The Untold 2D Inkjet Fax Printer and 3D Inkjet printer "Inkjets" Story

From: Jim McMahon <jim_at_layergrownmodel.com>
Date: Sun, 4 Dec 2016 05:10:43 -0500

"Music, Physics and Engineering" is a book about sound resonances and
instruments. This book captured my imagination in 1972 while I was student
teaching Physics. I couldn't keep a tune in my head and never appreciated
music but I had to have this book. I moved it around for 5 years from town
to town while I taught in a middle school and then quit teaching to go work
in industry. My first assignment was to mount a Zoltan style glass tubular
inkjet on a fax machine at Exxon Office Systems in 1978. Much to the
surprise of engineers, the 2D text printed on plain paper with this inkjet
randomly changed to BOLD text. IBM's Frank Talke had not published his
explanation for fluid resonant behavior in inkjets until 1984 but I
proposed fluid resonant behavior in these glass nozzles and identified the
cause of the light phase - dark phase printing that led to my patent on
"improved inkjet printing System" in 1979. This problem with 2D printing
resulted in new design of an inkjet with constant drop volume while firing
drops over 10,000 drops per second which was achieved at Howtek, Inc in
1984 using that same style Zoltan inkjet made of glass and a PZT ceramic
tubular 'squeeze' technology drop generator. In 1985, Mass production
failures of this hand made glass nozzle led to a machine molded version
made of Tefzel that naturally dampened out unwanted vibration frequencies
seen in previous glass nozzles and the ceramic tubular structures that were
now filled with a 125C Thermoplastic liquid. This new structure allowed for
even higher drive frequencies that were limited to the natural fluid
response of this structure or the fluid structural resonance as seen in
musical instruments that have air as the medium. This negative
characteristic of the Zoltan inkjet design became a bonus when a need for
high output fluid volumes were called for when printing 3D models. Today
the fluid resonant mode of operation is standard on 3D Inkjet printers
using the squeeze mode of operation. Squeeze mode is little known in the
world of 3D printing because it used in only one popular 3D printer. The
1979 patent referred to earlier used the fluid resonance characteristic to
clear fluid from a nozzle orifice by sucking the fluid back into the
nozzle. That invention was intended to show fluid resonance is very strong
and is capable of delivering extremely high volumes of fluid both in and
out of the nozzle. In reverse resonant mode a tiny glass nozzle inkjet can
pull 48 inches of fluid head in a column. Zoltan style Drop on Demand
Inkjets (Patented in 1972) can be drop generators or fluid pumps and are
fundamental to the existence of the first 3D Inkjet printer manufactured in
USA in 1994 by Sanders Prototype, Inc. These items can be seen in the
"collection" that may someday be shown in a 3D Ink Jet Museum in New
Hampshire.
Received on Sun Dec 04 2016 - 12:11:10 EET