Method for producing an active part for a rotating electric machine
Described is a method for producing an active part for a rotating electric machine. The method includes providing a core for the active part and shaped conductors which are inserted into the core. The core has an end side and a further end side situated opposite the end side. The core has slots arranged in a circumferential direction in which the shaped conductors are arranged. The shaped conductors extend from the end side to the further end side, and each shaped conductor has a free end which protrudes at the end side and has an end face. Two end faces are joined together and welded by means of a laser beam, which is guided along a pattern having a trajectory.
1 . A method for producing an active part for a rotating electric machine, comprising:
providing a core for the active part and shaped conductors which are inserted into the core, wherein the core has an end side, a further end side which is situated opposite the end side and a plurality of slots which are arranged in a circumferential direction and in which the shaped conductors are arranged, wherein the shaped conductors extend from the end side to the further end side and each have a free end which protrudes at the end side and has an end face;
joining in each case two of the end faces to one another, so that the two end faces form a pair, wherein an edge of the end face of a respective shaped conductor consists of an inner edge portion and an outer edge portion, wherein the inner edge portion of the end face of one shaped conductor of a respective pair runs along the inner edge portion of the end face of the other shaped conductor of the pair and a boundary region runs between the inner edge portions; and
welding a respective pair of the end faces by a laser beam which is guided along a pattern having a trajectory over an area on the edge of which the outer edge portions lie and which includes the boundary region,
wherein an energy of the laser beam on the area is input into the respective pair by guidance along the pattern asymmetrically with respect to a line of symmetry which runs along the boundary region or perpendicularly to the boundary region.
2 . The method according to claim 1 , wherein the pattern further has a second trajectory.
3 . The method according to claim 2 , wherein the second trajectory runs asymmetrically to the first trajectory with respect to the line of symmetry.
4 . The method according to claim 2 , wherein the pattern further has a third trajectory which surrounds the first and the second trajectory or runs between the first trajectory and the second trajectory without overlapping.
5 . The method according to claim 4 , wherein the third trajectory has a start point and an end point and runs in a straight line between the start point and the end point or is a closed trajectory.
6 . The method according to claim 2 , wherein the first trajectory runs in a circular, oval or rectangular manner, and/or the second trajectory runs in in a circular, oval or rectangular manner.
7 . The method according to claim 2 , wherein the first trajectory and the second trajectory run on different sides of the line of symmetry and on different sides of a line which divides the line of symmetry perpendicularly and centrally.
8 . The method according to claim 6 , wherein the second trajectory runs in a closed manner over both sides of the line of symmetry and the first trajectory runs, diagonally, within the second trajectory and intersects the line of symmetry.
9 . The method according to claim 2 , wherein
the first trajectory and the second trajectory each have a start point and an end point, which is different therefrom, and describe an arched curve of a circle, an arc of an ellipse, a parabola or a hyperbola, on the area or have or consist of a first to third straight portion, wherein the first straight portion extends from the start point, the third straight portion extends in the direction of the end point and the second straight portion connects the first straight portion to the third straight portion.
10 . The method according to claim 9 , wherein the first trajectory and the second trajectory run with mirror-image symmetry with respect to a line shifted in parallel in relation to the line of symmetry.
11 . The method according to claim 2 , wherein an energy intensity of the laser beam along the first trajectory is greater than or lower than along the second trajectory.
12 . The method according to claim 2 , wherein the trajectory has a start point and an end point, which is different therefrom, and intersects the line of symmetry between the start point and the end point at least four times.
13 . The method according to claim 12 , wherein the second trajectory has a start point and an end point, which is different therefrom, and runs in a straight line, entirely on one side of the line of symmetry, and the pattern further has a third trajectory which has a start point and an end point, which is different therefrom, and runs, in a straight line, entirely on the side of the line of symmetry on which the second trajectory does not run.
14 . The method according to claim 1 , wherein the active part is a stator or a rotor of the rotating electric machine.