# US 2021/0281133 A1 · Motor and washing machine having the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0281133 A1 - Document ID: US20210281133A1 - Status: Published application - Kind: A1 - Application number: 17/191,894 - Filed: 2021-03-04 - Published: 2021-09-09 - Earliest claimed: 2020-03-06 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Ukho SEO; Deokjin KIM; Yongwoo NAM; Jaewoong JUNG - Web page: https://patentgrep.com/patent/US20210281133A1 ## CPC - H02K 1/2791: Surface mounted magnets; Inset magnets - D06F 37/304: {Arrangements or adaptations of electric motors} - H02K 1/2786: Outer rotors - H02K 1/30: using intermediate parts, e.g. spiders - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES ## Abstract A washing machine includes a motor. The washing machine includes a cabinet, a tub arranged inside the cabinet, a drum rotatively arranged inside the tub, and the motor. The motor includes a stator arranged on the rear wall of the tub, and a rotor. The stator is arranged to rotate by electromagnetically interacting with the stator. The rotor includes a plurality of rotor cores alternatingly arranged with a plurality of magnets in a radial form. Each of the rotor cores includes a body, a tooth formed in the front end part of the body, a first groove formed in the upper part of the body, and a second groove formed in the lower part of the body. A partition between the first and second grooves constitutes a part of the body providing an interval between the first and second grooves. ## Claims ### Claim 1 A washing machine comprising: a cabinet; a tub inside the cabinet; a drum configured to be rotatable inside the tub; and a motor including a stator on a rear wall of the tub, and a rotor configured to rotate by electromagnetically interacting with the stator, the rotor including a plurality of rotor cores and a plurality of magnets arranged alternately and radially with the plurality of rotor cores, each of the rotor cores having a body including: a tooth in a front part of the body, a first groove in an upper part of the body, a second groove in a lower part of the body, and a partition separating the first groove from the second groove. ### Claim 2 (depends on 1) The washing machine of claim 1, wherein a thickness of the partition extending in a longitudinal direction of the body, is different from depths of the first and second grooves. ### Claim 3 (depends on 1) The washing machine of claim 1, wherein the body includes a plurality of partitions spaced at intervals. ### Claim 4 (depends on 3) The washing machine of claim 3, further comprising resin introducing spaces opened toward a front part of the body. ### Claim 5 (depends on 1) The washing machine of claim 1, wherein the first and second grooves are symmetrical with each other. ### Claim 6 (depends on 5) The washing machine of claim 5, wherein each of the first and second grooves has a front end and rear end which are symmetrical. ### Claim 7 (depends on 6) The washing machine of claim 6, wherein the first and second grooves have center portions which are different from widths of the front end and the rear end. ### Claim 8 (depends on 6) The washing machine of claim 6, wherein the first and second grooves have widths which are the same in the longitudinal direction. ### Claim 9 (depends on 5) The washing machine of claim 5, wherein the front end and the read end of the first and second grooves are asymmetric. ### Claim 10 (depends on 1) The washing machine of claim 1, wherein the first groove or the second groove is connected to a slit on a rear end of the body. ### Claim 11 (depends on 1) The washing machine of claim 1, further comprising: a penetration hole extending from the upper part to the lower part of the body. ### Claim 12 (depends on 1) The washing machine of claim 1, further comprising: a third groove in the upper part of the body; a fourth groove in the lower part of the body; and another partition in the body between the third groove and the fourth groove. ### Claim 13 (depends on 12) The washing machine of claim 12, wherein the third and fourth grooves are symmetrical. ### Claim 14 (depends on 12) The washing machine of claim 12, wherein each of the third groove and the fourth groove is connected to a corresponding one of resin introducing holes on a side surface of the body. ### Claim 15 (depends on 1) The washing machine of claim 1, wherein the rotor includes a frame having an inner circumferential surface to which the plurality of magnets and the plurality of rotor cores are fixed, and the frame is integrally formed with a serration to which the plurality of magnets, the plurality of rotor cores, and a driving axis are coupled. ### Claim 16 (depends on 1) The washing machine of claim 1, wherein the frame includes a part extending into the first groove or the second groove of each of the plurality of rotor cores. ### Claim 17 (depends on 1) The washing machine of claim 1, wherein the stator includes a stator core having a plurality of teeth on an outer circumference, and an aluminum coil wound around the plurality of teeth. ### Claim 18 A motor comprising: a stator; and a rotor configured to rotate by electromagnetically interacting with the stator, the rotor including: a plurality of rotor cores and a plurality of magnets arranged alternately and radially with the plurality of rotor cores; a serration configured to be coupled to a driving axis; and a circular frame injection molded with the plurality of rotor cores, the plurality of magnets, and the serration, each of the plurality of rotor cores including a body having: a first groove and a second groove in an upper part and a lower part of the body, respectively, to which a resin is introduced during injection molding, and a partition between the first and second grooves. ### Claim 19 (depends on 18) The motor of claim 18, wherein a thickness of the partition in a longitudinal direction of the body is different from depths of the first and second grooves. ### Claim 20 (depends on 18) The motor of claim 18, further comprising: a third groove in the upper part of the body; a fourth groove in the lower part of the body; and another partition between the third groove and the fourth groove.