CONSTRUCTION OF SQUIRREL CAGE ARMATURES 103 



Now we come to cases where the rotor conductors are of 

 rectangular cross section. 



Fig. 115 illustrates a good method, which is similar to that 



B 



FIG. 112. End Rings used by Alioth Co. 



illustrated in Fig. 106. Here the end ring has a number of 

 slots milled out from the outer circumference, into which the 

 bars emerging from the slots fit and are sweated. The slots may 

 be cut on a milling machine with a 

 divided head, and, provided this item 

 of the process can be executed fairly 

 cheaply, the whole method is com- 

 paratively inexpensive. 



The method employed by the 

 Westinghouse and Thomson Houston 

 Companies, is to screw the ring on to 

 each bar individually, as shown in ta ^*s2Jt?SuiS 

 Fig. 115. This makes a rather longer Aktiebolaget. (Old Type.) 

 job than the method of Fig. 114, but 



it renders the end rings absolutely safe against coming away from 

 the bars, as may occur where solder alone is relied on at the joints. 



The photograph of a rotor carried out on this plan is shown in 

 Fig. 116. The construction of the rotor spider and end flanges is 

 here worth noticing. The spider follows the lines of Fig. 104, 



