Patent GB-726540-A (GB)
Title: Metal casting machine
Inventor: SCHUMACHER RAYMOND CARL
IPC: B22D15/02
Filed: 1953-01-16
Abstract: 726,540. Casting-machines. BOHN ALUMINUM & BRASS CORPORATION. Jan. 16, 1953, No. 1381/53. Class 83 (1). A casting-machine comprises at least one mould assembly formed of two movable mould halves and a collapsible assembly of a centre core section and two side core sections, an extractor device movable from a discharging position to a position over the mould assembly, a spray device movable from an inoperative position to a position over the mould assembly and electrically controlled means subject to manual operation of a switch to effect an automatic cycle of operations and, subject to manual operation of a second switch upon completion of the first cycle, to effect a second automatic cycle of operations; said first cycle including energizing a timing device to time a metal setting period, moving the extractor device over the mould assembly, opening the mould halves, collapsing the core assembly, extracting the casting, moving the extractor and casting to the discharge position, moving the spray device into position over the core assembly, and spraying cooling fluid thereon, energizing a timing device to control the period of spraying and returning the spray device to the inoperative position, said second cycle including closing the mould halves and releasing the casting from the extractor at the discharging position. Moulds.-The moulds A, B, for casting pistons, and which are filled by hand, each comprise a head block and halves 10, 11 mounted on slides 12, 13 which are movable inwardly and outwardly by hydraulic cylinders 22, 23, through lost-motion devices each comprising a pushpull rod 30, Fig. 6, carrying yokes 31, 32, the yoke 31 carrying a core-pin 33. The operating rod 27 has an enlarged head 35 fitting into the yoke 32 and the yokes are spaced apart by an amount greater than the thickness of a plate 29 fastened to the slide 12, 13 so as to provide the desired amount of lost motion. Cooling fluid may be supplied to the head blocks and the mould halves through supply lines 52, 52a, outlets 52b being provided. Cores.-Each metal core pin 33 projects through a side wall of the mould and meets the centre core assembly. Each core pin includes a central tapered portion 36, Fig. 8, and complementary side portions 37, 38 held in position by a bushing 40, Fig. 6, and a pin 39 fixed in the portion 36 engages in elongated slots in the outer portions so that on opening the mould the first part of the motion pulls outwardly the. portion 36 and causes the portions 37, 38 to slide down the tapered portion and collapse inwardly away from the wall of the wrist pin boss. Each central core assembly is of metal and comprises three sections, the centre section being movable downwardly by a cylinder 43 and allowing the side sections 44, 45 to move inwardly under the influence of cylinders 50, 51 to allow the casting to be removed. Casting composite articles.-When the machine is used for casting strut pistons of the type described in Specification 429,145, [Group XXVI], the side sections are provided with means such as permanent magnets for holding the steel struts in position. Cooling cores.-A carrier 78 carries spray heads 74 and is actuated by an air cylinder 82 into and out of operating position, the operations of the machine being timed so that the spray headers reach the operating position after the castings have been removed and the cores reassembled for the next casting operation. Extracting castings.-The extractor comprises two heads 54 on an arm 55 rotatable by a cylinder 62 about a vertical axis in bearings carried by a slide vertically movable by a cylinder. The arm may be adjusted angularly on the shaft 56 by screws 218. Each head, Figs. 11, 12, comprises gripping fingers 67 forming the lower parts of bell cranks whose upper parts 69 extend into the groove of an operating spool 71 actuated by an air cylinder 73. The fingers engage lugs 224 on the casting. Operation. The electrical control system comprises timing devices and limit switches actuated by movement of the various mould and core-moving cylinders, the extractor heads and arm 55, and the spray carrier, to ensure that the correct sequence of operations is carried out, failure at any one stage resulting in the sequence being halted until attended to.