# US 12,191,710 B2 · Electric motor for a power tool > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,191,710 B2 - Document ID: US12191710B2 - Status: Granted - Kind: B2 - Application number: 18/366,378 - Filed: 2023-08-07 - Published: 2023-11-30 - Granted: 2025-01-07 - Earliest claimed: 2020-02-05 - Assignees: Milwaukee Electric Tool Corporation - Applicants: Milwaukee Electric Tool Corporation - Inventors: Andrew T. Beyerl; Derek J. Schwab; Samantha L. Billetdeaux; Kyle Greunke; Hans T. Banholzer; Carmen J. Castanos - Web page: https://patentgrep.com/patent/US12191710B2 ## CPC - B25F 5/02: Construction of casings, bodies or handles {(B25F5/006, B25F5/008 take precedence)} - H02K 1/185: {to outer stators} - B23D 51/16: of drives or feed mechanisms for straight tools, e.g. saw blades, or bows - B25F 5/008: {Cooling means} - H02K 1/146: {consisting of a generally annular yoke with salient poles} - H02K 1/276: Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM] - H02K 3/522: {for generally annular cores with salient poles} - H02K 5/161: {radially supporting the rotary shaft at both ends of the rotor (H02K5/165, H02K5/167, H02K5/173 take precedence)} - H02K 5/1732: {radially supporting the rotary shaft at both ends of the rotor (H02K5/1737 takes precedence)} - H02K 7/083: {radially supporting the rotary shaft at both ends of the rotor (H02K7/086, H02K7/09 take precedence)} - H02K 7/145: {Hand-held machine tool} - H02K 9/06: with fans or impellers driven by the machine shaft - H02K 9/227: {Heat sinks} - 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 2211/03: Machines characterised by circuit boards, e.g. pcb - B25F: COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR {(machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass B23P23/00 and subgroups)} - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - B23D: PLANING; SLOTTING; SHEARING; BROACHING; SAWING; FILING; SCRAPING; LIKE OPERATIONS FOR WORKING METAL BY REMOVING MATERIAL, NOT OTHERWISE PROVIDED FOR (making toothed gears or the like B23F; cutting metal by applying heat locally B23K; arrangements for copying or controlling B23Q) ## Abstract An electric motor assembly includes a circuit board, a rotor assembly, and a stator assembly having a first end coupled to the circuit board and a second end opposite the first end. The stator assembly also includes an annular stator body having a plurality of inwardly projecting teeth. The stator assembly further includes windings wrapped about the stator body to form a plurality of coils. The stator assembly also includes a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end. The terminal is coupled to the circuit board at the first end and is coupled to the windings at the second end to electrically connect the windings to the circuit board. The terminal is molded to an attachment member, and the attachment member is molded to the outer periphery of the stator body. ## Claims ### Claim 1 An electric motor assembly comprising: a circuit board; a rotor assembly; a stator assembly having a first end coupled to the circuit board and a second end opposite the first end, the stator assembly including a stator body having a plurality of inwardly projecting teeth, windings wrapped about the stator body to form a plurality of coils, and a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end, the terminal being coupled to the circuit board at the first end and being coupled to the windings at the second end to electrically connect the windings to the circuit board; and a heat sink positioned between the stator assembly and the circuit board, the heat sink including a plurality of axially extending cooling flanges; wherein the terminal is molded to an attachment member, and the attachment member is molded to the outer periphery of the stator body. ### Claim 2 (depends on 1) The electric motor assembly of claim 1, wherein the terminal includes a central plate portion, a connecting portion extending from the central plate portion and electrically coupled to the circuit board at the first end, and a hook portion extending from the central plate portion and configured to engage the windings at the second end. ### Claim 3 (depends on 1) The electric motor assembly of claim 1, wherein the heat sink is in thermal contact with the circuit board, wherein the heat sink includes an end wall defining a bearing pocket, and wherein the plurality of axially extending cooling flanges extend from a periphery of the end wall. ### Claim 4 (depends on 3) The electric motor assembly of claim 3, wherein each cooling flange defines an airflow aperture. ### Claim 5 (depends on 1) The electric motor assembly of claim 1, wherein the terminal includes a connecting portion that protrudes through the circuit board. ### Claim 6 (depends on 5) The electric motor assembly of claim 5, wherein the connecting portion is defined at the first end, and wherein the terminal further includes a hook portion defined at the second end and engaged with the windings. ### Claim 7 (depends on 1) The electric motor assembly of claim 1, wherein the stator body includes an insulator member having a retaining wall that engages the attachment member to secure the attachment member to the stator body. ### Claim 8 An electric motor assembly comprising: a circuit board; a rotor assembly; a stator assembly having a first end coupled to the circuit board and a second end opposite the first end, the stator assembly including a stator body having a plurality of teeth, windings wrapped about the stator body to form a plurality of coils, and a terminal configured to electrically connect the windings to the circuit board; and a heat sink positioned between the stator assembly and the circuit board, the heat sink including a plurality of axially extending cooling flanges. ### Claim 9 (depends on 8) The electric motor assembly of claim 8, wherein the heat sink further includes an end wall, and wherein each cooling flange extends from a periphery of the end wall. ### Claim 10 (depends on 8) The electric motor assembly of claim 8, wherein the heat sink further includes an end wall that defines a bearing pocket. ### Claim 11 (depends on 10) The electric motor assembly of claim 10, further comprising a bearing received within the bearing pocket that rotatably supports the rotor assembly. ### Claim 12 (depends on 8) The electric motor assembly of claim 8, wherein each cooling flange defines an airflow aperture. ### Claim 13 (depends on 8) The electric motor assembly of claim 8, wherein the terminal includes a connecting portion that protrudes through the circuit board. ### Claim 14 (depends on 13) The electric motor assembly of claim 13, wherein the connecting portion is located at the first end, and wherein the terminal further includes a hook portion located at the second end and engaged with the windings. ### Claim 15 An electric motor assembly comprising: a circuit board; a rotor assembly; a stator assembly having a first end coupled to the circuit board and a second end opposite the first end, the stator assembly including a stator body having a plurality of teeth, windings wrapped about the stator body to form a plurality of coils, and a terminal coupled to an outer periphery of the stator body and extending longitudinally between the first end and the second end, the terminal being coupled to the circuit board at the first end and being coupled to the windings at the second end to electrically connect the windings to the circuit board; and a heat sink positioned between the stator assembly and the circuit board, the heat sink including a plurality of axially extending cooling flanges, wherein the heat sink is in thermal contact with the circuit board. ### Claim 16 (depends on 15) The electric motor assembly of claim 15, wherein the terminal is secured to an attachment member, and wherein the attachment member is secured to the outer periphery of the stator body. ### Claim 17 (depends on 16) The electric motor assembly of claim 16, wherein the stator body includes an insulator member having a retaining wall that engages the attachment member to secure the attachment member to the stator body. ### Claim 18 (depends on 16) The electric motor assembly of claim 16, wherein the terminal is insert molded to the attachment member. ### Claim 19 (depends on 18) The electric motor assembly of claim 18, wherein the attachment member is insert molded to the stator body. ### Claim 20 (depends on 15) The electric motor assembly of claim 15, wherein the heat sink includes an end wall that defines a bearing pocket in which a bearing is received to rotatably support the rotor assembly.