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:
Feb. 19, 1980
Filed:
May. 18, 1979
William Kahan, New York, NY (US);
The Singer Company, New York, NY (US);
Abstract
A bobbin thread run-out detector having a light source and means for directing a beam of light toward a set of retro-reflecting reflectors on the bobbin and toward a reference reflecting spot on the loop taker. Bobbin thread wound around the bobbin is interposed between the light source and the retro-reflecting reflectors. When a sufficient quantity of thread has been consumed to expose the indentations to the source of light, the light is reflected to a photodetector. Light from the source is also intermittently reflected onto the photodetector by the reflecting spot on the loop taker during each revolution of the loop taker. An electronic circuit compares the light received by the photodetector from the bobbin with the light received from the reflecting spot on the loop taker. When the quantity of light reflected from the bobbin changes relative to the quantity of light reflected from the loop taker a low bobbin thread alarm is activated to warn the operator of the impending exhaustion of bobbin thread.