# US 2018/0320760 A1 · Self-aligning virtual elliptical drive > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0320760 A1 - Document ID: US20180320760A1 - Status: Published application - Kind: A1 - Application number: 15/585,544 - Filed: 2017-05-03 - Published: 2018-11-08 - Earliest claimed: 2017-05-03 - Assignees: The Boeing Company - Applicants: The Boeing Company - Inventors: Robert J. Atmur; William Patrick Sargent - Web page: https://patentgrep.com/patent/US20180320760A1 ## CPC - F16H 1/321: {the orbital gear being nutating} - F16H 23/00: Wobble-plate gearings; Oblique-crank gearings - H02K 7/08: Structural association with bearings - H02K 7/116: with gears - H02K 7/14: Structural association with mechanical loads, e.g. with hand-held machine tools or fans (with fan or impeller for cooling the machine H02K9/06) - F16H: GEARING - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract A self-aligning wobble plate drive, including a stator gear, a wobble plate, and an output plate. The stator gear has a central stator axis and a plurality of stator teeth. The wobble plate has a wobble axis, a plurality of face teeth, and a plurality of wobble teeth, and is disposed such that the wobble axis is at a non-zero wobble angle relative to the stator axis. The output plate includes a plurality of output teeth and is substantially aligned with the stator axis. At least two of the pluralities of teeth are configured to engage with each other in a self-aligning manner such that as the wobble plate nutates around the stator gear, the wobble angle remains constant. ## Claims ### Claim 1 A wobble plate drive, comprising: a stator gear having a central stator axis and a plurality of stator teeth disposed on an inner cylindrical surface; a wobble plate having a wobble axis disposed at a non-zero wobble angle relative to the stator axis, an engaging face perpendicular to the wobble axis, a plurality of face teeth disposed on the engaging face, and a plurality of wobble teeth disposed around a perimeter of the wobble plate and configured to engage with the stator teeth; and an output plate substantially aligned with the stator axis and having a plurality of output teeth configured to engage with the face teeth; wherein at least two of the pluralities of teeth are configured to engage with each other in a self-aligning manner such that as the wobble plate nutates around the stator gear, the wobble angle remains constant. ### Claim 2 (depends on 1) The wobble plate drive of claim 1, wherein: at least one of the wobble teeth is wedge shaped, with a surface of the at least one wobble tooth defining a first line extendable through a center of mass of the wobble plate; and at least one of the stator teeth is wedge shaped, with a surface of the at least one stator tooth defining a second line extendable through a center of mass of the wobble plate. ### Claim 3 (depends on 1) The wobble plate drive of claim 1, wherein: The face teeth are disposed on a frustoconical surface of the wobble plate such that a center of mass of the wobble plate coincides with a vertex of the frustoconical surface of the wobble plate; and the output teeth are disposed on a frustoconical surface of the output plate such that the center of mass of the wobble plate coincides with a vertex of the frustoconical surface of the output plate. ### Claim 4 (depends on 1) The wobble plate drive of claim 1, wherein the wobble plate is constrained such that during nutation no part of the wobble plate is more than a predetermined distance from the stator gear. ### Claim 5 (depends on 1) The wobble plate drive of claim 1, wherein the wobble teeth and the face teeth extend in opposite directions parallel to the wobble axis, and the wobble plate is disposed between the stator gear and the output plate. ### Claim 6 (depends on 1) The wobble plate drive of claim 1, wherein the wobble teeth and the face teeth extend in the same direction parallel to the wobble axis, and the stator gear is disposed between the wobble plate and the output plate. ### Claim 7 (depends on 6) The wobble plate drive of claim 6, further comprising a motor configured to induce nutation of the wobble plate about the stator gear, wherein nutation of the wobble plate about the stator gear causes the wobble plate to rotate, and rotation of the wobble plate causes the output plate to rotate. ### Claim 8 (depends on 7) The wobble plate drive of claim 7, wherein: the motor is an electric motor having a substantially flat surface and at least one round protrusion extending from the substantially flat surface; the wobble plate has a substantially flat face opposite the engaging face; and the at least one round protrusion is configured to engage with the substantially flat face of the wobble plate. ### Claim 9 (depends on 7) The wobble plate drive of claim 7, wherein: the motor includes a permanent magnet and a set of electromagnetic coils; the wobble plate is made of a magnetically susceptible material; and the permanent magnet and the set of electromagnetic coils are collectively configured to create a magnetic field between the motor and the wobble plate with a highest flux density at a mobile location. ### Claim 10 A wobble plate drive, comprising: a stator gear having a central stator axis and a plurality of stator teeth disposed on an inner cylindrical surface; a wobble plate having a wobble axis disposed at a non-zero wobble angle relative to the stator axis, an engaging face perpendicular to the wobble axis, a plurality of face teeth disposed on the engaging face, and a plurality of wobble teeth disposed around a perimeter of the wobble plate in a plane perpendicular to both the engaging face and the wobble axis; and an output plate substantially aligned with the stator axis and having a plurality of output teeth configured to engage with the face teeth; and means for self-aligning engagement of the stator teeth with the wobble teeth, such that the wobble angle remains constant as the wobble plate nutates around the stator gear. ### Claim 11 (depends on 10) The wobble plate drive of claim 10, wherein: at least one of the wobble teeth is wedge shaped, with a surface of the at least one wobble tooth defining a first line extendable through a center of mass of the wobble plate; and at least one of the stator teeth is wedge shaped, with a surface of the at least one stator tooth defining a second line extendable through a center of mass of the wobble plate. ### Claim 12 (depends on 10) The wobble plate drive of claim 10, wherein: the face teeth are disposed on a frustoconical surface of the wobble plate such that a center of mass of the wobble plate coincides with a vertex of the frustoconical surface of the wobble plate; and the output teeth are disposed on a frustoconical surface of the output plate such that the center of mass of the wobble plate coincides with a vertex of the frustoconical surface of the output plate. ### Claim 13 (depends on 10) The wobble plate drive of claim 10, wherein the wobble plate is constrained such that during nutation no part of the wobble plate is more than a predetermined distance from the stator gear. ### Claim 14 (depends on 10) The wobble plate drive of claim 10, wherein the wobble teeth and the face teeth extend in opposite directions parallel to the wobble axis, and the wobble plate is disposed between the stator gear and the output plate. ### Claim 15 (depends on 10) The wobble plate drive of claim 10, wherein the wobble teeth and the face teeth extend in the same direction parallel to the wobble axis, and the stator gear is disposed between the wobble plate and the output plate. ### Claim 16 A method of operating a wobble plate drive, comprising: providing a stator gear, a wobble plate, and an output plate; engaging a plurality of stator teeth of the stator gear with a plurality of wobble teeth of the wobble plate in a self-aligning manner; engaging a plurality of face teeth of the wobble plate with a plurality of output teeth of the output plate in a self-aligning manner; and inducing nutation of the wobble plate about the stator gear. ### Claim 17 (depends on 16) The method of claim 16, wherein inducing nutation of the wobble plate includes: energizing a motor to rotate about a rotation axis, the motor having a substantially flat surface and at least one rounded protrusion extending from the substantially flat surface; and engaging the at least one rounded protrusion with a substantially flat surface of the wobble plate, thereby causing the wobble plate to nutate. ### Claim 18 (depends on 16) The method of claim 16, wherein inducing nutation of the wobble plate includes: energizing a motor including a permanent magnet and a set of electromagnetic coils to create a magnetic field between the motor and the wobble plate with a highest flux density at a mobile location, thereby causing the wobble plate to nutate. ### Claim 19 (depends on 16) The method of claim 16, wherein: inducing nutation of the wobble plate includes rotating the output plate; rotating the output plate when the face teeth are engaged with the output teeth causes the wobble plate to rotate; and rotation of the wobble plate when the stator teeth are engaged with the wobble teeth causes the wobble plate to nutate. ### Claim 20 (depends on 16) The method of claim 16, further including constraining the wobble plate such that during nutation no part of the wobble plate is more than a predetermined distance from the stator gear.