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:
Nov. 09, 1976
Filed:
Oct. 20, 1975
Donald P Martin, Chicago, IL (US);
Richard G Ryan, Elmhurst, IL (US);
Extel Corporation, Northbrook, IL (US);
Abstract
A method and apparatus for controlling the print rate of a column-sequential dot matrix printer actuated by an input signal comprising a sequence of code words occurring at a given maximum input rate, a print head and a print head drive operating at a speed determined by the frequency of a print rate timing signal, and a multi-stage FIFO input storage register. A multiplicity of constant-frequency print rate timing signals are generated, ranging in frequency from substantially below to substantially above a normal print rate frequency Fn approximately matched to the input rate, and a variable print rate timing signal progressively increasing in frequency from well below Fn to well above Fn is also generated; these signals are applied to the printer in accordance with a predetermined schedule, determined by the number of code words in storage at the beginning of each spacing character cycle, and in accordance with a program affording relatively smooth acceleration and deceleration of the print head. In continuing operation, the number of code words in storage is accumulated to a given level and maintained approximately at that level until the input is interrupted.