GB1273579A - Temperature control system - Google Patents

Abstract

1,273,579. Moulding glass. CORNING GLASS WORKS. 14 Nov., 1969 [22 Nov., 1968; 12 May, 1969; 11 June, 1969], No. 55794/69. Heading C1M. In a machine for forming articles from heated or molten material, which sequentially moves each of a plurality of moulds through a plurality of positions, e.g. a glass forming machine, subsequent to the material forming positions a temperature detecting station is provided for adjusting a supply of cooling fluid to each mould which carry identification signals. These activate a store carrying desired temperature signals individual to each mould, which are compared with sensed temperature signals thus producing an adjustment signal to vary cooling fluid flow. The store may be a digital computer or a bank of storage amplifiers. If the temperature of any mould is too low or high, a correction signal is added to the set point signals to adjust the cooling fluid during the next cycle. In a practical embodiment the machine has a rotary table 11 carrying moulds 10, e.g. four in number which are identified by a pin 26 and/or 27 or neither engageable with pneumatic eyes PE1, PE2 which actuate air operated relays PS1, PS2 selecting one of a plurality of manually set resistors 61-64 the voltage from which is compared with the amplified voltage from a pyrometer 21, sensing mould temperature, in a comparator 57 which through an electropneumatic transducer 58 and actuator 76 positions, proportionately to the error signal, a piston-rod 76 driving a rack 83 engaging with gear teeth formed on a spline 84, which through a friction or magnetic clutch 86 energizable through a machine timing contact (TDC), Fig. 4 (not shown), momentarily engages with a member 46 and hence rotates a valve 16 controlling air flow. In the period during movement of the table and moulds, the clutch is not actuated, and through relay contacts the input to comparator 57 is shunted. This actuates piston-rod 76 into mid-position. In a modification shown in Fig. 5, subsequent to adjustment to the mid-position and before re-engagement of the clutch, the piston-rod is further adjusted in accordance with signals sequentially selected and stored in signal storage amplifiers SA1-SA4 input signals to which are fed during the previous cycle in dependance of any divergence between the sensed temperature relative to the set point. The input signal may be any determined fraction of such divergence. Cooling air is fed past each mould dependant on the setting of valves 16 during the whole of the table rotation hence each temperature measurement adjusts the cooling rate during the next revolution and has little effect on an article already formed and completed.