WO2012089404A2

WO2012089404A2 - Winding tooth for an electric machine, machine component and electric machine

Info

Publication number: WO2012089404A2
Application number: PCT/EP2011/070354
Authority: WO
Inventors: Torsten Wilharm; Tilo Koenig; Maxim Sukhman
Original assignee: Robert Bosch Gmbh
Priority date: 2010-12-27
Filing date: 2011-11-17
Publication date: 2012-07-05
Also published as: WO2012089404A3; DE102010064173A1

Abstract

The invention relates to a winding tooth (3) for an electric machine with a tooth stem (4) and a tooth tip (5), which is arranged at one end of the tooth stem (4) with respect to a direction of extent (E) of the tooth stem (4) and which protrudes beyond the tooth stem (4) in a tooth tip direction (U) perpendicular to the direction of extent (E), wherein the tooth tip (5) is tapered at at least one end with respect to a transversal direction (Z), which runs perpendicular to the direction of extent (E) and perpendicular to the tooth tip direction (U), in which the tooth tip (5) protrudes.

Description

description

title

Winding tooth for an electrical machine, machine component and electric machine

Technical area

The present invention relates generally to electrical machines, particularly electrical machines having machine components constructed by stacking laminations. Furthermore, the present invention relates to the improvement of the Wrkungsgrades and the improvement of the thermal contact resistance and reduction of the installation space in electrical machines.

State of the art

Machine components, such as stators or rotor of electrical machines, are often built in lamellar construction of lamella plates. The lamellar plates are usually similarly punched and stacked on top of each other, so that these - in rotary electric machines in the axial direction, otherwise generally in a direction perpendicular to a relative direction of movement between the stator and rotor - lie on each other. The laminations are typically insulated from each other to reduce the flow of wrinkles in the machine component.

Depending on the type of electric machine, the machine component has winding teeth which protrude either inward or outward in a radial direction from a carrier element which forms a magnetic return, and from a tooth head which is wider in the relative direction of movement than the toothed shaft. be completed. The winding teeth are often isolated before winding by means of insulating parts in the form of plastic masks, paper, powder or paint or a combination thereof and then wound with winding wire, such as a copper wire. This insulation of the winding teeth serves the mechanical protection of usually only with a thin lacquer layer isolated Waklungsdrahtes in front of the sharp-edged plate edges.

The machine component can either be made in one piece from a plurality of similar stacked individual lamella plates, which is usually referred to as a complete section, or multiple parts, which is usually referred to as a split section or split stator or multi-part section or multi-part stator. Regardless of the construction and the insulation of the winding teeth, the geometry of the sheet metal section of the individual laminations is often identical, to require only a single punching tool or a punching tool of low complexity.

From the document DE 10/2004 018208 A1 a winding carrier for an electrical machine is known which is designed as a laminated core and has a plurality of pole teeth (winding teeth). The winding teeth each have a toothed base with Polfußfuß (tooth tip), around which the Wcklung can be arranged. The tooth shanks of the toothing teeth are designed so that they have a variable width starting from the end faces of the laminated core.

Such a design leads to a better use of the available space, but does not represent the optimum, depending on the geometric conditions alone. This is particularly the case when the angle between the tooth and tooth tip is deviating from 90 °.

It is therefore an object of the present invention to provide a toothing tooth and a machine component for an electrical machine, by means of which an improved winding is made possible and in particular an improvement in the thermal contact resistances of the wound machine component is achieved. Disclosure of the invention

This object is achieved by the winding tooth for an electric machine according to claim 1 and by the machine component and the electric machine according to the independent claims.

Further advantageous embodiments are specified in the dependent claims.

According to a first aspect, there is provided an inverting tooth for an electric machine having a tooth shaft and a tooth tip disposed at one end of the tooth shaft with respect to an extension direction of the tooth shaft and projecting beyond the tooth shaft in a tooth head direction perpendicular to the extension direction. The tooth tip is tapered at at least one end with respect to a transverse direction that is perpendicular to the extension direction and perpendicular to the tooth tip direction in which the tooth tip protrudes.

An idea of the above invention is to reduce the width of the tooth tips with respect to the direction of extension direction of the tooth shaft toward an end of the tooth for toothing with respect to the transverse direction. As a result, the tooth cross-section in the area of the toothed shaft is virtually rounded and thus the circumference reduced, which results in winding in a reduced wire length and thus in lower ohmic losses, increased efficiency and lower material costs. The grading of the tooth heads makes better use of the available space and improves the thermal contact resistance.

Furthermore, the toothing tooth may comprise a stack of laminations stacked in the transverse direction, wherein a first lamination is provided with a first geometry and a second lamination with a second geometry, wherein the first geometry provides a width of the tooth head in the extension direction, which is larger as the width of the tooth head in the extension direction in the second geometry to provide a gradation of the tooth head, in particular, the second lamination corresponds to a last lamination of the stack of laminations .. In other words, the second corresponds Sheet metal of the second geometry of a lamination, which forms a conclusion of the stack.

According to one embodiment, the toothed shaft may be tapered at at least one end, with respect to a transverse direction that is perpendicular to the extension direction and perpendicular to the tooth tip direction.

It can be provided that the first lamination with the first geometry provides a width of the toothed shaft transversely to the extension direction, which is greater in the tooth-head direction than the corresponding width of the toothed shaft in the second geometry.

According to a further aspect, a machine component, in particular a stator or rotor of an electrical machine, is provided with one or more of the above winding teeth.

According to one embodiment, the machine component may be composed of a plurality of similar segments each having one or more winding teeth.

According to a further aspect, a machine component, in particular a stator or rotor of an electrical machine, is provided with one or more of the above teeth, wherein at least one of the winding teeth is provided with an insulating part which is shaped to be one or both of the tapered ones Ends of the tooth shaft covered. The optimized design of the insulating parts, which can be placed on the tapered end of the toothed shaft, allows reliable protection of the winding wire with a small cross-sectional area. The insulating part may be formed as a separate component or by encapsulation of the winding teeth with an insulating material.

According to another aspect, there is provided an engine component for an electric machine having a tooth for toothing with a toothed shaft and a stator portion, the toothed shaft being disposed at one end with respect to its extending direction at the stator portion, the stator portion being in a stator direction perpendicular to the extending direction of the tooth - Stem projects, wherein the stator section is tapered at at least one end with respect to a transverse direction which is perpendicular to the extension direction and perpendicular to the stator direction, tapered.

Furthermore, the winding tooth may have a tooth tip, which is arranged at a further end of the tooth shaft with respect to an extension direction of the tooth shaft and which protrudes in a tooth head direction corresponding to the stator direction, perpendicular to the extension direction over the tooth shaft, wherein the tooth tip at least an end is tapered with respect to the transverse direction.

According to one embodiment, the toothed shaft may be tapered at at least one end with respect to the transverse direction.

It can be provided that the winding tooth has a stack of laminations, which are stacked in the transverse direction, wherein a first laminations are provided with a first geometry and a second laminations with a second geometry, wherein the first laminations with the first geometry has a width of Tooth sprocket transversely to its extension direction provides, which is greater than the corresponding width of the toothed shaft in the second geometry with respect to the tooth head direction in which the tooth head protrudes beyond the toothed shaft.

It may be provided that the winding teeth are wound with sprocket wire to form a wadlung.

In another aspect, an electric machine with the above machine component is provided.

Brief description of the drawings

Preferred embodiments of the present invention will be explained in more detail with reference to the accompanying drawings. Show it: FIGS. 1a-1c show various laminations for constructing a stator of an internal rotor motor in one-part or multi-part design;

FIG. 2 is a perspective view of the sheet metal section or

Plate packs of a stator according to an embodiment of the present invention;

Figure 3 is a sectional view of a stator tooth of the stator according to an embodiment of the present invention; and

Figure 4 shows a cross section through a wound toothed shaft

Placing an insulating part on the stator tooth of Figures 2 and 3.

Description of embodiments

FIGS. 1 a to 1 c show different geometries of laminations for laminations for constructing a stator for an electrical machine. The stator is built up by stacking the lamella plates. The stator of the electric machine to be produced should have stator teeth to be wound with winding wire to make a stator winding.

The geometry shown in FIG. 1 a shows a lamination plate 20, which images the cross section of the complete stator cross-section in one piece as a complete section. Such a sheet metal section is suitable for the production of small and large size electrical machines. The fin plate 20 has a stator yoke plate portion 21, a toothed plate portion 22, and a tooth tip portion 23 each provided for forming a stator yoke, a tooth stem, and a tooth tip, respectively, of a stator constructed of stacked laminations. Such lamella plates are punched or cut by laser cutting, and then stacked on each other, so that the individual lamellae are congruent to each other. As a result, the stator is formed with stator teeth which have a cross-section perpendicular to their longitudinal extent in the winding plane of a stator winding to be applied thereon, which extends in the axial direction (stacking direction). According to other possibilities, a stator may also be constructed from lamination plates which form a stator section when stacked. The stator sections can then be assembled into a stator. In FIG. 1 b, for example, the stator yoke and the stator teeth located in the interior of the stator yoke are made up of separate lamination plates.

In Figure 1 c, the disk set of the stator is constructed of laminations, each forming the same stator segments for the construction of a stator. The like segments have approximately the structure of a double T and are circumferentially butted together to form a cylindrical stator. Each of the stator segments carries one or more of the stator teeth forming sheet metal areas. FIG. 2 is a perspective view of a disk set 1 for constructing an electrical machine, such as a synchronous machine or the like. The illustrated disk set 1 is provided for an internal rotor motor and therefore has an internal recess. The stator 1 comprises a stator yoke 2, from which stator teeth 3 protrude radially into the interior of the cylindrical stator yoke 2. Each of the stator teeth 3 has a tooth shank 4 and a tooth tip 5 arranged at the inward end of the stator tooth 3. The tooth head 5 has an outer contour 7 directed into the interior of the stator 1 or onto a rotor, which defines the region in which the rotor (not shown) of the electric machine to be formed with the stator 1 is arranged. The type of outer contour of the tooth heads is used to define the shape of the air gap between the rotor poles of the rotor and the tooth tips 5. The outer contour of the tooth tips is opposite to a bottom 6 of the tooth head 5, which faces the tooth shaft 4. The underside 6 closes with an extension direction E of the tooth shank, i. with an extending in the radial direction side or center axis of the toothed shaft 4 an obtuse angle. In other words, the underside 6 extends obliquely to the respective extension direction E of the extension of the toothed shaft 4 and obliquely to one

Tooth-head direction U, which in rotating electrical machines of a Um- catch direction or a tangential direction corresponds. The tooth-head direction U generally corresponds to the direction in which electrical movement takes place between the stator and the rotor.

To build an electric machine, the stator teeth 3 of the stator 1 are wound with winding wire to produce a stator winding. In order to reduce the wire length of the sprocket wire, the thickness of the tooth shank 4 in the tooth-head direction U at the ends of the stator teeth 3 in an axial direction, that is, in an axial direction. in a transverse direction Z, which is perpendicular to the respective extension direction E of the toothed shaft 4 and substantially perpendicular to the tooth head direction U of the corresponding tooth head 5, tapers, so that the cross section of the tooth shaft 4 approaches a rounding there. In practice, this is achieved by laminating laminations of different geometries to one another, wherein a stack of laminations forming an inner region (in the transverse direction) of the stator 1, for. As those, as shown in Figures 1 a to 1 c, further lamella plates are stacked with Zahnschaftblechbereichen reduced width in the direction of the tooth head. Tooth shafts 4 of the stator teeth 3 are thereby formed, which taper in a stepwise manner to the ends of the stator in the transverse direction Z out.

When winding the toothed shaft 4 with winding wire, the wire length required for the winding can thereby be reduced, so that the ohmic resistance of the winding is reduced. This manifests itself in an increased degree of wrinkling of the electrical machine and lower material costs for the winding wire.

In particular, at the end of the washer facing the tooth head 5, because of the obliquely running underside 6 of the tooth head 5, it can happen that walls of the washer are pressed against the side facing the tooth head 5. This can cause the stator winding to thicken in this area. To counteract this effect, it is provided that the width of the tooth head 5 tapers towards at least one of the ends of the stator teeth 3 in the transverse direction Z (axial direction). Since the rotor facing the outer contour of the tooth head 5 defines the air gap and should substantially correspond to a lateral surface of a circular cylinder, the taper takes place on the underside 6 of the tooth head 5, which faces the toothed shaft 4. Furthermore, it can be provided that the stator 1 in a stator section, on which the toothed shaft 4 protrudes from the stator yoke 2, has a toothing 5 corresponding to the taper. In other words, a side of the stator 2 facing the toothed shaft 4 is tapered in the transverse direction Z in the region of the section on which the toothed shaft 4 is connected to the stator 2. As a result, as described above in connection with the tooth head 5, the effect of urging the turns of the windings against the side facing the stator yoke 2 can be counteracted.

FIG. 3 shows a detailed illustration of one of the stator teeth 3 in a section. The stator tooth 3, which is shown by way of example in FIG. 3, has two steps at an axial end of the toothed shaft 4, which reduce the thickness of the toothed shaft 4 in the circumferential direction. 3. It can be seen that not only the toothed shaft 4 but also the thickness of the tooth head 5 tapers towards the axial end of the stator tooth 3, in that the toothed shaft 4 is tapered facing bottom 6 of the tooth head 5 is displaced in the direction of the outer contour 7 of the tooth head 5.

Furthermore, the Wcklungsdrahtquerschnitte are indicated in Figure 3. It can be seen windings 8, which are wound in several layers around the toothed shaft 4. One or more further turns 9 are provided for exploiting the available winding space in a region 10 which is formed by the space between a perpendicular to the extension of the toothed shaft 4 in the circumferential direction (tooth head direction) and the underside 6 of the tooth head 5. In the case of a non-tapering tooth head 5, this would mean that these further turns 9 would have been forced into a transitional area 11 in which the toothed shaft 4 merges into the tooth head 5, and thus the thickness of the stator winding where it is in the transition area 1 1 is applied to the tooth head 5, would increase. This limits the number of turns and thereby reduces the groove fill factor between adjacent stator teeth 3. The taper of the tooth tip 5 gives the further turns 9 sufficient space so that the stator winding does not widen overall at its end. FIG. 4 shows a cross section through the toothed shaft 4 with the windings 8 of the stator winding wound around it. In order for the winding wire, which is surrounded by an insulating varnish, not to be damaged at the edges of the steps of the tapered toothed shaft 4, an insulating mask 12 is provided which has an inner contour 13 which substantially corresponds to the contour of the tapering toothed shaft 4 that the insulating mask 12 can be placed on the axial end of the toothed shaft 4.

Furthermore, the insulating mask 12 has an outer contour 14 which is curved and preferably in no section has a curvature which is greater than a predetermined threshold value. Preferably, the outer contour of the insulating mask 12 is semicircular, so that the walls 9 of the stator winding can rest against the outer contour 14. The insulating mask 12 is preferably formed in two parts, wherein the two parts of the insulating mask 12 are placed on both sides of the toothed shaft 4. For example, identical or nearly identical insulating masks 12 can be placed on both sides of the toothed shaft 4.

As a rule, the cross section of the tooth tips 5 is determined by the design of the magnetic circuit in the electrical machine. Often, the cross-section of the tooth heads 5 is oversized due to the mechanical strength and the manufacturability of the laminations and the building on him insulating masks. By grading the tooth heads 5 of the available space can be used better.

Furthermore, the width of the insulating mask 12 is determined by the tooth tips 5 in the widest region with respect to the tooth head direction U (perpendicular to the axial direction and in the direction of relative movement between the stator and the rotor), if the design is based on harmonic tangential transitions of the surfaces without stiffening. is aligned. This is necessary for a good manufacturability of the insulating masks and a good wire position of the winding wire. Due to the stepped design of the tooth cross-sections, the insulating masks 12 shift relative to one another and the axially last tooth head plates would lead to a very small wall thickness of the insulating masks 12 or the insulating masks 12 would have to be greatly oversized in the remaining region. Therefore it is also from this

Reason advantageous to scale the tooth head 5 similar to the tooth shaft 4. It can be provided to also taper the stator yoke at the end opposite the tooth tip of the tooth shaft. The taper has advantages in the manufacture of the stator, particularly in the application of the insulating mask 12. The gradient of the taper may or may not be different from the gradient of the taper of the tooth tip.

Claims

claims

A winding tooth (3) for an electric machine having a toothed shaft (4) and a tooth head (5) disposed at one end of the tooth shank (4) with respect to an extension direction (E) of the tooth shank (4) and in a tooth tip Direction (U) perpendicular to the extension direction (E) beyond the toothed shaft (4),

wherein the tooth tip (5) is tapered at at least one end with respect to a transverse direction (Z) perpendicular to the extending direction (E) and perpendicular to the tooth tip direction (U) in which the tooth tip (5) protrudes.

2. winding tooth according to claim 1, wherein the Weckzahn (3) comprises a stack of laminations, which are stacked in the transverse direction (Z), wherein a first lamination with a first geometry and a second lamination are provided with a second geometry, wherein the first Geometry a width of the tooth head (5) in the extension direction (E) provides that is greater than the width of the tooth head (5) in the extension direction (E) in the second geometry to provide a grading of the tooth head (5), wherein the second lamination in particular corresponds to a last lamination of the stack of laminations.

3. winding tooth according to claim 1 or 2, wherein the toothed shaft (4) at at least one end with respect to the transverse direction (Z) which is perpendicular to the extension direction (E) and perpendicular to the tooth tip direction (U), tapers.

4. winding tooth according to claim 3, wherein the winding tooth (3) comprises a stack of laminations, which are stacked in the transverse direction (Z), wherein a first lamination with a first geometry and a second lamination are provided with a second geometry, wherein the first Lamination with the first geometry a width of the toothed shaft (4) across to its extension means (E) provides that with respect to the tooth head direction (U), in which the tooth head (5) over the toothed shaft (4) protrudes, is greater than the corresponding width of the toothed shaft (4) in the second lamination of the second geometry ,

Machine component, in particular stator or rotor of an electrical machine, with one or more winding teeth (3) according to one of claims 1 to 4.

Machine component, in particular stator or rotor of an electrical machine, having one or more winding teeth (3) according to one of Claims 3 and 4, at least one of the dressing teeth (3) being provided with an insulating part (12) which is shaped in such a way one or both of the tapered ends of the toothed shaft (4) covered.

A machine component for an electric machine having a toothed tooth (3) with a toothed shaft (4) and a stator section, wherein the toothed shaft (4) is arranged with one end with respect to its extension (E) on the stator section, the stator section being arranged in a stator Direction (U) perpendicular to the extension (E) of the toothed shaft (4),

wherein the stator section is tapered at at least one end with respect to a transverse direction (Z) that is perpendicular to the extension direction (E) and perpendicular to the stator direction.

A machine component according to claim 7, wherein the toothing tooth (3) has a tooth tip (5) disposed at a further end of the tooth shank (4) with respect to an extension (E) of the tooth shank (4) and which is in a tooth tip direction (U ), which corresponds to the stator direction, projects perpendicular to the extension means (E) beyond the toothed shaft (4),

wherein the tooth tip (5) is tapered at at least one end with respect to the transverse direction (Z).

9. A machine component according to claim 8, wherein the toothed shaft (4) is tapered at at least one end with respect to the transverse direction (Z).

10. Machine component according to one of claims 7 to 9, wherein the winding tooth (3) comprises a stack of laminations, which are stacked in the transverse direction (Z), wherein a first lamination with a first geometry and a second lamination are provided with a second geometry wherein the first lamination of the first geometry provides a width of the tooth shank (4) transversely to its direction of extent (E) which protrudes beyond the tooth shank (4) with respect to the tooth head direction (U) in which the tooth head (5) projects is greater than the corresponding width of the toothed shaft (4) in the second geometry.

1 1. A machine component according to any one of claims 5 to 10, wherein the winding teeth (3) are wound with winding wire, which forms a winding.

12. Machine component according to one of claims 5 to 1 1, wherein the machine component of a plurality of similar segments each having one or more winding teeth (3) is composed.

13. Electrical machine with a machine component according to one of claims 5 to 12.