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:
Jun. 04, 1991
Filed:
May. 01, 1989
Edward S Babson, Ipswich, MA (US);
Thomas G Brophy, Gloucester, MA (US);
Michael R Porter, Topsfield, MA (US);
Porter Sewing Machines, Inc., Beverly, MA (US);
Abstract
A method and apparatus are provided for aligning one or more plies of material moving in a predetermined direction, and preferably through a desired path of travel, prior to stitching in a sewing machine. A friction wheel or other guide element is provided for applying a force to the ply having a component in a direction transverse to the direction of travel and sensors are provided for sensing the transverse position of the ply at the point where the sensor is located relative to the desired transverse position at that point. The sensor outputs are weighted, and where two or more sensors are provided, the sensor outputs are combined in a predetermined manner. The combined and weighted outputs are then utilized to control the transverse force applied by the guide element to the ply. The operating speed of the sewing machine may be utilized either as an additional input to control transverse force or to control the rate at which adjustments are made to the transverse force.