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:
Apr. 14, 2009
Filed:
Apr. 25, 2006
John Buttifant, West Sussex, GB;
John Alan Skinner, Hampshire, GB;
Peter Dilwyn Evans, Hampshire, GB;
Michael Potter, Hampshire, GB;
Peter Alan Pullan, Hampshire, GB;
Barry Clifford Scowen, Surrey, GB;
John Buttifant, West Sussex, GB;
John Alan Skinner, Hampshire, GB;
Peter Dilwyn Evans, Hampshire, GB;
Michael Potter, Hampshire, GB;
Peter Alan Pullan, Hampshire, GB;
Barry Clifford Scowen, Surrey, GB;
De La Rue International, Ltd., Hampshire, GB;
Abstract
A method of detecting a coded magnetic thread is provided that includes sensing the response of a magnetic field detector as a thread passes the detector, the response varying from an initial magnitude in first and second senses to exhibit a first peak, and then in the first sense to exhibit a second peak; comparing the response with first and second thresholds disposed about the initial magnitude in the first and second senses respectively; and indicating the passage of a code element of the thread when the response passes the second threshold and then the first threshold in a predetermined manner characterized in that the first threshold is adjusted in accordance with a first predetermined algorithm based on the magnitude of the first peak. The first predetermined algorithm adjusts the first threshold so that the magnitude of the first threshold is the average of a predetermined number of preceding first peaks.