Patent ID: 8218813
Filing Date: 2012-07-10
Classification: B65H

Abstract:
1. A method for detecting if a double feed has occurred or not in a double feed detection system when mail pieces with tabs are conveyed on their edge in a longitudinal direction along a path, comprising the steps of: obtaining a scan of a bottom edge of the mail pieces by locating an electronic line-scan camera below the transport path such that an optical longitudinal axis of the camera is transverse to the transport direction of the mail pieces, whereby said scan is obtained through an aperture in a base plate; comparing the characteristics of the line by line scanned mail piece bottom edge image with those of predetermined sets of characteristics derived from typical samples of bottom edge images in order to determine whether or not a double feed has occurred, characterized by; simultaneously viewing a side of a piece of mail adjacent the bottom edge simultaneously with the bottom edges with a simultaneous viewing means; and processing images produced by the camera and the simultaneous viewing means to identify if the mail piece is a single mail piece with a tab, or if a double feed has occurred.