It's hats off to Youngs' in-house engineering team for designing and
building its own fully automated fish finger packing line - a DIY project
made possible thanks to the team's enterprise and, in no small part, to
some user-friendly motion control technology from Control Techniques
When Youngs Bluecrest Seafood decided to upgrade a packing line for fish
fingers, it went for the DIY option, using a M'Ax servo system with SLM
technology from Control Techniques (CT). And the result? The removal of a
production bottleneck, a saving of some £180,000 per year and an increase
in production. The new, fully automated line packs 50 fish fingers at a
time into cardboard boxes - previously a manual operation involving 27
people. Factory engineer, Stuart Baker takes up the story.
We looked at the options available to us and realised that we could
build a fully automatic machine ourselves for the same cost as buying in
a semi-automatic one. But it all hinged on the servo system. After we
undertook a technical appraisal, we chose Control Techniques' M'Ax with
four-wire SLM for its flexibility, ease of programming and greatly reduce
wiring requirement.
The system comprises a CT MC216 motion controller providing up to 16
axes, eight M'Ax single-axis servo drives and eight SL Unimotors
incorporating SLM technology. As the product moves across a vibrating
deck it is collated into 50 lines. Five packs at a time are indexed into
the packing machine, using a registration input to measure the carton
distance to the pneumatic stop. A servomotor provides a finger lifting
and separating action from beneath the deck to prevent any sticking.
Servos then provide indexing into a collating plate, which pushes the
blocks of product into the correct width for the box. A vacuum
pick-and-place unit lifts five carton-loads at a time and places them in
their boxes. An acceleration conveyor rapidly clears the boxes ready for
the next batch. Mechanical design was simplified by pairing three of the
six axes - ie two servomotors on each shaft.
SLM technology uses the motor-mounted SinCos encoder and DSP techniques
to provide very high resolution control. Cabling costs are cut by up to
two thirds, and an error-free signal is assured, thanks to a high-speed
dedicated bus system. The SL motor features a module with built-in speed
loop electronics and a special encoder interface. this speed/position
transducer provides a resolution greater than eight million points per
revolution. Moreover, with a lot of the system intelligence centred on
the motor, the update loop response is cut to just 125ns, and a truly
impressive axis-to-axis synchronisation of 50ns.
SLM was a key factor in our choice of the CT system, Mr Baker recalls.
It greatly simplified not only the build and installation, but also -
thanks to its extensive diagnostics - reduced maintenance time too. The
system really is easy to use. We can even adjust gains while the machine
is operating, and we're all very impressed.