METHOD FOR WINDING A WIRE ABOUT A TOOTHED PART OF AN ELECTRIC MOTOR

Abstract

A method and an apparatus for providing a toothed motor part of an electric motor with a winding using a coil wire with a round wire cross-section, wherein the coil wire is converted into a coil wire with a wire cross-section different from the round wire cross-section in a forming process, and the formed coil wire is wound around the teeth of the motor part to produce a rotating field winding.

Claims

1. A method for providing a toothed motor part of an electric motor with a winding using a coil wire with a round wire cross-section, the method comprising: converting the coil wire into a coil wire with a wire cross-section different from the round wire cross-section in a forming process; and wounding the formed coil wire around teeth of the motor part to produce a rotating field winding.

2. The method according to claim 1, wherein a cross-sectional shape of the formed coil wire is varied during a course of producing the rotating field winding.

3. The method according to claim 1, wherein one or more angles of inclination between the lateral faces of the wire cross-section of the formed coil wire is or are varied during the course of producing the rotating field winding.

4. A method for providing a toothed motor part of an electric motor with a winding using a coil wire with a round wire cross-section, the method comprising: converting the coil wire into a coil wire with a rectangular wire cross-section in a forming process; wounding the formed coil wire around teeth of the motor part to produce a rotating field winding; varying a shape of the rectangular wire cross-section of the formed coil wire during a course of producing the rotating field winding; and varying one or more angles of inclination between the lateral faces of the rectangular wire cross-section of the formed coil wire during the course of producing the rotating field winding.

5. The method according to claim 1, wherein the formed coil wire is wound on a bobbin surrounding the applicable tooth.

6. The method according to claim 1, wherein the coil wire is rolled during the forming process.

7. An apparatus for carrying out the method according to claim 1, the apparatus comprising: a winding device for providing the motor part with a winding; a spool for supplying the winding device with the coil wire; a forming device arranged between the spool and the winding device for converting the cross-sectional shape of the coil wire from a round wire cross-section into a rectangular cross-section or into a wire cross-section that differs from the round wire cross-section; and a controller for controlling the forming device.

8. The apparatus according to claim 7, wherein the forming device has a number of rollers arranged one behind the other in the feed direction of the coil wire to the winding device.

9. The apparatus according to claim 8, wherein the rollers are adjusted or adjustable in a pivot angle relative to one another.

10. The apparatus according to claim 7, wherein the winding device is a coil winding tool or single segment winding tool.

11. The apparatus according to claim 7, wherein the forming device drives the rollers and presses the coil wire through the rollers.

12. A stator for an electric motor, provided with a winding in accordance with the method according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0032] FIG. 1 is in schematic representation, an apparatus for winding a stator with a coil wire, having a spool and having a forming device and also having a winding tool;

[0033] FIG. 2 is in a top view, a cross-sectional representation of a wound stator tooth with a bobbin with a single-layer coil winding;

[0034] FIG. 3 is in a top view, a cross-sectional representation of the wound stator tooth with the bobbin with a multilayer coil winding;

[0035] FIG. 4 is in a perspective representation, the coil wire with a round wire cross-section;

[0036] FIG. 5 is in a perspective representation, a formed coil wire with a rectangular wire cross-section;

[0037] FIG. 6 is in a perspective representation, a formed coil wire with a trapezoidal wire cross-section;

[0038] FIG. 7 is in a top view, a cross-sectional representation of a wound bobbin with a single-layer coil winding with an oval wire cross-section; and

[0039] FIG. 8 is in a top view, a cross-sectional representation of a wound bobbin with a multilayer coil winding with an oval wire cross-section.

DETAILED DESCRIPTION

[0040] In FIG. 1, an apparatus 2 for providing a toothed motor part 4, in particular a stator 4, with a winding is shown in a schematic and highly simplified representation. The apparatus 2 is suitable and equipped to wind the (stator) teeth 6 of the stator 4 with a coil wire 8 to produce a rotating field winding.

[0041] The apparatus 2 includes a spool 10, on which coil wire 8 is supported in a coiled manner. At one free end, the coil wire 8 is carried along a feed direction 12 to a forming device 14. Downstream of the forming device 14, following essentially without interruption, is a winding device 16, with which the formed coil wire 8 is wound on the teeth 6 of the stator 4.

[0042] The stator 4 is composed substantially of a stator core 4a and a yoke core 4b, which in the assembled state essentially forms an annulus-like laminated core with a number of inwardly directed teeth 6 arranged in a star shape.

[0043] As can be seen in FIGS. 2 and 3, a tubular bobbin 18, which encloses the associated tooth 6, is arranged preferably on each of the teeth 6 of the stator 4. The bobbins 18 are preferably made of an electrically insulating material as an injection-molded part. In the assembled state, the bobbins 18 are arranged around the teeth 6, and they each havewith reference to the central recess of the stator 4an interior flange collar 18a and an exterior flange collar 18b as the delimitation of the applicable winding space.

[0044] The star core 4a is essentially composed of a number of separate teeth or toothed segments 6. The bobbins 18 are placed on the toothed segments 6 and are individually wound with the coil wire 8 by the winding device 16, which is implemented as a single segment winder, in particular. Alternatively, the bobbins 18 are first wound, and are then placed on the toothed segments 6. After the winding of the coil thus created, the coil wire 8 is cut to length. After the assembly of the stator 4, the coil ends thus created of the individual coils are connected, for example by means of an installation ring, to form a common rotating field winding.

[0045] As can be seen especially well in FIG. 2 and FIG. 3, the toothed segments 6 have, on the yoke side, an approximately roof-shaped joint contour 19a, which is inserted in a corresponding joint seat 19b of the yoke core 4b upon insertion in the yoke core 4b. The joint contour 19a and joint seat 19b are only indicated with dashed lines in FIG. 2 and FIG. 3 here.

[0046] To prevent a tangential tilting of the applicable tooth 6, the inside perimeter of the yoke core 4b has a polygonal cross-section, in particular. In useful fashion, the inside perimeter of the yoke core 4b in this case has a number of inner edges formed thereby corresponding to the number of teeth 6, wherein each straight inner edge has a joint seat 19b in the center. As becomes relatively clear in FIGS. 2 and 3, the flange collar 18b of the bobbin 18 on the outer perimeter side rests over essentially its entire width on such an inner edge of the yoke core 4b so that the tooth 6 is secured against tilting.

[0047] The joining of the stator 4, formed of the star core 4a composed of individual toothed segments 6 and the yoke core 4b, by means of the joint contours 19a and joint seats 19b, and in particular the securing against tilting by means of the bobbin 18, are considered an independent invention.

[0048] The coil wire 8 is implemented as an insulated wire with an electrically conductive conductor 20, and with insulation 22 jacketing the same. The conductor 20 is preferably made of an easily deformable copper material that is coated with an electrically insulating varnish as insulation 22. The coil wire 8 is, in particular, a round wire, which means that the coil wire 8 hasas is shown in FIG. 4a substantially circular wire cross-section.

[0049] In operation of the apparatus 2, the coil wire 8 is reeled off of the spool 10 and conveyed in the feed direction 12 to the forming device 14. The forming device 14 has two pairs of rollers 24 oriented substantially perpendicular to one another, with which the coil wire 8 is formed from a round wire cross-section into a wire cross-section that differs from round, in particular in this exemplary embodiment, into a substantially rectangular wire cross-section. The rollers 24a, 24b, which are arranged in pairs, are staggered and arranged one behind the other with respect to the feed direction 12 so that the coil wire 8 is formed incrementally, in particular. The roller pairs 24 are connected to a common controller 26 as the control unit.

[0050] The coil wire 8 is usefully passed through, in particular pressed through, between the rollers 24a, 24b of the applicable roller pair 24, so that the coil wire 8 is rolled between the rollers 24a, 24b. The coil wire 8 can be converted into a rectangular wire cross-sectionas is shown by way of example in FIG. 5by the roller pairs 24. The coil wire 8, which consequently is formed somewhat in the manner of a flat wire, is then fed to the winding device 16. The winding device 16 winds the coil wire 8 on the teeth 6 or the bobbins 18 in order to produce the rotating field winding.

[0051] The controller 26 is suitable and equipped to drive the roller pairs 24 during the course of producing the rotating field winding in such a manner that the shape of the wire cross-section of the formed coil wire 8 is varied. This means that the controller 26 causes an appropriate control signal that moves the rollers 24a, 24b of the applicable roller pair 24 toward one another or away from one another, by which means the height-to-width ratio of the, e.g., rectangular wire cross-section is changed. In other words, over the course of the rotating field winding, the coil wire 8 has a wire cross-section with a number of different shapes that transition integrally into one another and in which the wire cross-sectional area that is enclosed in each case remains substantially the same. This is indicated by way of example in FIG. 2 and FIG. 3, wherein the coil wire 8 is formed to be increasingly flatter toward the outer circumference of the stator 4. In this way, an especially high fill factor is realized in the winding space between the flange collars 18a and 18b.

[0052] In an additional or alternative embodiment, the roller pairs 24, or the individual rollers 24a, 24b of the roller pairs 24, are designed to be pivotable toward or with respect to one another. In this way, it is possible to vary one or more angles of inclination 28, 30 between the lateral faces of the formed coil wire 8 during the forming. In this way, the coil wire 8 can be formed into a coil wire 8 with a trapezoidal wire cross-section shown in FIG. 6, for example.

[0053] Shown as details in FIG. 7 and in FIG. 8 are two additional bobbins 18, on each of which is wound a coil wire 8. FIGS. 7 and 8 each show a variable cross-sectional shape of the coil wire 8 during the course of the coil winding or rotating field winding.

[0054] The upright or radially varying coil winding in FIG. 7 is essentially identical to the winding from FIG. 2, although the coil wire 8 in FIG. 7 is not quadrangular rolled into a rectangular wire cross-section. The coil wire 8 in the exemplary embodiments from FIG. 7 and FIG. 8 is merely rolled flat on two sides from the round wire cross-section so that the narrow sides or lateral edges are approximately semicircular in design. In other words, the coil wire 8 is rolled on two diametrically opposed faces or longitudinal sides for forming.

[0055] The exemplary embodiment from FIG. 8 here shows a coil winding of the bobbin 18 in which the coil wire 8 is wound flat. In other words, the wire cross-section essentially is not varied for sequential (coil) windings, but rather for sequential coil layers or coil courses. This means that, proceeding from the bobbin carrier 18 [sic; presumably should say bobbin 18], the wire cross-section is varied in the transverse direction, which is to say in the tangential or circumferential direction in the assembled state.

[0056] The invention is not limited to the exemplary embodiments described above. Instead, other variants of the invention can also be derived therefrom by the person skilled in the art without departing from the subject matter of the invention. In particular, moreover, all individual features described in connection with the exemplary embodiments may also be combined with one another in other ways without departing from the subject matter of the invention.

[0057] Thus it is also possible, for example, to form the coil wire 8 into a polygonal, in particular triangular or hexagonal, wire cross-section. The essential point is that the cross-sectional geometry is designed to be variable within one coil or rotating field winding. In particular, the winding start and the winding end, which means the coil or phase ends, are implemented as non-formed round wire 8, wherein the windings or turns are wound with the formed flat or shaped wire 8, in particular. In particular, it is possible here that each turn of a coil has an individual and different wire cross-section from the adjacent turns.

[0058] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.