# US 2019/0245397 A1 · Electric drive motor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0245397 A1 - Document ID: US20190245397A1 - Status: Published application - Kind: A1 - Application number: 16/341,934 - Filed: 2017-10-04 - Published: 2019-08-08 - Earliest claimed: 2016-10-13 - Assignees: BSH Hausgeraete GmbH - Applicants: Bsh Hausgeraete GmbH - Inventors: MARTIN IVANAK; MICHAL KALAVSKY - Web page: https://patentgrep.com/patent/US20190245397A1 ## CPC - H02K 1/278: Surface mounted magnets; Inset magnets - F04B 17/03: driven by electric motors - H02K 1/30: using intermediate parts, e.g. spiders - H02K 15/03: having permanent magnets - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - F04B: POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F) ## Abstract An electric drive motor includes a stator with pole shoes and at least one electrically actuable stator winding, a permanent-magnet rotor mounted in a rotationally driveable manner in the field of the stator winding defining an annular gap therebetween, a motor shaft, a magnet carrier disposed on the motor shaft and being produced in one piece as an injection-molded part, and a plurality of separate permanent magnets disposed on and distributed over the circumference of the magnet carrier. The permanent magnet rotor has a tensioning or clamping device for pressing the plurality of permanent magnets outwards in radial directions towards against an inner wall of a cavity in an injection mold of the magnet carrier during injection molding of the magnet carrier. A domestic appliance having the electric drive motor is also provided. ## Claims ### Claim at position 1 -12. (canceled) ### Claim 13 An electric drive motor, comprising: a stator having pole shoes and at least one electrically actuatable stator winding having a field; a permanent-magnet rotor rotatably and drivably mounted in the field of said stator winding and defining an annular gap between said rotor and said stator, said rotor having a tensioning device; a motor shaft; an injection-molded magnet carrier disposed on said motor shaft, said magnet carrier having a circumference and an injection mold with a cavity defining an inner wall; and a plurality of separate permanent magnets disposed on said magnet carrier and distributed over said circumference of said magnet carrier, said plurality of permanent magnets being pushed in radial directions outwardly against said inner wall by said tensioning device during injection molding of said magnet carrier. ### Claim 14 (depends on 13) The electric drive motor according to claim 13, wherein said tensioning device forms a magnetic yoke providing a return path for magnetic fields of said plurality of permanent magnets. ### Claim 15 (depends on 13) The electric drive motor according to claim 13, wherein said tensioning device includes at least two part shells being assembled together in the circumferential direction and complementing each other to form a two-part or multi-part annular body forming an outwardly curved surface wall against which said plurality of permanent magnets rest flush. ### Claim 16 (depends on 15) The electric drive motor according to claim 15, wherein said at least two part shells are axially adjustable relative to one another, causing said at least two part shells to be moved outwards in radial directions and to press said plurality of permanent magnets outwards in radial directions against said inner wall of said cavity of said injection mold of said magnet carrier during an axial adjustment of at least one of said at least two part shells. ### Claim 17 (depends on 16) The electric drive motor according to claim 16, wherein: each said part shell has a basic shape extending in a circle arc shape about an axial symmetry line and including a circle sector-shaped, convex outwardly curved surface wall, a circle sector-shaped, concave inwardly curved surface wall, a first end face wall pointing in the circumferential direction in a direction of rotation of said permanent-magnet rotor, and a second end face wall pointing in the circumferential direction against said direction of rotation of said permanent-magnet rotor; said first end face wall and said second end face wall each lying in a plane disposed in a direction of the axial line of symmetry forming an axis of rotation of said permanent-magnet rotor; and said planes being disposed about an obliquely running rotated angle perpendicular to the axial line of symmetry. ### Claim 18 (depends on 17) The electric drive motor according to claim 17, wherein said angle is between 1 degree and 20 degrees. ### Claim 19 (depends on 18) The electric drive motor according to claim 18, wherein said angle is at least substantially 12 degrees. ### Claim 20 (depends on 13) The electric drive motor according to claim 13, wherein said tensioning device or said at least one part shell is formed of a ferritic chromium steel. ### Claim 21 (depends on 15) The electric drive motor according to claim 15, wherein each of said permanent magnets has a convex magnetic outer surface facing radially outwards and an opposite concave magnetic inner surface facing radially inwards, and said outwardly curved surface walls of said tensioning device or said part shells rest flush against said concave magnetic inner surface. ### Claim 22 (depends on 15) The electric drive motor according to claim 15, wherein each of said permanent magnets has a convex magnetic outer surface facing radially outwards and forming at least a part of said outwardly curved surface wall of said permanent-magnet rotor directly delimiting said annular gap from inside. ### Claim 23 (depends on 21) The electric drive motor according to claim 21, wherein said convex magnetic outer surface of each of said permanent magnets has a longitudinal groove extending in an axial direction. ### Claim 24 (depends on 22) The electric drive motor according to claim 22, wherein said convex magnetic outer surface of each of said permanent magnets has a longitudinal groove extending in an axial direction. ### Claim 25 (depends on 13) The electric drive motor according to claim 13, wherein each of said permanent magnets has one or more edges provided with a chamfer. ### Claim 26 (depends on 13) A household appliance, dishwasher, washing machine, dryer, extractor hood or household appliance pump, comprising an electric drive motor according to claim 13. ### Claim 27 A method for producing an electric drive motor, the method comprising the following steps: injection-molding a magnet carrier in an injection mold having a cavity defining an inner wall; distributing a plurality of separate permanent magnets over a circumference of the magnet carrier; using a tensioning device of a permanent-magnet rotor to push the plurality of permanent magnets in radial directions outwardly against the inner wall during the injection molding of the magnet carrier; placing the magnet carrier on a motor shaft; providing a stator having pole shoes and at least one electrically actuatable stator winding having a field; and rotatably and drivably mounting the permanent-magnet rotor in the field of the stator winding and defining an annular gap between the rotor and the stator.