GB1358813A - Document recognition systems - Google Patents

Abstract

1358813 Examining bank-notes M MARTELLI and M MARTELLI 13 Oct 1972 [15 Oct 1971] 47308/72 Heading G1A In an optical analyzer suitable for checking bank-notes 7a light source 1 and two photosensitive members 5 and 3 are positioned so as to provide output signals representing the transmissivity and reflectivity of a predetermined area of the bank-note 7, the output signals being electronically compared with reference ranges for the transparency and reflectivity of genuine bank-notes to determine the validity of the note. The source 1 is rotatable about its own axis by holder 9 so as to orientate the image of the filament on the bank-note in any desired manner. A plurality of analyzers for simultaneous measurement of several points may be employed. The position of the analyzer may be adjustable Figs. 6, 7, 8 and 9, (not shown), in that the whole analyzer may be incorporated in a support head having a pair of stop pins which can engage a selected one of a plurality of pairs of holes in a base member. The optical analyzer may be included in a detection system for a reading machine that examines, the watermark present in the bank-note (i. e. its transmissivity at that point), the reflection from a printed surface of the bank-note at the different areas, the wire passing through the interior of the bank-note, the type of paper used, the bank-note thickness and the length of the bank-note. An associated control circuit Figs. 10 and 11, (not shown) will then only provide a signal for accepting the banknote and dispensing the merchandise when all the above criteria are satisfactory. In the Fig. 3 embodiment a bank-note is fed via an inlet 29 along a guide 31 thereby triggering an ingress switch 11 (a micro-switch or photoelectric relay) and energizing rollers 17A to feed the bank-note along the guide 31 into the analyzer 15 where it scrutinizes several selected discrete points of the bank-note and provides signals which are processed to determine the bank-notes validity and to activate an electromagnetic switch 33 which will direct the banknote along path 37 (dotted lines) or along path 35, depending upon whether or not the bank-note has been accepted or rejected. The bank-note is stretched while it is being scrutinized because rollers 17B drives the bank-note at greater speed than the first pair. While the bank-note is being examined in the analyzer its presence there, that is, its leading edge, is detected by a reset switch 19 which causes the rollers 41 to be locked preventing further notes from being placed in the machine, while a note is in the analyzer.