1120 THE RELL SYSTEM TECHNICAL JOURNAL, SEPTEMBER 1954 



Fig. 8 — Molded wire assemblies for a 30-contact relay. 



this design will remain tight under widely varying atmospheric con- 

 ditions. 



In the design of the new relay considerable attention was given to 

 manufacturing control of tolerances, with reduced assembly and ad- 

 justment costs as an objective. The molding process provides dowels 

 for aligning the four layers of contact springs, trunnion supports to 

 locate the single wires, and control grooves in the single wire subas- 

 semblies to align the twin wires. These features provide accurate registra- 

 tion for mating contacts, for the location of wire subassemblies relative 

 to other relay parts and for the pretensioned restoring spring which in 

 turn locates the actuating card in relation to the operating contacts. 

 The card determines contact separation of all twin moving contacts 

 in relation to their respective single stationary contacts. Due to these 

 controls, and because the pre-deflected twin wire springs require no 

 adjustment of contact force, no factory adjustments are anticipated 

 except on relays which fall outside acceptable limits for back tension 

 or contact gauging (or follow) as assembled. If necessary, therefore, the 

 restoring spring may be adjusted to control the armature back tension. 

 Contact gauging may be controlled if required by independent mass 

 adjustment of the single wire contact rows. Fig. 1 1 shows this operation 

 being performed by bending the bracket arm using a tool designed for 

 this purpose. The mass adjustment feature is expected to simplify field 

 maintenance practice. 



