| 摘要 |
<p>PURPOSE:To obtain a welding point detection apparatus capable of stably detecting a welding point even with respect to a welding point subjected to rolling processing, by automatically altering the setting of a filter by the elongation of a welded part by rolling processing. CONSTITUTION:The frequency of a welded point signal is set by a variable filter 31 and only the welded point signal is extracted by a delay circuit 32, a multiplier 33 and a low pass filter 34 constituting a correlation filter. A filtering setting part 40 determines the control voltage 45 of the filter from the elongation 41 of a steel plate and speed voltage 42, obtained by detecting the speed of the steel plate by a speed detector 22, through a divider circuit 43 and a gain control circuit 44. A delay circuit 33 is constituted so as to shorten a delay time in inverse proportion to control voltage. By this constitution, because even a welded part after rolling can be accurately detected, the tracking of the welded part is enabled without providing a punched hole to the welded part.</p> |
