Patent GB-190507147-A (GB)
Title: Improvements in or relating to Sand-moulding Machines.
Inventor: BOULT ALFRED JULIUS
Filed: 1905-04-04
Granted: 1906-04-04
Abstract: 7147. Boult, A. J., [Soc. Deville]. April 4. Moulding ; castings.- Plant for moulding large objects, such as boilers, comprises means for charging the moulding- boxes, for compressing the sand, withdrawing the pattern, assembling the mould, ejecting the casting, and returning the sand through cooling, moistening, and screening apparatus to the supply hopper. Hoppers 2, Fig. 2, discharge sand into the moulds situated on trucks on rails 1. Upper and lower pressure heads are closed on the moulds and the sand is compressed. After casting, the trucks are moved to discharge the sand into the hoppers 12, Fig. 3, through coarse gratings 13 on which, Figs. 3 and 4, the lumps are broken up and screened. The trucks then proceed to a cooling - chamber. The sand is transferred by bucket elevators 11 to transverse conveyers 15<a> which discharge the sand at 14<a> while treated with a water spray actuated by compressed air. The moistened and renovated sand passes through a reciprocating screen 14<b> to a hopper 14, which supplies the feeding hoppers 2 by bands 16 driven as required by clutch-contiolled drums. The truck 17, Fig. 7, has a central recess to receive the lower flask 18, which is fitted with loose rings c, d, according to the shape of the pattern. Two sets of guide-shafts 24, 25, for raising and lowering the flasks, have screw threaded parts which engage nuts in lugs on the upper and lower flasks and are rotated by a system of shafts and gearing from a belt pulley as controlled by disengaging bevels. The truck is traversed on the rails by hand-operated spur gearing. The compressing-apparatus comprises an upper member 58 pivotally mounted in a swinging balanced frame and a lower member 48 carried by a piston-rod a<1>. These members are connected during compression by columns 8 and cottars. The platform 48 is heavily ribbed and carries a large number of pins b to stay the lower flask 18. An annular channel 50<1> receives compressed air at 51 for delivery to tubes 52 carried by a ring 49 and surmounted by caps covered with rubber or flexible cloth 9. Elastic packing 50 is placed between the ring 49 and the platform. A similarly arranged apparatus 53 closes the centre of the mould. A flexible, elastic lining 61 in the member 58 compresses the sand above the mould. The ring c has a recess 47 which is rammed with sand beforehand to ensure the perfect formation of the flanged rim of the boiler. The admission to and exhaust from the flexible compressors is controlled by a single valve. During the entry into and withdrawal from the mould of the parts 9, 53, the air pipes are connected to a vacuum chamber, to facilitate the operation. After compression, the platform 48 is lowered and the member 58 is raised, the lower flask and the mould part is lowered by means of the screwed shafts 25, a light truck is passed under the pattern, which is then disconnected from the upper flask, and the latter is raised by the shafts 24. The parts are then returned, and form between them the mould ready for casting. A similar procedure is followed in removing the casting, the truck being then situated over the part of the pit which contains the elevator 11.