Abstract:
In order to detect can weld side-seam flaws or defects an infrared sensitive detector head is used. A collimator fiber optics or an optical mask are used to give a higher resolution. Optical fibers may have a second coating of EMA or an occasional optically absorbent fiber may be placed parallel to the optic fibers in order to cut down crosstalk and introduce an absorbent medium between the fibers. Coherent fiber optics may be used.
Abstract:
An electronic circuit for receiving the output of one or more detector units which may pick up the infrared emission from a welded seam as it passes by the detector unit or units. The circuit sorts out high and low signals to give an indication of hot or cold spots which indicate deficient welding. The signal is used to operate indicators, counters, and a weld reject mechanism or marking means.