Semi-automatic machines for chill casting hollow parts such as pistons

Claim 1

A SEMI-AUTOMATIC MACHINE FOR CHILL CASTING PARTS COMPRISING A CAVITY WHICH HAS A NARROWED PORTION REQUIRING THE USE OF A CORE FORMED OF A PLURALITY OF MOVABLE CORE ELEMENTS SEVERALLY EXTENDED BY AN ACTUATING WHEEL AND MAINTAINED SPACED FROM ONE ANOTHER DURING CASTING AND CLOSE TO ONE ANOTHER DURING STRIPPING, AN EXTENDABLE RETRACTABLE KEY ADAPTED TO TRANSLATE LONGITUDINALLY OF ITSELF BETWEEN AN OPERATIVELY ENGAGED POSITION BETWEEN THE MUTUALLY SPACED CORE ELEMENTS DURING THE CASTING OPERATION AND AN INOPERATIVE POSITION OF RETRACTION THEREFROM DURING THE STRIPPING OPERATION BEING MOUNTED ON A SLIDABLE KEY SUPPORT THROUGH THE AGENCY OF WHICH THE MOVABLE PART OF RECIPROCATING TRANSLATIONAL MOTION ENGENDERING DRIVE MEANS IS ADAPTED TO PUSH SAID KEY FROM ITS RETRACTED POSITION OT ITS ENGAGED POSITION, SAID MACHINE BEING CHARACTERIZED IN THAT SPREADER MEANS ARE PROVIDED FOR BIASING DURING MACHINE OPERATION SAID CORE ELEMENTS TOWARDS THEIR MUTUALLY SPACED POSITION AND IN THAT IN RESPECT TO EACH OF SAID ELEMENTS THERE IS PROVIDED A BELLCRANK LEVER FULCRUMED INTERMEDIATE ITS ENDS ON THE MACHINE IN SUCH MANNER THAT ONE OF ITS ARMS EXERTS PRESSURE AGAINST SAID ACTUATING HEEL OF THE CORRESPONDING CORE ELEMENT IN THE SENSE OF MOVING THE SAME TOWARDS THE OTHER CORE ELEMENTS WHEN ON REACHING THE END OF THE RETRACTING STROKE SAID KEY SUPPORT EXERTS A FORCE ON THE OTHER BELLCRANK ARM THROUGH THE MEDIUM OF A DRAW-LINK COMMON TO ALL THE BELL-CRANK LEVERS.