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:
Dec. 07, 1976
Filed:
Jan. 07, 1976
Robert E Porter, Hamilton, MA (US);
Other;
Abstract
Disclosed is an improved top feed arrangement for cooperation with a conventional lower feed dog of a sewing machine, the lower feed dog cyclically engaging and disengaging the lower surface of material to be sewn in order to move that lower surface along a predetermined path through and past the sewing machine. The top feed arrangement comprises an upper feed dog carried by an arm that is pivotally linked to the drive means causing the cyclical movement of the lower feed dog. The arm is connected to those drive means at one end in a pivotal connection and the upper feed dog is carried at the other end of the arm. Biasing means bear against the arm at a location intermediate the upper feed dog and the pivotal connection to the drive means. A lifter means, responsive to the drive system that actuates the sewing machine needle, periodically moves the upper feed dog in a direction away from the lower feed dog against the force of the biasing means. Preferably, the arm which carries the upper feed dog is guided for movement in a vertical plane by a first bearing surface of the arm engaging a vertical confining surface of the sewing machine frame and a second bearing surface engaging a confining surface of the biasing means.