GB328576A - Improvements in or connected with metal casting machines - Google Patents

Abstract

328,576. Fry's Metal Foundries, Ltd., and Farlie, J. B. Jan. 29, 1929. Metal-pots.-The level of the molten metal 1 in a melting-pot b of a type or other casting machine is kept constant by an electrical device, in circuit with the metal, which automatically controls the feeding of an ingot a. Contacts f<1>, f<2>, normally engaged by the metal 1, are fixed to the pot b and complete a circuit through an electro-magnet or solenoid g arranged to hold a switch g<2> open. When the level of the metal falls the circuit is broken at f<1>, f<2> , and a spring, not shown, closes the switch g<2> thereby completing a circuit through a magnet h. This pulls down the armature h<1> and closes a switch h<3>, h<4> to make a circuit through g, thereby breaking the circuit through h at g<2> and allowing a spring k<1> to return the armature h', thus breaking the circuit at h<3>, h<4> and allowing the switch g<2> to close again. This sequence of operations continues as long as the circuit is broken at f<1>, f<2> and the oscillation of the armature h<1> is transmitted to a lever k having offset teeth k<2>, k'. The ingot a is suspended by a cord c and drum e slidable axially on rods r' of a gear q which is connected, through a pinion p, ratchet clutch r, worm n, and wheel m, to an escapement wheel i engaged by one of the teeth k<2>, k<3>, so that as these oscillate vertically the wheel i can rotate, one tooth at a time, and the ingot is lowered. The drum e is screwed on its support so that as it rotates it moves axially. The clutch r allows the cord to be wound up by a squared spindle q<2> when it is necessary to attach another ingot. In modification the contacts are not employed but the wires are connected one to the pot b and the other to the ingot a.