US 11,888,347 B2
Core, stator, and rotary electric machine
Tatsuya Saito, Osaka (JP); and Tomoyuki Ueno, Osaka (JP)
Assigned to SUMITOMO ELECTRIC INDUSTRIES, LTD., Osaka (JP); and SUMITOMO ELECTRIC SINTERED ALLOY, LTD., Takahashi (JP)
Appl. No. 17/281,992
Filed by Sumitomo Electric Industries, Ltd., Osaka (JP); and Sumitomo Electric Sintered Alloy, Ltd., Takahashi (JP)
PCT Filed Oct. 17, 2019, PCT No. PCT/JP2019/040974
§ 371(c)(1), (2) Date Apr. 1, 2021,
PCT Pub. No. WO2020/116038, PCT Pub. Date Jun. 11, 2020.
Claims priority of application No. 2018-228584 (JP), filed on Dec. 5, 2018.
Prior Publication US 2021/0344238 A1, Nov. 4, 2021
Int. Cl. H02K 1/14 (2006.01); H02K 1/02 (2006.01); H02K 21/24 (2006.01)
CPC H02K 1/146 (2013.01) [H02K 1/02 (2013.01); H02K 21/24 (2013.01)] 15 Claims
OG exemplary drawing
 
1. A core for use in an axial-gap rotary electric machine, wherein the core is annular and comprises a plurality of core pieces into which the core is divided in a circumferential direction, wherein each core piece includes a yoke portion, and a tooth portion that is formed integrally with the yoke portion and that projects from the yoke portion in an axial direction, wherein each yoke portion includes a plurality of protrusions provided on one side surface that is connected to the yoke portion of an adjacent one of the core pieces, and a plurality of recesses provided on other side surface that is connected to the yoke portion of another adjacent one of the core pieces, the recesses corresponding to the protrusions, and wherein an interval between the protrusions is 80% or less of a length of the one side surface of the yoke portion, the length being a direct distance between inner and outer peripheries of the yoke portion, wherein, in plan view of each yoke portion from a side toward which the tooth portion projects, a distance from the recesses to a bottom of the tooth portion is 20% or more of a distance from a reference line to the bottom of the tooth portion, the reference line being a middle line between a side surface of the tooth portion and a side surface of the tooth portion of the other adjacent one of the core pieces, the side surfaces facing each other.