APPARATUS FOR RESHAPING A CONDUCTOR PIECE ARRANGED IN A STATOR CORE AND A CORRESPONDING METHOD

Abstract

The invention relates to an apparatus and a method for reshaping one or more conductor pieces arranged in a stator core, wherein a plurality of conductor pieces is arranged in the stator core, the conductor pieces being arranged on a plurality of circular paths running in a circumferential direction in rows which extend in a radial direction, and wherein the reshaping takes place in a free end of the conductor piece projecting out of the stator core.

Claims

1. Apparatus for reshaping one or more conductor pieces arranged in a stator core, wherein a plurality of conductor pieces is arranged in the stator core, and is arranged on a plurality of circular paths running in a circumferential direction in rows which extend along a radial direction, wherein the reshaping takes place in a free end of the conductor piece projecting out of the stator core, wherein the apparatus comprises: a receptacle for the stator core in a provided machining position in which the conductor pieces to be reshaped are arranged in an initial configuration before reshaping such that the conductor pieces projecting from the stator core project extended along a longitudinal direction out of the stator core; at least one bending unit for reshaping the conductor piece or pieces, wherein the bending unit in turn comprises: a positioning unit for positioning the bending unit relative to the receptacle for the stator core a contact portion which is configured to laterally contact the one or more conductor pieces to be reshaped; an actuator which is arranged and configured to move the contact portion relative to the positioning unit in order to reshape the conductor piece or pieces; characterized in that the contact portion is mounted in the positioning unit in such a way that when the actuator is actuated, the contact portion is moved in a first movement step relative to the positioning unit in a first bending direction, without changing its pivot positioning and in a second movement step, the movement of the contact portion in the first bending direction is superimposed with a pivoting movement.

2. Apparatus according to claim 1, characterized in that the contact portion is configured like a sleeve wherein the contact portion has a rounded edge for engagement between two conductor pieces arranged adjacent to one another and/or wherein the contact portion has a clamping device for clamping the conductor pieces accommodated between a clamping surface and a contact wall, and/or wherein the contact portion has a clamping device with a clamping element which is braced in the direction of a contact wall and has an inclined insertion surface.

3. Apparatus according to claim 1, characterized in that the bending unit comprises a first guide element and a second guide element, wherein the first guide element is pivotably mounted in the second guide element, and being spring-biased, and being coupled to the contact portion in such a way that a pivoting movement of the first guide element is transmitted to the contact portion, and wherein the second guide element is movable in a translatory manner relative to the positioning unit along the first bending direction.

4. Apparatus according to claim 1, characterized in that the positioning unit comprises a U-shaped frame element and in that the first guide element and the second guide element are mounted in the frame element.

5. Apparatus according to claim 4, characterized in that the frame element comprises a first stop lying in the first bending direction, which stop is arranged and configured for contacting the first guide element when said element is moved in the first bending direction, wherein the pivot point, in which the first guide element is connected to the second guide element, is arranged between the first stop and the contact portion.

6. Apparatus according to claim 4, characterized in that the frame element comprises a second stop lying in the first bending direction, which stop is arranged and configured for contacting the second guide element when said element is moved in the first bending direction and its movement in the first bending direction is limited.

7. Apparatus according to claim 3, characterized in that the second guide element comprises a fourth stop which limits the pivot positioning of the first guide element with respect to the second guide element in the first bending direction.

8. Apparatus according to claim 3, characterized in that the second guide element comprises a fifth stop, which limits the pivot positioning of the first guide element with respect to the second guide element counter to the first bending direction.

9. Apparatus according to claim 5, characterized in that the position of the first stop is adjustable.

10. Apparatus according to claim 3, characterized in that the contact portion is mounted in the first guide element so that it can be guided in a translatory manner by means of a pretensioned piston rod.

11. Apparatus according to claim 1, characterized in that the actuator has a joint.

12. Apparatus according to claim 1, characterized in that the apparatus comprises a counter-bearing device which is movably arranged in such a way that a counter-bearing portion can be placed against the conductor piece in order to define a first bending point.

13. Apparatus according to claim 4, characterized in that the counter-bearing device, the frame element and/or the actuator are arranged essentially in one plane.

14. Apparatus according to claim 12, characterized in that the counter-bearing portion can be placed against the conductor piece by a movement of the counter-bearing device in the second bending direction.

15. Apparatus according to claim 12, characterized in that the counter-bearing portion is arranged in such a way that it can be placed against the conductor piece in a region thereof directly adjacent to the stator core.

16. Apparatus according to claim 12, characterized in that the counter-bearing portion has at least in part a rounded shape.

17. Method for reshaping one or more conductor piece(s) arranged in a stator core, wherein a plurality of conductor pieces is arranged in the stator core, said conductor pieces being arranged on a plurality of circular paths running in a circumferential direction in rows which extend in a radial direction, wherein the reshaping takes place in a free end of the conductor piece projecting out of the stator core, wherein the procedure comprises: arranging the stator core in a provided machining position in which the conductor pieces to be reshaped are arranged in an initial configuration (before reshaping) such that the free ends of the conductor pieces projecting out of the stator core project extended along a longitudinal direction out of the stator core; moving a contact portion, which is configured to laterally contact the conductor piece to be reshaped or the conductor pieces to be reshaped, along the longitudinal direction into a contact position with the conductor piece or the conductor pieces in which the conductor piece or the conductor pieces are accommodated in the contact portion and contacted thereby at least laterally; moving the contact portion in a first bending direction, wherein an orientation of the contact portion remains unchanged, so that the conductor piece or conductor pieces accommodated in the contact portion is/are bent around a first bending point in the first bending direction and an end portion of the conductor piece or conductor pieces extending from the free end in the longitudinal direction remains in its orientation, and a second bending point, which is spaced apart from the first bending point, is defined by an edge of the contact portion, so that the conductor piece or conductor pieces accommodated in the contact portion is/are bent around the second bending point in a second bending direction; pivoting of the contact portion (26) such that the free end of the conductor piece or the free ends of the conductor pieces is/are bent in relation to the further course of the conductor piece or the conductor pieces around the second bending point in the second bending direction.

18. Method according to claim 17, characterized in that during the entire bending process the conductor piece or the conductor pieces is/are contacted from the side as well as from its free end by the contact portion and the change in the position of the free end in the longitudinal direction is compensated by a movement of the contact portion in order to maintain contact with the free end.

19. Method according to claim 17, characterized in that, while the contact portion is being pivoted, the second bending point is moved relative to the stator core.

20. Method according to claim 17, characterized in that the bend around the first bending point and the bend around the second bending point run in one plane.

21. Method according to claim 17, characterized in that the bending at the first bending point and/or at the second bending point is by a greater angle than that provided for in the final desired shape, so that springback of the conductor piece or conductor pieces is/are at least partially compensated.

22. Method according to claim 17, characterized in that an apparatus is used for carrying out the method, wherein the apparatus is one for reshaping one or more conductor pieces arranged in a stator core, wherein a plurality of conductor pieces is arranged in the stator core, and is arranged on a plurality of circular paths running in a circumferential direction in rows which extend along a radial direction, wherein the reshaping takes place in a free end of the conductor piece projecting out of the stator core, wherein the apparatus comprises: a receptacle for the stator core in a provided machining position in which the conductor pieces to be reshaped are arranged in an initial configuration before reshaping such that the conductor pieces projecting from the stator core project extended along a longitudinal direction out of the stator core; at least one bending unit for reshaping the conductor piece or pieces, wherein the bending unit in turn comprises: a positioning unit for positioning the bending unit relative to the receptacle for the stator core a contact portion which is configured to laterally contact the one or more conductor pieces to be reshaped; an actuator which is arranged and configured to move the contact portion relative to the positioning unit in order to reshape the conductor piece or pieces; characterized in that the contact portion is mounted in the positioning unit in such a way that when the actuator is actuated, the contact portion is moved in a first movement step relative to the positioning unit in a first bending direction without changing its pivot positioning and in a second movement step, the movement of the contact portion in the first bending direction is superimposed with a pivoting movement.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Further features, details and advantages of the invention can be found in the wording of the claims and in the following description of the embodiments with reference to the drawings, in which:

[0078] FIG. 1 is a side view of a bending unit and a counter-bearing device of an apparatus according to the invention;

[0079] FIG. 2 is a perspective view of the bending unit and the counter-bearing device according to FIG. 1;

[0080] FIG. 3 is a side view of the bending unit and the counter-bearing device according to FIG. 1 in a further state;

[0081] FIG. 4 is a side view of the bending unit and the counter-bearing device according to FIG. 1 in a further state;

[0082] FIG. 5 is a top view of an arrangement of a plurality of bending units according to FIG. 1 of a further apparatus according to the invention;

[0083] FIG. 6 is a top view of an arrangement of a bending unit according to FIG. 1 of a further apparatus according to the invention; and

[0084] FIG. 7 is a top view of an arrangement of a plurality of bending units according to FIG. 1 of a further apparatus according to the invention;

[0085] FIG. 8 is a schematic representation of a contact portion;

[0086] FIG. 9 is a further schematic representation of the contact portion from FIG. 8;

[0087] FIG. 10 is a further schematic representation of the contact portion from FIG. 8;

[0088] FIG. 11 is a further schematic representation of the contact portion from FIG. 8;

[0089] FIG. 12 is a schematic representation of an alternative contact portion;

[0090] FIG. 13 is a further schematic representation of the contact portion from FIG. 12;

[0091] FIG. 14 is a schematic representation of an alternative contact portion; and

[0092] FIG. 15 is a sectional view of an alternative contact portion.

DETAILED DESCRIPTION

[0093] In the following description and in the figures, corresponding components and elements have the same reference signs. For the sake of clarity, not all of the reference signs are shown in all of the figures.

[0094] FIG. 1 shows a side view of a bending unit 11 and a counter-bearing device 56 of an apparatus 10 according to the invention and FIG. 2 shows a perspective view of the bending unit 11 and the counter-bearing device 56 according to FIG. 1. The starting position of the apparatus 10 is shown. In this initial position, a stator core 12 and conductor pieces 14 arranged therein are accommodated in a receptacle (not shown) in a provided machining position and conductor pieces to be reshaped have not yet been reshaped.

[0095] The conductor pieces 14 are arranged in circular paths 17 running in a circumferential direction 16 in rows 19 in the stator core 12 (see FIG. 5-7). The rows 17 extend along a radial direction 18. The conductor pieces 14 are predominantly so-called hairpins, which have two longitudinally extended members, which in turn are connected to one another via a connecting portion. In the processing position, the conductor pieces 14 to be reshaped (typically members of the hairpins) project out of the stator core 12 along a longitudinal direction 20. This corresponds to the initial configuration of the conductor pieces 14 in which they are located before reshaping. The figures show in each case the free members of the conductor pieces 14, that is to say the longitudinally extended ends of the conductor pieces 14 which face away from any connecting portions that there may be. The stator core 12 can also be seen partially and rather schematically in FIG. 1-4.

[0096] The bending unit 11 has a positioning unit 22. This serves to position the bending unit 11 relative to the receptacle or relative to the stator core 12 arranged in the receptacle (not shown). During the reshaping process or the bending process, the positioning unit 22 is arranged fixedly with respect to the receptacle or the stator core 12.

[0097] The bending unit 11 also has a contact portion 26 which is configured to be able to contact a conductor piece 14 to be reshaped or a plurality of conductor pieces 14 to be reshaped laterally and from above in the direction toward the stator core 12.

[0098] The illustrated contact portion 26 is configured like a sleeve and has a first open end 30. In the operating position, this open end faces the stator core 12. A second closed end 32, opposite the first open end 30, faces away from the stator core 12 in the operating position. The contact portion 26 can thus be placed effectively over a single conductor piece 14 or a plurality of conductor pieces 14, wherein the second closed end 32 forms a stop for the free ends of the conductor pieces 14.

[0099] The contact portion 26 can be moved by means of an actuator 28. The contact portion 26 can be moved in a first bending direction 23 and in a second bending direction 25 by means of the actuator 28.

[0100] In the embodiment shown here, the first bending direction 23 corresponds to the radial direction 18. The second bending direction 25 is counter to the first bending direction 23.

[0101] In this case, the actuator 28 is configured in the form of a linear actuator, which is arranged pivotably on the positioning unit 22 and is also pivotably connected to the contact portion 26.

[0102] The positioning unit 22 includes a frame element 24 which remains stationary with respect to the stator core 12 during the reshaping process or the bending process. A first guide element 34 and a second guide element 36 are arranged in the frame element 24.

[0103] The first guide element 36 extends longitudinally along an extension axis 38. The first guide element 34 is arranged pivotably mounted in the second guide element 36 at a pivot point 40. The two guide elements are thus pivotably connected to one another via this pivot point 40. The only possible relative movement between the two guide elements is therefore a pivoting movement.

[0104] The pivot point 40 is arranged fixed with respect to the second guide element 36.

[0105] The second guide element 36 is arranged in the frame element 24 such that it can be moved in a translatory manner along or counter to the first bending direction 23. This translatory movement of the second guide element 36 is brought about by means of a guide. In the illustrated embodiment, the guide is created by three guide rods 41. The guide rods 41 extend into the second guide element 36, wherein it is possible for the guide element 36 to be displaced along the guide rods 41, as a result of which the second guide element 36 is mounted in a straight line guided along the first bending direction 23 or the second bending direction 25.

[0106] The guide rods 41 extend in their longitudinal orientation along the first bending direction 23 or the second bending direction 25. They are therefore parallel to each other. The guide rods 41 are fixedly arranged on the frame element 24.

[0107] Because the pivot point 40 is fixedly arranged in relation to the second guide element 36, it follows the translatory movement of the second guide element 36. Correspondingly, when the second guide element 36 moves, the pivot point 40 and thus also the first guide element 34 are moved relative to the frame element 24 or to the positioning unit 22.

[0108] The frame element 24 is U-shaped in the broadest sense and delimits a free space in which the first guide element 34 and the second guide element 36 are arranged, at least in the first bending direction 23 and the second bending direction 25.

[0109] The frame element 24 includes a first stop 42. This is arranged on the frame element 24 and serves for contacting the first guide element 34 when it is moved in the first bending direction 23.

[0110] The frame element 24 further comprises a second stop 44. It serves for contacting the second guide element 36 when it is moved in the first bending direction 23.

[0111] The first stop 42 and the second stop 44 are on the same side of the frame element 24.

[0112] The frame element 24 includes a third stop 46. This third stop serves for contacting the second guide element 36 when said guide element is moved in the second bending direction 25. Correspondingly, the third stop 46 is arranged on the side of the frame element 24 opposite the first stop 42 and the second stop 44. The second guide element 36 is thus arranged to be movable back and forth between the first stop 42 and the second stop 44.

[0113] Because the frame element 24 is fixed with respect to the stator core 12 during the bending process, all parts fixedly arranged on the frame element 24, such as, for example, the three guide rods 41, the first stop 42, the second stop 44 and the third stop 46, are also arranged so as to be stationary with respect to the stator core 12 during the bending process.

[0114] The second guide element 36 has a fourth stop 48. This fourth stop serves for contacting the first guide element 34 when the guide element is pivoted in the first bending direction 23 about the pivot point 40.

[0115] The second guide element 36 also has a first spring 49 which is arranged on the second guide element 36 in the second bending direction 25. The first guide element 34 is braced against the fourth stop 48 in the first bending direction 23 by means of the first spring 49. This position of the first guide element 34 resting against the fourth stop 48 is also referred to below as the contact position. In this contact position of the first guide element 34 shown in FIG. 1, the first guide element 34 is oriented such that its extension axis 38 is aligned parallel to the longitudinal direction 20 and thus parallel to the free ends of the conductor pieces 14 projecting out of the stator core 12. In particular, the extension axis 38 is arranged orthogonally with respect to the first bending direction 23.

[0116] The first guide element 34 is connected to the contact portion 26 by means of a piston rod 52. The piston rod 52 is arranged within the first guide element 34 and runs along the extension axis 38. The alignment of the piston rod 52 and the contact element 26 thus always corresponds to the alignment of the first guide element 34 or its extension axis 38. If the first guide element 34 is pivoted about the pivot point 40, its extension axis 38 and also the piston rod 52 together with the contact portion 26 pivots about the pivot point 40 accordingly. The piston rod 52 is pretensioned toward the stator core 12 relative to the first guide element 34 by means of a second spring 51. The piston rod 52, and thus also the contact portion 26 on which the piston rod 52 is arranged, can be moved along the extension axis 38 relative to the first guide element 34 against the spring tension. The piston rod 52 is firmly connected to the contact portion 26. A movement of the piston rod 52 is thus transmitted to the contact portion 26.

[0117] The contact portion 26 can therefore both be lowered relative to the frame element 24 or the positioning unit 22 (away from said positioning unit toward the stator core 12) and also moved in the first bending direction 23 and the second bending direction 25. In addition, the contact portion 26 can be pivoted relative to the frame element 24 or the positioning unit 22. In this embodiment, all of this is brought about by means of the actuator 28 articulated on the positioning unit 22. Correspondingly, the actuator 28 is articulated (pivotable) on the frame element 24 or the positioning unit 22. The actuator 28 is also pivotably connected to the contact portion 26 by means of a joint 54. In this case, the joint 54 is designed as a fork head, with which the contact portion 26 is connected in a pivotably mounted arrangement. On the other hand, the actuator 28 is arranged pivotably on the frame element 24 in order in particular to be able to follow the movement of the contact portion 26 along the extension axis 38.

[0118] The contact portion 26 can therefore perform a plurality of movements relative to the frame element 24 or the positioning unit 22. A first movement (or type of movement) is a translatory movement along the first bending direction 23 or the second bending direction 25. A second movement is a translatory movement along the extension axis 38. A third movement is a pivoting of the contact portion 26 about the pivot point 40 (wherein the extension axis 38 is also pivoted at the same time).

[0119] During the bending process, the contact portion 26 performs a movement that results from a superimposition of these three movements.

[0120] When the contact portion 26 is lowered onto the conductor pieces 14, the free ends of the conductor pieces 14 bump against the closed end of the contact portion 26 and move it against the pretensioning by the second spring 51 along the extension axis 38 toward the frame element 24. Correspondingly, when the conductor pieces 14 shorten their extension from the stator core 12 to the positioning unit 22 due to the radially outwardly directed bending, the contact portion 26 is kept in contact with the free ends of the conductor pieces 14 by the spring 51 and moved along the extension axis 38 from the frame element 24 toward the stator core 12. There is effectively a length compensation.

[0121] In the first movement step, there is only a translatory movement along the first bending direction 23 and along the extension axis 38. In the second movement step, the pivoting movement about pivot point 40 is also superimposed.

[0122] The second guide element 36 includes a fifth stop 50. This serves for contacting the first guide element 34 when it is pivoted in the second bending direction 25. It effectively limits its pivotability.

[0123] The stops are adjustable in their position (e.g., can be changed in length by means of a tool).

[0124] The apparatus 10 further comprises a counter-bearing device 56. The counter-bearing device 56 has a counter bearing portion 58. In this case, the counter-bearing device 56 is arranged and supported in the apparatus 10 such that its counter-bearing portion 58 can be placed against the radially outermost conductor piece 14. A first bending point 60 is defined by the counter-bearing portion 58 being placed against the conductor piece 14.

[0125] The counter-bearing device 56, the actuator 28 and the frame element 14 are arranged essentially in one plane. This leads to a particularly narrow design of the bending unit 11 and/or of the apparatus 10.

[0126] FIG. 3 shows a side view of the bending unit 11 and the counter-bearing device 56 according to FIG. 1 in a further state. The position of the bending unit 11 has been changed toward the stator core 12 compared to the initial position shown in FIGS. 1 and 2; in other words, the bending unit has been moved toward the stator core, lowered onto the stator core in the illustration shown in the figures. However, an arrangement of the bending unit underneath (lowering the stator core or raising the bending unit) to the side (moving the stator core and bending unit toward one another) of the stator is also within the meaning of the invention.

[0127] By lowering (generally, changing the relative position with respect to one another), the contact portion 26 was moved over the two outermost conductor pieces 14 or, in this case, radially outermost conductor pieces 14, in the first bending direction 23, or it was received in the contact portion 26. The positioning unit 22 has been moved far enough in the direction of the stator core 12 that these two conductor pieces 14 are received with their end portions 62 in the contact portion 26.

[0128] The extension of the end portion 62 in the longitudinal direction corresponds to the part of the conductor pieces 14 received in the contact portion, i.e., the inner extension of the contact portion 26 in the longitudinal direction. The closed end 32 of the contact portion 26 forms a stop in the longitudinal direction 20 for the free ends of the conductor pieces 14.

[0129] In addition, the positioning unit 22 was moved far enough in the direction of the stator core 12 that the second spring 51 is braced in the longitudinal direction 20 by the pressing of the contact portion 26 and thus of the piston rod 52. In this way, the free ends of the conductor pieces 14 received or contacted in the contact portion 26 are subjected to a force in the direction of the stator core 12.

[0130] The end portions 62 are clamped in the contact portion in the lateral direction. This can be recognized by the change in the position of an extension 63 of a clamping device 65 arranged in the contact portion 26 that projects out of the contact portion 26. The clamping device 65 is configured in such a way that the conductor pieces located in the contact portion 26 are pressed from the inside against the radially inwardly arranged wall of the contact portion and bear against it.

[0131] The counter-bearing device 56 was moved in FIG. 3 in the direction of the stator core 12 such that the counter-bearing portion 58 bears against the conductor piece 14 that is outermost in the first bending direction 23 and thus spatially defines the first bending point 60.

[0132] By moving the contact portion 26 between the individual conductor pieces 14, a small gap is created between the conductor pieces 14 to be reshaped and the remaining conductor pieces 14 in the row 19. For this purpose, the contact portion 26 in this case has a rounded edge 66. The edge 66 is rounded, wherein the rounding in this case is created by a semicircular cross section. In this case, this is configured with a radius of 0.5 mm. Other cross sections tapering toward the conductor pieces are also within the meaning of the invention. The edge 66 also defines the second bending point 64, which will be discussed further below.

[0133] The conductor pieces 14 received or contacted by the contact portion 26 are therefore already minimally bent around the first bending point 60. However, this bending is negligible, and this bending is not what is referred to when the bending and/or reshaping process is mentioned.

[0134] From this starting position of the apparatus 10 shown in FIG. 3, the actual bending process is started.

[0135] FIG. 4 shows a side view of the bending unit 11 and the counter-bearing device 56 according to FIG. 1 in a further state. The final position of the apparatus 10 can be seen after the bending process has been carried out.

[0136] The bending process is started by actuating the actuator 28. The actuator 28 moves the contact portion 26 in the first bending direction 23. Because the contact portion 26 is connected to the first guide element 34 via the piston rod 52, said element is also moved in the first bending direction 23.

[0137] The first guide element 34 is connected to the second guide element 36 via the pivot point 40 and in the contact position is braced against the fourth stop 48 by means of the first spring 49. As a result, the movement of the first guide element 34 in the first bending direction 23 is transferred to the second guide element 36. The second guide element 36 is guided in a straight line by the three guide rods 41 parallel to the first bending direction 23 and second bending direction 25, respectively. The contact portion 26, the piston rod 52, the first guide element 34 and the second guide element 36 move in a first movement step in the first bending direction 23.

[0138] The conductor pieces 14 received or contacted in the contact portion 26 are likewise moved in the first bending direction 23. These conductor pieces 14 are bent in the first bending direction 23 around the first bending point 60. A second flex point 64 is defined by the edge 66 of the contact portion 26. The conductor pieces 14 received in the contact portion 26 or contacted thereby are in contact with the contact portion 26 along their end portions 62 and in the contact portion 26 are fixed in their alignment with respect thereto. Thus, the movement of the contact portion 26 in the first bending direction 23 shifts the end portions 62 in a translatory manner (the direction will be explained in more detail later). The orientation of the end portions 62 remains parallel to the longitudinal direction 20, so that the end portions are bent during the movement (1st movement step) of the contact portion 26 in the first bending direction 23 around the second bending point 64 with respect to the central portions (between the first and second bending points) in the second bending direction 25. The conductor pieces 14 are widened by the first and second bends that are created in this way.

[0139] During the first movement step of the bending process, the free ends of the conductor pieces 14 received or contacted in the contact portion 26, due to geometry, move in the direction of the stator core 12. The second bending point 64 therefore moves toward the stator core 12. In other words, the expanded conductor pieces 14 become shorter in relation to the longitudinal direction 20 as a result of the bending. Because the contact portion 26 is acted upon by the second spring 51 via the piston rod 52 in the direction of the stator core 12, the contact portion 26 follows this movement of the free ends of the conductor pieces 14, so that throughout the bending process the end portions 62 are accommodated in the contact portion 26 or contacted by them. In other words, the end portions 62 of the conductor pieces 14 do not move relative to the contact portion 26.

[0140] The contact portion 26, the piston rod 52, the first guide element 34 and the second guide element 36 are moved in the first bending direction 23 until the first guide element 34 bumps against the first stop 42. As the contact portion 26, the piston rod 52 and the second guide element are moved further in the first bending direction 23, the first stop 42 forces the first guide element 34 to pivot relative to the second guide element 36 in the second bending direction and about the pivot point 40. The pivot point 40 is stationary with respect to the second guide element 36 and thus also moves in the first bending direction. In this second movement step of the bending process, the piston rod 52 arranged therein and thus also the contact portion 26 are also pivoted when the first guide element 34 is pivoted. The end portions 62 of the conductor pieces 14 received or contacted in the contact portion 26 are also pivoted in the second bending direction 25. The pivoting process is ended by the fifth stop 50. The first guide element 34 pivots in the second bending direction 25 until the first guide element 34 hits the fifth stop 50, which is arranged so as to be stationary on the second guide element 36, and thus reaches its final pivot position. Finally, the second movement step ends when the second guide element 36 contacts the second stop 44.

[0141] As a result of the first movement step in the first bending direction 23, the conductor pieces 14 received or contacted in the contact portion 26 are moved far enough in the first bending direction 23 that there is enough space for the pivoting process in the second bending direction 25 of the second movement step for the end portions 62 of the conductor pieces 14 received or contacted by the contact portion 26.

[0142] After the second movement step, the positioning unit 11 and the counter-bearing device 56 are moved away from the stator core 12, so that the reshaped (expanded) conductor pieces 14 are released.

[0143] The orientation of the end portions 62 of the widened conductor pieces 14 is inclined with respect to the longitudinal axis 20 after the second movement step or the pivoting in the second bending direction 25. Due to the springback of the material of the conductor pieces 14 around the first and second bending point, the end portions 62 of the widened conductor pieces 14 pivot back again against the bending that was carried out, so that the orientation of the end portions 62 of the widened conductor pieces 14 is usually parallel to the longitudinal axis 20 again.

[0144] FIG. 5 shows a top view of an arrangement of a plurality of bending units 11 of a further apparatus 10 according to the invention. The bending unit 11 involves bending units 11 according to FIG. 1. Due to the narrow design of the bending units 11, a plurality of the bending units 11 can be arranged in a radially extending manner and distributed around the stator core 12 in the circumferential direction. An arrangement with six bending units 11 is shown in FIG. 5. A simultaneous expansion of one conductor piece 14 or a plurality of conductor pieces 14 on six rows 19 of conductor pieces 14 is thus possible at the same time. The available installation space can thus be optimally used. The space between the bending units 11 shown can be used, for example, by an arrangement of further machines and/or tools.

[0145] It is also conceivable to arrange the bending unit 11 in such a way that the innermost conductor piece 14 in a row 19 of conductor pieces 14 or a plurality of inner conductor pieces 14 can be widened inward in the radial direction, i.e., counter to the radial direction 18. Here, too, a plurality of bending units 11 can be arranged in a space-saving manner radially around the stator core 12 due to their compact and, in particular, narrow design.

[0146] FIG. 6 shows a top view of an arrangement of a bending unit 11 of a further apparatus 10 according to the invention. The bending unit 11 shown here involves a bending units 11 according to FIG. 1. A tangential arrangement of the bending unit 11 on the stator core 12 can be seen. This allows a conductor piece 14 or a plurality of conductor pieces 14 to be widened in the circumferential direction, that is to say orthogonally to the radial direction 18. Here, too, a plurality of bending units 11 can be optimally arranged on the stator core 12 due to the compact design of the bending unit 11.

[0147] FIG. 7 shows a top view of an arrangement of a plurality of bending units 11 of a further apparatus 10 according to the invention. The bending unit 11 involves bending units 11 according to FIG. 1. A tangential and a radial arrangement of the bending units 11 in combination with one another can be seen. In this way, a plurality of conductor pieces 14 can be expanded simultaneously along the radial direction 18 and orthogonally thereto.

[0148] In the apparatuses such as, for example, according to FIGS. 5 to 7, the stator core 12 can be rotatably arranged so that the individual rows 19 can each be moved under the bending units 11 by a rotation of the stator core 12. Additionally or alternatively, the bending units 11 can be movably arranged in the apparatus.

[0149] FIGS. 8 to 11 show a contact portion 26 as can be used for carrying out the method according to the invention and in the apparatuses 10 according to the invention.

[0150] The contact portion has an edge 66 that tapers toward the conductor pieces 14. The edge 66 serves for the engagement between adjacent conductor pieces 14.

[0151] In the illustration of FIG. 8, the edge 66 grips directly between two adjacent conductor pieces 14 and spreads the radially outer conductor pieces 14 slightly away from the radially inner conductor pieces 14. The radially outer conductor pieces 14 are then accommodated in the contact portion which is shown in FIG. 9.

[0152] The contact portion 26 comprises a clamping device 65. In this embodiment, the clamping device 65 in turn comprises a clamping element 70 which is arranged braced by a spring 72 in a receiving region 74, which is configured in this case as a blind-hole-like receptacle. A clamping surface 76 of the clamping element 70 is spring-biased in the direction of an inner contact wall 68 of the contact portion. Adjoining the clamping surface 76, the clamping element 70 comprises an inclined insertion surface 80.

[0153] The inclined insertion surface 80 is arranged and configured in such a way that, when the conductor pieces 14 contact the insertion surface 80, the clamping element 70 is pushed away from the contact wall 68 against the spring bias until the conductor pieces are clamped or kept clamping between the clamping surface 76 and the contact wall 68. The free ends of the conductor pieces 14 are then in contact with an upper wall of the receiving region 74, which effectively forms a vertical stop and defines the extension of the end portion 62 received in the contact portion or its receiving region.

[0154] FIG. 10 illustrates the end position after the first evaluation step has been carried out. This is followed by the second movement step, the end position of which is illustrated in FIG. 11.

[0155] FIGS. 12 and 13 show an alternative contact portion 26 as can be used for carrying out the methods according to the invention and in the apparatuses 10 according to the invention. The contact portion 26 or its receiving region 74 is open at the top, so that the conductor pieces 14 can be inserted through the receiving region 74. In the recorded state, its configuration corresponds to that shown in FIG. 13. FIG. 13 corresponds here to the end of the first movement step, similar to that shown in FIG. 10.

[0156] FIG. 14 shows a further alternative contact portion 26, as can be used to carry out the method according to the invention and in the apparatuses 10 according to the invention. On the one hand, this contact portion has a slightly differently configured edge 66, which is formed more like a semicircle, while the edge 66 of FIG. 8-13 in each case has a rounded hook shape. The shape of the edge 66 here can also be configured differently in the respective contact portions 26. In particular, the edge is rounded in each case and/or, in particular on its side facing the conductor pieces, it tapers toward them. On the other hand, the contact portion 26 from FIG. 14 also has no clamping device 65. The contact portion 26 has a receiving region 74 which is matched to the dimensions of two conductor pieces 14 (the number can be varied depending on the application) and has a width such that the two conductor pieces 14 can be passed through the receiving region 74 and then be contacted laterally from both sides by the two side walls of the receiving region 74. It is also possible to use such a contact portion 26 in order to use the one top wall which forms a certain vertical stop (as shown in the example of FIG. 8-11).

[0157] FIG. 15 shows a further alternative contact portion 26 in a sectional illustration as can be used for carrying out the method according to the invention and in the apparatuses 10 according to the invention. This contact portion 26 has an edge 66 offset from the conductor pieces relative to the embodiment of FIG. 14.