Apparatus for closing, locking and opening a mold

Claim 1

MOLDING APPARATUS FOR REVERSELY CLOSING AND LOCKING A MOLD COMPRISING A FRAME HAVING A STATIONARY CASTING PROVIDED WITH AN OPENING THERETHROUGH, A FIXED MOLD PLATEN, TIE RODS CONNECTING THE CASTING AND PLATEN FIXEDLY TOGETHER WHICH ARE SEPARATELY SUBJECT TO A DIFFERENTIAL HEAT ELONGATED DURING A MOLDING OPERATION, A MOVABLE MOLD PLATEN MOUNTED SLIDABLY ON SAID TIE TODS, A SINGLE DRIVEN SCREW PASSING THROUGH SAID OPENING AND CONNECTED TO MOVE SAID MOVABLE PLATEN BETWEEN OPEN AND CLOSED MOLD POSITIONS, A NUT THREADED ON SAID SCREW AND ROTATIVELY MOUNTED TO TRANSMIT THRUST TO SAID CASTING ADJACENT TO SAID OPENING AND ARRANGED TO MOVE THE SCREW AXIALLY TO REVERSIBLE MOTOR MECHANISM CONNECTED TO ROTATE THE NUT RAPIDLY IN OPPOSITE DIRECTIONS, A REVERSIBLE HIGH PRESSURE HYDRAULIC MECHANISM COMPRISING A CYLINDER WITH END WALLS FORMING A PISTON CHAMBER AND A PISTON MOVABLE IN SAID CHAMBER BETWEEN SAID WALLS, ONE OF SAID WALLS BEING FIXED TO SAID MOVABLE PLATEN AND SAID SCREW BEING CONNECTED MEDIALLY TO SAID PISTON TO MOVE IT TO A DEFINITE STATIONARY POSITION WHEREBY ENGAGEMENT OF THE PISTON WITH EITHER OF SAID WALLS CAUSES THE MOVABLE PLATEN TO BE MOVED BY THE SCREW, SAID CYLINDER AND PISTON BEING RELATIVELY FLOATABLE AND PROVIDING ANGULAR COMPENSATION FOR A DIFFERENTIAL ELONGATION OF THE TIE RODS, MEANS INCLUDING A VALVE MECHANISM FOR INTRODUCING FLUID UNDER PRESSURE INTO SAID CYLINDER ON THE PLATEN SIDE OF THE STATIONARY PISTON TO MOVE SAID CYLINDER AND MOVABLE PLATEN TO LOCK THE MOLD AND ON THE OPPOSITE SIDE OF THE PISTON OT MOVE THE CYLINDER AND UNLOCK THE MOLD, AND REMOTE CONTROL MECHANISM GOVERNING THE NUT ROTATING MOTOR COMPRISING A LIMIT SWITCH ON THE FRAME OPERATED BY THE MOVABLE PLATEN WHICH IS ADJUSTABLY POSITIONED TO CAUSE THE SCREW TO COMPENSATE FOR VARIATIONS IN MOLD THICKNESS AND MOVE THE PLATEN TO A MOLD CLOSED POSITION.