10G2 THE BELL SYSTEM TECHNICAL JOURNAL, NOVEMBER 1952 



Fig. 32 — AJ relay with twenty-four make contacts. 



additional operations and (2) the greater flexibility of the wire spring- 

 terminals caused some diflaculty for the operator so that some increase 

 resulted in the time required to make a connection. 



The wrapping tool was first visualized as a simple, trigger-operated 

 hand tool, later as an air or electrically operated tool and still later as a 

 combination tool to do additional operations including cutting and 

 skinning the connecting wire. 



Although the wrapping tool was developed to solve a problem which 

 arose in the development of the wire spring relay, it was first applied in 

 commercial practice by the Western Electric Company for wiring to the 

 flat spring relay terminals. Wrapped connections are now used exten- 

 sively with these terminals, resulting in an improved product at a lower 

 cost. In making wrapped connections to either flat or round terminals, 

 it was the expectation that tinned terminals and wire would be used 

 and soldered together to give a stable, low resistance junction. More 

 recently, however, it has been possible to show that soldering is not 

 required if certain definite dimensional conditions are satisfied by the 

 terminal and the wrapping tool. Solderless wrapped connections will be 

 described in detail in a separate paper. 



