Patent GB-1413909-A (GB)
Title: Automatic casting equipment
IPC: B22D35/00
Filed: 1973-06-01
Abstract: 1413909 Foundry ladles CHRYSLER CORP 1 June 1973 [29 Sept 1972] 26319/73 Addition to 1381647 Heading F4B [Also in Division B3] Pouring apparatus for filling a mould with molten metal comprises a pouring ladle 121 121 carried on a rotatable and swingable arm 120 arranged to move the ladle between a horizontal position for filling it and a tilted pouring position, the arm rotating means including an electric motor and a rotary switch initiating and controlling various operations of the apparatus in dependence on the rotation of the ladle. As described in Specification 1,381,647 the pouring apparatus is mounted between two similar piston casting machines 113, 114 each of which has a loader 126 for placing reinforcing struts in the mould and an unloader for removing pistons from the moulds and transferring them to racks 129 for cooling. In the position shown the ladle is filled with a measured volume of molten metal to be poured into one of the moulds. The arm 120 is swung by a traverse drive unit 119 consisting of a motor 119a, a reducing gear 119b, a chain-driven rotary cam switch assembly 119c controlling the motor and a vertical axle 119d on which is mounted the swinging head. The ladle can be raised and lowered by a linkage system 118 between a lower table 118c mounted on the axle 119d, and an upper table 118b. The linkage system comprises links 118a actuated by an electric motor 118d driving arm 118g through a gear-box 118f. Abutments on arms 118a operate limit switches LS1 and LS2 when the table is fully raised and lowered respectively. The ladle is tilted by rotation of arm 120 controlled by tilting mechanism 124. This consists of a motor 124a and a gearbox 124b, the output shaft 124c of which is coupled to the arm 120. Shaft 124c is also coupled by a chain drive to cam switch assembly 124d consisting of a number of cams 124g, Fig. 3, and cam switches CS1B-CS4B. The switches are connected in a control circuit to relays and potentiometers to. govern the speed of the motor so that the ladle pours in a predetermined controlled manner. The pouring rate may be initially fast to establish flow into the mould, then slow until near the end of the pour, then fast to fill the riser. After filling one mould the ladle swings back to the middle position for a fresh charge of metal to be poured into the other mould. The control circuit is in the form of a ladder and each step follows automatically upon the previous step. If for any reason a step is delayed, a timing device gives a warning. The cycle is started by starting one of the pistonmoulding machines which begins by placing struts in the mould. The ladle is in the filling position and the piston-moulding machine selected takes control of the pouring apparatus, the other piston-moulding machine being locked out. As soon as the struts are placed the furnace fills the ladle with a predetermined amount of metal. When filling is complete and the strut loader signals that it is out of the way, the ladle is swung to the pouring position. When the ladle is in position and the mould signals that it is closed, the linkage mechanism lowers the mould to be close to the mould, the limit switch LS2 initiating the tilt of the ladle to pour the metal. When the ladle is empty of molten metal the skin-catcher 124h is projected under the ladle to catch the skin which falls out at full tilt. The piston-moulding machine then begins a cooling, mould-opening and piston-removing cycle while the other machine places struts and the pouring apparatus repeats under the control of the other piston-moulding machine. A complete cycle is described step-by-step with reference to the ladder circuit (Fig. 12, not shown).