Method and apparatus for tracing patterns to develop multiaxes numerical programs for servo controlled machine tools

Abstract

Abstract THE MOTIONS OF A MOVABLE ELEMENT, SUCH AS THE CUTTER OF A MACHINE TOOL, ALONG A DESIRED ARBITRARY AND CONTOURED PATH ARE PRODUCED BY TRACING A FACSIMILE OR LINE DRAWING OF THE PATH WITH AN INSTRUMENT AND MEANSURING THE LATTER''S DISPLACEMENTS ALONG ORTHOGONAL AXES TO CREATE SUCCESSIVE BLOCKS OF NUMERICAL INFORMATION EACH DESIGNATING COMMANDED DISPLACEMENTS OF THE ELEMENT ALONG X AND Y AXES. THE SUCCESSIVE BLOCKS OF NUMBERICAL DATA ARE THEN USED IN A PROCESS OF SIMULTANEOUS LINEAR INTERPOLATION ALONG X AND Y AXES TO CAUSE THE MOVABLE ELEMENT TO EXECUTE THE DESIRED PATH. THE BLOCKS OF DATA CONTAIN NO FEED RATE OR VELOCITY-DESIGNATING INFORMATION. BUT THE FEED RATE OF THE ELEMENT ALONG THE PATH IS CONTROLLED BY (A) CAUSING THE X AND Y DISPLACEMENTS FOR SUCCESSIVE BLOCKS OF INFORMATION DURING THE TRACING STEP TO CORRESPOND TO SELECTED BUT EQUAL COMPOSITE DISTANCE INCREMENTS $D ALONG THE FACSIMILE LINE, AND (B) CAUSING THE X AND Y COMMANDS IN A BLOCK OF DATA TO BE EXECUTED DURING EQUAL SUCCESSIVE TIME INTERVALS. THE VELOCITY OF THE ELEMENT ALONG THE PATH IS THUS ALWAYS PROPORTIONAL TO THE COMPOSITE TRACING INCREMENT $D AND IS CONTROLLED BY SELECTING DIFFERENT VALUES FOR THAT INCRMENT. IN THOSE SITUATIONS WHEN THE CHOSEN INCREMENT $D WOULD RESULT IN ATTEMPTS TO DRIVE THE MOVABLE ELEMENT ALONG X OR Y AXIS AT A VELOCITY GREATER THAN THE OBTAINABLE, THE TIME INTERVALS FOR EXECUTIVE OF A BLOCK OF DATA ARE LENGTHENED SO THAT MOTIONS OF THE ELEMENT TAKE PLACE WITH THE MAXIMUM VELOCITY ALONG ONE OF THE AXES.

Inventors

• 👤 Darwin H Bingham Jr

Bibliographic Details