GB855495A - Improvements in die casting machines - Google Patents

Abstract

855,495. Casting-machines. GOLDHAMER, W. M. June 12, 1959, No. 20187/59. Class 83 (1). A die-casting machine has a separate metal cooling member 24, 25 secured to each die member 6, 7 at least one of said cooling members being movable into engagement with or away from the other cooling member during movement of the die member to which it is attached, a passageway 27a, between the engaged metal cooling members connected to a vacuum duct 28 or exhaust and the die cavity 16, and means for cooling the said cooling members to solidify metal in said passageway before the metal solidifies in the die cavity. The cooling members have chill blocks 46, 47, Figs. 5, 6, with corrugated surfaces which define the tortuous passageway 27a and coolant channels C. The member 25 includes an ejector plunger 57, Fig. 6, which is actuated by striking the machine frame as the dies open, to engage the solidified metal in the passageway and eject it and the attached casting. A baffle 52 and filter 54 prevent particles of metal entering the vacuum system. The cooling members are insulated from the dies by air pockets 41. Solenoid valve 31 in the vacuum system is actuated by a switch 34 on die closing to apply vacuum which is restricted by an orifice 30. A solenoid valve 35 is actuated by timer T to apply full vacuum. A passageway 39<1> opposite the passageway 27a is connected to pressure recording and indicating apparatus 29. The injection plunger 58 is longitudinally slotted and is capable of limited rotation about its longitudinal axis by a cylinder 80, Figs. 10, 11, controlled by a valve 82 actuated by the timer T. The arrangement is such that after die closing and with the plunger retracted and in the position shown in Fig. 10, the application of the partial vacuum to the die sucks up a charge of molten metal from the container 21 into the injection chamber. After a timed delay the cylinder 80 turns the injection plunger to the position shown in Fig. 11, whereat the slot 61 connects the metal feed pipe 20 to atmosphere to allow the metal in the pipe to return to the vessel 21, the solenoid valve 35 is actuated to apply full vacuum and then the cylinder 67 forces the injection plunger forward.