Armature for rotary electric machine
An armature for a rotary electric machine includes: a core that includes a plurality of teeth that are arranged at a predetermined pitch in a circumferential direction; and a plurality of edgewise coils that are configured by winding a rectangular conductor wire into an edgewise winding, the plurality of edgewise coils each include rectilinear portions and coil end portions that are arranged radially, and that are each linked by bent portions, the rectilinear portions are arranged radially on circumferential side portions of the teeth so as to be gradually further away from a central axis of the teeth from a tip end of the teeth toward a root, and radially adjacent portions of the rectangular conductor wire are configured such that bulging portions that arise due to compressive stresses resulting from bending at inner peripheral side portions of the bent portions do not face each other.
1. An armature for a rotary electric machine comprising:
a core that includes teeth that are respectively arranged to extend radially at a predetermined pitch in a circumferential direction; and
edgewise coils that are configured by winding a rectangular conductor wire that is coated with insulation for a plurality of turns into an edgewise winding,
wherein:
each of the edgewise coils includes rectilinear portions and coil end portions that are arranged radially, each of the rectilinear portions and the coil end portions being linked by bent portions;
the rectilinear portions are arranged radially on circumferential side portions of the teeth to be gradually further away from a central axis of a respective one of the teeth from a tip end of the respective one of the teeth toward a root of the respective one of the teeth; and
radially adjacent portions of the rectangular conductor wire are configured such that bulging portions that arise due to compressive stresses resulting from bending at inner peripheral side portions of the bent portions do not face each other.
2. The armature for a rotary electric machine according to claim 1 , wherein each of the teeth have a trapezoidal cross sectional shape perpendicular to an axial direction in which a circumferential width widens gradually from the tip end of the respective one of the teeth toward the root of the respective one of the teeth, the rectilinear portions being arranged radially alongside circumferential side surfaces of the teeth.
3. The armature for a rotary electric machine according to claim 2 , further comprising insulating end plates that are disposed on two axial end surfaces of each of the teeth, and that have an outer peripheral surface shape that contacts inner peripheral side surfaces of the coil end portions and the bent portions that are arranged radially.
4. The armature for a rotary electric machine according to claim 3 , wherein recessed grooves that have a groove direction in a radial direction are recessed to extend from a first radial end to a second radial end of a bottom surface of the insulating end plates, and
the armature further comprises auxiliary cores that are disposed to protrude from two axial end surfaces of the core and to be housed inside the recessed grooves.
5. The armature for a rotary electric machine according to claim 2 , further comprising insulating sheets that are disposed to surround an outer periphery of columns of the rectilinear portions that are arranged radially alongside the circumferential side surfaces of the teeth.
6. The armature for a rotary electric machine according to claim 5 , further comprising a varnish that is impregnated into the edgewise coils.
7. The armature for a rotary electric machine according to claim 3 , further comprising insulating sheets that are disposed to surround an outer periphery of columns of the rectilinear portions that are arranged radially alongside the circumferential side surfaces of the teeth,
wherein the edgewise coils are concentrated winding coils, and are molded integrally onto the teeth together with the insulating end plates and the insulating sheets, using an insulating resin.