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THE BELL SYSTEM TECHNICAL JOURNAL, JULY 1954 



Fig. 17 — Indexing and shearing section of automatic die. 



other, there is some tendency for it to warp upon eoohng. To prevent 

 this, when the die is closed the plastic embedded wire assemblage is 

 clamped against spring loaded steel pads operating between water cooled 

 plates and retained in this position during the next molding cycle. The 

 closing of the die also causes the cull to be sheared off, Fig. 16. This 

 waste material slides down a chute for removal from the press. A locat- 

 ing stop is built into this section of the die to establish the proper spac- 

 ing for inserting a new progression of wires through the die should such 

 action become necessary as when wire from new spools must be placed 

 in the dies. This locating stop can be used also as a check at any time to 

 determine whether the parts are being indexed the proper distance. 



INDEXING AND SHEARING 



The mechanism for indexing the continuous strands of wire through 

 the die is located beneath and parallel to tracks built into the last die 

 section to accommodate and guide them. It is driven by a timer con- 

 trolled pneumatic cylinder to which feed heads are attached by a yoke. 

 The feed heads reciprocate on rails beneath the guide track and trans- 

 mit their motion to the ladderlike train of assemblies by a spring loaded 

 dog which engages the resin blocks on the forward stroke. The return 

 stroke is carried out after the press is closed. 



