Formation of a multi-lobed winding for the stator of an alternator

Abstract

Methods and apparatus are provided for forming a multi-lobed winding for the stator of an alternator, particularly those for use in the automotive field and of the type comprising turns defining a star-shaped configuration having a plurality of radial lobes alternated with hollows.

I claim:  
     
         1 . Apparatus that forms a multi-lobed winding, said winding having a plurality of radial lobes alternated with hollows, the apparatus comprising: 
 a rotating unit that winds a wire clockwise to form a first polygonal coil and winds said wire counterclockwise without cutting said wire to form a second polygonal coil, said rotating unit comprising a wire engaging element that intercepts said wire to form a loop when rotation of said rotating unit is reversed; and    pushing members carried by the rotating unit to push sides of each said polygonal coil radially inward to form said multi-lobed winding; wherein:    said second coil of said multi-lobed winding is axially superimposed on and angularly shifted relative to said first coil of said multi-lobed winding, and    said loop follows an annular path matching a profile of said first coil for one part and a profile of said second coil for another part.    
     
     
         2 . The apparatus of    claim 1    wherein said wire engaging element is stationary while said rotating unit rotates.  
     
     
         3 . The apparatus of    claim 1    wherein said wire engaging element is radially movable relative to said rotating unit.  
     
     
         4 . The apparatus of    claim 3    wherein said rotating unit further comprises a plurality of forming elements around which polygonal coils are formed while said rotating unit rotates, said forming elements radially movable relative to said rotating unit, said wire engaging element connected to one of said forming elements.  
     
     
         5 . The apparatus of    claim 1    wherein said wire engaging element has a profile substantially corresponding to a profile of one of said lobes.  
     
     
         6 . The apparatus of    claim 1    wherein said multi-lobed winding has a plurality of lobe-hollow positions, each said lobe-hollow position comprising a lobe of one of said first and second axially superimposed coils and a corresponding hollow of another of said first and second axially superimposed coils, said multi-lobed winding having a start lead and a final lead positioned together at a same one of said lobe-hollow positions, said start lead and said final lead positionable by said apparatus at each of a plurality of said lobe-hollow positions.  
     
     
         7 . The apparatus of    claim 1    wherein said multi-lobed winding has a plurality of lobe-hollow positions, each said lobe-hollow position comprising a lobe of one of said first and second axially superimposed coils and a corresponding hollow of another of said first and second axially superimposed coils, said multi-lobed winding having a start lead and a final lead positioned together at a same one of said lobe-hollow positions, said same one lobe-hollow position adjacent a lobe-hollow position that includes said loop.  
     
     
         8 . A method of forming a multi-lobed winding, said winding having a plurality of radial lobes alternated with hollows, said method comprising: 
 forming a first polygonal coil with a rotating unit;    pushing sides of said first polygonal coil radially inward to form a first semi-phase of said multi-lobed winding;    forming a second semi-phase of said multi-lobed winding axially superimposed on and angularly shifted relative to said first semi-phase, said first and second semi-phases formed with a same uncut wire between said first and second semi-phases; and    bending said uncut wire between said first and second semi-phases to form a loop following an annular path matching a profile of said first semi-phase for one part and a profile of said second semi-phase for another part.    
     
     
         9 . The method of    claim 8    further comprising positioning start and final leads of said multi-lobed winding at any one of said lobes alternated with hollows.  
     
     
         10 . The method of    claim 8    further comprising positioning start and final leads of said multi-lobed winding at one of said lobes alternated with hollows that is adjacent another one of said lobes alternated with hollows that includes said loop.