| 摘要 |
<p><PICT:1107471/C1/1> A method of moulding an article wherein a charge of hot glass is placed in the cavity of a mould and a plunger is pressed into the cavity to form an article comprises, maintaining a predetermined difference between the mould and plunger temperatures so that, when the plunger is withdrawn from the mould cavity the moulded article stays with the hotter of the plunger and mould. Preferably the article is caused to stay with the mould. A thermocouple placed in the mould senses the temperature of the mould and feeds its information into a function controller and thence into a mould controller. In this latter there is a manually set point which indicates the desired mould temperature. Another thermocouple in the plunger sense the plunger temperature which information is fed into a plunger controller. This latter also receives a signal from the function controller (see Fig. 1) dependent upon the signal from the mould thermocouple. Thus when the mould controller receives a signal which shows a derivation from the set point it operates a valve to increase or decrease cooling air to the mould accordingly. Simultaneously a comparative signal is sent to the plunger controller which also operates a valve to increase or decrease cooling air to the plunger to thus maintain a predetermined temperature difference between the mould and the plunger. The article thus pressed may be a dinner plate. Pyrometers may be used in place of thermocouples.</p> |
