Getting involved - KBA-Metronic

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Technology | Identification Technology
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Getting involved
MARKING There's no getting away from precise marking in industrial production.
The two-dimensional data matrix code allows a huge amount of data to be stored.
All you need is the right printer.
Hofmann Mess- und Auswuchttechnik,
based in
Pfungstadt, Germany,
has been building automatic,
semiautomatic and manually
operated balancing machines
for 70 years. With a workforce
of 120, the medium-sized business
likes to offer its customers
full and professional support
through the use of cuttingedge
technology, engineering
and services. In one of its latest
applications a Hofmann balancing
machine enables starter
ring gears in cars to run uniformly.
The machine does so
by welding metal strips fully
automatically to the ring gears,
thereby balancing them.
An integrated geometry measuring
station also records all
the necessary data in the
operation. Once the imbalance
of the starter ring gears has
been compensated and the
geometric values have been
verified, the test result on every
single component must be
documented.
Hofmann has integrated an
inkjet printer into its balancing
machine delivery line for just
that purpose. It applies a data
matrix code in 2D including
AUTOMATION 4|2006
clear text marking as a unique
identifier.
This special code significantly
increases the density of information
per unit of surface
area compared with onedimensional
barcodes. For
marking the starter ring gears,
the code consists of 36 characters
with an edge length of
»We can mark easily
and with high precision
with the alphaJET C.«
Georg Fischer
6.8 mm. The printer has to
meet certain basic criteria. For
one thing, it is absolutely
essential that the code is
printed with particular accuracy
and precision if legibility is to
be guaranteed. Secondly, the
marking process should be fast,
cost-saving and reliable so that
the production schedule is not
impaired. The 30 millimeterhigh
bead around presents a
particular challenge in this case
because it means that the print
head must be 33 millimeters
away from the print surface.
To reduce costs and time,
managers were looking for a
method that performed
marking without using a
positioning unit.
Contact-free
In the course of its search,
Hofmann discovered the solution
offered by KBA-Metronic
AG. The mid-sized enterprise
with 300 employees is based in
Veitshöchheim, Germany, and
is a full-service provider specializing
in the development,
design, production and marketing
of print and marking
technology. KBA-Metronic
developed contact-free printing
for just such applications.
"We were delighted", says
Georg Fischer, Technical Director
at Hofmann, "to have
come across the alphaJET C
inkjet printer from KBA-
Metronic. This machine enables
us to mark easily and with high
precision from a print head
distance of 33 mm."
This feature, says the manufacturer,
is unique among the
inkjet systems currently available
on the market. Printing is
enabled by the contact-free
continuous inkjet process.
Thanks to the 48-dot matrix,
the print head of the alphaJET
C can print up to six lines and,
what is more, the individual
lines can also be shifted pixel
by pixel. This means that the
printer can reliably meet the
high requirements on resolution
and type quality typical
for data matrix codes. It is ideal
for the printing on almost any
product and material, is freely
programmable and can be
easily integrated into all
product lines.
Cross-checking
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To ensure legibility, the data
matrix reader HawkEye
1525HD reads the code again
after marking. Communication
with the system control is by
Profibus-DP, while the Ethernet
interface enables remote
operation and monitoring of
the system. An aluminum
protective housing with IP 67
rating is fitted on the reader
to enable use in tough industrial
environments.
As Georg Fischer sums up: "Our
customers need professional
and usually immediate advice

for their special requirements.
That means that individual and
financially viable solutions have
to be found more or less
straight away."
That's why Hofmann values
KBA-Metronic AG as a reliable
and professional partner when
it comes to hard-to-handle jobs.
www.kba-metronic.com
FACTS & FIGURES
The alphaJET C
‡ Dimensions:
295 x 320 x 655 mm,
stainless steel housing
‡ Print system:
0.5 l ink storage tank,
easy to replenish,
no compressed air
connection required
‡ Speed:
2500 characters per second
‡ Print head distance:
2 - 25 mm,
for applications such as
the above up to 33 mm
‡ Type height:
0.8 - 15 mm, max. 6 lines
‡ Print resolution:
48 dots vertical,
dot matrix freely selectable
‡ Interfaces:
2 x RS 232
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1 In the alphaJET C Hofmann
found the right printer for marking
its gear wheels with maximum
precision.
2 The print head of the alphaJET C
prints accurately on every gear
wheel despite the large side bead.
3 Every balanced gear wheel
carries a 2D data matrix code.
4 The reader HawkEye 1525HD
continually cross-checks the code
applied in the operation.
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