| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for detecting abnormality such as a deformed sheet mixed with a plurality of folding processed sheets, on the basis of change in a shape of the end folded part.SOLUTION: A method for detecting abnormality in folding processed sheets includes the steps of: aligning a plurality of folding processed sheets 1; radiating light to generate bright parts 5 on the backs of the sheets and shadow parts 6 at crevices between the sheet backs; imaging the bright parts 5 and the shadow parts 6 by a television camera 7; converting captured image signals into signals of color intensity multivalued for every color by an analog-digital conversion circuit 9; comparing the color intensity of every composition point composing one horizontal scan line with reference values of a sheet reference line; estimating a signal of the color intensity of each composition point as one non-shadow part when the color intensity of the composition point becomes greater than the reference value and then becomes smaller than the lower reference value; repeating the comparison processing until another end of the aligned sheets; calculating an area of the sheets on the basis of composition points of which color intensity is greater than the reference value of the sheet reference line; and comparing the calculated area with an average area or a normal sheets area to detect abnormality. |
