CN-115483772-B - Stator core, rotary electric machine, and drive device

Abstract

The invention provides a stator core, a rotating electrical machine, and a driving device. The stator core is a stator core in which a plurality of steel plates are laminated, and includes an annular core back centered on a central axis, and a plurality of pole teeth extending radially from the core back, and a radially facing side surface of the core back is provided with a plurality of welded portions extending in an axial direction and fixing the plurality of steel plates to each other, and groove portions extending in the axial direction. The plurality of welding parts include a first welding part, a second welding part and a third welding part which are sequentially arranged along the circumferential direction. The angle formed by the central axis, the first welding portion and the second welding portion is larger than the angle formed by the central axis, the second welding portion and the third welding portion, and the groove portion is arranged between the first welding portion and the second welding portion adjacent to each other in the circumferential direction.

Inventors

• SUGAYA KOJI
• TAKAYAMA SHOGO

Assignees

• 日本电产株式会社

Dates

Publication Date

20260505

Application Date

20220513

Priority Date

20210531

Claims (8)

1. 1. A stator core, which is a stator core in which a plurality of steel plates are laminated, comprising: an annular core back centered on the central axis, and A plurality of teeth extending radially from the core back, The radially facing side of the core back is provided with: a plurality of welded portions extending in an axial direction and fixing the plurality of steel plates to each other, and A groove portion extending in an axial direction, The plurality of welding parts comprise a first welding part, a second welding part and a third welding part which are sequentially arranged along the circumferential direction, The angle formed by the central axis, the first welding part and the second welding part is larger than the angle formed by the central axis, the second welding part and the third welding part, The groove portion is arranged between the first welding portion and the second welding portion adjacent in the circumferential direction, The stator core has a plurality of blocks stacked in a thickness direction, and groove portions included in different blocks are arranged at equal intervals in a circumferential direction.
2. 2. The stator core according to claim 1, wherein, The groove portion is disposed on a bisector of an angle formed by the central axis, the first welded portion, and the second welded portion.
3. 3. The stator core according to claim 1 or 2, wherein, A plurality of the steel plates are rotationally laminated at a rotational lamination angle, The angle formed by the central axis, the first welding part and the third welding part is equal to the rotation lamination angle.
4. 4. The stator core according to claim 1 or 2, wherein, The welding portion or the groove portion is arranged on a center line of the pole tooth when viewed in the axial direction.
5. 5. The stator core according to claim 1 or 2, wherein, The welding portion or the groove portion is arranged on a center line of a groove between the adjacent pole teeth when viewed in the axial direction.
6. 6. The stator core according to claim 1 or 2, wherein, Grooves are arranged between the circumferentially adjacent pole teeth, The plurality of slots includes a first slot and a second slot for passing coil wires of different phases, The groove portion is disposed between a center line of the first groove and a center line of the second groove when viewed in the axial direction.
7. 7. A rotating electrical machine, comprising: A stator having the stator core as claimed in any one of claims 1 to 6, and A rotor that is relatively rotatable with respect to the stator.
8. 8. A driving apparatus comprising: A rotary electric machine as recited in claim 7, and And the transmission device is connected with the rotor.

Description

Stator core, rotary electric machine, and drive device Technical Field The invention relates to a stator core, a rotating electrical machine, and a driving device. Background As a stator core of a rotating electrical machine, a structure in which a plurality of electromagnetic steel plates are laminated is known. In this case, the stacked steel plates are fixed to each other by welding the peripheral edges. Patent document 1 discloses a structure in which welded portions are arranged at equal intervals on the outer peripheral surface of a stator core. Prior art literature Patent literature Patent document 1, japanese patent application laid-open No. 2010-268603. Disclosure of Invention However, since the magnetic flux also flows through the core back portion of the stator core, when the stator core is fixed by welding, the magnetic circuit is affected, and torque ripple may be deteriorated. Therefore, a structure capable of reducing torque ripple while fixing the stator core (steel plate) is demanded. In view of the above, an object of the present invention is to provide a stator core, a rotary electric machine, and a driving device capable of reducing torque ripple. One embodiment of the stator core of the present invention is a stator core in which a plurality of steel plates are laminated. The stator core includes an annular core back centered about a central axis and a plurality of pole teeth extending radially from the core back. The radially facing side of the core back is provided with a plurality of welded portions that extend in the axial direction and fix the plurality of steel plates to each other, and groove portions that extend in the axial direction. The plurality of welding parts comprise a first welding part, a second welding part and a third welding part which are sequentially arranged along the circumferential direction. The angle formed by the central axis, the first welding portion and the second welding portion is larger than the angle formed by the central axis, the second welding portion and the third welding portion. The groove portion is disposed between the first welded portion and the second welded portion adjacent in the circumferential direction. One embodiment of the rotating electrical machine of the present invention includes a stator having the stator core described above, and a rotor that is rotatable relative to the stator. One embodiment of the drive device of the present invention includes the rotating electrical machine described above, and a transmission device connected to the rotor. According to one embodiment of the present invention, a stator core, a rotating electrical machine, and a driving device that can reduce torque ripple can be provided. Drawings Fig. 1 is a schematic diagram of a driving device according to an embodiment. Fig. 2 is an exploded perspective view of a stator core of an embodiment. Fig. 3 is a perspective view of a stator core of an embodiment. Fig. 4 is a top view of a stator core of an embodiment. Fig. 5 is a plan view showing a part of fig. 4 in an enlarged manner. Fig. 6 is a partially enlarged view of a stator core of a modification. Fig. 7 is a partially enlarged view of a stator core of a modification. Fig. 8 is a graph showing a simulation result of torque fluctuation in the above embodiment. (Symbol description) 10 Rotor, 30 rotor, 40 stator, 42 coil, 43 coil wire, 43U, 43V, 43W coil wire, 70 stator core, 71 core back, 72 pole tooth, 75 positioning slot (slot), 76 weld, 76A first weld, 76B second weld, 76C third weld, 79 plate, 100 drive, J center axis, L bisector, S slot, S2V phase slot (first slot), S3W phase slot (second slot), SL slot center line (center line), TL pole tooth center line (center line) Detailed Description Hereinafter, embodiments to which the present invention is applied will be described in detail with reference to the accompanying drawings. In the drawings used in the following description, for the purpose of emphasizing a characteristic portion, the portion to be a characteristic is shown enlarged for convenience, and the dimensional ratios and the like of the respective constituent elements are not necessarily the same as those of the actual ones. For the same purpose, portions not serving as features may be omitted. Fig. 1 is a schematic diagram of a driving device 100 according to the present embodiment. The drive device 100 is a drive device that is mounted on the vehicle and rotates the axle 64. The vehicle mounted with the drive device 100 is a motor-powered vehicle such as a Hybrid Electric Vehicle (HEV), a plug-in hybrid electric vehicle (PHV), or an Electric Vehicle (EV). As shown in fig. 1, the driving device 100 includes a rotary electric machine 10 and a transmission device 60. The transmission device 60 is connected to the rotating electrical machine 10, and transmits rotation of the rotating electrical machine 10, that is, rotation of a rotor 30 described later, to an axle 64 of the vehicle. The tr