Browse Prior Art Database

Continuous Forms Output Buffer

IP.com Disclosure Number: IPCOM000109887D
Original Publication Date: 1992-Sep-01
Included in the Prior Art Database: 2005-Mar-24
Document File: 4 page(s) / 142K

Publishing Venue

IBM

Related People

Bellamy, L: AUTHOR [+15]

Abstract

Disclosed is a means to vary the paperline tension through the transfer station and fuser so as to solve the problems associated with printing to the perforations on a wide variety of continuous forms.

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

Continuous Forms Output Buffer

       Disclosed is a means to vary the paperline tension
through the transfer station and fuser so as to solve the problems
associated with printing to the perforations on a wide variety of
continuous forms.

      The output buffer is the device that provides tension in the
paperline through the transfer station and fuser.  A side view of the
buffer is shown in Fig. 1.  The tension is provided by reducing air
pressure on the backside of a loop of paper that is formed between
top and bottom plates.  Two sides of the loop are sealed by a fixed
wall and a movable wall.  The movable wall is operator adjustable to
accommodate varying paper widths.

      Paper is fed into the buffer by tractors located at the input
to the transfer station.  Paper motion out of the buffer is
controlled by a roll driven by a DC servo motor.  Whenever the
tractors are feeding paper forward, the buffer exit roll feeds paper
out of the buffer.  If the loop of paper in the buffer covers the
servo sensor, then the roll feeds paper out of the buffer at
120-percent of process speed.  If the loop of paper does not cover
the servo sensor, then the roll runs at 80-percent of process speed.
The result of this control is that the loop of paper is caused to
stay at, or near, the servo sensor.

      The paperline is lifted away from the photoconductor once per
belt revolution to clear the belt seam.  When this is done, the
paperline is lifted away and then brought to a stop.  It is then
backed up (at process speed) approximately 2.5 inches.  When the next
image comes on the photoconductor, the paperline is accelerated to a
velocity to match the photoconductor and then is lowered to the
photoconductor so that the beginning of the new image is adjacent to
the end of the previous image.  Acceleration and deceleration of the
paperline occurs in 16 msec.  The buffer exit roll acceleration and
deceleration occurs in 32 msec.  The roll control is such that the
roll begins accelerating and decelerating 8 msec before the tractors.
This reduces the amount of vacuum perturbations caused by loop motion
in the column.  Fig. 2 shows the timings for the roll control.  The
buffer loses approximately 60 mm of paper every time the paperline is
stopped and backhitched.  In applications where complex jobs are run,
it is possible that backhitches can occur at image boundaries.  In
this case, the paper would eventually be backed out of the buffer and
an error would occur.  To prevent this from...