Method and device for producing electric machine

Abstract

The invention relates to a method for manufacturing an electric machine, comprising the steps of: providing a stator body having stator slots; inserting conductor elements into the stator slots, forming unconnected winding heads; crossing the winding heads, the conductor ends of the winding heads being arranged in an annular monolayer, the conductor ends of the winding heads forming an annular arrangement of radial stack groups; according to the invention, the conductor ends of the winding heads are electrically connected, in particular welded, to produce the stator winding while forming joining partners joined to one another, each conductor end forming a joining partner with an adjacent conductor end in a radial stack of winding heads, the joining partners being arranged in an annular joining partner layer, according to the invention, the number of joining partners corresponds to half of a single layer, and the conductor ends of one of the joining partners, in particular all of the joining partners, are moved in the circumferential direction relative to the conductor ends of the adjacent joining partners after welding in order to eliminate an unpopular welded connection between two adjacent joining partners in the finished winding head.

Description

Technical Field

[0001] This invention relates to a method for manufacturing an electric motor. Furthermore, this invention relates to a manufacturing apparatus for manufacturing an electric motor based on this method. Background Technology

[0002] In the manufacture of electric motors used, for example, as drives in vehicles, rigid copper wires are used to create the stator, the ends of which are welded together so that current can flow through the stator in a meandering pattern. During the welding process, it is possible that too many wires are undesirably connected together. For example, it might be desirable to weld the ends of many adjacent wires into two separate joints, where undesirable weld joints are created between the joints, also known as paired composites. These composites must be removed before the next assembly step, for example by visual inspection of the welds, where paired composites are manually removed. Summary of the Invention

[0003] The method according to the invention allows for the reduction of manual work steps, such as visual inspection and / or manual finishing. This preferably allows for the realization of fully automated manufacturing equipment. Furthermore, the risk of an inspector failing to identify all paired composites is minimized or avoided. This reduces or avoids the risk of significant damage to the manufacturing equipment and the stator of the motor that may occur during subsequent manufacturing processes. In addition, manufacturing costs can be reduced.

[0004] A method for manufacturing an electric motor includes the following steps: First, a stator body having stator slots is provided or manufactured. The stator body is, in particular, a stator lamination assembly composed of stacked individual stator laminations. Conductor elements are inserted into the stator slots. The conductor elements are, in particular, U-shaped or I-shaped conductor leads, which are particularly advantageously coated with an insulating varnish. By inserting the conductor elements into the stator slots, at least one unconnected winding head is formed on at least one end side of the stator body.

[0005] The conductor ends of the corresponding unconnected winding heads are then crossed. Here, the conductor ends of the corresponding unconnected winding heads are arranged in a ring-shaped single layer. This specifically means that the conductor ends are all arranged on imaginary circumferences around the stator axis. Thus, multiple radial single layers exist. The conductor ends of the unconnected winding heads form a ring-shaped arrangement of radially stacked groups. Therefore, each radially stacked group has multiple conductor groups staggered in the radial direction, all of which are located at the same angular position around the stator axis. Here, for example, the two conductor ends of each stacked group should be connected to each other to form a mating pair, such that each stacked group has multiple separate mating pairs after connection.

[0006] Furthermore, in the case of forming mating pairs, electrical connections, particularly welding, are performed on the conductor ends of the corresponding unconnected winding heads. This produces the finished stator winding. In this step, each conductor end forms a mating pair with the adjacent conductor end in the radially stacked group of winding heads, wherein the mating pairs are arranged in annular mating layers. The number of mating layers corresponds to half that of a single layer. The mating layers are therefore arranged similarly to single layers, wherein two single layers are combined into a mating layer by electrically connecting the respective conductor ends. With a stator winding thus manufactured, current can flow through the stator in a meandering manner.

[0007] After welding, the conductor end of one of the mating layers is moved circumferentially relative to the conductor end of the adjacent mating layer. In particular, all the conductor ends of the mating layers are moved relative to the conductor ends of the adjacent mating layers in this manner. Torsional movement is particularly advantageous. This movement eliminates the undesirable weld connection between two adjacent mating layers in the finished winding head.

[0008] Movement along the circumferential direction occurs only within the elastic regions of the conductor elements. This prevents permanent deformation. More precisely, it ensures that no unwanted connections exist between the conductor elements. This circumferential movement also allows for automated implementation of the method without human intervention.

[0009] The dependent claims describe preferred improvements of the invention.

[0010] Preferably, two tool discs are inserted axially onto the conductor ends of the corresponding winding heads. The axial direction is particularly oriented along the central axis of the motor. The tool discs are moved relative to each other, particularly about the tool axis, to allow the conductor ends of two adjacent mating layers to move relative to each other, especially to twist. The tool discs, in particular, allow multiple conductor ends, preferably all mating layers, to move simultaneously. This eliminates the need for visual inspection; more precisely, the movement generated by the tool discs reliably eliminates all unwanted contact.

[0011] Furthermore, the present invention relates to a manufacturing apparatus for performing the methods described above. The manufacturing apparatus has at least one tool disk, each tool disk having a receiving opening for partially or completely receiving one radially stacked group. Thus, multiple or all radially stacked groups can be moved via the tool disk. Consequently, finishing for eliminating unwanted contacts becomes simple, because it is not necessary to process each mating pair individually, but rather that only the tool disk can be manipulated.

[0012] A particular advantage is that the receiving opening of the corresponding tool disc has an inlet ramp. The inlet ramp is used to guide the radially stacked assembly into the receiving opening along the axial direction. This allows the tool disc to be easily and reliably applied to the winding head. The risk of damage to the conductor ends by the tool disc is minimized.

[0013] Furthermore, it is preferably specified that the manufacturing apparatus comprises at least two tool disks. Of these tool disks, at least one tool disk is rotatably configured about a tool axis. The tool axis is particularly located on the stator axis. It is particularly advantageous that the two tool disks are configured to rotate relative to each other. Alternatively, one tool disk may be fixed and the other movable.

[0014] The receiving openings of the corresponding tool trays preferably have side edges for applying force-relieving forces along the circumferential direction to one or more conductors of the radially stacked group. The side edges enable the mating movement of the stacked group, thereby allowing undesirably connected adjacent mating pairs to be separated by means of appropriate relative movement.

[0015] In a particularly advantageous design, at least one side-edge protrusion is constructed along the side edge of at least one of the receiving openings. The side-edge protrusion is used to selectively load specific conductors or mating pairs within the radially stacked group. This also allows for reliable movement of multiple mating pairs within each stacked group, particularly enabling opposite movements.

[0016] Preferably, the receiving openings of the two tool disks are each configured to receive the entire radial stack and each has a closed edge. The tool disks are arranged in a stacked manner, particularly along the axial direction. The aforementioned side protrusions facilitate easy and reliable mating of the individual engagement movements of the stack.

[0017] In another design, the two tool disks are specified to include an internal gear ring and an external gear ring. The receiving openings of both tool disks are formed to be open in the radial direction and are designed to receive a portion of the stack assembly. Preferably, the receiving openings are used to receive only a portion of the stack assembly, particularly half, one-third, or two-thirds of the stack assembly.

[0018] The preferred tool tray is stationary, and each stack has a mechanism for moving adjacent mating parts relative to each other. Manipulation of the tool tray is thus simple and inexpensive. Attached Figure Description

[0019] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings. In the drawings: Figure 1 A schematic diagram of an electric motor manufactured according to an embodiment of the present invention is shown; Figure 2A schematic diagram of a manufacturing station according to an embodiment of the present invention is shown; Figure 3 A schematic spatial view is shown of the stator of an electric motor being machined at a manufacturing station according to a first alternative embodiment of the invention. Figure 4 A schematic cross-sectional view is shown of the stator of an electric motor being machined at a manufacturing station according to a first alternative embodiment of the invention. Figure 5 A schematic first detailed view is shown of a manufacturing station that processes the stator of an electric motor using a first alternative according to an embodiment of the invention; Figure 6 A schematic second detailed view is shown of the stator of the motor being machined at a manufacturing station according to a first alternative embodiment of the invention; Figure 7 A schematic third detailed view is shown of the stator of the motor being machined at a manufacturing station according to a first alternative embodiment of the invention; Figure 8 A first schematic diagram shows the processing of the stator of an electric motor using a manufacturing station according to a second alternative embodiment of the present invention; Figure 9 A schematic diagram of a tool tray in a manufacturing station according to a second alternative embodiment of the invention is shown; and Figure 10 A schematic diagram of the machining process for the stator of an electric motor is shown. Detailed Implementation

[0020] Preferably, all identical components, elements and / or units are given the same reference numerals in all figures.

[0021] Figure 1 An electric motor 1 manufactured according to an embodiment of the present invention is shown. The electric motor 1 has a stator 1a and a rotor 1b. The stator 1a has a stator body 2 and a stator winding, wherein the stator winding is formed by a plurality of electrically connected conductor elements 4. The stator winding forms winding heads 4a on the end sides 2a of the stator body 2.

[0022] The stator 1a has a stator axis 100 as its central axis, which is also the rotation axis of the rotor 1b. An axial direction 300 is defined along the stator axis 100, and a radial direction 400 is defined perpendicular to the stator axis. Furthermore, a circumferential direction 200 is defined around the stator 1b and thus around the stator body 2.

[0023] The manufacture of motor 1 is performed using a manufacturing apparatus 9 according to an embodiment of the present invention, which is particularly configured to perform the method described according to an embodiment of the present invention. The manufacturing apparatus 9 is exemplarily... Figure 2 The diagram shows, schematically illustrating only welding station 9a and finishing station 9b.

[0024] According to one embodiment, a method for manufacturing an electric motor 1 first includes the steps of providing or manufacturing a stator body 2 having stator slots 3 and inserting conductor elements 4 into the stator slots 3 while forming unconnected winding heads 4a on at least one end side 2a of the stator body 2. The stator body 2 is provided or manufactured, in particular, as a stator lamination assembly.

[0025] The following uses Figures 3 to 7 To describe the method used to manufacture motor 1. Figure 3 A schematic diagram of the stator body 2 is shown. Figure 4 A schematic cross-sectional view of the stator body 2 is shown. Figure 5 , 6 Figures 7 and 8 schematically show a detailed view of the winding head 4a.

[0026] Subsequently, the conductor ends 4b of the corresponding unconnected winding heads 4a are crossed. For this purpose, the conductor ends 4b are arranged such that the conductor ends 4b of the corresponding unconnected winding heads 4a are arranged in annular single layers 10a, 10b, 10c, 10d, 10e, and 10f. Here, the conductor ends 4b of the unconnected winding heads 4a form an annular arrangement of radially stacked groups 5. The stacked groups 5 thus have conductor ends 4b staggered along the radial direction 400, all of which are arranged at correspondingly identical angular positions about the stator axis 100.

[0027] To manufacture the finished stator winding, the conductor ends 4b of the corresponding unconnected winding heads 4a are electrically connected, forming engagement pairs 6 that engage with each other. The electrical connection is performed, for example, by welding, particularly laser welding. In the illustrated embodiment, two conductor ends 4b are connected to form engagement pairs 6. In the radial stacking group 5 of the winding heads 4a, each conductor end 4b forms an engagement pair 6 with its adjacent conductor end 4b. The engagement pairs 6 are arranged in annular engagement pairs 11a, 11b, 11c, wherein the number of engagement pairs 11a, 11b, 11c corresponds to half that of the single layers 10a, 10b, 10c, 10d, 10e, 10f. Thus, in particular, each pair of single layers 10a, 10b, 10c, 10d, 10e, 10f forms engagement pairs 11a, 11b, 11c. The electrical connection is performed, for example, in the welding station 9a of the manufacturing apparatus 9 by means of a laser welding device 15.

[0028] After welding, the conductor end 4b of one of the mating layers 11a, 11b, 11c is moved circumferentially 200° relative to the conductor end 4b of the adjacent mating layers 11a, 11b, 11c. This is done, for example, in the finishing station 9b of the manufacturing apparatus. It is particularly advantageous that, after welding, all the conductor ends 4b of the mating layers 11a, 11b, 11c are moved circumferentially 200° relative to the adjacent mating layers 11a, 11b, 11c. This movement is used to eliminate unwanted welded connections between two adjacent mating layers 11a, 11b, 11c in the finished winding head 4a. In this way, it can be ensured that electrical connections exist only within the mating layers 11a, 11b, 11c, but not beyond the mating layers 11a, 11b, 11c of the stack group 5. If a weld connection is unintentionally created in the preceding welding steps that extends beyond the mating layers 11a, 11b, 11c of the stack group 5, it is eliminated by the relative movement of the conductor ends 4b. The movement of the conductor ends is in particular a torsion about the stator axis 100.

[0029] To enable movement of the conductor end 4b, the manufacturing apparatus 9 advantageously includes at least one tool disk 7, 8. Particularly advantageously, two tool disks 7, 8 are provided. Each tool disk 7, 8 has receiving openings 7a, 8a for partially or completely receiving one radial stack group 5. If two tool disks 7, 8 are present, then at least one of the tool disks is rotatably configured about a tool axis. In an advantageous design, the tool disks 7, 8 are capable of rotating in opposite directions about the tool axis. Here, the stator body 2 is positioned in the manufacturing apparatus 9 such that the tool axis advantageously corresponds to the stator axis 100.

[0030] The movement of the conductor end 4b is preferably within the elastic limit of the conductor element 4. This avoids permanent plastic deformation of the conductor element 4. Therefore, the conductor end 4b is not moved or bent; more precisely, the conductor end 4b remains in the position determined by the intersection. Thus, the movement only eliminates unwanted connections.

[0031] The aforementioned movement steps of the conductor ends 4b are carried out using two tool disks 7 and 8, thereby inserting the tool disks 7 and 8 into the conductor ends 4b of the corresponding winding heads 4a along the axial direction 300. Thus, the conductor ends 4b are particularly embedded into the receiving openings 7a and 8a. Through the opposing movement or twisting of the tool disks 7 and 8, the conductor ends 4b of the two adjacent mating layers 11a, 11b, and 11c are moved or twisted relative to each other. Thus, the movement of the conductor ends 4b of all mating layers 11a, 11b, and 11c can be performed in a simple manner and method. This achieves the reliable elimination of all unwanted connections between the mating layers 11a, 11b, and 11c. Manual finishing can thus be eliminated or at least reduced.

[0032] Especially Figure 6 and 7 As shown, the receiving openings 7a and 8a of the corresponding tool trays 7 and 8 have guide ramps 12. The guide ramps 12 facilitate the insertion of the tool trays 7 and 8 along the axial direction 300. The guide ramps 12 are thus used to insert the radially stacked assembly 5 along the axial direction 300 into the receiving openings 7a and 8a.

[0033] In this embodiment, such as Figures 3 to 7 In the first alternative shown, the two tool disks 7 and 8 include an internal gear ring 8 and an external gear ring 7. The receiving openings 7a and 8a of the two tool disks 7 and 8 are formed openly along the radial direction 400° and are designed to receive a portion of the stack assembly 5. Figures 3 to 7 As shown, each receiving opening 7a, 8a is configured to receive half of the stack group 5, but only to move one-third of the stack group.

[0034] The receiving openings 7a and 8a of the corresponding tool disks 7 and 8 each have a side edge 13 for loading one or more conductors 4a of the radially stacked group 5 along the circumferential direction 200 to relieve force. A side edge protrusion 14 is constructed along each side edge 13 of the receiving openings 7a and 8a for selectively loading a specific conductor or mating pair 6 of the radially stacked group 5. In a first alternative, a force in the circumferential direction is applied to the conductor end 5 of the mating layer 11c outside the radial direction 400 via the side edge protrusion 14 of the side edge 13 of the first receiving opening of the outer gear ring 7. The side edge protrusion 14 of the side edge 13 of the first receiving opening of the outer gear ring 7 can be placed on the conductor end 4b of the outer mating layer 11c. A force in the circumferential direction is applied to the conductor end 5 of the mating layer 11a inside the radial direction 400 via the side edge protrusion 14 of the side edge 13 of the second receiving opening of the inner gear ring 8. The side edge protrusion 14 of the side edge 13 of the second receiving opening 8a of the internal gear ring 8 can be placed on the conductor end 4b of the inner mating layer 11a. Through the relative movement of the tool discs 7 and 8 along the circumferential direction 200 caused, for example, by the counterclockwise movement of the internal gear ring 8 and the clockwise movement of the external gear ring 7, a dissolving force is applied on the one hand between the mating of the inner mating layer 11a and the middle mating layer 11b, and on the other hand, a dissolving force is applied between the mating of the middle mating layer 11b and the outer mating layer 11c. Thus, all unwanted connections between the respective mating layers 11a, 11b, and 11c are completely eliminated.

[0035] In the second alternative of this embodiment, tool disks 7 and 8 are as follows: Figure 8 , 9 As shown in Figure 10, they are stacked along the axial direction 300. Here, the receiving openings 7a and 8a of the two tool disks 7 and 8 are each configured to receive a complete radial stack group 5. The receiving openings 7a and 8a also have closed edges. Thus, each stack group 5 is preferably surrounded not only by the first tool disk 7 but also by the second tool disk 8.

[0036] To allow selective movement of the mating pairs 6, the side edges 13 of the receiving openings 7a and 8a each have a side edge protrusion 14. The first tool disk 7 has a side edge protrusion 14 for placing the mating pairs 6 on the mating layer 11b therein, while the side edge 13 of the second receiving opening 8a of the second tool disk 8 has a side edge protrusion 14 for placing the mating pairs 6 on the outer mating layer 11a and the inner mating layer 11c. If the tool disks 7 are moved relative to each other, this relative movement is transmitted to the conductor ends 4b of the respective mating layers 11a, 11b, and 11c via the side edge protrusions 14. This results in the application of a disintegrating force along the circumferential direction 200 to the conductor ends 4b of the respective adjacent mating pairs 6, thereby eliminating the connection between these mating pairs 6. This destroys unwanted electrical connections.

[0037] In another alternative embodiment, stationary tool trays 7 and 8 are provided. Tool trays 7 and 8 have mechanisms for moving adjacent engaging pairs 6 of the stack group 5 relative to each other.

Claims

1. A method for manufacturing an electric motor (1), comprising the following steps: a. To provide or manufacture stator bodies (2) having stator slots (3), especially stator laminations; b. With an unconnected winding head (4a) formed on at least one end side (2a) of the stator body (2), insert the conductor element (4) into the stator slot (3); c. The conductor ends (4b) of the corresponding unconnected winding heads (4a) are crossed, wherein the conductor ends (4b) of the corresponding unconnected winding heads (4a) are arranged in particular in an annular single layer (10a, 10b, 10c, 10d, 10e, 10f), and wherein the conductor ends (4b) of the unconnected winding heads (4a) form an annular arrangement of radially stacked groups (5); and d. In the case of forming engagement pairs (6) that engage with each other, the conductor ends (4b) of the corresponding unconnected winding heads (4a) are electrically connected, in particular welded, to manufacture a finished stator winding, wherein each conductor end (4b) in the radial stacked group (5) of the winding heads (4a) forms an engagement pair (6) with the adjacent conductor end (4b), wherein the engagement pairs (6) are arranged in annular engagement pair layers (11a, 11b, 11c), wherein the number of engagement pair layers (11a, 11b, 11c) corresponds to half of the number of single layers (10a, 10b, 10c, 10d, 10e, 10f). Its features are, The conductor end (4b) of one, in particular all, of the mating layers (11a, 11b, 11c) is moved, in particular twisted, relative to the conductor end (4b) of the adjacent mating layers (11a, 11b, 11c) in the circumferential direction (200) after welding, so as to eliminate the undesirable weld connection between two adjacent mating layers (11a, 11b, 11c) in the winding head (4a) of the finished product.

2. The method according to claim 1, characterized in that, Two tool disks (7, 8) are inserted along the axial direction (300) onto the conductor ends (4b) of the corresponding winding heads (4a), wherein the tool disks (7, 8) are moved relative to each other, especially twisted, so that the conductor ends (4b) of the two adjacent mating layers (11a, 11b, 11c) move relative to each other, especially twisted.

3. A manufacturing apparatus (9) for performing the method according to any one of the preceding claims, wherein the manufacturing apparatus (9) comprises at least one tool disk (7, 8), each tool disk having a receiving opening (7a, 8a) for partially or completely receiving each of a radially stacked group (5).

4. The manufacturing apparatus (9) according to claim 3, characterized in that, The receiving openings (7a, 8a) of the corresponding tool disks (7, 8) have an inlet ramp (12) for inserting radial stacks (5) into the receiving openings (7a, 8a) along the axial direction (300).

5. The manufacturing apparatus (9) according to claim 3 or 4, characterized in that, The manufacturing apparatus (9) includes at least two tool disks (7, 8), at least one of which is rotatably configured about a tool axis.

6. The manufacturing apparatus (9) according to any one of claims 3 to 5, characterized in that, The receiving openings (7a, 8a) of the corresponding tool disks (7, 8) each have a side edge (13) for loading one or more conductors (4a) of the radial stack group (5) with a force-relieving force along the circumferential direction (200).

7. The manufacturing apparatus (9) according to claim 6, characterized in that, At least one side protrusion (14) is constructed along the side edge (13) of at least one of the receiving openings (7a, 8a) to selectively load a particular conductor (4) or engagement pair (6) of the radial stack (5).

8. The manufacturing apparatus (9) according to any one of claims 3 to 7, characterized in that, The receiving openings (7a, 8a) of the two tool disks (7, 8) are respectively configured to receive the entire radial stack group (5) and each has a closed edge.

9. The manufacturing apparatus (9) according to any one of claims 3 to 8, characterized in that, The two tool disks (7, 8) include an internal gear ring (8) and an external gear ring (7), wherein the receiving openings (7a, 8a) of the two tool disks (7, 8) are formed openly in the radial direction (400) and are made for receiving a portion, especially half, one-third or two-thirds, of the stacked assembly (5).

10. The manufacturing apparatus (9) according to any one of claims 5 to 9, characterized in that, The tool disks (7, 8) are stationary and each stack group (5) has a mechanism for moving the mating pairs (6) of the stack groups (5) relative to each other.

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