Patent · US Expired

Method and apparatus for coordinated control of dot matrix printer head and carriage

US4468140A · kind A · utility

9Cited by
6References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 16, 1982
Grant dateAug 28, 1984
Priority date
Expiry dateJul 16, 2002

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06K15/10
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A dot matrix printer has a programmable interval counter which produces motion control pulses for stepping the stepper motor of a print head carriage and/or of a paper advance system. The same motion control pulse which is used to control the carriage step motor is also input to a microprocessor, in an open loop fashion, to request further print head data for driving the wire array(s) of the dot matrix print head. A programmed time delay may be introduced between the programmable interval counter and the carriage step motor to compensate for wire flight time of the print head wires in a manner which is substantially independent of carriage velocity. A variable delay may also be introduced between the programmable interval counter and the microprocessor to compensate for carriage motor shaft lag/lead. The number of print operations per control pulse and the number of control pulses per print operation may be independently controlled to increase the print density and quality by inserting programmable divider/counters between the programmable interval counter and the microprocessor and/or the carriage stepper motor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.