Method and one-piece tool assembly for producing a stator for an electrical machine

1. A method for producing a stator comprising the steps of:

providing a two-layer winding ( 12 ) having a radially outer layer ( 10 ) and a radially inner layer ( 11 );

providing plurality of electrical conductor elements ( 6 , 7 ), a portion of the plurality of electrical conductor elements ( 6 , 7 ) being part of the radially outer layer ( 10 ), and a portion of the plurality of electrical conductor elements ( 6 , 7 ) being part of the radially inner layer ( 11 );

providing a plurality of conductor ends ( 23 ), one or more of the plurality of conductor ends ( 23 ) being part of a corresponding one of the plurality of electrical conductor elements ( 6 , 7 );

providing a laminated core having an end face and a plurality of slots;

arranging each of the plurality of electrical conductor elements in one or more of the slots of the laminated core;

providing a tool having a plurality of receiving regions arranged in a ring on an end face of the laminated core; and a relative arrangement of the receiving regions along a circumferential direction of the ring corresponds to a relative end position for one or more of the plurality of conductor ends of the conductor elements of the radially outer layer for interconnection with one or more of the plurality of conductor ends of the plurality of electrical conductor elements of the radially inner layer;

providing a plurality of through-openings, each of the plurality of through-openings being part of a corresponding one of the plurality of receiving regions;

providing a positioning process, the positioning process comprising the steps of:

moving the tool into a first turning position;

inserting each of the plurality of conductor ends of a first group of the conductor elements of the layer into one of the receiving regions;

turning the tool into at least one further turning position; and

inserting each of the plurality of conductor ends of a further group of the conductor elements of the layer into one of the receiving regions until the plurality of conductor ends of all the plurality of conductor elements of the layer are in the relative end position in relation to one another.

2. The method of claim 1 , further comprising the steps of:

providing at least one coil;

providing a normal region, a portion of the plurality of conductor ends being located in the normal region;

providing a plurality of groups each of the plurality of groups being part of the at least one coil;

providing one of the plurality of groups to further comprise the conductor ends of the normal region;

providing one of the plurality of groups to further comprise the plurality of conductor ends for interconnecting turns of the at least one coil;

providing one of the plurality of groups to further comprise the plurality of conductor ends for coil terminals of the at least one coil.

3. The method of claim 1 , further comprising the steps of:

providing each of the plurality of electrical conductor elements to further comprise a straight bar;

inserting the plurality of electrical conductor elements through a corresponding one of the plurality of slots when inserting each of the plurality of conductor ends into a corresponding one of the receiving regions.

4. The method of claim 3 , further comprising the steps of firing the plurality of electrical conductor elements into the slots.

5. The method of claim 1 , further comprising the steps of

providing a twisting process;

providing a plurality of conductor parts, each of the plurality of conductor parts being part of a corresponding one of the plurality of electrical conductor elements ( 6 , 7 );

completing the twisting process after the positioning process;

bending the conductor ends of one of the radially outer layer or the radially inner layer in the twisting process by relative turning of the tool with respect to the laminated core and at the same time bringing together of the tool and the laminated core, so that each of the plurality of conductor parts of the plurality of conductor elements of the outer layer and each of the plurality of conductor parts of the plurality of conductor elements of the inner layer that protrude out of the laminated core are bent along the circumferential direction, so that each of the plurality of conductor parts have a skewing region, all of which have the same skewing angle with respect to the end face of the laminated core.

6. The method of claim 5 , further comprising the steps of:

providing a first tool for the radially outer layer ( 10 )

providing a second tool for the the radially inner layer ( 11 )

carrying out the twisting process in opposite circumferential directions for the radially outer layer ( 10 ) and the radially inner layer ( 11 ) so that the projecting conductor parts of one of the radially outer layer ( 10 ) or the radially inner layer ( 11 ) and the projecting conductor parts of the other of the radially outer layer ( 10 ) or the radially inner layer are transposed with one another.

7. The method of claim 5 , further comprising the steps of exerting an ejecting force through each of the plurality of through openings to each of the plurality of conductor ends after the twisting process is completed.

8. The method of claim 1 , further comprising the steps of providing radially inner slot openings of the plurality of slots, each of the radially inner slot openings have in the circumferential direction a slot width which is less than a dimension of the plurality of conductor elements that are respectively arranged in the plurality of slots.

9. A tool arrangement for producing a stator for an electrical machine, the tool arrangement comprising:

at least one tool for a radially outer layer or a radially inner layer ( 11 ) of a two-layer winding;

a ring;

a plurality of receiving regions arranged in the ring for inserting a plurality of conductor ends of a plurality of conductor elements, and a relative arrangement of the plurality of receiving regions along a circumferential direction of the ring corresponds to a relative end position for the plurality of conductor ends of the plurality of conductor elements for interconnection one or more of the plurality of conductor ends of the plurality of conductor elements of the radially inner layer or the radially outer layer of the two-layer winding;

a holding device for holding a laminated core in such a way that an end face of the laminated core is facing the at least one tool; and

a plurality of through-openings, each of the plurality of through-openings being part of a corresponding one of the plurality of receiving regions;

a movement device, wherein with the laminated core arranged in the holding device, and for one of the radially outer layer or the radially inner layer, each of the plurality of conductor ends of the plurality of conductor elements are respectively arranged in one of the receiving regions in each case in a positioning process and the at least one tool is moved into a first turning position, and each of the plurality of conductor ends of a first group of the plurality of conductor elements is respectively inserted into one of the receiving regions, then the at least one tool is turned into at least one further turning position and each of the plurality of conductor ends of a second group of the plurality of conductor elements in each case is respectively inserted into one of the receiving regions, until the plurality of conductor ends of all the plurality of conductor elements have been respectively inserted into a receiving region and are in a relative end position in relation to one another.

10. The tool arrangement of claim 9 , wherein the movement device is designed such that, after the positioning process, the at least one tool for each of the radially outer layer or the radially inner layer and the laminated core are brought together in a twisting process and, during the twisting process, the at least one tool is turned in relation to the laminated core, so that each of the plurality of conductor elements are uniformly bent by the same skewing angle with respect to the end face.

11. The tool arrangement of claim 10 , wherein an ejecting force is exerted through each of the plurality of through openings to each of the plurality of conductor ends after the twisting process is completed.