Twisting Device and Method for a Hairpin Winding

Abstract

A device for twisting hairpin ends of a coil formed from hairpins for an electric machine includes: a plurality of coaxially arranged twisting rings having: two outer twisting rings and, therebetween, at least at least two inner twisting rings. The twisting rings have, in each instance, at an axial end facing hairpin ends, a plurality of pockets distributed over a circumference for receiving a hairpin end, respectively. The twisting rings are twistable in opposite directions relative to one another, the twisting rings having couplings by which twisting rings with like rotational direction are connectable.

Claims

1-14. (canceled)

15. A device (1) for twisting hairpin ends of a coil formed from hairpins for an electric machine, the device comprising: a plurality of coaxially arranged twisting rings (2.1; 2.2; 3) comprising: two outer twisting rings (2.1; 2.2) and, therebetween, at least at least two inner twisting rings (3), wherein the twisting rings (2.1; 2.2; 3) have, in each instance, at an axial end facing hairpin ends, a plurality of pockets (6; 6.1; 6.2) distributed over a circumference for receiving a hairpin end, respectively, and wherein the twisting rings (2.1; 2.2; 3) are twistable in opposite directions relative to one another, wherein the twisting rings (2.1; 2.2; 3) have couplings (4.1; 4.2) by which twisting rings (2.1; 2.2; 3) with like rotational direction are connectable.

16. The device (1) according to claim 15, wherein directly adjacent twisting rings (2.1; 2.2; 3) are twistable in opposite directions.

17. The device (1) according to claim 16, wherein at least the inner twisting rings (3) have a passage (5.1; 5.2) for the couplings (4.1; 4.2) of the twisting rings (2.1; 2.2; 3) with a different rotational direction.

18. The device (1) according to claim 17, wherein the passage (5.1; 5.2) is configured as an elongated hole extending over a portion of the circumference.

19. The device (1) according to claim 15, wherein the twisting rings (2.1; 2.2; 3) have in each instance at least two couplings (4.1; 4.2) which are distributed, preferably symmetrically, over the circumference.

20. The device (1) according to claim 15, wherein the couplings (4.1; 4.2) are each configured as an alignment pin receivable in corresponding receptacles at the twisting rings (2.1; 2.2; 3).

21. The device (1) according to claim 20, wherein at least one of the twisting rings (2.1; 2.2; 3) have receptacles which, in a movement direction, have a clearance relative to the alignment pin in the initial position in order to move the twisting ring (2.1; 2.2; 3) by a rotational angle that is smaller than the alignment pin by an amount corresponding to the clearance.

22. The device (1) according to claim 15, wherein the quantity of twisting rings (2.1; 2.2; 3) corresponds to the quantity of layers of the coil.

23. The device (1) according to claim 15, wherein the quantity of pockets (6; 6.1; 6.2) per twisting ring (2.1; 2.2; 3) corresponds to the quantity of slots of the coil.

24. The device (1) according to claim 15, wherein the pockets (6; 6.1; 6.2) are configured to be open on one side in radial direction, wherein the pockets (6; 6.1; 6.2) of the outer twisting rings (2.1; 2.2) are configured in each instance to open in direction of the further twisting rings (2.1; 2.2; 3), and in that the pockets (6; 6.1; 6.2) of the inner twisting rings (3) are configured in each instance to open toward the open side of the pockets (6; 6.1; 6.2) of a directly adjacent twisting ring (2.1; 2.2; 3).

25. The device (1) according to claim 15, wherein the pockets (6; 6.1; 6.2) have at least a depth in axial direction corresponding to an uninsulated length of the hairpin ends.

26. The device (1) according to claim 15, wherein the outer twisting rings (2.1; 2.2) have fasteners (7) by which the device (1) is connectable to drives (8) for the rotational movements.

27. A method for twisting hairpin ends of a coil for an electric machine by the device (1) according to claim 15, the method comprising: fitting the device (1) on the hairpin ends, wherein at least the uninsulated hairpin ends are received in pockets (6; 6.1; 6.2) of the twisting rings (2.1; 2.2; 3); rotating the twisting rings (2.1; 2.2; 3) in opposite directions, wherein twisting rings (2.1; 2.2; 3) which are connected to one another via couplings (4.2; 4.2) are rotated in the same direction; and removing the coil with shaped hairpin ends from the device (1).

28. An electric machine with a coil which is formed from hairpins and which is produced by the method according to claim 27.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The invention will be explained in more detail in the following with reference to the figures. Like or similar component parts are designated by consistent reference numerals.

[0032] In the figures:

[0033] FIG. 1 is an exemplary embodiment of a device;

[0034] FIG. 2 is a further exemplary embodiment of a device;

[0035] FIG. 3 is a section in radial direction of an exemplary embodiment according to FIG. 2;

[0036] and

[0037] FIG. 4 is a portion of a further exemplary embodiment of a device in axial section.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0038] FIG. 1 shows an exemplary embodiment of a device 1. The device 1 comprises a plurality of twisting rings 2.1; 2.2; 3 which are coaxially arranged. Accordingly, a plurality of inner twisting rings 3 is located between the two outer twisting rings 2.1; 2.2. The outer twisting rings 2.1; 2.2 can be constructed more solidly. The radially inner outer twisting ring 2.2 can also be formed as a solid cylinder. The outer twisting rings 2.1; 2.2 are connected in each instance to a separate drive 8 via fasteners 7 in order to move the twisting rings 2.1; 2.2 opposite one another in circumferential direction. Only one carrier plate is shown in FIG. 1 for a drive 8 and is connected to the radially outer outer twisting ring 2.1.

[0039] The twisting rings 2.1; 2.2; 3 with like rotational direction are connected to one another in each instance via couplings 4; 4.1; 4.2. A drive force is transmitted from a driven twisting ring 2.1; 2.2; 3, preferably an outer twisting ring 2.1; 2.2, to the further twisting rings 2.1; 2.2; 3, preferably inner twisting rings 3, with like rotational direction by means of the couplings 4; 4.1; 4.2.

[0040] In order to prevent the couplings 4; 4.1; 4.2 from being blocked by twisting rings 2.1; 2.2; 3 located between or adjacent to the connected twisting rings 2.1; 2.2; 3, these twisting rings 2.1; 2.2; 3 have, in each instance, passages 5; 5.1; 5.2 for the couplings 4; 4.1; 4.2 of the other respective rotational direction. In FIG. 1, passages 5; 5.2 are also provided in the radially outer outer twisting ring 2.1. These passages 5; 5.1; 5.2 facilitate the guidance of the couplings 4; 4.1; 4.2, particularly in axial direction, and provide a better transmission of force to the adjacent twisting ring 3 connected to couplings 4; 4.1; 4.2. Correspondingly, passages 5; 5.1 can also be similarly provided at the radially inner outer twisting ring 2.2. Instead of continuous cutouts in the outer twisting rings 2.1; 2.2, the passages 5; 5.1; 5.2 can also be formed by slots. Embodiment forms are also possible in which no passages 5; 5.1; 5.2 are provided in the outer twisting rings 2.1; 2.2, which lowers production expenditure.

[0041] In embodiment forms, the couplings 4; 4.1; 4.2 can also be connected to the respective drive instead of the twisting rings 2.1; 2.2; 3. This is particularly advantageous in embodiment forms in which the outer twisting rings 2.1; 2.2 have a like rotational direction.

[0042] Pockets 6; 6.1; 6.2 which serve to receive hairpin ends of a coil which is held at least in circumferential direction are provided in each instance at an axial end of the individual twisting rings 2.1; 2.2; 3. The hairpin ends are moved in circumferential direction and accordingly shaped when the twisting rings 2.1; 2.2; 3 are twisted. The coil is preferably merely guided in axial direction so that a change in the axial length due to the deformation of the hairpin ends in circumferential direction can be compensated or adjusted.

[0043] FIG. 1 additionally shows optional positioning indicators 9 with which, for example, an initial position of the device can be marked. The positioning indicators 9 are provided as radial markings on two adjacent twisting rings 2.1; 2.2; 3. Accordingly, a correct positioning or orientation of the device 1, more precisely of the twisting rings 2.1; 2.2; 3, relative to one another can be checked and ensured.

[0044] Embodiment forms are also possible in which the outer twisting rings 2.1; 2.2 have no pockets 6; 6.1; 6.2 or have pockets 6; 6.1; 6.2 which are not utilized and the outer twisting rings 2.1; 2.2 are connected to the drives and only actuate the couplings 4 and hold the inner twisting rings 3. In this way, the same outer twisting rings 2.1; 2.2 can be used for different implementations with different inner twisting rings 3 in order to lower tool costs for each implementation.

[0045] FIG. 2 shows a further embodiment form of a device 1. The basic construction substantially corresponds to that of the construction described above referring to FIG. 1, and reference is made to this figure.

[0046] One difference compared to the exemplary embodiment in FIG. 1 consists in that the outside outer twisting ring 2.1 and the inner twisting rings 3 lie on a portion of the inside outer twisting ring 2.2 extending radially on the side remote of the pockets 6. This has the advantage, among others, that the device 1 can be prepared or provided separately and can be handled and installed in the machine as a unit.

[0047] Retainers 11 which prevent the outer twisting rings 2.1; 2.2 from lifting relative to one another in particular, but which allow a relative movement in circumferential direction, are preferably provided. Retainers 11 which engage in an extension of the passages 5, are provided in the depicted exemplary embodiment.

[0048] A plurality of notches provided at the outer lateral surfaces of the outer twisting rings 2.1; 2.2 are incorporated as positioning indicators 9 in FIG. 2. Different positions can be marked by a plurality of positioning indicators 9 provided at a defined distance from one another and, aside from an initial position, for example, different twisting angles can also be determined for different variants of coils.

[0049] FIG. 3 shows a sectional view of an exemplary embodiment according to FIG. 2, in which the section extends along a plane in the area of the passages 5 which runs perpendicular to the rotational axis.

[0050] The outer twisting rings 2.1; 2.2 are solidly constructed. The inside outer twisting ring 2.2 is connected to a drive by fasteners 7, in this case screws. Further, the outer twisting ring 2.2 on the inner side has an area which extends outward in radial direction and at which retainers 11 are provided. The retainers 11 are formed in this exemplary embodiment as washers which are flattened on one side and which, depending on the rotational position, allow a lifting of the outside outer twisting ring 2.1 or engage in a groove of the outer twisting ring 2.1 formed as an extension of the passage 5; 5.2 in order to prevent lifting. The groove can be connected to the passage 5; 5.2 or can also be formed separate therefrom. Also, the groove can have a width and/or depth deviating from that of the passage 5; 5.2 and/or can be provided at another height in axial direction. It is also possible that the groove is formed by the passage 5; 5.2 itself, especially when the passage 5; 5.2 encompasses a circumferential area that is larger than the twisting angle or the couplings 4.2 arranged in the passage 5; 5.2 do not extend over the entire radial length of the outer twisting ring 2.1.

[0051] Couplings 4.1; 4.2 are received, respectively, in the outer twisting rings 2.1; 2.2 in order to connect twisting rings 2.1; 2.2; 3 of like rotational direction to one another. Corresponding passages 5.1; 5.2 for the couplings 4.1; 4.2 of the other respective rotational direction are correspondingly provided in the twisting rings 2.1; 2.2; 3. The twisting rings 2.1; 2.2; 3 can be twisted relative to the traversing couplings 4.1; 4.2 through the passages 5.1; 5.2.

[0052] In the depicted exemplary embodiment, the couplings 4.1; 4.2 are constructed as alignment pins extending in radial direction. A threaded bore hole is provided at one end in the alignment pins in order to make possible or simplify disassembly of the device.

[0053] Three couplings 4.1; 4.2 are arranged for each rotational direction is FIG. 3 so as to be uniformly distributed over the circumference. More couplings 4.1; 4.2 or fewer couplings 4.1; 4.2 can also be provided for each rotational direction depending on the size of the device and the occurring forces. Different quantities of couplings 4.1; 4.2 can also be provided for the different rotational directions.

[0054] Couplings 4.1 for a first rotational direction are received in the outside outer twisting ring 2.1 for a first rotational direction. These couplings 4.1 are also connected to every second inner twisting ring 3 so that the latter can be moved in a like rotational direction by a like twisting angle. In the inner twisting rings 3 located therebetween and in the inside outer twisting ring 2.2, corresponding passages 5.1 are provided through which the couplings 4.1 for a first rotational direction can pass and accordingly be moved relative to one another.

[0055] Correspondingly, couplings 4.2 for a second rotational direction are received in the inside outer twisting ring 2.2. These couplings 4.2 connect the inside outer twisting ring 2.2 to the corresponding inner twisting rings 3 with like rotational direction. Similarly, the twisting rings 2.1; 3 with a first rotational direction have corresponding passages 5.2 for the couplings 4.2 of the second rotational direction.

[0056] FIG. 4 shows a section along a plane of a further exemplary embodiment extending in radial and axial direction, only one half of which is shown. The twisting rings 2.1; 2.2; 3 are shown in an initial position.

[0057] In this exemplary embodiment, four inner twisting rings 3 are provided in addition to the outer twisting rings 2.1; 2.2 and, just as in the other exemplary embodiments, a different quantity of twisting rings may be provided depending on the coil to be produced.

[0058] Pockets 6; 6.1; 6.2 for receiving contact ends which are to be shaped are formed in each instance at an axial end of the twisting ring 2.1; 2.2; 3. It is shown that the pockets 6; 6.1; 6.2 in this exemplary embodiment are open in each instance toward a circumferential surface of the twisting rings 2.1; 2.2; 3, and the open circumferential surfaces of directly adjacent twisting rings 2.1; 2.2; 3 face one another in each instance. As a result, the closed circumferential surfaces of the inner twisting rings 3 face a closed circumferential surface of a directly adjacent inner twisting ring 3 in each instance. By means of a configuration of this kind, besides the twisting movement in which they are shaped in circumferential direction, the contact ends can approach one another simultaneously as contact pairs to be connected to one another in a double layer.

[0059] With the individual pockets 6; 6.1; 6.2 of a twisting ring 2.1; 2.2; 3, particularly of an inner twisting ring 3, the open circumferential surface and closed circumferential surface can be exchanged varyingly in order to provide contact pairs for a transition between the double layers. Correspondingly, pockets 6.1 for contact ends which are to be connected to an interconnect and therefore not connected to another contact end can be formed without an open circumferential surface or can oppose a closed circumferential surface at the end of the twisting movement.

[0060] Particularly the outer twisting rings 2.1; 2.2 can have a quantity of pockets 6; 6.1; 6.2 diverging from the quantity of slots of the coil to be produced, especially in embodiment forms in which more twisting rings are provided in total than layers at the coil.

[0061] The inner twisting rings 3 in the pockets 6.2 shown in FIG. 4 have a second depth in axial direction so that at least the—preferably uninsulated—contact ends which are to be deformed and subsequently connected to form contact pairs can be securely received, and an end region of the contact ends which extends in axial direction after deformation is also retained by means of this second axial depth.

[0062] Conversely, the outer twisting rings 2.1; 2.2 shown in FIG. 4 have pockets 6.1 which have a first axial depth with a greater extension in axial direction than the pockets 6.2 with a second depth of the inner twisting rings 3. The latter are provided for receiving contact ends which are connected to an interconnect and are not combined to form a contact pair. The larger axial extension of the first axial depth provides room for the contact ends for the interconnect which are generally formed to be longer.

[0063] Pockets 6; 6.1; 6.2 with a first axial depth and/or second axial depth can be provided at a twisting ring 2.1; 2.2; 3. The pockets 6.1 with a first axial depth are provided at least at the positions for contact ends which are to be connected to an interconnect. In order to enable the use of like twisting rings 2.1; 2.2; 3 for different coils if required and/or to simplify production and assembly, all of the pockets 6 of a twisting ring 2.1; 2.2; 3 can also be provided with pockets 6.1 of a first axial depth, since individual contact ends which are to be connected to form a contact pair can also be held by the latter for deformation.

[0064] The inner twisting rings 3 of the exemplary embodiment shown in FIG. 4 have coaxially nested projections in radial direction on their axial side remote of the pockets 6; 6.1; 6.2 in order to augment the width of this end face in radial direction.

[0065] The couplings 4.1; 4.2 are connected to the outer twisting rings 2.1; 2.2 and encompass a portion extending in axial direction, there being provided a sufficient clearance between the couplings 4.1; 4.2 for receiving the nested projections of the inner twisting rings 3 in radial direction.

[0066] Adjoining the axial portion of the couplings 4.1; 4.2 in each instance are radially extending portions which overlap at least the radial projections of the inner twisting rings 3 with a like rotational direction. As is shown, the radial portions of the couplings 4.1; 4.2 can be successive along axial direction. In a construction of this kind, at least the couplings 4.1; 4.2 facing the inner twisting rings 3, namely, in FIG. 4, couplings 4.2 for a second rotational direction, have passages 5.1; 5.2 for the couplings 4.1; 4.2 on the side facing away.

[0067] The connection between the couplings 4.1; 4.2 and the inner twisting rings 3 is carried out in the depicted exemplary embodiment via connection pins 10. In FIG. 4, the connection pins 10 of the couplings 4.1 for a first rotational direction extend through passages 5.1 in couplings 4.2 for a second rotational direction. Instead of connection pins 10, alignment pins or the like can also be used. Details of the passages 5.1 with respect to circumferential length and the like are analogous to those given for the other exemplary embodiments.

[0068] Alternatively, the radially extending portions of the couplings 4.1; 4.2 can extend in a plane when they extend only over partial areas of the circumference and have a sufficient clearance in circumferential direction for the twisting movement. In variants of this kind, a passage 5.1; 5.2 can be omitted and the couplings 4.1; 4.2 can be used directly as a stop for limiting the twisting angle.

[0069] The invention is not limited to the described embodiments. As stated above, only individual advantageous features may be provided, or various features of different examples may be combined with one another.

[0070] Although exemplary embodiments have been discussed in the above description, it should be noted that numerous modifications are possible. Furthermore, it should be noted that the exemplary embodiments are merely examples which are not intended to limit the scope of protection, the applications and the structure in any way. Rather, a person skilled in the art will take from the above description a guideline for implementation of at least one exemplary embodiment, wherein various modifications may be made, in particular with regard to the function and arrangement of the described components, without departing from the scope of protection as can be gathered from the claims and equivalent feature combinations.