Omron TJ1-MC04 - PROGRAMMING 1 Programming Manual page 267

Examples and tips
The feeder can work in two modes: without registration mark; and
with registration mark. Working without the registration mark is a
simple point-to-point incremental movement. In this case, there is
no guarantee that the feeder moves exactly the same distance as
the design pattern. For example, suppose the bag length that
needs to be fed is 200 mm, but the real pattern is 200.1 mm. With
simple point-to-point incremental movement without correction, an
error of 0.1 mm per bag is accumulated. With a small number of
bags the difference is not visible, but after 500 bags the error is 50
mm, which is a 25% of the bag length.
When working with registration marks, the motion controller
executes an incremental movement to a certain position. If during
the positioning the registration mark is detected, the target position
is changed on the fly in order to finish the movement at a defined
position after the registration mark. Therefore, the same distance in
respect to the registration mark is always guaranteed.
PROGRAMMING MANUAL
fig. 38
Δd
20Δd
100Δd
After 1 bag After 20 bag
fig. 39
D
After 100 bag
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