Core piece, stator core, stator, rotary electric machine, and method for manufacturing core piece

Abstract

A kind of iron core piece, wherein, cylindrical first component and plate-like second component are made of powder compact of integrated molding, powder compact has multiple soft magnetic particles of flat shape, in the first section of first component, the first average aspect ratio of soft magnetic particle is 1.2 or more, in the second section of second component, the second average aspect ratio of soft magnetic particle is 1.2 or more, first average aspect ratio is the ratio L12 / L11 of average length L11 and average length L12 of first section, second average aspect ratio is the ratio L22 / L21 of average length L21 and average length L22 of second section, average length L11 is the average of the length of soft magnetic particle along the radial direction of stator core, average length L12 is the average of the length of soft magnetic particle along the axial direction of stator core, average length L21 is the average of the length of soft magnetic particle along the radial direction of stator core, average length L22 is the average of the length of soft magnetic particle along the circumferential direction of stator core.

Description

Technical Field

[0001] This invention relates to iron chip, stator core, stator, rotating electric motor, and a method for manufacturing iron chip.

[0002] This application claims priority based on Japanese Patent Application No. 2020-082831 filed on May 8, 2020, and incorporates all the contents set forth in the aforementioned Japanese application. Background Technology

[0003] Patent document 1 discloses a stator core for an axially spaced motor. The stator core has a yoke and teeth.

[0004] Patent Document 1: Japanese Patent Application Publication No. 2009-44829 Summary of the Invention

[0005] The present invention relates to a stator core of a rotary motor in which the iron chip is configured in a ring shape to form an axially spaced type. The iron chip has: a columnar first component extending axially in the stator core; and a plate-shaped second component disposed at a first end of the first component in the axial direction of the stator core. The first and second components are integrally formed from a pressed powder molded body, which has a plurality of soft magnetic particles. The soft magnetic particles are flat in shape. In a first cross-section of the first component along the axial and radial directions of the stator core, the first average aspect ratio of the soft magnetic particles is 1.2 or more. In a second cross-section of the second component orthogonal to the axial direction of the stator core, the soft magnetic particles... The second average aspect ratio is 1.2 or higher. The first average aspect ratio is the ratio of the average length L11 to the average length L12 of the first cross-section, L12 / L11. The second average aspect ratio is the ratio of the average length L21 to the average length L22 of the second cross-section, L22 / L21. The average length L11 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L12 is the average length of the soft magnetic particles along the axial direction of the stator core. The average length L21 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L22 is the average length of the soft magnetic particles along the circumferential direction of the stator core.

[0006] The stator core involved in this invention is a stator core of an axially spaced rotary motor. The stator core has a plurality of iron chips arranged in a ring shape, each of which is the iron chip involved in this invention.

[0007] The stator involved in this invention is an axially gap type rotary motor stator, which has a stator core as involved in this invention and coils disposed in each of the first components of the stator core.

[0008] The rotary motor involved in this invention is an axial clearance type rotary motor having a rotor and a stator, wherein the stator is the stator involved in this invention.

[0009] The present invention relates to a method for manufacturing an iron chip, which is a stator core of a rotary motor configured in an annular shape and having an axial gap type. The method comprises the following steps: filling a mold with raw material powder containing a plurality of soft magnetic particles in a spherical shape; and compressing the raw material powder within the mold to form a molded body. The iron chip has: a columnar first component extending axially in the stator core; and a plate-shaped second component disposed at a first end of the first component in the axial direction of the stator core. The direction of compression of the raw material powder is radial along the stator core. Attached Figure Description

[0010] Figure 1 This is a perspective view showing the iron chip involved in Embodiment 1.

[0011] Figure 2 This is a schematic top view showing the iron chip involved in Embodiment 1.

[0012] Figure 3 This is a diagram showing the iron chip involved in Embodiment 1 as viewed from the inner circumferential side.

[0013] Figure 4 yes Figure 3 The image shows a cross-sectional view of the iron chip (IV-IV).

[0014] Figure 5 yes Figure 3 The image shows a V-V cross-sectional view of the iron chip.

[0015] Figure 6 yes Figure 3 The VI-VI cross-sectional view of the iron chip shown.

[0016] Figure 7 yes Figure 2 The iron chip shown is shown in sectional view VII-VII.

[0017] Figure 8 It means Figure 7 A rough enlarged view of the area within the dashed circle.

[0018] Figure 9 It means Figure 5 A rough enlarged view of the area within the dashed circle.

[0019] Figure 10 yes Figure 2 The X-X cross-sectional view of the iron chip shown.

[0020] Figure 11 This is a top view showing the opening edge of the die of the mold used to manufacture the iron chip according to Embodiment 1.

[0021] Figure 12 This is a schematic cross-sectional view of the mold used to manufacture the first component of the iron chip according to Embodiment 1.

[0022] Figure 13 This is a schematic cross-sectional view of a mold used to manufacture the second component of the iron chip according to Embodiment 1.

[0023] Figure 14 This is a schematic cross-sectional view of the mold used to manufacture the third component of the iron chip according to Embodiment 1.

[0024] Figure 15 This is a perspective view showing the iron chip involved in Embodiment 2.

[0025] Figure 16 This is a schematic perspective view of the stator core involved in Embodiment 3.

[0026] Figure 17 This is a perspective view showing a schematic representation of the stator involved in Embodiment 4.

[0027] Figure 18 This is a schematic cross-sectional view showing the rotary electric motor involved in Embodiment 5.

[0028] Figure 19 This is a schematic cross-sectional view showing the rotary electric motor involved in Embodiment 6. Detailed Implementation

[0029] [The problem to be solved by this invention]

[0030] The goal is to improve the magnetic characteristics of rotary motors with axial clearance.

[0031] One object of the present invention is to provide a ferrite core, stator core, and stator capable of constructing an axially spaced rotary electric motor with excellent magnetic properties. Another object of the present invention is to provide a rotary electric motor with excellent magnetic properties. A further object of the present invention is to provide a method for manufacturing the aforementioned ferrite core.

[0032] [Effects of the Invention]

[0033] The iron chip, stator core, and stator involved in this invention can be used to construct an axially gapped rotary motor with excellent magnetic properties. The rotary motor involved in this invention exhibits excellent magnetic properties. The method for manufacturing the iron chip involved in this invention can produce an iron chip capable of constructing an axially gapped rotary motor with excellent magnetic properties.

[0034] Description of Embodiments of the Invention

[0035] First, embodiments of the present invention will be described.

[0036] (1) One aspect of the present invention relates to a stator core of a rotary motor in which the iron chip is configured in an annular shape to form an axially spaced type. The iron chip has: a columnar first component extending axially in the stator core; and a plate-shaped second component disposed at a first end of the first component in the axial direction of the stator core. The first component and the second component are integrally formed from a powder-pressed body having a plurality of soft magnetic particles. The soft magnetic particles are flat in shape. In a first cross-section of the first component along the axial and radial directions of the stator core, the first average aspect ratio of the soft magnetic particles is 1.2 or more. In a second cross-section of the second component orthogonal to the axial direction of the stator core, the soft magnetic particles have a flattened shape. The second average aspect ratio of the magnetic particles is 1.2 or greater. The first average aspect ratio is the ratio of the average length L11 to the average length L12 of the first cross-section, L12 / L11. The second average aspect ratio is the ratio of the average length L21 to the average length L22 of the second cross-section, L22 / L21. The average length L11 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L12 is the average length of the soft magnetic particles along the axial direction of the stator core. The average length L21 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L22 is the average length of the soft magnetic particles along the circumferential direction of the stator core.

[0037] The aforementioned iron chip can be used to construct an axially gapped rotary motor with excellent magnetic properties. This is because, in either the first or second component, the soft magnetic particles are oriented in the direction of the magnetic flux, and the number of grain boundaries forming the magnetic gap is small. The details of the reasoning are as follows.

[0038] When constructing an axially spaced rotary motor using the aforementioned iron chip, magnetic flux passes through the iron chip. The magnetic flux passes sequentially through the second component and then the first component. Alternatively, the magnetic flux passes sequentially through the first component and then the second component. In any of these sequences, the magnetic flux passing through the first component is along the direction extending from the first component, i.e., the axial direction of the stator core. The magnetic flux passing through the second component is along the surface direction of the second component, i.e., the circumferential direction of the stator core. As described above, in the iron chip, the magnetic flux passing through the first component and the magnetic flux passing through the second component travel in different directions.

[0039] The first component of the aforementioned iron chip has a first average aspect ratio of 1.2 or more in its first cross-section. That is, in the first cross-section of the first component, the length of the soft magnetic particle along the axial direction of the stator core is longer than its length along the radial direction of the stator core. In other words, the length of the soft magnetic particle along the direction of magnetic flux is longer than its length along the direction orthogonal to the direction of magnetic flux.

[0040] The second component of the aforementioned iron chip has a second average aspect ratio of 1.2 or more in its second cross-section. That is, in the second cross-section of the second component, the length of the soft magnetic particle along the circumferential direction of the stator core is longer than its length along the radial direction of the stator core. In other words, the length of the soft magnetic particle along the direction of magnetic flux is longer than its length along the direction orthogonal to the direction of magnetic flux.

[0041] In a first cross-section of the first component, a square first field of view is taken. The first field of view is defined by having a pair of first sides along the axial direction of the stator core and a pair of second sides along the radial direction of the stator core. In a second cross-section of the second component, a square second field of view is taken. The second field of view is defined by having a pair of first sides along the radial direction of the stator core and a pair of second sides in a direction orthogonal to the radial direction of the stator core.

[0042] The first average aspect ratio of the soft magnetic particles satisfies 1.2 or greater, thus, in the first field of view, the number of soft magnetic particles arranged axially in the stator core is less than the number of soft magnetic particles arranged radially side-by-side in the stator core. In other words, in the first field of view, the number of soft magnetic particles arranged side-by-side in the direction of magnetic flux is less than the number of soft magnetic particles arranged side-by-side in a direction orthogonal to the direction of magnetic flux. That is, in the first field of view, the number of grain boundaries dividing the stator core axially is less. In other words, in the first field of view, the number of grain boundaries dividing along the direction of magnetic flux is less. Grain boundaries refer to the boundaries between adjacent soft magnetic particles.

[0043] The second average aspect ratio of the soft magnetic particles satisfies 1.2 or greater, thus, in the second field of view, the number of soft magnetic particles arranged circumferentially in the stator core is less than the number of soft magnetic particles arranged radially side-by-side in the stator core. In other words, in the second field of view, the number of soft magnetic particles arranged side-by-side in the direction of magnetic flux is less than the number of soft magnetic particles arranged side-by-side in a direction orthogonal to the direction of magnetic flux. That is, in the second field of view, the number of grain boundaries dividing the stator core circumferentially is less. In other words, in the second field of view, the number of grain boundaries dividing along the direction of magnetic flux is less.

[0044] The first and second components of the iron chip are integrally formed from a powder-pressed body. Details of the iron chip described above are as follows: it can be manufactured by setting the direction of pressurizing the raw material powder within the mold and the direction of pulling the manufactured iron chip out of the mold along the radial direction of the stator core of the iron chip.

[0045] Conventionally, iron chips, in which the first and second components are integrally formed from pressed powder, are manufactured by setting the pressing direction and the pulling direction along the axial direction of the stator core of the iron chip. As described above, the pressing direction and pulling direction of the above-described iron chip differ from those of existing iron chips during manufacturing.

[0046] The existing iron chip powder molding body is manufactured by pressing raw material powder filled into the mold cavity of a die through an upper punch and a lower punch. The pressing direction is along the axial direction of the stator core of the iron chip, that is, the side-by-side direction of the first and second components. The first and second axial end faces of the stator core in the powder molding body are formed by the upper and lower end faces of the lower punch. The first and second circumferential direction faces of the stator core in the powder molding body are formed by the inner circumferential surface of the lower punch. The outer and inner circumferential direction faces of the stator core in the powder molding body are formed by the inner circumferential surface of the die cavity. That is, the first axial end face of the first component and the first axial end face of the second component are formed by the upper end face of the lower punch. The second axial end face of the second component is formed by the lower end face of the upper punch. The first and second circumferential surfaces of the first component are formed by the inner circumferential surface of the lower punch. The outer and inner circumferential surfaces of the first and second components are formed by the inner circumferential surface of the die cavity. The direction in which the pressed powder is pulled out of the die is the same as the direction of pressure, which is the axial direction along the stator core of the iron chip, that is, the side-by-side direction of the first and second components.

[0047] The magnetic flux of the existing iron chip passing through the first component is, in the same manner as the second component of the aforementioned iron chip, along the axial direction of the stator core. The magnetic flux of the existing iron chip passing through the second component is, in the same manner as the second component of the aforementioned iron chip, along the circumferential direction of the stator core.

[0048] In the existing first component of the iron chip, a first cross-section identical to the first cross-section of the aforementioned first component of the iron chip is taken. Furthermore, in the existing first cross-section of the iron chip, a square first observation field of view identical to the aforementioned first observation field of view is taken. In the existing second component of the iron chip, a second cross-section identical to the second cross-section of the aforementioned second component of the iron chip is taken. Furthermore, in the existing second cross-section of the iron chip, a square second observation field of view identical to the aforementioned second observation field of view is taken.

[0049] In a first cross-section of the first component of the existing iron chip, unlike the first cross-section of the first component of the aforementioned iron chip, the length of the soft magnetic particles along the axial direction of the stator core is shorter than their length along the radial direction of the stator core. Therefore, in the first field of view of the existing iron chip, unlike the first field of view of the aforementioned iron chip, the number of soft magnetic particles arranged side-by-side in the axial direction of the stator core is greater than the number of soft magnetic particles arranged side-by-side in the radial direction of the stator core. In other words, in the first field of view of the existing iron chip, unlike the first field of view of the aforementioned iron chip, the number of soft magnetic particles arranged side-by-side in the direction of magnetic flux is greater than the number of soft magnetic particles arranged side-by-side in a direction orthogonal to the direction of magnetic flux. That is, in the first field of view of the existing iron chip, unlike the first field of view of the aforementioned iron chip, the number of grain boundaries dividing the stator core axially is greater. In other words, in the first field of view of the existing iron chip, unlike the first field of view of the aforementioned iron chip, the number of grain boundaries dividing along the direction of magnetic flux is greater.

[0050] In the second cross-section of the second component of the existing iron chip, unlike the second cross-section of the second component of the aforementioned iron chip, the lengths of the soft magnetic particles along the circumferential direction and the radial direction of the stator core are the same. Therefore, in the second field of view of the existing iron chip, unlike the second field of view of the aforementioned iron chip, the number of soft magnetic particles arranged circumferentially alongside the stator core and the number of soft magnetic particles arranged radially alongside the stator core are the same. In other words, in the second field of view of the existing iron chip, unlike the second field of view of the aforementioned iron chip, the number of grain boundaries dividing the stator core circumferentially and the number of grain boundaries dividing the stator core radially are the same. That is, in the second field of view of the existing iron chip, unlike the second field of view of the aforementioned iron chip, the number of soft magnetic particles arranged circumferentially along the direction of magnetic flux and the number of soft magnetic particles arranged circumferentially along the direction orthogonal to the direction of magnetic flux are the same. In the second field of view of the existing iron chip, unlike the second field of view of the iron chip mentioned above, the number of grain boundaries segmented along the direction of magnetic flux and the number of grain boundaries segmented in the direction orthogonal to the direction of magnetic flux are of the same degree.

[0051] As described above, compared to existing iron chip first components, the first component of the aforementioned iron chip has fewer grain boundaries that divide the magnetic flux direction. These grain boundaries become magnetic gaps. The more magnetic gaps there are, the greater the magnetic reluctance becomes. Therefore, compared to existing iron chip first components, the aforementioned iron chip's first component facilitates the passage of magnetic flux. The ease of magnetic flux passage in the aforementioned iron chip's second component is the same as that in existing iron chip second components. Thus, compared to existing iron chips, the aforementioned iron chip facilitates the passage of magnetic flux.

[0052] (2) As one method of the above-mentioned iron chip, the relative density of the pressed powder molded body is 85% or more.

[0053] The aforementioned iron chips are high-density, thus enabling the construction of axially spaced rotary motors with excellent magnetic properties, such as saturation magnetic flux density. Furthermore, the iron chips possess excellent mechanical properties, including strength.

[0054] (3) As one method of the above-mentioned iron chip, the soft magnetic particles are made of pure iron or iron-based alloys, and the iron-based alloys include Fe-Si alloys, Fe-Al alloys or Fe-Si-Al alloys.

[0055] The aforementioned iron chips are high-density and have excellent dimensional accuracy. However, the material itself is relatively soft, making the soft magnetic particles prone to deformation during the molding and pressing process.

[0056] (4) As one method of the above-mentioned iron chip, the average particle size of the soft magnetic particles is 30 μm or more.

[0057] The soft magnetic particles have an average particle size of 30 μm or more, which easily increases the relative permeability. The aforementioned iron chip containing these soft magnetic particles exhibits low loss. Therefore, this iron chip can be easily used to construct a low-loss axially gapped rotary motor.

[0058] (5) As one method of the above-mentioned iron chip, the proportion of the second height to the first height of the iron chip is more than 80%, the first height is the length of the iron chip along the axial direction of the stator core, and the second height is the length of the region of the iron chip other than the second component along the axial direction of the stator core.

[0059] The aforementioned iron chip has a length that, excluding the second component, accounts for a larger proportion of the total length of the iron chip. Therefore, compared to the aforementioned iron chip and the existing iron chip, with the iron chip length remaining constant, the aforementioned iron chip makes it easier to construct an axially gap-type rotary motor with excellent magnetic properties.

[0060] (6) As one embodiment of the above-mentioned iron chip, the second component has: an outer peripheral surface disposed on the outer peripheral side of the stator core; an inner peripheral surface disposed on the inner peripheral side of the stator core; and a first end face disposed on the first end side of the stator core in the axial direction, wherein the corner between the outer peripheral surface and the first end face and the corner between the inner peripheral surface and the first end face are chamfered, and the chamfer length of the corner is 0.1 mm or more and 0.5 mm or less.

[0061] The chamfer length is within the above range, thus the corner is not easily damaged.

[0062] (7) As one embodiment of the above-mentioned iron chip, a plate-shaped third component is provided on the second end side of the first component along the axial direction. The first component has a circumferential surface connected to the second component and the third component. The second component has a protrusion extending outward from the circumferential surface of the first component. The third component has a protrusion extending outward from the circumferential surface of the first component. The first component, the second component and the third component are composed of an integrally formed powder-pressed body.

[0063] The aforementioned iron chips exhibit excellent productivity. The reasons are as follows.

[0064] Conventionally, iron chips comprising a first component, a second component, and a third component are, for example, constructed by combining a powder-pressed body in which the first and second components are integrally formed, with a third component constructed separately from the powder-pressed body. Alternatively, existing iron chips are, for example, constructed by combining a powder-pressed body in which the first and third components are integrally formed, with a second component constructed separately from the powder-pressed body. That is, existing iron chips require the fabrication and assembly of at least two components. Therefore, the manufacturing of existing iron chips requires numerous steps and a long manufacturing time. In addition, the manufacturing of existing iron chips requires at least two molds.

[0065] On the other hand, the aforementioned iron chip comprises the first, second, and third components as a single-piece pressed powder molded body, thus eliminating the need to assemble multiple components. Therefore, compared to existing iron chips, the aforementioned iron chip can be manufactured with fewer steps and in a shorter time. Furthermore, since the first, second, and third components are constructed as a single pressed powder molded body, it can be manufactured using a single mold. This reduces the costs associated with mold making and maintenance, enabling the aforementioned iron chip to be manufactured at a low cost.

[0066] The aforementioned iron chip cannot be manufactured using existing methods where the pressing and pulling directions of iron chips are in the same direction. This is because the second and third components each have protrusions, which hook onto the inner circumferential surface of the die cavity, preventing the iron chip from being pulled out of the die.

[0067] The aforementioned iron chip can be manufactured by setting the pressure direction and the extraction direction to be along the radial direction of the stator core, as detailed below. The outer and inner circumferential surfaces of the stator core in the iron chip are formed by the lower end face of the upper punch and the upper end face of the lower punch. The circumferential surfaces of the stator core in the iron chip, in the first and second directions, and the axial surfaces of the stator core, in the first and second ends, are formed by the inner circumferential surface of the die cavity. In this case, even if the second and third components each have protrusions, the protrusions will not hook onto the inner circumferential surface of the die cavity, thus allowing the iron chip to be extracted from the die.

[0068] (8) As one embodiment of the iron chip in (7) above, the first component, the second component, and the third component each have: an outer peripheral surface disposed on the outer peripheral side of the stator core; an inner peripheral surface disposed on the inner peripheral side of the stator core; a first side surface disposed on the first circumferential direction side of the stator core and connected to the outer peripheral surface and the inner peripheral surface; and a second side surface disposed on the second circumferential direction side of the stator core and connected to the outer peripheral surface and the inner peripheral surface. In each of the first component, the second component, and the third component, the length between the first side surface and the second side surface of the outer peripheral surface is greater than the length between the first side surface and the second side surface of the inner peripheral surface. The length between the second side surfaces is long. Each of the first component, the second component, and the third component has a first parallel surface connected to the outer peripheral surface, a second parallel surface connected to the inner peripheral surface, and a first inclined surface connected to the first parallel surface and the second parallel surface. In each of the first component, the second component, and the third component, the first parallel surface of the first side surface and the first parallel surface of the second side surface are parallel, the second parallel surface of the first side surface and the second parallel surface of the second side surface are parallel, and the first parallel surface of the first side surface and the second parallel surface of the first side surface are parallel.

[0069] The aforementioned iron chips have a relatively high density. The reasons are as follows. Details of the first and second parallel surfaces will be described later. In the die cavity of the mold, a straight section along the pressing direction of the upper and lower punches can be formed. Therefore, sufficient pressure can be applied to the raw material powder constituting the iron chips.

[0070] The aforementioned iron chip production rate is excellent. The reasons are as follows. Details of the first inclined surface will be described later. In the die cavity of the mold, a tapered portion intersecting the pressing directions of the upper and lower punches can be formed. The die cavity has a straight section, thereby suppressing contact between the upper and lower punches and the inner circumferential surface of the tapered portion. Therefore, the die life is increased, and thus the number of iron chips that can be produced from a single die is increased.

[0071] (9) As one embodiment of the iron chip in (8) above, in each of the first component, the second component and the third component, the angle formed by the extension of the first parallel surface of the first side and the first inclined surface is 5° or more and 20° or less, and the angle formed by the extension of the first parallel surface of the second side and the first inclined surface is 5° or more and 20° or less.

[0072] The angle formed by the aforementioned iron chip in the first component satisfies the aforementioned range, thereby facilitating the winding of the first component and the construction of the stator. The angle formed by the aforementioned iron chip in the second component satisfies the aforementioned range, thereby facilitating its configuration into a ring shape and the construction of the stator core. The angle formed by the aforementioned iron chip in the third component satisfies the aforementioned range, thereby suppressing density fluctuations within the iron chip.

[0073] (10) As one embodiment of the iron chip described in (8) or (9) above, the protrusion of the second component and the protrusion of the third component each have a first protrusion extending toward the first direction of the circumferential direction and a second protrusion extending toward the second direction of the circumferential direction. The protrusion amount of the first protrusion of the second component is greater than that of the first protrusion of the third component, and the protrusion amount of the second protrusion of the second component is greater than that of the second protrusion of the third component. The first inclined surface of the first protrusion of the second component has a portion extending outward from a first imaginary surface, and the first inclined surface of the second protrusion of the second component has a portion extending outward from a second imaginary surface. The first imaginary surface is a plane that connects the connection portion of the first parallel surface and the first inclined surface to the connection portion of the second parallel surface and the inner circumferential surface on the first side surface of the first protrusion of the second component. The second imaginary surface is a plane that connects the connection portion of the first parallel surface and the first inclined surface to the connection portion of the second parallel surface and the inner circumferential surface on the second side surface of the second protrusion of the second component.

[0074] The aforementioned iron chips are easy to use to construct stator cores with large magnetic circuit areas. The reasons are as follows.

[0075] A stator core is constructed by arranging multiple iron laminations in a ring. Sometimes, this stator core is constructed by combining first and second iron laminations that are circumferentially adjacent to each other in contact.

[0076] For example, in the case where the first side surface of the first protrusion and the second side surface of the second protrusion each have a first parallel surface, a second parallel surface, and a first inclined surface, and the first inclined surface does not have the aforementioned protruding portion, the situation becomes as follows. When the iron chip is arranged in a ring shape, if an attempt is made to bring the first side surface of the first protrusion of the second component of the first iron chip and the second side surface of the second protrusion of the second component of the second iron chip into contact, then the first corner of the first iron chip and the second corner of the second iron chip will come into contact. The first corner is the corner between the first side surface of the first protrusion of the second component and the inner peripheral surface. The second corner is the corner between the second side surface of the second protrusion of the second component and the inner peripheral surface. Therefore, it is impossible to make the first side surface of the first protrusion of the second component of the first iron chip and the second side surface of the second protrusion of the second component of the second iron chip into sufficient contact.

[0077] In contrast, the aforementioned iron chip has a first side surface of the first protrusion and a second side surface of the second protrusion, each having a first parallel surface, a second parallel surface, and a first inclined surface. The first inclined surface has a portion that extends further than each of the first and second imaginary surfaces. When the aforementioned iron chip is arranged in a ring shape, even if the first side surface of the first protrusion of the second component of the first iron chip and the second side surface of the second protrusion of the second component of the second iron chip come into contact, it is possible to prevent the first corner of the first iron chip and the second corner of the second iron chip from coming into contact. Therefore, it is possible to ensure sufficient contact between the first side surface of the first protrusion of the second component of the first iron chip and the second side surface of the second protrusion of the second component of the second iron chip.

[0078] (11) As one embodiment of the iron chip of (10) above, the first side of the first protrusion of the second component has one selected from the group consisting of at least one of a concave portion and a convex portion, a step and a second inclined surface, and the second side of the second protrusion of the second component has one selected from the group consisting of at least one of a convex portion corresponding to the concave portion of the first side and a concave portion corresponding to the convex portion of the first side, a step corresponding to the step of the first side and a second inclined surface corresponding to the second inclined surface of the first side.

[0079] The aforementioned iron chips can easily form a stator core with a large magnetic circuit area. The reason is as follows: The first and second iron chips, which are circumferentially adjacent in the stator core, can be fitted together through the aforementioned steps or the aforementioned uneven surfaces, or the aforementioned second inclined surfaces can be brought into contact. This allows for sufficient contact between the first and second iron chips, thus increasing the contact area between them.

[0080] (12) As one form of the iron chip described in (10) or (11) above, the third component is provided to have a first end face disposed on the opposite side to the side opposite to the second component, the first end face being convex toward the opposite side.

[0081] The aforementioned iron chips can be used to construct an axially backlash type rotary motor with low noise and vibration. The reasons are as follows: The stator and rotor of the axially backlash type rotary motor are arranged opposite each other. The stator is constructed by arranging coils in each first component of the stator core. The stator core is constructed by arranging multiple iron chips in a ring. The first end face of the iron chip is convex, which easily suppresses abrupt changes in the magnetic flux of the rotor magnet acting on the iron chip. The ease of suppressing abrupt changes in magnetic flux easily reduces cogging torque. Lower cogging torque reduces noise and vibration.

[0082] (13) As one of the iron chips described in (8) to (12) above, the outer peripheral surfaces of the first component, the second component and the third component each have a curved surface that protrudes toward the outer peripheral side, and the inner peripheral surfaces of the first component, the second component and the third component each have a curved surface that protrudes toward the inner peripheral side.

[0083] The aforementioned iron chip can suppress density fluctuations within the iron chip.

[0084] (14) As one of the iron chips described in (8) to (13) above, the first seam between the protrusion of the second component and the peripheral surface of the first component, and the second seam between the protrusion of the third component and the peripheral surface of the first component are rounded.

[0085] The aforementioned iron chip has rounded corners at the first and second seams, thus making it less likely to cause damage starting from each seam.

[0086] (15) As one method of the iron chip in (14) above, the bending radius of the first seam and the bending radius of the second seam are 0.2 mm or more and 4.0 mm or less.

[0087] The bending radius of the first and second seams of the aforementioned iron chip is 0.2 mm or more, which reduces the load on the mold during the manufacture of the iron chip. The bending radius of the first and second seams of the aforementioned iron chip is 4.0 mm or less, which makes it easier to wind the coil during stator construction, thus facilitating an increase in the number of coil turns.

[0088] (16) As one of the iron chips described in (8) to (15) above, the second component and the third component each have a first end face arranged on opposite sides of each other, and the corners between the outer peripheral surface and the first end face and between the inner peripheral surface and the first end face of the second component and the third component are chamfered.

[0089] The aforementioned iron chip has chamfered corners, making the corners less prone to damage.

[0090] (17) As one of the iron chips described in (8) to (16) above, the total area of ​​the outer peripheral surfaces of the first component, the second component and the third component is more than 1 and less than 4 times the total area of ​​the inner peripheral surfaces of the first component, the second component and the third component.

[0091] The total area of ​​the outer circumferential surfaces of the aforementioned iron chip is more than twice the total area of ​​the inner circumferential surfaces, making it easy to configure it into a ring shape and construct a stator core. The total area of ​​the outer circumferential surfaces of the aforementioned iron chip is less than four times the total area of ​​the inner circumferential surfaces, making it easy to manufacture. The relatively large proportion of the total area of ​​the inner circumferential surfaces results in a large area being pushed by the lower punch when the iron chip is pulled out of the mold. Therefore, it is easier to suppress damage to the iron chip when it is pulled out of the mold.

[0092] (18) As one of the iron chips described in (8) to (17) above, the difference in relative density between the first part on the first circumferential direction side and the second part on the second circumferential direction side, and the third part between the first part and the second part, which are divided into three parts by the imaginary surface of the first side side along the second parallel surface and the imaginary surface of the second side side along the second parallel surface, is 5.0% or less.

[0093] The difference in relative density of the aforementioned iron chips is small, therefore the physical properties such as magnetic properties within the iron chips are essentially uniform.

[0094] (19) As one method of the iron chip described in (7) to (18) above, the difference in relative density between the component with the largest relative density and the component with the smallest relative density among the first component, the second component and the third component is 5% or less.

[0095] The difference in relative density of the aforementioned iron chips is small, therefore the physical properties such as magnetic properties within the iron chips are essentially uniform.

[0096] (20) In one aspect of the present invention, the stator core is an axially gap type stator core of a rotary motor, having a plurality of iron chips arranged in an annular shape, each of the plurality of iron chips being any one of the iron chips described in (1) to (19) above.

[0097] The stator core described above has the aforementioned iron core, thereby enabling the construction of an axially spaced rotary motor with excellent magnetic properties.

[0098] (21) As one method of the stator core described above, the length fluctuation between the first end face and the second end face of each of the plurality of iron chips in the axial direction is less than 0.1 mm.

[0099] The aforementioned length variation of the stator core is very small. Therefore, the aforementioned stator core can be used to construct an axially backlash type rotary motor with low noise and vibration. The reason is as follows. As described above, the stator and rotor of the axially backlash type rotary motor are arranged opposite each other. The stator is constructed by arranging coils in the first component of each lamellar piece of the stator core. The aforementioned length variation of the stator core is small, thereby the variation in the distance between the stator and rotor is small. The small variation in the distance results in small torque pulsation. Small torque pulsation makes it less likely for noise and vibration to increase.

[0100] (22) In one aspect of the present invention, the stator is an axially gap type rotary motor stator having the stator core described above (20) or (21) and coils arranged in each of the first components of the stator core.

[0101] The stator described above has the stator core described above, thereby enabling the construction of an axially spaced rotary motor with excellent magnetic properties.

[0102] (23) One aspect of the present invention relates to a rotary motor of the axial clearance type having a rotor and a stator, wherein the stator is the stator of (22) above.

[0103] The aforementioned rotary electric motor has the aforementioned stator, thereby exhibiting excellent magnetic properties.

[0104] (24) As one method of the above-mentioned rotary motor, the first magnetic reluctance of the iron chip accounts for more than 2% of the magnetic reluctance of the rotary motor, and the first magnetic reluctance is the magnetic reluctance of the area of ​​the iron chip other than the second component.

[0105] As described above, the magnetic reluctance of the first component of the aforementioned iron chip is lower than that of the first component of a conventional iron chip. Therefore, the higher the proportion of the aforementioned first magnetic reluctance, the superior magnetic characteristics of the aforementioned rotary motor having the aforementioned iron chip compared to a rotary motor having a conventional iron chip. The magnetic reluctance of the axial clearance type rotary motor will be described later.

[0106] (25) One aspect of the present invention relates to a method for manufacturing an iron chip for a stator core of a rotary motor configured in an annular shape and forming an axial gap type. The method for manufacturing an iron chip includes the steps of: filling a mold with a raw material powder comprising a plurality of soft magnetic particles in the shape of spheres; and compressing the raw material powder in the mold to form a molded body. The iron chip has: a columnar first component extending axially in the stator core; and a plate-shaped second component disposed at a first end of the first component in the axial direction of the stator core. The direction of compression of the raw material powder is along the radial direction of the stator core.

[0107] The aforementioned method for manufacturing iron chips uses spherical soft magnetic particles and sets the direction of compression of the raw material powder to the radial direction of the stator core, thereby enabling the manufacture of the iron chip according to one aspect of the present invention. Therefore, the aforementioned method for manufacturing iron chips can produce iron chips that can be used to construct axially spaced rotary motors with excellent magnetic properties.

[0108] Detailed Description of Embodiments of the Invention

[0109] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote the same names of objects.

[0110] Implementation Method 1

[0111] Reference Figures 1 to 11 The iron chip 1 according to Embodiment 1 will be described below. The iron chip 1 of this embodiment is as follows: Figure 16 As described later, the stator core 7 is constructed in a ring shape. This stator core 7 is used for reference. Figure 18 , Figure 19 The axial clearance type rotary motor 9, described later, will be detailed later. The iron chip 1 in this method is as follows... Figure 1 As shown, it has a columnar first component 10 and a plate-shaped second component 20. The first component 10 extends axially in the stator core 7. The second component 20 is disposed at the first end side of the first component 10 in the aforementioned axial direction. One feature of the stator core 1 of this embodiment is that it satisfies all of the following structures (a) to (c).

[0112] (a) The first component 10 and the second component 20 are integrally formed by compression molding in a specific direction.

[0113] (b) in Figure 7 The first cross-section of the first component 10 shown is shown. Figure 8 The first average aspect ratio of the soft magnetic particles 40 shown meets a specific range.

[0114] (c) in Figure 5 The second cross-section of the second component 20 shown is shown. Figure 9 The second average aspect ratio of the soft magnetic particles 40 shown meets a specific range.

[0115] The first component 10 and the second component 20 are integrally molded, meaning that the first component 10 and the second component 20 are integrated into one unit without mechanical connection using screws or adhesives.

[0116] In this embodiment, the iron chip 1, based on the first component 10 and the second component 20, also has a plate-shaped third component 30. The third component 30 is disposed at the second end side of the first component 10 along the aforementioned axial direction. This iron chip 1 is composed of a pressed powder molded body in which the first component 10, the second component 20, and the third component 30 are integrally formed. As described above, the integral forming of the first component 10, the second component 20, and the third component 30 means that, without mechanical connection using screws or the like, or bonding using adhesives, the first component 10, the second component 20, and the third component 30 are integrated through molding. Furthermore, as referred to... Figure 15 As will be described later, the iron chip 1 may not have a third component 30 as long as it has the first component 10 and the second component 20.

[0117] The direction along the radial direction of the stator core 7 of the iron chip 1 is set as the X-axis direction.

[0118] The direction along the axial direction of the stator core 7 of the iron chip 1 is set as the Z-axis direction.

[0119] The direction orthogonal to both the X-axis and Z-axis of iron chip 1 is set as the Y-axis direction.

[0120] The inner circumference of the stator core 7 of the iron chip 1 in the X-axis direction is defined as the X1 direction, and the outer circumference of the stator core 7 is defined as the X2 direction.

[0121] The side of the iron chip 1 relative to the second component 20 of the first component 10 in the Z-axis direction is designated as the Z1 direction, and the side of the third component 30 relative to the first component 10 is designated as the Z2 direction.

[0122] The Z1 direction is the first end side of the first component 10.

[0123] The Z2 direction is the second end side of the first component 10.

[0124] The first direction side of the stator core 7 of the iron chip 1 in the Y-axis direction is set as the Y1 direction, and the second direction side of the stator core 7 is set as the Y2 direction.

[0125] [First Component]

[0126] The first component 10 is a columnar component extending in the Z-axis direction. The first component 10 forms teeth in either the case where the stator core 7 of an axially spaced rotary motor 9 is constructed from iron chips 1 in a dual-stator, single-rotor configuration, or in the case where the stator core 7 of an axially spaced rotary motor 9 is constructed from a single-stator, dual-rotor configuration. The axially spaced rotary motor 9 in a dual-stator, single-rotor configuration... Figure 18 As shown, the rotor 90 is assembled with two stators 8 sandwiched between it. The axial clearance type rotary motor 9 with a single stator and dual rotor configuration is as follows... Figure 19 As shown, the stator 8 is assembled with two rotors 90 sandwiched between it. For ease of explanation, the term "double stator, single rotor" will sometimes be referred to as DS / SR, and "single stator, double rotor" as SS / DR.

[0127] like Figure 3 As shown, the proportion of the second height H10 of the iron chip 1 to the first height H1 is, for example, 80% or more. Both the first height H1 and the second height H10 are lengths in the Z-axis direction. The first height H1 is the overall length of the iron chip 1, which in this embodiment is the length between the first end face 26 of the second component 20 and the first end face 36 of the third component 30 (described later). The second height H10 is the length of the area excluding the second component, which in this embodiment is the combined height of the first component 10 and the third component 30. Specifically, the second height H10 is the length between the second end face 27 of the second component 20 and the first end face 36 of the third component 30 (described later). The larger the proportion, the easier it is to obtain the effect of the iron chip 1 satisfying the above structure (b). This effect will be described later. The proportion is also 82% or more, and more specifically 85% or more. The upper limit of the proportion is, for example, 95%. That is, the above percentages are 80% or more and 95% or less, and 82% or more and 93% or less, and specifically 85% or more and 90% or less.

[0128] Examples of the shape of the first component 10 include a square prism and a cylinder. Examples of square prisms include a quadrilateral prism whose cross-sectional shape is quadrilateral when cut by a plane orthogonal to the Z-axis. Examples of quadrilateral prisms include a trapezoidal prism whose cross-sectional shape is trapezoidal. Examples of cross-sections are the same in the Z-axis direction. "Trapezoidal shape" not only refers to a geometric trapezoid, but also includes shapes with rounded corners, as in this example, encompassing a range that can be substantially considered a trapezoid. "Trapezoidal shape" includes trapezoids with two legs of equal length, such as an isosceles trapezoid, as well as trapezoids with two legs of different lengths, such as a right trapezoid. This is also true for the second component 20 and the third component 30, which will be described later.

[0129] The shape of the first component 10 in this method is as follows: Figure 1 , Figure 4 As shown, the cross-sectional shape of the first component 10 is a trapezoidal column. In this cross-sectional shape, the side on the X2 direction is longer, and the side on the X1 direction is shorter. The cross-sectional shape of the first component 10 is the same in the Z-axis direction. If the shape of the first component 10 is a trapezoidal column, it is easier to ensure a large cross-sectional area. Furthermore, it is easier to reduce the dead space of the iron chip 1 and to construct a stator 8 with a high duty cycle.

[0130] First component 10 Figure 1 , Figure 3 As shown, it has a peripheral surface 11 connected to the second component 20 and the third component 30. Figure 1 , Figure 3 The peripheral surface 11 of the first component 10 shown is as follows Figure 4 The device shown has an outer peripheral surface 12, an inner peripheral surface 13, a first side surface 14a, and a second side surface 14b. The outer peripheral surface 12 is located on the X2 direction side. The inner peripheral surface 13 is located on the X1 direction side. The first side surface 14a and the second side surface 14b are located on opposite sides of the circumferential direction of the stator core 7 of the chip 1. That is, the first side surface 14a is located on the first circumferential direction side of the stator core 7 of the chip 1. The second side surface 14b is located on the second circumferential direction side of the stator core 7 of the chip 1. The positional relationship of the outer peripheral surface 12, the inner peripheral surface 13, the first side surface 14a, and the second side surface 14b is also the same in the second component 20 and the third component 30 described later.

[0131] The outer peripheral surface 12 is connected to the outer peripheral edge of the first side surface 14a and the outer peripheral edge of the second side surface 14b. The inner peripheral surface 13 is connected to the inner peripheral edge of the first side surface 14a and the inner peripheral edge of the second side surface 14b. That is, the first side surface 14a and the second side surface 14b are connected to the outer peripheral surface 12 and the inner peripheral surface 13.

[0132] The length between the first side surface 14a and the second side surface 14b of the outer peripheral surface 12 is longer than the length between the first side surface 14a and the second side surface 14b of the inner peripheral surface 13. The outer peripheral surface 12 in this embodiment has a curved surface convex towards the X2 direction. Alternatively, the outer peripheral surface 12 can also be composed of a plane. The inner peripheral surface 13 in this embodiment has a curved surface convex towards the X1 direction. Alternatively, the inner peripheral surface 13 can also have a curved surface convex towards the X2 direction, and can also be composed of a plane. The curvature radii of the outer peripheral surface 12 and the inner peripheral surface 13 can be the same or different from each other.

[0133] The first side surface 14a and the second side surface 14b each have a first parallel surface 141, a second parallel surface 142, and a first inclined surface 143. The first parallel surfaces 141 of the first side surface 14a and the second side surface 14b are parallel to each other. The second parallel surfaces 142 of the first side surface 14a and the second parallel surface 142 of the first side surface 14a are parallel to each other. The first parallel surfaces 141 and 142 are parallel to the X-axis direction of the iron chip 1. The X-axis direction refers to the direction of a straight line passing through the center of the stator core 7 and bisecting the iron chip 1 in the circumference of the stator core 7. The first parallel surface 141 is connected to the outer circumferential surface 12. The second parallel surface 142 is connected to the inner circumferential surface 13. The first inclined surface 143 is connected to the first parallel surface 141 and the second parallel surface 142.

[0134] The lengths of the first parallel plane 141 and the second parallel plane 142 along the X-axis are preferably 0.3 mm or more and 25 mm or less, depending on the size of the iron chip 1. If the lengths are above or below the lower limit, the reference length can be suppressed. Figure 11 Damage to the die 5 that accompanies contact with the lower punch 55 and the die 50 will be described later. The manufacturing method of the iron chip 1 will be described later. If the value is above the aforementioned lower limit, sufficient pressure can be applied to the raw material powder constituting the iron chip 1. If the value is below the aforementioned upper limit, the cross-sectional area of ​​the first component 10 can be increased, thereby enabling an increase in the torque of the axially gap type rotary motor 9 and suppression of iron loss. The length of the first parallel surface 141 and the second parallel surface 142 along the X-axis is further preferably 0.4 mm or more and 20 mm or less, and particularly preferably 0.5 mm or more and 15 mm or less. The appropriate range described above for the lengths of the first parallel plane 141 and the second parallel plane 142 of the first side surface 14a and the second side surface 14b of the first component 10 along the X-axis direction is also the same for the first parallel plane 241 and the second parallel plane 242 of the first side surface 24a and the second side surface 24b of the second component 20, and for the first parallel plane 341 and the second parallel plane 342 of the first side surface 34a and the second side surface 34b of the third component 30, as described later.

[0135] like Figure 4 As shown, the first tilt angle θ11 and the second tilt angle θ12 of the first tilt surface 143 are preferably 5° or more and 20° or less. If the first tilt angle θ11 and the second tilt angle θ12 are 5° or more and 20° or less, the winding described later can be easily wound around the circumferential surface 11 of the first component 10, thus facilitating the construction of... Figure 16The stator core 7 shown. The first tilt angle θ11 and the second tilt angle θ12 are preferably 5.5° or more and 18° or less, particularly preferably 6° or more and 16° or less. The first tilt angle θ11 and the second tilt angle θ12 are preferably the same angle, but they may be different. The first tilt angle θ1 refers to the angle formed between the extension surface E11 of the first parallel surface 141 of the first side surface 14a and the first tilt surface 143. The second tilt angle θ12 refers to the angle formed between the extension surface E12 of the first parallel surface 141 of the second side surface 14b and the first tilt surface 143.

[0136] [Second Component]

[0137] Second component 20 Figure 1 , Figure 3 As shown, the first component 10 is a plate-shaped component disposed at its first end in the Z-axis direction. The second component 20 constitutes a yoke in the case of a stator core 7 of a rotary motor 9 with an axial clearance type, constructed from iron chips 1. The second component 20 also constitutes a flange in the case of a stator core 7 of a rotary motor 9 with an axial clearance type, constructed from iron chips 1 in the form of an SS / DR type.

[0138] The second component 20 is in the shape of a trapezoidal plate in this embodiment. A trapezoidal plate is defined by the cross-sectional shape of the second component 20 cut through a plane orthogonal to the Z-axis direction. The cross-section described above is the same in the Z-axis direction. Furthermore, in the case where the stator core 7 of an axially spaced rotary motor 9, constructed from iron chips 1, can be rectangular, the shape of the second component 20 can be rectangular.

[0139] Second component 20 Figures 1 to 3 As shown, a protrusion 21 is provided. The protrusion 21 extends outward from the circumferential surface 11 of the first component 10. The protrusion 21 may protrude outward from a portion of the circumferential surface 11 of the first component 10, or it may protrude outward from the circumferential surface 11 of the first component 10 throughout its entire circumference. In this embodiment, the protrusion 21 has a first protrusion 211 and a second protrusion 212. The first protrusion 211 extends in a first direction in the circumferential direction of the stator core 7. The second protrusion 212 extends in a second direction in the circumferential direction of the stator core 7. Alternatively, the protrusion 21 may not have a first protrusion 211 and a second protrusion 212, but may have portions extending in the X1 direction and portions extending in the X2 direction. In addition to the first protrusion 211 and the second protrusion 212, the protrusion 21 may also have portions extending in the X1 direction and portions extending in the X2 direction. In this case, the protrusion 21 is configured as an annular shape.

[0140] The protrusion lengths of the first protrusion 211 and the second protrusion 212 of the second component 20, in the case where the stator core 7 of the axially spaced rotary motor 9 constructed from iron chips 1 is longer than the protrusion lengths of the first protrusion 211 and the second protrusion 212 of the third component 30, as described later. The protrusion lengths of the first protrusion 211 and the second protrusion 212 of the second component 20, in the case where the stator core 7 of the axially spaced rotary motor 9 constructed from iron chips 1 is set to be the same as the protrusion lengths of the first protrusion 211 and the second protrusion 212 of the third component 30. The protrusion length refers to the length along a direction orthogonal to the circumferential surface 11 of the first component 10. When the circumferential surface 11 has a curved surface, the protrusion length refers to the length along the normal direction of the curved surface.

[0141] Second component 20 Figure 3 , Figure 5 As shown, the second component 20 has an outer peripheral surface 22, an inner peripheral surface 23, a first side surface 24a, a second side surface 24b, a first end surface 26, and a second end surface 27. The positional relationship of the outer peripheral surface 22, the inner peripheral surface 23, the first side surface 24a, and the second side surface 24b is as described above, and is the same as the positional relationship of the surfaces of the first component 10. The first end surface 26 and the second end surface 27 are arranged in a position opposite to each other. The first end surface 26 is located on the Z1 direction side. The second end surface 27 is located on the Z2 direction side. The second end surface 27 is located on the first component 10 side of the second component 20. The positional relationship of the first end surface 26 and the second end surface 27 is the same for the third component 30 described later.

[0142] The outer peripheral surface 22 is connected to the outer peripheral edge of the first side surface 24a, the outer peripheral edge of the second side surface 24b, the outer peripheral edge of the first end surface 26, and the outer peripheral edge of the second end surface 27. The outer peripheral surface 22 of the second component 20 is connected to the outer peripheral surface 12 of the first component 10. The inner peripheral surface 23 is connected to the inner peripheral edge of the first side surface 24a, the inner peripheral edge of the second side surface 24b, the inner peripheral edge of the first end surface 26, and the inner peripheral edge of the second end surface 27. The inner peripheral surface 23 of the second component 20 is connected to the inner peripheral surface 13 of the first component 10. The first side surface 24a and the second side surface 24b are connected to the outer peripheral surface 22 and the inner peripheral surface 23. The first end surface 26 is connected to the outer peripheral surface 22, the first side surface 24a, the second side surface 24b, and the inner peripheral surface 23. The second end surface 27 is connected to the outer peripheral surface 22, the first side surface 24a, the second side surface 24b, the inner peripheral surface 23, and the peripheral surface 11 of the first component 10.

[0143] The length between the first side surface 24a and the second side surface 24b of the outer peripheral surface 22 is longer than the length between the first side surface 24a and the second side surface 24b of the inner peripheral surface 23. The length between the first side surface 24a and the second side surface 24b of the outer peripheral surface 22 of the second component 20 is longer than the length between the first side surface 14a and the second side surface 14b of the peripheral surface 11 of the first component 10. The length between the first side surface 24a and the second side surface 24b of the inner peripheral surface 23 of the second component 20 is the same as the length between the first side surface 14a and the second side surface 14b of the inner peripheral surface 13 of the first component 10.

[0144] The outer peripheral surface 22 has a curved surface that protrudes towards the X2 direction in this embodiment. Furthermore, the outer peripheral surface 22 can be formed of a plane. The inner peripheral surface 23 has a curved surface that protrudes towards the X1 direction in this embodiment. Furthermore, the inner peripheral surface 23 can have a curved surface that protrudes towards the X2 direction, or it can be formed of a plane. The curvature radii of the outer peripheral surface 22 and the inner peripheral surface 23 can be the same or different from each other.

[0145] The first side surface 24a and the second side surface 24b each have a first parallel surface 241, a second parallel surface 242, and a first inclined surface 243. The first parallel surfaces 241 of the first side surface 24a and the second side surface 24b are parallel to each other. The second parallel surfaces 242 of the first side surface 24a and the second parallel surface 242 of the first side surface 24a are parallel to each other. The first parallel surface 241 and the second parallel surface 242 of the first side surface 24a are parallel to the X-axis direction of the iron chip 1. The first parallel surface 241 is connected to the outer peripheral surface 22. The second parallel surface 242 is connected to the inner peripheral surface 23. The first inclined surface 243 is connected to the first parallel surface 241 and the second parallel surface 242.

[0146] like Figure 5 As shown, the first tilt angle θ21 and the second tilt angle θ22 of the first tilted surface 243 are preferably 5° or more and 20° or less. If the first tilt angle θ21 and the second tilt angle θ22 are 5° or more and 20° or less, it is easy to configure the iron chip 1 in a ring shape and to easily construct the stator core 7. The first tilt angle θ21 and the second tilt angle θ22 are further preferably 5.5° or more and 18° or less, and particularly preferably 6° or more and 16° or less. The first tilt angle θ21 and the second tilt angle θ22 are preferably the same angle, but they can also be different angles. The first tilt angle θ21 refers to the angle formed between the extension surface E21 of the first parallel surface 241 of the first side surface 24a and the first tilted surface 243. The second tilt angle θ22 refers to the angle formed between the extension surface E22 of the first parallel surface 241 of the second side surface 24b and the first tilted surface 243.

[0147] In the case of a stator core 7 constructed from iron chips 1 in an axially spaced rotary motor 9 using a DS / SR configuration, the first iron chip 1 and the second iron chip 1 circumferentially adjacent to each other in the stator core 7 are in contact with the first side surface 24a and the second side surface 24b of the second component 20 of the first iron chip 1. In this case, the first inclined surface 243 of the first side surface 24a preferably has a portion 244 extending outward from the first imaginary surface V21. The first inclined surface 243 of the second side surface 24b preferably has a portion 244 extending outward from the second imaginary surface V22.

[0148] The first imaginary surface V21 is a plane connecting the first connecting portion and the second connecting portion on the first side surface 24a of the first protrusion 211. The first connecting portion of the first side surface 24a is the connection between the first parallel surface 241 and the first inclined surface 243 of the first side surface 24a. The second connecting portion of the first side surface 24a is the connection between the second parallel surface 242 and the inner peripheral surface 23 of the first side surface 24a. The second imaginary surface V22 is a plane connecting the first connecting portion and the second connecting portion on the second side surface 24b of the second protrusion 212. The first connecting portion of the second side surface 24b is the connection between the first parallel surface 241 and the first inclined surface 243 of the second side surface 24b. The second connecting portion of the second side surface 24b is the connection between the second parallel surface 242 and the inner peripheral surface 23 of the second side surface 24b. The first imaginary surface V21 and the second imaginary surface V22 are... Figure 5 It is represented by a double-dotted line extending diagonally across the paper.

[0149] The first inclined surface 243 of each of the first side surface 24a and the second side surface 24b has a protruding portion 244, which easily increases the magnetic circuit area of ​​the stator core 7. The reason is as follows. For example, in the case of a chip where the first side surface 24a and the second side surface 24b each have a first parallel surface 241, a second parallel surface 242, and a first inclined surface 243, but the first inclined surface 243 does not have a protruding portion 244, the situation becomes as follows. When this chip is arranged in a ring shape, if an attempt is made to bring the first side surface 24a of the first chip and the second side surface 24b of the second chip, which are circumferentially adjacent to each other in the stator core 7, into contact, the first corner of the first chip and the second corner of the second chip will come into contact. The first corner is the corner between the first side surface 24a and the inner circumferential surface 23. The second corner is the corner between the second side surface 24b and the inner circumferential surface 23. Therefore, it is impossible to make the first side surface 24a of the first chip 1 and the second side surface 24b of the second chip into sufficient contact. That is, the contact area of ​​the first side surface 24a of the first chip 1 and the second side surface 24b of the second chip 1 is reduced.

[0150] In contrast, the first side surface 24a of the aforementioned iron chip 1 has a first parallel surface 241, a second parallel surface 242, and a first inclined surface 243, the first inclined surface 243 having a portion 244 extending beyond the first imaginary surface V21. Similarly, the second side surface 24b of the aforementioned iron chip 1 has a first parallel surface 241, a second parallel surface 242, and a first inclined surface 243, the first inclined surface 243 having a portion 244 extending beyond the second imaginary surface V22. When the iron chip 1 is arranged in a ring shape, even if the first side surface 24a and the second side surface 24b of the first iron chip 1 come into contact, contact between the first corner portion of the first iron chip 1 and the second corner portion of the second iron chip 1 can be prevented. Therefore, sufficient contact between the first side surface 24a and the second side surface 24b of the first iron chip 1 is possible. That is, the contact area between the first side surface 24a and the second side surface 24b of the first iron chip 1 is increased.

[0151] In the case of a stator core 7 of a rotary motor 9 with an axial gap type constructed from iron chips 1 in a DS / SR configuration, as described above, the first iron chip 1 and the second iron chip 1 circumferentially adjacent to each other in the stator core 7 are in contact with the first side 24a of the second component 20 of the first iron chip 1 and the second side 24b of the second component 20 of the second iron chip 1. In this case, the first side 24a and the second side 24b of the iron chip 1 are each as follows: Figure 3 As shown, it is preferable to have steps 240 that can fit together. This makes it easier to increase the magnetic circuit area of ​​the stator core 7. The first and second circumferentially adjacent iron chips 1 and 1 are fitted together by steps 240 on the first side surface 24a of the first protrusion 211 of the second component 20 of the first iron chip 1 and steps 240 on the second side surface 24b of the second protrusion 212 of the second component 20 of the second iron chip 1. Therefore, the first and second iron chips 1 can be in sufficient contact, thus increasing the contact area between the circumferentially adjacent iron chips 1 of the stator core 7. The steps 240 on the first side surface 24a are provided on the first end face 26 side. The steps 240 on the first side surface 24a are configured to move away from the first side surface 14a of the first component 10 as it moves from the first end face 26 toward the second end face 27. On the other hand, the steps 240 on the second side surface 24b are provided on the second end face 27 side. The step 240 of the second side 24b is configured to move away from the first component 10 from the second end face 27 toward the first end face 26.

[0152] The first side surface 24a of the iron chip 1 is omitted from the illustration, but it may not be a step, but rather have at least one of a recess and a protrusion. The second side surface 24b may have at least one of a protrusion corresponding to the recess of the first side surface 24a and a recess corresponding to the protrusion of the first side surface 24a. That is, both the first side surface 24a and the second side surface 24b may have both recesses and protrusions. In addition, either the first side surface 24a or the second side surface 24b may have only a recess, and the other side may have only a protrusion. The number and shape of the recesses and protrusions are not particularly limited.

[0153] The first side surface 24a and the second side surface 24b of the iron chip 1 are not shown in the figure, but they may not be steps or uneven surfaces, but rather have second inclined surfaces that are connected to each other. For example, the second inclined surface of the first side surface 24a is inclined outward from the first end face 26 toward the second end face 27. Similarly, the second inclined surface of the second side surface 24b is inclined outward from the second end face 27 toward the first end face 26.

[0154] In the case of a stator core 7 of an axially spaced rotary motor 9 constructed from iron chips 1 in an SS / DR configuration, the iron chips 1 are arranged in a ring shape without contacting each other. In this case, the first side surface 24a and the second side surface 24b may each be free from any of the steps 240, recesses, protrusions, and second inclined surfaces that can fit together.

[0155] The corners between the first side surface 24a and the first end surface 26, and the corners between the first side surface 24a and the second end surface 27, are rounded. The corners between the second side surface 24b and the first end surface 26, and the corners between the second side surface 24b and the second end surface 27, are also rounded.

[0156] The first end face 26 is planar in the case of a stator core 7 of a rotary motor 9 with axial clearance type, constructed from iron chips 1 in a DS / SR configuration. In the case of a stator core 7 of a rotary motor 9 with axial clearance type, constructed from iron chips 1 in a SS / DR configuration, the first end face 26 can be planar or convex towards the Z1 direction. The iron chips 1 described above can be used to construct an axial clearance type rotary motor 9 with low noise and vibration. The reasons are as follows. The SS / DR type axial clearance type rotary motor 9... Figure 19 As shown, the stator 8 and rotor 90 are arranged opposite each other. The stator 8 is as follows... Figure 17 As shown, it has a stator core 7 and a coil 80. The stator core 7 is as follows: Figure 16 , Figure 17 As shown, this is a configuration where multiple iron chips 1 are arranged in a ring. The coil 80 is as follows... Figure 17As shown, the first component 10 is disposed in each iron chip 1. If the first end face 26 of the second component 20 of the iron chip 1 is convex, then in Figure 19 The axial clearance type rotary motor 9 shown can easily suppress abrupt changes in the magnetic flux of the rotor 90's magnet 95 on the iron chip 1. Therefore, the cogging torque is easily reduced. With low cogging torque, noise and vibration are less likely to increase.

[0157] The corners 28 between the first end face 26 and the inner peripheral face 23, and between the first end face 26 and the outer peripheral face 22, are preferably chamfered. These corners 28 are chamfered to prevent damage. These chamfers can be C-shaped or R-shaped.

[0158] The chamfer length of the corner 28 is preferably 0.1 mm or more and 0.5 mm or less. In the case of a C-shaped chamfer, where the corner 28 is a right triangle with its hypotenuse, the chamfer length refers to the length of the shorter side among the two sides other than the hypotenuse. In the case of an R-shaped chamfer, where the inflection points of the curved surface of the corner 28 and the surfaces connected to it are connected by straight lines to form a right triangle with its hypotenuse, the chamfer length refers to the length of the shorter side among the two sides other than the hypotenuse. When the chamfer length is within the above range, the corner 28 is less likely to be damaged. The chamfer length is further preferably 0.15 mm or more and 0.45 mm or less, and particularly preferably 0.2 mm or more and 0.4 mm or less.

[0159] [Third Component]

[0160] Third component 30 Figure 1 , Figure 3 As shown, the third component 30 is a plate-shaped component disposed on the second end side in the Z-axis direction of the first component 10. The third component 30 is configured with a flange in either the case where the stator core 7 of the rotary motor 9 is constructed from the iron chip 1 in the DS / SR type or the case where the stator core 7 of the rotary motor 9 is constructed in the SS / DR type.

[0161] The third component 30 is in the shape of a trapezoidal plate in this embodiment. A trapezoidal plate is defined as a cross-section of the third component 30 cut through a plane orthogonal to the Z-axis direction. The cross-section described above is the same in the Z-axis direction. Alternatively, the third component 30 can also be a rectangular plate. For example, the iron chip 1 may have a first component 10 that is a trapezoidal column, and at least one of the second component 20 and the third component 30 that is a rectangular plate.

[0162] Third component 30 Figures 1 to 3As shown, a protrusion 31 is provided. The protrusion 31 extends outward from the circumferential surface 11 of the first component 10. The protrusion 31 may protrude outward from a portion of the circumferential surface 11 of the first component 10, or it may protrude outward from the circumferential surface 11 of the first component 10 throughout its entire circumference. In this embodiment, the protrusion 31 has a first protrusion 311 and a second protrusion 312. The first protrusion 311 extends towards a first direction in the circumferential direction of the stator core 7. The second protrusion 312 extends towards a second direction in the circumferential direction of the stator core 7. Alternatively, the protrusion 31 may not have a first protrusion 311 and a second protrusion 312, but may have at least one of a portion extending towards the X1 direction and a portion extending towards the X2 direction. In addition to the first protrusion 311 and the second protrusion 312, the protrusion 31 may also have a portion extending towards the X1 direction and a portion extending towards the X2 direction. In this case, the protrusion 31 is configured as an annular shape.

[0163] The protrusion lengths of the first protrusion 311 and the second protrusion 312 of the third component 30, as described above, are shorter than the protrusion lengths of the first protrusion 311 and the second protrusion 312 of the second component 20 in the case of a stator core 7 provided with an axially gap type rotary motor 9 constructed from iron chips 1 in a DS / SR manner, as described above. The protrusion lengths of the first protrusion 311 and the second protrusion 312 of the third component 30, as described above, are set to be the same as the protrusion lengths of the first protrusion 211 and the second protrusion 212 of the second component 20 in the case of a stator core 7 provided with an axially gap type rotary motor 9 constructed from iron chips 1 in an SS / DR manner, as described above.

[0164] Third component 30 Figure 6 As shown, the component has an outer peripheral surface 32, an inner peripheral surface 33, a first side surface 34a, a second side surface 34b, a first end surface 36, and a second end surface 37. The positional relationship of the outer peripheral surface 32, the inner peripheral surface 33, the first side surface 34a, and the second side surface 34b is as described above, and is the same as the positional relationship of the surfaces of the first component 10. The positional relationship of the first end surface 36 and the second end surface 37 is as described above, and is the same as the positional relationship of the surfaces of the second component 20.

[0165] The outer peripheral surface 32 is connected to the outer peripheral edge of the first side surface 34a, the outer peripheral edge of the second side surface 34b, the outer peripheral edge of the first end surface 36, and the outer peripheral edge of the second end surface 37. The outer peripheral surface 32 of the third component 30 is connected to the outer peripheral surface 12 of the first component 10. The inner peripheral surface 33 is connected to the inner peripheral edge of the first side surface 34a, the inner peripheral edge of the second side surface 34b, the inner peripheral edge of the first end surface 36, and the inner peripheral edge of the second end surface 37. The inner peripheral surface 33 of the third component 30 is connected to the inner peripheral surface 13 of the first component 10. The first side surface 34a and the second side surface 34b are connected to the outer peripheral surface 32 and the inner peripheral surface 33. The first end surface 36 is connected to the outer peripheral surface 32, the first side surface 34a, the second side surface 34b, and the inner peripheral surface 33. The second end surface 37 is connected to the outer peripheral surface 32, the first side surface 34a, the second side surface 34b, the inner peripheral surface 33, and the peripheral surface 11 of the first component 10.

[0166] The length between the first side surface 34a and the second side surface 34b of the outer peripheral surface 32 is longer than the length between the first side surface 34a and the second side surface 34b of the inner peripheral surface 33. The length between the first side surface 34a and the second side surface 34b of the outer peripheral surface 32 of the third component 30 is longer than the length between the first side surface 14a and the second side surface 14b of the outer peripheral surface 12 of the first component 10. The length between the first side surface 34a and the second side surface 34b of the outer peripheral surface 32 of the third component 30 is shorter than the length between the first side surface 24a and the second side surface 24b of the outer peripheral surface 22 of the second component 20. The length between the first side surface 34a and the second side surface 34b of the inner peripheral surface 33 of the third component 30 is the same as the length between the first side surface 14a and the second side surface 14b of the inner peripheral surface 13 of the first component 10. That is, the length between the first side surface 14a and the second side surface 14b of the inner peripheral surface 13 of the first component 10, the length between the first side surface 24a and the second side surface 24b of the inner peripheral surface 23 of the second component 20, and the length between the first side surface 34a and the second side surface 34b of the inner peripheral surface 33 of the third component 30 are the same as each other.

[0167] The outer peripheral surface 32 has a curved surface that protrudes towards the X2 direction. Alternatively, the outer peripheral surface 32 can be composed of a plane. The inner peripheral surface 33 has a curved surface that protrudes towards the X1 direction. Alternatively, the inner peripheral surface 33 can also have a curved surface that protrudes towards the X2 direction, and can also be composed of a plane. The curvature radii of the outer peripheral surface 32 and the inner peripheral surface 33 can be the same or different from each other.

[0168] At least two of the outer peripheral surfaces 12, 22, and 32 may have the same radius of curvature. Alternatively, all three may have the same radius of curvature, or all three may have different radii.

[0169] The first side surface 34a and the second side surface 34b each have a first parallel surface 341, a second parallel surface 342, and a first inclined surface 343. The first parallel surface 341 of the first side surface 34a and the second side surface 34b are parallel to each other. The second parallel surface 342 of the first side surface 34a and the second parallel surface 342 of the second side surface 34b are parallel to each other. The first parallel surface 341 and the second parallel surface 342 of the first side surface 34a are parallel to the X-axis direction of the iron chip 1. The first parallel surface 341 is connected to the outer peripheral surface 32. The second parallel surface 342 is connected to the inner peripheral surface 33. The first inclined surface 343 is connected to the first parallel surface 341 and the second parallel surface 342.

[0170] like Figure 6 As shown, the first tilt angle θ31 and the second tilt angle θ32 of the first tilted surface 343 are preferably 5° or more and 20° or less. If the first tilt angle θ31 and the second tilt angle θ32 are 5° or more and 20° or less, the density fluctuation of the iron chip 1 can be suppressed. The first tilt angle θ31 and the second tilt angle θ32 are further preferably 5.5° or more and 18° or less, and particularly preferably 6° or more and 16° or less. The first tilt angle θ31 and the second tilt angle θ32 are preferably the same angle, but they can also be different angles. The first tilt angle θ31 refers to the angle formed between the extension surface E31 of the first parallel surface 341 of the first side surface 34a and the first tilted surface 343. The second tilt angle θ32 refers to the angle formed between the extension surface E32 of the first parallel surface 341 of the second side surface 34b and the first tilted surface 343.

[0171] At least two of the first tilt angles θ11, θ21, and θ31 can be the same. At least two of the second tilt angles θ12, θ22, and θ32 can be the same. Alternatively, all three of the first tilt angles θ11, θ21, and θ31 can be the same. Similarly, all three of the second tilt angles θ12, θ22, and θ32 can be the same. Furthermore, all three of the first tilt angles θ11, θ21, and θ31 can be different. Similarly, all three of the second tilt angles θ12, θ22, and θ32 can be different.

[0172] The corners between the first side surface 34a and the first end surface 36, and the corners between the first side surface 34a and the second end surface 37, are rounded. The corners between the second side surface 34b and the first end surface 36, and the corners between the second side surface 34b and the second end surface 37, are also rounded.

[0173] In any case, such as when the first end face 36 is constructed from the iron chip 1 in the case of the stator core 7 of the rotary motor 9 with axial gap in DS / SR mode and the case of the stator core 7 of the rotary motor 9 with axial gap in SS / DR mode, it can be as follows: Figure 3 As shown by the solid lines, it can be composed of planes, or as... Figure 3 The first end face 36 is convex, as shown by the double-dotted line pointing towards the Z2 direction. If the first end face 36 is convex, an axially backlash type rotary motor 9 with low noise and vibration can be constructed. The reason is as follows. The axially backlash type rotary motor 9, as shown... Figure 18 or Figure 19 As shown, the stator 8 and rotor 90 are arranged opposite each other. The stator 8 is as follows: Figure 17 As shown, it has a stator core 7 and a coil 80. The stator core 7 is as follows: Figure 16 , Figure 17 As shown, multiple iron chips 1 are arranged in a ring shape. The coil 80 is as follows... Figure 17 As shown, the first component 10 is disposed in each iron chip 1. Figure 3 As shown by the double-dotted line, the first end face 36 of the third component 30 of the iron chip 1 is convex, thereby... Figure 18 , Figure 19 The axial clearance type rotary motor 9 shown can easily suppress abrupt changes in the magnetic flux of the rotor 90's magnet 95 on the iron chip 1. Therefore, the cogging torque is easily reduced. With low cogging torque, noise and vibration are less likely to increase.

[0174] The corner 38 between the first end face 36 and the outer peripheral face 32, and the corner 38 between the first end face 36 and the inner peripheral face 33, are preferably chamfered. These corners 38 are chamfered to prevent damage. These chamfers can be C-shaped or R-shaped. The chamfer length of the corner 38 is similar to that of the corner 28, preferably 0.1 mm or more and 0.5 mm or less, more preferably 0.15 mm or more and 0.45 mm or less, and particularly preferably 0.2 mm or more and 0.4 mm or less.

[0175] [seam]

[0176] The first joint between the protrusion 21 of the second component 20 and the peripheral surface 11 of the first component 10, and the second joint between the protrusion 31 of the third component 30 and the peripheral surface 11 of the first component 10, are as follows: Figure 3 As shown, the corners are rounded. In this configuration, the first seam has a seam between the first protrusion 211 of the second component 20 and the peripheral surface 11 of the first component 10, and a seam between the second protrusion 212 of the second component 20 and the peripheral surface 11 of the first component 10. These seams are rounded. The second seam has a seam between the first protrusion 311 of the third component 30 and the peripheral surface 11 of the first component 10, and a seam between the second protrusion 312 of the third component 30 and the peripheral surface 11 of the first component 10. These seams are rounded. Each seam has a rounded corner shape, thereby making it less likely for the ferrite chip 1 to be damaged starting from the aforementioned seams.

[0177] The bending radius of the first joint and the bending radius of the second joint are preferably 0.2 mm or more and 4.0 mm or less. A bending radius of 0.2 mm or more for both the first and second joints reduces the load on the mold during the manufacture of the iron chip 1. A bending radius of 4.0 mm or less for both the first and second joints reduces the load on the mold during the manufacture of the iron chip 1. Figure 17 When constructing the stator 8 described later, it is easy to wind the coil 80, thus making it easier to increase the number of turns of the coil 80. The bending radius of the first joint and the bending radius of the second joint are further preferably 0.3 mm or more and 3.0 mm or less, and particularly preferably 0.5 mm or more and 2.0 mm or less. The bending radius of the first joint and the bending radius of the second joint may be the same as each other or different from each other.

[0178] [Area Ratio]

[0179] The combined area of ​​the outer peripheral surfaces 12, 22, and 32 of the first component 10, the second component 20, and the third component 30 is preferably more than one and less than four times the combined area of ​​the inner peripheral surfaces 13, 23, and 33 of the first component 10, the second component 20, and the third component 30. A chip 1 with a combined area of ​​outer peripheral surfaces 12, 22, and 32 that is more than one times the combined area of ​​inner peripheral surfaces 13, 23, and 33 is easily configured into a ring shape, facilitating the construction of the stator core 7. A chip 1 with a combined area of ​​outer peripheral surfaces 12, 22, and 32 that is less than four times the combined area of ​​inner peripheral surfaces 13, 23, and 33 is easier to manufacture. A relatively large combined area of ​​inner peripheral surfaces 13, 23, and 33 results in a large area being pushed by the lower punch 55 when the chip 1 is pulled out of the mold 5. Therefore, damage to the chip 1 is easily suppressed when it is pulled out of the mold 5. The total area of ​​the outer circumferential surfaces 12, 22, and 32 is preferably more than 1.2 times and less than 3.8 times the total area of ​​the inner circumferential surfaces 13, 23, and 33, and is particularly preferably more than 1.5 times and less than 3.5 times.

[0180] [Material]

[0181] Powder-pressed molded body such as Figure 8 , Figure 9 As shown, a plurality of soft magnetic particles 40 are present. The pressed powder molded body is preferably composed of an assembly of a plurality of coated soft magnetic particles 40. The coated soft magnetic particles 40 have soft magnetic particles 40 and an insulating coating 41 covering the surface of the soft magnetic particles 40. If an insulating coating 41 is formed, electrical insulation between the soft magnetic particles 40 can be easily ensured by the insulating coating 41. Therefore, iron loss of the pressed powder molded body caused by eddy current loss can be reduced. The material of the soft magnetic particles 40 is, for example, pure iron or iron-based alloy. Pure iron refers to a material with a Fe (iron) purity of 99% by mass or more. Iron-based alloys contain at least one element of Si (silicon) and Al (aluminum), with the remainder consisting of Fe and unavoidable impurities. Examples of iron-based alloys are at least one selected from the group consisting of Fe-Si alloys, Fe-Al alloys, and Fe-Si-Al alloys. Examples of Fe-Si alloys are, for example, silicon steel. Examples of Fe-Si-Al alloys are, for example, iron-silicon-aluminum. The aforementioned material is relatively soft, therefore the soft magnetic particles 40 are easily deformed during the molding and pressing of the powder body. Therefore, the iron chip 1 has high density and excellent dimensional accuracy. Examples of insulating coatings 41 include phosphate coatings and silica coatings.

[0182] [Shape of soft magnetic particles]

[0183] The compressed powder body is formed by compressing soft magnetic powder having multiple soft magnetic particles 40. Alternatively, the compressed powder body is formed by compressing coated soft magnetic powder having multiple coated soft magnetic particles 4. That is, the soft magnetic particles 40 are flat in shape. The soft magnetic particles 40 have a long axis and a short axis in the first cross-section of the first component 10, the second cross-section of the second component 20, and the third cross-section of the third component 30, which will be described later.

[0184] [First average aspect ratio]

[0185] exist Figure 7 The first cross-section of the first component 10 shown is shown. Figure 8 The first average aspect ratio of the soft magnetic particles 40 shown is 1.2 or greater. The first cross-section is a cross-section along both the X-axis and Z-axis directions. The first average aspect ratio is the ratio of the average length L11 to the average length L12 of the first cross-section, L12 / L11. The average length L11 is the average length of the soft magnetic particles 40 along the X-axis direction. The average length L12 is the average length of the soft magnetic particles 40 along the Z-axis direction. The larger the first average aspect ratio, the longer the length of the soft magnetic particles 40 along the Z-axis direction is compared to its length along the X-axis direction in the first cross-section of the first component 10.

[0186] A first cross-section of the first component 10 is taken as a square first field of view. The first field of view is obtained by having a pair of first sides along the Z-axis and a pair of second sides along the X-axis. The first average aspect ratio of the soft magnetic particles 40 satisfies 1.2 or more, thereby reducing the number of soft magnetic particles 40 arranged side-by-side in the Z-axis direction compared to the number of soft magnetic particles 40 arranged side-by-side in the X-axis direction within the first field of view. That is, the number of grain boundaries dividing the Z-axis direction is small within the first field of view. A grain boundary refers to the boundary between adjacent soft magnetic particles.

[0187] The first average aspect ratio is further preferably 1.25 or higher, and particularly preferably 1.3 or higher. An upper limit for the first average aspect ratio is, for example, around 1.7. That is, the first average aspect ratio is preferably 1.2 or higher and 1.7 or lower, further preferably 1.25 or higher and 1.6 or lower, and particularly preferably 1.3 or higher and 1.5 or lower.

[0188] The average lengths L11 and L12 are determined as follows: In the first cross-section, a first imaginary line is drawn along the X-axis. The length of the first imaginary line is 1000 μm. The number of soft magnetic particles 40 present on the first imaginary line is counted. The length of the first imaginary line is divided by the total number of soft magnetic particles 40 counted. The value obtained by this division is taken as the length L11. Similarly, in the first cross-section, a second imaginary line is drawn along the Z-axis. The length of the second imaginary line is 1000 μm. The number of soft magnetic particles 40 present on the second imaginary line is counted. The length of the second imaginary line is divided by the total number of soft magnetic particles 40 counted. The value obtained by this division is taken as the length L12.

[0189] [Second average aspect ratio]

[0190] exist Figure 5 The second cross-section of the second component 20 shown has a second average aspect ratio of 1.2 or higher for the soft magnetic particles 40. This second cross-section is orthogonal to the Z-axis direction. The second average aspect ratio is the ratio of the average length L21 to the average length L22 of the second cross-section, L22 / L21. The average length L21 is the average length of the soft magnetic particles 40 along the X-axis direction. The average length L22 is the average length of the soft magnetic particles 40 along the circumference of the stator core 7. The larger the second average aspect ratio, the longer the length of the soft magnetic particles 40 along the circumference of the stator core 7 is compared to their length along the X-axis direction in the second cross-section of the second component 20.

[0191] In the second cross-section of the second component 20, a square second observation field is taken. The second observation field is obtained by having a pair of first sides along the X-axis and a pair of second sides along the Y-axis. The second average aspect ratio of the soft magnetic particles 40 satisfies 1.2 or more, thereby reducing the number of soft magnetic particles 40 arranged side-by-side in the circumferential direction of the stator core 7 compared to the number of soft magnetic particles 40 arranged side-by-side in the X-axis direction in the second observation field. That is, the number of grain boundaries dividing the circumference of the stator core 7 is reduced in the second observation field. The appropriate numerical range of the second average aspect ratio is the same as the appropriate numerical range of the first average aspect ratio described above.

[0192] The average lengths L21 and L22 are determined as follows: In the second cross-section, a first imaginary line is drawn along the X-axis. The length of the first imaginary line is 1000 μm. The number of soft magnetic particles 40 present on the first imaginary line is counted. The length of the first imaginary line is divided by the total number of soft magnetic particles 40 counted. The value obtained by this division is taken as the length L21. Similarly, in the second cross-section, a second imaginary line is drawn along the circumference of the stator core 7. The second imaginary line is an arc protruding in the X2 direction. In this case, the second imaginary line is an arc concentric with the outer periphery of the second component 20. The length of the second imaginary line is 1000 μm. The number of soft magnetic particles 40 present on the second imaginary line is counted. The length of the second imaginary line is divided by the total number of soft magnetic particles 40 counted. The value obtained by this division is taken as the length L22.

[0193] [Third average aspect ratio]

[0194] exist Figure 6 The third cross-section of the third component 30 shown has a third average aspect ratio of 1.2 or higher for the soft magnetic particles. This third cross-section is orthogonal to the Z-axis. The third average aspect ratio is the ratio of the average length L31 to the average length L32 of the third cross-section, L32 / L31. The average length L31 is the average length of the soft magnetic particles 40 along the X-axis. The average length L32 is the average length of the soft magnetic particles 40 along the circumference of the stator core 7. The larger the third average aspect ratio, the longer the length of the soft magnetic particles 40 along the circumference of the stator core 7 is compared to their length along the X-axis in the third cross-section of the third component 30.

[0195] In the third cross-section of the third component 30, a square third observation field of view, identical to the second observation field of view described above, is taken. The third average aspect ratio of the soft magnetic particles 40 satisfies 1.2 or higher, thereby reducing the number of soft magnetic particles 40 arranged circumferentially in the stator core 7 compared to the number of soft magnetic particles 40 arranged side-by-side in the X-axis direction within the third observation field of view. That is, the number of grain boundaries dividing the stator core 7 circumferentially within the third observation field of view is reduced. The appropriate numerical range of the third average aspect ratio is the same as the appropriate numerical range of the first average aspect ratio described above. The methods for calculating the average length L31 and average length L32 are the same as those for calculating the average length L21 and average length L22.

[0196] [Average Particle Size]

[0197] The average particle size of the soft magnetic particles 40 is preferably 30 μm or more. When the average particle size of the soft magnetic particles 40 is 30 μm or more, the relative permeability is easily increased. The iron chip 1 having these soft magnetic particles 40 exhibits low loss. Therefore, the iron chip 1 can easily be used to construct a low-loss axially gap type rotary motor 9. The average particle size of the soft magnetic particles 40 is further exemplified as 40 μm or more, and particularly 50 μm or more. The upper limit of the average particle size of the soft magnetic particles 40 is, for example, 500 μm. When the average particle size of the soft magnetic particles 40 is 500 μm or less, the eddy current loss of the soft magnetic particles 40 themselves is easily reduced. The iron chip 1 having these soft magnetic particles 40 can easily be used to construct an axially gap type rotary motor 9 with excellent magnetic properties. That is, the average particle size of the soft magnetic particles 40 is exemplified as 30 μm or more and 500 μm or less, further exemplified as 40 μm or more and 450 μm or less, and particularly 50 μm or more and 400 μm or less.

[0198] The average particle size of the soft magnetic particles 40 was determined as follows: A cross-section of the iron chip 1 was observed using a SEM (Scanning Electron Microscope). The cross-section was prepared using a cross-section polishing apparatus. This cross-section was set along both the X-axis and Z-axis directions. Observation images of the cross-section were obtained. The SEM magnification was set to 150x or higher and 500x or lower. The size of the observation image was 800μm × 800μm, for example. At least 50 observation images were obtained. One observation image could be obtained for each cross-section, or multiple observation images could be obtained for each cross-section. Image processing was performed on each obtained observation image to extract the contours of the soft magnetic particles. Image processing, for example, binarization processing, was performed. The area of ​​each soft magnetic particle present in each observation image was calculated. The diameter of a circle having the same area as each area was calculated. The average value of all calculated diameters was calculated. This average value was set as the average particle size of the soft magnetic particles 40. For example, more than 200 measurements can be used to determine the average particle size.

[0199] [Magnetic Circuit]

[0200] Constructing, for example, using iron chip 1 Figure 18 When using an axially spaced rotary motor 9 as shown, the magnetic flux passes through the iron chip 1. For example, the magnetic flux... Figure 10As indicated by the white arrows, the magnetic flux passes through the second component 20, the first component 10, and the third component 30 in sequence. Alternatively, regarding the magnetic flux, although the white arrows are omitted, it passes through the third component 30, the first component 10, and the second component 20 in sequence. The magnetic flux passing through the second component 20 is along the surface direction of the second component 20. That is, the magnetic flux passing through the second component 20 is along the circumference of the stator core 7. The magnetic flux passing through the first component 10 is along the Z-axis direction. The magnetic flux passing through the third component 30 is along the surface direction of the third component 30. That is, the magnetic flux passing through the third component 30 is along the circumference of the stator core 7. The magnetic flux passing through the second component 20 is parallel to the magnetic flux passing through the third component 30. The magnetic flux passing through the second component 20 and the magnetic flux passing through the first component 10 are in different directions from each other.

[0201] As described above, in the first cross-section of the first component 10, the first average aspect ratio of the soft magnetic particles 40 is 1.2 or higher. Therefore, in the first cross-section, the length of the soft magnetic particles 40 along the magnetic flux is longer than its length along the direction orthogonal to the magnetic flux. That is, in the first field of view of the first cross-section, the number of soft magnetic particles 40 arranged side by side in the direction of the magnetic flux is less than the number of soft magnetic particles 40 arranged side by side in the direction orthogonal to the direction of the magnetic flux. In the first field of view, the number of grain boundaries that divide along the direction of the magnetic flux is less.

[0202] Furthermore, as described above, in the second cross-section of the second component 20, the second average aspect ratio of the soft magnetic particles 40 is 1.2 or higher. Therefore, in the second cross-section, the length of the soft magnetic particles 40 along the magnetic flux is longer than its length along the direction orthogonal to the magnetic flux. That is, in the second field of view described above in the second cross-section, the number of soft magnetic particles 40 arranged side by side in the direction of the magnetic flux is less than the number of soft magnetic particles 40 arranged side by side in the direction orthogonal to the direction of the magnetic flux. In the second field of view, the number of grain boundaries that divide along the direction of the magnetic flux is less.

[0203] Furthermore, as described above, in the third cross-section of the third component 30, the third average aspect ratio of the soft magnetic particles 40 is 1.2 or higher. Therefore, in the third cross-section, the length of the soft magnetic particles 40 along the magnetic flux is longer than its length along the direction orthogonal to the magnetic flux. That is, in the aforementioned third field of view of the third cross-section, the number of soft magnetic particles 40 arranged side by side along the direction of the magnetic flux is less than the number of soft magnetic particles 40 arranged side by side in the direction orthogonal to the direction of the magnetic flux. In the third field of view, the number of grain boundaries that divide along the direction of the magnetic flux is less.

[0204] As described below, when the raw material powder filling the mold cavity of the die is pressurized and formed by the upper and lower punches, the pressing direction and the pulling direction are set along the X-axis direction of the iron chip 1, thereby enabling manufacturing.

[0205] Here, we examine the case where the pressing and pulling directions are set along the axial direction of the stator core of the iron chip, unlike the pressing and pulling directions used in manufacturing the iron chip 1 of this method. In this case, it is impossible to manufacture the iron chip 1 with the first component 10, the second component 20, and the third component 30 as in this method. The reason is that, as mentioned above, the second component 20 and the third component 30 each have protrusions 21 and 31, respectively, and therefore the protrusions 21 and 31 hook onto the inner circumferential surface of the die cavity, preventing the iron chip 1 from being pulled out of the die. If the iron chip has the first and second components but not the third component, it can be manufactured even if the pressing and pulling directions are set along the axial direction of the stator core of the iron chip. The iron chip manufactured with the first and second components but not the third component, and with the pressing and pulling directions set along the axial direction of the stator core of the iron chip, is a conventional iron chip.

[0206] In the existing first component of the iron chip, a first cross-section identical to the first cross-section of the first component of the iron chip 1 of this embodiment is taken. Furthermore, in the existing second component of the iron chip, a second cross-section identical to the second cross-section of the second component of the iron chip 1 of this embodiment is taken.

[0207] In the first cross-section of the first component of the existing iron chip, unlike the first cross-section of the first component 10 of the iron chip 1 of this embodiment, the length of the soft magnetic particles along the axial direction of the stator core is shorter than the length along the radial direction of the stator core. In the first cross-section of the existing iron chip, a square first observation field of view, identical to the first observation field of view described above, is taken. In the first observation field of the existing iron chip, unlike the first observation field of the iron chip 1 of this embodiment, the number of soft magnetic particles arranged side-by-side in the axial direction of the stator core is greater than the number of soft magnetic particles arranged side-by-side in the radial direction of the stator core. That is, in the first observation field of the existing iron chip, unlike the first observation field of the iron chip 1 of this embodiment, the number of grain boundaries dividing the axial direction of the stator core is greater. The magnetic flux passing through the first component of the existing iron chip is similar to that of the second component 20 of the iron chip 1 of this embodiment, along the axial direction of the stator core. That is, in the first observation field of the existing iron chip, unlike the first observation field of the iron chip 1 of this embodiment, the number of soft magnetic particles arranged side-by-side in the direction of the magnetic flux is greater than the number of soft magnetic particles arranged side-by-side in the direction orthogonal to the direction of the magnetic flux. The first field of view of the existing iron chip is different from the first field of view of the iron chip 1 in this method, and the number of grain boundaries divided along the direction of magnetic flux is greater.

[0208] In the second cross-section of the second component of the existing iron chip, unlike the second cross-section of the second component 20 of the iron chip 1 of this embodiment, the length of the soft magnetic particles along the circumferential direction of the stator core and the length along the radial direction of the stator core are the same. In the second cross-section of the existing iron chip, a square second observation field of view, identical to the second observation field of view described above, is taken. In the second observation field of the existing iron chip, unlike the second observation field of the iron chip 1 of this embodiment, the number of soft magnetic particles arranged side-by-side in the circumferential direction of the stator core and the number of soft magnetic particles arranged side-by-side in the radial direction of the stator core are the same. That is, in the second observation field of the existing iron chip, unlike the second observation field of the iron chip 1 of this embodiment, the number of grain boundaries dividing the stator core circumferentially and the number of grain boundaries dividing the stator core radially are the same. The magnetic flux passing through the second component of the existing iron chip is, in the same manner as the second component 20 of the iron chip 1 of this embodiment, along the circumferential direction of the stator core. That is, in the second field of view of the existing iron chip, unlike the second field of view of the iron chip 1 of this method, the number of soft magnetic particles arranged side by side in the direction of magnetic flux and the number of soft magnetic particles arranged side by side in the direction orthogonal to the direction of magnetic flux are the same. In the second field of view of the existing iron chip, unlike the second field of view of the iron chip 1 of this method, the number of grain boundaries segmented along the direction of magnetic flux and the number of grain boundaries segmented in the direction orthogonal to the direction of magnetic flux are the same.

[0209] Compared to existing iron chip first components, the first component 10 of the present invention has fewer grain boundaries that divide the magnetic flux direction. These grain boundaries become magnetic gaps. The more magnetic gaps there are, the greater the magnetic reluctance becomes. Therefore, the first component 10 of the present invention facilitates magnetic flux passage compared to existing iron chip first components. The second component 20 of the present invention has the same ease of magnetic flux passage as the second component of existing iron chips. Thus, the present invention facilitates magnetic flux passage compared to existing iron chips. Therefore, the present invention facilitates the construction of an axially gap type rotary motor 9 with excellent magnetic properties compared to existing iron chips. The more iron chips that constitute the stator core of the axially gap type rotary motor 9, the easier it is to construct an axially gap type rotary motor 9 with even better magnetic properties compared to existing iron chips. As described above, when the proportion of the second height H10 to the first height H1 is 80% or more, the proportion of the first component 10 and the third component 30 tends to increase in the area excluding the second component 20 occupied by the iron chip 1. Therefore, when the second height H10 in this embodiment, excluding the second component 20 occupied by the iron chip 1, is constant, compared with the existing iron chip, the iron chip 1 in this embodiment can more easily construct an axially gap type rotary motor 9 with excellent magnetic properties.

[0210] [Relative density]

[0211] The relative density of the pressed powder molded body is preferably 85% or higher. Pressed powder molded bodies with a relative density of 85% or higher exhibit excellent magnetic properties, such as saturation magnetic flux density, and mechanical properties, such as strength. The relative density of the pressed powder molded body is further preferably 90% or higher, and particularly preferably 93% or higher. Examples of pressed powder molded bodies with a relative density less than 100% are also mentioned. "Relative density" refers to the ratio (%) of the actual density of the pressed powder molded body to the true density of the soft magnetic particles constituting the pressed powder molded body.

[0212] [Difference in relative density]

[0213] The difference in relative density between the first, second, and third portions of the iron chip 1 is preferably 5.0% or less. A small difference in relative density results in substantially uniform physical properties, such as magnetic properties, within the iron chip 1. The smaller the difference in relative density between the first, second, and third portions, the better. More preferably, the difference in relative density between the first, second, and third portions is 4.0% or less, and particularly preferably 3.0% or less. Here, as... Figure 2 As shown, the portion on the first circumferential direction side of the portion in which the iron chip 1 is divided into three parts by an imaginary surface Va along the second parallel plane of the first side and an imaginary surface Vb along the second parallel plane of the second side is designated as the first portion, the portion on the second circumferential direction side is designated as the second portion, and the portion between the first portion and the second portion is designated as the third portion.

[0214] Preferably, the difference in relative density between the component with the highest relative density and the component with the lowest relative density among the first component 10, the second component 20, and the third component 30 is 5.0% or less. Because the difference in relative density of the iron chip 1 is small, the physical properties, such as magnetic properties, are substantially uniform within the iron chip 1. The smaller the difference in relative density between the component with the highest relative density and the component with the lowest relative density, the better. More preferably, the difference in relative density between the component with the highest relative density and the component with the lowest relative density is 4.0% or less, and particularly preferably 3.0% or less.

[0215] Preferably, the difference in relative density between the first part and the second and third parts is 5.0% or less, and the difference in relative density between the part with the highest relative density and the part with the lowest relative density is 5.0% or less.

[0216] [Effects]

[0217] In this method, the iron chip 1 allows magnetic flux to easily pass through any of the first component 10, the second component 20, and the third component 30, thus facilitating the construction of an axially spaced rotary motor 9 with excellent magnetic properties. Furthermore, the first component 10, the second component 20, and the third component 30 of the iron chip 1 in this method are constructed from a single-piece pressed powder molding body, resulting in excellent productivity.

[0218] [Manufacturing method of iron chips]

[0219] The method for manufacturing an iron chip according to Embodiment 1 includes a filling step and a molding step. In the filling step, raw material powder is filled into a mold 5. The raw material powder comprises multiple soft magnetic particles in a spherical shape. In the molding step, the raw material powder within the mold 5 is compressed to form a molded body. The method for manufacturing an iron chip according to this embodiment can manufacture the iron chip 1 according to this embodiment. First, referring to… Figures 11 to 14 The mold 5 will be explained, and then each process will be explained.

[0220] [Mold]

[0221] The mold 5 has a die 50, an upper punch 54, and a lower punch 55. The die 50 and the lower punch 55 form a cavity. The cavity is filled with raw material powder.

[0222] (die)

[0223] The die 50 has a cavity 50h. The cavity 50h is configured with the upper punch 54 and the lower punch 55 facing each other. The inner circumferential shape of the cavity 50h corresponds to the shape of the iron chip 1. The upper punch 54 can be driven independently in the vertical direction relative to the die 50. The lower punch 55 can be driven independently in the vertical direction relative to the die 50.

[0224] The mold cavity 50h has Figure 11 , Figure 12 The first hole 51 shown Figure 11 , Figure 13 The second hole 52 shown and Figure 11 , Figure 14 The third hole 53 is shown. Figure 11 The opening edge of the upper punch 54 side of the cavity 50h of the die 50 is shown. Figure 11 For clarity, the die 50 is marked with a shaded line. Figures 12 to 14 This is a cross-sectional view showing the state in which raw material powder filled in the cavity is pressurized and formed by the upper punch 54 and the lower punch 55. Figure 12 The cut position of the sectional view is equivalent to Figure 11 The position indicated by the XII-XII cut line. Figure 13 The cut position of the sectional view is equivalent to Figure 11 The position indicated by the XIII-XIII cut line. Figure 14The cut position of the sectional view is equivalent to Figure 11 The position indicated by the XIV-XIV cut line.

[0225] The first hole 51 has an inner peripheral surface forming the first side surface 14a and the second side surface 14b of the first component 10. The second hole 52 has an inner peripheral surface forming the first side surface 24a, the second side surface 24b, the first end surface 26, and the second end surface 27 of the second component 20. The third hole 53 has an inner peripheral surface forming the first side surface 34a, the second side surface 34b, the first end surface 36, and the second end surface 37 of the third component 30. The first hole 51, the second hole 52, and the third hole 53 are formed in a series in a direction orthogonal to the direction opposite to the upper punch 54 and the lower punch 55. Specifically, the second hole 52 is connected to the first end side of the first hole 51 in the above-mentioned orthogonal direction. In addition, the third hole 53 is connected to the second end side of the first hole 51 in the above-mentioned orthogonal direction.

[0226] The first hole portion 51 has a first straight portion 511, a second straight portion 512, and a tapered portion 513. The first straight portion 511, the tapered portion 513, and the second straight portion 512 are formed sequentially from the upper punch 54 side to the lower punch 55 side. Similarly, the second hole portion 52 has a first straight portion 521, a second straight portion 522, and a tapered portion 523. The first straight portion 521, the tapered portion 523, and the second straight portion 522 are formed sequentially from the upper punch 54 side to the lower punch 55 side. Similarly, the third hole portion 53 has a first straight portion 531, a second straight portion 532, and a tapered portion 533. The first straight portion 531, the tapered portion 533, and the second straight portion 532 are formed sequentially from the upper punch 54 side to the lower punch 55 side. The first straight portions 511, 521, and 531 form the portion on the outer peripheral surface side of the iron chip 1. The second straight portions 512, 522, and 532 form the inner peripheral surface side of the iron chip 1. The tapered portions 513, 523, and 533 form the portion between the outer peripheral surface side and the inner peripheral surface side of the iron chip 1.

[0227] (Upward thrust)

[0228] Upper punch 54 has Figure 12 The first upward-rushing head 541 shown Figure 13 The second upward punch head 542 shown and Figure 14The third upper punch head 543 is shown. The first upper punch head 541 has a first lower end face 541e. The first lower end face 541e forms the outer peripheral surface 12 of the first component 10. The second upper punch head 542 has a second lower end face 542e. The second lower end face 542e forms the outer peripheral surface 22 of the second component 20. The third upper punch head 543 has a third lower end face 543e. The third lower end face 543e forms the outer peripheral surface 32 of the third component 30. The first upper punch head 541, the second upper punch head 542, and the third upper punch head 543 can be formed in a series or independently of each other in a manner that allows them to rise and fall independently. When the first upper punch head 541, the second upper punch head 542, and the third upper punch head 543 are formed in a series, the first lower end face 541e, the second lower end face 542e, and the third lower end face 543e are also formed in a series. The shape of the first lower end face 541e corresponds to the shape of the outer peripheral surface 12 of the first component 10. The shape of the second lower end face 542e corresponds to the shape of the outer peripheral surface 22 of the second component 20. The shape of the third lower end face 543e corresponds to the shape of the outer peripheral surface 32 of the third component 30.

[0229] (Downward punch)

[0230] The lower punch 55 has Figure 12 The first downward punch head 551 shown Figure 13 The second downward punch head 552 shown Figure 14 The third lower punch head 553 is shown. The first lower punch head 551 has a first upper end face 551e. The first upper end face 551e forms the inner peripheral surface 13 of the first component 10. The second lower punch head 552 has a second upper end face 552e. The second upper end face 552e forms the inner peripheral surface 23 of the second component 20. The third lower punch head 553 has a third upper end face 553e. The third upper end face 553e forms the inner peripheral surface 33 of the third component 30. The first lower punch head 551, the second lower punch head 552, and the third lower punch head 553 can be formed in a series or can be formed independently of each other in a manner that allows for independent lifting and lowering. When the first lower punch head 551, the second lower punch head 552, and the third lower punch head 553 are formed in a series, the first upper end face 551e, the second upper end face 552e, and the third upper end face 553e are also formed in a series. The shape of the first upper surface 551e corresponds to the shape of the inner peripheral surface 13 of the first component 10. The shape of the second upper surface 552e corresponds to the shape of the inner peripheral surface 23 of the second component 20. The shape of the third upper surface 553e corresponds to the shape of the inner peripheral surface 33 of the third component 30.

[0231] [Filling Process]

[0232] The cavity formed by the die 50 and the lower punch 55 is filled with raw material powder. The raw material powder can be the aforementioned soft magnetic powder or coated soft magnetic powder. The soft magnetic particles are, for example, spherical. In addition to the soft magnetic powder and coated soft magnetic powder, the raw material powder may also contain a binder and a lubricant. Lubricant can be applied to the inner circumferential surface of the die cavity 50h of the die 50.

[0233] [Molding Process]

[0234] The raw material powder inside the cavity is compressed and formed by the upper punch 54 and the lower punch 55. The direction of compression of the raw material powder is along the radial direction of the stator core 7. The higher the pressure during compression forming, the higher the relative density of the iron chip 1 is produced. Such pressures are, for example, 700 MPa or more, and more specifically, 980 MPa or more.

[0235] [Other processes]

[0236] After the molding process, heat treatment can be performed as needed. For example, heat treatment can remove strain, thereby enabling the manufacture of low-loss iron chip 1. Alternatively, for example, heat treatment can remove binders and lubricants. When the raw material powder contains the aforementioned coated soft magnetic particles 4, the heat treatment temperature is preferably below the decomposition temperature of the insulating coating.

[0237] [Effects]

[0238] The method for manufacturing iron chips according to this method can manufacture the iron chip 1 described above. Specifically, the method for manufacturing iron chips according to this method can manufacture the iron chip 1 described below, which can be easily used to construct an axially spaced rotary motor 9 with excellent magnetic properties. Furthermore, the method for manufacturing iron chips according to this method can integrally form the first component 10, the second component 20, and the third component 30, thus easily improving the productivity of iron chips.

[0239] Implementation Method 2

[0240] [Iron Chip]

[0241] Reference Figure 15 The iron chip 1 according to Embodiment 2 will be described. The main difference between the iron chip 1 of this embodiment and the iron chip 1 according to Embodiment 1 is that it does not have a third component.

[0242] In this manner, without a third component, the first height of the iron chip 1 is the length between the first end face 26 and the end face 16 of the first component 10. The second height is the height of the first component 10, that is, the length between the second end face 27 and the end face 16 of the first component 10.

[0243] The corners between the outer peripheral surface and end face 16 of the first component 10 and the corner 18 between the inner peripheral surface and end face 16 of the first component 10 are preferably chamfered. These chamfers, like the corner 28 described above, can be C-shaped chamfers or R-shaped chamfers. The appropriate range of values ​​for the chamfer length of the corner 18 is the same as the appropriate range of values ​​for the chamfer length of the corner 28.

[0244] In this embodiment, the first component 10 is similar to the first component 10 of the iron chip 1 in Embodiment 1, in that, in the first cross-section, the first average aspect ratio of the soft magnetic particles 40 is 1.2 or higher. The appropriate range of values ​​for the first average aspect ratio is as in Embodiment 1.

[0245] The second component 20 in this embodiment is similar to the second component 20 of the iron chip 1 in Embodiment 1. In the second cross-section, the second average aspect ratio of the soft magnetic particles 40 is 1.2 or higher. The appropriate range of values ​​for the second average aspect ratio is as in Embodiment 1.

[0246] [Effects]

[0247] The iron chip 1 in this method, like the iron chip 1 in Embodiment 1, can easily be used to construct an axially gap-type rotary motor 9 with excellent magnetic properties.

[0248] Implementation Method 3

[0249] [Stator core]

[0250] Reference Figure 16 The stator core 7 according to Embodiment 3 will be described. The stator core 7 of this embodiment has a plurality of iron chips 1 arranged in a ring. Each of the plurality of iron chips 1 in this embodiment is the iron chip 1 according to Embodiment 1. Unlike this embodiment, each of the plurality of iron chips 1 may also be the iron chip 1 according to Embodiment 2. The plurality of iron chips 1 in this embodiment are arranged in a ring such that the steps 240 of the first side surface 24a of the second component 20 of the first iron chip 1 and the steps 240 of the second side surface 24b of the second component 20 of the second iron chip 1 in the circumferentially adjacent iron chips 1 interlock with each other. This stator core 7 in… Figure 18 The axial clearance type rotary motor 9 shown is used in the DS / SR method.

[0251] The variation in length between the first end face and the second end face in the Z-axis direction of each of the multiple iron chips 1 is preferably less than 0.1 mm. The length between the first end face and the second end face in the Z-axis direction is the maximum length between the first end face 26 of the second component 20 and the first end face 36 of the third component 30.

[0252] If the length fluctuation between the first end face 26 of the second component 20 and the first end face 36 of the third component 30 of each of the multiple iron cores 1 is less than 0.1 mm, then the aforementioned length fluctuation is very small. Therefore, the stator core 7 can be used to construct an axially backlash type rotary motor 9 with low noise and vibration. The reason is as follows. The axially backlash type rotary motor 9, as... Figure 18 The stator 8 and rotor 90 are arranged opposite each other. The fluctuation in the length of the stator core 7 is small, thus the fluctuation in the interval between the stator 8 and rotor 90 is small. The small fluctuation in the interval reduces torque pulsation. The small torque pulsation reduces noise and vibration. The fluctuation in length is determined as follows: For each core 1, the length from the first end face 26 of the second component 20 to the first end face 36 of the third component 30 is measured. This length is set as the maximum length of the core 1 along the Z-axis. The difference between the maximum and minimum values ​​of the lengths of each of the multiple cores 1 is calculated. This difference is set as the fluctuation in length. The fluctuation in length between the first end face 26 of the second component 20 and the first end face 36 of the third component 30 of each of the multiple cores 1 is further preferably 0.05 mm or less, and particularly preferably 0.01 mm or less.

[0253] [Effects]

[0254] In this embodiment, the stator core 7 is composed of multiple iron chips 1, each of which allows magnetic flux to pass through easily, as in Embodiment 1. Therefore, it is easy to construct an axially spaced rotary motor 9 with excellent magnetic properties. Furthermore, since the stator core 7 in this embodiment is composed of multiple iron chips 1, as in Embodiment 1, which has excellent production efficiency, production efficiency is also excellent.

[0255] Implementation Method 4

[0256] 〔stator〕

[0257] Reference Figure 17 The stator 8 according to Embodiment 4 will be described. The stator 8 of this embodiment has a stator core 7 and a coil 80. The stator core 7 can be the same as that according to Embodiment 3. The coil 80 is wound around the first part 10 of each lamellar piece 1 of the stator core 7. This stator 8... Figure 18 The axial clearance type rotary motor 9 shown is used in the DS / SR method.

[0258] Each coil 80 has a cylindrical portion formed by winding the coil. The winding uses coated round wire. The coated round wire has a round conductor and an insulating coating provided on the outer periphery of the conductor. Furthermore, in Figure 17 Only the cylindrical portion of each coil 80 is shown in a simplified manner; the two ends of the winding are omitted from the diagram. The stator core 7 can be manufactured by winding the winding around the outside of the first part 10 of each iron chip 1.

[0259] [Effects]

[0260] The stator 8 of this embodiment has the stator core 7 of Embodiment 3, thus it is easy to construct an axially gap type rotary motor 9 with excellent magnetic properties. In addition, the stator 8 of this embodiment has the stator core 7 of Embodiment 3 with excellent productivity, thus resulting in excellent productivity.

[0261] Implementation Method 5

[0262] [Rotating Electric Machine]

[0263] Reference Figure 18 The rotary motor 9 according to Embodiment 5 will be described. Figure 18 This is a cross-sectional view cut through a plane parallel to the rotation axis 91 of the rotary motor 9 and passing through the circumferential center of the iron chip 1. This is referred to in Embodiment 6 described later. Figure 19 Similarly, the rotary motor 9 of this type is an axial clearance type rotary motor. The rotary motor 9 of this type is a DS / SR type having one rotor 90 and two stators 8. That is, the rotor 90 and stators 8 of the rotary motor 9 are arranged axially opposite each other. It is assembled such that one rotor 90 is sandwiched between two stators 8. The stators 8 described in Embodiment 4 above can be used as each stator. The rotary motor 9 can be used as an electric motor or a generator. The rotary motor 9 has a housing 92.

[0264] The housing 92 has a cylindrical internal space for accommodating the stator 8 and rotor 90. The housing 92 has a cylindrical portion 921 and two plates 922. The cylindrical portion 921 surrounds the outer periphery of the stator 8 and rotor 90. Plates 922 are respectively disposed at both ends of the cylindrical portion 921. The two plates 922 are fixed to the end faces of the cylindrical portion 921 in a manner that clamps the stator 8 and rotor 90 from both axial sides. Each plate 922 has a through hole at its center. A bearing 93 is provided in the through hole. A rotating shaft 91 is inserted through the through hole via the bearing 93. The rotating shaft 91 penetrates the housing 92.

[0265] The rotor 90 has magnets 95 and a rotor body. The rotor 90 is a flat plate in this embodiment. The number of magnets 95 can be multiple as in this embodiment, or it can be a single magnet instead. When there are multiple magnets 95, they are arranged at equal intervals circumferentially on the rotor body. Each magnet 95 is a flat plate with a planar shape corresponding to the planar shape of the first end face 36 of the third component 30 of each iron chip 1. Alternatively, each magnet 95 can be a convex lens with a convex surface facing each stator 8. When there is a single magnet 95, it is annular in shape. The single magnet 95 has its S and N poles arranged alternately circumferentially. The rotor body supports the multiple magnets 95. The rotor body is an annular component. The rotor body is rotatably supported by a rotating shaft 91. Each magnet 95 is arranged at equal intervals circumferentially on the rotor body. Each magnet 95 is magnetized axially on the rotating shaft 91. The magnetization directions of the circumferentially adjacent magnets 95 in the rotor body are opposite to each other. Through the rotating magnetic field generated by the stator 8, the magnets 95 are repeatedly attracted and repelled by the iron chips 1, thereby causing the rotor 90 to rotate.

[0266] The stator 8 is configured such that the first end face 36 of the third component 30 of each iron chip 1 faces the magnet 95 of the rotor 90. When the rotor 90 rotates, the first end face 36 of the third component 30 of each iron chip 1 receives magnetic flux from the rotating magnet 95. Figure 3 As shown, if the first end face 36 of the third component 30 of each iron chip 1 is configured as convex as described above, the noise and vibration of the rotary motor 9 can be reduced. The reason is as follows: By configuring the first end face 36 of the third component 30 of each iron chip 1 as convex, it is easier to suppress abrupt changes in the magnetic flux of the magnet 95 of the rotor 90 received by each iron chip 1. Therefore, the cogging torque is easily reduced. With a small cogging torque, noise and vibration are less likely to increase.

[0267] The proportion of the first magnetic reluctance of the iron chip 1 to the total magnetic reluctance of the rotary motor 9 is, for example, 2% or more. As described above, the magnetic reluctance of the first component 10 of the iron chip 1 in Embodiment 1 is less than that of the first component of a conventional iron chip. Therefore, the higher the proportion, the better the magnetic characteristics of the rotary motor 9 having the iron chip 1 compared to a conventional rotary motor having an iron chip. The first magnetic reluctance is the magnetic reluctance of the region in the iron chip 1 excluding the second component 20. That is, the first magnetic reluctance of the iron chip 1 in Embodiment 1 is the sum of the magnetic reluctances of the first component 10 and the third component 30. The first magnetic reluctance of the iron chip 1 in Embodiment 2 is the magnetic reluctance of the first component 10. The proportion is 2% or more, thereby the rotary motor 9 having the iron chip 1 has better magnetic characteristics compared to a conventional rotary motor having an iron chip. The proportion is further 2.5% or more, and particularly 3% or more. The upper limit of the proportion is, for example, 30% in practical applications. That is, the above-mentioned proportions are 2% or more and 30% or less, further examples are 2.5% or more and 28% or less, and specifically examples are 3% or more and 25% or less.

[0268] The magnetic reluctance of the rotary motor 9 is the sum of the second, third, and fourth magnetic reluctances. The second magnetic reluctance is the sum of the magnetic reluctances of the magnets 95 of the rotor 90. The third magnetic reluctance is the sum of the magnetic reluctances of the air gap. The fourth magnetic reluctance is the sum of the magnetic reluctances of the iron chip 1. In the case where the rotary motor 9 has a rear yoke 98 as described in Embodiment 6 below, the magnetic reluctance of the rotary motor 9 is the sum of the second, third, and fourth magnetic reluctances and the magnetic reluctance of the rear yoke 98. Here, each magnetic reluctance is considered as described below.

[0269] The magnetic reluctance of magnet 95 is the product of the area of ​​magnet 95 and the thickness of magnet 95. The area of ​​magnet 95 refers to the area of ​​the surface of magnet 95 opposite to the iron chip 1.

[0270] The magnetic reluctance of each air gap is the product of the area of ​​magnet 95 and the length of the gap. The length of the gap is the axial length between magnet 95 and iron chip 1 along the stator core 7.

[0271] The magnetic reluctance of each iron chip 1 is the sum of the magnetic reluctance of the first component 10, the magnetic reluctance of the second component 20, and the magnetic reluctance of the third component 30. Without the third component 30, the magnetic reluctance of each iron chip 1 is the sum of the magnetic reluctance of the first component 10 and the magnetic reluctance of the second component 20.

[0272] The magnetic reluctance of the first component 10 is the product of the area of ​​the first component 10 and the height of the first component 10. The area of ​​the first component 10 is the area of ​​the cross section of the first component 10 that is orthogonal to the axial direction of the stator core 7.

[0273] The magnetic reluctance of the second component 20 is the product of the area of ​​the second component 20 and the magnetic path length of the second component 20. The area of ​​the second component 20 is the area of ​​the cross-section of the second component 20 orthogonal to the axial direction of the stator core 7. The magnetic path length of the second component 20 is the arc length between the centroids of the circumferentially adjacent first components 10 when viewed from above the stator core 7.

[0274] The magnetic reluctance of the third component 30 is the product of the area of ​​the third component 30 and the magnetic path length of the third component 30. The area of ​​the third component 30 is the area of ​​the cross section of the third component 30 orthogonal to the axial direction of the stator core 7. The magnetic path length of the third component 30 is the arc length between the centroids of the circumferentially adjacent first components 10 when viewed from above the stator core 7.

[0275] The magnetic reluctance of the rear yoke 98 is the product of the area of ​​the rear yoke 98 and the magnetic circuit length of the rear yoke 98. The area of ​​the rear yoke 98 is the area of ​​the cross-section of the rear yoke 98 orthogonal to the axis of the rotating motor 9. The magnetic circuit length of the rear yoke 98 is the arc length between the centers of gravity of the circumferentially adjacent magnets 95 when viewed from above the rotor 90.

[0276] [Effects]

[0277] The rotary motor 9 of this embodiment has the stator 8 of Embodiment 4, thus exhibiting excellent magnetic characteristics. Furthermore, the rotary motor 9 of this embodiment has the stator 8 of Embodiment 4, which also exhibits excellent productivity, thus resulting in excellent productivity.

[0278] Implementation Method 6

[0279] [Rotating Electric Machine]

[0280] Reference Figure 19 The rotary motor 9 according to Embodiment 6 will be described. The rotary motor 9 of this embodiment is an axial clearance type rotary motor. The main difference between the rotary motor 9 of this embodiment and the rotary motor 9 of Embodiment 5 is that it is an SS / DR type having two rotors 90 and one stator 8. That is, the rotary motor 9 has the rotors 90 and the stator 8 arranged axially opposite each other. It is assembled such that one stator 8 is sandwiched between the two rotors 90. The following description focuses on the differences from Embodiment 5. Descriptions of structures identical to those in Embodiment 5 are omitted.

[0281] Each rotor 90 has a rotor body, multiple magnets 95, and a rear yoke 98. The rotor body and multiple magnets 95 are as described in Embodiment 5 above. The rear yoke 98 is disposed between the rotor 90 and the plate 922. The rear yoke 98 is a flat plate-shaped component. The rear yoke 98 is constructed from the same powder-pressed molded body or laminated steel plate as the iron chip 1 described above.

[0282] The stator 8 has a plurality of iron chips 1 arranged in a ring, a coil 80 wound around a first component 10 of each iron chip 1, and a support member for holding the plurality of iron chips 1. (The diagram of the support member is omitted.) The structures of the second component 20 and the third component 30 of each iron chip 1 are identical. That is, the protrusion amount of the first protrusion 211 and the second protrusion 212 of the second component 20 of each iron chip 1 is the same as the protrusion amount of the first protrusion 311 and the second protrusion 312 of the third component 30. Furthermore, the aforementioned steps are not provided on the first side 24a of the first protrusion 211 and the second side 24b of the second protrusion 212 of the second component 20. The coil 80 is as described in Embodiment 4 above. A retainer holds the plurality of iron chips 1 at equal intervals between them. This retainer prevents circumferentially adjacent iron chips 1 from contacting each other.

[0283] [Effects]

[0284] The rotary motor 9 in this embodiment, like the rotary motor 9 in Embodiment 5, has excellent magnetic characteristics. Furthermore, the rotary motor 9 in Embodiment 6, like the rotary motor 9 in Embodiment 5, has a stator 8 with excellent productivity, thus resulting in excellent productivity.

[0285] The invention is not limited to these examples, but is shown in the claims, which include all modifications equivalent to and within the scope of the claims. For example, a rotating electric motor may also have a rotor and a stator.

[0286] Explanation of the label

[0287] 1. Iron chip

[0288] 10 First Component

[0289] 11. Peripheral surface, 12. Outer peripheral surface, 13. Inner peripheral surface

[0290] 14a First side view, 14b Second side view

[0291] 141 First parallel plane, 142 Second parallel plane, 143 First inclined plane

[0292] 16 end faces, 18 corners

[0293] 20 Second Component

[0294] 21 Protrusion, 211 First protrusion, 212 Second protrusion

[0295] 22 Outer peripheral surface, 23 Inner peripheral surface, 24a First lateral surface, 24b Second lateral surface

[0296] 240 steps

[0297] 241 First parallel plane, 242 Second parallel plane, 243 First inclined plane

[0298] 244 The protruding part

[0299] 26 First end face, 27 Second end face, 28 Corner

[0300] 30 Third Component

[0301] 31 Protrusion, 311 First protrusion, 312 Second protrusion

[0302] 32 Outer circumferential surface, 33 Inner circumferential surface

[0303] 34a First side view, 34b Second side view

[0304] 341 First parallel plane, 342 Second parallel plane, 343 First inclined plane

[0305] 36 First end face, 37 Second end face, 38 Corner

[0306] 4. Coated with soft magnetic particles, 40. Soft magnetic particles, 41. Insulating coating

[0307] 5. Mold

[0308] 50 punch die, 50h die cavity

[0309] 51 First Hole

[0310] 511 First straight section, 512 Second straight section, 513 Conical section

[0311] 52 Second Hole

[0312] 521 First straight section, 522 Second straight section, 523 Conical section

[0313] 53 Third hole

[0314] 531 First straight section, 532 Second straight section, 533 Conical section

[0315] 54 Upper punch

[0316] 541 First upward punch head, 541e First lower end face

[0317] 542 Second upper punch head, 542e Second lower end face

[0318] 543 Third upward punch head, 543e Third downward end face

[0319] 55 Downward punch

[0320] 551 First lower punch head, 551e First upper end face

[0321] 552 Second lower punch head, 552e Second upper end face

[0322] 553 Third downward punch head, 553e Third upper end face

[0323] 7 stator core, 8 stator, 80 coils

[0324] 9 Rotary motor

[0325] 90 Rotor, 91 Rotating shaft, 92 Housing

[0326] 921 Cylindrical section, 922 Plate

[0327] 93 bearings, 95 magnets, 98 rear yokes

[0328] E11, E12, E21, E22, E31, E32 Extended surfaces

[0329] Va, Vb are hypothetical surfaces, V21 is the first hypothetical surface, and V22 is the second hypothetical surface.

[0330] θ11, θ21, θ31 First tilt angle

[0331] θ12, θ22, θ32 Second tilt angle

[0332] H1 is the first altitude, H10 is the second altitude.

Claims

1. A stator core of a rotary electric motor configured in an annular shape to form an axially spaced type. This iron chip has the following characteristics: A columnar first component extending axially into the stator core; and A plate-shaped second component is disposed on the first end side of the stator core of the first component in the axial direction. The first component and the second component are integrally formed from a powder pressing molded body. The pressed powder molded body has multiple soft magnetic particles. The soft magnetic particles are flat in shape. In a first cross-section along the axial and radial directions of the stator core of the first component, the first average aspect ratio of the soft magnetic particles is 1.2 or greater. In a second cross-section of the second component orthogonal to the axial direction of the stator core, the second average aspect ratio of the soft magnetic particles is 1.2 or greater. The first average aspect ratio is the ratio of the average length L11 to the average length L12 of the first cross-section, L12 / L11. The second average aspect ratio is the ratio of the average length L21 to the average length L22 of the second cross-section, L22 / L21. The average length L11 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L12 is the average length of the soft magnetic particles along the axial direction of the stator core. The average length L21 is the average length of the soft magnetic particles along the radial direction of the stator core. The average length L22 is the average length of the soft magnetic particles along the circumference of the stator core.

2. The iron chip according to claim 1, wherein, The relative density of the pressed powder molded body is above 85%.

3. The iron chip according to claim 1 or 2, wherein, The soft magnetic particles are composed of pure iron or iron-based alloys. The iron-based alloy is an Fe-Si alloy, an Fe-Al alloy, or an Fe-Si-Al alloy.

4. The iron chip according to claim 1 or 2, wherein, The average particle size of the soft magnetic particles is greater than 30 μm.

5. The iron chip according to claim 1 or 2, wherein, The second height accounts for more than 80% of the first height of the iron chip. The first height is the length of the iron chip along the axial direction of the stator core. The second height is the length along the axial direction of the stator core of the region of the iron chip excluding the second component.

6. The iron chip according to claim 1 or 2, wherein, The second component has: The outer peripheral surface is disposed on the outer peripheral side of the stator core; Inner peripheral surface, which is disposed on the inner peripheral side of the stator core; and The first end face is disposed on the first end side of the stator core in the axial direction. The corners between the outer peripheral surface and the first end face, and the corners between the inner peripheral surface and the first end face, are chamfered. The chamfer length of the corner is 0.1mm or more and 0.5mm or less.

7. A stator core, which is an axially spaced type stator core for a rotating electric motor. It has multiple iron chips configured in a ring shape. Each of the plurality of iron chips is an iron chip as described in any one of claims 1 to 6.

8. A stator, which is an axial clearance type stator for a rotary electric machine. have: The stator core as described in claim 7; and Coils, which are disposed in each of the first components of the stator core.

9. A rotary electric motor, which is a rotary electric motor with axial clearance between the rotor and the stator, The stator is the stator described in claim 8.

10. The rotary electric motor according to claim 9, wherein, The first magnetic reluctance of the iron chip accounts for more than 2% of the total magnetic reluctance of the rotating motor. The first magnetoresistive field is the magnetoresistive field of the iron chip other than the second component.

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