DEVICE FOR DETECTING SECTIONAL SHAPE OF SHOULDER PART OF WELDING GROOVE AND CENTRAL POSITION OF GROOVE

摘要

PURPOSE:To detect the sectional shape and central position of a groove by subjecting the signal obtd. by converting photoelectrically the optical cut image of a groove part to a differential operation of second order and deciding the shape and position of the groove shoulder from the combination of positive and negative signal waveforms and the max. position thereof. CONSTITUTION:The optical cut image obtd. by the linear light irradiated to a groove part is picked up and is converted to an electrical signal corresponding to reflection luminance. The optical cut line obtd. from said electrical signal is subjected to a differential operation of second order at a wide differential width and the differential operation of second order at the narrow differential width is carried out in accordance with the data obtd. in such a way. The shape of the groove shoulder is decided by the combination of the positive and negative signal waveforms exceeding the respectively specified threshold levels of the output signals from the above-mentioned two second- order differential circuits and at the same time the max. position of the signal waveform is detected as the position of the groove shoulder. The sectional shape and central position of the groove are calculated in accordance with the result of said detection. The sectional shape and central position of th groove where the shoulder part of the groove is hidden or crushed are thus detected.