| 摘要 |
PURPOSE:To completely scan the overall length of the outside peripheral surface to be inspected of a cylindrical body without excess and shortage by giving an incident angle to the peripheral surface to be inspected and projecting a flat beam whose width is wider than length of the peripheral surface to be inspected in parallel to the rotation axis. CONSTITUTION:A cylindrical body W to be inspected is rotated by a rotation supporting device 1. The peripheral surface to be inspected is irradiated by a flat beam whose width is longer than length of the peripheral surface to be inspected at an incident angle in parallel to the rotation axis from a projecting part 2, and the whole surface of the peripheral surface is scanned. The irradiating light is reflected by the peripheral surface to be inspected, but both an irregularly reflected light from a flaw part and an irregularly reflected light from the outside of the peripheral surface to be inspected are received by a light receiving part 3, and a regularly reflected light is received by a light receiving part 4. A signal from the light receiving part 3 is brought to gate by AND with a signal from the flight receiving part 4, inputted to a width measuring part 11 after an irregularly reflected light signal from the outside of the outside peripheral surface to be inspected has been eliminated, and compared with a prescribed width value. When that which exceeds the prescribed width exists, its width is integrated successively by an integrator 12. |
