Die casting apparatus

Claim 1

A PISTON CONSTRUCTION COMPRISING A CYLINDRICAL BODDY HAVING AN EXTERNAL RADIAL SHOULDEER AT ONE END; A CONNECTING ROD RIGIDLY SECURED TO SAID BODYD IN AXIAL ALIGNMENT THEREWITH, AN END PLATE HAVING ANN OUTSIDE DIAMEETER SUBSTANTIALLY THE SAME AS SAID OUTSIDE DIAMETER OF SAID SHOUDLER, MEANS FOR REMOVABLY SECURING SAID END PLATE TO THE SIDE ONE END OF SAID BODY REMOTE FROM SAID SHOULDER AND IN AXIAL ALIGNMENT WITH SAID BODY, A PISTON RING ASSEMBLY HAVING A GREATER DIAMETER THAN SAID BODY INCLUDING AN AXIALLY REMOVABLY ANNULAR CARRIAGE ONN SAID BODY AND SPACED THEREFROM BETWEEN SAID SHOULDER AND SAID END PLATE, A CIRCUMFERENTIAL GROOVE IN SAID CARRIAGE, A SEAL RING IN SAID GROOVE, SAID ANNULAR CARRIAGE HAVING PARTIALLY SPHERICAL AXIAL END SURFACES, SAID END PLAT E HAVING PARTIALLY SPHERICAL SURFACES ENGAGING ONE OF SAID PARTIALLY SPHERICAL CARRIAGE ENDS, SAID SHOULDER HAVING PARTISPHERICAL SURFACES ENGAGING THE OTHER OF SAID PARTIALLY SPHERICAL CARRIAGE ENDS WHEREBY SAID CARRIAGE IS CAPABLE TRANSVERSE OR RELATIVE AXIAL MOVEMENT.