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:
Jan. 27, 1981
Filed:
Mar. 21, 1980
Tohru Gonnai, Nagoya, JP;
Brother Kogyo Kabushiki Kaisha, Aichi, JP;
Abstract
A thread tensioning device for a sewing machine, which is capable of automatically imparting, without any manual operation, a thread passing therethrough a suitable tension for the ordinary sewing, in accordance with the kind of thread as well as the thickness thereof. The device includes a pair of plate members closely confronted to each other for forming a narrow gap therebetween, being constantly urged by spring force acting at a concentrated point on one of the two members, and either one is provided with, on the inside surface thereof, a plurality of grooves formed perpendicularly to the direction of the thread running, each groove having a sharpened edge between the side surface of the groove facing the thread advancing direction and the thread engaging surface of the plate member for imparting a resistance independent of the spring force to the thread according to the surface condition thereof peculiar to each kind of threads.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile