Method for measurement of the distance between a component which is moved past a reference surface and that reference surface, and a measurement system for carrying out the method

摘要

A method for measurement of the distance between a component which is moved past a reference surface and that reference surface is intended to be suitable in particular for use for the measurement of radial gaps in a turbine, while having particularly high measurement accuracy. To this end, a method based on a triangulation measurement be combined with a reference measurement for determination of the actual speed of the component. In this case, two light beams aligned essentially parallel to one another as well as at least one further light beam, aligned at an angle to the parallel light beams in the movement direction of the component, are monitored for a respectively associated reflection signal which is caused by the component. The time difference between the arrival of the reflection signals associated with the parallel light beams on the one hand, and the time difference between the arrival of the reflection signals associated with one of the parallel light beams and the angled light beam on the other hand, are used to determine a characteristic value for the distance.