EDITOR’S CHOICE
DESIGNED FOR THE XTREME
KOYO
FROM PRINT MISALIGNMENT TO ELECTRIC CARS, HOW
KOYO HIGH PERFORMANCE TRACTION DRIVES WENT
FROM INNOVATION TO INDUSTRY STANDARD
the unevenness was always outside
acceptable levels.
In the field of graphic visual printing
aesthetics is everything and printing
misalignment due to uneven rotation can be
described as a problem directly impacting
creditability, reliability and MRO costs.
To help solve the issue Koyo developed a
traction drive to replace the planetary gear
systems that were available at that time.
Planetary gear systems have large speed
variations which make them unsuitable for
this application, but the traction drive solved
the problems caused by the gear systems
and reduced uneven rotation by up to 80%
(Rotational speed variation (%) = (Speed
variation amount / output axis average
rotation speed) x 100).
Koyo are well known for producing
high precision components for extreme
applications but in 1987 they were
challenged to reduce uneven rotation by
80%.
By today’s standards the 80s were filled with
uneven rotation, vibration and excessive
noise which were accepted parts of the
traditional planetary gear systems so when
Koyo were challenged to increase precision
they were happy to help.
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PECM Issue 34
Just 12 months later they delivered Koyo’s
first traction drive. The client was a high-
performance commercial printing press
manufacturer and their challenge was
to eradicate tiny movements within the
existing planetary gear system which caused
unevenness in the feed drum rotation and
unacceptable variations in the print.
There were, at the time, several solutions
that will allow you to reduce the relative
unevenness however no matter how
carefully the existing unit was manufactured
Minute uneven rotation now facilitates the
production of high performance printing
machines.
The traction drive itself features bearing
technology accumulated by the Koyo
brand combining high accuracy machining
with a deep knowledge of tribology, heat
treatment and analysis.
By leveraging proven machining capabilities
at a micron level and optimizing traction
grease (lubricant) that sways friction
between rollers it was possible to
achieve highly accurate feed with a high