GB616656A - Improvements relating to the die casting of metals - Google Patents

Abstract

616,656. Casting-machines. BIRMINGHAM ALUMINIUM CASTING (1903) CO., Ltd., FAIRBAIRN, H., and BAKER, W. A. Sept. 18, 1946, No. 27968. [Class 83 (i)] Pouring-apparatus.-In the die casting of metals, the metal is heated in a furnace which is moved into relation with the injection chamber of a casting machine, and maintained in that relation so that it can be subjected to air or gas pressure in order to discharge metal from the furnace chamber into the injection chamber in advance of the means for forcing the charge of metal into the die. The crucible 25 of the furnace 24 is divided into two portions, 34, 35, with a communication 36 between them and provided with a charging aperture 39 including means for introducing air or gas above the metal in the chamber 34 to build up pressure for discharging metal through the removable nozzle 45, of metal or suitable refractory material, which in the discharge position engages a recess 46 in the wall of the injection chamber, from which recess a passage leads into the interior of the chamber. An aperture 52 in the wall of the injection chamber enables the operator to observe the rise of the metal into the chamber, from which it is forced into the die by a hydraulic ram. The furnace 24 is movable on rollers 29 along rails 27 and is propelled towards and away from the casting machine by a pinion 32 engaging a rack 33, being located in position by a tongue on the closure of the chamber 35 which engages between collars 47 on a tie-bar 48, and being drawn into, and held in, position by eyebolts 50. It is preferred to maintain a constant level of molten metal in the chamber 35 during casting, by the use of an adjustably loaded pressure valve. In modifications, the removable nozzle 45 may be heated and the injection chamber may be water cooled. Specification 577,389 is referred to.