Magnet arrangement method and method for manufacturing a rotor

Abstract

The present disclosure achieves a magnet arrangement method capable of arranging magnetized magnets to be subjected to Halbach arrangement at a predetermined position with high precision. The magnet arrangement method of one embodiment is a method of arranging a plurality of magnetized magnets to be subjected to Halbach arrangement, in which the magnet arrangement method includes an arrangement step of arranging the plurality of magnetized magnets (1) in an arrangement jig (2) composed of a magnetic material, and in the arrangement step, the arrangement jig (2) is caused to have a contact area with a magnetized magnet different from a contact area with another magnetized magnet.

Description

Technical Field

[0001] This disclosure relates to methods for arranging magnets and methods for manufacturing rotors, for example to a method for arranging a plurality of magnetized magnets to be in a Halbach arrangement and a method for manufacturing a rotor having the plurality of magnetized magnets. Background Technology

[0002] In recent years, rotors with magnets arranged in a Halebeck pattern have been put into practical use. Such rotors are manufactured, for example, as disclosed in Patent Document 1, by winding a magnet unit, which is obtained by arranging multiple magnets in a Halebeck pattern on a plate made of a strip of iron and fixing it with epoxy resin, around a rotor core; or as disclosed in Patent Document 2, by using the concave and convex shapes of the rear yoke to arrange the main pole permanent magnet and the auxiliary pole permanent magnet in a Halebeck pattern.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2018-107929

[0006] Patent Document 2: Japanese Patent Application Publication No. 2007-110822 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] The applicant has discovered the following problem: The magnets used for the Helbeck arrangement need to be pre-magnetized, making it difficult to arrange the magnets in the specified positions with high precision.

[0009] This disclosure was made in view of the following problem points, and this disclosure realizes a magnet arrangement method and a rotor manufacturing method that can arrange magnetized magnets to be arranged in a specified position with high precision.

[0010] Solution for solving the problem

[0011] One method of magnet arrangement disclosed herein is a method for arranging multiple magnetized magnets to be arranged in a Hellbeck arrangement, wherein...

[0012] The method includes an arrangement step of arranging the plurality of magnetized magnets in an arrangement fixture made of magnetic materials.

[0013] In the arrangement process, the contact area between the arrangement fixture and the pre-set magnet is different from the contact area between the arrangement fixture and other magnets.

[0014] In the above-described magnet arrangement method, it is preferable that a recess is formed on the contact surface of the arrangement fixture with the magnetized magnet.

[0015] In the above-described magnet arrangement method, it is preferable that a recess is formed on the contact surface between the magnetized magnet and the arrangement fixture.

[0016] In the above-described magnet arrangement method, it is preferable to arrange the different magnetic poles across the groove that serves as the recess.

[0017] In the above-described magnet arrangement method, it is preferable to reduce the difference between the attraction force of one magnetized magnet on the arrangement fixture and the attraction force of the other magnetized magnet on the arrangement fixture when the plurality of magnetized magnets are arranged, so that the contact area between the one magnetized magnet and the arrangement fixture is smaller than the contact area between the other magnetized magnet and the arrangement fixture.

[0018] One embodiment of the present disclosure describes a method for manufacturing a rotor that includes the aforementioned magnet arrangement method.

[0019] Invention Effects

[0020] According to this disclosure, a magnet arrangement method and a rotor manufacturing method are available, which can precisely arrange magnetized magnets to be arranged in a specified position. Attached Figure Description

[0021] Figure 1 This diagram illustrates a scenario in which multiple magnetized magnets are arranged on the Z-axis+ side of the arrangement fixture in the magnet arrangement method of the embodiment.

[0022] Figure 2 It means Figure 1 An enlarged view of Part II.

[0023] Figure 3 This is an enlarged sectional view showing multiple magnetized magnets arranged on the Z-axis+ side of the arrangement fixture.

[0024] Figure 4 This is a diagram used to illustrate magnetic flux loops.

[0025] Figure 5 It is a three-dimensional diagram showing a arrangement of multiple magnetized magnets on the outer periphery of an arrangement fixture.

[0026] Figure 6 This is a diagram showing the manufactured external rotor.

[0027] Figure 7 This is a cross-sectional view showing a magnetized magnet with a concave portion. Detailed Implementation

[0028] Hereinafter, specific embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the following embodiments. Furthermore, for the sake of clarity, the following description and drawings have been appropriately simplified.

[0029] First, the magnet arrangement method of this embodiment will be described. It should be noted that, for clarity, a three-dimensional (XYZ) coordinate system will be used in the following description. The magnet arrangement method of this embodiment is preferably used when arranging magnetized magnets in a Halebeck configuration.

[0030] Figure 1 This diagram illustrates the arrangement of multiple magnetized magnets on the Z-axis+ side of the arrangement fixture in the magnet arrangement method of this embodiment. Figure 2 It means Figure 1 An enlarged view of Part II. Figure 3 This is an enlarged sectional view showing multiple magnetized magnets arranged on the Z-axis+ side of the arrangement fixture.

[0031] In this embodiment, for example, such as Figures 1 to 3 As shown, the magnetized magnets 1 (Helbeck) are arranged on the Z-axis+ side of the arrangement fixture 2. The magnetized magnets 1 are, for example, a quadrangular prism that is long in the X-axis direction, and have N-pole and S-pole portions arranged in a manner that generates a specified magnetic flux. However, the magnetized magnets 1 are not limited to quadrangular prisms; they can also be cylindrical or other polygonal prisms, and the shape of the magnetized magnets 1 is not limited.

[0032] The arrangement clamp 2 is made of a magnetic body, for example, such as Figures 1 to 3 As shown, the basic form is a plate. Here, the arrangement fixture 2 used in this embodiment was conceived to solve the following problems when arranging the magnetized magnets 1.

[0033] Figure 4 This is a diagram used to illustrate a magnetic flux loop. For example, as shown... Figure 4 As shown, the three magnetized magnets 1 are arranged in such a way that they are used as a group of magnets 11 to form a magnetic flux loop R.

[0034] That is, a set of magnets 11 includes a first magnetized magnet 1a arranged on the Y-axis - side, a second magnetized magnet 1b arranged on the Y-axis + side, and a third magnetized magnet 1c arranged in the center as three magnetized magnets 1. Then, it is set that a fourth magnetized magnet 1d is arranged between adjacent magnets 11 as a magnetized magnet 1 for reducing the magnetic flux between adjacent magnets 11.

[0035] In the case where, for example, the magnetized magnets 1 are arranged such that they face the Y-axis+ side, on the flat surface of the magnetic body 100 on the Z-axis+ side, as follows: Figure 4 As shown, in the magnetic flux circuit R formed by a group of magnets 11, the magnetic flux on the side of the second magnetized magnet 1b is greater than the magnetic flux on the side of the first magnetized magnet 1a.

[0036] Therefore, the attraction force A2 of the second magnetized magnet 1b to the magnetic body 100 is greater than the attraction force A1 of the first magnetized magnet 1a to the magnetic body 100. Compared with the arrangement of the first magnetized magnets 1a, it is difficult to control the position of the second magnetized magnet 1b when arranging it. In addition, when arranging the second magnetized magnet 1b, the Z-axis side of the second magnetized magnet 1b may rub strongly against the flat surface of the Z-axis+ side of the magnetic body 100, which may damage the Z-axis side of the second magnetized magnet 1b.

[0037] Furthermore, when arranging the magnetized magnets 1, magnetic flux is generated between different magnetic poles when the adjacent magnetic poles in the Y-axis direction are different. Therefore, the newly arranged magnetized magnet 1 on the Y-axis+ side will be affected by the magnetized magnet 1 adjacent on the Y-axis- side, making it difficult to control the position of the newly arranged magnetized magnet 1 on the Y-axis+ side.

[0038] Furthermore, when arranging the magnetized magnets 1, if the opposing portions of adjacent magnetized magnets 1 in the Y-axis direction have different magnetic poles, the adjacent magnetized magnets 1 will generate an attractive force to each other; or if the opposing portions of adjacent magnetized magnets 1 have the same magnetic pole, the adjacent magnetized magnets 1 will generate a repulsive force to each other. Therefore, it is difficult to control the position of the magnetized magnets 1.

[0039] Therefore, in order to eliminate these problems, such as Figures 1 to 3 As shown, in this embodiment, the arranging fixture 2 has a recess 21 formed on the surface of the arranging fixture 2 for the magnetized magnets 1, i.e., the Z-axis + side. In this embodiment, the recess 21 includes a first recess 21a and a second recess 21b.

[0040] The first recess 21a is formed in the arrangement fixture 2 at the position where the second magnetized magnet 1b is arranged. For example, as Figures 1 to 3 As shown, when viewed from the Z-axis direction, the first recess 21a is a shallow, roughly circular recess, and is arranged in an S-shape with open intervals in the X-axis direction.

[0041] However, the first recesses 21a can also be arranged in a straight line with open intervals in the X-axis direction, or randomly arranged in the X-axis direction. Furthermore, the first recesses 21a are not limited to being generally circular shallow recesses; they can also be polygonal or elliptical shallow recesses, or even grooves.

[0042] In summary, the first recess 21a can be shaped and arranged such that the attraction force of the second magnetized magnet 1b on the arrangement clamp 2 is reduced relative to the attraction force of the second magnetized magnet 1b on the magnetic body 100. In this case, it is preferable that the contact area between the second magnetized magnet 1b and the arrangement clamp 2 is smaller than the contact area between the first magnetized magnet 1a and the arrangement clamp 2, in a way that reduces the difference between the attraction force of the second magnetized magnet 1b on the arrangement clamp 2 and the attraction force of the first magnetized magnet 1a on the arrangement clamp 2.

[0043] The second recess 21b is formed at a position where the adjacent magnetic pole crosses the second recess 21b when the magnetized magnets 1 are arranged in the arranging fixture 2. In this case, it is preferable that the second recess 21b is arranged not only at the boundary between the N pole and S pole portions of the magnetized magnets 1, but also at the boundary of the adjacent magnetized magnets 1 in the Y-axis direction. It should be noted that... Figure 1 The arrangement of the second recess 21b shown is an example, and can be appropriately modified according to the arrangement of the N pole portion and the S pole portion of the magnetized magnet 1.

[0044] The second recess 21b is a groove extending along the X-axis direction and has a length greater than the length of the magnetized magnet 1 in the X-axis direction. This reduces the magnetic flux generated between different magnetic poles. In this case, the width in the Y-axis direction and the depth in the Z-axis direction of the second recess 21b are set such that, when the magnetized magnets 1 are arranged in the arranging fixture 2, the attraction force of the magnetized magnets 1 on the arranging fixture 2 is greater than the attraction or repulsion force between adjacent magnetized magnets 1.

[0045] When the following process is repeated, the magnetized magnet 1 can be arranged in a Heilbeck pattern: using the first recess 21a and the second recess 21b of the arrangement fixture 2 as markers, the magnetized magnets 1a, 1c, 1b, and 1d are arranged on the Z-axis+ side of the arrangement fixture 2 in the order of first magnetized magnet 1a → third magnetized magnet 1c → second magnetized magnet 1b → fourth magnetized magnet 1d, facing the Y-axis+ side.

[0046] At this time, the contact area between the second magnetized magnet 1b and the arrangement clamp 2 is different from the contact area between the first magnetized magnet 1a and the arrangement clamp 2. Then, the first recess 21a is formed such that the attraction force of the second magnetized magnet 1b on the arrangement clamp 2 is reduced relative to the attraction force of the second magnetized magnet 1b on the magnetic body 100.

[0047] Therefore, when arranging the second magnetized magnet 1b, it is easy to control the position of the second magnetized magnet 1b. Furthermore, since the first recess 21a is shallowly concave and its shape differs from that of the second recess 21b, it is easy to visually confirm the position of the second magnetized magnet 1b.

[0048] Here, by reducing the difference between the attraction force of the second magnetized magnet 1b on the arrangement clamp 2 and the attraction force of the first magnetized magnet 1a on the arrangement clamp 2, and making the contact area between the second magnetized magnet 1b and the arrangement clamp 2 smaller than the contact area between the first magnetized magnet 1a and the arrangement clamp 2, the attraction forces of all magnetized magnets 1a, 1b, 1c, and 1d on the arrangement clamp 2 can be approximately averaged. Therefore, the position control of each magnetized magnet 1 can be stabilized.

[0049] Furthermore, when the magnetizing magnets 1 are arranged in the arrangement fixture 2, the second recess 21b is positioned at the boundary of different magnetic poles, thus reducing the magnetic flux generated between the different magnetic poles. Therefore, it is easy to control the position of the newly arranged magnetizing magnets 1 on the Y-axis + side.

[0050] Furthermore, the second recess 21b is formed such that when the magnetized magnets 1 are arranged in the arrangement fixture 2, the attraction force of the magnetized magnets 1 on the arrangement fixture 2 is greater than the attraction or repulsion force between adjacent magnetized magnets 1. Therefore, the magnetized magnets 1 can be newly arranged on the Y-axis + side in a manner that overcomes the attraction or repulsion force between adjacent magnetized magnets 1.

[0051] Through the above, the magnet arrangement method of this embodiment can arrange the magnetized magnets 1 in a predetermined position with high precision. Furthermore, it can reduce the attraction force of the second magnetized magnet 1b on the arrangement fixture 2, thereby suppressing strong friction between the Z-axis side surface of the second magnetized magnet 1b and the arrangement fixture 2, and suppressing damage to the Z-axis side surface of the second magnetized magnet 1b.

[0052] At this time, the second recess 21b is formed on the arranging fixture 2 in such a way that it is arranged on the boundary portion of the adjacent magnetized magnet 1. Therefore, when arranging the magnetized magnet 1, it is only necessary to arrange the magnetized magnet 1 by marking the second recess 21b. Thus, the magnetized magnet 1 can be easily arranged in the specified position.

[0053] Next, the manufacturing method of the rotor will be explained. Figure 5 It is a three-dimensional diagram showing a arrangement of multiple magnetized magnets on the outer periphery of an arrangement fixture. Figure 6 This is a diagram showing the manufactured outer rotor. It should be noted that... Figure 5 In this simplified representation, the recess 21 formed on the outer peripheral surface of the arranging fixture 2 is omitted. For example, when... Figure 5 When the arrangement fixture 2 is made into a cylindrical shape and the magnetized magnets 1 are arranged on the outer peripheral surface of the arrangement fixture 2 so that the magnetized magnets 1 are joined together, the magnetized magnets 1 can be arranged into a cylindrical shape.

[0054] Then, when Figure 6As shown, for example, when the cylindrical magnets 1 are inserted into the interior of the cylindrical rotor core 3 so that the inner circumferential surface of the rotor core 3 is joined with the outer circumferential surface of the magnets 1, and a rotating shaft (not shown) is assembled, an outer rotor 4 can be manufactured. However, the cylindrical magnets 1 can also be fixed to the outer circumferential surface of the rotor core to manufacture an inner rotor.

[0055] This disclosure is not limited to the above-described embodiments, and appropriate modifications may be made without departing from the spirit of the invention.

[0056] For example, in the above embodiment, a magnetic flux loop R is formed by three magnetized magnets 1, but the number of magnetized magnets 1 used to form the magnetic flux loop R, the arrangement of the magnetic poles, etc. are not limited.

[0057] For example, in the above embodiment, a recess 21 is formed in the arranging clamp 2, but it can also be as follows: Figure 7 As shown, a recess 1e is formed in the magnetized magnet 1. In summary, as long as a recess is formed in at least one of the magnetized magnet 1 or the arrangement fixture 2, the attraction force of the magnetized magnet 1 forming a magnetic flux loop can be reduced or the magnetic flux generated between adjacent different magnetic poles can be reduced.

[0058] This application claims priority based on Japanese Application Special Hobby 2021-44582, filed on March 18, 2021, all of which are hereby incorporated.

[0059] Explanation of reference numerals in the attached figures

[0060] 1: Magnetized magnet; 1a: First magnetized magnet; 1b: Second magnetized magnet; 1c: Third magnetized magnet; 1d: Fourth magnetized magnet; 1e: Recess;

[0061] 2: Arrangement fixture;

[0062] 3: Rotor core;

[0063] 4: External rotor;

[0064] 11: Magnet assembly;

[0065] 21: concave part; 21a: first concave part; 21b: second concave part;

[0066] 100: Magnetic body;

[0067] A1, A2: Adsorption force;

[0068] R: Magnetic flux loop.

Claims

1. A method for arranging magnets, comprising arranging multiple magnetized magnets to be arranged in a Hellbeck arrangement, wherein, The magnet arranging method includes an arranging step of arranging the plurality of magnetized magnets in an arranging fixture made of magnetic materials. In the arrangement process, the plurality of magnetized magnets are arranged such that three magnetized magnets are grouped into one magnet group, and a fourth magnetized magnet is placed between adjacent magnet groups. The set of magnets forms a magnetic flux loop. The set of magnets includes a first magnetized magnet disposed on one side, a second magnetized magnet disposed on the other side, and a third magnetized magnet disposed centrally between the first and second magnetized magnets. In the magnetic flux loop formed by the set of magnets, the magnetic flux on the side of the second magnetized magnet is greater than the magnetic flux on the side of the first magnetized magnet. In the arrangement process, the contact area between the arrangement fixture and the second magnetized magnet is made smaller than the contact area between the arrangement fixture and the first magnetized magnet. A first recess and a second recess are formed on the surface of the arranging fixture for arranging the plurality of magnetized magnets. The first recess is formed in the arrangement fixture at the position where the second magnetized magnet is arranged. The second recess is formed at the position where adjacent magnetic poles cross over the second recess when the plurality of magnetized magnets are arranged in the arrangement fixture.

2. The magnet arrangement method according to claim 1, wherein, A recess is formed on the contact surface between the magnetized magnet and the arrangement clamp.

3. A method for manufacturing a rotor, comprising the magnet arrangement method as described in claim 1 or 2.

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