Cut-to-Length or Cut-to-Mark
The rotary cutoff control cuts a continuously moving strip of material into specified lengths. A measuring wheel is used to track the movement of the material. Two different modes offer the choice of cutting prescribed lengths or cutting relative to printed registration marks or holes using a mark detector to scan the material. Windowing features minimize spurious mark errors during registration cutting.
Pattern Recognition
The drive can search for a user-defined pattern of marks or holes in the material. When a pattern or hole is recognized, the shear makes a cut at a specific location relative to the last mark in the pattern. A pattern tolerance setup establishes the degree to which the distance between consecutive marks can vary from the set distance and still be considered a valid part of the pattern.
Simulators
Two simulation tools facilitate setting up, testing, and troubleshooting a rotary cutoff system. A line simulator makes it possible to run the cutoff without material by simulating the feedback that the measuring wheel or pull roll would provide as the line ramps up, ramps down, or runs at speed. A mark detector simulator provides marks at a specified separation to allow testing in cut-to-mark mode.
Cut Torque Boost and Limit
A torque boost option applies torque during the cut to prevent speed droop during the cut.
Batch Control
Two different part lengths and batch sizes can be specified at once, allowing the operator to set up the next order while the current one is running. In cut-to-mark mode, batches also specify the mark offset and up to eight pattern edges. Orders change automatically at the end of a batch or when requested by the operator. A customizable early warning feature indicates when a batch is nearly complete. A single length may also be produced indefinitely.
Cut Angle Calculation
The ideal cut angle is automatically calculated from shear and material data. The program accommodates four different blade types: driven bow-tie, driven straight, undriven bow-tie, and undriven straight.
Smooth Cut
The drive latches the line speed at the beginning of a cut and follows this speed while the shear is engaged in the material. This feature is necessary with heavy gauge material to prevent the shear from stalling during the cut.
Back-Up
When producing long lengths, the shear is stopped at a point beyond top and backed up to a point an equal distance ahead of top. This allows longer acceleration and deceleration distances required for higher line speeds.
Dual-Motor Operation
The control supports both single- and dual-motor operation. If two motors are coupled to the knife, the user must arbitrarily choose one as the master and the other as the slave.
Maximum Line Velocity Calculation
The program calculates the maximum velocity at which the line can operate based upon part length. The velocity is computed using a number of parameters that describe the shear, the shear motor, the shear drive, and the material.
Early Warning
An early warning output is set when the batch is nearly completed. The output can be used to alert the operator or to slow the line down.
Cam Outputs
Programmable limit switch (PLS) outputs replace mechanical cams by electronically following the position of the rotary cutoff.
