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Elastomeric Dampener Used in Shear for LINAC Hammer

IP.com Disclosure Number: IPCOM000108649D
Original Publication Date: 1992-Jun-01
Included in the Prior Art Database: 2005-Mar-22
Document File: 3 page(s) / 121K

Publishing Venue

IBM

Related People

Groves, LK: AUTHOR [+5]

Abstract

Dampeners are used in impact printers to increase printing speed. In an impact printer a hammer of print actuator strikes a character forming element to create a mark on a document. The rate at which hammers are fired is called the repetition rate, or more commonly, the rep rate. As print speed is directly related to the hammer rep rate it is important that the rep rate be as high as possible. One important factor that determines hammer rep rate is settle-out time. Settle-out time is the time period when the hammer has returned to the original start position but still has some of the unused energy from the previous actuation stored within the hammer mechanism.

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Elastomeric Dampener Used in Shear for LINAC Hammer

       Dampeners are used in impact printers to increase
printing speed.  In an impact printer a hammer of print actuator
strikes a character forming element to create a mark on a document.
The rate at which hammers are fired is called the repetition rate, or
more commonly, the rep rate.  As print speed is directly related to
the hammer rep rate it is important that the rep rate be as high as
possible.  One important factor that determines hammer rep rate is
settle-out time. Settle-out time is the time period when the hammer
has returned to the original start position but still has some of the
unused energy from the previous actuation stored within the hammer
mechanism.  Should the hammer be fired before the energy is
dissipated, irregular flight times would result with a concomitant
degradation in print registration; prudence requires that settle-out
be complete before firing the hammer again.  Shortening the
settle-out time increases the rep rate and ultimately the printing
speed.

      A dampener found useful with the Linear Actuator (LINAC) is an
elastomeric rubber dampener comprised of two or more rubber pieces in
a shear relationship.  In particular, this shear type rubber dampener
provides superior settle-out characteristics and improved
performance.

      Referring to Fig. 1, an outer shell of supportive material,
such as plastic, is formed into a channel shaped structure 1.  To the
two opposite internal walls 2 of the channel structure 1 are bonded,
by adhesives (or other suitable means), thin layers of
energy-absorbing rubber 3 such as polyacrylic rubber or butyl rubber.
Between these two opposing pieces of rubber 3 is bonded by adhesives
(or by other suitable means) a backstop 4 constructed of plastic (or
metal such as aluminum).  When the actuator 5 rebounds from the paper
after having been fired to produce a dot, it returns to its start
position and strikes the backstop 4 that is sandwiched in between the
two pieces of rubber 3.  The energy of the actuator 5 being
transferred to the backs...