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. 03, 1991
Filed:
Jun. 08, 1990
Takashi Nakamura, Hachioji, JP;
Haruhiko Tanaka, Hachioji, JP;
Akira Orii, Hachioji, JP;
Toru Hyodo, Sagamihara, JP;
Janome Sewing Machine Co., Ltd., Tokyo, JP;
Abstract
An amount of a lower thread to be supplied from a bobbin in each stitch forming operation is first determined on a theoretical basis in accordance with the stitch control data stored in a pattern memory. The sewing machine is provided with a bobbin rotation detector which detects every rotation of the bobbin to estimate a lower thread amount which has actually been supplied from the bobbin. A control unit compares the theoretical amount and the practical amount to lead out a correction coefficient which will be applied to the theoretical amount for the next stitch forming operation.