On-Line Gauge for Wire and Fibre Diameter Measurement

Abstract

A new gauge has recently been developed for on-line measurement of filament diameters in the size range 5–160 microns. The instrument, which operates on a laser diffraction principle, has been designed for non-contacting gauging of wires, filaments and fibres on the production line. It can accept horizontal or vertical wires, and it can readily be moved from one line to another, and used in the laboratory or test bay. The absolute accuracy of measurement attainable is approximately 1% of the diameter of the filament, while the sensitivity of the gauge to changes in diameter is about 0· 2%. The deviation from nominal diameter is displayed on a meter, or can be recorded automatically. It is possible to use the output signal from the instrument in a control mode to correct the diameter of the wire under production.