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. 13, 1993
Filed:
Sep. 25, 1991
Daniel W Mayer, Arden Hills, MN (US);
Roger C Oestreich, River Falls, WI (US);
Richard Rosik, Minneapolis, MN (US);
Modern Controls, Inc., Minneapolis, MN (US);
Abstract
A process and apparatus for controlling the thickness of film made in a blown film machine having a rotating die, wherein a variable speed motor is used to control the haul-off speed of the film from the machine, by subdividing the die rotation into angular segments, measuring the blown film thickness at a point fixed in space and across each of the angular segments, and calculating an average film thickness for an angular segment, and comparing the measured thickness against a preselected desired thickness, and increasing or decreasing the speed of the variable speed motor to change the haul-off speed to bring the measured thickness into agreement with the preselected thickness.