Rotor, motor, blower, refrigeration system, and method for manufacturing a rotor

Abstract

When creating bonded magnets with high magnetic force, there is room for consideration regarding the bonded magnet materials that make up the bonded magnets. [Solution] The rotor (40) of the motor (20) is equipped with a cylindrical bonded magnet (50) containing magnetic powder. The bonded magnet (50) has a first magnet part (51) made of a first bonded magnet material and a second magnet part (52) made of a second bonded magnet material. The second bonded magnet material has a higher melt flow rate than the first bonded magnet material.

Description

Technical Field

[0001] The present disclosure relates to a rotor, a motor, a blower, a refrigeration device, and a method for manufacturing a rotor.

Background Art

[0002] Patent Document 1 discloses an anisotropic bonded magnet. In Patent Document 1, the temperature of the bonded magnet is increased by a heater to improve fluidity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to improve the performance of a motor, the production of a bonded magnet with high magnetic force is required. When producing a bonded magnet with high magnetic force, there is room for consideration in the bonded magnet material that constitutes the bonded magnet.

Means for Solving the Problems

[0005] The rotor of the motor according to the first aspect for solving the above problems includes a cylindrical bonded magnet containing magnetic powder. The bonded magnet has a first magnet portion formed of a first bonded magnet material and a second magnet portion formed of a second bonded magnet material. The second bonded magnet material has a higher melt flow rate than the first bonded magnet material.

[0006] According to the above configuration, the second magnet portion is formed of a bonded magnet material having a different melt flow rate from the first magnet portion. Therefore, it is possible to provide a bonded magnet having a different magnetization direction and magnetic flux magnitude from a bonded magnet having the same shape formed of one type of bonded magnet material for the entire bonded magnet.

[0007] In the rotor of the second viewpoint, the magnetic particle density of the second bonded magnet material is smaller than that of the first bonded magnet material.

[0008] With the above configuration, since the magnetic particle density of the second bonded magnet material is lower than that of the first bonded magnet material, the melt flow rate of the second bonded magnet material can be made higher than that of the first bonded magnet material.

[0009] The rotor in the third aspect is the rotor in the first or second aspect, wherein the bonded magnet is an anisotropic magnet having two or more adjacent magnetic poles in the circumferential direction of the bonded magnet, and the first magnet portion includes the central part of the magnetic pole.

[0010] According to the above configuration, the first magnet portion can be placed at the center of the magnetic pole of the bonded magnet.

[0011] The rotor in the fourth aspect is the rotor in the third aspect, wherein the bonded magnet includes the radial outer surface and inner surface of the bonded magnet, the magnetic pole is provided on the inner surface of the bonded magnet, the second magnetic portion is arranged on the outer surface of the bonded magnet, and the first magnetic portion is arranged on the inner surface of the bonded magnet.

[0012] According to the above configuration, the outer surface of the bonded magnet can be formed by the second magnetic portion.

[0013] The rotor in the fifth aspect is the rotor in the third aspect, wherein the bonded magnet includes the radial outer surface and inner surface of the bonded magnet, the magnetic pole is provided on the outer surface of the bonded magnet, the first magnetic portion is arranged on the outer surface of the bonded magnet, and the second magnetic portion is arranged on the inner surface of the bonded magnet.

[0014] According to the above configuration, the outer surface of the bonded magnet can be formed by the first magnetic portion.

[0015] The rotor of the sixth aspect is such that, in the rotor of the fourth or fifth aspect, the bonded magnet has a first end and a second end opposite to the first end in the axial direction of the bonded magnet, the second magnet portion is positioned at the first end or the second end of the bonded magnet in the axial direction, and the first magnet portion is positioned alongside the second magnet portion in the axial direction.

[0016] According to the above configuration, the second magnet portion can be placed at the first or second end in the axial direction of the bonded magnet.

[0017] The rotor of the seventh aspect is the rotor of the third aspect, wherein the bonded magnet has a third end in the axial direction of the bonded magnet and a fourth end opposite to the third end, the magnetic pole is provided at the third end, the first magnetic portion is located at the third end of the bonded magnet in the axial direction, and the second magnetic portion is located at the fourth end of the bonded magnet in the axial direction.

[0018] According to the above configuration, the first magnet portion can be placed at the third end in the axial direction of the bonded magnet, and the second magnet portion can be placed at the fourth end.

[0019] The rotor of the eighth aspect is the rotor of the seventh aspect, wherein the bonded magnet includes the radial outer surface and the inner surface of the bonded magnet, the magnetic pole is provided on one end face of the bonded magnet in the axial direction, the second magnetic portion is arranged on the outer surface of the bonded magnet, and the first magnetic portion is arranged on the inner surface of the bonded magnet.

[0020] According to the above configuration, the outer surface of the bonded magnet can be formed by the second magnetic portion.

[0021] The motor of the ninth perspective that solves the above problem comprises a rotor and a stator as described in any one of the first to eighth perspectives.

[0022] According to the above configuration, the motor's performance can be improved by using a rotor with a strong magnetic field.

[0023] The blower according to the tenth aspect for solving the above problems includes the motor according to the ninth aspect and a fan unit driven by the motor.

[0024] According to the above configuration, the blower can suitably blow air by the motor with improved performance.

[0025] The refrigeration apparatus according to the eleventh aspect for solving the above problems includes the motor according to the ninth aspect.

[0026] According to the above configuration, the refrigeration apparatus can improve the energy utilization efficiency by the motor with improved performance.

[0027] The method for manufacturing a rotor of a motor according to the twelfth aspect for solving the above problems includes, in a molding die having a die body having a cylindrical cavity, a first injection step of injecting a first bonded magnet material into a first region of the cavity, and a second injection step of injecting a second bonded magnet material into a second region of the cavity different from the first region, wherein the second bonded magnet material has a higher melt flow rate than the first bonded magnet material.

[0028] According to the above configuration, in the second region, since the second magnet portion is formed by a bonded magnet material having a different melt flow rate from the first magnet portion, it is possible to provide a bonded magnet having a different magnetization direction and magnetic flux magnitude from a bonded magnet having the same shape formed by one type of bonded magnet material for the entire bonded magnet.

[0029] The method for manufacturing a rotor according to the thirteenth aspect is the manufacturing method according to the twelfth aspect, wherein the molding die includes a magnetic field generating portion that generates a magnetic field in the cavity, the magnetic field generating portion has magnetic poles arranged side by side in the circumferential direction of the cavity, and the distance from the center of the magnetic pole to the second region is longer than the distance from the center of the magnetic pole to the first region.

[0030] With the above configuration, the magnetic powder of the bonded magnet material injected into the second region, which is away from the magnetic field generating section, can be easily oriented along the magnetic field of the magnetic field generating section. [Brief explanation of the drawing]

[0031] [Figure 1] This is a schematic diagram of the indoor unit for the refrigeration system of the embodiment. [Figure 2] Figure 1 is a cross-sectional view showing the motor and fan of the indoor unit for a refrigeration system. [Figure 3] This is a cross-sectional view of the mold body for manufacturing the bonded magnets that are installed on the rotor of the motor shown in Figure 2. [Figure 4] This is a cross-sectional view of the mold body along the line D4-D4 in Figure 3. [Figure 5] This is a cross-sectional view of the first movable part for manufacturing the bonded magnets that are provided on the rotor of the motor shown in Figure 2. [Figure 6] This is a cross-sectional view of the second movable part for manufacturing the bonded magnets provided on the rotor of the motor shown in Figure 2. [Figure 7] This is a cross-sectional view showing the first movable part movement process in which the first movable part of Figure 5 is moved toward the mold body. [Figure 8] Figure 5 is a cross-sectional view showing the first injection process in which the first bonded magnet material is injected into the cavity by the first movable part. [Figure 9] This is a cross-sectional view showing the second movable part movement process in which the second movable part of Figure 6 is moved toward the mold body. [Figure 10] Figure 6 is a cross-sectional view showing the second injection process in which the second bonded magnet material is injected into the cavity by the second movable part. [Figure 11] Figure 2 is a cross-sectional view of the bonded magnet. [Figure 12] This is a cross-sectional view of a bonded magnet along the line D12-D12 in Figure 11. [Figure 13] This is a cross-sectional view of a bonded magnet provided on the rotor of a modified motor. [Figure 14] This is a cross-sectional view of a bonded magnet along the line D14-D14 in Figure 13. [Figure 15]This is a cross-sectional view of a bonded magnet provided on the rotor of a modified motor. [Figure 16] This is a cross-sectional view of a bonded magnet provided on the rotor of a modified motor. [Figure 17] This is a cross-sectional view of a bonded magnet provided on the rotor of a modified motor. [Modes for carrying out the invention]

[0032] <Embodiment> Referring to Figures 1 to 12, the manufacturing methods for the rotor 40 of the motor 20, the motor 20, the blower 10, the refrigeration device, and the bonded magnet 50 of the embodiment will be described.

[0033] The refrigeration system includes a motor 20. Examples of refrigeration systems include an air conditioner, a water heater, a chiller unit, and a cooling device for cooling the air inside the storage area. The air conditioner is either a dedicated refrigeration unit, a dedicated heating unit, or a heating and cooling unit that can switch between cooling and heating. The air inside the storage area is the air inside refrigerators, freezers, display cases, and containers. In this embodiment, the refrigeration system will be described as an air conditioner.

[0034] Figure 1 shows the indoor unit 1 of an air conditioner. In this embodiment, the motor 20 is provided in the indoor unit 1. The indoor unit 1 is, for example, a wall-mounted type that is attached to the wall of a room. The indoor unit 1 is connected to the outdoor unit of the air conditioner by refrigerant piping.

[0035] The indoor unit 1 includes a heat exchanger that exchanges heat with the air drawn in from the intake port, a blower 10, and a casing 2 that supports the heat exchanger and the blower 10. The heat exchanger and the blower 10 are arranged in the internal space of the casing 2.

[0036] The blower 10 comprises a motor 20 and a fan unit 11 driven by the motor 20. The fan unit 11 is located downstream of the heat exchanger in the airflow path from the intake port to the outlet port of the indoor unit 1. The fan unit 11 is a propeller fan, a centrifugal fan, or a cross-flow fan. Examples of centrifugal fans include turbo fans and sirocco fans. In this embodiment, the fan unit 11 is a cross-flow fan.

[0037] <motor> As shown in Figure 2, the motor 20 is, for example, an outer rotor type motor. The motor 20 comprises a rotor 40 and a stator 30.

[0038] The stator 30 comprises a stator body 31, a stator core 32, and a coil 33. These components constituting the stator 30 are integrally molded using resin molding. The stator body 31 is positioned radially inward of the rotor 40.

[0039] The stator core 32 is formed by laminating conductive steel plates. The steel plates are soft magnetic materials. The stator core 32 has multiple teeth. The coil 33 is formed by winding wire around the teeth of the stator core 32. The winding wire is copper wire or aluminum wire. The winding wire is covered with an insulating material such as enamel resin.

[0040] An insulator is provided between the stator core 32 and the coil 33. The insulator is made of an insulating resin material. The insulator insulates the stator core 32 and the coil 33 so that the current flowing through the coil 33 is not transmitted to the stator core 32.

[0041] The stator 30 further comprises a cylindrical stator outer periphery 34 and a connecting portion 35 that connects the stator body 31 and the stator outer periphery 34. The stator outer periphery 34 is provided on the radially outer side of the stator body 31. The connecting portion 35 connects the stator body 31 and the stator outer periphery 34. A housing chamber 36 is formed between the stator body 31 and the stator outer periphery 34. The housing chamber 36 is configured in an annular shape when viewed from the axial direction AD of the bonded magnet 50.

[0042] The motor 20 further comprises a rotating shaft 21. The rotating shaft 21 rotates integrally with the bonded magnet 50. The stator 30 has a through hole 37 in which the rotating shaft 21 is positioned. At least one bearing 22 is positioned in the through hole 37. The bearing 22 supports the rotating shaft 21 so that it rotates relative to the stator 30. A rotor 40 is attached to one end of the rotating shaft 21. In this embodiment, the rotating shaft 21 is supported by two bearings 22 so as to be rotatable relative to the stator 30.

[0043] The rotor 40 includes a cylindrical bonded magnet 50 containing magnetic powder. At least a portion of the bonded magnet 50 is placed in the housing chamber 36. The bonded magnet 50 is positioned radially outward of the stator body 31. The bonded magnet 50 is positioned radially inward of the outer circumference 34 of the stator.

[0044] The rotor 40 further comprises a cover member 41. The bonded magnet 50 is formed separately from the cover member 41 and is attached to the cover member 41 so as to rotate integrally with the cover member 41. The cover member 41 is provided at one end of the bonded magnet 50 in the axial direction AD of the bonded magnet 50. The bonded magnet 50 is attached to the cover member 41, for example, by mounting claws. The bonded magnet 50 may also be attached to the cover member 41 by adhesive or the like.

[0045] The cover member 41 is formed from a resin material. Preferably, the resin material forming the cover member 41 is the same as the resin material used for the binder in the bonded magnet 50. However, the resin material forming the cover member 41 may be different from the resin material used for the binder in the bonded magnet 50.

[0046] The cover member 41 has an axial cover portion 41A and a radial cover portion 41B extending from the axial cover portion 41A in the axial direction AD. The axial cover portion 41A is connected to one end of the bonded magnet 50 in the axial direction AD. The radial cover portion 41B covers at least partially the radially outer side of the bonded magnet 50 and the stator 30.

[0047] <Bonded Magnets> The bonded magnet 50 will be described with reference to Figures 11 and 12. The bonded magnet 50 is an anisotropic magnet having two or more adjacent magnetic poles in the circumferential direction of the bonded magnet 50. The bonded magnet 50 includes an outer circumferential surface 50A and an inner circumferential surface 50B in the radial direction of the bonded magnet 50. The magnetic poles are provided on either the outer circumferential surface 50A or the inner circumferential surface 50B in the radial direction of the bonded magnet 50. In this embodiment, the magnetic poles are provided on the inner circumferential surface 50B of the bonded magnet 50. The bonded magnet 50 is formed from a bonded magnet material. The bonded magnet material includes magnetic powder and a binder.

[0048] Magnetic powder has an easy magnetization axis. The length of the magnetic powder in a second direction perpendicular to the easy magnetization axis is longer than the length in a first direction along the easy magnetization axis. The magnetic powder has a flattened shape. The magnetic powder is in the form of fine powder or granules. The magnetic powder is either ferrite magnetic powder or rare-earth magnetic powder. Rare-earth magnetic powders include NdFeB-based magnetic powder or SmCo-based magnetic powder.

[0049] Binders such as nylon resin and PPS (Polyphenylene Sulfide) resin are used. Examples of nylon resins include nylon 12, nylon 6, nylon 6,6, nylon 11, nylon 6,12, nylon 6,10, nylon 6,66, and nylon MXD6. Various types of nylon resins may be used individually or in mixtures of multiple types.

[0050] The bonded magnet 50 has a first magnetic portion 51 and a second magnetic portion 52. The first magnetic portion 51 includes the central part of the magnetic pole of the bonded magnet 50. The first magnetic portion 51 is located on the outer circumferential surface 50A or the inner circumferential surface 50B of the bonded magnet 50. In this embodiment, the first magnetic portion 51 is located on the inner circumferential surface 50B of the bonded magnet 50. The second magnetic portion 52 is located on the outer circumferential surface 50A or the inner circumferential surface 50B of the bonded magnet 50. In this embodiment, the second magnetic portion 52 is located on the outer circumferential surface 50A of the bonded magnet 50.

[0051] The bonded magnet material includes a first magnet material and a second magnet material. The first magnet portion 51 is made of the first bonded magnet material. The second magnet portion 52 is made of the second bonded magnet material. The magnetic powder filling rate of the first bonded magnet material and the second magnet material is 80 wt% or more and less than 100 wt%. Preferably, the magnetic powder filling rate of the first bonded magnet material and the second magnet material is 88 wt% or more and 95 wt% or less.

[0052] The first bonded magnet material has a different melt flow rate from the second bonded magnet material. In this embodiment, the second bonded magnet material has a higher melt flow rate than the first bonded magnet material. The melt flow rate is an indicator of the fluidity of the bonded magnet material. A higher melt flow rate indicates higher fluidity of the bonded magnet material. A lower melt flow rate indicates lower fluidity of the bonded magnet material.

[0053] The binder used for the second bonded magnet material is the same material as the binder used for the first bonded magnet material. The magnetic particle density of the second bonded magnet material is lower than that of the first bonded magnet material. Because the binder type of the second bonded magnet material is the same as that of the first bonded magnet material, and the magnetic particle density is lower than that of the first bonded magnet material, the melt flow rate of the second bonded magnet material is higher than that of the first bonded magnet material. The magnetic particle density can be confirmed, for example, by observing the surface of the bonded magnet 50 using a scanning electron microscope (SEM).

[0054] In this embodiment, orientation means that the easy magnetization axis of the magnetic powder contained in the bonded magnet material is aligned in a predetermined direction. The orientation ratio is defined by the following equation (1) as the average value of the orientation component of each magnetic powder with respect to the predetermined direction.

number

[0055] X is the orientation factor. N is the total number of magnetic particles contained in any given region. θ is the angle between a given direction and the easy magnetization axis of each magnetic particle. Any given region is defined, for example, by the observation range of a scanning electron microscope.

[0056] The magnetic powder of the bonded magnet 50 is oriented by the magnetic field generating unit 65, which will be described later. In this embodiment, a second magnetic unit 52 with a higher melt flow rate than the first magnetic unit 51 is arranged in the portion of the bonded magnet 50 that is farther from the magnetic field generating unit 65. Therefore, the orientation rate of the portion of the bonded magnet 50 that is farther from the magnetic field generating unit 65 can be improved.

[0057] <Method for manufacturing bonded magnets> The manufacturing method of the bonded magnet 50 will be described with reference to Figures 3 to 10.

[0058] The bonded magnet 50 is formed by a mold 60. The mold 60 comprises a mold body 61. The mold body 61 is made of a non-magnetic material. The non-magnetic material is, for example, non-magnetic stainless steel. The mold body 61 has a cylindrical cavity 62. In plan view, the cavity 62 is annular. Bonded magnet material is injected into the cavity 62 from an injection port. The injection port is provided on the end face 62A of the cavity 62 in the direction CD in the cylindrical axis direction. The end face 62A of the cavity 62 in the direction CD in the cylindrical axis direction is annular. The injection port is provided on the mold body 61 so as to correspond to the center of the magnetic pole of the magnetic field generating unit 65, which will be described later.

[0059] As shown in Figures 3 and 4, the cavity 62 has a first region 63 and a second region 64 in a cross section perpendicular to the cylindrical axis CD of the cavity 62. The dashed lines in Figures 3 and 4 are imaginary lines to distinguish the first region 63 and the second region 64. The second region 64 is a region different from the first region 63 in the radial direction of the cavity 62. In the radial direction of the cavity 62, the length of the first region 63 is longer than the length of the second region 64. The first region 63 is adjacent to the second region 64 in the radial direction.

[0060] The mold 60 includes a magnetic field generating unit 65 that generates a magnetic field within the cavity 62. The magnetic field generating unit 65 has magnetic poles arranged in a circumferential direction. On the outer circumference of the magnetic field generating unit 65, the south poles and north poles are arranged alternately in the circumferential direction. The number of magnetic poles of the bonded magnet 50 corresponds to the number of magnetic poles of the magnetic field generating unit 65. In this embodiment, the number of magnetic poles of the magnetic field generating unit 65 is 10. The number of magnetic poles of the magnetic field generating unit 65 is not limited to 10. The magnetic field generating unit 65 may have as many as 2 or more even natural number magnetic poles.

[0061] The cavity 62 has an outward surface 62B and an inward surface 62C in the radial direction of the cavity 62. The magnetic field generating unit 65 is positioned on either the outward surface 62B side or the inward surface 62C side of the cavity 62 in the radial direction. In this embodiment, the magnetic field generating unit 65 is positioned on the inward surface 62C side of the cavity 62.

[0062] The first region 63 faces the center of the magnetic pole of the magnetic field generating unit 65 in the radial direction of the cavity 62. The distance from the magnetic field generating unit 65 to the second region 64 is longer than the distance from the magnetic field generating unit 65 to the first region 63. The distance from the center of the magnetic pole of the magnetic field generating unit 65 to the second region 64 is longer than the distance from the center of the magnetic pole of the magnetic field generating unit 65 to the first region 63. In this embodiment, the distance from the center of the magnetic pole of the magnetic field generating unit 65 to the inner surface 64A of the second region 64 is longer than or equal to the distance from the center of the magnetic pole of the magnetic field generating unit 65 to the outer surface 63A of the first region 63. The magnetic field generating unit 65 is adjacent to the first region 63 in the radial direction of the cavity 62.

[0063] The mold 60 includes a movable part 66 configured to move relative to the mold body 61. The movable part 66 has an injection port 66A and a runner 66B. Bonded magnet material is injected into the injection port 66A. The runner 66B is arranged in the movable part 66, for example, so as to spread radially. The movable part 66 is configured to move relative to the mold body 61 so that the runner 66B is positioned to correspond to the injection port of the cavity 62. The bonded magnet material injected from the injection port 66A is injected into the cavity 62 through the runner 66B and the injection port.

[0064] As shown in Figures 5 and 6, the movable part 66 includes a first movable part 67 for injecting the first bonded magnet material into a first region 63 of the cavity 62, and a second movable part 68 for injecting the second bonded magnet material into a second region 64 of the cavity 62. By swapping the first movable part 67 and the second movable part 68 and injecting each bonded magnet material into the cavity 62, a bonded magnet 50 is formed.

[0065] The first movable part 67 has a first movable part body 67A and a region partition 67B. The region partition 67B is provided on the lower end surface 67C of the first movable part body 67A. The region partition 67B may be detachably attached to the first movable part body 67A. In plan view, the region partition 67B is annular. The region partition 67B is formed of, for example, a soft magnetic material.

[0066] The region partition 67B is provided on the first movable part body 67A so as to correspond to the first region 63 or the second region 64 of the cavity 62. In this embodiment, the region partition 67B is provided on the first movable part body 67A so as to correspond to the second region 64 of the cavity 62. The runner 66B of the first movable part 67 is provided on the first movable part 67 so as to correspond to the first region 63. The runner 66B of the second movable part 68 is provided on the second movable part 68 so as to correspond to the second region 64.

[0067] The manufacturing process for the bonded magnet 50 will be described with reference to Figures 7 to 10. The manufacturing process for the bonded magnet 50 includes a first movable part movement step. In the first movable part movement step, the first movable part 67 is moved toward the mold body 61, thereby closing the molding die 60.

[0068] The manufacturing method for the bonded magnet 50 includes a first injection step of injecting a first bonded magnet material into a first region 63 of the cavity 62. The first injection step is a step for injection molding the first magnet portion 51 of the bonded magnet 50. In the first injection step, when the first bonded magnet material is injected from the injection port 66A of the first movable portion 67, it is injected from the injection port through the runner 66B into the first region 63 of the cavity 62. In the first injection step, the first bonded magnet material flows in a direction toward downward from the injection port and in a direction spreading in the circumferential direction, so that the first region 63 of the cavity 62 is filled with the first bonded magnet material.

[0069] The manufacturing method for the bonded magnet 50 includes a first separation step in which the first movable part 67 is moved away from the mold body 61. The first separation step is performed after the completion of the first injection step and after the first bonded magnet material has hardened. The first separation step separates the first bonded magnet material injected into the first region 63 of the cavity 62 from the first bonded magnet material in the runner 66B.

[0070] The manufacturing method for the bonded magnet 50 includes a second movable part movement step. In the second movable part movement step, the second movable part 68 is moved toward the mold body 61, thereby closing the molding die 60.

[0071] The manufacturing method for the bonded magnet 50 includes a second injection step of injecting a second bonded magnet material into a second region 64 of the cavity 62. The second injection step is a step for injection molding the second magnet portion 52 of the bonded magnet 50. In the second injection step, when the second bonded magnet material is injected from the injection port 66A of the second movable portion 68, it is injected from the injection port through the runner 66B into the second region 64 of the cavity 62. In the second injection step, the second bonded magnet material flows in a direction toward downward from the injection port and in a direction spreading in the circumferential direction, so that the second region 64 of the cavity 62 is filled with the second bonded magnet material.

[0072] The manufacturing method for the bonded magnet 50 includes a second separation step in which the second movable part 68 is moved away from the mold body 61. The second separation step is performed after the completion of the second injection step and after the second bonded magnet material has hardened. The second separation step separates the second bonded magnet material injected into the second region 64 of the cavity 62 from the second bonded magnet material in the runner 66B.

[0073] The method for manufacturing the bonded magnet 50 further comprises an extraction step in which the bonded magnet 50 is removed from the cavity 62. The extraction step is performed after the second bonded magnet material has hardened in the second injection step. The method for manufacturing the bonded magnet 50 further comprises a magnetization step in which the bonded magnet 50 is magnetized. The magnetization step is performed after the second injection step. Preferably, the magnetization step is performed after the extraction step.

[0074] In this embodiment, the first movable part movement step, the first injection step, and the first detachment step are performed before the second movable part movement step, the second injection step, and the second detachment step. Therefore, the magnetic powder of the first bonded magnet material injected into the first region 63 by the magnetic field generating unit 65 can be suitably oriented.

[0075] <Operation of the Embodiment> The operation of this embodiment will now be explained. In this embodiment, since the entire bonded magnet 50 is composed of two different types of bonded magnet materials, it is possible to provide a bonded magnet 50 that has a different magnetization direction and magnetic flux magnitude compared to a bonded magnet of the same shape composed of only one type of bonded magnet material.

[0076] In this embodiment, the first magnetic portion 51, which is provided at the center of the magnetic pole of the bonded magnet 50, is made of a different material from the second magnetic portion 52, which includes the radial outer surface 50A of the bonded magnet 50. This makes it possible to provide a bonded magnet 50 that is made of a single type of bonded magnet material and a bonded magnet 50 with different magnetic flux lines or magnetic flux densities.

[0077] <Effects of the Embodiment> The effects of this embodiment will now be explained. (1) The rotor 40 of the motor 20 is equipped with a cylindrical bonded magnet 50 containing magnetic powder. The bonded magnet 50 has a first magnet portion 51 made of a first bonded magnet material and a second magnet portion 52 made of a second bonded magnet material. The second bonded magnet material has a higher melt flow rate than the first bonded magnet material.

[0078] According to the above configuration, the second magnet section 52 is made of a bonded magnet material with a different melt flow rate than the first magnet section 51. Therefore, it is possible to provide a bonded magnet 50 that has a different magnetization direction and magnetic flux magnitude than a bonded magnet of the same shape in which the entire bonded magnet 50 is made of a single type of bonded magnet material.

[0079] (2) The magnetic particle density of the second bonded magnet material is smaller than that of the first bonded magnet material.

[0080] With the above configuration, since the magnetic particle density of the second bonded magnet material is lower than that of the first bonded magnet material, the melt flow rate of the second bonded magnet material can be made higher than that of the first bonded magnet material.

[0081] (3) The bonded magnet 50 is an anisotropic magnet having two or more adjacent magnetic poles in the circumferential direction of the bonded magnet 50. The first magnetic portion 51 includes the center of the magnetic pole.

[0082] According to the above configuration, the first magnetic portion 51 can be placed at the center of the magnetic pole of the bonded magnet 50.

[0083] (4) The bonded magnet 50 includes an outer circumferential surface 50A and an inner circumferential surface 50B in the radial direction of the bonded magnet 50. The magnetic poles are provided on the inner circumferential surface 50B of the bonded magnet 50. The second magnetic portion 52 is arranged on the outer circumferential surface 50A of the bonded magnet 50. The first magnetic portion 51 is arranged on the inner circumferential surface 50B of the bonded magnet 50.

[0084] According to the above configuration, the outer surface 50A of the bonded magnet 50 can be formed by the second magnetic portion 52.

[0085] (5) The motor 20 comprises a rotor 40 and a stator 30.

[0086] According to the above configuration, the motor 20 can have its performance improved by the rotor 40 with a strong magnetic force.

[0087] (6) The blower 10 comprises a motor 20 and a fan section 11 driven by the motor 20.

[0088] With the above configuration, the blower 10 can effectively blow air using the improved motor 20.

[0089] (7) The refrigeration unit is equipped with a motor 20.

[0090] According to the above configuration, the refrigeration system can improve its energy utilization efficiency with the improved performance of the motor 20.

[0091] (8) A method for manufacturing the rotor 40 of the motor 20 comprises a molding die 60 having a mold body 61 having a cylindrical cavity 62, a first injection step of injecting a first bonded magnet material into a first region 63 of the cavity 62, and a second injection step of injecting a second bonded magnet material into a second region 64 of the cavity 62 that is different from the first region 63. The second bonded magnet material has a higher melt flow rate than the first bonded magnet material.

[0092] According to the above configuration, in the second region 64, the second magnet portion 52 is formed by a bonded magnet material with a different melt flow rate from the first magnet portion 51. Therefore, a bonded magnet 50 can be provided that has a different magnetization direction and magnetic flux magnitude than a bonded magnet of the same shape, in which the entire bonded magnet is made of one type of bonded magnet material.

[0093] (9) The mold 60 includes a magnetic field generating unit 65 that generates a magnetic field within the cavity 62. The magnetic field generating unit 65 has magnetic poles arranged in the circumferential direction of the cavity 62. The distance from the center of the magnetic pole to the second region 64 is longer than the distance from the center of the magnetic pole to the first region 63.

[0094] With the above configuration, the magnetic powder of the bonded magnet material injected into the second region 64, which is away from the magnetic field generating unit 65, can be easily oriented along the magnetic field of the magnetic field generating unit 65.

[0095] <Example of changes> The rotor 40, motor 20, blower 10, refrigeration device, and method for manufacturing the rotor 40 of this disclosure may also be, in addition to the embodiments described above, for example, the modified examples shown below and a combination of at least two mutually non-inconsistent modified examples.

[0096] The motor 20 may be an inner rotor type motor. As shown in Figures 2, 13, and 14, in this modified example, the magnetic poles are provided on the outer circumferential surface 50A of the bonded magnet 50. The first magnetic portion 51 is arranged on the outer circumferential surface 50A of the bonded magnet 50. The first magnetic portion 51 includes the center of the magnetic pole. The second magnetic portion 52 is arranged on the inner circumferential surface 50B of the bonded magnet 50. According to the configuration of this modified example, the outer circumferential surface 50A of the bonded magnet 50 can be formed by the first magnetic portion 51.

[0097] The second magnetic portion 52 of the bonded magnet 50 may be located at the end of the bonded magnet 50 in the axial direction AD. As shown in Figures 2, 15, and 16, the bonded magnet 50 has a first end 50C and a second end 50D opposite to the first end 50C in the axial direction AD. Figure 15 is an example of the bonded magnet 50 of this modification when the motor 20 is an outer rotor type motor. Figure 15 is an example of the bonded magnet 50 of this modification when the motor 20 is an inner rotor type motor. The second magnetic portion 52 is located at the first end 50C or the second end 50D of the bonded magnet 50 in the axial direction AD. In this modification, the second magnetic portion 52 is located at the first end 50C and the second end 50D of the bonded magnet 50 in the axial direction AD. The first magnetic portion 51 is located alongside the second magnetic portion 52 in the axial direction AD. According to the configuration of this modified example, the second magnet portion 52 can be placed at the first end 50C or the second end 50D in the axial direction AD of the bonded magnet 50.

[0098] The motor 20 may be an axial gap type motor. As shown in Figures 2 and 17, the bonded magnet 50 has a third end 50E and a fourth end 50F opposite to the third end 50E in the axial AD of the bonded magnet 50. In this modified example, the magnetic pole is provided at the third end 50E. The third end 50E includes one end face 50G in the axial AD of the bonded magnet 50. The magnetic pole is provided at the end face 50G. The first magnetic portion 51 is located at the third end 50E of the bonded magnet 50 in the axial AD. The second magnetic portion 52 is located at the fourth end 50F of the bonded magnet 50 in the axial AD. The bonded magnet 50 includes an outer circumferential surface 50A and an inner circumferential surface 50B in the radial direction of the bonded magnet 50. The second magnetic portion 52 is located at the outer circumferential surface 50A of the bonded magnet 50. The first magnetic portion 51 is located at the inner circumferential surface 50B of the bonded magnet 50. According to the configuration of this modified example, the first magnet portion 51 can be placed at the third end 50E in the axial direction AD of the bonded magnet 50, and the second magnet portion 52 can be placed at the fourth end 50F. Furthermore, according to the configuration of this modified example, the outer circumferential surface 50A of the bonded magnet 50 can be formed by the second magnet portion 52.

[0099] The binder for the second bonded magnet material may be made of a material with a different melt flow rate than the binder for the first bonded magnet material. In this case, as long as the second bonded magnet material is configured to have a melt flow rate higher than that of the first bonded magnet material, the magnetic particle density of the second bonded magnet material may be the same as or higher than that of the first bonded magnet material.

[0100] The bonded magnet 50 may have at least one magnet section different from the first magnet section 51 and the second magnet section 52. The at least one magnet section includes, for example, a third magnet section. The third magnet section is formed, for example, from a third bonded magnet material having a higher melt flow rate than the first bonded magnet material and the second bonded magnet material. The distance from the third magnet section to the magnetic field generating section 65 is longer than the distance from the second magnet section 52 to the magnetic field generating section 65. The magnetic particle density of the third bonded magnet material is lower than that of the second bonded magnet material. The binders of the first to third bonded magnet materials may be the same or different.

[0101] The bonded magnet 50 may have a shape that follows the flow of the magnetic field of the magnetic field generating unit 65. The bonded magnet 50 may have, for example, a petal-like shape. The bonded magnet 50 may have, for example, a first part including magnetic poles and a second part located midway between adjacent magnetic poles in the circumferential direction. The outer circumferential surface of the first part may be located, for example, radially, further outward than the outer circumferential surface of the second part. The inner circumferential surface of the first part may be located radially further inward than the inner circumferential surface of the second part.

[0102] The bonded magnet 50 may be covered with a resin. The resin covering the bonded magnet 50 may be the same resin material as the binder of the bonded magnet 50, or it may be a different resin material.

[0103] The second movable part movement step, the second injection step, and the second detachment step may be performed before the first movable part movement step, the first injection step, and the first detachment step.

[0104] The magnetization process may be omitted. In this case, for example, the bonded magnet 50 is magnetized by the magnetic field generating unit 65.

[0105] The motor 20 may be used in an outdoor unit for a refrigeration system or in a compressor for a refrigeration system.

[0106] While embodiments of the rotor 40, motor 20, blower 10, refrigeration system, and method for manufacturing the rotor 40 have been described above, it will be understood that various modifications to the form and details are possible without departing from the spirit and scope of the rotor 40, motor 20, blower 10, refrigeration system, and method for manufacturing the rotor 40 as described in the claims. [Explanation of Symbols]

[0107] 10... Blower, 11... Fan section, 20... Motor, 30... Stator, 40... Rotor, 50... Bonded magnet, 50A... Outer surface, 50B... Inner surface, 50C... First end, 50D... Second end, 50E... Third end, 50F... Fourth end, 50G... End face, 51... First magnet section, 52... Second magnet section, 60... Molding die, 61... Mold body, 62... Cavity, 62A... End face, 63... First region, 64... Second region, 65... Magnetic field generating section.

Claims

1. The rotor (40) of the motor (20), The device includes a cylindrical bonded magnet (50) containing magnetic powder, The bonded magnet (50) is A first magnet part (51) made of a first bonded magnet material, It has a second magnetic part (52) made of a second bonded magnetic material, The second bonded magnet material has a higher melt flow rate than the first bonded magnet material. Rotor.

2. The magnetic particle density of the second bonded magnet material is smaller than that of the first bonded magnet material. The rotor according to claim 1.

3. The bonded magnet (50) is a polar anisotropic magnet having two or more adjacent magnetic poles in the circumferential direction of the bonded magnet (50), The first magnet portion (51) includes the central part of the magnetic pole, The rotor according to claim 1.

4. The bonded magnet (50) includes an outer circumferential surface (50A) and an inner circumferential surface (50B) in the radial direction of the bonded magnet (50). The magnetic pole is provided on the inner circumferential surface (50B) of the bonded magnet (50), The second magnetic portion (52) is arranged on the outer circumferential surface (50A) of the bonded magnet (50). The first magnet portion (51) is positioned on the inner circumferential surface (50B) of the bonded magnet (50). The rotor according to claim 3.

5. The bonded magnet (50) includes an outer circumferential surface (50A) and an inner circumferential surface (50B) in the radial direction of the bonded magnet (50). The magnetic pole is provided on the outer circumferential surface (50A) of the bonded magnet (50), The first magnet portion (51) is arranged on the outer circumferential surface (50A) of the bonded magnet (50), The second magnetic portion (52) is positioned on the inner circumferential surface (50B) of the bonded magnet (50). The rotor according to claim 3.

6. The bonded magnet (50) has a first end (50C) in the axial direction (AD) of the bonded magnet (50) and a second end (50D) opposite to the first end (50C), The second magnet portion (52) is positioned in the axial direction (AD) at the first end (50C) or the second end (50D) of the bonded magnet (50), The first magnet portion (51) is arranged in the axial direction (AD) alongside the second magnet portion (52), The rotor according to claim 4 or 5.

7. The bonded magnet (50) has a third end (50E) in the axial direction (AD) of the bonded magnet (50) and a fourth end (50F) opposite to the third end (50E), The magnetic pole is provided at the third end (50E), The first magnet portion (51) is positioned in the axial direction (AD) at the third end (50E) of the bonded magnet (50), The second magnet portion (52) is positioned in the axial direction (AD) at the fourth end (50F) of the bonded magnet (50), The rotor according to claim 3.

8. The bonded magnet (50) includes an outer circumferential surface (50A) and an inner circumferential surface (50B) in the radial direction of the bonded magnet (50). The magnetic pole is provided on one end face (50G) of the bonded magnet (50) in the axial direction (AD), The second magnetic portion (52) is arranged on the outer circumferential surface (50A) of the bonded magnet (50). The first magnet portion (51) is positioned on the inner circumferential surface (50B) of the bonded magnet (50). The rotor according to claim 7.

9. A motor (20), The rotor (40) described in claim 1, A stator (30) and a stator (30) are provided. Motor.

10. A blower (10), The motor (20) described in claim 9, The system comprises a fan section (11) driven by the aforementioned motor, Blower.

11. A refrigeration device, The motor (20) according to claim 9, Refrigeration equipment.

12. A method for manufacturing the rotor (40) of a motor (20), In a mold (60) having a mold body (61) having a cylindrical cavity (62), a first injection step is performed in which a first bonded magnet material is injected into a first region (63) of the cavity (62), The process includes a second injection step of injecting a second bonded magnet material into a second region (64) of the cavity, which is different from the first region (63), The second bonded magnet material has a higher melt flow rate than the first bonded magnet material. A method for manufacturing a rotor.

13. The mold (60) includes a magnetic field generating unit (65) that generates a magnetic field within the cavity (62), The magnetic field generating unit (65) has magnetic poles arranged in the circumferential direction of the cavity (62), The distance from the center of the magnetic pole to the second region (64) is longer than the distance from the center of the magnetic pole to the first region (63). The method for manufacturing a rotor according to claim 12.

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