Electrolytic shaping apparatus and method

Claim 1

IN THE METHOD OF ELECTROLYTICALLY SHAPING A CONTOURED SURFACE ON AT LEAST ONE WORKPIECE TO CONFORM IN SIZE AND SHAPE TO A MASTER, COMPRISING MOVING THE ACTIVE FACE OF A HOLLOW ELECTRICALLY CONDUCTIVE ELECTRODE TOWARD A CONDUCTIVE MASTER, PUMPING AN ELECTROLYTE INTO THE WORK GAP BETWEEN THE ELECTRODE AND THE MASTER UNDER A HIGH PRESSURE AND AT HIGH VELOCITY, PASSING A LOW VOLTAGE, HIGH DENSITY DIRECT ELECTRIC CURRENT BETWEEN THE ELECTRODE AND THE MASTER IN A SENSE TO MAKE THE ELECTRODE ANODIC, RELATIVELY TRANSVERSELY MOVING THE ELECTRODE AND THE MASTER ACROSS THE LONG DIMENSION OF THE ELECTROLYTE PASSAGE IN THE ELECTRODE AND WITHIN THE TRANSVERSE DIMENSION OF THE ELECTRODE WHILE RELATIVELY MOVING THE ELECTRODE AND MASTER TOWARD EACH OTHER, THEREBY TO CONTOUR THE ACTIVE FACE OF THE ELECTRODE, THEREAFTER SUBSTITUTING A WORKPIECE FOR THE MASTER, REVERSING THE POLARITY OF THE ELECTRIC CURRENT SO THAT THE WORKPIECE IS ANODIC AND THE ELECTRODE CATHODIC TO PASS A LOW VOLTAGE, HIGH DENSITY DIRECT CURRENT BETWEEN THE WORKPIECE AND THE ELECTRODE, RELATIVELY MOVING THE ELECTRODE AND THE WORKPIECE TOWARD EACH OTHER WHILE PUMPING THE ELECTROLYTE INTO THE WORK GAP BETWEEN THE ELECTRODE AND THE WORKPIECE, AND SIMULTANEOUSLY TRANSVERSELY MOVING THE ELECTRODE AND THE WORKPIECE WITH THE SAME MOVEMENTS AND AT THE SAME RATE AS THE ELECTRODE AND THE MASTER WERE TRANSVERSELY MOVED, THEREBY TO FORM A CONTOURED SURFACE ON THE WORKPIECE SUBSTANTIALLY IDENTICAL WITH THE CONTOURED SURFACE ON THE MASTER.