VISUAL INSPECTION APPARATUS OF PIPE

PROBLEM TO BE SOLVED: To provide a visual inspection apparatus capable of properly detecting defects in appearance of shape, such as, irregular shape and concave shape formed on the outer circumference surface of a tube. SOLUTION: The visual inspection apparatus 1 includes an illumination device 3 for irradiating a uniform diffused light to the outer circumference surface of the tube 10, and a camera 41 for taking a grayscale image of shade formed on the outer circumference of the tube 10 by the irradiation of the diffused light. Also, the camera 41 is arranged so that the optical axis Oc is oblique with respect to the axis line Ot of the tube 10. In the tube 10, irregular shape and concave shape may be formed on the outer circumference surface in the production process. When the uniform diffused light is irradiated to the outer circumference surface of the tube 10, grayscale shade of irregular shape or concave shape is formed on the surface irradiated. By imaging the outer circumference surface of the tube 10 by the camera 41, a clear image of the grayscale shade formed by the irradiation of the diffused light is obtained. COPYRIGHT: (C)2011,JPO&INPIT