Control of gap between plasma burner and workpiece

摘要

The plasma cutting head is built into a CNC machine and the path is controlled to reproduce programmed shapes. The distance of the cutter 12 from the surface of the workpiece 13 is controlled by using a capacitor arrangement 37 to generate a displacement signal that is used in a capacitive bridge circuit 30 together with a reference capacitor 38. The output controls the cutter head drive 28.