| 摘要 |
<p>PURPOSE:To detect an automatic and highly efficient detection of an ink marked part with no malfunction in the consecutive manufacturing process of a long-size tube material of the wire, by receiving and detecting the irregularly reflected beams at the marked part by at least one of photodetectors to projectors. CONSTITUTION:The beams are irradiated intermittently to a travelling tube material of the wire 8 from projectors 2, 4 and 6 set at the 1st position. That is, the irregularly reflected beams are made incident to photodetectors 12, 14 and 16 set at the 2nd position by projecting beams alternately in an extremely short time and in order of projectors 2, 4 and 6. The irregularly reflected beam is delivered to a length deciding circuit 38 from a discriminating circuit only in case the reflected beam is higher than a prescribed level. The circuit 38 delivers a detecting signal only when an output has a continuous change longer than a prescribed period of time. Then a defect eliminating device is actuated on the basis of the detecting signal.</p> |
