Automotive alternator stator assembly with rectangular continuous wire

1. A method of forming a stator core assembly for an electric machine of the type having a rotor assembly and a stator assembly, the stator assembly of the type having an annular core defining an outside diameter, an inside diameter, and a plurality of radially projecting winding slots opening to the inside diameter but terminating short of the outside diameter, the core further defining a lead side and an opposite non-lead side, the method comprising the steps of:

a) providing two electrical conductors designated as conductor A and conductor B,

b) winding the conductors into the winding slots where:

n=number of phases of the stator core assembly,

m=number of the winding slots in the stator core, with the winding slots numbered 1 through m,

L=number of radial layers of the conductors A and B in the winding slots, wherein L=1 is defined as a layer where conductors A and B are interleaved in the first and second outermost portions of the slots, L=2 is defined as a layer where conductor A and B are interleaved in the third and fourth outermost portions of the slots, and L=K is defined as a layer K where conductors A and B are interleaved in the 2 K and 2 K−1 outermost portions of the slots wherein K=1 for layer 1 which is the outermost layer and K=L being the innermost layer, by the following winding steps:

c) the winding including placing a first lead of conductor A into the slot number 1 with the conductor A first lead extending from the stator lead side end,

d) the winding including placing a first lead of the conductor B into slot number n+1 with the conductor B first lead extending from the stator lead side end,

e) the winding including shifting the conductor A to the slot number n+1 thereby forming an end loop on the non-lead side end and lying in the slot number n+1 radially shifted inwardly from the conductor B and located in the second outermost radial portion of the slot,

f) the winding including shifting the conductor A to the slot number 2 n +1 and lying in slot number 2 n +1 radially shifted outward to lie in the outermost radial portion of the slot,

g) the winding including shifting the conductor B to the slot number 2 n +1 thereby forming an end loop on the non-lead side and lying in the slot number 2 n +1 radially shifted inwardly from the conductor A and located in the second outermost radial portion of the slot,

h) the winding including shifting the conductor B to the slot number 3 n +1 and lying in slot number 3 n +1 radially shifted outward to lie in the outermost radial portion of the slot,

i) repeating winding steps e) through h) for every n+1 slot, through slot number m+1−n for conductor A, and slot number 1 for conductor B, thereby forming a first layer K=1,

j) the winding including shifting the conductor A from slot M+1−n radially inward into the third outermost portion of slot number 1 and shifting the conductor B from slot number 1 radially inward into the third outermost portion of slot number n+1,

k) repeating steps e) through j), thereby forming additional layers through L wherein the conductors A and B of each layer K will lie in 2 K−1 and 2 K outermost portions of the slot for e) through I) and in 2 K+1 outermost portion of the slot for j) and k), and deleting step j) for the innermost layer K=L.

2. The method of forming a stator core assembly for an electric machine according to claim 1 , further including:

completing the current phase winding by extending conductor A from the radial innermost portion of slot m+1−n on the lead side end, thereby defining a conductor A second lead, and extending conductor B from the radial innermost portion of slot 1 on the lead side, thereby defining a conductor B second lead.

3. The method of forming a stator core assembly for an electric machine according to claim 2 , further including:

completing the stator winding by repeating winding steps c) through l) for each phase 2 through n, wherein each phase is shifted by one slot from the previous phase.

4. A method of forming a stator core assembly for an electric machine according to claim 1 , wherein the conductors are of the type having a substantially rectangular cross-sectional shape.

5. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the conductors are of the type having a substantially square cross-sectional shape.

6. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the provided conductors, including any insulation on the conductors, have a width of a dimension to be closely received by the winding slots including any insulation on the slots.

7. A method of forming a stator core assembly for an electric machine according to claim 1 wherein n=3.

8. A method of forming a stator core assembly for an electric machine according to claim 1 wherein n=6.

9. A method of forming a stator core assembly for an electric machine according to claim 1 wherein L=3.

10. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the two conductors A and B are series connected.

11. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the two conductors A and B are parallel connected.

12. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the two conductors A and B are formed to a shape to be placed into the winding slots before being placed into the winding slots.

13. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the two conductors A and B are interleaved prior to the step of being placed into the winding slots.

14. A method of forming a stator core assembly for an electric machine according to claim 1 wherein the two conductors A and B are interleaved by alternating the front and rear positions in a predetermined pitch of slots of the two conductors, excluding three consecutive slots in each radial shift area, prior to the step of being placed into the winding slots, wherein at the radial shift areas, one conductor is placed in front of the other conductor for three consecutive slots.

15. A method of forming a stator core assembly for an electric machine according to claim 13 wherein the layers of the conductors are wound in a linear fashion such that layer 2 is aligned and continuous with layer 1 , layer 3 is aligned and continuous with layer 2 , and layer K+1 is aligned and continuous with layer K, wherein the layers are placed into the slots beginning with layer number 1 toward a rear portion of the slots and is inserted in one rotational direction such that layer 2 lays radially inward of layer 1 , layer 3 lays radially inward of layer 2 , and layer K+1 lays radially inward of layer K.

16. A method of forming a stator core assembly for an electric machine according to claim 14 wherein the end loops of conductors A and B of each phase are twisted to interleave conductors A and B of all the phases prior to insertion into the core.