摘要 |
The barrel has a number of independently controlled resistance heaters with their conductors packed in insulation; these heaters are pressed down on to the elasticating barrel by means of split collars and tangential grips. Holders engage the device to carry the plasticising unit when it is being changed; another device cuts off the unit in a stable equilibrium position when disconnected from the injector. The resistance heaters are spiral, flat and tubular and under the pressure of the collars; at the ends of the spirals where they are free from heater windings the individual wires are brought out and they are covered with a U-shaped protective section. This section is a support member. |