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:
Sep. 14, 1999
Filed:
Aug. 05, 1997
Klemens Sensen, Lengerich, DE;
Ansgar Avermeyer, Georgsmarienhutte, DE;
Windmoller & Holscher, Lengerich/Westf, DE;
Abstract
To control the film thickness in a blown film extrusion line with reversing or rotating takeoff of the film bubble, the thickness profile of the blown film bubble is measured over its circumference. Different temperatures can be applied to sections of the film bubble by a die ring divided into heating sections provided with control elements or by heating elements, forming a ring around the extruded film bubble and provided with control elements. In order to correctly assign the position of the measured thickness profile to the heating sections of the die ring or the heating elements, the extruded film bubble is provided with a mark in the region of the die ring or the heating elements and the rotation of this mark is measured by a measuring device at specified intervals from the die ring or the heating elements.