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. 01, 1987
Filed:
Nov. 12, 1985
Janome Sewing Machine Co. Ltd., Tokyo, JP;
Abstract
An automatic thread tension adjusting device for a sewing machine designed to automatically adjust the tension of upper thread to produce desired stitches each formed with the upper and lower threads interlocked with each other within the thickness of a fabric to be sewn, the interlocking position of the threads depending upon the types of stitches such as the straight stitches and zigzag stitches. The thread is held and drawn-out at predetermined angular positions of an upper drive shaft, which are detected by sensors to thereby draw out a required amount of upper thread depending upon the thickness of the fabric and the type of stitches. The required amount of the upper thread is supplied to a thread take-up lever to determine the upper thread tension during the formation process of each stitch.