A laser welding method is usable to weld a material containing copper as a main component. The laser welding method includes heating the material by irradiation with a first laser light and welding the material by irradiation of a portion, which has been irradiated with the first laser light, of the material with a second laser light with which an energy absorption rate of the copper contained in the material increases by an increase in a temperature of the material. A wavelength of the first laser light is 400 nm to 470 nm.

The present invention provides a motor including a stator around which coils are wound, a rotor disposed inside the stator, a rotating shaft coupled to the rotor, insulators positioned between the coils and the stator and including outer circumferential surfaces around which the coils are wound, and a motor housing configured to accommodate the insulators, wherein wings configured to arrange the coils are connected to the outer surfaces of the insulators, and an accommodation space configured to accommodate the wings is formed inside the motor housing.

A stator includes a stator core and a stator winding installed in the stator core. The stator winding has multiple conductor segments in which a conductor is coated with an insulating film 35. The conductor segment includes an exposed portion in which the conductor is exposed at its leading end, and a covered portion in which the conductor remains coated with the insulating film. At a coil end section of the stator winding, the exposed portions of different conductor segments are engaged with each other. A depression as a plastic deformation formed by crushing at least a part of the insulating film is provided at an edge of the covered portion of the conductor segment, located closer to the leading end of the conducting wire, thereby Providing a stator capable of suppressing peeling off of the insulating film and ensuring insulation reliability of the stator winding.

A stator and a manufacturing method thereof is enabled to easily determine the quality of welding produced between conductors. The stator includes a stator core and a stator winding installed in the stator core. The stator winding is configured by including multiple flat conductor segments in which conductors 34 are coated with insulating films 35, respectively. At a leading end of each of the conductor segment, an exposed portion 33 is formed in which the conductor is exposed. At a coil end section of the stator winding, a pair of exposed portions of different conductor segments are joined together by laser welding. A collective conductor width in a joining direction in which exposed portions join with each other is smaller at a laser irradiation incidence side, which is a side of the exposed portions receiving laser irradiation than that at a side opposite to the laser irradiation incidence side.

A manufacturing method of a stator according to the disclosure includes a clamping process of clamping, among coil ends of segment coils assembled into a stator core, a pair of coil ends adjacent to each other in a circumferential direction, by a clamp jig that presses the pair of coil ends in the circumferential direction, and a welding process of welding the coil ends exposed through an opening portion provided in the clamp jig. The clamp jig includes a pressuring structure that increases a pressing force in a direction away from weld faces of the coil ends welded in the welding process, the pressuring structure being provided on at least one of sideward pressing faces that come into contact with side faces of the coil ends that are provided orthogonal to the weld faces.

A stator has a stator coil provided on an annular stator core. The stator coil is formed of electrical conductor wires each including an electrical conductor and an insulating coat. Each of the electrical conductor wires has a pair of exposed portions where the electrical conductor is exposed from the insulating coat and a covered portion where the electrical conductor is covered with the insulating coat. The pair of exposed portions are formed respectively at opposite end portions of the electrical conductor wire. The covered portion is formed at other portions of the electrical conductor wire than the end portions. At a coil end part of the stator coil, each corresponding pair of the exposed portions of the electrical conductor wires are welded together and each of the covered portions of the electrical conductor wires includes a coat-removed portion where the insulating coat is locally removed from the covered portion.

The invention relates to a method for producing an arrangement for a plug-in coil of an electrical machine, comprising the steps of: providing a core with slots; providing coil elements which are rod-shaped and have a proximal end and a distal end; inserting the coil elements into the slots from an end side of the core with the distal end at the front in such a way that the proximal end is arranged in the region of the end side and the distal end is arranged in the region of an opposite end side of the core or adjacent to it; and producing a respective jointed connection for the distal ends or the proximal ends of a first coil element and of a second coil element with an associated first connecting element on the opposite end side or the end side of the core, wherein, here, before joining between the respective joining partners, specifically the distal end or the proximal end of the first coil element and a first joining section of the first connecting element and also the distal end or the proximal end of the second coil element and a second joining section of the first connecting element, a connection is formed in each case, with which the relative position of the joining partners in relation to one another is defined. The invention further provides an arrangement for a plug-in coil of an electrical machine.

A method for stripping a rod-shaped conductor using laser radiation is provided. The rod-shaped conductor includes an electrically conductive core and a coating that is at least partially transparent to the laser radiation. The method includes traversing the conductor for a first time with at least one laser beam to at least partially reduce transparency of the coating, and traversing the conductor for a second time with the at least one laser beam to at least partially reduce adhesion of the coating.

This method of manufacturing a stator includes a step of removing insulating coatings on first surfaces of lead wire portions that are surfaces to be welded, and a step of welding together the first surfaces by a green laser with the insulating coatings on the first surfaces being removed and with insulating coatings on second surfaces opposite the first surfaces being unremoved.

An object of the present invention is to suppress variations in an angle of a shoulder part of a segment coil to improve easiness in inserting segment coils in a stator core.

A stator of an electric motor according to the present invention includes a stator core 12 in which a plurality of slots 12a are formed, and a plurality of segment coils 11 of U shapes inserted respectively in the plurality of slots 12a.

The segment coil 11 includes a shoulder part 11a and a shoulder part 11b that are bent to form a U shape. In a front view of the U shape, a press mark 100a is formed on the shoulder part 11a and on the shoulder part 11b, the press mark being a dent sinking in a front-to-rear direction, from a front surface of the shoulder part 11a and from a front surface of the shoulder part 11b. The press mark 100a is formed also on a back surface of the shoulder part 11a and on a back surface of the shoulder part 11b.