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:
Aug. 28, 1984
Filed:
Sep. 28, 1981
John Willigman, Elk Grove Village, IL (US);
Guy A Wojtanek, Schiller Park, IL (US);
The Singer Company, Stamford, CT (US);
Abstract
The timing cam is advanced for switching purposes by the large reciprocating pawl acting on the ratchet teeth molded on the timing cam. When the program requires a timed period during which conditions remain the same the ratchet teeth are spaced so the pawl cannot pick up the next tooth until the cam is advanced by the small pawl acting on the separate ratchet provided with small, closely spaced teeth. This ratchet has a pinion gear driving the ring gear molded inside the timing cam. The steps imparted to the timing cam by the small pawl and ratchet are very small and consume appreciable time--the length of time taken to position the next tooth for engagement by the large pawl being determined by the space between the large teeth.