EP3622614A1

EP3622614A1 - Method and device for deforming u-shaped electric conductors

Info

Publication number: EP3622614A1
Application number: EP18724231.8A
Authority: EP
Inventors: Pier VAI; Angiolino BENEDETTI; Crescini SILVANO
Original assignee: Gehring E Tech GmbH
Current assignee: Gehring Technologies GmbH and Co KG
Priority date: 2017-05-11
Filing date: 2018-05-11
Publication date: 2020-03-18
Also published as: US11601034B2; CN110603719A; JP6970282B2; DE102017004538A1; US20210135552A1; WO2018206783A1; KR20200018413A; CN110603719B; JP2020520629A

Abstract

The invention relates to a method and a device (1) for deforming a U-shaped electric conductor (6) into a hairpin (19) which can be used to produce a bar winding of an electric machine. Prior to the deforming process, the electric conductor (6) has two parallel limbs (7, 8) which are integrally connected together by means of a connection limb (9), and the three limbs (7, 8, 9) are arranged on an imaginary plane (10). The aim of the invention is to carry out the deformation of the electric conductor (6) into a hairpin (19) in an inexpensive manner. According to the invention, this is achieved in that the two parallel limbs (8, 9) are first clamped in a respective clamping device (A, B), the first limb (7) together with the first clamping device (A) is then held in place, the second limb (8) is then moved away from the first limb (7) on a circular path (42), thereby stretching the connection limb (9), and a deformation section (11') of the electric conductor (6) is simultaneously or subsequently moved on a guide surface (31) of a twisting guide element (30), said guide surface protruding radially beyond the circular path (42).

Description

Title: Method and apparatus for forming U-shaped electrical conductors

description

The invention relates to a method and apparatus for forming a U-shaped and in cross-section angular electrical conductor to a hairpin, which is used for the production of a rod winding of an electric machine, wherein the electrical conductor before the

Forming process has two mutually parallel legs which integrally by means of a connecting leg

connected to each other, and wherein the three legs are arranged in an imaginary, plan level.

In the context of the invention, the term "electric machine" only electric motors and electrical Generators understood that convert electrical energy into mechanical energy or mechanical energy into electrical energy. From DD 47 392 Bl it is known that so-called rod windings are used to produce the winding of high-performance electrical machines. These

Rod windings consist of a large number of solid rods made of a material with good electrical conductivity. After insertion into the grooves of armature or stator lamination packages, the rods are connected to one another such that they form at least one winding strand, depending on the design. According to an embodiment known from GB 200,469 B, the rods used for the construction of a rod winding can have a largely U-shaped geometry, in which two parallel legs are integrally connected to each other by means of a connecting leg. Here is the cross-sectional geometry of the legs

rectangular. Such rods are also known as so-called hairpins. Thus, the two mutually parallel legs of the U-shaped rods in an anchor or

Stator laminated core can be used in radially offset grooves, the known from GB 200,469 B U-shaped rods in the region of these connecting legs from an offset range in which the U-shaped rod is twisted in itself, as will be explained with reference to an embodiment. Moreover, it is known from EP 2 710 715 B1 that, in a conventional method for producing hairpins, first the rod-shaped electrical conductors are their

described U-shaped basic geometry obtained by a first bending operation. Subsequently, in a second forming process, the head of such a conductor, so its connecting leg, formed in a molding press, these two mutually parallel legs are held in that orientation, which for their subsequent placement in associated slots in a laminated core of a stator or armature of an electric machine necessary is. This manufacturing process is considered unfavorable

judged, because after such a procedure

or in a production machine operating according to this method, only hairpins of only one geometry can be produced. If hairpins for the production of another, for example, larger stator or armature, to have a different geometry, the molds of such a machine must be exchanged consuming against other, geometrically appropriate molding tools. In addition, it is judged disadvantageous that the electrical conductor is exposed in such a forming process in a mold a comparatively large mechanical stress, which can lead to damage to the electrical conductor and / or its insulation. Around

To avoid disadvantages, EP 2 710 715 B1 proposes a device and a method for producing hairpins for electrical machines, in which the use of shaping tools in favor of others, according to This assessment is also unfavorable

Forming tools and process steps is omitted.

Against this background, the invention has for its object to provide a method and apparatus with which generic hairpins are cheaper to produce than before. In particular, the device should be constructed such that it is manually operated in the simplest case, but also automatically

can be operated. In addition, the device should be used without much modification for the production of hairpins

be suitable for different size and geometry, so as to produce electric machines overall cheaper than before.

These tasks are through a procedure and a

Device solved, which have the features of the independent claims. Advantageous developments are defined in the respective associated dependent claims.

The invention was based on the finding that a twisted geometry of the connecting portion of a U-shaped electrical conductor, which ensures the same installation in a bar winding of a stator or armature of an electric machine, thereby comparatively easy to produce by first in a preferably first step two mutually parallel and clamped legs of the U-shaped electrical conductor close to the connecting leg and together with this be pivoted approximately perpendicular to that plane plan, which is designed to be clamped between the two parallel legs, and that in a necessary second step then one of the two mutually parallel legs is moved away along with the connecting leg on a circular path of the other, immovably held leg. To an optimal twisting geometry in particular in the area of the connecting leg to

achieve, in this movement of the second leg of the electrical conductor, a portion of the connecting leg is guided on a geometrically specially shaped surface of a twisting guide member. Because of this

Pivoting over a predetermined circle section and the deformation of at least the connecting leg by means of the twisting guide element become the two

parallel legs in exactly those

Orientation and position necessary to be placed in associated slots of a stator lamination stack or lamination stack. Here, the mechanical stress on the electrical conductor is comparatively low.

According to the independent method claim, the invention accordingly relates to a method for forming a U-shaped and rectangular in cross-section electrical conductor, which is used for the production of a bar winding of an electric machine, wherein the electrical conductor before the forming process has two mutually parallel legs through a connecting leg are integrally connected to each other, and in which the three legs are arranged in an imaginary, plan level.

To solve the method-related task is provided that initially the two mutually parallel legs are clamped in each case a clamping device, that then the first leg together with the first

Clamping device is held stationary, that then the second leg moves away on a circular path of the first leg while the connecting leg is stretched, and that simultaneously or temporally following a forming section of the electrical conductor on a

Guide surface of a twisting guide element is moved, which projects radially beyond the circular path. The first clamping device and the twisting guide element are arranged in a fixed relative position to each other.

The guide surface is designed so that after completion of the forming process, the hairpin has the desired shape and the transitions between the various sections of the electrical conductor are as round as possible and have the largest possible radii of curvature in order to minimize the local deformation of the wire and any protective varnish. The guide surface is usually one

Freeform surface.

Characterized in that the second leg of the electrical conductor with respect to the first, stationary and immovable

clamped leg is moved on a circular path, d he second leg rotated about its longitudinal axis, so that, for example, in a cuboidal cross-section of the two legs whose broad and narrow sides are no longer aligned parallel to each other. As a result, that orientation of the wide and narrow

Reached leg sides, which is necessary in order to introduce these two legs in each case a groove of a stator or anchor plate package, which on a

Circular portion thereof in the circumferential direction and radially offset from each other are formed. Moving the

Connecting leg over the guide surface of the mentioned twisting guide element thus allows a

targeted transformation of the connecting leg. The respective geometry formation of the guide surface of the

Verwindungsführungselements and their radial arrangement and pitch-related positioning in the path of movement of the second leg or connecting leg produce the desired deformation of the

Connecting leg of the electrical conductor, which also no tension cracks in the material of the electrical

Ladder causes.

Since the pinching of the two mutually parallel legs, moving the second leg on a

Circular path as well as the radial and pitch-related

Aligning the Verwindungsführungselements preferably by means of a control device controllable

Actuators can, with the method according to the invention in terms of their dimensions and geometry very different generic electrical conductors, so so called hairpins, are produced automatically and without the change of molds cost.

In most embodiments of the bending device according to the invention, the axis of rotation of the pivot arm is present

Beginning of the pivoting movement, which leads to the forming of the U-shaped electrical conductor, outside of one

isosceles triangle whose base is through the

Longitudinal axes of the legs of the U-shaped electrical

Ladder is formed. This statement holds even if the height H of the triangle is much larger than the length L _BA sis of the triangle (H> 10 X LBASIS) ·

According to an advantageous development of this method, it can be provided that the forming section of the

electrical conductor comprising a portion of the second leg and an adjacent portion of the

Connecting leg covers, on such a

Guide surface of the twisting guide member is moved, which has a first surface portion which is formed close to the second leg and on which the radius of the circular path meets, on which the second

Leg is moved, and which a second

Guide portion which extends in the region of the connecting leg and is located radially outside the circular path of the second leg.

This ensures that the transformation of the

Connecting leg and the adjoining portion of the second leg mechanically guided, so not ungührt, takes place, as a result of the

Connecting leg is deformed into a slightly S-shaped geometry, while something projecting from the imaginary plan plane, which had the U-shaped electrical conductor before the beginning of the forming process.

In order to further favor the forming process can be provided that the first leg by means of the first

Clamping device farther away from the

Connecting leg is clamped as this is the case with the second leg by means of the second clamping device. As a result, as a result of the mechanically the most heavily loaded during the forming process connection region between the connecting leg and the second leg advantageously relieved something, because then this formulating process is then also schlußschenkelahes

Material of the first leg available.

Another development of the method according to the invention provides that the second leg is moved on a circular path whose axis of rotation parallel to the

Longitudinal orientation of the two mutually parallel legs oriented and spaced therefrom. This ensures that the free ends of the two parallel legs also after the forming process

with respect to their longitudinal orientation not pivoted against each other, but are aligned parallel to each other.

According to another advantageous variant of the method can be provided that before moving away the second Leg of the first thigh

connecting thigh-shaped forming section of the first

Schenkels towards a clamp base of the first

Clamping device is bent, due to the

Integrity of the electrical conductor also the

Connecting leg is taken. This additional method step relieves the transition region between the first leg and the connecting leg mechanically in the then subsequent forming of the connecting leg by means of the twisting guide element.

Next is to prepare a concrete one

Production process provided that the

Twisting guide element before the production of a series of twisted, U-shaped electrical conductors (ie the generic hairpins) so radially in relation to the axis of rotation of the pivot arm and pivoted about a parallel to the axis of rotation of the pivot arm aligned pivot axis of the torsion guide is pivoted that a certain orientation of the two parallel legs to each other and a certain deformation of the

Connecting leg is achieved in the subsequent production process. The forming process may, according to one example, comprise at least the following process steps:

a) supplying a U-shaped electrical conductor in a forming device, wherein the electrical conductor two parallel legs and one of these connecting connecting legs, which are all arranged in an imaginary plane plan,

b) tightening a clamping portion of the first leg in a first clamping device and tightening a clamping portion of the second leg in a second

Clamping device, wherein these two clamping portions are formed close to the connecting leg,

c) holding the two mutually parallel legs at their respective Einklemmort and bending over a

Forming portion of the first leg, which is formed close to the connecting leg, away from the imaginary planar plane of the electrical conductor,

d) moving the second leg on a circular path whose center lies on the axis of rotation of the pivot arm, this pivot axis of the pivot arm is aligned parallel to the first leg of the electrical conductor, and due to the movement of the second leg stretching the connecting leg of the electrical conductor,

e) moving a portion of the connecting leg on a guide surface of a twisting guide member, wherein at least a surface portion of this guide surface is arranged with respect to the rotational axis of the pivot arm radially outside the Einklemmortes the first leg,

f) and finally releasing the two clamping devices for releasing the converted into a hairpin electrical

Leader.

Preferably, thereafter, the cutting of the hairpin from the rest of the wire takes place, if not already done before clamping the U-shaped wire. To solve the device-related task, a device for forming a U-shaped and in the

Cross section of angular electrical conductor to one

proposed generic hairpin, which is suitable for the production of a rod winding of an electric machine, wherein the electrical conductor two

has mutually parallel legs, which are integrally connected by means of a connecting leg. This device has at least the following:

a device rack,

- One arranged on the device frame, and

relative to the device frame fixed first

Clamping device, by means of which the first leg can be clamped to the device frame,

a pivoting arm rotatable about an axis of rotation, wherein this axis of rotation is aligned parallel to the first leg of the electrical conductor,

- One arranged on the pivot arm second

Clamping device, by means of which the second leg is clamped to the pivot arm,

- And a twisting guide element, which on the

Device frame is attached and at its end close to the second clamping device has a guide surface,

said guide surface having a first surface portion near the second leg, to which the radius of a circular path meets, on which the second leg is moved upon rotation of the pivotal arm,

- And wherein the guide surface a the

Connecting legs near the second surface section which is arranged radially outside the circular path of the second leg.

In this context, it should be noted that the device rack does not have to be stationary. It is important that the first clamping device on the

Device rack is arranged so that the first leg does not move relative to the device frame during the pivoting movement. The same goes for the

Twist guide element, which also on the

Device frame is attached.

The second leg is on the pivot arm in such a way

clamped that he does not move relative to the pivot arm during the pivoting movement, but the

Swinging motion participates.

It is also possible that the device frame carries out the pivoting movement with the twisting guide element and not the swivel arm (kinematic reversal). It is also possible that a part of the pivoting movement of the

Swing arm and part of the pivoting movement of the

Device frame and the twisting guide element is executed. In all three alternatives, the first clamping device and the second clamping device carry the same during the pivoting operation

Relative movement (s) and the twisting guide element is arranged with respect to one of the two clamping device in a fixed relative position, so that the hairpins in according to the invention from the U-shaped electrical conductors (um-) are formed.

The advantageous use of this forming device has already been briefly described. Further description thereof will be made by various

Embodiments.

According to a first development of this forming device can be provided that the two clamping devices each have a first or a third

Actuating device whose actuators, the first leg of the electrical conductor directly or indirectly against a clamping base on the device frame

or can press the second leg against a clamping base on the pivot arm. The mentioned

Actuators are preferably by means of a

Assistive force operable, which can be generated electrically, hydraulically or pneumatically. Accordingly, the

Fixing the two parallel legs of the electrical conductor done without human help, so that

Risks of injury are excluded and the

Manufacturing process is optimized. In addition, it can be provided that at the first

Clamping device and / or on the second clamping device in each case a second adjusting device is present, by means of which the connecting portion of the electrical conductor after clamping the first leg and / or the second leg of the imaginary plane plane between the two parallel legs is bendable away, preferably in the direction of the device frame.

In a further development of the aforementioned adjusting devices is preferably provided that the respective free end of the actuators of the adjusting devices of the two

Clamping devices each having a clamping piece, which are designed for clamping engagement with the respectively associated leg of the electrical conductor, and that the clamping piece of the first clamping device at its side facing the first leg side has such a shoulder that when clamping the first leg to the associated Clamping base at the same time the forming section of the first leg with entrainment of the connecting portion of the electrical conductor from the imaginary plane plane between the two parallel legs towards

Device frame is bendable.

In order to automate the forming device also with regard to the movement of the pivoting arm, it is preferably provided that the pivoting arm directly or via at least one lever with an actuator of a fourth adjusting device

is drivingly connected. In addition, it is preferably provided that the

Twist guide element is pivotable about a pivot axis and axially slidably mounted with respect to its longitudinal direction of the device frame. For adjusting the radial position of the guide surface and the angle of attack of the twisting guide member with respect to the connecting portion of the electrical conductor is preferably provided that the twisting guide member with an actuator of a fifth adjusting device

is connected, by means of which the twisting guide element is pivotable about a pivot axis and / or displaceable with respect to its longitudinal extension direction. It can further be provided that on the

Device frame a pivotable shim is arranged, which serves as a stop for the

Connecting portion of the electrical conductor is used in a clamping of the two mutually parallel legs.

This shim is preferably connected to an actuator of a sixth adjusting device, by means of which the shim is pivotable about a pivot axis such that it is directly about the correct position of the connecting portion of the electrical conductor prior to clamping thereof pivoted.

In addition, it is preferably provided that the axis of rotation of the pivot arm or its pivot bearing is arranged locally adjustable on the device frame. The adjustment range is defined by a coordinate system having two mutually perpendicular geometrical axes which are perpendicular to the longitudinal axis of the stationary clamped first leg of the U-shaped wire are aligned.

Finally, at least some of them are mentioned

Actuators as electric stepper motors

formed, which are connected via control lines with a control device. Alternatively, it may be provided that at least some of the mentioned

Actuators are designed as fluid-operated actuators whose control valves via

Control lines are connected to a control device.

The invention will be explained below with reference to several illustrated in the accompanying drawings embodiments. In the drawing shows

1 is a schematic representation of a known bending device, by means of which a U-shaped electrical conductor can be bent from a wire,

2 is a schematic representation of such an electrical conductor with an imaginary plane plane between the legs of the conductor,

3 shows the electrical conductor according to FIG. 2 with a division of its functional sections, FIG.

4 shows a schematic view of a hairpin, which has been produced after a forming process from an electrical conductor according to FIGS. 2 and 3, and which is usable for producing a bar winding of an electrical machine, FIG. Fig. 5 is a simplified schematic representation of a forming device according to the invention in one

Starting position, by means of a U-shaped

electrical conductor according to the figures 2 or 3, a hairpin according to FIG. 4 is produced,

6 shows the forming device according to FIG. 5 in a schematic side view C in the starting position with a view of the stationarily arranged first leg of the electrical conductor, FIG.

7 shows the forming device according to FIG. 5 during a first contact of the second leg of the electrical conductor with a twisting guide element, FIG.

Fig. 8, the forming device according to FIG. 7 at a continued contact of the second leg of the

electrical conductor with the twisting guide element, Fig. 9, the forming device according to FIG. 8 in a schematic side view with a view of the two

Leg of the electrical conductor,

10 shows the forming device according to FIG. 5 with a stop for adjusting the pinching position of FIG

electrical conductor,

11 shows the forming device according to FIG. 10 in a schematic side view with the stop, FIG.

FIG. 12 shows the forming device according to FIG. 5 with an adjustable pressure piece by means of an actuator, by means of which a forming section of the first leg can be acted on, FIG.

13 shows the forming device according to FIG. 12 in a schematic side view, in which also the actuator can be seen, which acts on the pressure piece, 14 shows a detailed view of the guide surface of the twisting guide element according to FIGS. 5 to 13, FIG. 15 shows a schematic side view of the first clamping device, which has a stepped clamping piece, FIG. 16 shows one of the features of the invention

Forming device in a plan view, shown with an electrical conductor clamped there, in a non-actuated position,

FIG. 17 shows the forming device according to FIG. 16 in a plan view after initial deformation of the first leg of the electrical conductor, FIG

Forming device according to FIG. 16 in a plan view after a final deformation of the electrical conductor to a hairpin and

FIG. 19 shows a reduced representation of FIG. 16 for explaining the relative position of the axis of rotation of FIG

Swivel arm relative to the legs of the electric

Leader. 1 shows a schematic representation of a bending device 1 * known per se, by means of which a U-shaped electrical conductor 6 can be bent out of a wire 2. For this purpose, the wire 2 is fed to a first roller 3 and bent around the surface of the first roller 3 in a circular segment shape by means of a second roller 4. Once the two mutually parallel legs 7, 8 have a desired length, the wire 2 by means of a

Separating device 5 severed and the U-shaped

electrical conductor 6 for further transformation of the

Bender 1 * removed. Deviating from this prior art, this is done

Cutting the wire 2 according to the invention preferably only when the following to be described

Forming process is complete. These

The approach has the advantage that the U-shaped

bent wire 2 only after its final

Shaping must be handled as a single part.

As FIG. 2 shows, the electrical conductor 6 has a largely semicircular connecting leg 9, which integrally connects the two mutually parallel legs 7, 8. The three legs 7, 8, 9 of the electrical conductor 6 are such to each other

aligned so that they span an imaginary plane 10 between them. Such an electrical conductor 6 serves as a preliminary product for producing a hairpin 19 shown in FIG. 4, whose legs 7, 8, 9 no longer lie in the same imaginary plane 10. For this purpose, the electrical conductor 6 must be reshaped, the

Deformation essentially in the area of

Connecting leg 9 is performed so that the two other legs 7, 8 is still a straight

Have geometry, but are no longer arranged in the same imaginary plane.

To such an electrical conductor 6 for producing a bar winding of a stator or armature of a

Electric machine to use with high electrical efficiency, the electrical conductor 6 has a rectangular, preferably cuboid cross-sectional geometry. FIG. FIG. 4 shows one designed as a hairpin 19

electrical conductor 6, whose mutually parallel

Legs 7, 8 each have a narrow longitudinal side 15, 17 and a wide longitudinal side 14, 16 have. In order to use these two legs 7, 8 in each associated grooves in a stator or anchor plate package of an electric machine, have the narrow longitudinal sides 17 and the wide longitudinal sides 14 of the first leg 7 in other directions than the narrow longitudinal sides 15 and the wide

Long sides 16 of the second leg 8. To this

Alignment is realized, the U-shaped electrical conductor 6 in a twisting 18 of the

Connecting leg 9 formed accordingly. As a result, the connecting leg 9, as shown in Fig. 4, a roof-shaped tip 20 or a flat curved

Have geometry.

Before explaining which device and which method proposes the invention for producing a hairpin 19 from an electrical conductor 6, it will be useful for the following description

Defined functional sections of the electrical conductor 6. As illustrated in FIG. 3, the electrical conductor 6 in the connecting region of the connecting leg 9 has a first forming section 11 and a second forming section 11 ', which also has a connecting loop

Section of the two mutually parallel legs 7, 8 include. Farther to the free end, the two parallel legs 7, 8 each have a clamping portion 12, 12 ', which for clamping in an inventive Forming device 1 are provided. This is then followed in each case by a lower section 13, 13 'which extends up to the respective free end of the two parallel ones

Legs 7, 8 extend.

FIGS. 5 to 13 and 16 to 18 show, respectively, seen from different viewing directions and in FIG

different operating positions one

Forming device 1, by means of a U-shaped

electrical conductor 6 can be converted to a hairpin 19, which looks similar to that of FIG. 4.

FIGS. 16 to 18 each best show the overall structure of the forming device 1 in a schematic plan view. Accordingly, the forming device 1, a device frame 21, which all essential

Contributes components of the forming device. These include first two clamping devices A, B, by means of which in each case one of the two mutually parallel legs 7, 8 of a U-shaped electrical conductor 6 at one

correspondingly associated first clamping base 22

or a second clamping base 24 can be clamped. The first clamping base 22 associated with the first clamping device A is fixed to the device frame 21 or integral with it, and serves as an abutment in clamping the first leg 7 of the U-shaped electrical conductor 6. The clamping of this first leg 7 is effected by means of a first Clamping piece 23 which is formed or fixed to the free end of an actuator of a first adjusting device 32. This first adjusting device 32 is designed as Axialaktuator. A second adjusting device 33, also designed as an axial actuator, which is shown only in FIG. 13 and described later, can likewise be arranged at the location of the second clamping device A.

The first adjusting device 32 as well as all other, still to be mentioned adjusting devices are preferably designed as electromotive actuators. But they can also be hydraulic or pneumatic actuators. The respective actuator of the actuators can be moved axially or rotationally. The second clamping device B associated second

Clamping base 24 is a component of a pivoting arm 27 which, according to FIGS. 16 to 18, is pivotably mounted about an axis of rotation 41 on the device frame 21

is arranged. In the simplest case, this is the second one

Clamping base 24 is formed as a recess on the pivot arm 27, which forms a portion of

Cross-sectional geometry of the second parallel leg 8 of the electrical conductor 6 has. The second clamping base 24 thus serves as an abutment when clamping the second leg 8 of the U-shaped electrical conductor 6 on the pivot arm 27. The clamping of this second

Leg 8 is effected by means of a second clamping piece 25 which is formed or fixed to the free end of an actuator of a third adjusting device 34. This third adjusting device 34 is also an axial actuator educated. The housing of this third adjusting device 34 is fixedly connected via a connecting structure 61 with the pivot arm 27, as shown schematically. The pivot arm 27 is attached via a lever 38 and joints 39, 40 to an actuator 37 of a fourth adjusting device 36 ', which also serves as Axialaktuator

is trained. An actuation of the fourth

Actuator 36 'leads to a pivoting movement of the pivot arm 27 about its axis of rotation 41 according to the

Movement direction 46 illustrating double arrow in Fig. 16. Alternatively, it is possible, as shown in Figures 5 to 13, that the fourth actuator 36 is designed as a rotary actuator with a rotation axis 28, and that the rotary actuator 36 forms the pivot bearing of the pivot arm 27.

In addition, a rod-shaped twisting guide member 30 is fixed to the apparatus frame 21. The attachment of this twisting guide member 30 is in the illustrated embodiment such that the

Twisting guide element 30 both in the direction of its longitudinal extent axially adjustable and to a

Arranged perpendicular thereto adjusting axis 49 is pivotally mounted (see local double arrows). An axial adjustment of the twisting guide element 30 is preferably carried out by means of at least a fifth

Actuator 47, which is designed as Axialaktuator and via an actuator 48 with the

Twist guide member 30 is connected. To the leadership the axial displacement of the twisting guide member 30 has this in the illustrated embodiment, a slot 50 which is penetrated by a screwed in the device frame 21 screw. With the

Reference numeral 18 indicates an angle of attack, according to which the twisting guide member 30 is alignable. The setting angle to be set and the axial position of the effective for the deformation of the electrical conductor 6 axial end of the twisting guide member 30 are dependent on the dimensions of the electrical conductor to be deformed 6 as well as the one to be achieved

Deformation geometry of the same.

The twisting guide member 30 has at its

aktuatorfernen end, a guide surface 31, on which the second leg 8 and / or the connecting leg 9 of the clamped electrical conductor 6 under deformation of the same is closely guided. Such a

Deformation process takes place when the clamped by the second clamping device B second leg 8 of the electrical conductor 6 in a pivoting movement of the

Swing arm 27 is moved along a circular path 42 which is at least partially radially within the range of the guide surface 31 of the twisting guide member 30. This will be discussed in more detail, but reference is already made to Fig. 18, which shows how, as a result of such a forming process from the U-shaped electrical conductor 6, a hairpin 19 has been formed for producing a bar winding of a stator or armature of an electric Machine can be used. The Guide surface 31 is designed so that after completion of the forming process, the hairpin has the desired shape and the transitions between the various sections 12, 12 ', 11, 11' of the electrical conductor 6 are as round as possible to the local deformation of the wire and possibly one minimize existing protective coatings. The guide surface 31 is usually a free-form surface.

As shown only in FIG. 16, the forming device 1 can also have a dial 43, which is fastened to the device frame 21 so as to be pivotable about an off-center pivot axis 44. The pivoting of the dial 43 is accomplished by means of a sixth actuator 51, which

is also formed as an axial actuator and is connected via a designed as a coupling rod actuator 52 with the radially outer edge of the shim 43. Upon extension of the actuator 52 is the

Shim 43 turned so far that this

Clamping for the electrical conductor 6 covered just above the connecting leg 9. The local ones

Pivoting directions 45 are indicated by a double arrow

clarified. In a manual or machine

Insertion of the two parallel legs 7, 8 in the associated clamping devices A, B is the

Connecting leg 9 brought with its tip 20 and arcuate top in abutment against the underside of the dial 43, so that the electrical conductor 6 is properly positioned in the two clamping devices A, B, before they are closed. Finally, FIG. 16 shows that all adjusting devices 32, 33, 34, 36, 36 ', 47, 51 of the forming device 1 are connected via dashed control lines to a control device 60, which commands the actuation of these actuators. Its decisions are made by the control device 60, preferably on the basis of sensor information that is not shown

Sensors receives. The described forming device 1 can with a

Method are operated, which has the features of the method claims. For this purpose, reference will now also be made to FIGS. 5 to 15 which schematically illustrate a forming device 1 which is substantially identical to the forming device 1 shown in FIGS. 16 to 18. Only the fourth setting device 36 'operating the pivoting arm 21 is shown in FIGS 15 to simplify the drawing as a rotary actuator 36, so for example as a

Stellmotor drawn, but nothing on the

Principle of operation of the device 1 still on the process for forming an electrical conductor 6 according to the invention changes. Figures 5 and 6 show an initial situation in which a U-shaped electrical conductor 6 with its two mutually parallel legs 7, 8 in a

Forming device 1 designed according to the invention

is clamped. To do this, the two grab

Clamping devices A, B to the associated Clamping sections 12, 12 'of the legs 7, 8, wherein the first adjusting device 32 and the third adjusting device 34 with their respective clamping pieces 23, 25 press the legs 7, 8 to the associated first clamping base 22 and second clamping base 24. As the figures show, the two clamping devices A, B fix the

electrical conductor 6 below the connecting leg 9 as well as below a connection-lying close

Forming section 11, 11 'of the respective parallel legs 7, 8. This ensures that a subsequent deformation of the electrical conductor 6 not only in the

Connecting leg 9 but also in the

connection-shearing forming sections 11, 11 '

can take place. In this initial situation, the unclamped portion of the electrical conductor 6 from the upper edge of the two clamping pieces 23, 25 to the

Upper edge of the connecting leg 9 has a height Hl.

In particular, Fig. 6 shows in a side view C of the forming device 1, that the first leg 7 between the first clamping base 22 and the first pressure piece 23 of the first actuator 32 is arranged, and that designed as Axialaktuator first actuator 32 with the actuator 35 according to the local direction arrow presses against the first leg 7.

Fig. 7 shows a second operating situation of

Forming device 1, in which the pivot arm 27 by means of the fourth adjusting device 36 so far around his

Swivel axis 28 has been pivoted that the electric Head 6, the guide surface 31 of the protruding here from the plane of the twisting guide element 30 just touched. By this pivoting operation, the electrical conductor 6 was in the area of his

Stretched connecting leg 9, so that thereby the height H2 has decreased from the upper edge of the connecting leg 9 up to the upper edge of the two clamping pieces 23, 25. The stretching of the connecting leg 9 as well

optionally the adjacent sections of the two

Legs 7, 8 did not lead to a structural change in the structure

Material of the electrical conductor 6, but only to a change in geometry in said

Connecting leg portion of the electrical conductor 6. Figures 8 and 9 show the inventive

Forming device 1 in an operating situation in which the desired deformation of the electrical conductor. 6

is completed and this now has the geometry of a generic hairpin 19. For this purpose, the fixed to the pivot arm 27 second leg 8 was at a circular movement of its clamping point on the mentioned

Circular path 42 out, and thereby the forming section 11 'of the second leg 8 and the connecting leg 9 with a resulting from the rotational movement of the pivot arm 27 and the geometric conditions contact force on the guide surface 31 of the twisting guide member 30 moves along. Meanwhile, the first leg 7 remained firmly clamped fixed to the device frame 21. The guide surface 31 of the twisting guide member 30 is designed for such and in relation to the circular path 42nd of the first leg 7 positions the electrical conductor 6 on the first contact with the twisting guide element 30 after the first contact shown in FIG

Guide surface 31 is deflected and then bent with deformation of the second deformation portion 11 'with respect to the circular path 42 radially outward. This gives the second deformation portion 11 'of the electrical conductor 6, the geometry of a generic hairpin 19, which is suitable for producing a rod winding of a stator or armature of an electric machine.

The geometry of the hairpin 19 depends inter alia on how large the radius of the circular path 42, to which the second leg 8 is moved during a pivoting movement of the pivot arm 27. In addition, the geometry of the manufactured hairpin 19 of the angle of the

Twist guide element 30 to the connecting leg 9 dependent. In addition, the geometry of the hairpin 19 to be produced is determined by how far the

Guide surface 31 of the twisting guide member 30 extends radially inwardly and radially outside of said circular path 42 of the second leg 8.

According to the embodiment shown in Fig. 14 can therefore be provided that the guide surface 31 of the

Verwindungsführungselements 30 has a second leg 8 of the electrical conductor 6 near first surface portion 53 which is disposed radially within the circular path 42 of the second leg 8, and that the

Guide surface 31 a the connecting leg 9 near second surface portion 54, which radially outside the circular path 42 of the second leg. 8

is arranged. Finally, three further developments of

Forming device 1 according to the invention described. According to FIGS. 10 and 11, the forming device 1 can have a dial instead of the dial 43 shown in FIG. 16

Stop have 29, where the upper, through the

Connecting leg 9 formed end of a U-shaped electrical conductor 6 for adjusting its

Can pinch pinch position. This stop 29 is in the example shown in Figures 10 and 11 by the free end of the actuator 59 of a seventh

Adjusting device 58 is formed, which is also designed here as an axial actuator whose rod-shaped

Actuator 59 can be adjusted toward the upper end (tip 20) of the connecting leg 9. FIGS. 12 and 13 show a variant already indicated further above, in which a total of two in the region of the first clamping device A are used

Axialactuators trained adjusting devices 32, 33 are arranged. By means of the first adjusting device 32, as already described, the first leg 7 of the electrical conductor 6 is fixed in place on the device frame 21. After this is done, by means of the second adjusting device 33 of the forming section 11 of the first leg 7 and the adjacent thereto portion of the connecting leg 9 is slightly in the direction of the Device frame 21 are bent. In the example shown in FIG. 13, a pressure piece 26 of the second adjusting device 33 presses on this forming portion 11 of the first leg 7, which is close to the

Connecting leg 9 is formed. By such a first deformation of the electrical conductor 6, the subsequent forming process on the guide surface 31 of the

Twisted guide element 30 are favored. FIG. 12 shows that also in the area of the third

Adjusting device 34 such a second adjusting device 33 'may be arranged, which can press with a pressure piece 26' against the forming portion 11 'of the second leg 8 and against the adjacent portion of the connecting leg 9 in order to bend this area slightly towards the device frame 21 ,

FIG. 15 shows that a similar deformation process can also be carried out with the first adjusting device 32 if its clamping piece 23 * has a step 56 in the direction of the electrical conductor 6.

In addition, Fig. 18 shows that the axis of rotation 41 of

Swivel arm 27 and its pivot bearing at different locations of the device frame 21st

can be arranged. These different positions are located in a coordinate system which is defined by two geometrically aligned axes x, y. The two axes x, y are perpendicular to the longitudinal axis of the first leg 7 of the U- shaped wire 6 aligned, and the second axis y extends in the illustrated in Fig. 18

Embodiment parallel to the actuator of the first adjusting device 32. The adjustment of the location of the

The axis of rotation 41 of the pivot arm 27 or its pivot bearing takes place on the device frame 21

preferably by means of at least one further, not shown here, the actuator, for example, by a fluid pressure medium or electrically actuated.

Due to the described adjustability of the place of

Rotation axis 41 of the pivot arm 27 and its pivot bearing on the device frame 21 may

Device 1 easy to transform differently sized U-shaped wires 6 to hairpins with different

Radii whose connecting leg 9 and different Verwindungscharakteristik be established.

19, the relative position of the axis of rotation 41 of the pivot arm 27 with respect to the position of the longitudinal axes of the legs 8 and 9 of the electrical conductor 6 is explained in more detail.

FIG. 19 is based on FIG. 17, in which the legs 7, 8 of the electrical conductor are already attached to the first clamping base 22 and the second clamping base 24

are clamped. In FIG. 19, the longitudinal axes of the legs 7, 8 are indicated by crosses 63. If you now through the two longitudinal axes or crosses 63 a

Straight line 65 and at both crosses 63 a straight line 67, 69 erected at an angle of 90 ° with the

Include connecting line 65, then limit this parallel line 67, 69 a surface (without

Reference numeral). Before the pivoting movement begins, the axis of rotation 41 or 28 of the swivel arm 27 is at most

Embodiments of the erfindungsgenmäßen bending device 1 outside this area. In the figure 19 is the

Fulcrum 41 to the left of the limited by the lines 67, 69 area.

When the pivoting movement according to the invention is carried out, the distance between the longitudinal axes of the legs 7, 8 increases because the leg 8 moves on the circular path 42 in the clockwise direction. As a result, the area between the straight lines 67, 69 becomes wider (and changes its

Direction) . After the end of the pivoting movement of the

Fulcrum 41 lie within the area become wider. This results when in the figure 18 the

Crosses marked 63.

You can also do the same thing as follows

If one starts from the in Fig. 19

an isosceles triangle is shown with the crosses 63 representing the base of this triangle, then the axis of rotation 41 of the pivot arm 27 is outside this triangle, it being irrelevant how high the isosceles triangle is. LIST OF REFERENCE NUMBERS

1 device for producing a U-shaped el. conductor

1 * bending device

2 wires

3 first roll (larger diameter)

4 Second roll (smaller diameter)

5 separating device

6 Electric conductor, U-shaped bent wire

7 First leg of the electrical conductor

8 Second leg of the electrical conductor

9 connecting leg of the electrical conductor

10 level between the thighs of the electrical conductor

11 First forming section

11 'Second forming section

12 clamping portion of the first leg

12 'clamping portion of the second leg

13 Lower section of the first leg

13 'Lower section of the second leg

14 width longitudinal side of the first leg

15 Narrow longitudinal side of the first leg

16 width longitudinal side of the second leg

17 Narrow longitudinal side of the second leg

18 Completed twisting section

19 Finished electrical conductor, hairpin

20 bit of finished hairpin 19

21 fixture rack

22 First clamp base 23 First clamping piece

23 * Graded pressure piece

24 Second clamp base

25 second clamping piece

26, 26 'pressure piece

27 swivel arm

28 axis of rotation of the rotary actuator formed as a fourth adjusting device 36th

29 stop

30 twisting guide element

31 guide surface of the twisting guide element

32 First adjusting device (a the first clamping device A)

33 second actuator (a.e the first clamp A) 33 'second actuator (a.d the second clamp B)

34 Third adjusting device (a the second clamping device B)

35 actuator to the first actuator 32nd

36 fourth adjusting device (for the swivel arm);

rotary actuator

36 'fourth actuator (for the swivel arm);

Axialaktuator

37 actuator of the fourth actuator 36 '

38 levers

39 joint on the lever

40 joint on the swivel arm

41 axis of rotation of the pivot arm 27, pivot bearings

42 circular path of the second leg 8

43 shim

44 pivot axis of the shim

45 pivoting direction of the dial 43 46 pivoting direction of the pivot arm 27

47 fifth actuator

48 actuator of the fifth actuator 47th

49 adjusting axis of the twisting guide element

50 slot in the twisting guide element 30th

51 Sixth adjusting device (for the adjusting disk)

52 actuator of the sixth actuator

53 First surface section of the guide surface 31

54 second surface portion of the guide surface 31

56 paragraph on the clamping piece 23 *

58 Seventh adjusting device (for stop 29)

59 actuator of the seventh actuator

60 control device

61 connection structure

63 cross (longitudinal axis of the legs 7, 8 in plan view) 65 connecting line between the longitudinal axes of

leg

67, 69 parallel lines

Setting angle of the pivot arm 27

A first clamping device

B second clamping device

C Viewing direction of the first clamping device A

X First adjustment direction of the rotation axis 41

Y Second adjustment direction of the rotation axis 41

Claims

claims

1. A method for forming a U-shaped electrical conductor (6) to a hairpin (19), which for the

Production of a rod winding of an electric machine is used, wherein the electrical conductor (6) before the forming process two mutually parallel legs (7, 8), which are integrally connected to each other by means of a connecting leg (9), and wherein the three legs (7 , 8, 9) are arranged in an imaginary plane (10), characterized in that

(a) first, the first leg (7) in a first

Clamping device (A) and the second leg (8) are clamped in a second clamping device (B) that (b) then the second clamping device (B) on a

Circular path (42) is pivoted relative to the first clamping device (A), so that the second leg (8) moves away from the first leg (7) and the

Connecting leg (9) is stretched, and that while a forming portion (11 ') of the electrical conductor (6) from a guide surface (31) of a twisting guide member (30) is formed.

2. The method according to claim 1, characterized in that the forming portion (11 ') of the electrical conductor (6), which comprises a region of the second leg (8) and an adjoining region of the connecting leg (9), on a guide surface (31 ) of

Twist guide member (30) is moved, which has a first surface portion (53) which is close to the second leg (8) is formed and on which the radius of that circular path (42) meets, on which the second leg (8) is moved, and which a second

Guide portion (54) which extends in the region of the connecting leg (9) and is located radially outside the circular path (42) of the second leg (8).

3. The method according to claim 1 or 2, characterized

in that the first leg (7) is further away from the first clamping device (A) by means of the first clamping device (A)

Connecting leg (9) is clamped as this is the case with the second leg (8) by means of the second clamping device (B).

4. The method according to claim 1, 2 or 3, characterized

characterized in that the second leg (8) is moved on a circular path (42) whose axis of rotation (41, 28) is oriented parallel to the longitudinal orientation of the two mutually parallel legs (7, 8) and spaced therefrom.

5. The method according to any one of the preceding claims, characterized in that before moving away the second

Leg (8) from the first leg (7)

connecting limb-shaped forming portion (11) of the first leg (7) is bent towards a clamping base (22) of the first clamping device (A).

6. The method according to any one of the preceding claims, characterized in that the twisting guide member (30) before a transformation of U-shaped electrical conductors (6) to hairpins (19) with respect to the axis of rotation (28, 41) of the

Swivel arm (21) radially displaced and about a parallel to the rotation axis (28, 41) of the pivot arm (21) aligned pivot axis (49) of the twisting guide member (30) is pivoted.

7. The method according to any one of the preceding claims, characterized in that between the steps a) and b), the two mutually parallel legs (7, 8) are held at their respective Einklemmort and a

Forming portion (11) of the first leg (7) which is formed close to the connecting leg (9) is bent away from the imaginary plane (10) of the electrical conductor (6).

8. Device (1) for forming a U-shaped

electrical conductor (6) in a hairpin (19), which for the production of a rod winding of an electric

Machine can be used, wherein the electrical conductor (6) has two mutually parallel legs (7, 8), by means of a connecting leg (9) in one piece

interconnected, characterized by

a device frame (21),

a first clamping device (A) arranged on the device frame (21), by means of which the first leg (7) can be clamped to the device frame (21), a pivoting arm (27) which can rotate about a rotation axis (28, 41), this rotation axis (28, 41) being aligned parallel to the first limb (7) of the electrical conductor (6),

- One on the pivot arm (27) arranged second

Clamping device (B), by means of which the second limb (8) can be clamped on the swivel arm (27),

- And a twisting guide member (30) which is fixed to the device frame (21) and at its end to the second clamping device (B) near a guide surface (31).

9. Device (1) for forming a U-shaped

interconnected, characterized by

a first clamping device (A) by means of which the first leg (7) can be clamped,

- An axis of rotation (28, 41), said axis of rotation (28, 41) parallel to the first leg (7) of the electric

Conductor (6) is aligned,

- A second clamping device (B), by means of which the second leg (8) can be clamped,

- And a twisting guide member (30) which opposite the first clamping device (A) in a fixed

Relative position is arranged, with the first

Clamping device (A) and the second clamping device (B) are mutually movable in such a way that the second Clamping device (B) moves in a forming process on a circular path about the axis of rotation (28, 41).

10. Device (1) according to claim 8 or 9, characterized

characterized in that the guide surface (31) has a first surface section (53), which is close to the second leg (8), and to which the radius of a circular path (42) meets, on which the second leg (8) during forming,

in particular when turning the pivot arm (21) or when moving the second clamping device (B), is moved, - and that the guide surface (31) has a

Connecting leg (9) near the second surface portion (54), which is arranged radially outside the circular path (42) of the second leg (8).

11. The device according to claims 8 to 10, characterized in that the first clamping device (A) has a first adjusting device (32) and the second clamping device (B) has a third adjusting device (34) whose actuators (35) the first leg ( 7) of the electrical conductor (6) directly or indirectly against a first

Clamp base (22) or the second leg (8) can press against a second clamping base (24).

12. Device according to claims 8 and 11, characterized in that the first clamping base (22) on the

Device frame (21) and the second clamping base (24) on the pivot arm (27) is arranged.

13. Device according to claims 8 to 12, characterized in that on the first clamping device (A) and / or on the second clamping device (B) in each case a second adjusting device (33, 33 ') is present, by means of which the connecting portion (9 ) of the electrical

Conductor (6) after the clamping of the first leg (7) and / or the second leg (8) from the imaginary flat plane (10) between the two parallel legs (7, 8) is bent away.

14. The apparatus according to claim 13, characterized in that the respective free end of the actuators (35) of the adjusting devices (33, 34) of the two clamping devices (A, B) each have a clamping piece (23, 25), the clamping to the plant the respectively associated leg (7, 8) of the electrical conductor (6) are formed, and that the clamping piece (23 *) of the first clamping device (A) at its side facing the first leg (7) side such a shoulder (56) .

that when clamping the first leg (7) at the associated clamping base (22) at the same time a forming section (11) of the first leg (7) taking along the

Connecting portion (9) of the electrical conductor (6) from the imaginary plane plane (10) between the two

parallel leg (7, 8) towards the device frame (21) is bendable.

15. Device according to one of claims 8 to 14, characterized in that the pivot arm (27) directly or via at least one lever (38) with an actuator of a fourth adjusting device (36, 36 ') drivingly effective

connected is.

16. The device according to one of claims 8 to 15, characterized in that the twisting guide element (30) about a pivot axis (49) is pivotable and axially slidably mounted with respect to its longitudinal extension direction on the device frame (21).

17. The apparatus according to claim 16, characterized in that the twisting guide element (30) with a

Actuator (48) is connected to a fifth adjusting device (47), by means of which the twisting guide element (30) about a pivot axis (49) pivotable and / or axially with respect to its longitudinal direction

is displaceable.

18. Device according to one of claims 8 to 17, characterized in that on the device frame (21) a pivotable shim (43) or a stop (29) is arranged, which serves as a stop for the

Connecting portion (9) when clamping the two

mutually parallel legs (7, 8) of the electrical conductor (6) are used.

19. The apparatus according to claim 18, characterized in that the adjusting disc (43) is connected to an actuator (52) of a sixth adjusting device (51) by means of which the adjusting disc (43) about a pivot axis (44) is pivotable such that these immediately above the correct position of the connecting portion (9) of the electrical conductor (6) is pivotable before clamping it.

20. Device according to one of claims 8 to 19, characterized in that the axis of rotation (41) of the pivot arm (27) or its pivot bearing locally

is adjustably arranged on the device frame (21).

21. Device according to one of claims 8 to 20, characterized in that at least some of the mentioned

Actuators (32, 33, 34, 36, 36 ', 47, 51) are designed as electric stepper motors, which are connected via control lines with a control device (60).

22. Device according to one of claims 8 to 21, characterized in that at least some of the mentioned

Actuators (32, 33, 34, 36, 36 ', 47, 51) are designed as fluid-operated actuators whose control valves are connected via control lines to a control device.