Patent ID: 9337698
Filing Date: 2016-05-10
CPC Classification: H02K

Claim Text:
1. A rotating electric machine comprising: a stator; a rotor rotatable disposed within the stator; a casing housing the stator and the rotor; a first frame disposed at one axial end of the casing in an axial direction of the rotor and having a first flange that protrudes outwardly from the casing in a radial direction of the rotor; a second frame disposed at an other axial end of the casing in the axial direction of the rotor to hold the casing together with the first frame and having a second flange that protrudes outwardly from the casing in the radial direction; and a through bolt that is inserted through a through hole provided in the first flange and is attached to the second flange, wherein: the first flange includes a recessed portion that is recessed toward the second flange from a side surface of the first flange that is opposite to the second flange, the recessed portion having a bottom surface as a contact surface for the through bolt; and the recessed portion includes (i) a first wall surface that is positioned on a side opposite to a rotational axis of the rotor with respect to the through hole, (ii) a second wall surface that is positioned on a side close to the rotational axis with respect to the through hole, and (iii) a pair of third wall surfaces that connects the first wall surface and the second wall surface, the first wall surface, the second wall surface, and the pair of the third wall surfaces positioned around the bottom surface of the recessed portion, wherein a virtual line passes through the rotational axis and an axis of the through hole, a first virtual circle is concentric with the rotational axis and passes through the axis of the thorough hole, a first curved portion of a first fillet curve between the first wall surface and the bottom surface is positioned on the virtual line, a second curved portion of a second fillet curve between the second wall surface and the bottom surface is positioned on the virtual line, and a third curved portion of a third fillet curve between each of the pair of the third wall surfaces and the bottom surface is positioned on the first virtual circle, wherein a curvature radius of the third curved portion is greater than a curvature radius of the first curved portion and a curvature radius of the second curved portion.