Claw pole stators for transversal flux motors and segments for claw pole stators

Abstract

The present invention relates to a claw pole stator (1, 29) for a transversal flux motor (2), wherein the claw pole stator (1, 29) is formed by a number of segments (3), the segments (3) being arranged side by side along a circumferential direction (4) to form a ring-shaped claw pole stator (1), wherein each segment (3) originates from an inner peripheral surface (5) and extends along a radial direction (6) towards an outer peripheral surface (7), and is bounded in the circumferential direction (4) by a first side surface (8) and a second side surface (9) and in the axial direction (10). ) by a first end face (11) and a second end face (12), wherein each segment (3) is connected to another segment (3) via side faces (8, 9) to form a ring-shaped claw pole stator (1), wherein adjacently arranged segments (3) are in contact with each other via a first contact surface (13) on the first side face (8) or a second contact surface (14) on the second side face (9), and form a form-fit connection (15) in the circumferential direction (4) via the contact surfaces (13, 14).

Description

[Technical field]

[0001] The present invention relates to a claw pole stator for a transversal flux motor and a segment for a claw pole stator. A transversal flux motor is an electric drive that can be used as a generator and as an electric machine. A transversal flux motor usually includes a stator and a rotor. The rotor is referred to here as a holder for permanent magnets, whereas the stator has a coil assembly. The rotor or the stator may be coupled to a shaft that is driven by the transversal flux motor (operation as an electric machine) or transfers rotary motion to the transversal flux motor (operation as a generator).

[0002] An electric axial flux machine is known, for example, from DE 10 2009 021 703 C1, which proposes, inter alia, that the flux yoke be formed from a number of ring-cylinder segments which are in contact with one another via their circumferentially facing side surfaces.

[0003] It is particularly preferred to manufacture the claw pole stator by powder metallurgy. For this purpose, powder is fed in a press in a predefined mass and pressed. A subsequent heat treatment serves to remove organic constituents. In particular, the powder particles have an electrically insulating coating. High-precision components can be produced by powder metallurgy production.

[0004] It has now been found that the special geometries of claw pole stators cannot be produced without problems by powder metallurgy, and in particular the tapered poles of claw pole stators cannot be produced without difficulty and with high uniformity and density.

[0005] Starting from this, it is an object of the present invention to at least partially solve the problems described in connection with the prior art, in particular to propose a claw pole stator having a configuration that is particularly suitable for production by powder metallurgy.

[0006] To achieve this object, a claw-pole stator is proposed as set forth in the characterizing part of claim 1 and a segment for a claw-pole stator as set forth in claim 11. Advantageous developments are the subject of the dependent claims. The features individually set forth in the claims can be combined with one another in a technically significant manner and can be supplemented by the embodiments set forth in the description and the details in the drawings, whereby further variants of the invention are shown.

[0007] The problem is solved by a claw pole stator for a transversal flux motor, the claw pole stator being formed by a number of segments arranged next to each other in the circumferential direction or forming a ring-shaped claw pole stator, each segment extending from an inner circumferential surface toward an outer circumferential surface in the radial direction and being bounded in the circumferential direction by a first side surface and a second side surface and in the axial direction by a first end surface and a second end surface, each segment being connected to at least one further segment via the side surfaces to form the ring-shaped claw pole stator, the segments arranged adjacent to each other being in contact with each other via a first contact surface of the first side surface or a second contact surface of the second side surface of the respective segment and forming a positive-locking connection in the circumferential direction via the contact surfaces.

[0008] In particular, a first segment is in contact with an adjacently arranged second segment via a first contact surface or a second contact surface of the second segment. If the two segments are identical to one another, the first segment is in contact with the second segment via the first contact surface of the first segment (directly or directly) via the contact surface of the second segment. This also applies to the other second side of the first segment and to the second contact surface arranged there.

[0009] Here, a segmentation of the claw pole stator is proposed. The individual segments can be produced by means of a compactly designed die of a press tool. In particular, such special measures can be realized relatively simply in order to produce the most uniform and dense possible production of the segments.

[0010] However, the segmentation of the claw-pole stator creates the problem of assembling the segments into a ring-shaped claw-pole stator. On the one hand, it is desirable to be able to handle the segments well, and on the other hand, it is desirable to be able to achieve as precise a positioning of the segments as possible relative to one another. This can be achieved or guaranteed in the present invention by the construction of a positively-locking connection in the circumferential direction between adjacently arranged segments. The positively-locking connection is generated by the mutual engagement of at least two connection pairs (here segments). As a result, the connection pairs cannot be disengaged even without force transmission or when the force transmission is interrupted. In other words, in a positively-locking connection, one connection pair is in the way of the other connection pair (here with respect to the relative movement in the circumferential direction).

[0011] The individual segments can be joined together in a ring-shaped claw-pole stator by means of positively-locking connections. In particular, the segments can be arranged on a holder, which orients or holds the segments in an oriented manner at least via their inner or outer circumferential surface. In this case, the segments are preferably joined together, for example, via a plastic, which is supplied to the claw-pole stator in liquid form, for example, and then hardens.

[0012] The structure of the claw pole stator is described below. Two claw pole stators are arranged next to each other along the axial direction, with both claw pole stators in contact with each other via their end faces. Each claw pole stator has a number of magnetic poles, which extend along the axial direction starting from the bottom face. The first magnetic poles of the first claw pole stator and the second magnetic poles of the second claw pole stator are arranged alternately and adjacent to each other along the circumferential direction, and overlap each other in the axial direction, but spaced apart from each other. The magnetic poles may be arranged on the inner or outer circumferential surface. The claw pole stators are then in contact with each other via their end faces on the outer or inner circumferential surface. In the intermediate chamber of the claw pole stator, coils can be arranged annularly in the circumferential direction between the claw pole stators, between the end faces in the axial direction and between the end faces and the magnetic poles in the radial direction that are in contact with each other. It is likewise possible to arrange another pair of claw pole stators together with the coils of the first pair. This allows the creation of polyphase transversal flux motors, which can provide electrical outputs typically ranging from 0.01 kW up to over 5000 kW.

[0013] The end faces of the claw pole stator may be provided with positioning aids which cooperate with corresponding positioning aids on the oppositely situated end face (eg protrusions and recesses).

[0014] In particular, at least one of the contact surfaces extends in a meander shape along the radial direction between a first radius and a second radius. By "meander shape" is meant in particular curvature radii with curvatures, in particular oriented alternately with respect to the radial direction. A "meander shape" may be a path in which the contact surface extends on both sides of an imaginary line that is central or centered relative to the path of the contact surface and parallel to the radial direction.

[0015] In particular, the magnetic poles are arranged radially outside or inside the contact surface.

[0016] Each of the segments is provided with a contact surface on its side surface, the contact surface including a partial surface of the side surface, in particular the contact surface extends in the axial direction over the respective length of the side surface, preferably the contact surface extends in the radial direction over only a portion of the length of the side surface.

[0017] Along the radial direction, the contact surfaces extend in a meandering manner, with the meandering of the contact surfaces resulting in a form-locking connection with the adjacently arranged segments.

[0018] Such a meander-shaped (but now acute) path of the contact surface is realised, for example, by a dovetail configuration of the contact surface.

[0019] Preferably, at least one of the contact surfaces has a minimum radius of curvature along the meander-shaped path of at least 1.0 mm, preferably 2.0 mm, which reduces the risk of crack formation in the segments, which may occur in the sharp configurations (e.g. dovetails) of very form-fit connections.

[0020] In particular, at least one contact surface has an exclusively curved shape along a meander-shaped path, i.e. in particular in the radial direction, there are no straight line areas of the contact surface, i.e. each point of the contact surface along the radial direction is defined by a (variable along the radial direction) radius of curvature.

[0021] Preferably, at least one contact surface extends along a meander-shaped path over a length that is greater than the radial distance between the first and second radii by a factor of at least 1.5, in particular by a factor of at least 2, i.e. the contact surface is extended by the meander-shaped path (relative to a straight radial path between the first and second radii).

[0022] The increased contact surface further increases the strength of the joined claw pole stator. Furthermore, the meander-shaped paths and the increased contact surface reduce play and relative movement between the segments, which allows for improved handling of the claw pole stator, for example for placement in a carrier.

[0023] According to a first configuration, each segment includes a plurality of magnetic poles.

[0024] According to the second embodiment, each segment has exactly one (single) magnetic pole. With such segments, a particularly compact die of the press tool used to manufacture the segments can be used. Furthermore, it is then possible to take additional measures for a more uniform density in the pressed product in a simple and inexpensive manner.

[0025] Segmentation allows for an inexpensive and highly accurate production of the claw-pole stator, since on the one hand, extremely small segments can be produced with high precision, and on the other hand, the segments can be precisely oriented and positioned relative to one another via centering devices (e.g. carriers). The highly accurate shape of the claw-pole stator produced in this way can then be fixed by a fastening procedure (e.g. embedding in plastic).

[0026] In particular, it is proposed that each of the segments is manufactured by powder metallurgy pressing and heat treatment.

[0027] Preferably, the claw pole stator is formed exclusively by identically configured segments, the segments having first contact surfaces which form a positively-locking connection with second contact surfaces of adjacently arranged identical segments.

[0028] In particular, the claw pole stator has a cylindrical contour formed by the outer or inner peripheral surface of the segments, and the outer and inner peripheral surfaces are formed by the magnetic poles of the segments, and the peripheral surfaces have a difference of up to 50 μm, particularly up to 25 μm, from the cylindrical contour.

[0029] In particular, the segments are then fixed to one another in their position, for example by embedding them in plastic.

[0030] A segment is proposed for a claw pole stator, in particular for the claw pole stator specifically described herein, which extends from an inner peripheral surface along a radial direction towards an outer peripheral surface and is defined in the circumferential direction by a first side surface and a second side surface and in the axial direction by a first end surface and a second end surface. The segment can be connected to at least one further segment via the side surfaces to form a ring-shaped claw pole stator, with adjacently arranged segments contacting each other via a first contact surface of the first side surface or via a second contact surface of the second side surface. The contact surfaces are shaped in such a way that a form-fitting connection can be formed in each case in the circumferential direction with a complementary shaped contact surface of an adjacently arranged segment via the contact surface.

[0031] In particular, at least one of the contact surfaces (preferably both) extends parallel to the axial direction.

[0032] In particular, the poles of the segments extend axially from the base and taper, the poles having a maximum cross-section and a minimum cross-section in the region of the taper, respectively transverse to the axial direction, the ratio of the maximum cross-section to the minimum cross-section being at least 2, preferably at least 3.

[0033] In particular, the segments are manufactured by powder metallurgy pressing and heat treatment.

[0034] According to another aspect, a transversal flux motor is proposed, which includes at least a stator and a rotor, where the stator includes at least two of the claw pole stators described above, where the first magnetic poles of the first claw pole stator and the second magnetic poles of the second claw pole stator are arranged alternately and adjacent to each other along the circumferential direction and overlap each other in the axial direction, where the claw pole stators are arranged relative to each other such that the magnetic poles extend from the bottom surface toward the other claw pole stator along the axial direction.

[0035] The axial direction is oriented parallel to the rotation axis of the transversal flux motor.

[0036] In particular, the rotor extends in a ring shape and has a number of permanent magnets along the circumferential direction, with an annular gap being provided between the rotor and the stator in the circumferential direction, the gap being at most 350 μm, in particular at most 250 μm, preferably 150 μm, in the radial direction, with the gap having a difference of at most 50 μm, in particular at most 25 μm.

[0037] Statements made for claw pole stators also apply to segment and / or transversal flux motors and vice versa.

[0038] Transversal flux motors can be used especially for electrically powered bicycles (pedelecs).

[0039] For the avoidance of doubt, the numerals used herein ("first", "second", ...) primarily serve (solely) to distinguish between a plurality of similar objects or dimensions, i.e., do not necessarily establish a relationship and / or order between these objects and / or dimensions, in particular. Where a relationship and / or order is necessary, this is either explicitly described herein or will be apparent to one of ordinary skill in the art upon consideration of the specifically described configurations.

[0040] In the following, the present invention and technical field will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the illustrated embodiment. In particular, unless expressly described differently, it is also possible to extract partial aspects of the specific examples described in the drawings and combine them with other components and aspects described in this specification and / or the drawings. It should be noted that the drawings and especially the size relationships shown are merely schematic. The same reference numerals indicate the same objects, so that in some cases, the descriptions in other drawings can be supplementarily cited. [Brief description of the drawings]

[0041] [Figure 1] FIG. 1 is an exploded perspective view of a transversal flux motor. [Diagram 2] FIG. 2 is a perspective view showing the transversal flux motor shown in FIG. 1, with a part in section. [Diagram 3] FIG. 3 is a perspective view showing a portion of the transversal flux motor shown in FIGS. 1 and 2. [Figure 4] FIG. 2 is a perspective view showing a claw pole stator. [Diagram 5] FIG. 2 is a first perspective view showing a segment. [Figure 6] FIG. 6 is a second perspective view of the segment shown in FIG. 5. [Figure 7] FIG. 7 is a side view of the segment shown in FIGS. 5 and 6.

[0042] In Fig. 1, a transversal flux motor 2 is shown in an exploded perspective view. In Fig. 2, the transversal flux motor 2 shown in Fig. 1 is shown in a partially cutaway perspective view. In Fig. 3, a part of the transversal flux motor shown in Figs. 1 and 2 is shown in a perspective view. In the following, Figs. 1 to 3 will be described together.

[0043] The transversal flux motor 2 includes in particular a stator 26 and a rotor 27, where the stator 26 includes here six of the claw pole stators 1, where the first magnetic poles 19 of each first claw pole stator 1 and the second magnetic poles 28 of each second claw pole stator 29 are arranged alternately and adjacent to each other along the circumferential direction 4 and overlapping each other in the axial direction 10. The claw pole stators 1, 29 are arranged relative to each other such that the magnetic poles 19, 28 extend from the bottom surface 22 towards the other claw pole stator 29, 1 along the axial direction 10.

[0044] The axial direction 10 is oriented parallel to the rotation axis 32 of the transversal flux motor 2 .

[0045] The rotor 27 extends in a ring shape and has a number of permanent magnets 30 along the circumferential direction 4. At this time, an air gap 31 extending annularly in the circumferential direction 4 is provided between the rotor 27 and the stator 26.

[0046] Each claw pole stator 1, 29 is formed by a number of segments 3, which are arranged next to each other along a circumferential direction 4 to form a ring-shaped claw pole stator 1, 29. Each segment 3 extends from an inner peripheral surface 5 toward an outer peripheral surface 7 along a radial direction 6 and is defined in the circumferential direction 4 by a first side surface 8 and a second side surface 9 and in the axial direction 10 by a first end surface 11 and a second end surface 12. Each segment 3 is connected to another segment 3 via the side surfaces 8, 9 to form the ring-shaped claw pole stator 1. A form-fitting connection 15 of the segments 3 is not shown in FIGS. 1 to 3.

[0047] The two claw pole stators 1, 29 are arranged next to each other along the axial direction 10, and the two claw pole stators 1, 29 are in contact with each other via the first end faces 11. Each claw pole stator 1, 29 has a number of magnetic poles 19, 28, which extend from a bottom surface 22 along the axial direction 10. The first magnetic poles 19 of the first claw pole stator 1 and the second magnetic poles 28 of the second claw pole stator 29 are arranged alternately and adjacent to each other along the circumferential direction 4, and overlap each other in the axial direction 10, but spaced apart from each other. The magnetic poles 19, 28 are arranged on the outer circumferential surface 7 of the segment 3. The claw pole stators 1, 29 are in contact with each other via the first end faces 11 at the inner circumferential surface 5. In the intermediate chamber of the claw pole stators 1, 29, the coils 33 can be arranged annularly between the claw pole stators 1 in the axial direction 10 between the first end faces 11 and in the radial direction 6 between the first end faces 11 that are in contact with each other in the region of the inner circumferential surface 5 and the magnetic poles 19, 28 on the outer circumferential surface 7.

[0048] FIG. 4 shows a perspective view of one claw pole stator 1. The claw pole stator 1 is formed by a number of segments 3, which are arranged next to each other along the circumferential direction 4 to form a ring-shaped claw pole stator 1. Each segment 3 extends from an inner circumferential surface 5 toward an outer circumferential surface 7 along a radial direction 6 and is defined in the circumferential direction 4 by a first side surface 8 and a second side surface 9 and in the axial direction 10 by a first end surface 11 and a second end surface 12. Each segment 3 is connected to another segment 3 via the side surfaces 8, 9 to form the ring-shaped claw pole stator 1. The segments 3 arranged adjacent to each other are in contact with each other via a first contact surface 13 of the first side surface 8 or a second contact surface 14 of the second side surface of each segment 3 (see also FIGS. 5 to 7), and form a form-fitting connection 15 in the circumferential direction 4 via the contact surfaces 13, 14.

[0049] The positively-locking connection 15 results from the engagement of at least two connection pairs (here segments 3) with one another, such that the connection pairs cannot be disengaged without force transmission or when the force transmission is interrupted. In other words, in the positively-locking connection 15, one connection pair impedes the other connection pair (here with respect to relative movement with respect to one another in the circumferential direction 4). By means of the positively-locking connection 15, the individual segments 3 can be brought together in the ring-shaped claw-pole stator 1.

[0050] The contact surfaces 13, 14 extend in a meandering manner along the radial direction 10 between a first radius 16 and a second radius 17. The magnetic poles 19 are arranged outside the contact surfaces 13, 14 in the radial direction 6. Each side surface 8, 9 of the segment 3 is provided with a contact surface 13, 14. The contact surface 13, 14 comprises a partial surface of the side surface 8, 9. The contact surfaces 13, 14 extend along the axial direction 10 over the entire extension length of the side surface 8, 9, respectively. The contact surfaces 13, 14 extend along the radial direction 6 only over a portion of the extension length of the side surface 8, 9.

[0051] Along the radial direction 6 the contact surfaces 13, 14 run in a meandering manner, with the meandering of the contact surfaces 13, 14 resulting in a form-fitting connection 15 with the adjacently arranged segment 3.

[0052] All segments 3 here are formed identically to one another, so that a first segment 3 contacts a second segment 3 via a first contact surface 13 of the first segment 3 and via a second contact surface 14 of the second segment 3. The same is true for the other second side surface 9 of the first segment 3 and the second contact surface 14 arranged thereon.

[0053] In Fig. 5, one segment 3 is shown in a first perspective view. In Fig. 6, the segment 3 shown in Fig. 5 is shown in a second perspective view. In Fig. 7, the segment 3 shown in Figs. 5 and 6 is shown in a side view. Figs. 5 to 7 are described together below.

[0054] The segments 3 extend from the inner peripheral surface 5 in the radial direction 6 towards the outer peripheral surface 7 and are delimited in the circumferential direction 4 by a first side surface 8 and a second side surface 9 and in the axial direction 10 by a first end surface 11 and a second end surface 12. To form a ring-shaped claw pole stator 1, the segments 3 can be connected to other segments 3 via the side surfaces 11, with adjacently arranged segments 3 being in contact with each other via a first contact surface 13 of the first side surface 8 or via a second contact surface 14 of the second side surface 9. The contact surfaces 13, 14 are shaped in such a way that a form-fitting connection 15 can be formed in each case in the circumferential direction 4 with the complementary shaped contact surface 13, 14 of the adjacently arranged segment 3 via the contact surfaces 13, 14. Both contact surfaces 13, 14 extend parallel to the axial direction 10.

[0055] The pole 19 of the segment 3 extends along the axial direction 10 starting from the bottom surface 22 and tapers. In the region of the taper 23, the pole 19 has a maximum cross section 24 and a minimum cross section 25, each transverse to the axial direction 10.

[0056] The end faces 11, 12 of the segment 3 are provided with positioning aids 34 which cooperate with corresponding positioning aids 34 (here convex and concave) on the oppositely positioned end faces 11, 12 of the adjacently arranged segment of the other claw pole stator 1.

[0057] The contact surfaces 13, 14 extend in a meandering shape along the radial direction 10 between a first radius 16 and a second radius 17.

[0058] The magnetic poles 19 are arranged outside the contact surfaces 13 , 14 in the radial direction 6 .

[0059] Each side surface 8, 9 of the segment 3 is provided with a contact surface 13, 14. The contact surface 13, 14 comprises a partial surface of the side surface 8, 9. The contact surface 13, 14 extends in the axial direction 10 over the entire extension length of the side surface 8, 9, respectively. The contact surface 13, 14 extends in the radial direction 6 over only a part of the extension length of the side surface 8, 9.

[0060] Along the radial direction 6, the contact surfaces 13, 14 run in a meandering shape, with the meandering shape of the contact surfaces 13, 14 forming a form-fitting connection 15 with the adjacently arranged segment 3. The contact surfaces 13, 14 have a minimum radius of curvature 18 along the path of the meandering shape.

[0061] Such a minimum radius reduces the risk of crack formation in the segments 3, which may occur at sharp configurations of the form-fit joint 15 (eg dovetails).

[0062] The contact surfaces 13, 14 here have an exclusively curved shape along a meander-shaped path, i.e. no straight sections of the contact surfaces 13, 14 are provided here in the radial direction 6, i.e. each point of the contact surfaces 13, 14 along the radial direction 6 is formed by a radius of curvature 18 (which varies along the radial direction 6).

[0063] The contact surfaces 13, 14 extend along a meander-shaped path over a length 20 that is a factor greater than the distance 21 between the first radius 16 and the second radius 17 in the radial direction 6. By virtue of the meander-shaped path, the contact surfaces 13, 14 are thus extended in the radial direction 6 (with respect to a straight path in the radial direction 6 between the first radius 16 and the second radius 17) and are thereby increased. [Explanation of symbols]

[0064] 1 First claw pole stator 2 Transversal Flux Motor 3 Segments 4 Circumferential direction 5 Inner surface 6 Radial 7 Outer surface 8. First aspect 9. The Second Aspect 10 Axial Direction 11 First end face 12 Second end face 13 First contact surface 14 Second contact surface 15 Joint 16 First Radius 17 Second Radius 18 radius of curvature 19 magnetic pole 20 Length 21 interval 22 Bottom 23 Tapered section 24 Largest cross section 25 Minimum cross section 26 Stator 27 Rotor 28 Second Pole 29 Second claw pole stator 30 Permanent Magnets 31 void 32 Rotation axis 33 Coil 34 Positioning aid

Claims

1. A claw pole stator (1, 29) for a transversal flux motor (2), the claw pole stator (1, 29) being formed by a number of segments (3) arranged side by side along a circumferential direction (4), each of the segments (3) extending from an inner circumferential surface (5) toward an outer circumferential surface (7) along a radial direction (6) and bounded in the circumferential direction (4) by a first side surface (8) and a second side surface (9) and bounded in the axial direction (10) by a first end surface (11) and a second end surface (12) (12), each of the segments (3) being connected to at least one other segment (3) via the side surfaces (8, 9), the segments (3) arranged adjacent to one another being in contact with one another via a first contact surface (13) at the first side surface (8) or via a second contact surface (14) at the second side surface (9) and forming, via the contact surfaces (13, 14), complementary joints (15) having radii of curvature oriented alternately in the circumferential direction (4) with respect to the radial direction (6), At least one of the contact surfaces (13, 14) extends along the coupling portion (15) in the radial direction (6) between a first radius (16) and a second radius (17); said at least one contact surface (13, 14) having a minimum radius of curvature (18) of at least 1 mm along the path of said joint (15); The segment (3) is formed by powder metallurgy and includes magnetic poles (19, 28); The magnetic pole (19, 28) has a bottom portion having a bottom surface (22), a tapered portion (23) extending from the bottom portion in the axial direction (10) and tapering, and a rectangular parallelepiped tip portion provided at the tip of the tapered portion (23).

2. said at least one contact surface (13, 14) has an exclusively curved path along the path of said connection portion (15); A claw pole stator (1, 29) according to claim 1.

3. said at least one contact surface (13, 14) extends along the path of said connection (15) over a length (20) that is greater than the distance (21) between said first radius (16) and said second radius (17) along said radial direction (6) by a factor of at least 1.5; A claw pole stator (1, 29) according to claim 1 or 2.

4. said claw pole stator (1, 29) being formed exclusively by said identically formed segments (3); A claw pole stator (1, 29) according to any one of claims 1 to 3.

5. A segment (3) for a claw pole stator (1, 29), the segment (3) extending from an inner circumferential surface (5) along a radial direction (6) toward an outer circumferential surface (7), and defined in the circumferential direction (4) by a first side surface (8) and a second side surface (9) and in the axial direction (10) by a first end surface (11) and a second end surface (12), the segment (3) being connectable to at least one other segment (3) via the side surfaces (8, 9) and arranged adjacent to each other. the segments (3) placed on each other are in contact with one another via first contact surfaces (13) on the first side surface (8) or via second contact surfaces (14) on the second side surface (9), the contact surfaces (13, 14) being shaped in such a way that a connection (15) can be formed with a complementary shaped contact surface (13, 14) of an adjacently positionable segment (3) in the circumferential direction (4) with a respective one of the curvature radii oriented alternately in the radial direction (6), At least one of the contact surfaces (13, 14) extends along the coupling portion (15) in the radial direction (6) between a first radius (16) and a second radius (17) of the claw pole stator (1, 29); said at least one contact surface (13, 14) having a minimum radius of curvature (18) of at least 1 mm along the path of said joint (15); formed by powder metallurgy and including magnetic poles (19, 28); The magnetic pole (19, 28) has a bottom portion having a bottom surface (22), a tapered portion (23) extending from the bottom portion in the axial direction (10), and a rectangular parallelepiped tip portion provided at the tip of the tapered portion (23).

6. At least one of the contact surfaces (13, 14) extends parallel to the axial direction (10). A segment (3) according to claim 5.

7. A transversal flux motor (2), comprising at least a stator (26) and a rotor (27), the stator (26) comprising at least two claw-pole stators (1, 29) according to any one of claims 1 to 4, wherein the first magnetic poles (19) of the first claw-pole stator (1) and the second magnetic poles (28) of the second claw-pole stator (29) are arranged alternately and adjacent to each other along a circumferential direction (4) and overlap each other in an axial direction (10).

8. the rotor (27) extends in a ring shape and has a number of permanent magnets (30) along the circumferential direction (4); between the rotor (27) and the stator (26) there is provided an annularly extending air gap (31) in the circumferential direction (4), the air gap (31) being at most 350 μm in the radial direction (6), the air gap (31) having a difference of at most 50 μm; A transversal flux motor (2) according to claim 7.

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