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. 19, 1977
Filed:
Mar. 25, 1975
Applicant:
Inventors:
John M Lucas, Montreal, CA;
Serge Gracovetsky, St. Lambert, CA;
Assignee:
Domtar Limited, Montreal, CA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N / ; G01B / ; G01N / ;
U.S. Cl.
CPC ...
250562 ; 250572 ; 356120 ; 356199 ; 356209 ;
Abstract
The invention is concerned with measuring 'on-line' the surface roughness of a moving sheet material, e.g. a paper web. The method comprises illuminating the moving web, preferably at a low angle, suitably collecting the light reflected from the moving web and processing the light by means of a sensitive photo-electrical system. The electrical signals thus obtained are divided into an AC and a DC component, the components are separately measured and their ratio used as an index of roughness. An apparatus for carrying out roughness measurements on a moving paper web, e.g. on a paper machine, is described.