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ARMATURE CONSTRUCTION 



ponent coil of the triple coil separately upon a fibre-lined wooden 

 form. These separate coils are afterwards assembled together to 

 form the triple coil during the insulating operation. This winding 

 form has the exact contour of the finished coil, and is fastened to 

 a lathe head : the wire being wound directly off the reel on to this 

 form, the shape of the coil being preserved up to the time of its 



sMcc of 3 wes 



FIG. 340. Winding Triple Coil. 



being assembled together with the other two by means of metal 

 clips, as previously described. 



Fig. 341 shows the arrangement of the form, which consists of 

 a wooden block made in two halves. 



A type of metal form suitable for this class of coil is shown in 



Fro. 341.- Winding Block for Wire Coils. 



Fig. 342. This form is designed to produce factory coils ensuring 

 an absolute fit the one into the other ; it is made of special light 

 and non-corrosive tough metal. The outer half can be released 

 and the coil removed without the use of nuts or wrenches, which 

 renders it quick in operation. For winding, the form is mounted 

 simply on a winding head. 



Having now dealt with the construction of winding forms and 

 methods of shaping coils in general, and considered the application 

 to two typical cases, we shall proceed to give some photographs of 



