The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 17, 1987
Filed:
Jun. 28, 1984
Michael R Croset, Hampshire, GB;
Martin Lane, Hampshire, GB;
De La Rue Systems Limited, London, GB;
Abstract
Apparatus for sensing the passage of sheets (48) through a nip (24), comprises a pair of guide surfaces (20,27) defining the nip (24); means (17,20) for passing sheets (48) through the nip (24); and sensing means formed by pairs of light emitting diodes (37) and phototransistors (38) (37,38) for sensing the deflection of one guide surface relatively to the other. Monitoring means (41,42,43) are provided for monitoring the output of the sensing means (37,38) and for storing a guide surface profile corresponding to the sensing means output when no sheet (48) is present. Comparison means (44) compares subsequent test profiles generated by the monitoring means (41,42) with the stored profile; and detection means (42) detects the presence of a sheet in the nip (24) only when there is a substantially uniform difference between the stored and test profiles.