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:
May. 12, 1992
Filed:
Mar. 28, 1990
Eric J Reber, Rockford, IL (US);
Barber-Colman Company, Rockford, IL (US);
Abstract
A non-contact caliper-type gauge particularly suited for measuring the thickness of a running web. In its preferred form, the system includes a pair of opposed scanning heads defining a gap through which the running web passes, the heads being adapted to transverse across the width of the running web. Each of the heads includes and ultrasonic transducer for directing energy at the web, detecting energy reflected from the face of the web nearest the respective transducer and determining the distance between a reference in the head and the facing surface of the web. One of the heads also includes a transducer, preferably an eddy current transducer, which operates on energy to which the web is transparent. The second transducer senses the distance between the heads thereby to determine any variations in the distance between the heads during traverse. The distances determined by each of the ultrasonic transducers to the respective surfaces of the web are subtracted from the total gap distance to produce a corrected measure of web thickness which is substantially independent of mechanical variations in gap between the heads.