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. 19, 1980
Filed:
Nov. 20, 1978
Ronald L Swaim, Sunnyvale, CA (US);
Vydec, Inc., Florham Park, NJ (US);
Abstract
A moving coil mechanism is utilized to operate each individual print wire of a matrix printing head. Static magnetic fields for the moving coil mechanism may be provided by permanent magnets. Also disclosed is a method for compensating varying frictional forces by sensing the voltage induced in the moving coil and utilizing the information so obtained as an indication of print wire velocity. Current drive to the moving coil can then be modified to maintain print wire velocity substantially independent of varying frictional forces. Also disclosed is an interspersed, or 'nested,' arrangement of moving coil mechanisms which contributes to the compactness of the improved matrix printer.