Patent ID: 8803390

Claim:
A dynamo-electric machine comprising: a casing that includes: a first housing portion that supports a first ball bearing and includes an engaging part; and a second housing portion that supports a second ball bearing and includes an engaging part, wherein the engaging part of the second housing portion is axially snap-fitted to the engaging part of the first housing portion to couple the second housing portion to one end part of the first housing portion; a plurality of permanent magnets that are fixed to an inner peripheral surface of the first housing portion and are spaced from one after another in a circumferential direction; an armature that is rotatably placed radially inward of the plurality of permanent magnets and includes a rotatable shaft, the rotatable shaft being rotatably supported by the first ball bearing and the second ball bearing; and a resilient urging member that is axially positioned between the second ball bearing and a support wall of the second housing portion to exert an axial urging force, wherein: the axial urging force of the resilient urging member urges the second ball bearing and the support wall of the second housing portion axially away from each other; the axial urging force of the resilient urging member axially urges the second ball bearing together with the rotatable shaft and the first ball bearing away from the support wall, and the axial urging force of the resilient urging member axially urges the first housing portion away from the second housing portion through the first ball bearing; and an engaging surface of the engaging part of the first housing portion is axially urged against an engaging surface of the engaging part of the second housing portion by the axial urging force of the resilient urging member conducted to the first housing portion through the first ball bearing.