Stator with a support web between a stator tooth and the corresponding coil, and axial flux machine
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-05-14
- Publication Date
- 2026-04-08
AI Technical Summary
Existing stators in axial and radial flux machines face challenges with coolant gap tolerances, leading to high flow resistance due to uneven support of windings, which results in manufacturing tolerances that are difficult to maintain, affecting cooling efficiency.
The stator design incorporates support webs along the radially outer and inner edges of stator teeth to ensure consistent winding support, creating predefined coolant channels that enhance cooling efficiency by maintaining precise distances between windings and stator teeth, allowing for effective coolant flow and distribution.
This design reduces manufacturing tolerances and improves thermal management by ensuring consistent coolant flow and distribution, enhancing the cooling efficiency of stator windings and maintaining effective thermal resistance.
Smart Images
Figure DE2024100442_28112024_PF_FP_ABST
Abstract
Description
[0001] Stator with a support steq between stator tooth and associated winding and axial flux machine
[0002] The present disclosure relates to a stator having a plurality of adjacent stator teeth, wherein at least one stator tooth is completely wound by a winding, and the winding has at least one inner winding layer that directly surrounds the stator tooth, and wherein the winding has a plurality of turns arranged one above the other, viewed in the longitudinal direction of the stator tooth. The present disclosure further relates to an axial flux machine.
[0003] Corresponding stators are regularly used in an axial flux machine, particularly in an I-configuration. An axial flux machine is a disk-shaped electrical machine and has a preferably (circular) disk-shaped rotor surrounded by two, preferably ring-shaped stators. An air gap is provided between each stator and the rotor. The stator teeth are arranged in a ring-shaped manner as a circumferential ring and are integrally connected to one another. Between adjacent stator teeth, a winding slot is provided to accommodate the sections of adjacent windings extending in the radial direction (in an axial flux machine) (in the axial direction in a radial flux machine). A yoke (which is not present in axial flux machines in an H-arrangement), which magnetically connects the stator teeth, and the stator teeth together form a stator core. The yoke is mainly located on the back of the stator teeth, i.e.Arranged on a side of the stator facing away from the rotor (and running along the outer circumference of the stator teeth). The corresponding winding extends along the outer circumference of each stator tooth. The windings of the stator teeth of the stators change polarity, setting permanent magnets attached to the rotor in motion, causing the axial flux machine to rotate about its axis of rotation. Alternatively, corresponding stators can be used in a radial flux machine.
[0004] The directions of the stator (of an axial flux machine and a radial flux machine) are based on the orientation of the rotation axis: the axial direction of the stator runs along the rotation axis, the radial direction of the stator runs perpendicular to the rotation axis, and the circumferential direction corresponds to the direction of rotation of the stator around the rotation axis. In an axial flux machine, the longitudinal direction of the stator teeth extends in the axial direction of the stator. In a radial flux machine, the longitudinal direction of the stator teeth extends in the radial direction of the stator. In other words, the longitudinal direction of the stator teeth in both axial flux machines and radial flux machines extends in the direction of the air gap between the rotor and stator.
[0005] The stator core preferably consists of electrical steel sheet wound in a ring shape in the circumferential direction, which thus forms multiple layers in the radial direction. The stator core is manufactured, for example, using the punch-winding process, which is disclosed, for example, in EP 2 787 610 B1. In this process, a strip-shaped raw material, which forms the electrical steel sheet, is fed to a system. Before the electrical steel sheet is fed to the system, cutouts are punched into the initially strip-shaped electrical steel sheet using a tool. The electrical steel sheet is then wound in the system to form an annular stator core. The cutouts previously introduced into the electrical steel sheet form winding slots for accommodating windings when wound. Accordingly, each stator tooth is laterally surrounded by two winding slots. The winding slots extend in the radial direction.The winding slots (in an axial flux machine), together with the radially outer and inner edges of the respective stator tooth, define the circumference of the stator tooth. A winding corresponding to the stator tooth extends along the entire circumference of each stator tooth.
[0006] Typically, each winding surrounding a corresponding stator tooth has an inner winding layer located in close proximity to the respective stator tooth and an outer winding layer adjacent to the outer circumference of the inner winding layer. Typically, both the inner winding layer and the outer winding layer of the winding of each stator tooth have a plurality of turns or winding layers arranged one behind the other in the longitudinal direction of the stator teeth, or in the axial direction of the stator in an axial flux machine. All sections of the turns extending in the radial direction are spaced (in the circumferential direction) from the corresponding stator tooth. These spacings define a gap between the stator tooth and the inner winding layer that is continuous in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine).The continuous gap between the inner winding layer and the corresponding stator tooth forms a stator tooth-winding coolant channel. Single-layer windings are also available, which are then designed like the inner winding layer. In this case, the turns of the inner winding layer (as well as those of the outer winding layer) are aligned with each other across the entire winding, viewed in the longitudinal direction of the stator tooth (in the axial direction for axial flux machines).
[0007] Additionally or alternatively, a circumferential clearance is provided between each turn (of the outer winding layer) of the winding of a stator tooth and each turn (of the outer winding layer) of the winding of an adjacent stator tooth. These clearances also define a continuous gap in the longitudinal direction of the stator teeth (in the axial direction for axial flux machines) between the (outer winding layers of) the windings of two adjacent stator teeth. The continuous gap between the (outer winding layers of) the windings of two adjacent stator teeth forms an interwinding cooling channel.
[0008] The coolant channels ensure that all windings exhibit low thermal resistance to the coolant. The combination of the stator tooth winding coolant channel with the interwinding cooling channel offers advantages for efficient cooling not only for multi-layer windings, i.e., windings with inner and outer winding layers, but also for single-layer windings.
[0009] In other words, in axial-flux machines or radial-flux machines, so-called single-tooth windings (windings each wound around a stator tooth) are directly surrounded by liquid cooling. The single-tooth windings are typically designed in two layers (each with an inner and outer winding layer). To ensure that each winding layer has direct coolant contact, there are two additional coolant gaps in addition to the coolant gap between adjacent windings. These additional coolant gaps are located between the windings and the stator tooth around which they are wound. For example, EP 3 108 574 B1 and EP 3 764 526 A1 each disclose a stator in which a coolant gap is provided between the windings of adjacent stator teeth.In addition, spacers are provided between each stator tooth and the corresponding winding, which ensure the distance between the winding and the stator tooth at specific points along the entire circumference of the stator tooth. Adhesive dots are often used as spacers.
[0010] However, the spacers only ensure the distance between the stator tooth and the associated winding at specific points, so that only individual turns of the respective winding are supported. Support is provided both in the area of the winding slots and in the area of the winding overhangs (sections of the windings that extend in the circumferential direction). Neighboring windings are only indirectly supported (via the directly supported windings). Due to tolerances and elasticity between the windings, the resulting coolant gap or distance between the stator tooth and the associated winding is subject to significant tolerances.
[0011] However, due to the strong dependence of the flow resistance on the width of the coolant gap or the distance between the stator tooth and the associated winding (which is clearly disproportionate), close tolerances for the distance between the stator tooth and the associated winding, i.e. for the width of the coolant gap, should be maintained.
[0012] Against this background, the present disclosure aims to provide a stator that mitigates or eliminates the disadvantages of the prior art. In particular, a stator or an axial flux machine with a corresponding stator is to be provided that has coolant gaps / coolant channels, particularly on the circumferentially extending portions of the stator teeth, for directly cooling stator teeth that are subject to only small manufacturing tolerances.
[0013] This object is achieved by the subject matter having the features of the independent patent claim and by the subject matter having the features of the independent patent claim. Advantageous embodiments are the subject matter of the dependent claims. The stator according to independent patent claim 1 has a plurality of mutually adjacent stator teeth. In particular, the stator is intended to be used in an axial flux machine, but can alternatively be used in a radial flux machine. The entire circumference of at least one stator tooth, preferably each stator tooth, is / at least one, in particular each, stator tooth is completely wound by (each) a (single-tooth) winding. Preferably, the sections of the windings of adjacent stator teeth extending in the radial direction (in an axial flux machine) (in the axial direction in a radial flux machine) face one another.In particular, the stator has a yoke / lamination stack that magnetically and preferably mechanically connects the stator teeth to one another. The yoke is preferably arranged on a side of the stator facing away from the rotor and, in particular, conceals the rear side and also a circumferentially extending section of the stator teeth. Each winding has at least one inner winding layer that is arranged in the immediate vicinity of the respective stator tooth, or in other words, directly surrounds the stator, i.e., without another winding layer in between, and preferably an outer winding layer that bears against the outer circumference of the inner winding layer.(Both) the inner winding layer (and the outer winding layer) of each winding has a plurality of turns arranged one behind the other in the longitudinal direction of the stator tooth (in the axial direction of the stator in an axial flux machine, and in the width direction of the stator teeth in a radial flux machine (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine)). In an axial flux machine, the longitudinal direction of the stator tooth(s) extends in a direction between the yoke and the air gap (which is formed between the rotor and stator).An outer winding head, which is a portion of the winding (of an axial flux machine) and extends along a radially first or outer edge of the stator tooth in the circumferential direction, is supported on the radially first or outer edge of the stator tooth by means of at least one support web extending in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine).
[0014] In other words, the winding is supported uniformly across all turns in the area of its winding heads (sections of the windings that extend in the circumferential direction) by means of one or more axially extending support webs.
[0015] This has the advantage that the outer winding head is positioned at a predefined distance from the radially outer edge of the stator tooth via the support web. A coolant can enter this distance to cool the windings or the corresponding stator tooth. The predefined distance (between the stator tooth and the outer winding head) created by the support web thus enables effective stator cooling.
[0016] The stator according to the disclosure is advantageously constructed like a stator known from the prior art, which was described above in connection with the prior art, except for the properties according to the disclosure.
[0017] In addition to or as an alternative to the support web on the radially outer edge of the stator tooth, the disclosure provides that an inner winding overhang, which is a section of the winding and extends in the circumferential direction along a radially second or inner edge of the stator tooth, which is opposite the radially outer edge of the stator tooth, is supported on the radially inner edge of the stator tooth by means of at least one support web extending in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine). This has the advantage that not only the winding sections that extend along the radially outer edge of the stator cores, i.e., the outer winding overhang, but also the winding sections that extend along the radially inner edge of the stator cores, i.e., the inner winding overhang, can be effectively cooled.
[0018] Furthermore, it is very useful to form a gap between the inner winding layer of the outer winding overhang and the radially outer edge of the stator tooth in the sections where no support web is provided, and / or to form a gap between the inner winding layer of the inner winding overhang and the radially inner edge of the stator tooth in the sections where no support web is provided. This gap allows a coolant to be guided along the circumferential direction of the radially inner edge and / or the radially outer edge of the respective stator core. This gap thus ensures effective cooling of the stator.
[0019] Accordingly, it is particularly useful if the gap is designed and configured to guide coolant. In other words, the gap between the inner winding layer of the outer and / or inner winding overhang and the radially outer and / or radially inner edge of the stator tooth defines a stator tooth-winding overhang coolant channel. In this way, the gap can fulfill the aforementioned advantages with regard to effective stator cooling.
[0020] Furthermore, it can be provided that the sections of the winding of a stator tooth extending in the width direction of the stator teeth (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine) are each received in a winding slot that extends laterally of the stator tooth in the width direction of the stator teeth (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine), and the gap guides the coolant into the winding slots that laterally border the stator tooth. In other words, the gap is directly fluidically connected to a coolant channel formed in the winding slot. Thus, the gap not only serves to guide coolant along the radially inner and / or radially outer edge of the stator tooth but also serves to supply the coolant into coolant gaps provided in the winding slot.
[0021] In this context, it can be provided that the first turns of the sections of the winding extending in the width direction of the stator teeth (in the radial direction in the case of an axial flux machine; in the axial direction in the case of a radial flux machine) are arranged offset from one another, viewed in the circumferential direction, relative to the second turns of the sections of the same winding extending in the width direction of the stator teeth (in the radial direction in the case of an axial flux machine; in the axial direction in the case of a radial flux machine).In this way, a plurality of stator tooth winding coolant channels (extending in the width direction of the stator teeth (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine)) are arranged in the sections of the stator teeth extending in the width direction of the stator teeth between the inner winding layer of the winding of a stator tooth and the associated stator tooth. These channels further improve the cooling of the stator, specifically in a radial direction of the stator.
[0022] In addition, it is desirable that a coolant inlet is arranged axially next to the outer winding head on both sides of the at least one support web on a side of the stator facing away from a rotor, or that a coolant inlet is arranged axially next to the outer winding head on only one side of the at least one support web on a side facing away from a rotor and that a coolant outlet is arranged on the other side of the at least one support web on the side facing away from the rotor, and that the support web in this case is designed as a partition wall between the coolant inlet and the coolant outlet.
[0023] If, in a first case of coolant guidance, a coolant inlet is arranged axially next to the outer winding overhang on both sides of the at least one support web on a side of the stator facing away from the rotor, a coolant can flow on both sides of the support to a coolant channel in the winding slot. The coolant then flows, starting from the radially outer edge of the stator tooth, into the coolant channels arranged on both sides of the stator tooth and extending in the width direction of the stator teeth (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine), between the stator tooth and the associated winding. This ensures effective cooling of the stator.
[0024] If, in a second case of coolant guidance, a coolant inlet is arranged axially next to the outer winding head on only one (first) side of the at least one support web on a side facing away from a rotor and a coolant outlet is arranged on the other (second) side of the at least one support web on the side facing away from the rotor and the support web in this case is designed as a partition wall between the coolant inlet and the coolant outlet, this represents an alternative to the first case of coolant guidance. In this case, a coolant initially flows onto one (first) side of the support and from there into the (first) stator tooth winding coolant channels extending in the width direction of the stator teeth (in the radial direction in an axial flux machine; in the axial direction in a radial flux machine) and located on the same (first) side.The coolant then flows within these stator tooth winding coolant channels located on the (first) side along the radial extension of the respective stator tooth to the inner winding overhang. Here, the coolant flow is directed into (second) stator tooth winding coolant channels located on the other (second) side of the support web and extending in the width direction of the stator teeth (in the radial direction in an axial-flow machine; in the axial direction in a radial-flow machine) and then flows back in these (second) stator tooth winding coolant channels to the outer winding overhang. In the gap on the other (second) side of the support web, which is connected to the coolant drain, the coolant collects between the outer winding overhang and the stator tooth and flows from there to the coolant drain. The coolant drain carries the coolant away from the stator tooth and its associated winding.
[0025] Further preferably, it can be provided that a central support web is arranged in the center of the circumferential extent of the radially outer edge of the stator tooth, and at least one lateral support web is arranged at least on one side or to the side of the central support web. These lateral support webs support a better coolant supply to the areas of the winding facing away from the coolant inlet. The lateral support webs prevent premature "flow" of the cooling medium into the stator tooth-winding coolant channels.
[0026] Advantageously, the central support web extends (almost) over the entire length of the radially outer edge of the stator tooth in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine), and the lateral support webs, starting from a side facing a coolant inlet, do not extend over the entire length of the radially outer edge of the stator tooth, for example only over half of it, in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine). If the lateral support webs do not extend over the entire axial extent of the radially outer edge of the stator tooth, the coolant can only flow into the stator tooth winding coolant channels behind the end of the lateral support webs. This embodiment guarantees a uniform distribution of the coolant into the stator tooth winding coolant channels.Alternatively, the lateral support webs could extend over the entire axial extent of the radially outer edge of the stator tooth, but have local interruptions / recesses. In this case, the coolant can flow laterally through these interruptions / recesses into the stator tooth winding coolant channels. This alternative also ensures an even distribution of the coolant into the stator tooth winding coolant channels.
[0027] It is also conceivable for the at least one support web to be wedge-shaped and for its height to increase from a side facing a rotor / a side facing away from the yoke to a side facing away from the rotor / a side facing the yoke. Due to the commonly used manufacturing process (punch-winding process), the outer contours of the stator tooth do not run parallel to the axis of rotation. During assembly / production, the windings are joined from the tooth tip (radially inner edge of the stator tooth) of the stator tooth along its radial extent towards the yoke (and thus towards the radially outer edge of the stator tooth), so that they must be joined over the largest interfering contour of the stator tooth (namely along the radial extent of the stator tooth). The wedge-shaped support web preferably compensates for this resulting shape error.
[0028] In the case of a two-layer winding, it is advantageous for each turn to consist of an inner section of the inner winding layer and an outer section of the outer winding layer. The inner section and the outer section are located at the same height in the longitudinal direction of the stator tooth (in the axial direction in an axial flux machine).
[0029] Furthermore, the above-defined object is achieved by an axial flux machine, preferably in an I-configuration, which has at least one stator according to the disclosure and a rotor, in particular a disk-shaped rotor. If two stators are provided, the rotor is arranged between the two stators. This axial flux machine has the advantages associated with the stator(s) according to the disclosure. The disclosure is explained below with the aid of drawings. They show:
[0030] Fig. 1 is a perspective view of a section of the stator in the area of the outer winding head;
[0031] Fig.2 is a perspective view of a section of the stator in the area of the inner winding head;
[0032] Fig. 3 is a perspective view of a section of the stator in the region of the radially outer edge of stator teeth showing a coolant guide in a first embodiment;
[0033] Fig. 4 is a perspective view of a section of the stator in the region of the radially outer edge of stator teeth showing a coolant guide in a second embodiment;
[0034] Fig. 5 is a plan view of the radially outer edge of a stator tooth with a central support web and two lateral support webs; and
[0035] Fig. 6 shows a section in longitudinal section of the stator with support web.
[0036] The figures are merely schematic and serve only to clarify the invention. The same elements are designated by the same reference numerals.
[0037] Fig. 1 is a perspective view of a section of a stator 1 of an axial flux machine with two adjacent stator teeth 2, 3. Fig. 1 shows the rear side of the stator teeth 2, 3, which are not actually visible in this view, but are nevertheless labeled for easier understanding. The first stator tooth 2 is wound completely around a first winding 4. The second stator tooth 3 is also wound completely around a second winding 5. Here, only sections of the windings 4, 5 can be seen (extending mainly in the circumferential direction U). In the area in which the first stator tooth 2 and the second stator tooth 3 face each other, the first winding 4 is arranged adjacent to the second winding 5. The first winding 4 faces the adjacent second winding 5 in the area of its radial extension (only partially shown here).A yoke 6 magnetically connects stator teeth 2, 3 and all other stator teeth of stator 1 (not shown here). In this illustration, yoke 6 actually covers stator teeth 2, 3, which are nevertheless labeled.
[0038] The first winding 4 has an inner winding layer 4.1, which is arranged in the immediate vicinity of the first stator tooth 2. The first winding 4 has an outer winding layer 4.2, which bears against the outer circumference of the inner winding layer 4.1. This structure also applies to the second winding 5 (and all further windings). The second winding 5 has an inner winding layer 5.1, which is arranged in the immediate vicinity of the second stator tooth 3. The second winding 5 has an outer winding layer 5.2, which bears against the outer circumference of the inner winding layer 5.1. The second winding 5 of the second stator tooth 3 is only partially shown here. The outer winding layer 4.2 or 5.2 is further away from the associated stator tooth 2 or 3, as viewed in the radial direction R, than the corresponding inner winding layer 4.1 or 5.1. It can be seen that the outer winding layers 4.2, 5.2 adjacent windings 4, 5 face each other in the section of the radial extension of the respective windings (shown only minimally here).
[0039] Both the inner winding layer 4.1 or 5.1 and the outer winding layer 4.2 or 5.2 of each winding 4, 5 (and also of each other winding) have a plurality of windings 7 arranged side by side, one behind the other, or one above the other, as viewed in the axial direction A of the stator 1. The windings of a winding are arranged in rows one above the other or one behind the other (see cutting edge of winding 5).
[0040] In the present Fig. 1, the outer winding overhangs 4.3, 5.3 of the respective windings 4, 5 are mainly shown. It can be seen that the inner winding layer 4.1, 5.1 of the outer winding overhangs 4.3, 5.3 each rests with its side facing the stator tooth 2, 3 on a support web 8. The support web 8 is provided approximately in the middle of the circumferential extent of the radially outer edge of the stator tooth 2, 3. On each side of the support web 8, a gap 9, 10 is formed between the radially outer edge of the stator tooth 2, 3 and the outer winding overhang or the inner winding layer 4.1, 5.1 of the outer winding overhang 4.3, 5.3. This gap 9, 10 is suitable and intended for guiding coolant along the radially outer edge of the stator tooth 2, 3.
[0041] Furthermore, the winding slots 11, indicated as dashed lines, can be seen. These accommodate the adjacent windings 4, 5 of the adjacent stator teeth 2, 3. The winding slots 11 are provided between the adjacent stator teeth 2, 3 and extend in the radial direction R. The winding slots 11 are also not actually visible in this illustration, as they are concealed by the yoke 6. However, they are nevertheless shown (as dashed lines) for the sake of clarity.
[0042] Fig. 2 shows a perspective view of a section of the stator in the area of the inner winding overhangs 4.4, 5.4 of the adjacent windings 4, 5. A support web 8 is also provided on the radially inner edge of each stator tooth 2, 3. The support web 8 is located approximately in the middle of the circumferential extent of the radially inner edge of the stator tooth 2, 3. Here, too, the inner winding layer 4.1, 5.1 of the inner winding overhang 4.4, 5.4 rests on the support web 8. Accordingly, here too, a gap 9, 10 is formed on both sides of the support web 8 for guiding the coolant between the radially inner edge of the stator tooth 2, 3 and the inner winding head 4.4, 5.4 or the inner winding layer 4.1, 5.1 of the inner winding head 4.4, 5.4.
[0043] Also in Fig. 2, the winding slots 11 extending in the radial direction R can be seen, which accommodate the adjacent windings 4, 5.
[0044] Fig. 3 shows a perspective view of a section of the stator 1 in the region of the radially outer edge of stator teeth 2, 3, showing a coolant guide along the first stator tooth 2 in a first embodiment. To improve the clarity of the coolant flow, the windings are not shown here. It can be seen that coolant inlets 12, 13 are provided on a side of the stator facing away from a rotor (not shown), axially next to the radially outer edge of the stator tooth 2. The coolant inlet 12 is located on one (first) side of the support web 8 and supplies coolant to the gap 9 (only indicated here). The coolant inlet 13 is located on the other (second) side of the support web 8 and supplies coolant to the gap 10 (only indicated here).
[0045] The coolant flow is represented by the arrows ZL. It can be seen that the coolant, starting from the coolant inlets 12, 13, initially flows along the support web and then along the radially outer edge of the stator tooth 2. The coolant then flows into the winding slot 11. Specifically, the coolant flows from the radially outer edge of the stator tooth 2 into stator tooth-winding coolant channels (not shown here) extending in the radial direction and formed between the winding and the stator tooth. Thus, the coolant initially flows along the radially outer edge of the stator tooth 2, then along its radial extension, up to the radially inner edge of the stator tooth 2.
[0046] Fig. 4 shows a perspective view of a section of the stator 1 in the region of the radially outer edge of stator teeth 2, 3, showing a coolant guide along the first stator tooth 2 in a second embodiment. Here, too, the windings are not shown to improve the visualization of the coolant flow.
[0047] The coolant inlet 13 is also provided here. Furthermore, a coolant outlet 14 is provided on a side of the stator 1 facing away from the rotor (not shown), axially next to the radially outer edge of the stator tooth 2. The support web 8 forms a partition between the gap 9 and the gap 10. Accordingly, the coolant flows from the coolant inlet 13, first along the support web 8 (in the axial direction A) and then along the radially outer edge of the stator tooth 2 (in the circumferential direction U). From there, the coolant enters the winding groove 11 located on the side of the gap 10 (here the right side of the stator tooth 2) or into the stator tooth winding coolant channels (not shown) formed there. The coolant thus flows from here along the radial extension of the stator tooth 2 to the radially inner edge of the stator tooth 2 (not shown).From here, the coolant exits the winding slot 11 and flows (along the circumferential direction) along the radially inner edge of the stator tooth 2. From there, the coolant enters the winding slot 11 located on the side of the gap 9 (here the left side of the stator tooth 2) or into the stator tooth-winding coolant channels (not shown) formed there. Thus, the coolant flows from here back along the radial extension of the stator tooth 2 to the radially outer edge of the stator tooth 2. Here, the coolant then flows first along the radially outer edge of the stator tooth 2 in the gap 9 (in the circumferential direction U) and then along the support web 8 into the coolant outlet 14. From here, the heated coolant is carried away from the stator tooth 2 (and its winding).
[0048] Fig. 5 shows a plan view of the radially outer edge of a stator tooth 2 with a central support web 8.1 and two lateral support webs 8.2. The central support web 8.1 is arranged in the middle of the circumferential extent of the radially outer edge of the stator tooth 2. The lateral support webs 8.2 are each arranged at a distance in the circumferential direction U on both sides of the central support web 8.1. The support webs 8.1, 8.2 all extend from the yoke region 6 or the side facing away from a rotor in the axial direction A. The central support web 8.1 extends significantly longer in the axial direction A than the lateral support webs 8.2. The lateral support webs 8.2 are approximately only half as long as the central support web 8.1.
[0049] The coolant inlet 12 (here only one coolant inlet) is also shown. The coolant flow is represented by the arrows ZL. Here it can be seen that starting from the coolant inlet 12 laterally next to the lateral support webs 8.2 (and thus also laterally of the central support web 8.1), the coolant initially flows along the support webs 8.1, 8.2. The coolant that flows laterally outside the lateral support webs 8.2 (i.e. on a side of the lateral support webs 8.2 facing away from the central support web 8) enters the winding slot 11 after a short distance, e.g. after less than a quarter of the axial extent of the radially outer edge of the stator tooth 2. The coolant that flows between the lateral support webs 8.2 and the central support web 8.1 only enters after a relatively long distance, e.g.only after approximately more than three-quarters of the axial extent of the radially outer edge of the stator tooth 2, into the winding slot 11. In other words, the coolant flowing outside the support webs 8.1, 8.2 travels a significantly shorter distance in the axial direction A than the coolant flowing between the support webs 8.1, 8.2. The central support web 8 divides the coolant flow such that part of the coolant flows into the winding slot 11 on one side of the stator tooth 2, and the remaining part of the coolant flows into the winding slot 11 on the other side of the stator tooth 2.
[0050] Here, the turns 7 of the winding 4 of the stator tooth 2 are also shown in the form of circles.
[0051] Fig. 6 shows a section in longitudinal section of the stator 1 with support web 8. It can be seen that the outer contour of the stator tooth 2 does not run parallel to the axis of rotation RA of the stator 1. Starting from the edge of the stator tooth 2 facing away from the yoke 6 towards the yoke 6, the outer contour of the stator tooth 2 has a decreasing distance to the axis of rotation RA. The deformation, which results in the outer contour of the stator tooth 2 not being parallel to the axis of rotation RA of the stator 1, occurs when the winding 4 is joined to the stator tooth 2. The joining takes place along the arrow F, i.e. starting from the edge of the stator tooth 2 facing away from the yoke 6 towards the yoke 6.
[0052] Accordingly, the support web 8 is wedge-shaped. The support web 8 increases in height from the edge of the stator tooth 2 facing away from the yoke 6 toward the yoke 6. The support web 8 is designed such that the outer contour of the stator tooth 2, which is partially formed by the support web 8, is parallel to the rotation axis RA, at least in the region of the support web 8. In this way, the shape of the support web 8 compensates for the deformation of the outer contour of the stator tooth 2.
[0053] It should be noted that even if only one or two stator teeth 2, 3 of an axial flux machine with associated winding 4, 5 are shown in the above figures, the corresponding previously described structure applies to all stator teeth or their windings.
[0054] 1 stator
[0055] 2 first stator tooth
[0056] 3 second stator tooth
[0057] 4 first winding
[0058] 4.1 inner winding layer of the first winding
[0059] 4.2 outer winding layer of the first winding
[0060] 4.3 outer winding head of the first winding
[0061] 4.4 inner winding head of the first winding
[0062] 5 second winding
[0063] 5.1 inner winding layer of the second winding
[0064] 5.2 outer winding layer of the second winding
[0065] 5.3 outer winding head of the second winding
[0066] 5.4 inner winding head of the second winding
[0067] 6 yoke
[0068] 7 turns
[0069] 8 Support bridge
[0070] 9 (first) gap
[0071] 10 (second) gap
[0072] 11 Winding groove
[0073] 12 Coolant inlet
[0074] 13 Coolant inlet
[0075] 14 Coolant drain
[0076] A axial direction
[0077] F Joining direction of a winding around a stator tooth
[0078] KMS coolant flow
[0079] R Radial direction
[0080] RA rotation axis of the stator
[0081] U circumferential direction
Claims
Patent claims 1 . Stator (1) with a plurality of mutually adjacent stator teeth (2, 3), wherein at least one stator tooth (2, 3) is wound completely by a winding (4, 5) and the winding (4, 5) has at least one inner winding layer (4.1, 5.1) which is arranged in the immediate vicinity of the stator tooth (2, 3) or directly surrounds the stator tooth (2, 3), and wherein the winding (4, 5) has a plurality of turns (7) arranged next to one another as viewed in the longitudinal direction of the stator tooth (2, 3), characterized in that an outer winding head (4.3, 5.3), which is a section of the winding (4, 5) and extends along a radially first or outer edge of the stator tooth (2, 3) in the circumferential direction (U), by means of at least one winding layer extending in the longitudinal direction of the stator tooth (2, 3) Support web (8) is supported on the radially first or outer edge of the stator tooth (2, 3), and / or an inner winding head (4, 4, 5).4), which is a section of the winding (4, 5) and extends in the circumferential direction (U) along a radially second or inner edge of the stator tooth (2, 3), which is opposite the radially first or outer edge of the stator tooth (2, 3), is supported on the radially second or inner edge of the stator tooth (2, 3) by means of at least one support web (8) extending in the longitudinal direction of the stator tooth (2, 3).
2. Stator (1) according to claim 1, characterized in that a gap (9, 10) is formed between the inner winding layer (4.1, 5.1) of the outer winding head (4.3, 5.3) and the radially first or outer edge of the stator tooth (2, 3) at the sections where no support web (8) is provided, and / or a gap (9, 10) is formed between the inner winding layer (4.1, 5.1) of the inner winding head (4.4, 5.4) and the radially second or inner edge of the stator tooth (2, 3) at the sections where no support web (8) is provided.
3. Stator (1) according to claim 2, characterized in that the gap (9, 10) is provided and designed to guide coolant.
4. Stator (1) according to one of claims 2 or 3, characterized in that the sections of the winding (4, 5) of a stator tooth (2, 3) extending in the width direction of the stator tooth (2, 3) are each received in a winding groove (11) which extends laterally along the stator tooth (2, 3) in the width direction of the stator tooth (2, 3), and the gap (9, 10) guides the coolant into the winding grooves (11) which laterally enclose the stator tooth (2, 3).
5. Stator (1) according to one of claims 2 to 4, characterized in that at least one or in each case one coolant inlet (12, 13) is arranged axially next to the outer winding head (4.3, 5.3) on both sides of the at least one support web (8) on a side of the stator (1) facing away from a rotor, or a coolant inlet (13) is arranged axially next to the outer winding head (4.3, 5.3) on only one side of the at least one support web (8) on a side facing away from the rotor, and a coolant outlet (14) is arranged on the other side of the at least one support web (8) on the side facing away from the rotor, and the support web (8) is designed in this case as a partition wall between the gaps (9, 10) formed by the support web (8).
6. Stator (1) according to one of claims 1 to 5, characterized in that a central support web (8.1) is arranged in the middle of the circumferential extent of the radially first or outer edge of the stator tooth (2, 3) and at least one lateral support web (8.2) is arranged on at least one side laterally of the central support web (8.1).
7. Stator (1) according to one of claims 1 to 6, characterized in that a central support web (8.1) is arranged in the middle of the circumferential extent of the radially first or outer edge of the stator tooth (2, 3) and at least one lateral support web (8.2) is arranged laterally from the central support web (8.1).
8. Stator (1) according to claim 7, characterized in that the central support web (8.1) extends substantially over the entire length of the radially first or outer edge of the stator tooth (2, 3) in the longitudinal direction of the stator tooth (2, 3), and the lateral support web(s) (8.2), starting from a side facing a coolant inlet (12), do not extend over the entire length of the radially first or outer edge of the stator tooth (2, 3) in the longitudinal direction of the stator tooth (2, 3).
9. Stator (1) according to one of claims 1 to 8, characterized in that the at least one support web (8) is wedge-shaped and its height extension increases from a side facing a rotor to a side facing away from the rotor.
10. Axial flux machine, which has at least one stator (1) according to one of the preceding claims and a rotor, wherein in the case of two stators (1) the rotor is arranged between the two stators (1 ).