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. 04, 1979
Filed:
Sep. 06, 1978
Robert E Porter, Hamilton, MA (US);
Other;
Abstract
A top feeding device for advancing the upper layer of material in synchronism with the lower layer of material being sewn. The top feeding device includes an upper feed dog moving periodically in conjunction with a lower feed dog to grip and advance the materials being sewn along a path related to the stroke of the stitching needle or needles of the sewing machine. Drive for the top feeder is derived from an eccentric cam mounted on the sewing machine main drive shaft, motion being positively transferred to a pivotal upper feed dog arm by means of a lever arm depending from that arm and being a cam-following surface held under adjustable pressure in contact with the eccentric cam. The pivot for the upper feed dog arm is disposed upon an extension of the main lower feed bar which thereby provides horizontal motion to both the upper and lower feed dog arms.