| 摘要 |
PURPOSE:To decide accurately whether chamfering is defective or not, by detecting the distance between the screw cut track and the tube end and by comparing the detected minimum value with the decision reference value set preliminarily. CONSTITUTION:The light from projector 4 is irradiated to end part 2 of tube 1 with screw, and the light reflected by the chamfering part of end part 2 reaches the free-scanning type photodetector, and the electric signal converted by this photodetector reaches nochamber deciding circuit 6. When nochamfer is decided by said deciding circuit 6, this decision signal is supplied to marking device 7, and the paint indicating that tube 1 with screw is defective is sprayed from marking device 7 to tube 1 with screw. Said deciding circuit 6 detects the distance between the screw cut track and the tube end, and the detected minimum value is compared with the predetermined decision reference value, thereby deciding whether chamfering on the outside face is defective or not. |
