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:
Nov. 07, 1989
Filed:
Apr. 06, 1988
Applicant:
Inventor:
Alexander Gausa, Bielefeld, DE;
Assignee:
Feldmuehle Aktiengesellschaft, Duesseldorf, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21F / ;
U.S. Cl.
CPC ...
162198 ; 162110 ; 162140 ; 250571 ; 250572 ; 356429 ; 356430 ; 356431 ;
Abstract
A method of testing security papers with respect to the positions of a safety thread and water marks to detect errors in the paper is performed by a linewise scanning of a finished paper web. The web has at least two point like measuring marks inserted into it in addition to the water marks, whereby impulses which are originated from these measuring marks are evaluated and the sheet width and the sheet distortion are calculated by comparing the x-y positions of the individual measuring marks with each other. The measuring marks are sharpe edged and rich in contrast. The given edge impulse is evaluated.