# US 10,483,816 B2 · Motor, rotor, compressor, and refrigeration and air conditioning apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,483,816 B2 - Document ID: US10483816B2 - Status: Granted - Kind: B2 - Application number: 15/756,182 - Filed: 2015-10-30 - Published: 2018-08-30 - Granted: 2019-11-19 - Earliest claimed: 2015-10-30 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Masahiro Nigo; Kazuchika Tsuchida; Ryukichi Kijima - Web page: https://patentgrep.com/patent/US10483816B2 ## CPC - H02K 1/2766: {having a flux concentration effect} - F25B 31/026: {with compressor of rotary type} - H01F 1/057: and IIIa elements, e.g. Nd2Fe14B - H02K 1/02: characterised by the magnetic material - H02K 1/22: Rotating parts of the magnetic circuit - H02K 1/27: Rotor cores with permanent magnets - F04C 18/34: having the movement defined in group F04C18/08 or F04C18/22 and relative reciprocation between the co-operating members - F04C 2240/40: Electric motor - 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}) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES - F04C: ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS (engines F03C); ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS ## Abstract A motor includes a stator, a rotor including a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other. The rotor core has a first magnet holding portion in the magnet insertion hole, and a second magnet holding portion at an end of the magnet insertion hole in a circumferential direction. The rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction. Relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets is represented by A, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C. ## Claims ### Claim 1 A motor comprising a stator and a rotor provided inside the stator, the rotor comprising: a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other, wherein the rotor core has a first magnet holding portion disposed between the two permanent magnets adjacent to each other in the magnet insertion hole, and a second magnet holding portion disposed at an end of the magnet insertion hole in a circumferential direction of the rotor core; wherein the rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction, and wherein relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets of the rotor core is represented by A, and among the plurality of electromagnetic steel sheets of the rotor core, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C. ### Claim 2 (depends on 1) The motor according to claim 1, wherein each of the first magnet holding portion and the second magnet holding portion is a protrusion formed in the magnet insertion hole. ### Claim 3 (depends on 1) The motor according to claim 1, wherein the first magnet holding portion and the second magnet holding portion are disposed on an inner side of the magnet insertion hole in a radial direction of the rotor core. ### Claim 4 (depends on 1) The motor according to claim 1, wherein a relationship B=C is further satisfied. ### Claim 5 (depends on 4) The motor according to claim 4, wherein the plurality of electromagnetic steel sheets of the rotor core comprises: a first electromagnetic steel sheet having the first magnet holding portion and the second magnet holding portion, and a second electromagnetic steel sheet having neither the first magnet holding portion nor the second magnet holding portion. ### Claim 6 (depends on 1) The motor according to claim 1, wherein a relationship C>B is further satisfied. ### Claim 7 (depends on 6) The motor according to claim 6, wherein the plurality of electromagnetic steel sheets of the rotor core comprises: a first electromagnetic steel sheet having the first magnet holding portion and the second magnet holding portion; a second electromagnetic steel sheet having neither the first magnet holding portion nor the second magnet holding portion, and a third electromagnetic steel sheet having the second magnet holding portion but having no first magnet holding portion. ### Claim 8 (depends on 1) The motor according to claim 1, wherein the plurality of electromagnetic steel sheets of the rotor core comprises: a first electromagnetic steel sheet having the first magnet holding portion and the second magnet holding portion; a second electromagnetic steel sheet having neither the first magnet holding portion nor the second magnet holding portion; a third electromagnetic steel sheet having the second magnet holding portion but having no first magnet holding portion, and a fourth electromagnetic steel sheet having the first magnet holding portion but having no second magnet holding portion. ### Claim 9 (depends on 1) The motor according to claim 1, wherein, among the plurality of electromagnetic steel sheets of the rotor core, the electromagnetic steel sheet disposed at least one end of the rotor core in a stacking direction has at least one of the first magnet holding portion and the second magnet holding portion. ### Claim 10 (depends on 1) The motor according to claim 1, wherein each of the plurality of permanent magnets is a rare earth magnet containing neodymium (Nd), iron (Fe) and boron (B) as principal components, and exhibits a residual magnetic flux density in a range from 1.27 T to 1.42 T at 20° C. and a coercivity in a range from 1671 kA/m to 1922 kA/m at 20° C. ### Claim 11 (depends on 1) The motor according to claim 1, wherein the magnet insertion hole has a V-shape such that a center portion of the magnet insertion hole in the circumferential direction protrudes inward in a radial direction of the rotor core. ### Claim 12 (depends on 1) The rotor according to claim 1, wherein the magnet insertion hole extends straight, and the plurality of the permanent magnets comprises two permanent magnets. ### Claim 13 (depends on 1) The motor according to claim 1, wherein the plurality of permanent magnets comprises three permanent magnets. ### Claim 14 (depends on 1) The motor according to claim 1, wherein the rotor core has an opening on an inner side of the first magnet holding portion in a radial direction; wherein the rotor core has a center hole at a center in the radial direction, and wherein a distance from the opening to the magnet insertion hole is shorter than a distance from the opening to the center hole. ### Claim 15 A rotor comprising: a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other, wherein the rotor core has a first magnet holding portion disposed between the two permanent magnets adjacent to each other in the magnet insertion hole, and a second magnet holding portion disposed at an end of the magnet insertion hole in a circumferential direction of the rotor core; wherein the rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction, and wherein relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets of the rotor core is represented by A, and among the plurality of electromagnetic steel sheets of the rotor core, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C. ### Claim 16 A compressor comprising a motor and a compression mechanism driven by the motor, the motor comprising a stator and a rotor provided inside the stator, the rotor comprising: a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other, wherein the rotor core has a first magnet holding portion disposed between the two permanent magnets adjacent to each other in the magnet insertion hole, and a second magnet holding portion disposed at an end of the magnet insertion hole in a circumferential direction of the rotor core; wherein the rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction, and wherein relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets of the rotor core is represented by A, and among the plurality of electromagnetic steel sheets of the rotor core, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C. ### Claim 17 A refrigeration and air conditioning apparatus comprising a compressor, a condenser, a decompression device and an evaporator, the compressor comprising a motor and a compression mechanism driven by the motor, the motor comprising a stator and a rotor provided inside the stator, the rotor comprising: a rotor core having a magnet insertion hole, and a plurality of permanent magnets disposed in the magnet insertion hole of the rotor core and having two permanent magnets adjacent to each other, wherein the rotor core has a first magnet holding portion disposed between the two permanent magnets adjacent to each other in the magnet insertion hole, and a second magnet holding portion disposed at an end of the magnet insertion hole in a circumferential direction of the rotor core; wherein the rotor core has a plurality of electromagnetic steel sheets stacked in an axial direction, and wherein relationships A>B and A>C are satisfied, where a number of the plurality of electromagnetic steel sheets of the rotor core is represented by A, and among the plurality of electromagnetic steel sheets of the rotor core, a number of electromagnetic steel sheets having the first magnet holding portions is represented by B, and a number of electromagnetic steel sheets having the second magnet holding portions is represented by C.