| 摘要 |
PURPOSE:To detect the moving speed of an object to be carried with high accuracy even in the case of a spiral movement based on the relative speed of an optical sensor to the object to be carried as well as the moving speed of the optical sensor itself, by shifting the optical sensor following the object to be carried. CONSTITUTION:A truck 5 is put on a guide rail 4 which is provided in parallel to the moving direction of a steel pipe 1, and the truck 5 has a reciprocal movement in parallel to the moving direction of the pipe 1 by the drive of a motor M. An optical sensor 8 consisting of a long-size kight emitter 81 and a light receiver 82 are set opposingly to the pipe 1 centering on the rear edge part of the pipe 1 an to an arm erected on the truck 5. Then the truck 5 is moved to give a follow-up movement to the sensor 8 to the pipe 1 in the state under which the relative moving speed is set at zero or at a level under a certain value. Then an arithmetic process is carried out at an arithmetic control part CN based on the moving speed of the sensor 8 itself as well as the relative moving speed of the sensor 8 to the pipe 1. Thus the moving speed of the pipe 1 is detected and displayed to a displayer DP. |
