WELD POSITION SHAPE MEASURING APPARATUS

PURPOSE:To accurately measure the shape of weld position at a high speed without using a memory circuit of large capacity by an apparatus wherein a signal pre-processing section is provided which comprises x- and y-coordinate counters, and arithmetic operation is performed based on x- and y-coordinate addresses obtained in that section. CONSTITUTION:A signal processing section 10 comprises a signal pre-processing section 11 and an arithmetic processing section 12. A video signal from a pickup unit 4 for picking up a slit image, which is formed by irradiating the welded part, is sent to the signal processing section 10 so that the maximum brightness level of the video signal in one horizontal scan is detected by a peak holding circuit 16. An x-address thereof is determined by a position counter 18 and a y- address thereof is determined by a position counter 21, both addresses being sent to the arithmetic processing section 12. Thus, all data required for computing the shape at the completion of 1-frame period of the pickup unit 4 are stored in the memory section, thus enabling to determine the shape of a weld line based on that data.