| 摘要 |
PURPOSE:To detect flaws continuously and smoothly without reducing the speed to improve the flaw detection efficiency, by controlling the moving speed of a truck and the rotation speed of a round bar in accordance with displacement of a flaw detecting head based on the truck which corresponds to the sectional shape of the round bar. CONSTITUTION:A flaw detecting head 27 brought into contact with a round bar 11 through a contact roller 28 is displaced in accordance with the sectional shape of the round bar 11, and a bracket 25 is turned around a pin 24. The displacement, which is based on a truck 18, of the head 27 which moves as one body together with the truck 18 which is moved linearly through a motor 20 is detected by a displacement detector consisting of a differential transformer 34 and a detecting rod 35. A motor 15 which drives the motor 20 and a rotary roller table 14 is controlled in accordance with this detection value to change properly the linear moving speed of the truck 18 and the turning speed of the round bar 11. Consequently, it is unnecessary to reduce preliminarily the linear moving speed and the turning speed excessively considering the sectional shape of the round bar, and the continuous flaw detection is performed smoothly to improve the flaw detection efficiency. |
