Iron core, stator and rotating motor

Abstract

A core, which is an iron core of a rotor or a stator of an axial gap type rotating electric machine, the core having a block-shaped first component and a plate-shaped second component composed of a powder compact, the first component having a first surface opposite to the second component and a first connecting portion formed on the first surface, the second component having a second surface opposite to the first surface and a second connecting portion formed on the second surface and connected to the first connecting portion, one of the first connecting portion and the second connecting portion being composed of a protrusion and the other being composed of a recess having a shape corresponding to the protrusion, the front shape of the first connecting portion when the first component is observed from the first surface is a ring shape or a discontinuous ring shape with a portion not connected, and the front shape of the second connecting portion when the second component is observed from the second surface is a ring shape or a discontinuous ring shape with a portion not connected.

Description

Technical Field

[0001] The invention relates to an iron core, a stator and a rotating electric machine.

[0002] This application claims the benefit of priority based on Japanese Patent Application No. 2018-141841 filed on July 27, 2018, and all the contents described in the above-mentioned Japanese application are cited. Background Art

[0003] Patent document 1 discloses an axial gap type rotating electrical machine (motor, generator) in which a rotor and a stator are arranged opposite to each other in the direction of the rotating axis of the rotor. The stator used in the rotating electrical machine has: an armature core (iron core) having a back yoke (yoke) and a plurality of teeth; and a coil arranged on each tooth. The yoke is a ring-shaped component. The teeth are block-shaped components protruding from the yoke in the direction of the rotating axis of the rotor.

[0004] The armature core of Patent Document 1 is formed by connecting the teeth and yoke parts that are made separately from each other. More specifically, the yoke part and the teeth are connected by fitting a columnar protrusion provided on the teeth and a concave part (through hole, depression) provided on the yoke part. In Patent Document 1, the yoke part is formed by stacking steel plates, and the teeth part is formed by a powder core (compressed powder compact).

[0005] Patent Document 1: International Publication No. 2007 / 114079 Summary of the invention

[0006] The iron core of the present invention is an iron core possessed by a rotor or a stator of an axial gap type rotating electrical machine.

[0007] The core has a block-shaped first component and a plate-shaped second component made of a powder compact.

[0008] The first member has a first surface opposite to the second member and a first connecting portion formed on the first surface.

[0009] The second member has a second surface opposite to the first surface and a second connecting portion formed on the second surface and connected to the first connecting portion.

[0010] One of the first connecting portion and the second connecting portion is formed of a protrusion, and the other is formed of a depression having a shape corresponding to the protrusion.

[0011] When the first component is viewed from the first surface, the front shape of the first connecting portion is a ring shape or a partially disconnected intermittent ring shape, and when the second component is viewed from the second surface, the front shape of the second connecting portion is a ring shape or a partially disconnected intermittent ring shape.

[0012] The stator of the present invention has:

[0013] The core of the present invention; and

[0014] The coil is arranged on each tooth portion of the core.

[0015] The rotating electric machine of the present invention is an axial gap type rotating electric machine in which a rotor and a stator are arranged in the axial direction of the rotating shaft of the rotor.

[0016] The stator is the stator of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a plan view of a stator included in the axial gap type rotating electrical machine shown in the first embodiment.

[0018] Figure 2 Yes means Figure 1 An oblique view of a portion of a stator.

[0019] Figure 3 yes Figure 2 Section view III-III.

[0020] Figure 4 yes Figure 1 A bottom view of a tooth portion of a stator.

[0021] Figure 5A yes Figure 4 V-V section view.

[0022] Figure 5B yes Figure 5A Magnified view of the circled portion in FIG.

[0023] Figure 6 yes Figure 4 VI-VI section view.

[0024] Figure 7 yes Figure 1 A top view of a yoke portion of a stator.

[0025] Fig. 8A yes Figure 7 Section view VIII-VIII of .

[0026] Figure 8B yes Fig. 8A Magnified view of the circled portion in FIG.

[0027] Fig. 9 yes Figure 7 IX-IX section view.

[0028] Fig.10 It is a partial vertical cross-sectional view of the axial gap type rotating electrical machine according to the first embodiment.

[0029] Fig.11 This is a partial cross-sectional view for explaining the connection state between the teeth portion and the yoke portion of the rotating electrical machine shown in the second embodiment.

[0030] Fig. 12A This is a partial cross-sectional view for explaining the connection state between the teeth portion and the yoke portion of the rotating electrical machine shown in the third embodiment.

[0031] Fig. 12B yes Fig. 12A Magnified view of the circled portion in FIG.

[0032] Fig.13A This is a partial cross-sectional view for explaining the connection state between the teeth portion and the yoke portion of the rotating electrical machine shown in the fourth embodiment.

[0033] Fig. 13B yes Fig.13A Magnified view of the circled portion in FIG.

[0034] Fig.14 This is a partial cross-sectional view for explaining the connection state between the teeth portion and the plate-like piece of the rotating electrical machine shown in the fifth embodiment.

[0035] Fig.15 This is a partial cross-sectional view for explaining the connection state between the teeth portion and the plate-like piece of the rotating electrical machine shown in the sixth embodiment. DETAILED DESCRIPTION

[0036] [Problems to be Solved by the Invention]

[0037] It is desired to improve the magnetic properties of the iron core and to increase the productivity of the iron core. For this reason, it is considered effective to make both the yoke and the tooth part consist of a high-density compressed powder molded body. In order to increase the density of the compressed powder molded body, it is necessary to compress and mold the soft magnetic powder by a high molding pressure (surface pressure). However, according to the research of the present inventors, it is known that in the yoke and the tooth part of the shape described in Patent Document 1, parts with low density are prone to appear locally. In addition, it is also known that the yoke and the tooth part of the shape described in Patent Document 1 cannot sometimes be completed by a single compression molding.

[0038] One object of the present invention is to provide an iron core of a powder compact having a high overall density and excellent productivity. Another object of the present invention is to provide a stator having the iron core. Another object of the present invention is to provide a rotating electric machine having the stator.

[0039] [Effects of the Invention]

[0040] The iron core of the present invention has high density as a whole and excellent productivity. In addition, the stator of the present invention has excellent magnetic properties and productivity. Furthermore, the rotating electric machine of the present invention has excellent output properties and productivity.

[0041] [Description of Embodiments of the Invention]

[0042] The present inventor studied the problem of forming a block-shaped tooth portion and a plate-shaped yoke portion respectively by a powder compact. As a result, it was found that the concave and convex portions connecting the tooth portion and the yoke portion were simple shapes as described in Patent Document 1, which would become a problem. In the case of making a tooth portion with a convex portion by compression molding, it is difficult for the soft magnetic powder to diffuse into the corner portion of the convex portion, and the density of the convex portion (especially the corner of the convex portion) is likely to be lower than other parts. If the density of the convex portion is low, the strength of the convex portion is reduced and the convex portion is easily damaged. Therefore, it may be impossible to connect the tooth portion and the yoke portion. In addition, in the case of making a yoke portion with a concave portion by compression molding, it is difficult for the soft magnetic powder to diffuse into the edge portion of the concave portion. Therefore, when making a yoke portion with a concave portion, after performing compression molding to form the overall shape of the yoke portion, compression molding for completing the concave portion must also be performed. That is, the yoke portion with a concave portion cannot be completed by a single compression molding. In view of these problems, the present inventor found that the above-mentioned problems can be solved by setting the shapes of the concave and convex portions to specific shapes.

[0043] Based on the above findings, embodiments of the present invention will be described below by way of examples.

[0044] <1> The iron core according to the embodiment is an iron core included in a rotor or a stator of an axial gap type rotating electrical machine.

[0045] The core has a block-shaped first component and a plate-shaped second component made of a powder compact.

[0046] The first member has a first surface opposite to the second member and a first connecting portion formed on the first surface.

[0047] The second member has a second surface opposite to the first surface and a second connecting portion formed on the second surface and connected to the first connecting portion.

[0048] One of the first connecting portion and the second connecting portion is formed by a protrusion, and the other is formed by a recess having a shape corresponding to the protrusion.

[0049] When the first component is viewed from the first surface, the front shape of the first connecting portion is a ring shape or a partially disconnected intermittent ring shape, and when the second component is viewed from the second surface, the front shape of the second connecting portion is a ring shape or a partially disconnected intermittent ring shape.

[0050] There is basically no part where the density of the soft magnetic powder is locally low in the above-mentioned iron core, so the above-mentioned iron core is high-density as a whole. The reason why the part with local low density is not formed in the iron core is that the front shape of the protrusion and the depression constituting the first connecting part and the second connecting part becomes a ring shape or a discontinuous ring shape (hereinafter, sometimes both the ring shape and the discontinuous ring shape are included and only the ring shape is expressed). If the protrusion is set to a ring shape, a height difference will appear between the protrusion and the inner and outer parts of the ring shape of the protrusion. Due to its height difference, during compression molding, it is easy for the soft magnetic powder to flow between the protrusion and the inner and outer parts lower than the protrusion. In addition, by setting the depression to a ring shape, a height difference will appear between the depression and the inner and outer parts of the ring shape of the depression. Due to its height difference, during compression molding, it is easy for the soft magnetic powder to flow between the depression and the inner and outer parts higher than the depression. If the fluidity of the soft magnetic powder in the peripheries of the projections and recesses is improved, it is possible to suppress a decrease in density in the peripheries.

[0051] The iron core has excellent productivity. The reason for this is that, as described above, the fluidity of the soft magnetic powder around the protrusions and depressions during compression molding of the iron core is high, and an iron core with a high overall density can be produced through a single compression molding. In addition, the fluidity of the soft magnetic powder is high, so the incidence of defective products having a locally low-density portion is reduced.

[0052] <2> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0053] The first component is a tooth portion,

[0054] The second component is a yoke.

[0055] By making the teeth and the yoke into separate parts, the mold for making the iron core can be made into a simple shape. Therefore, it is easy to make the density of the teeth and the yoke uniform. In addition, multiple teeth of the iron core can be made by one mold. Therefore, the productivity of the iron core can be improved.

[0056] <3> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0057] The first component is a toothed portion having a flange portion,

[0058] The second component is a yoke.

[0059] By providing the flange portion on the end surface of the tooth portion, the coil arranged on the tooth portion is less likely to fall off the tooth portion.

[0060] <4> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0061] The first component is an integrated part of a tooth part and a yoke part,

[0062] The second component is a plate-like piece separated from the yoke part,

[0063] The plate-like piece has a flange portion that is disposed on an end surface of the tooth portion on the opposite side to the yoke portion and extends from a contour line of the end surface.

[0064] By providing a flange portion on the end face of the tooth portion, the coil arranged on the tooth portion is not easy to fall off the tooth portion. By providing the plate-like piece including the flange portion and the tooth portion as separate parts, the flange portion can be formed after the coil is arranged on the tooth portion. Therefore, it is possible to facilitate the arrangement of the coil on the core.

[0065] <5> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0066] The first component is a tooth portion,

[0067] The second component is a yoke and a plate-like piece separated from the yoke.

[0068] The plate-like piece has a flange portion that is disposed on an end surface of the tooth portion on the opposite side to the yoke portion and extends from a contour line of the end surface.

[0069] This structure is a structure in which the teeth portion, the yoke portion, and the plate-like piece having the flange portion are separate bodies. With this structure, it is possible to suppress the density fluctuation of each component formed of the powder compact.

[0070] <6> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0071] The front shape of the first connection portion and the front shape of the second connection portion are non-annular shapes.

[0072] According to the above configuration, after the first member and the second member are coupled to each other, relative rotation of the two members on the first surface (second surface) can be suppressed.

[0073] <7> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0074] The junction between the bottom surface and the inner wall surface in the depression, and the junction between the inner wall surface and the first surface or the second surface are rounded.

[0075] The joints between the top surface and the outer wall surface of the protrusion, and the joints between the outer wall surface and the first surface or the second surface are rounded.

[0076] By rounding the corners of the joints, the fluidity of the soft magnetic powder in the vicinity of the projections and recesses during compression molding can be improved.

[0077] <8> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0078] The depth of the depression and the height of the projection are greater than or equal to 0.5 mm and less than or equal to 30% of the thickness of the smaller one of the first member and the second member.

[0079] By setting the depth of the concave and the height of the convex to be greater than or equal to 0.5 mm, the connection strength between the convex and the concave can be sufficiently ensured. In addition, by setting the depth of the concave and the height of the convex to be less than or equal to 30% of the thickness of the smaller one of the first component and the second component, the decrease in the fluidity of the soft magnetic powder during compression molding and the load on the mold can be suppressed.

[0080] <9> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0081] The width of the depression and the width of the protrusion are greater than or equal to 0.5 mm and less than or equal to 10 mm.

[0082] By setting the width of the concave and the width of the convex to be greater than or equal to 0.5 mm, the connection strength between the convex and the concave can be sufficiently ensured. In particular, by setting the width of the convex to be greater than or equal to 1.0 mm, the mechanical strength of the convex can be sufficiently ensured. In addition, by setting the width of the concave and the width of the convex to be less than or equal to 10 mm, the decrease in the fluidity of the soft magnetic powder during compression molding can be suppressed.

[0083] <10> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0084] The junction between the bottom surface and the inner wall surface in the recess, and the junction between the inner wall surface and the first surface or the second surface are rounded, and

[0085] The junction between the top surface and the outer wall surface of the protrusion, and the junction between the outer wall surface and the first surface or the second surface are rounded.

[0086] The radius of curvature of the fillet of each joint is greater than or equal to 0.5 mm and less than or equal to 4.0 mm.

[0087] By rounding the joints between the surfaces of the projections and the depressions, the fluidity of the soft magnetic powder during compression molding of the first component and the second component is improved. As a result, it is less likely that a portion with a locally low density will appear in the first component and the second component. In particular, by setting the radius of curvature of the fillet at the joint to be greater than or equal to 0.5 mm and less than or equal to 4.0 mm, the above-mentioned fluidity can be easily improved.

[0088] <11> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0089] The first connecting portion is a depression, and the second connecting portion is a protrusion.

[0090] The second member forming the second connection portion is plate-shaped. Therefore, by providing the second connection portion as a projection, the mechanical strength of the entire second member can be improved.

[0091] <12> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0092] The first connecting portion is a protrusion, and the second connecting portion is a depression.

[0093] The second member forming the second connection portion is plate-shaped. Therefore, by making the second connection portion concave, the assembly workability is improved when the first member and the second member are bonded together.

[0094] <13> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0095] The front shape of the first connecting portion and the front shape of the second connecting portion are a racetrack shape, or any shape selected from a triangle, a rectangle, a trapezoid, and a rhombus with rounded corners at each vertex.

[0096] If the above shape is adopted, the front shape of the first connecting part and the second connecting part will not become too complicated. Therefore, the mechanical strength of the first connecting part and the second connecting part is not easy to be reduced. In addition, the above structure also has the following advantage, that is, it is easy to make a mold for making the first component and the second component.

[0097] <14> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0098] When the area of ​​the first surface is set to 100%, the area inside the outer peripheral contour line of the first connecting portion is greater than or equal to 10% and less than or equal to 80%.

[0099] When the area of ​​the second surface is 100%, the area inside the outer peripheral contour of the second connecting portion is greater than or equal to 10% and less than or equal to 80%.

[0100] The area of ​​the first surface (second surface) is the plane area of ​​the first surface (second surface) when the first surface (second surface) is viewed from the orthogonal direction. That is, the area of ​​the first surface (second surface) also includes the area inside the outer peripheral contour line of the first connecting portion (second connecting portion). According to the above structure, the connection between the first component having the first connecting portion and the second component having the second connecting portion can be made firm.

[0101] <15> As one aspect of the core according to the embodiment, the following aspects can be cited:

[0102] The first member has a third connection portion formed inside the ring shape of the first connection portion on the first surface,

[0103] The second member has a fourth connection portion formed inside the ring shape of the second connection portion on the second surface,

[0104] The third connection portion has a shape that is convex or concave relative to the first surface and on the opposite side of the first connection portion.

[0105] The fourth connection portion has a shape corresponding to the third connection portion.

[0106] By connecting the third connection portion and the fourth connection portion in addition to the connection between the first connection portion and the second connection portion, the first member and the second member can be more firmly connected.

[0107] <16> A stator according to an embodiment includes:

[0108] The core according to any one of <1> to <15> above; and

[0109] The coil is arranged on each tooth portion of the core.

[0110] The stator has excellent magnetic properties. This is because the iron core of the stator is a high-density iron core involved in the embodiment. In addition, the stator has excellent productivity. This is because the iron core of the stator is an iron core with excellent productivity involved in the embodiment.

[0111] <17> The rotating electrical machine according to the embodiment is an axial gap type rotating electrical machine in which a rotor and a stator are arranged in the axial direction of a rotating shaft of the rotor.

[0112] This is the stator of <16> mentioned above.

[0113] The above-mentioned rotating electric machine has excellent output characteristics. This is because the stator of the rotating electric machine is a stator with excellent magnetic characteristics. In addition, the above-mentioned rotating electric machine has excellent productivity. This is because the stator of the rotating electric machine is a stator with excellent productivity.

[0114] [Details of the embodiments of the present invention]

[0115] Based on the accompanying drawings, specific examples of the core, stator and rotating electrical machine involved in the embodiments of the present invention are described. The same reference numerals in the figures represent the same or equivalent parts. In addition, the present invention is not limited to these examples, but is shown by the claims, including the contents equivalent to the claims and all changes within the scope thereof.

[0116] <Implementation method 1>

[0117] 《Rotating Electric Machines》

[0118] In implementation mode 1, Fig.10 The axial gap type rotating electrical machine 1 shown in the figure is described as an example. The rotating electrical machine 1 may be a generator or a motor. The rotating electrical machine 1 includes a rotor 2 and a stator 3 which are arranged in a housing 10 .

[0119] Rotor

[0120] The rotor 2 has a plurality of flat-plate-shaped magnets 22 and a ring-shaped retaining plate 21 that supports the magnets 22. The retaining plate 21 is fixed to the shaft 20 and rotates together with the shaft 20. The magnets 22 are embedded in the retaining plate 21. The magnets 22 are arranged at intervals in the circumferential direction of the shaft 20. In addition, the magnets 22 are magnetized in the direction of the rotation axis of the rotor 2 (the axial direction of the shaft 20). The magnetization directions of the magnets 22 adjacent to each other in the circumferential direction of the shaft 20 are opposite to each other.

[0121] ·stator

[0122] The stator 3 has an iron core 30 and a coil 31 arranged on the teeth 4 of the iron core 30. The stator 3 is arranged opposite to the rotor 2 in the axial direction of the shaft 20 and is fixed to the housing 10. A bearing 23 is arranged between the stator 3 and the shaft 20, and the stator 3 does not rotate. The rotating electric machine 1 of this embodiment has a feature in the stator 3, particularly the iron core 30 of the stator 3.

[0123] Iron Core

[0124] Figures 1 to 3The iron core 30 shown has teeth 4 and yoke 5. In this example, 12 teeth 4 are formed in the iron core 30. The number of teeth 4 is not particularly limited. In the case of an axial gap type rotating electrical machine 1, a magnetic circuit is formed through the yoke 5 by two adjacent teeth 4, so the number of teeth 4 is preferably set to 2n (n is a natural number). In this example, the teeth 4 are set as a first block-shaped component, the yoke 5 is set as a second plate-shaped component, and the teeth 4 and the yoke 5 are manufactured separately. The separately manufactured teeth 4 and yoke 5 are made by Figure 3 The connection mechanism 9 shown is connected. The details of the connection mechanism 9 will be described later.

[0125] ·Gear

[0126] When describing the tooth portion (first member) 4, reference will be made mainly to Figure 4 , 5A , 5B, 6. The tooth portion 4 of this example is in contact with the yoke portion 5 ( Figure 3 ) is a roughly trapezoidal columnar component having a flange (flange portion 45) at the end on the opposite side. The shape of the tooth portion 4 is not particularly limited. For example, the tooth portion 4 can be roughly triangular prism-shaped. In addition, the shape of the tooth portion 4 can also be cylindrical, quadrangular prism-shaped, etc.

[0127] The tooth portion 4 has a first surface 40, a peripheral surface 41 and an end surface 42. The first surface 40 is a flat surface and is aligned with the yoke portion 5 ( Figure 3 ) is the lower surface of the tooth portion 4 opposite to the first surface 40. The end surface 42 is the upper surface of the tooth portion 4 on the opposite side to the first surface 40. The peripheral surface 41 is a surface connecting the first surface 40 and the end surface 42. A first connecting portion 91 of the connecting mechanism 9 described later is formed on the first surface 40 of the tooth portion 4.

[0128] The flange portion 45 of the tooth portion 4 may be omitted. Fig.10 ), a large relative area of ​​the tooth portion 4 relative to the rotor 2 is advantageous for improving performance. Therefore, at the end of the tooth portion 4 on the opposite side to the yoke portion 5 in this example, a flange portion 45 extending in a direction orthogonal to the protruding direction of the tooth portion 4 is formed. The outer peripheral contour line of the flange portion 45 in this example is roughly similar to the outer peripheral contour line of the first surface 40. The flange portion 45 also has the following function, namely, to prevent the coil 31 arranged on the tooth portion 4 from falling off from the tooth portion 4.

[0129] The tooth portion 4 is a powder compact formed by compression molding of soft magnetic powder. Soft magnetic powder is an aggregate of soft magnetic particles. Examples of soft magnetic powder include pure iron (purity greater than or equal to 99% by mass) and at least one powder selected from iron-based alloys such as Fe-Si-Al alloys (send silicon aluminum), Fe-Si alloys (silicon steel), Fe-Al alloys, and Fe-Ni alloys (Permalloy). The soft magnetic particles preferably have an insulating coating on their surface. An insulating coating is formed on the surface of the soft magnetic particles, thereby ensuring electrical insulation between the soft magnetic particles. Therefore, the iron loss of the tooth portion 4 caused by eddy current loss can be reduced. Examples of the insulating coating include a phosphate coating, a silica coating, and the like.

[0130] The average particle size of the soft magnetic particles can be set to be greater than or equal to 10μm and less than or equal to 300μm. By setting the average particle size of the soft magnetic particles to be greater than or equal to 10μm, the fluidity of the soft magnetic powder will not be reduced, and the increase in the coercive force and hysteresis loss of the powder compact can be suppressed. On the contrary, by setting the average particle size of the soft magnetic particles to be less than or equal to 300μm, the eddy current loss of the powder compact occurring in the high frequency band can be effectively reduced. The more preferred average particle size of the soft magnetic particles is greater than or equal to 40μm and less than or equal to 260μm. Here, the average particle size refers to the particle size of the particles whose sum of mass from particles with a small particle size reaches 50% of the total mass in the histogram of the particle size, that is, the 50% particle size.

[0131] The relative density of the powder compact is preferably greater than or equal to 90%, and the magnetic properties of the powder compact can be improved by high density. The more preferred relative density is greater than or equal to 93%. The relative density refers to the ratio (%) of the density of the powder compact to the true density of the powder compact (soft magnetic powder).

[0132] ·Yoke

[0133] When describing the yoke 5, reference is mainly made to Figure 7 , 8A , 8B, 9. Figure 7 As shown, the yoke 5 is a ring-shaped component. The yoke 5 of this example is composed of one component. The yoke 5 can also be composed of a plurality of split pieces. For example, the ring-shaped yoke 5 can be formed by connecting and combining fan-shaped split pieces.

[0134] The yoke 5 has a second surface 50, a back surface 52, an inner edge surface 53, and an outer edge surface 54. The second surface 50 is Figure 3The second surface 50 is a flat surface parallel to the first surface 40. Therefore, the entire first surface 40 of the tooth portion 4 is in surface contact with the second surface 50. The back surface 52 of the yoke 5 is the lower surface of the yoke 5 parallel to the second surface 50. The edge surface 53 is a surface connecting the second surface 50 and the back surface 52 on the inner side of the ring of the yoke 5. On the inner side of the edge surface 53, a groove is formed to allow the shaft 20 ( Fig.10 ) through a through hole 55. The edge surface 54 is a surface connecting the second surface 50 and the back surface 52 on the outer side of the ring of the yoke 5. The second surface 50 of the yoke 5 is formed with a second connection portion 92 of the connection mechanism 9 described later.

[0135] The yoke 5 is formed of a powder compact similar to the tooth 4. The composition of the powder compact constituting the yoke 5 may be the same as or different from that of the powder compact constituting the tooth 4. In addition, the density of the yoke 5 may be the same as or different from that of the tooth 4.

[0136] ·Connection mechanism

[0137] The connecting mechanism 9 includes a first connecting portion 91 and a second connecting portion 92. The first connecting portion 91 is a depression formed on the first surface 40, and the second connecting portion 92 is a protrusion protruding from the second surface 50. The inside of the first connecting portion 91 (depression) is formed into a shape corresponding to the outer shape of the second connecting portion 92 (protrusion). Therefore, by embedding the second connecting portion 92 into the first connecting portion 91, the outer peripheral surface of the second connecting portion 92 is in surface contact with the inner peripheral surface of the first connecting portion 91. As a result, the tooth portion 4 and the yoke portion 5 are connected.

[0138] ··First connecting part

[0139] based on Figure 4 , 5A 5B, the shape of the first connecting portion 91 (recess) is described in detail. Figure 4 As shown, when the tooth portion 4 is observed from the first surface 40, the front shape of the first connecting portion 91 becomes a ring shape. The front shape of the first connecting portion 91 in this example becomes a runway shape. The front shape of the first connecting portion 91 can be a circular ring shape, or a non-circular ring shape including the runway shape of this example. As non-circular ring shapes other than the runway shape, for example, there can be cited triangles with rounded corners at each vertex, rectangles (including squares), trapezoids, rhombuses and other polygonal shapes, C-shapes in which part of the ring is not connected, U-shapes and other discontinuous ring shapes. If the front shape of the first connecting portion 91 is a non-circular ring shape, after the tooth portion 4 and the yoke portion 5 are connected, it is possible to suppress the tooth portion 4 from rotating relative to the yoke portion 5 on the first surface 40 (second surface 50). Figure 4 Different from the example shown in FIG. 1 , the first connecting portion 91 is divided into the yoke portion 5 ( Figure 1 ) in the radial direction, separated by a dividing line (refer to Figure 4 The upper and lower parts of the paper surface of the double dotted line can be set as non-line symmetry. In this case, the direction of the tooth portion 4 relative to the yoke portion 5 is limited, so the direction of the tooth portion 4 will not be mistaken.

[0140] The inner side of the ring shape of the first connection portion 91 (recess) is at the same height as the first surface 40. Unlike this example, the inner side of the ring shape of the first connection portion 91 may be recessed relative to the first surface 40 or may be protruding from the first surface 40 as in Embodiment 3 described later.

[0141] In this example, the number of first connection parts 91 in the tooth part 4 is one. A plurality of first connection parts 91 may be provided in one tooth part 4. When a plurality of first connection parts 91 are formed, some may be recessed and the remaining may be raised.

[0142] The width of the first connecting portion 91 (recess) in this example is as follows Figure 5B As shown, it gradually narrows toward the depth direction. That is, the width of the bottom surface 9d of the first connecting portion 91 is narrower than the width of the opening of the first connecting portion 91. In addition, the inner wall surface 9i is inclined in the direction of expansion from the bottom surface 9d toward the opening. The depression of the shape described above helps to improve the fluidity of the soft magnetic powder during compression molding. Of course, the width of the depression in the depth direction can also be the same. Here, the width of the first connecting portion 91 is the circumferential direction ( Figure 5B The length in a direction perpendicular to the paper thickness direction).

[0143] The joint between the bottom surface 9d and the inner wall surface 9i in the first connecting portion 91 (recess) is rounded. In addition, the joint between the inner wall surface 9i and the first surface 40 is also rounded. By setting the two joints as rounded corners, the fluidity of the soft magnetic powder during compression molding can be improved. For example, the radius of curvature of the fillet can be set to be greater than or equal to 0.5 mm and less than or equal to 4.0 mm. A more preferred radius of curvature is greater than or equal to 1.0 mm and less than or equal to 3.0 mm.

[0144] The width w1 of the first connecting portion 91 (depression) is preferably set to be greater than or equal to 0.5 mm and less than or equal to 10 mm. The width w1 is the width of the opening of the depression. By setting the width w1 to be greater than or equal to 0.5 mm, the connection strength of the first connecting portion 91 (depression) and the second connecting portion 92 (protrusion) can be fully ensured. In addition, by setting the width w1 to be less than or equal to 10 mm, the fluidity of the soft magnetic powder during compression molding can be suppressed. A more preferred width w1 is greater than or equal to 0.5 mm and less than or equal to 4 mm, and a more preferred width w1 is greater than or equal to 1.0 mm and less than or equal to 3.0 mm.

[0145] The depth d1 of the first connecting portion 91 (depression) is preferably set to be greater than or equal to 0.5 mm and less than or equal to 30% of the thickness of the first component and the second component with a smaller thickness (in this case, the yoke 5). The depth d1 is the length of the vertical line from the first surface 40 to the bottom surface 9d. By setting the depth d1 to be greater than or equal to 0.5 mm, the connection strength of the first connecting portion 91 (depression) and the second connecting portion 92 (protrusion) can be fully ensured. In addition, by setting the depth d1 to be less than or equal to 30% of the thickness of the yoke 5, the fluidity of the soft magnetic powder during compression molding can be suppressed. A more preferred depth d1 is greater than or equal to 1.0 mm and less than or equal to 25% of the thickness of the first component and the second component with a smaller thickness.

[0146] The outer peripheral contour line of the first connecting portion 91 on the first surface 40 (see Figure 4 ) can be appropriately selected. For example, when the area of ​​the first surface 40 is set to 100%, the area inside the outer peripheral contour line of the first connecting portion 91 can be set to be greater than or equal to 10% and less than or equal to 80%. By setting the area ratio of the outer shape of the first connecting portion 91 to the first surface 40 to be greater than or equal to 10% and less than or equal to 80%, the connection between the tooth portion 4 and the yoke portion 5 can be made firm. A more preferred area ratio is greater than or equal to 20% and less than or equal to 70%.

[0147] ··Second connection part

[0148] based on Figure 7 8, the shape of the second connecting portion 92 (protrusion) is described in detail. As already described, the second connecting portion 92 has a shape corresponding to the first connecting portion 91. Therefore, Figure 7 As shown, when the yoke 5 is viewed from the second surface 50 , the front shape of the second connection portion 92 is the same shape and the same size as the front shape of the first connection portion 91 .

[0149] The inner side of the ring shape of the second connection portion 92 (protrusion) is at the same height as the second surface 50. Unlike this example, the inner side of the ring shape of the second connection portion 92 may be more protruding than the second surface 50, or may be more recessed than the second surface 50 as in Embodiment 4 described later.

[0150] The width of the second connecting portion 92 (protrusion) in this example is as follows Figure 8BAs shown, it gradually becomes thinner as it goes toward the top surface 9t. That is, the width of the top surface 9t of the second connecting portion 92 is narrower than the width of the root of the second connecting portion 92. In addition, the outer wall surface 9o is inclined in a direction that becomes narrower as it goes from the root toward the top surface 9t. The protrusion of the shape as described above helps to improve the fluidity of the soft magnetic powder during compression molding. Here, the width of the second connecting portion 92 is the circumferential direction ( Figure 8B The length is perpendicular to the paper thickness direction).

[0151] The joints between the top surface 9t and the outer wall surface 9o in the second connecting portion 92 (protrusion) and the joints between the outer wall surface 9o and the second surface 50 are rounded to match the shape of the first connecting portion 91 (recess). By rounding the two joints of the protrusion, the fluidity of the soft magnetic powder during compression molding can be improved.

[0152] The width w2 of the second connecting portion 92 (protrusion) is Figure 5B The width w1 of the first connecting portion 91 (recess) is the same as that of the second connecting portion 92 (protrusion). The width w2 is the width of the root of the protrusion. Figure 5B The depth d1 of the first connecting portion 91 (recess) is the same. The height h2 is the length of the perpendicular line from the extension of the top surface 9t to the second surface 50. The limitation of the width w2 and height h2 of the protrusion helps to improve the mechanical strength of the protrusion. In addition, the limitation of the width w2 and height h2 of the protrusion helps to improve the fluidity of the soft magnetic powder near the protrusion during compression molding.

[0153] <<Effects of the present embodiment>>

[0154] In the embodiment, the core 30 ( Figure 1 ) has basically no portion where the density of the soft magnetic powder is locally low, so the core 30 has a high density as a whole. The portion where the density is locally low is not formed in the core 30 because the front shape of the protrusions and recesses constituting the first connecting portion 91 and the second connecting portion 92 is a ring shape or a discontinuous ring shape.

[0155] The iron core 30 of the embodiment has excellent productivity. This is because the soft magnetic powder around the protrusions and depressions during compression molding of the iron core 30 has high fluidity, and the iron core 30 with an overall high density can be manufactured through a single compression molding. In addition, the high fluidity of the soft magnetic powder reduces the incidence of defective products having a local low-density portion, which is also a factor in improving the productivity of the iron core 30.

[0156] In this example, the tooth portion 4 and the yoke portion 5 are provided as separate parts. Therefore, the mold for manufacturing the iron core 30 can be provided with a simple shape. As a result, it is easy to make the density of the tooth portion 4 and the yoke portion 5 uniform. In addition, a plurality of tooth portions 4 of the iron core 30 can be manufactured by one mold. As a result, the productivity of the iron core 30 can be improved.

[0157] In this example, the second connection portion 92 formed on the yoke 5 is formed as a projection. Therefore, it is possible to suppress a decrease in the mechanical strength of the yoke 5 due to the provision of the second connection portion 92.

[0158] The stator 3 ( Fig.10 ) has excellent magnetic properties. This is because the density of the magnetic powder of the stator 3 is high. In addition, the productivity of the stator 3 is excellent. This is because the productivity of the iron core 30 of the stator 3 is high.

[0159] The rotating electrical machine 1 having the stator 3 of the above-described embodiment has excellent output characteristics. This is because the stator 3 of the rotating electrical machine 1 has high magnetic characteristics. In addition, the rotating electrical machine 1 has excellent productivity. This is because the stator 3 of the rotating electrical machine 1 has high productivity.

[0160] <Implementation method 2>

[0161] In implementation mode 2, based on Fig.11 An iron core 30 which is different from that in the first embodiment will be described. Fig.11 The observation method and implementation method 1 Figure 3 same.

[0162] exist Fig.11 In the core 30 of the embodiment, the first connection portion 91 of the tooth portion 4 is a projection, and the second connection portion 92 of the yoke portion 5 is a recess. The shape and size of the projection and the recess can be the same as those in Embodiment 1. According to the structure of this example, the same effect as that of Embodiment 1 can also be obtained.

[0163] <Implementation method 3>

[0164] In implementation mode 3, based on Fig. 12A , 12B The core 30 in which the teeth portion 4 has the third connection portion 93 and the yoke portion 5 has the fourth connection portion 94 will be described.

[0165] The third connection portion 93 is formed inside the ring shape of the first connection portion 91 in the first surface 40, and is a protrusion protruding from the first surface 40. The height h3 of the third connection portion 93 of this example is greater than the height h2 of the second connection portion 92 (protrusion). The height h3 of the third connection portion 93 is the length of a perpendicular line from the first surface 40 to the top surface of the protrusion. The preferred range of the height h3 is the same as the preferred range of the height h2.

[0166] like Fig. 12A As shown in FIG. 1 , the fourth connecting portion 94 is formed inside the ring shape of the second connecting portion 92 in the second surface 50 and is a depression lower than the second surface 50. The inner shape of the fourth connecting portion 94 (depression) has a shape corresponding to the outer shape of the third connecting portion 93 (protrusion). Fig. 12B As shown, the depth d4 of the fourth connection portion 94 (recess) of this example is the same as the height h3 of the third connection portion 93 (protrusion).

[0167] According to the structure of this example, compared with the iron core 30 of Embodiments 1 and 2, the teeth portion 4 and the yoke portion 5 can be connected more firmly.

[0168] <Implementation method 4>

[0169] In implementation mode 4, based on Fig.13A , 13B An iron core 30 which is different from that in the third embodiment will be described.

[0170] like Fig.13A As shown, the third connection portion 93 of this example is a recess formed inside the ring shape of the first connection portion 91 on the first surface 40 . On the other hand, the fourth connection portion 94 is a projection formed inside the ring shape of the second connection portion 92 on the second surface 50 .

[0171] In this example, the inner shape of the third connecting portion 93 (recess) has a shape corresponding to the outer shape of the fourth connecting portion 94 (protrusion). Fig. 13B As shown, the depth d3 of the third connection portion 93 of this example is the same as the height h4 of the fourth connection portion 94 .

[0172] <Implementation method 5>

[0173] In implementation mode 5, based on Fig.14 The core 30 formed by connecting the teeth portion 4 and the plate-like piece 6 disposed on the opposite side of the yoke portion 5 in the teeth portion 4 will be described.

[0174] The teeth 4 and yoke 5 of this example are formed integrally. The teeth 4 and yoke 5 may be separate bodies as in the core 30 of Embodiments 1 to 4. In this case, although the number of components constituting the core 30 increases, it is easy to make the density of the entire core 30 uniform.

[0175] The plate-like piece 6 is provided on the end face 42 of the tooth portion 4 on the opposite side to the yoke portion. The plate-like piece 6 is made separately from the tooth portion 4 and connected to the tooth portion 4. That is, the tooth portion 4 is the first component and the plate-like piece 6 is the second component. In addition, the end face 42 of the tooth portion 4 (first component) is also the first face 40 opposite to the plate-like piece 6 (second component). The opposite face 60 of the plate-like piece 6 opposite to the first face 40 is the second face 50.

[0176] A first connection portion 91 composed of an annular depression is formed on the first surface 40 of the tooth portion 4. Also, a second connection portion 92 composed of an annular projection is formed on the second surface 50 of the plate-like piece 6.

[0177] According to the structure of this example, it is possible to Fig.10 ) is arranged on the tooth portion 4, and then the flange portion 45 is formed on the tooth portion 4. In this case, the arrangement of the coil 31 becomes very easy.

[0178] <Implementation method 6>

[0179] In the sixth embodiment, the plate-like piece 6 is provided on the opposite side of the tooth portion 4 from the yoke portion 5. Fig.15 An iron core 30 which is different from that in the fifth embodiment will be described.

[0180] In this example, a first connecting portion 91 composed of a ring-shaped protrusion is formed on the first surface 40 of the tooth portion 4. In addition, a second connecting portion 92 composed of a ring-shaped recess is formed on the second surface 50 of the plate-like piece 6. According to the structure of this example, it is also possible to Fig.10 ) is arranged on the tooth portion 4, and then a flange portion 45 is formed on the tooth portion 4.

[0181] <Implementation method 7>

[0182] The iron core 30 described in Embodiments 1 to 6 is used in a stator. This iron core can also be used in a rotor.

[0183] Description of the label

[0184] 1 Rotating motor

[0185] 10 Shell

[0186] 2 rotors

[0187] 20 shaft, 21 retaining plate, 22 magnet, 23 bearing

[0188] 3. Stator

[0189] 30 core, 31 coil

[0190] 4. Tooth part (first component)

[0191] 40 first surface, 41 peripheral surface, 42 end surface, 45 flange portion

[0192] 5Yoke (second component)

[0193] 50 second surface, 52 back surface, 53 inner edge surface, 54 outer edge surface, 55 through hole

[0194] 6 Plate-like piece (second component)

[0195] 60 Opposite side

[0196] 9 Linkage

[0197] 91 first connecting portion, 92 second connecting portion, 93 third connecting portion, 94 fourth connecting portion

[0198] 9d bottom surface, 9i inner wall surface, 9o outer wall surface, 9t top surface

Claims

1. An iron core, which is an iron core of a rotor or a stator of an axial gap type rotating electric machine, The core has a block-shaped first component and a plate-shaped second component made of a powder compact. The first member has a first surface opposite to the second member and a first connecting portion formed on the first surface. The second member has a second surface opposite to the first surface and a second connecting portion formed on the second surface and connected to the first connecting portion. One of the first connecting portion and the second connecting portion is formed of a protrusion, and the other is formed of a depression having a shape corresponding to the protrusion. When the first component is viewed from the first surface, the front shape of the first connecting portion is a ring shape or a partially disconnected intermittent ring shape, and when the second component is viewed from the second surface, the front shape of the second connecting portion is a ring shape or a partially disconnected intermittent ring shape.

2. The core according to claim 1, wherein: The first component is a tooth portion, The second component is a yoke.

3. The core according to claim 1, wherein: The first component is a toothed portion having a flange portion, The second component is a yoke.

4. The core according to claim 1, wherein: The first component is an integrated part of a tooth part and a yoke part, The second component is a plate-like piece separated from the yoke part, The plate-like piece has a flange portion that is disposed on an end surface of the tooth portion on the opposite side to the yoke portion and extends from a contour line of the end surface.

5. The core according to claim 1, wherein: The first component is a tooth portion, The second component is a yoke and a plate-like piece separated from the yoke. The plate-like piece has a flange portion that is disposed on an end surface of the tooth portion on the opposite side to the yoke portion and extends from a contour line of the end surface.

6. The core according to any one of claims 1 to 5, wherein: The front shape of the first connection portion and the front shape of the second connection portion are non-annular shapes.

7. The core according to any one of claims 1 to 5, wherein: The junction between the bottom surface and the inner wall surface in the depression, and the junction between the inner wall surface and the first surface or the second surface are rounded. The joints between the top surface and the outer wall surface of the protrusion, and the joints between the outer wall surface and the first surface or the second surface are rounded.

8. The core according to any one of claims 1 to 5, wherein: The depth of the depression and the height of the projection are greater than or equal to 0.5 mm and less than or equal to 30% of the thickness of the smaller one of the first member and the second member.

9. The core according to any one of claims 1 to 5, wherein: The width of the depression and the width of the protrusion are greater than or equal to 0.5 mm and less than or equal to 10 mm.

10. The core according to any one of claims 1 to 5, wherein: The junction between the bottom surface and the inner wall surface in the recess, and the junction between the inner wall surface and the first surface or the second surface are rounded, and The junction between the top surface and the outer wall surface of the protrusion, and the junction between the outer wall surface and the first surface or the second surface are rounded. The radius of curvature of the rounded corners of each joint is greater than or equal to 0.5 mm and less than or equal to 4.0 mm.

11. The core according to any one of claims 1 to 5, wherein: The first connecting portion is a depression, and the second connecting portion is a protrusion.

12. The core according to any one of claims 1 to 5, wherein: The first connecting portion is a protrusion, and the second connecting portion is a depression.

13. The core according to any one of claims 1 to 5, wherein: The front shape of the first connecting portion and the front shape of the second connecting portion are a racetrack shape, or any shape selected from a triangle, a rectangle, a trapezoid, and a rhombus with rounded corners at each vertex.

14. The core according to any one of claims 1 to 5, wherein: When the area of ​​the first surface is set to 100%, the area inside the outer peripheral contour line of the first connecting portion is greater than or equal to 10% and less than or equal to 80%. When the area of ​​the second surface is 100%, the area inside the outer peripheral contour of the second connecting portion is greater than or equal to 10% and less than or equal to 80%.

15. The core according to any one of claims 1 to 5, wherein: The first member has a third connection portion formed inside the ring shape of the first connection portion on the first surface, The second member has a fourth connection portion formed inside the ring shape of the second connection portion on the second surface, The third connection portion has a shape that is convex or concave relative to the first surface and on the opposite side of the first connection portion. The fourth connection portion has a shape corresponding to the third connection portion.

16. A stator, comprising: The iron core according to any one of claims 1 to 15; and The coil is arranged on each tooth portion of the core.

17. A rotating electrical machine, which is an axial gap type rotating electrical machine in which a rotor and a stator are arranged in the axial direction of a rotating shaft of the rotor, The stator is the stator according to claim 16.

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