Wire Cutting Servo Application

This machine cuts pins from a reel of wire very at high speed, most probably the fastest machine built at 20+ pins per second. Each move or cut must be accurate within a few microns for the wire to pass exactly through the cutter.  The Parker 637F servo drive uses a trigger sensor to detect the wire has reached the exact length before making the cut move. During the design stage the reflected load inertia was calculated and matched with the Parker NX620EAV servo motor for a fast cut time. During tuning the Speed and current, and position loop gains have been tuned for optimum move speed without the servo becoming unstable.

The incremental move position is taken from the servo resolver, each move is an irrational number and integral number within the Visual Basic servo program, because of this the accumulated error is offset every 64 move commands.

The servo drive, motor and Wittenstein gear box has completed 1.35 Billion cuts without failure over 9.5 years.

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