872 THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1954 



Typical installation of wire straightening and molding machines. 



The final embodiment of the molding machine is sho^^^l in Fig. 9. 

 The A\dre straightener included in the photograph is positioned a short 

 distance from the molding machine to allow straightened mre to form a 

 partial loop between the two. This permits the mres to leave the straight- 

 ener at a constant speed from a fixed position and to enter the die at 

 intervals controlled by the molding cycle and move vertically with 

 the opening and closing motions of the lower half of the die. The straight- 

 ening machine is started and stopped by an electrical control which 

 assures the desired size partial \nre loop at all times. 



PHENOLIC RESIN PREFORMS 



To operate on an automatic basis, it is important to have the molding 

 compound in such form that it can be handled easily and that the charges 

 are of uniform weight and size. This is done by compressing the bulky 

 granular compound as received from suppliers into small carefully di- 

 mensioned cylinders or "preforms". Mechanical presses, capable of 

 turning out preforms in multiple at each stroke, are used at Hawthorne 



