Automatic electro-hydraulic tracer

Claim 1

CONTOURING APPARATUS FOR A MACHINE TOOL, ADAPTED TO HOLD A CUTTER, A PATTERN AND A WORKPIECE, COMPRISING: MEANS FOR FIXING SAID PATTERN RELATIVE TO SAID WORKPIECE; A TRACER HEAD FIXED RELATIVE TO SAID CUTTER; A LINEARLY VARIABLE DIFFERENTIAL TRANSFORMER IN SAID HEAD, INCLUDING A SINGLE LINEARLY DISPLACEABLE CORE EFFECTIVE TO VARY TRANSFORMER OUTPUT IN PROPORTION TO CORE DISPLACEMENT; A DEFLECTABLE STYLUS CARRIED BY SAID HEAD IN POSITION TO TRACE SAID PATTERN; MEANS ASSOCIATED WITH SAID STYLUS FOR DISPLACING SAID CORE IN PROPORTION TO DEFLECTION OF SAID STYLUS IN ANY DIRECTION RELATIVE TO SAID HEAD, THE CORE DISPLACEMENT CONSTITUTING THE SOLE MEANS RESPONSIVE TO STYLUS DISPLACEMENT WHEREBY TO VARY OUTPUT OF SAID TRANSFORMER A FIRST SLIDE, A SECOND SLIDE TRANSVERSE TO SAID FIRST SLIDE, FIRST AND SECOND FEED MEANS ACTUATING SAID FIRST AND SECOND SLIDES RESPECTIVELY TO ESTABLISH RECTILINEAR MOTIONS OF SAID PATTERN RELATIVE TO SAID STYLUS; FIRST AND SECOND FEED CONTROL MEANS FOR SAID FIRST AND SECOND FEED MEANS RESPECTIVELY; AN ELECTRICAL ENERGY SOURCE CONNECTED TO SAID TRANSFORMER AND SAID FEED CONTROL MEANS; MEANS FOR ESTABLISHING A PRESELECTED NULL CONDITION WITH SAID STYLUS CONTACTING SAID PATTERN, IN WHICH CONDITION SAID FIRST SLIDE IS AT REST AND SAID SECOND SLIDE IS IN MOTION AT A PRESELECTED MAXIMUM FEED RATE; AND ADDITIONAL CONTROL MEANS RESPONSIVE TO THE OUTPUT OF SAID TRANSFORMER EFFECTIVE TO SET SAID FIRST SLIDE IN MOTION AND SIMULTANEOUSLY REDUCE THE FEED RATE SAID SECOND SLIDE, THE EFFECT ON SAID SECOND SLIDE BEING A FUNCTION SOLELY OF THE OUTPUT AMPLITUDE.