Abstract: Tooling includes an inflatable arbor for forming a backdraft cavity in a foundry sand core. A core handling device includes an inflatable arbor, similar to the one used for forming the backdraft cavity in the sand core, whereby the lifting device arbor, when in its deflated state, may be inserted into the backdraft cavity of the sand core and then inflated to grip and become locked to the sand core.

Abstract: In an apparatus for the compaction of foundry sand by the impact of pressurized gas on the foundry sand as filled into a flask over a pattern plate with a pattern therein, a specially designed diaphragm is used to get an even and constant hardness of the mold in every horizontal plane thereof and/or to put an end to the formation of shear cracks in the mold between different parts of the volume of the sand. This diaphragm is placed over the so far uncompacted surface of the foundry sand and it has a permeability to gas varying with the height of the sand to be compacted so that such permeability is less in the parts with high and/or plateau-like pattern contours than in parts where there is no pattern on the pattern plate.

Abstract: A molding machine has a base, a pattern provided with a plurality of vent bores formed therethrough and mounted on the base, a molding flask arranged to be combined with the pattern, an upset frame superposed to the molding flask, cover means for making an airtight contact at its lower end with the upper surface of the base, molding flask or of the upset frame. Further, compressed air supplying means are provided for supplying compressed air into the closed space defined by the pattern, the molding flask and the upset frame, the space being filled with molding sand. The cover means include a cylindrical member and cover member. The cylindrical member slidably fits to the outside of the cover member in a telescopic manner, and is provided at its lower end with an inwardly projected flange.

Abstract: In a method of forming foundry sand moulds employing a cold-setting sand mixture pressed around a pattern by the use of pneumatic pressure acting on a flexible diaphragm, the sand is formed into a horizontal layer of approximately uniform thickness in a frame of which the bottom wall is formed by the diaphragm, the pattern is then pressed into that layer of sand, causing the diaphragm to bulge downwards, then the gas pressure (conveniently air pressure) is applied to compact the sand, which thereupon sets to allow separation of the resultant mould body from the diaphragm and pattern. During the initial formation of the layer the diaphragm can be supported by a further, stronger diaphragm, which is perforated to allow the gas pressure through, or by a rigid pad, or both.

Abstract: Moulding flask adapted to be used in a process for forming a mould comprising steps of disposing, at the opening of the moulding flask, a pattern having a shield membrane of synthetic resin on the outer surface thereof, filling the space defined between the moulding flask and the pattern with particulate filler material such as sand, and applying negative pressure to the filler material so that the filler material is subjected to an external pressure to make a mould, said moulding flask having at least one surface on an intermediate partition surface formed by an impervious resilient membrane which is supported by a support member whereby, when the filler material is subjected to the negative pressure, the external pressure is applied to the resilient membrance which then presses the filler material so as to enhance compacting of the mould thus producing a strong and precise casting mould.