| 摘要 |
PURPOSE:To detect knife mark flaws generated in the slicing process for generating a thrust plate or the like, by irradiating an examination region on a carrying face for an object to be examined with a pair of beam lights obliquely from above and below and converting photoelectrically reflected lights and comparing them with each other. CONSTITUTION:A light projecting means 14 consisting of a halogen lamp 12 and a cylindrical lens 13 is provided to the obligue reas above the carrying line of a prescribed examination region on a carrying face for an object to be examined, and a light projecting means 14 consisting of a halogen lamp 15 and a cylindrical lens 16 is provided to the obligue rear under this carrying line. A cylindrical lens 18, a slit 19, and a photomultiplier 20 are arranged above the examination region, and a cylindrical lens 21, a slit 22, and a photomultiplier 23 are arranged under the examination region. Output signals of photomultipliers 20 and 23 are inputted to a flaw discriminating circuit 26 consisting of an amplifying circuit 24 and a flaw detection output circuit 25. Thus, since the existence of flaws is detected in a certain level or more, the precision of flaw detection is improved. |
