Motor stator with improved end surface insulating plate, motor including the motor stator, pump including the motor stator, and manufacturing the motor stator

• US 7,936,116 B2
• Filed: 02/26/2007
• Issued: 05/03/2011
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: Auto Tech Group LLC
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Yamazaki, Tougo, Ishii, Hiroyuki, Asou, Hiroki, Yamamoto, Mineo, Kawakubo, Mamoru
• Primary Examiner(s): Leung; Quyen
• Assistant Examiner(s): KENERLY, TERRANCE L
• Application Number:
  US12/159,674
• Publication Number:
  US 20100264757A1
• Time in Patent Office: 1,527 Days
• Field of Search: 310/71, 310/43, 310/260, 310/270, 310216114-216118, 310400-433
• US Class Current: 310/410
• CPC Class Codes: H02K 11/25 Devices for sensing temperature, or actuated thereby
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 3/345 between conductor and core, e.g. slot insulation
• CPC Class Codes: H02K 3/38 around winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02K 3/50 Fastening of winding heads, equalising connectors, or connections thereto
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine

Abstract

An objective is to provide a motor stator that may achieve: a reduction in parts costs by shaping coil ends so that length thereof is reduced, thereby reducing the amount of use of copper, and minimizing the amount of use of binding strings for securing the coil ends in place; a reduction in manufacturing process costs by a structure which allows a protector and a wire lead outlet part to be easily assembled; and then an improvement in quality of a stator by firmly holding the coil ends and the protector. The motor stator may include a stator core 1 including slots; a plurality of cut surfaces forming flat surfaces on the outer surface of the stator core 1; end surface insulating plates 2 formed in an approximately same shape as the shape of magnetic steel plates punched out, and assembled into the stator core 1 on both axial end surfaces thereof; projections formed in a vicinity of a peripheral portion of an end surface insulating plate 2, and engaged with the cut surfaces on the stator core 1; slot-like cutouts, a little larger in size than the slots, formed on an inner peripheral side of the each end surface insulating plate 1; and coil ends. The coil ends are shaped by pressure against the end surface insulating plates 2.

Claims

1. A method of manufacturing a motor stator, comprising:

punching in a predetermined shape and layering in an axial direction magnetic steel plates to form a stator core, the stator core including an inner surface on an inside of the stator core and an outer surface on an outside of the stator core, the outer surface provided radially outward from the inner surface, the stator core including on the inner surface a plurality of slots to hold coils,

forming a plurality of cut surfaces on the outer surface of the stator core in the axial direction to provide flat surfaces on the outer surface, the plurality of cut surfaces spaced apart from one another by a predetermined distance along a circumferential direction;

molding a thermoplastic resin into end surface insulating plates, each end surface insulating plate formed to be larger in outer diameter than the stator core and formed to be in an approximately same shape as the predetermined shape of the magnetic steel plates punched out to form the stator core;

forming a plurality of projections in a vicinity of a peripheral portion of each end surface insulating plate, the plurality of projections extending beyond respective end surface insulating plates in the axial direction;

forming slot-like cutouts on an inner peripheral side of each end surface insulating plate, the slot-like cutouts being larger in size than the slots of the stator core, the inner peripheral side being radially inward from an outer peripheral side of each end surface insulating plate;

assembling two of the end surface insulating plates on respective axial end surfaces of the stator core so that the plurality of projections engage with the cut surfaces on the outer surface of the stator core, and in parallel, producing slot cells;

inserting the slot cells into the stator core, and in parallel, producing coils and wedges;

inserting the coils and the wedges into the stator core at a time with an aid of a jig for coil insertion;

shaping coil ends, which are portions of the coils extending out of both axial end surfaces of the stator core in the axial direction, by pressure against the end surface insulating plates, and in parallel, molding the thermoplastic resin into a first protector protecting part and a second protector protecting part;

connecting wire leads to end portions of the coils, and in parallel, placing a protector inside a hollowed out space of the first protector protecting part, and assembling the second protector protecting part into the first protector protecting part;

assembling the protector protecting part holding the protector into the stator, engaging the protector protecting part with a predetermined mounting hole formed on an end surface insulating plate, and binding the protector protecting parts to the coil end;

securing the coil ends in place by a binding string, and in parallel, molding the thermoplastic resin into a first wire lead outlet part and a second wire lead outlet part;

assembling the wire lead outlet part into the stator;

molding the stator to form a molded stator, and in parallel, producing brackets and a rotor assembly; and

assembling the molded stator, the rotor assembly, and the brackets together to have an assembly of a motor.

2. A motor stator comprising:

a stator core that is formed by layering magnetic steel plates punched into a predetermined shape, the stator core including a plurality of slots to hold coils;

a plurality of cut surfaces that are formed on an outer surface of the stator core in an axial direction to provide flat surfaces on the outer surface, the plurality of cut surfaces spaced apart from one another by a predetermined distance along a circumferential direction;

end surface insulating plates that are assembled into the stator core on respective axial end surfaces of the stator core, each end surface insulating plate being larger in outer diameter than the stator core, and formed in an approximately same shape as the predetermined shape of the magnetic steel plates punched out to form the stator core;

a plurality of projections that vertically extend in a vicinity of a peripheral portion of each end surface insulating plate, the plurality of projections being engaged with the cut surfaces on the stator core when the end surface insulating plates are assembled into the stator core;

slot-like cutouts that are larger in size than the slots of the stator core, and formed on an inner peripheral side of each end surface insulating plate; and

coil ends, which are portions of the coils, extending out of both axial end surfaces of the stator core in the axial direction,

wherein the coil ends are shaped by pressure against the end surface insulating plates, and

wherein each end surface insulating plate includes a plurality of string catch notches formed on an outer peripheral edge thereof to hold binding strings to secure the coil ends in place.

3. The motor stator according to claim 2, wherein the motor stator is held by a stator holding portion of a mold die via the end surface insulating plates while the motor stator is molded, thereby preventing the stator core from being exposed after the motor stator is molded.

4. A motor that utilizes a motor stator according to claim 2.

5. A pump that includes a motor according to claim 4.

6. The motor stator according to claim 2, wherein the coil ends extend out of both axial end surfaces of the end surface insulating plates in the axial direction.

7. A motor stator comprising:

a stator core that is formed by layering magnetic steel plates punched into a predetermined shape, the stator core including a plurality of slots to hold coils;

a plurality of cut surfaces that are formed on an outer surface of the stator core in an axial direction to provide flat surfaces on the outer surface, the plurality of cut surfaces spaced apart from one another by a predetermined distance along a circumferential direction;

end surface insulating plates that are assembled into the stator core on respective axial end surfaces of the stator core, each end surface insulating plate being larger in outer diameter than the stator core, and formed in an approximately same shape as the predetermined shape of the magnetic steel plates punched out to form the stator core;

a plurality of projections that vertically extend in a vicinity of a peripheral portion of each end surface insulating plate, the plurality of projections being engaged with the cut surfaces on the stator core when the end surface insulating plates are assembled into the stator core;

slot-like cutouts that are larger in size than the slots of the stator core, and formed on an inner peripheral side of each end surface insulating plate;

coil ends, which are portions of the coils, extending out of both axial end surfaces of the stator core in the axial direction, wherein the coil ends are shaped by pressure against the end surface insulating plates; and

a wire lead outlet part that sandwiches wire leads to be connected to end portions of the coils, and is assembled into one of the end surface insulating plates, the wire lead outlet part including a first nail for assembly,

wherein each end surface insulating plate includes a plurality of wire lead outlet part mounting holes that are provided to be engaged with the first nail of the wire lead output part in the vicinity of the peripheral portion.

8. A motor that utilizes a motor stator according to claim 7.

9. A pump that includes a motor according to claim 8.

10. A motor stator comprising:

a stator core that is formed by layering magnetic steel plates punched into a predetermined shape, the stator core including a plurality of slots to hold coils;

a plurality of cut surfaces that are formed on an outer surface of the stator core in an axial direction to provide flat surfaces on the outer surface, the plurality of cut surfaces spaced apart from one another by a predetermined distance along a circumferential direction;

end surface insulating plates that are assembled into the stator core on respective axial end surfaces of the stator core, each end surface insulating plate being larger in outer diameter than the stator core, and formed in an approximately same shape as the predetermined shape of the magnetic steel plates punched out to form the stator core;

a plurality of projections that vertically extend in a vicinity of a peripheral portion of each end surface insulating plate, the plurality of projections being engaged with the cut surfaces on the stator core when the end surface insulating plates are assembled into the stator core;

slot-like cutouts that are larger in size than the slots of the stator core, and formed on an inner peripheral side of each end surface insulating plate;

coil ends, which are portions of the coils, extending out of both axial end surfaces of the stator core in the axial direction, wherein the coil ends are shaped by pressure against the end surface insulating plates; and

a protector protecting part that holds a protector for cutting off an electric current when the coils reach a predetermined temperature, and is assembled into one of the end surface insulating plates, the protector protecting part including a nail for assembly,

wherein each end surface insulating plate includes a plurality of protector protecting part mounting holes that are provided to be engaged with the nail of the protector protecting part in the vicinity of the peripheral portion.

11. The motor stator according to claim 10, wherein the protector protecting part includes in the vicinity of the peripheral portion thereof protector protecting part string grooves for fixing, and the protector protecting part is bound to a coil end via the protector protecting part string grooves.

12. A motor that utilizes a motor stator according to claim 10.

13. A pump that includes a motor according to claim 12.