# US 12,184,138 B2 · Motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,184,138 B2 - Document ID: US12184138B2 - Status: Granted - Kind: B2 - Application number: 17/786,957 - Filed: 2021-01-26 - Published: 2023-02-09 - Granted: 2024-12-31 - Earliest claimed: 2020-01-27 - Assignees: Nsk Ltd. - Applicants: Nsk Ltd. - Inventors: Toshifumi Taguchi; Hayao Watanabe; Masayuki Maruyama; Kenichi Fukuyama - Web page: https://patentgrep.com/patent/US12184138B2 ## CPC - H02K 24/00: Machines adapted for the instantaneous transmission or reception of the angular displacement of rotating parts, e.g. synchro, selsyn - G05B 15/02: electric - H02K 1/02: characterised by the magnetic material - H02K 1/185: {to outer stators} - H02K 5/12: specially adapted for operating in liquid or gas (combined with cooling arrangements H02K9/00) - H02K 5/124: Sealing of shafts - H02K 5/128: using air-gap sleeves or air-gap discs - H02K 5/1732: {radially supporting the rotary shaft at both ends of the rotor (H02K5/1737 takes precedence)} - H02K 5/1737: {radially supporting the rotor around a fixed spindle; radially supporting the rotor directly} - H02K 7/083: {radially supporting the rotary shaft at both ends of the rotor (H02K7/086, H02K7/09 take precedence)} - H02K 7/086: {radially supporting the rotor around a fixed spindle; radially supporting the rotor directly (H02K7/09 takes precedence)} - H02K 11/225: Detecting coils - H02K 11/33: Drive circuits, e.g. power electronics (H02K11/38 takes precedence) - H02K 21/16: having annular armature cores with salient poles (with homopolar co-operation H02K21/20) - H02K 2213/03: Machines characterised by numerical values, ranges, mathematical expressions or similar information - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract A motor includes a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, and a resolver that is configured to detect rotation of the motor rotor. ## Claims ### Claim 1 A motor comprising: a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, a resolver that is configured to detect rotation of the motor rotor, and a motor partition wall that is provided between the motor stator and the motor rotor to separate a space in which the motor stator is disposed from a space in which the motor rotor is disposed, wherein the resolver is provided outward in a radial direction with respect to the bearing and provided on an opposite side to the housing base in an axial direction with respect to the motor stator, in a direction along the rotation center axis, the resolver includes a resolver rotor that is coupled to the motor rotor and a resolver stator that is provided outward in a radial direction of the resolver rotor and has an excitation coil, and a resolver partition wall is provided between the resolver rotor and the resolver stator. ### Claim 2 (depends on 1) The motor according to claim 1, wherein an outer diameter of the motor rotor is smaller than an outer diameter of the resolver rotor. ### Claim 3 A motor comprising: a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, and a resolver that is configured to detect rotation of the motor rotor, wherein the resolver is provided outward in a radial direction with respect to the bearing and provided on an opposite side to the housing base in an axial direction with respect to the motor stator, in a direction along the rotation center axis, the bearing is lubrication-free and includes an inner ring that is provided on the housing shaft portion, an outer ring that is provided on the motor rotor, and a rolling element that is provided between the inner ring and the outer ring, and among the inner ring, the outer ring, and the rolling element, at least the rolling element is made of ceramics. ### Claim 4 (depends on 1) The motor according to claim 1, wherein the bearing is lubrication-free and has an inner ring that is provided on the housing shaft portion, an outer ring that is provided on the motor rotor, and a rolling element that is provided between the inner ring and outer ring, and the inner ring and the outer ring are made of a magnetic iron-based material. ### Claim 5 (depends on 1) The motor according to claim 1, wherein a coupling portion that is formed of a magnetic material is disposed between the motor stator and the resolver in the direction along the rotation center axis. ### Claim 6 A motor comprising: a housing including a housing base and a housing shaft portion that is provided on the housing base and extends in a direction along a rotation center axis, a motor stator that is disposed outward in a radial direction of the housing shaft portion, a motor rotor that is provided between the motor stator and the housing shaft portion, a bearing that is provided inward in a radial direction of the motor rotor and rotatably supports the motor rotor to the housing shaft portion, a sealing structure that is provided on an opposite side to the housing base in an axial direction of the motor rotor and seals between the motor rotor and the housing shaft portion, a resolver that is configured to detect rotation of the motor rotor, an outer ring pressing portion that is provided on an opposite side to the housing base in the axial direction of the motor rotor and is fixed to the outer ring of the bearing; and an inner ring pressing portion that is provided on an opposite side to the housing base in an axial direction of the housing shaft portion and is fixed to the inner ring of the bearing, wherein the resolver is provided outward in a radial direction with respect to the bearing and provided on the opposite side to the housing base in an axial direction with respect to the motor stator, in the direction along the rotation center axis, and the sealing structure has a labyrinth structure that is formed with the outer ring pressing portion and the inner ring pressing portion. ### Claim 7 (depends on 1) The motor according to claim 1, wherein the motor stator is disposed in a space on an atmospheric side with respect to a space in which the motor rotor is disposed. ### Claim 8 (depends on 1) The motor according to claim 1, wherein the motor rotor includes a samarium-cobalt permanent magnet. ### Claim 9 (depends on 1) The motor according to claim 1, further comprising a motor control circuit that is configured to supply a drive current to the excitation coil of the motor stator based on a detection signal of the resolver.