EP3554730A1

EP3554730A1 - Method for bending extruded profiled elements

Info

Publication number: EP3554730A1
Application number: EP17835609.3A
Authority: EP
Inventors: Markus Werner
Original assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Current assignee: Fraunhofer Gesellschaft zur Forderung der Angewandten Forschung eV
Priority date: 2016-12-13
Filing date: 2017-12-13
Publication date: 2019-10-23
Anticipated expiration: 2037-12-13
Also published as: DE102016224837A1; EP3554730C0; WO2018109017A1; EP3554730B1

Abstract

The invention relates to a method for bending extruded profiled elements (1), in particular a method for the edgewise bending or winding of predominately flat profiled elements with adapted cross-sections. The aim of the invention is to provide a bent extruded profiled element (1) with an approximately constant cross-section and a minimized stacking height as simply and inexpensively as possible. This is achieved in that the method according to the invention for bending extruded profiled elements (1) has the following steps: - step A: providing an extruded profiled element (1) that extends along a profiled element axis (A) and comprises at least one profiled section (2) in which the centroid (F2) of the cross-sectional shape (Q2) is offset relative to the profiled element axis (A); and - step B: bending the at least one profiled section (2') such that the centroid (F2') of the cross-sectional shape (Q2') is moved in the direction of the profiled axis (A) and/or coincides with the profiled element axis (A).

Description

Method for bending deformation of extruded profiles

The present invention relates to a method for bending deformation of extruded profiles, and in particular to a method for producing an electrotechnical coil by bending deformation of extruded profiles according to this method.

The technical problem to be solved by the present invention is the change in cross section or deformation during bending of extruded profiles, in particular in edgewise bending of flat profiles with narrow radii. This concerns the edgewise bending of single sheets between section-wise straight profile sections as well as the continuous bending, here called edgewise wrapping, of endless profiles. The profiles to be bent are referred to in the context of this invention as extruded profiles.

To increase the performance of electrical machines, such as generators, electric motors, and other power components, such as transformers and chokes, more and more coils of round wire are replaced by coils of rectangular wire or wires with adapted cross-sections. As a result, the fill factor of packetized round wires of about 55% can be increased to an order of 90%. In addition, the gap, which is otherwise filled with air, is avoided. This increases the heat dissipation, which results in better cooling of the coil power sections and can be used to increase performance.

When edgewise bending or edgewise winding of extruded profiles changes their profile cross section in a curved profile section adversely, especially at tight bending radii and high ratios of profile width to height. In general, while the outer arc is thinned at the bending outside of the extruded profile by the extension, whereas the inner arc is compressed at the bending inner side of the extruded profile and thus thickened. The change in cross section means that in the production of an electrical coil by edgewise bending or winding a flat extruded profile, the stack height of the package - and thus the necessary space - grows. Much more disadvantageous, however, is the loss of large-area contact between adjacent windings for heat dissipation. In Figure 1, the changes of the cross-sectional shape and the stack height per turn of the extruded profile by views before (Q, H) and after (Q ', H') of the bending deformation are shown, wherein the surface contact between the individual turns is reduced to a line contact on the inner arc.

Another technical problem of the same nature relates to the production of narrow laminated cores made of strip material, as shown schematically in FIG. By simply winding or bending the outer sheet thins out and there are deviations from the ideal rectangular Cross-sectional shape. When stacking such individual turns with a different cross-sectional shape (Q ') and joining a rotor (L), these move, or can not be arranged as desired.

So far, the change in cross section in tortuous laminated cores has been accepted or selectively adjusted, as from DE 1 037 574 B, DE 270 52 06 A1, DE 103 58 693 A1, US 2,845,555 A and US 3,708,706 A can be seen. The same applies likewise to form coils made of conductor material.

For wound coils, as a rule, the change in the cross section is also accepted in edgewise bending. To stabilize the corner areas, support disks are sometimes used, as in EP 2 301 050 B1. This prevents buckling and also reduces the thickening on the inner bow. Nevertheless, the flat conductor cross-section changes locally from ideal rectangular to trapezoidal.

By pressing the area with changes in cross section, the elevation on the inner arc can be pressed flat, so that the disadvantage of increasing the stacking is avoided. However, this is expensive and leads to inhomogeneous cross sections along the extruded profile.

Another approach for avoiding the elevation on the inner arc is the superposition of edgewise bending with axial tensile stresses, as shown schematically in Figures 3 and 4 by means of an extruded profile (1) with different sections (1 a, 1 b, 1 c). An edgewise bending superimposed with axial tensile stresses (in section 1b) makes it possible to displace the neutral bending fiber from the central layer (NF ') to the inner curve (NF ") so that the thickening of the inner curve in the bending-deformed cross-sectional shape (Q') compared to the pure edgewise bending (Q ") can be reduced. However, the outer bow thins out all the more. This avoids the increase in the stack height. The small surface contact for heat dissipation remains due to the changed and deviating from the ideal rectangular shape cross-sectional shape (Q '; Q ") but as a critical disadvantage.

The present invention is based on the object to provide a method for bending deformation of extruded profiles while avoiding the disadvantages known from the prior art in order to produce a bend-deformed extruded profile with approximately constant cross-section and minimized stack height as simple and inexpensive.

To achieve this object, the invention provides the method for bending deformation of extruded profiles according to claim 1, comprising the following steps: Step A: Provision of an extruded profile extending along a profile axis with at least one profile section in which the centroid of the cross-sectional shape is offset with respect to the profile axis.

Step B: Biegeumformung the at least one profile section, so that the centroid of the cross-sectional shape is displaced in the direction of the profile axis and / or coincides with the profile axis.

According to the method of the invention, the inevitable change in cross section of the extruded profile is counteracted by the fact that a complementarily adapted cross-sectional shape is kept in the profile section to be bent.

According to the invention, the centroid of the cross-sectional shape of the extruded profile is offset in the profile section to be bent with respect to the profile axis. This means that the area centroid of the cross-sectional shape in the profile section to be bent does not coincide with the profile axis, because the material is arranged unevenly before the bending deformation with respect to the profile axis and is located predominantly in half of the designated bending outside.

In the case of bending deformation, the extruded profile is compressed on the inside of the bend (inner bend) and thinned out on the outside of the bend (outer bend) so that the centroid moves in the direction of the inside of the bend. After the bending deformation has taken place, the centroid of the cross-sectional shape of the extruded profile in the profile section ideally coincides with the profile axis of the extruded profile.

terms and definitions

Cross-sectional shape

The cross-sectional shape of the extruded profile refers in the context of this invention description to a cross section perpendicular to the profile axis of the extruded profile, unless it is explicitly stated otherwise.

Extruded profile, flat profile, profile axis

The term extruded profile is intended to cover all profiles which can be processed by the method according to the invention and subjected to bending deformation, ie in particular endless profiles and strip materials, etc. The extruded profile extends along a profile axis and preferably consists of homogeneous material, for example an electroweld. electrically conductive material such as metal, in particular copper, aluminum, iron, silver or an alloy thereof. The extruded profile is preferably produced by extrusion (or extrusion in the case of a plastic extruded profile), for example with a constant cross-section along the profile axis. In preparation for a sequential bending deformation local cross-sectional changes can be made, for example by local material application and / or material removal.

The ratio of the dimension of the cross-sectional shape in the bending plane to the dimension of the cross-sectional shape perpendicular to the bending plane is preferably greater than 1 before and / or after the bending deformation, and is preferably at least 2, 3, 4, 5 or more.

In the case of a flat profile, the profile width (dimension of the cross-sectional shape in the bending plane) before and / or after the bending deformation is greater than the profile height (dimension of the cross-sectional shape perpendicular to the bending plane).

The profile axis preferably corresponds to the center of the maximum outer dimensions of the cross-sectional shape or the center of the smallest rectangle, in which the cross-sectional shape of the extruded profile fits. In a rectangular cross-sectional shape of the extruded profile in the profile section of the centroid coincides with the profile axis. In a triangular or trapezoidal cross-sectional shape of the extruded profile in the profile section, the centroid with respect to the profile axis is offset in each case in the direction of the wider side of the cross-sectional shape.

Centroid

The centroid of the cross-sectional shape of the extruded profile is the geometric center of gravity of this cross-sectional shape. Mathematically, this corresponds to the averaging of all points within the cross-sectional shape. The centroid can be obtained in simple cases by geometric considerations, or generally calculated by means of mathematics through integration. For the description of the bodies, the methods of analytical geometry are used.

Designated bending section or profile section to be bent

The designated bending section or the profile section to be bent is that section of the extruded profile in which a bending deformation will take place as intended, before the bending has taken place. The designated Biegeaußenseite is that side of the extruded profile, which describes the outer bend of the bend after the intended bending deformation of the extruded profile, but before the bending deformation is done. The bending outside is remote from the center of curvature of the bending deformation.

The designated bending inside is the side of the extruded profile, which describes the inner bend of the bend after the intended bending deformation of the extruded profile, but before the bending deformation is carried out. The bending inner side faces the center of curvature of the bending deformation.

The bending plane is the plane in which the profile axis of the extruded profile is after bending deformation.

Edgewise bending, upright winding

The present invention relates in particular to the bending of an extruded profile in single sheets (edgewise bending) or with a continuous bending radius (edgewise winding) around the side of the extruded profile with a shorter dimension. The dimension / extension of the cross-sectional shape in or along the bending plane is preferably greater than the dimension / extension of the cross-sectional shape perpendicular to the bending plane.

Advantageous developments of the invention are subject matters of the subclaims

It may be advantageous if the cross-sectional shape of the extruded profile provided in step A in the profile section is tapered, preferably continuous and / or linearly tapered, this cross-sectional shape preferably being symmetrical and / or trapezoidal. Such a cross-sectional shape is comparatively easy to machine, so that after the bending deformation results in a symmetrical and uniform cross-sectional shape of the extruded profile.

It may be helpful to reduce the area of the cross-sectional shape of the extruded profile in the profile section in step B, wherein preferably the ratio of the dimension of this cross-sectional shape in the bending plane to the dimension of this cross-sectional shape increases perpendicular to the bending plane, preferably the dimension of this cross-sectional shape remains constant in the bending plane and / or the dimension of this cross-sectional shape is reduced perpendicular to the bending plane, more preferably, the major axis of this cross-sectional shape (ie, the largest dimension of the cross-sectional shape) before and / or after the bending deformation in the bending plane. As a result, a particularly low stack height and a high slot fill factor can be achieved, in particular in the case of edgewise winding and bending of endless profiles. It may be useful if the cross-sectional shape of the extruded profile in the profile section is changed in step B such that two sides thereof after step B extend exactly or substantially parallel to each other and / or exactly or substantially parallel to the bending plane, this cross-sectional shape after Step B is preferably rectangular and / or symmetrical to the bending plane, wherein preferably before and / or after step B, the dimension of this cross-sectional shape in the bending plane is greater than perpendicular to the bending plane. In this design, the extruded profile can be arranged particularly compact in several turns.

However, it may also be useful if the cross-sectional shape of the extruded profile provided in step A is produced in the profile section by material application and / or material removal, preferably starting from an extruded profile with a constant cross-sectional shape along its profile axis. As a result, extruded profiles can be produced, which are suitable in particular for edgewise bending, whereby windings with alternately curved and straight profile sections can be represented by the bending deformation, wherein, for example, alternating single arcs and straight profile sections follow one another by 90 °.

It may prove helpful if the profile section is arranged between two adjoining neighboring sections along the profile axis, wherein the cross-sectional shape of the extruded profile in the profile section in step B is aligned exactly or substantially to the cross-sectional shape of the extruded profile in the adjacent adjacent sections, wherein the cross-sectional shape of Extruded profile in the adjoining the profile section adjacent sections before and / or after step B is preferably rectangular. Also this feature favors the production of extruded profiles for edgewise bending to produce windings with alternately curved and straight profile sections.

It may be advantageous if, in the extruded profile provided in step A, the offset of the centroid of the cross-sectional shape with respect to the profile axis in the course along the profile axis between adjacent to the profile section adjacent sections over the entire profile section or at least a portion of the profile section is uniform, Offset preferably increases from one of the adjacent adjacent sections and decreases toward the other of the adjacent adjacent sections. In particular, in the production of single sheets between two straight profile sections caused by bending deformation change in cross section of the extruded profile is not uniform over the entire profile section. The change in cross section is greatest at the apex of the bend and smallest at the edge regions of the profile section, in each case adjacent to the adjacent neighboring section. Due to the adapted offset of the area center of gravity of the cross-sectional shape of the extruded profile in the profile section, in which the Set increases starting from one of the adjacent adjacent sections and decreasing hinführend to the other of the adjacent adjacent sections, over the entire profile section after the bending deformation, a substantially uniform cross-sectional shape can be generated.

It may prove advantageous if the extruded profile provided in step A is preferably produced by extrusion with a cross-sectional shape which is mirror-symmetrical with respect to two mutually perpendicular planes, preferably in the form of two mirror-symmetric trapezoids along their shorter or longer parallel sides The extrusion profile is preferably subsequently separated along a plane of symmetry in order to have the cross-sectional shape specified in step A in at least one profile section. This feature facilitates the production of trapezoidal extruded profiles. In connection with the edgewise winding, there is a technical problem in the production of profiles (tapes) with slender trapezoidal cross-sections by means of rolling processes. This is achieved by the individual profiles as a double or multiple profiles, in particular as a double or multiple trapezoidal profiles, manufactured and subsequently separated.

It may prove useful if the bending radius of the bending deformation in step B in the profile section is in the range of 0 to 500%, preferably 0 to 200%, preferably 0 to 100% of the dimension of the cross-sectional shape in the bending plane. With such bending radii, the advantageous effects of the claimed invention are particularly advantageous.

However, it can also be helpful if the bending deformation of the extruded profile carried out in step B takes place in the profile section by rolling. By rolling, particularly uniform cross-sectional shapes can be achieved over the bending area.

It can prove to be practical if the profile axis of the extruded profile before step B forms a straight line and / or after step B a winding with at least one turn.

But it may also be useful if the profile section is bent in step B over the shortest side of its cross-sectional shape. In the so-called edgewise bending / winding, the advantageous effects of the claimed invention are particularly evident.

A further aspect of the invention relates to a method for producing an electrotechnical coil with bending deformation of an electrically conductive extruded profile according to the method according to one of the preceding embodiments, so that the extruded profile preferably has a long of the profile axis uniform cross-sectional shape and / or uniform along the profile axis bending radius or alternately straight and curved sections, wherein the turns of the extruded profile preferably contact surface substantially perpendicular to the bending plane. In the case of alternately straight and bent sections, the bending angle of bending deformation in step B per bend is n bends per turn 3607n, ie 90 ° for four turns per turn, 60 ° for six turns per turn, etc.

Further advantageous developments of the invention will become apparent from combinations of the features disclosed in the claims and figures with features from the description.

Brief description of the drawings

Figure 1 shows schematically the change of a rectangular cross-section of a conventional extruded profile due to the bend forming in edgewise bending and winding according to the prior art, and the resulting reduction of the surface contact of the individual turns and the theoretical increase of the stack per turn by changing the height of the cross section before ( H) and after (Η ') the bend multiplied by the number of turns, wherein the cross section (Q) of the conventional extruded profile before bending deformation is shown in outline in dashed line and the cross section (Q') of the conventional extruded profile the bending deformation is shown in a continuous line and hatched.

FIG. 2 shows the stacking fault that actually occurs during the joining of the winding of the conventional extruded profile with bent cross-section (Q ') according to the prior art from FIG. 1 onto a rotor (L).

Figure 3 shows schematically a straight extruded profile (1) according to the prior art with rectangular cross section, comprising a profile section (1 b) and two along the profile axis adjacent adjacent sections (1 a, 1 c), in plan view from above, i. perpendicular to a designated bending plane.

FIG. 4 schematically shows a plan view of a curved profile (1 ') according to the prior art having rectangular cross sections in the straight neighboring sections (1 a, 1 c) and deformed, trapezoidal cross section (Q', Q ") in the section section (1 b), wherein the cross-sectional shape in the profile section (1 b) differs depending on the bending without (Q ') and with superimposed tensile stress (Q') and the resulting neutral fibers (3a, 3b). FIG. 5 shows in view (a) a perspective and schematic illustration of a straight section of an extruded profile (1) with a profile section (2) between two adjacent sections (3) adjacent to the profile axis, wherein the cross-sectional shape of the extruded profile (1) in the profile section (FIG. 2) is trapezoidal and tapers continuously and steadily from the designated bending outside (BA) to the designated bending inside (Bl); and in view (b) is a perspective and schematic representation of a bent by 90 ° portion of an extruded profile (1) with a continuous uniform rectangular cross-section after bending deformation in the profile section (2), wherein the bending plane the main axis of the cross-sectional shape of the extruded profile (1) before and after the bending includes, wherein the cross-sectional shape of the extruded profile (1) in the profile section (2) after the successful bending to the cross-sectional shape of the extruded profile (1) in the adjacent neighboring sections (3) is aligned and also rectangular.

FIG. 6 shows schematically process chains for producing multiple extruded profiles or

Forming tapes (P2a, P2b) by rolling strips (Pi a), columns (P3a, P3b) of the multi-strand profiles or forming tapes to single-strand profiles or molding bands and subsequent upright winding / bending (P4). Alternatively, it is also possible to realize individual forming belts (P2c) by wire drawing from a round cross-section (P1b).

FIG. 7 shows a plan view (a), a front view (b) and a sectional view (c) of a straight extruded profile (1) with a profile section (2) between two adjoining adjacent sections (3) along the profile axis (A), the cross-sectional shape of Extruded profile (1) in the profile section (2) is trapezoidal and continuously tapers from the designated bending outside (BA) to the designated bending inside (Bl).

Detailed Description of the Preferred Embodiment

The preferred embodiment of the invention will be described below in detail with reference to the accompanying drawings.

The inventive method for bending deformation of extruded profiles 1 is carried out essentially in two steps, namely:

Step A: Provision of an extruded profile 1 extending along a profile axis A with at least one profile section 2, in which the centroid F2 of the cross-sectional shape Q2 is offset with respect to the profile axis A. Step B: Biegeumformung the at least one profile section 2 ', so that the centroid F2' of the cross-sectional shape Q2 'is displaced in the direction of the profile axis A and coincides with the profile axis A.

According to the method of the invention, the inevitable change in cross section of the extruded profile 1 in the profile section 2 due to the bending deformation in step B of the method is counteracted by the fact that already in step A, a complementarily adapted cross-sectional shape is maintained.

In a sequential bending deformation (edgewise bending), the cross-sectional adaptation is correspondingly local, with a continuous bending deformation (edgewise winding), in particular with a constant bending radius, provided along the entire extruded profile 1. In the profile section 2, a corresponding material thickening is made, which is changed during bending so that after bending as in the adjacent neighboring sections 3 and between the bends, the desired ideal rectangular cross-sectional shape Q2 'is present.

In the following, the preferred applications of the claimed invention, namely edgewise bending and upright winding, are considered in detail:

Edgewise bending

In Figure 5, both the profile section 2 locally adapted extruded profile 1 and the curved extruded profile 1 are shown schematically. In the exemplary embodiment according to FIG. 5, the profile section 2 is arranged between two neighboring sections 3 adjacent to the profile axis A, wherein the cross-sectional shape Q2 of the extruded profile 1 in the profile section 2 is exactly or substantially matched to the cross-sectional shape Q3 of the extruded profile 1 in the adjoining neighboring sections 3 by bending deformation becomes.

Figure 7 shows an extruded profile 1 with a corresponding cross-sectional adaptation in the profile section 2 in different views (a), (b) and (c).

As shown in particular in FIG. 7 (c), the cross-sectional shape Q2 of the extruded profile 1 in the profile section 2 is trapezoidal and symmetrical to the designated bending plane B, so that it is continuously and linearly tapered starting from the designated bending outside BA to the designated bending inner side Bl. The major axis of the cross-sectional shape Q2 of the extruded profile 1 in the profile section 2, ie the largest dimension of the cross-sectional shape Q2 of the extruded profile 1, runs in the bending plane B. As a result, the centroid F2 of the cross-sectional shape Q2 in the designated profile section 2 with respect to the profile axis A to the designated bending outside BA added. As shown in FIGS. 7 (a) and (b), the cross-sectional shape Q2 of the extruded profile 1 in the profile section 2 is not uniform along the profile axis A. The profile section 2 is arranged between two neighboring sections 3 adjacent to the profile axis A. In an oblique wedge section 2b, the offset of the centroid F2 of the cross-sectional shape Q2 with respect to the profile axis A in the course along the profile axis A increases from one of the adjoining adjacent sections 3, remains constant in a wedge-shaped central section 2a and increases in a further oblique wedge section 2b the other of the adjacent neighboring sections 3 again. The surfaces of the wedge portions 2b and the center portion 2a are preferably in planes meeting at an imaginary point. This imaginary point preferably corresponds to the later bending / bending center. The described cross-sectional shape Q2 of the extruded profile 1 in the profile section 2, which is suitable in particular for (edgewise) bending of individual sheets alternately with straight adjacent sections 3, can be produced, for example, by applying material to the designated bending exterior BA and / or material removal at the designated bending inner side B1, for example, starting from an extruded profile 1 with a respect to the profile axis A constant cross-sectional shape.

As indicated by the dashed line in Fig. 7 (c), the area of the cross-sectional shape Q2, Q2 'of the extruded profile 1 in the profile section 2, 2' decreases in the bending deformation, wherein the dimension of the cross-sectional shape Q2, Q2 'of the extruded profile 1 in the bending plane B between Biegeaußenseite BA and Biegeinnenseite Bl remains constant, while the dimension of the cross-sectional shape Q2 of the extruded profile 1 is reduced perpendicular to the bending plane B.

By the bending deformation, for example by rolling, the cross-sectional shape Q2 'of the extruded profile 1 in the profile section 2' from trapezoidal to rectangular changed so that the upper and lower sides of the cross-sectional shape Q2 'after the bending deformation exactly parallel to each other and possibly exactly parallel to the bending plane B extend. In this case, the cross-sectional shape Q2 'of the extruded profile 1 in the profile section 2 is adapted to the cross-sectional shape Q3 of the extruded profile 1 in the adjoining neighboring sections 3, so that the cross-sectional shape Q2', Q3 of the extruded profile 1 after the bending deformation both in the profile section 2 and adjacent sections 3 adjacent thereto is rectangular and the main axis of the cross-sectional shape Q2 of the extruded profile 1 in the profile section 2 in the bending plane B runs. The bending center or the bending / bending center is in the present case very close to the bending inside ΒΓ, wherein the bending radius in the profile section 2 'is comparatively small and in the range of 50% to about 100% of the dimension of the cross-sectional shape Q2' in the bending plane B is located. In the bending deformation in step B, the centroid F2 of the cross-sectional shape Q2 is displaced by the amount AFS in the direction of the profile axis A, so that the centroid F2 'of the transformed cross-sectional shape Q2' - as well as the centroid F3 of the cross-sectional shape Q3 in the adjacent sections 3 - after step B ideally coincides with the profile axis A.

While the profile axis A of the extruded profile 1 forms a straight line before step B, the extruded profile 1 comprises after step B a curved in the bending plane B profile section 2 'between two straight neighboring sections 3. In an edgewise bending the bent-formed extruded profile V comprises a plurality of curved profile sections 2', each extending between two adjacent neighboring sections 3. An exemplary coil made according to the method of the invention comprises a plurality of turns each having e.g. four 90 ° bent profile sections 2 ', which alternate with straight neighboring sections 3, wherein the turns of the extruded profile 1 along the winding axis, i. perpendicular to the bending plane, contact surface. In order to realize the local or continuous material accumulation, which leads to an offset of the centroid of the cross-sectional shape Q2 in the profile section 2 to the designated bending outside BA, different methods can be used:

Urformen

- To water

Continuous casting with sequential material accumulations Extrusion with different cross-sections (active matrix) Generative processes (SLM, selective laser melting, sintering) Forming Forging

- free upsetting

- swaging in the die wire drawing (with active die)

- separating, ablation

Milling (cutting with defined cutting edge) Grinding (cutting with undefined edge) - etching (separation by chemical and / or electrical action). The bending itself can be done in different ways. For example by: Rotationszugbiegen

Rotationszugbiegen with superimposed axial tension

Rotationszugbiegen with superimposed pressure by flat jaws

Rotationszugbiegen with superimposed pressure by oscillating rollers (Axgesgesenkwalzen)

Flat rolling of material accumulation.

The most important advantage in edgewise bending of electrically conductive extruded profiles for forming coils is the achievement of the desired ideal rectangular cross-section and the associated high degree of filling and the large-area contact for improved heat dissipation between the individual turns and the external environment. With the degree of filling and the improved heat dissipation, the achievable power density increases, and the material usage for the same performance is minimized.

Depending on the combination of the methods for producing the material accumulation and the realization of the bend, this can be done flexibly. The advantage here is that so different sized coils can be manufactured with different numbers of turns. Only one set of dies, dies and jaws is required per conductor cross-section and bending radius, and thus a wide range of coils can be manufactured. Prototypes and small quantities can be produced economically.

Vertical Wind

For edgewise windings, the extruded profile 1 can be produced entirely by extrusion with a constant cross-sectional shape along the profile axis A, as will be explained below with reference to FIG. Since trapezoidal cross-sections in the extrusion process usually can not be easily produced, a double or multiple profile P2a, P2b is preferably generated from a rectangular profile Pi a, which has a cross-sectional shape corresponding to two mirror-symmetrical trapezoids along their shorter (P2a) or longer parallel sides (P2b) are interconnected. This double or multiple Subject profile P2a, P2b is subsequently separated along a plane of symmetry into two individual profiles P3a, P3b in order to have the cross-sectional shape specified in step A. The profile P4 of an edgewise winding after bending deformation ideally has a uniform cross-sectional shape along the profile axis and a uniform bending radius along the profile axis, so that the turns of the extruded profile 1 can contact each other in the winding direction or perpendicular to the bending plane. The solution for the production of forming tapes for edgewise wrapping is thus to roll a single profile P3a, P3b after separation of a double or even multiple profile P2a, P2b generated from an initially rectangular extruded profile Pi a to produce the profile P4 of a vertical winding while avoiding curvature ,

The most important advantage in the high-speed winding of metal strips to round laminated cores is the achievable material savings. Compared to the punching of single rings made of sheet metal strips, where only a few single percentages of the material used are used, the strip material can be almost completely utilized in edgewise wrapping. Material utilization rates of over 90% are achievable.

By means of a low expenditure on equipment, the material structure in the bend can be analyzed and thus it can be proven with which method this area is manufactured. If a bent round wire P1 b, as shown for example in Figure 6, brought by pressing in the desired cross section P2c, the orientation of the grains is different, as if the extruded profile 1 is produced directly with a cross section in which the centroid F2 of the cross-sectional shape Q2 in the profile section 2 with respect to the profile axis A to the designated bending outside BA is offset.

Main fields of application of the invention are electrical machines (generators, motors, transformers) and components (coils, chokes). Furthermore, the invention can be used advantageously wherever flat profiles must be bent around tight radii and the usual change in the cross-section leads to disadvantages. Such an application field is, for example, the winding of laminated cores of electrical machines from tapes of Electroblech. Due to the customary change of the cross-section, this becomes trapezoidal and is thus unsuitable for stacking and likewise for caking of the layers by means of thin layers. LIST OF REFERENCE NUMBERS

1 extruded profile (before bending deformation in profile section)

1 a-c sections of the extruded profile (before bending deformation) - STATE OF THE ART

V extruded profile (after bending deformation in profile section)

2 profile section (before bending deformation)

2 'profile section (after bending deformation)

3 neighboring section

A profile axis

B bending plane

BA Biegeaußenseite (before bending deformation)

BA Biegeaußenseite (after bending deformation)

Bl bending inside (before bending deformation)

ΒΓ bending inside (after bending deformation)

F2 centroid (before bending deformation)

F2 'centroid (after bending deformation)

H Single winding height (before bending deformation) - STATE OF THE ART

H 'height single turn (after bending deformation) - STATE OF THE ART

L runners - STATE OF THE ART

NF ', "Neutral fiber (bending with / without superimposed tension) - STATE OF THE ART

Q Cross-sectional shape single turn (before bend forming) - STATE OF THE ART

Q ', "Cross-sectional shape single turn (after bending deformation) - STATE OF THE ART

Q2 cross-sectional shape in profile section (before bending deformation)

Q2 'cross-sectional shape in profile section (after bending deformation)

Q3 Cross-sectional shape in the neighboring section

Claims

claims

Method for bending deformation of extruded profiles (1), comprising the steps of: a. Step A: Provision of an extruded profile (1) extending along a profile axis (A) with at least one profile section (2) in which the centroid (F2) of the cross-sectional shape (Q2) is offset with respect to the profile axis (A). b. Step B: Biegeumformung the at least one profile section (2 '), so that the centroid (F2') of the cross-sectional shape (Q2 ') in the direction of the profile axis (A) is displaced and / or coincides with the profile axis (A).

A method according to claim 1, characterized in that the cross-sectional shape (Q2) of the extruded profile (1) provided in step A in the profile section (2) is tapered, preferably continuously and / or linearly tapered, this cross-sectional shape (Q2) is particularly preferably symmetrical and / or is trapezoidal.

Method according to one of the preceding claims, characterized in that the area of the cross-sectional shape (Q2, Q2 ') of the extruded profile (1) in the profile section (2, 2') is reduced in step B, wherein preferably the ratio of the dimension of this cross-sectional shape (Q2 , Q2 ') in the bending plane (B) for dimensioning this cross-sectional shape (Q2, Q2') perpendicular to the bending plane (B) increases, preferably the dimension of this cross-sectional shape (Q2, Q2 ') in the bending plane (B) remains constant and / or the dimension of this cross-sectional shape (Q2) is reduced perpendicular to the bending plane (B), more preferably, the main axis of this cross-sectional shape (Q2) before and / or after the bending deformation in the bending plane (B).

Method according to one of the preceding claims, characterized in that the cross-sectional shape (Q2 ') of the extruded profile (1) in the profile section (2, 2') is changed in step B such that two sides thereof after step B exactly or substantially parallel extend to each other and / or exactly or substantially parallel to the bending plane (B), this cross-sectional shape (Q2 ') after step B is preferably rectangular and / or symmetrical to the bending plane (B), preferably before and / or after step B the Dimension of this cross-sectional shape (Q2, Q2 ') in the bending plane (B) is greater than the dimension perpendicular to the bending plane (B).

Method according to one of the preceding claims, characterized in that the cross-sectional shape (Q2) of the extruded profile (1) in the profile section (2) by Materialauf- 2 trand and / or material removal is produced, preferably starting from an extruded profile (1) with a along its profile axis (A) constant cross-sectional shape.

Method according to one of the preceding claims, characterized in that the profile section (2) between two along the profile axis (A) adjacent neighboring sections (3) is arranged, wherein the cross-sectional shape (Q2) of the extruded profile (1) in the profile section (2) in step B is aligned exactly or substantially with the cross-sectional shape (Q3) of the extruded profile (1) in the adjoining neighboring sections (3), the cross-sectional shape (Q3) of the extruded profile (1) being in the neighboring sections (3) adjoining the profiled section (2). is preferably rectangular with respect to the profile axis (A) before and / or after step B.

Method according to one of the preceding claims, characterized in that in the extruded profile (1) provided in step A, the offset of the centroid (F2) of the cross-sectional shape (Q2) with respect to the profile axis (A) in the course along the profile axis (A) between the the profile section (2) adjacent adjacent sections (3) over the entire profile section (2) or at least a part of the profile section (2) is uniform, wherein the offset preferably from one of the adjacent adjacent sections (3) increases and leads to the other of the adjacent Neighboring sections (3) decreases.

Method according to one of the preceding claims, characterized in that the extruded profile (1) provided in step A is preferably produced by extrusion with a cross-sectional shape which is mirror-symmetrical with respect to two mutually perpendicular planes, preferably in the form of two mirror-symmetrical trapezoids running along their sides shorter or longer parallel sides are connected to each other, wherein the extruded profile (1) is preferably separated later along a plane of symmetry to have in at least one profile section (2) the specified in step A cross-sectional shape.

Method according to one of the preceding claims, characterized in that the bending radius of the bending deformation in step B in the profile section (2) in the range of 0 to 500%, preferably 0 to 200%, preferably 0 to 100% of the dimension of the cross-sectional shape in the bending plane ( B) is.

Method according to one of the preceding claims, characterized in that the bending deformation of the extruded profile (1) carried out in step B takes place in the profile section (2) by rolling. 3

1 1. A method according to any one of the preceding claims, characterized in that the profile axis (A) of the extruded profile (1) before step B forms a straight line and / or after step B a winding with at least one turn.

12. The method according to any one of the preceding claims, characterized in that the profile section (2) is bent in step B over the shortest side of its cross-sectional shape (Q2).

13. A method for producing an electrotechnical coil by bending deformation of an electrically conductive extruded profile (1) according to the method according to one of the preceding claims, so that the extruded profile (1) preferably along the profile axis (A) uniform cross-sectional shape and / or along the profile axis ( A) uniform bending radius or alternately straight and curved sections, wherein the turns of the extruded profile (1) preferably contact surface substantially perpendicular to the bending plane.