Air gap width monitoring device for use in direct current machine, has receiver detecting laser beam reflected by rotor and/or collector, and connected to evaluating unit for producing disabling signal for machine

摘要

The device has two laser light sources (5) that are arranged at a stator (2) in a regular angle distance and measures the distance between the stator and a rotor (3) and/or a collector surface. A receiver (5`) detects a laser beam reflected by the rotor and/or a collector. The receiver is connected to an evaluating unit for producing a disabling signal for a direct current machine (1).