, the potential energy storage system may store potential energy when the nut is displaced in the first direction. In embodiments including a resistive force component, the resistive force component may resist motion of the nut in the first direction by applying a resistive force to the nut at least partially in an opposing second direction. ## Claims ### Claim 1 An apparatus comprising: a magnetic screw comprising an elongate body; a nut selectively magnetically coupled to the magnetic screw, the nut configured to be displaced relative to the elongate body in a first direction in response to manipulation of a magnetic field between the magnetic screw and the nut when the nut is magnetically coupled to the magnetic screw; and a potential energy storage system configured to store potential energy when the nut is displaced in the first direction. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein an air gap is disposed between the nut and the magnetic screw. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the potential energy storage system comprises a spring. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the potential energy storage system comprises a magnet configured to store magnetic potential energy. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the potential energy storage system is further configured to release the stored potential energy. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the apparatus is backdrivable. ### Claim 7 A method comprising: manipulating a magnetic field between a nut and a magnetic screw to displace the nut relative to the magnetic screw in a first direction; and storing potential energy when the nut is displaced in the first direction. ### Claim 8 (depends on 7) The method of claim 7, further comprising releasing the stored potential energy. ### Claim 9 (depends on 8) The method of claim 8, wherein releasing the stored potential energy includes magnetically decoupling the nut and magnetic screw. ### Claim 10 (depends on 7) The method of claim 7, wherein storing potential energy includes storing elastic potential energy. ### Claim 11 (depends on 7) The method of claim 7, wherein storing potential energy includes storing magnetic potential energy. ### Claim 12 (depends on 7) The method of claim 7, wherein displacing the nut includes one or more selected from the group of translating the nut along a longitudinal axis of the magnetic screw and rotating the nut about the longitudinal axis of the magnetic screw. ### Claim 13 An apparatus comprising: a magnetic screw comprising an elongate body; a nut selectively magnetically coupled to the magnetic screw, the nut configured to be displaced relative to the elongate body in a first direction in response to manipulation of a magnetic field between the magnetic screw and the nut when the nut is magnetically coupled to the magnetic screw; and a resistive force component configured to resist a force when the nut is displaced in the first direction. ### Claim 14 (depends on 13) The apparatus of claim 13, wherein the resistive force component comprises a dissipative load component. ### Claim 15 (depends on 14) The apparatus of claim 14, wherein the dissipative load component comprises a dashpot. ### Claim 16 (depends on 14) The apparatus of claim 14, wherein the resistive force component is configured to resist motion of the nut in the first direction. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the resistive force component is configured to resist motion of the nut in the first direction by applying a resistive force to the nut at least partially in an opposing second direction. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the resistive force component comprises a dissipative load component. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein the dissipative load component comprises a dashpot. ### Claim 20 (depends on 14) The apparatus of claim 14, further comprising a potential energy storage system configured to store potential energy when the nut is displaced in the first direction.