BRUSH WEAR DETECTOR, BRUSH WEAR INDICATOR AND RECTIFIER PROTECTING DEVICE

摘要

PURPOSE:To effectively detect wear of a brush at a suitable time, to easily recognize the wear of the brush and to prevent an increase in damage of a commutator due to the wear of the brush. CONSTITUTION:An insulating plate 5 is provided on the side of a brush holder 21, moving elements 8A (8B, 8C) passing through the plate 5 and the holder 21 are provided, movable side contacts 6A (6B, 6C) are respectively provided at the elements 8A (8B, 8C), and stationary side contacts 9A (9B, 9C) are provided at the plate 5. Signal lamps 11A (11B, 11C) connected to the stationary side contacts are provided at an indicator 2. Further, a time limit relay 12 connected to the contact 9C of a rectifier 14 side and a protective circuit 3 containing a relay 13 are provided to effectively detect wear of a brush at a suitable time, the wear is easily recognized, and an increase in damage of a commutator due to the wear can be prevented.