GB930127A - Improvements in and relating to control device for a molten metal pouring ladle in acentrifugal machine - Google Patents

Abstract

930,127. Centrifugal casting-machines. COMPAGNIE DE PONT-A-MOUSSON. Feb. 10, 1961 [March 25, 1960], No. 4994/61. Class 83 (1). In a centrifugal casting machine, the ladle 1, which permits several sequential pouring steps after filling, is tilted by an hydraulic jack V, supplied with hydraulic fluid by two electric pumps P 1 , P 2 , working in parallel, one pump P, for the slow pouring and tilting and the other, P 2 , for short, quick tilting or impulse, there being an independent electric supply to each pump, a photo-electric cell 49 which on the appearance of molten metal at the lip of the ladle actuates means J to stop discharge from the impulse pump P 2 into the jack, a number of rheostats R 1 -R 6 connected in the electric supply to the pouring pump P 1 which may be individually adjusted to effect speed regulation of the pump for a corresponding fraction of the tilting angle of the ladle, and a cam 8 which rotates with the ladle and renders operative each of the said rheostats in turn. In a particular embodiment each rheostat R 1 -R 6 corresponds to the pouring of one pipe. When casting is started by manual movement of the valves S 1 , S 2 to the left of the position shown in Fig. 1, the mould 13 moves towards the left and the ladle is rapidly tilted under the combined action of the pumps P 1 , P 2 . When molten metal is sighted at the pouring lip by the photo-electric cell 49, the valve J is actuated and the pump P 2 discharges to exhaust pipe 39 and the ladle continues to tilt to pour under the action of pump P 1 only. Closing of the switch i 1 by the cam 8 over the angle of tilt x 1 corresponding to the angle of tilt to discharge metal for one pipe has placed ghe rheostat R 1 in the pump circuit to give a predetermined pump speed. Meanwhile, the mould has moved to its extreme left-hand position by the piston 18 and then commences it's return to the right while the poured metal in the trough 11 is cast over its entire length. Shortly before the mould reaches its extreme right-hand position the valves S 1 , S 2 are manually moved to the right, setting the jack V to discharge so that the ladle tilts back to bring the molten metal below the pouring lip. The cell 49 is no longer energized and valve J opens and the valves S 1 , S 2 are moved manually to the central position to hold the ladle. The next pouring step is then started by moving the valves S 1 , S 2 to the left, and the pouring of the second pipe commences, with the initial tilting by the two pumps until the cell 49 is energized, and the rheostat R 2 placed in the pump circuit by closing of the switch i 2 by the cam 8. After six pipes have been east, a switch c 2 is closed, which opens the circuit of pump P 1 and actuates a valve K to allow the jack V to discharge to the tank B and the ladle to return to its original position. If any pipe is found to be overweight or underweight the corresponding rheostat may be adjusted by a hand wheel 6 to alter the pump speed during the corresponding pouring step. As each rheostat is operative an indication is given by an associated lamp L 1 -L 6 controlled by switches j 1 -j 6 actuated by the cam 8. Each rheostat may be associated with only a portion of the angle of tilt for one pipe, e.g. the angle of tilt x 1 -x 6 may be sufficient for only three pipes, there being then two rheostats associated with each pipe.