Patent ID: 6193423
Filing Date: 2001-02-27
Classification: G03D

Abstract:
A device for monitoring a sheet material as said sheet material is conveyed along a prescribed conveying path, said device comprising:a photoelectric conversion element which has a linear detecting area and outputs a value which varies in accordance with an amount of light received at the detecting area, the amount of light changing due to the passage of a sheet material along the conveying path; andrecognizing means which recognizes a position of a transverse direction end portion of the sheet material on the basis of a value output by the photoelectric conversion element;wherein the change in the amount of light received at the detecting area due to the passage of the sheet material along the conveying path is caused by the presence or absence, the number and the pitch of perforations formed in the sheet material, and a type of the sheet material is recognized from the presence or absence, the number and the pitch of the perforations.