| 摘要 |
PROBLEM TO BE SOLVED: To provide a brushless motor (50) that prevents reduction in bearing lifetime that would not deteriorate rotation unevenness, nor generate large vibrations, and without increasing lateral-pressure current, even if a back yoke is fixed to a bearing holder by caulking. SOLUTION: The brushless motor is provided with a shaft (25), first/second bearings (22, 23) that support both ends of the shaft respectively, a U-shaped bearing holder (10) that has first/second arm parts (10a, 10b) to which the first/second bearings are respectively fixed and a base part (10c) for connecting the first/second arm parts with each other, and a back yoke (20) that is caulked and fixed to the outside face (10a2) of the first arm part perpendicularly to the axis. The inside face (10a3) of the first arm part and the inside face (10b2), facing the inside face (10a3), of the second arm part are faces that are farther apart from each other, being separated from the base part. An angleβ1 formed by the inside face (10a3) and an orthogonal plane orthogonal to the axis and an angleβ2 formed by the inside face (10b2) and the orthogonal plane are set such thatβ1<β2. COPYRIGHT: (C)2009,JPO&INPIT |
