Production of foundry cores

Claim 1

A cold-box core-making machine for producing resin-bonded foundry cores comprising in combination a hopper for containing core sand and having in its base two valve-controlled outlets; two separate mixers connected to receive controlled amounts of sand from respective hopper outlets; means for supplying a metered quantity of resin to one of the mixers; means for supplying a metered quantity of hardener to the other mixer; a final mixer connected to receive the output of said separate mixers and which produces a homogeneous final mix, a source of compressed air connected to said final mixer; a blow-head connected to receive compressed air from said source and resinfree sand from a supply of sand; a delivery manifold; power operated means effective to move said delivery manifold from a first position in which it receives said final mix from said final mixer to a second position beneath said blow-head; first time-controlled valve means for controlling the flow of air from the reservoir to blow the mix from said final mixer into said delivery manifold when said delivery manifold is in said first position; a core-box; means for clamping the delivery manifold between the blow-head and said core-box when said delivery manifold is in its second position; and further time-controlled valve means effective to deliver air from the reservoir to the blow-head after the core-box has been clamped to the delivery manifold.