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. 20, 1988
Filed:
Feb. 19, 1987
Toshio Sasaki, Nagoya, JP;
Masao Ogawa, Nagoya, JP;
Brother Kogyo Kabushiki Kaisha, Aichi, JP;
Abstract
In a conventional sewing machine, as the take-up lever is driven by the take-up lever crank, the take-up lever does not keep its uppermost position during the feed motion of a work fabric. Accordingly, the length of the thread path extending from the thread supply source to the eye of the needle varies remarkably during feed motion, and thus the needle thread equivalent to the amount consumed by stitch feed motion cannot be extracted from the supply source. In the present automatic needle thread supply control system, during a specific period from a time before finishing of each feed motion to a time when the needle reaches the throat plate, the take-up lever is held at its uppermost position. During a given period corresponding to the comparatively latter half of the specified period, thread supply stopping is released, whereby the needle thread equivalent to the amount consumed by each stitch feed motion can be extracted certainly from the supply source toward the take-up lever. The present thread supply control system comprises, at least, thread securing means or driving means, thread supply stopping means and mechanical control means.