DETECTING METHOD FOR SPARK ON BRUSH SLIDE SECTION AND ROUGHNESS ON COMMUTATOR FACE IN MOTOR AND THE LIKE

摘要

PURPOSE:To monitor the spark generation state on all brushes by detecting the generation of sparks based on the sliding sound of brushes detected by an AE sensor fitted to a bearing. CONSTITUTION:An AE(acoustic emission) sensor 11 is installed on the bearing of a DC motor or in the space near the bearing, and the sound generated by the motor is detected by the sensor 11 and transmitted to a signal processing unit 12. The signal processing unit 12 converts the inputted sound into the AE wave-form and feeds it to the spectrum analyzer 15 of a data processing unit 12. The spectrum analyzer 15 analyzes the frequency of the AE wave-form, and an alarm is generated from an alarm unit 17 by the output signal from the data processing unit 14 when the AE level of the rotation frequency exceeds the threshold value set in a microcomputer 16. The spark generation state on all brushes can be monitored, and defective positions generating sparks are never overlooked.