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Browse Prior Art Database

Duplex Printing

IP.com Disclosure Number: IPCOM000120240D
Original Publication Date: 1991-Apr-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 3 page(s) / 95K

Publishing Venue

IBM

Related People

Decker, JW: AUTHOR [+4]

Abstract

An all-points-addressable (APA) printer is disclosed wherein paper handling is simplified by the expedient of "flipping" the electronic memory image which is to be printed on one side of the paper, rather than rotating the sheet itself.

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

Duplex Printing

      An all-points-addressable (APA) printer is disclosed
wherein paper handling is simplified by the expedient of "flipping"
the electronic memory image which is to be printed on one side of the
paper, rather than rotating the sheet itself.

      Fig. 1 discloses an electrophotographic APA printer having a
photoconductor drum 10 and a printhead 11.  A paper supply tray 12
holds a stack of cut plain paper to be used to selectively produce
simplex or duplex prints.  Printed sheets exit the printer by way of
exit tray 13, and reside facing down.  In order to insure proper
duplex pagination in exit tray 13, the sheets are printed even page
number side first.

      Sheets move through the printer with their short edge (for
example, the 8}-inch edge) as the sheet's leading edge.

      The printer of Fig. 1 can be configured for simplex printing
only by removal of module 14, or the printer can be upgraded to a
simplex/ duplex printer merely by the installation of module 14 which
includes two-position sheet pick/feeder mechanism 24.

      The images to be printed on a sheet are stored as binary images
in memory 21.  Memory 21 includes a portion 22 which contains the
binary image of page 1 (i.e., any odd-numbered page), and a portion
23 which contains the binary image of page 2 (i.e., the next numbered
page after the odd-numbered page in portion 22).

      In the printing of a duplex sheet, a blank sheet is first
picked from tray 12 and is sent through print station 15.  Fig. 2
depicts this operation.  In this figure, arrow 16 represents...