ARMATURE LAMINATIONS 



51 



FIG. 46. Drawing showing Sheet punched for 

 Dovetail Notches and Slot for Segment Ends. 



The segment attachment comprises a sector of suitable form, 



which is guided by anti-friction rolls. The sheet to be cut is 



fastened to this sector 



and guided by it in a 



circular path past the 



cutters, the guiding rolls 



being near the cutters to 



prevent vibration. The 



same sector may be used, 



within certain limits, for 



varying radii, as the 



gauging parts may be 



fastened to adjustable 



arms, thus allowing work 



to be cut to any radius, 



with a limited number 



of sectors. 



The segments pre- 

 pared in this manner are 

 now ready to be slotted 

 and trimmed on the in- 

 side. The machine for 

 punching the slots is 

 illustrated in Fig. 48. 

 It has a guiding sector 

 similar to the segment 

 shear ; but this sector 

 has cut in its periphery, 

 notches in which a feed- 

 pawl, actuated -by the 

 press, engages, thus feed- 

 ing the sector with the 

 attached segment auto- 

 matically forward step 

 by step. A stationary 

 pawl locks the sector in 

 position before the 

 punch enters the 

 material, and the machine 

 stops automatically after the predetermined number of strokes 

 have been made. The die is so shaped that, while cutting 

 the slots, the .inner edge of the segment - is- simultaneously 

 TpK'jPLRTY Of ELECTRICAL LABOHATQHY, j 



FACULTY OF AfPLlEO SCItNCE. \ 



FIG. 47. Drawing showing result of Shearing 

 Operation. 



