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:
Feb. 03, 1976
Filed:
Jul. 01, 1974
James N Crum, Stonington, CT (US);
Harris Corporation, Cleveland, OH (US);
Abstract
A web tension control system for a reel stand used with a web-fed printing press in which web material is pulled into the press and unwound from a roll on a reel and having a dancer engaging a loop in the web material intermediate the roll and the press. The dancer applies a constant force to the web material at the loop irrespective of the position of the dancer within its range of travel. The reel is equipped with a friction brake whose retarding torque is controlled by a resultant control signal to which several signals contribute. A first signal contributing to the resultant control signal is proportional to the instantaneous radius of the roll of web material and is produced by digitally dividing the press speed by the angular speed of the reel. A second contributing signal is a negative feedback signal that is proportional both to the computed roll radius and to the dancer position. Torque applied by the brake in response to the resultant signal tends to maintain the dancer in a predetermined central position. When the press is coming to a stop a predetermined web tension is achieved by controlling the brake torque in proportion only to the first signal.