THE SINGLE-PHASE MOTOR. 



tive conductors per pole n, then we have for the induction in the air- 

 gap: 



n . im V/2 

 (I7) <*= 1.6. A 



In this formula im is the effective value of the magnetizing cur- 



\ 



FIG. 30. 



rent, while A is the air-gap. If & is the width of the iron of the 

 motor in cm, / the pole-pitch, then we have, 



08). 



. <B 



* = , 



Instead of a coefficient of 2.22 we get, as will easily be seen, a co- 

 efficient of 1.85; therefore, we have the formula: 



(19) e = 1.85 . ~ . z . * . lo- 8 



Secondly Fig. 31 shows this case. For the induction formula 

 (16) holds good. 

 The number of lines of induction is equal to 



(20) 



as may be seen at a glance. 



* = b . t . <B, 



61 



