Omron TJ2-MC64 - PROGRAMMING Programming Manual page 345

Examples and tips
GOTO loop
The speed-time graph shows the steps of the above example. The steps
are:
1. The initial cycle: the slave waits for the right length in the product to cut
(cut_length – distance_to_accelerate / 2). It is necessary to divide
distance_to_accelerate when we use the MOVELINK command,
because when we synchronize, the master moves twice the distance of
the slave.
2. The slave accelerates to synchronize with the master. When the
acceleration finishes, the relative distance between the edge of the
product and the shear is cut_length.
3. This is the synchronization part: the relative distance between the edge
of the product and the shear remains the same. The cut in the material is
made. This gives a new material edge.
4. The deceleration part: the material continues, and the shear stops.
5. Move back at high speed: the distances are calculated such that when
the slave reaches it original position, the edge of the product is in the
correct position to start a new cut.A
A new movement starts (step 2).
5.2.9 Correction program
This application is for a rotary labeller. The constants are:
• The product arrives on a conveyor (master axis) that runs at a constant
speed.
• A rotary labeller that is synchronized 1:1 to the conveyor, attaches the
labels.
• The distance between products is fixed and mechanically guaranteed.
The distance between labels is never exactly constant so, a correction is
needed. This is done by superimposing a virtual axis onto the movement of
the labeller.
PROGRAMMING MANUAL
SPEED
1 2 3
fig. 58
4 5 2
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