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:
Jan. 24, 1995
Filed:
Sep. 27, 1993
Trevor J German, Waterloo, CA;
NCR Corporation, Dayton, OH (US);
Abstract
A method and apparatus for controlling the adjustment of printer hammers which impact against an associated moveable member on which characters are present. Each hammer includes a coil which is energized at the appropriate time, taking into consideration the 'flight time' of the associated hammer. These flight times are determined by detecting a change in the back EMF in the energizing current to the coil. These flight times are averaged to obtain a running average of the last several successive flight times (for each hammer in the printer), and successive timing pulses from a timing disc are used to obtain an almost instantaneous velocity of the moveable member (like a printer drum) just prior to a character to be printed. The last several successive flight times are stored in a non-volatile RAM of a controller to enable the printer to be ready at a next start up.