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Sequential Firing Method for Multi-in-line Row Matrix Printhead

IP.com Disclosure Number: IPCOM000121927D
Original Publication Date: 1991-Oct-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 5 page(s) / 139K

Publishing Venue

IBM

Related People

Katoh, H: AUTHOR [+2]

Abstract

Disclosed is a print element alignment and control method of a dot matrix printhead considering to fire the adjacent print elements sequentially.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Sequential Firing Method for Multi-in-line Row Matrix Printhead

      Disclosed is a print element alignment and control method
of a dot matrix printhead considering to fire the adjacent print
elements sequentially.

      The printhead of interest includes a dot matrix printhead of a
serial printer which has multiple print elements in a horizontal row
line to obtain many times faster print speed as single element
repeatability by alternative sharing of print data in a line.

      Aligning the horizontal spacing of vertical adjacent elements
by 1/n of print dot pitch, where n is a natural number 2,3,..., and
determining the print dot position sharing by the multiple elements
to alter by every n rows, each of the elements is fired as 1/n of
dot print time staggered to its vertical adjacent elements, and the
entire fire sequence is controlled to be sequential from top to
bottom.

      Figs. 1 and 2 show a typical application where n is 2, to two
in-line row matrix printhead of 18 elements.  The printhead can
generate a character of 9 vertical dots configuration.

      Fig. 1 is an alignment of print elements.  Those which aligned
in a line, such as 1A and 1B, share the same print line.  When the
printhead moves from left to right, the B elements lead and the A
elements trail.  Vertical adjacent elements, such as 1A and 2A, or 2A
and 3A are aligned with horizontal spacing of 1/2 dot.

      The circuit is controlled by the CPU 201 which generates print
image data into the buffer memory 202, and reads out the print data
slice from the memory, then writes them to the slice latch 203 at
every dot print time synchronizing the dot clock of the encoder 204.
The CPU also sets the timer values of the timing generator 205 which
outputs fire timing pulse with specified width.

      Each print dot data is distributed by the data distributor 206
alternately at the dot clock to the each data latch of leading
elements and trailing elements.  The data distributed to the leading
elements are directly stored to the data latch of leading column 208.
The data distributed to the trailing elements are delayed by the
shift register 207 as desired dot count matching to the displacement
of t...