US 11,888,351 B2
Core, stator, and rotary electric machine
Tatsuya Saito, Osaka (JP); Yuichi Nakamura, 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. 17/278,333
Filed by Sumitomo Electric Industries, Ltd., Osaka (JP); and Sumitomo Electric Sintered Alloy, Ltd., Takahashi (JP)
PCT Filed Sep. 5, 2019, PCT No. PCT/JP2019/035081
§ 371(c)(1), (2) Date Mar. 22, 2021,
PCT Pub. No. WO2020/100385, PCT Pub. Date May 22, 2020.
Claims priority of application No. 2018-212322 (JP), filed on Nov. 12, 2018.
Prior Publication US 2021/0351639 A1, Nov. 11, 2021
Int. Cl. H02K 1/14 (2006.01); H02K 1/18 (2006.01)
CPC H02K 1/182 (2013.01) [H02K 1/148 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A core that is used in an axial-gap rotary electric machine, comprising:
a body; and
frame-shaped flange portions,
wherein the body includes an annular yoke and columnar teeth that are arranged in a circumferential direction of the yoke,
wherein the flange portions are fixed to end portions of the respective teeth,
wherein the yoke and the teeth are composed of a single powder compact,
wherein each of the flange portions is composed of a powder compact that has a through-hole,
wherein the end portion of each of the teeth is inserted in the through-hole, and an end surface of each of the teeth is exposed from the through-hole,
wherein a ratio of a first area of the end surface of each of the teeth to a second area within an outer circumferential edge of each of the flange portions is 7.5% or more in a plan view in an axial direction of the yoke, and the second area includes an area of the through-hole,
wherein the teeth have step portions on which the flange portions are placed,
wherein each of the step portions includes a bottom surface, which is a flat surface parallel to the end surface, and a circumferential surface,
wherein each of the flange portions includes a lower surface that is placed on the bottom surface, and
wherein the lower surface protrudes from the bottom surface in a direction perpendicular to the circumferential direction and the axial direction,
wherein heights of the step portions are equal to or more than thicknesses of the flange portions,
wherein a difference between the heights of the step portions and the thicknesses of the flange portions are more than 0 mm and no more than 3 mm,
wherein the end portion of each of the teeth has an inclined surface that intersects the end surface of the tooth, and
wherein an angle formed by the inclined surface with respect to an extension surface from the end surface is no less than 5° and no more than 60°.