Fs340_02b_oi_e.docx / Nov-21
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Functional Description
Principle of Operation
The shear or saw blade is fixed on a carriage that can move in forward and reverse direction,
under control of a +/- 10 volts speed reference signal, with a 4-quadrant DC or Servo or Vector
drive.
Initially, the carriage keeps waiting in its rear home position, while the controller counts the
current length of the passing material by means of encoder signals from a line roll or a
measuring wheel.
As soon as the cutting point approaches an anticipated position, the carriage will accelerate
and reach the line speed exactly where the cutting position matches the tool position. A
“Ready
-to-
Cut” output will start the cutting procedure, while the carriage
will exactly follow
the material. When the cut is done, a remote “Cut completed” signal must tell the controller to
decelerate and then return the carriage back to the home position again.
All speed transitions use self-optimizing S-shape profiles for minimum wear and tear of all
mechanical parts, unless a linear ramp form has specifically been selected by corresponding
parameter setting.
t
v
Line Speed
Cut
The FS340 or FS641 controller continuously measures the line speed and calculates an
anticipation value to start the carriage before the cutting length is reached. Thus, the shear will
exactly match the cutting position of the material upon completion of the acceleration ramp and
no overshoot or oscillation will take place prior to the cut. This saves time and increases the
cutting efficiency of the shear system considerably.
