Stator for use in electric rotating machine
A stator for use in an electric rotating machine is provided which includes a stator winding wound through slots of a stator core. The stator winding is made up of a plurality of conductor segments connected together. Each of the conductor segments includes an in-slot portion disposed inside one of the slots and out-slot portions extending from the in-slot portion outside at least one of the ends of the stator core. Ends of the out-slot portions are joined together to form the stator winding. The joints of the ends of the out-slot portions have a given pattern of texture formed on surfaces thereof and coated with an insulating material. The pattern of texture enhances the adhesion of the insulating coatings to the surfaces of the joints and ensures the stability in electric insulation of the joints.
1. A stator for use in an electric rotating machine comprising:
a stator core with ends opposed to each other in an axial direction thereof, the stator core having a plurality of slots formed therein;
a stator winding wound through the slots of the stator core, the stator winding being made up of a plurality of conductor segments connected together, each of the conductor segments including an in-slot portion disposed inside one of the slots and out-slot portions extending from the in-slot portion outside at least one of the ends of the stator core, ends of the out-slot portions being joined together to form the stator winding, joints of the ends of the out-slot portions having a given pattern of texture formed on surfaces thereof; and
insulating coatings formed on the pattern of texture on the surfaces of the joints of the ends of the out-slot portions.
2. A stator as set forth in claim 1 , wherein the ends of the out-slot portions are made of copper oxide, the pattern of texture on the surfaces of the joints of the out-slot portions being formed by welding the ends to create blow holes.
3. A stator as set forth in claim 1 , wherein the pattern of texture on the surfaces of the joints of the out-slot portions is formed by pressing a knurling tool with webbing irregularities against the surfaces of the joints to transfer a pattern of the mesh-shaped irregularities onto the surfaces of the joints.
4. A stator as set forth in claim 1 , wherein the pattern of texture on the surfaces of the joints of the out-slot portions is formed by shot-blasting the surface of the joints.
5. A stator as set forth in claim 1 , wherein the pattern of texture on the surfaces of the joints of the out-slot portions is formed by a plurality of grooves formed in the surfaces of the joints.