Even Arthur Bräuer was immediately enthusiastic. Since there
are angle-arm robots, cable carriers again and again cause
problems. Even the common corrugated tubes are not the
cleverest solution. So far Bräuer made good experience with
the products of Kabelschlepp. Therefore he wanted to test
Robotrax.
In a cell a robot has to combine three working steps:
Pre-assembly, welding and calibration of parts for the front
axle of the Ford Focus. The robot was manufactured by the
company Reis in Obernburg, The system company Bräuer in
Kirchhundem built the cell, which is working at the company
Fischer and Kaufmann. The cell will produce about 350 pieces
per hour in a three-shift operation. This results in more
than 100.000 movements for the cable carrier and the
cables/hoses per day.
The head of the robot must be supplied with media, energy
and control impulses: a multi-core electric cable and two
water hoses for cooling. The so far common corrugated tubes
show several disadvantages: The minimum bend radius cannot
be defined, the cables must be lubricated and single cables
cannot be exchanged. The Robotrax-cable carrier, however,
does not fall under the minimum defined bend radius, thus
saving the cables. As the cables are guided separately in
chambers the friction is reduced. Due to the slots in the
links cables/hoses can easily be added or exchanged –
especially during the test phases of the cell an inestimable
advantage.
Model: spinal column
The new type of cable carrier consists of round plastic
parts being clipped together along their turning angle. The
spherical snap joint is designed in a way that a radial turn
of the links is possible. On one meter length this results
in a turning angle of +/- 215 degrees. A steel rope is
pulled through the chain which transfers the high forces
caused by the movements of the robot. The connecting element
between chain and robot arm is designed in a way that it can
be fixed to every link. This is important as the connecting
points can only be found out by trying. The half bowl of the
connection can easily be removed for exchanging a cable.
Even complete systems can quickly be assembled or exchanged.
The movement of the axis 1 by 360 degrees on the floor
causes special difficulties for the cable carrier. But there
are two constructive solutions. The chain is either laid
around the robot foot through a truncated cone or caught in
a magazine box.
But the turning movement can also be realized without
guiding system.
Even with this project no guiding channel was required. The
robot turns by nearly 180 degrees but even bigger turning
angles are possible without channel system.
Kabelschlepp also offers complete systems consisting of
cables, plugs and hoses.
A Question of price
Even compared to the common corrugated tubes the Robotrax
is more reasonably priced. Further to the price advantage
there are the technical advantages. „The price must always
be related to the properties of the chain“, said Bräuer
after having been asked for the costs. If lifetime, assembly
friendliness, flexibility etc. are right the price is not
very important for the basic equipment.
The cable carrier Robotrax has been fitted to many
installations since its introduction to the market at the
latest Hanover Fair. The manufacturer took up many
suggestions of robot manufacturers. This year four
additional sizes and accessories such as integrated strain
relief will be offered. Bräuer will then also fit a small
chain to his robot for guiding cables at the robot head. |
