Method and apparatus for die casting

Claim 1

DIE CASTING APPARATUS COMPRISING, IN COMBINATION, A MOLTEN METAL RESERVOIR; A NOZZLE COMMUNICATING WITH SAID RESERVOIR AND HAVING A DISCHARGE APERTURE; A MOUTH PLATE HAVING ONE SURFACE IN HEAT CONDUCTIVE CONTACT WITH SAID NOZZLE DISCHARGE APERTURE AND HAVING AN OPENING THERETHROUGH IN ALIGNMENT WITH SAID APERTURE; A METAL MOLD IN HEAT CONDUCTIVE JUXTAPOSED CONTACT WITH THE OTHER SURFACE OF SAID PLATE AND FORMED WITH A MODL CAVITY HAVING AN INJECTION OPENING ALIGNABLE WITH SAID PLATE OPENING; A RECIPROCABLE EJECTION PIN MOVABLE THROUGH SAID INJECTION OPENING AND CAVITY TO EJECT A CASTING FROM SAID METAL MOLD; A GUIDE MOUNTING SAID METAL MOLD FOR MOVEMENT ALONG AND IN SUCH JUXTAPOSED CONTACT WITH SAID OTHER PLATE SURFACE BETWEEN AN INJECTION POSITION, IN WHICH SAID INJECTION OPENING IS ALIGNED WITH SAID PLATE APERTURE, AND AN EJECTION POSITION IN WHICH SAID INJECTION OPENING IS ALIGNED WITH SAID EJECTION PIN; MEANS OPERABLE WHEN SAID METAL MOLD IS IN THE INJECTION POSITION TO MOVE MOLTEN METAL FROM SAID RESERVOIR INTO SAID NOZZLE AND TO EJECT THE MOLTEN METAL FROM SAID NOZZLE, THROUGH SAID DISCHARGE APERTURE AND SAID PLATE APERTURE INTO SAID MOLD CAVITY; A PUSH ROD RECIPROCABLE AXIALLY IN SAID NOZZLE AND IN SAID DISCHARGE APERTURE AND SAID PLATE OPENING, SAID PUSH ROD HAVING AN OPERATIVE POSITION IN WHICH AN OUTER CONICAL PORTION THEREOF ENTERS AND BLOCKS SAID DISCHARGE APERTURE AND A CYLINDRICAL EXTENSION THEREOF EXTENDS THROUGH SAID PLATE OPENING TO A POSITION WHEREIN ITS OUTER SURFACE IS SUBSTANTIALLY FLUSH WITH THE PLANE OF JUXTAPOSITION OF SAID PLATE AND SAID MOLD, AND A RETRACTED POSITION IN WHICH SAID OUTER CONICAL PORTION AND CYLINDRICAL EXTENSION OF SAID PUSH ROD ARE WITHDRAWN FROM SAID DISCHARGE APERTURE AND SAID PLATE OPENING; MEANS OPERABLE TO MOVE SAID PUSH ROD TO ITS RETRACTED POSITION DURING INJECTION OF MOLTEN METAL INTO THE MOLD CAVITY; MEANS OPERABLE, RESPONSIVE TO COMPLETION OF THE INJECTION OF MOLTEN METAL INTO SAID MOLD CAVITY, TO MOVE SAID PUSH ROD TO ITS OPERATIVE POSITION TO EXCLUDE MOLTEN METAL COMPLETELY FROM SAID DISCHARGE APERTURE AND SAID PLATE OPENING; MEANS OPERABLE, WHEN SAID METAL IN SAID MOLD CAVITY IS COOLED AND PARTLY SOLIDIFIED, TO MOVE SAID MOLD ALONG AND IN THE JUXTAPOSED CONTACT WITH SAID OTHER PLATE SURFACE TO THE EJECTION POSITION; AND MEANS OPERABLE, WHEN SAID MOLD IS IN THE EJECTION POSITION TO RECIPROCATE SAID EJECTION PIN THROUGH SAID INJECTION OPENING AND CAVITY TO EJECT THE SOLIDIFIED CASTING FROM SAID METAL MOLD.