248 



THE BELL SYSTEM TECHXICAL JOURNAL, JAXUARY 1954 



Table I — Cost per Unit of Various Kinds of Manufacturing 



Procedures 



Assuming for this hj^pothetical case that the values applying are 



ct = S0.05, 

 w = 100, 

 q ^0.2, and 

 V = 0.0006, 



then the cost of the resulting time is found in the last column of Table II. 



A summation of these two sets of cost penalties is given in Fig. 14, 

 which clearly shows that the ideal value of stroke is about 0.020", and 

 that that it va&y be permitted to xsny between the limits 0.015" and 

 0.025" without a serious economic penalty. 



In summary, a method has been indicated for deciding how important 

 it maj' be to build in, or omit, expensive design features which have an 

 effect on functioning time. An illustration has been given for an assumed 

 common control cirucit and an assumed change in a design feature of the 

 relay that importantly affects the time. The method, however, is equally 



Table II — Operating Times Corresponding to Various Spacings 



