抄録
Universal motors are used in mainly cleaners. The commutating processes take place by sliding contact of commutator segment and brush, and sparks occur when a segment separates from the brush. The commutation sparks cause wear on the brush and electromagnetic interference to other electronic machines. We visualized images of sparks on high-revolving. motors by a high-speed camera, and analyzed the mechanism of the spark generation. We devised external laser triggering using laser light for shuttering of the camera. This method make it easier to analyze images because it provides with images of the same point of the same segment every time. By photographing spark generation with a high-speed camera by external laser triggering we probed that sparks occurred on every other segment and also visualized that commutation spark occurred on one segment.
