3 Fundamentals of press design

Sheet metal forming lines
In modern press lines, workpiece transport between the individual
presses as well as blank feed are automatically executed. Automatic
stacking of finished parts is used wherever approximately identical
stacking conditions, part shapes and sizes exist (Fig.4.4.41). A number
of different automation systems are used: swing arm feeders, CNC feeders
or robots. The type of automation most suitable for any particular
line depends on the range of parts being processed, the stroking rate
and the available space.
Swing arm feeders are driven by electric motors via cams and links
(Fig. 4.4.21). The feeder at the rear of the press removes the drawn part,
which has been raised in the die by ejectors, by means of suction cups
and a suction cup carrier and places it on an intermediate station. From
here, the workpiece is turned over if required and loaded into the next
die by the feeder of the downstream press. Swing arm feeders have fixed
motion curves, making them suitable for small press distances, medium-sized
parts and similar part types. They can transport between 10
and 12 medium-sized components a minute.
CNC feeders are electrically controlled and as such can be freely programmed
on two axes and used for a wide variety of part types. Drive is
performed by means of two spindle mechanisms or timing belt-driven
carriages (Fig.4.4.22). They are able to remove the part from the die
blankfeeder
CNC feeder
washingmachine turno er station intermediate station
Fig. 4.4.22 Interlinkage of presses with CNC feeders and timing belt-driven carriages
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
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CNC feeder