CARD TRANSLATOR FOR NATIONWIDE DIALING 1079 



tabs. As a precautionary measure, tools have been made available that 

 afford adequate protection of the cards while they are being handled. 

 One of these tools is for inserting one card at a time in the card stack. 

 The other tool, which is illustrated by Fig. 22, is used when it is neces- 

 sary to handle a number of cards at a time. It will be noted that it affords 

 protection for the tabs. This tool may be used for loading and unloading 

 all of the cards of a compartment of the card cage in a single operation. 

 The cards, after bulk removal, may be conveniently stored in one of the 

 card compartments of the test set illustrated by Fig. 16. 



CODE SELECT AND CARD SUPPORT BARS 



The load on a single bar may be as much as 24 pounds. Deflection 

 due to loading has to be maintained at a minimum because any deflec- 

 tion reduces the effective height of the light tunnels through the card 

 stack. However, the bars have to be light because high-speed operation 

 is required. In addition, they have to be wear-resistant because of the 

 many millions of operations to which they are subjected annually. These 

 are difficult conditions to meet but a satisfactory solution was found 

 by providing deep section die cast magnesium bars that are fitted with 

 details made from suitable wear-resistant materials at the point of 

 loading. Such bars, as components, are depicted by Fig. 29, in which 

 the bottom bar is of the card support type. The other three bars shown 

 are code select bars. They illustrate the different terminations that are 

 required by the mounting arrangement employed. 



The spacing is Jf g" to affect alignment with the tabs of the cards. 

 This close spacing makes it necessary to vary the amount of overhang 

 beyond the up and down stops so that the associated solenoids may be 

 mounted in staggered array and thus their diameter need not be unduly 

 restricted. Despite the variations in conditions it was made possible to 

 use but a single mould by casting the ends of the bars of uniform cross- 

 section and long enough to accommodate the longest extension required. 

 For those cases requiring lesser extension, the bars are cut off to suit. 

 The bars are designed so that they may be used end-for-end and, there- 

 fore, although five mounting positions have to be taken care of, the 

 three different end terminations illustrated suffice. It may be noted that 

 the bars during fabrication are straightened if necessary by bumping. 

 In this way, the necessity for side surface machining is obviated and in 

 consequence the side skin of the bars is maintained intact which enhances 

 stiffness. 



The weight is only 115 grams each and yet their deflection under the 

 heaviest working load that may be developed is but 0.003" which is 



