| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To eliminate a possibility of not being capable of diagnosing whether a brush 18 is deteriorated with high accuracy. <P>SOLUTION: An abnormality diagnosis device for a stator employs a brush 18 configured to have a layer (an abrasion detection part 18a) which lies at a position away from the contacting surface with a commutator 24 toward the brush 18 side and whose material is different from the material of other part (a normal part 18b). Specifically, a ratio of copper to carbon is lower in the abrasion detection part 18a than in the normal part 18b. In this configuration, if a variation of the battery voltageΔV detected during cranking is determined as larger than a prescribed value Vα, a diagnosis to the effect that the brush 18 is deteriorated is to be performed. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
