Method for manufacturing magnets, rotating electric machines, fluid machinery, refrigeration equipment, and magnet manufacturing apparatus.

Abstract

The present invention provides a method for manufacturing magnets that can reduce the amount of hardened areas where the magnetization direction is aligned in areas other than the cavity, as well as a rotating electric machine, a fluid machine, a refrigeration device, and a magnet manufacturing apparatus. [Solution] The method for manufacturing a magnet includes an injection step of injecting a bonded magnet material containing magnetic powder from an injection device (300) into a mold (400). The mold (400) has a cavity (460), a spool (470) into which the bonded magnet (92) material is injected from the injection device (300), and a runner (480) that connects from the spool outlet (472) of the spool (470) to a plurality of gates (490) that open into the cavity (460). The injection step includes a magnetization step of applying a magnetic field to the bonded magnet material upstream of the spool outlet (472) in the flow path of the bonded magnet material, and an orientation step of applying a magnetic field to the bonded magnet material in the cavity (460).

Description

Technical Field

[0001] The present disclosure relates to a method for manufacturing a magnet, a rotating electric machine, a fluid machine, a refrigeration device, and a magnet manufacturing apparatus.

Background Art

[0002] A method for manufacturing a magnet by injection molding is known. Patent Document 1 discloses an injection molding apparatus provided with a magnetic flux applying portion that applies a magnetic field to a bonded magnet material at the gate of a runner connected to a cavity. The magnetic flux applying portion of Patent Document 1 magnetizes the bonded magnet material before it enters the cavity.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the manufacturing method of Patent Document 1, since a magnetic field is applied to the gate of the runner, many magnetized and hardened portions (hereinafter referred to as magnetic pole portions) with aligned magnetization directions occur in portions other than the cavity, especially in the runner.

Means for Solving the Problems

[0005] A first aspect of a method for manufacturing a magnet that solves the problem is a method for manufacturing a magnet, comprising an injection step of injecting a bonded magnet material containing magnetic powder from an injection device into a mold, wherein the mold has a cavity, a spool into which the bonded magnet material is injected from the injection device, and a runner connecting from the spool outlet of the spool to a plurality of gates opening into the cavity, and the injection step comprises a magnetization step of applying a magnetic field to the bonded magnet material upstream of the spool outlet in the flow path of the bonded magnet material, and an orientation step of applying a magnetic field to the bonded magnet material in the cavity.

[0006] In this configuration, the bonded magnet material is magnetized upstream of the spool outlet in the flow path of the bonded magnet material. Because the bonded magnet material is magnetized upstream of the spool outlet, the amount of magnetic pole generated at the runner can be reduced compared to when magnetization occurs at the runner.

[0007] A second aspect of the method for manufacturing a magnet is the method for manufacturing a magnet according to the first aspect, wherein the injection device comprises a cylinder for storing the bonded magnet material and a nozzle for connecting the cylinder to an injection port which is the open end of the spool of the mold, and in the magnetization step, a magnetic field is applied to the bonded magnet material in the cylinder or the nozzle.

[0008] In this configuration, the bonded magnet material is magnetized in the cylinder or nozzle of the injection device. This suppresses the formation of magnetic poles in the mold.

[0009] A third aspect of the method for manufacturing a magnet is the method for manufacturing a magnet according to the first aspect, wherein the spool is provided with an injection port into which the bonded magnet material is injected from the injection device, and in the magnetization step, a magnetic field is applied to the bonded magnet material between the injection port and the spool outlet.

[0010] In this configuration, the bonded magnet material is magnetized upstream of the runner in the mold. Therefore, the amount of magnetic poles generated in the mold can be reduced compared to when magnetization occurs in the runner.

[0011] The fourth aspect of the magnet manufacturing method is a method of manufacturing a magnet according to any one of the first to third aspects, wherein in the magnetization step, a magnetic field is applied to the bonded magnet material by a permanent magnet.

[0012] This configuration allows for reduced power consumption during the magnetization process compared to applying a magnetic field using an electromagnet.

[0013] The fifth aspect of the magnet manufacturing method is a method of manufacturing a magnet according to any one of the first to third aspects, wherein in the magnetization step, a magnetic field is applied to the bonded magnet material by an electromagnet.

[0014] With this configuration, the magnetic field applied to the bonded magnet material during the magnetization process can be switched on and off, and the strength of the magnetic field can be adjusted, using an electromagnet.

[0015] The sixth aspect of the rotating electric machine comprises a stator and a rotor, and at least one of the stator and the rotor is fitted with a magnet manufactured by any one of the magnet manufacturing methods described in the first to fifth aspects.

[0016] With this configuration, the magnets used in at least one of the stator and rotor are manufactured by the magnet manufacturing method described above, resulting in strong magnetic force. Strong magnets can improve the rotational characteristics of a rotating electric machine.

[0017] The fluid machine of the seventh perspective is equipped with a rotating electric machine of the sixth perspective. With this configuration, the performance of the fluid machine can be improved by a rotating electric machine with improved rotational characteristics.

[0018] The refrigeration system of the eighth perspective is equipped with a rotating electric machine of the sixth perspective. With this configuration, the performance of the refrigeration system can be improved by a rotating electric machine with improved rotational characteristics.

[0019] The magnet manufacturing apparatus from the ninth perspective for solving the problem is a magnet manufacturing apparatus, which includes an injection device for injecting a bonded magnet material containing magnetic powder, a mold having a cavity, a sprue into which the bonded magnet material is injected from the injection device, and a runner connecting from the sprue outlet of the sprue to a plurality of gates opening into the cavity, a first magnetic field applying unit for applying a magnetic field upstream of the sprue outlet in the flow path of the bonded magnet material, and a second magnetic field applying unit for applying a magnetic field into the cavity.

[0020] According to this configuration, the bonded magnet material is magnetized upstream of the sprue outlet in the flow path of the bonded magnet material. Since the bonded magnet material is magnetized upstream of the sprue outlet, the magnetic pole portions generated in the runner can be reduced compared to the case of magnetizing in the runner.

Brief Description of the Drawings

[0021] [Figure 1] It is a schematic diagram of a refrigeration device according to the first embodiment. [Figure 2] It is a partial cross-sectional view of a fluid machine according to the first embodiment. [Figure 3] It is a cross-sectional view of a magnet used in the fluid machine of FIG. 2. [Figure 4] It is a schematic diagram of a magnet manufacturing apparatus according to the first embodiment. [Figure 5] It is a schematic diagram showing a method of manufacturing a magnet by the magnet manufacturing apparatus of FIG. 4. [Figure 6] It is a schematic diagram of a magnet manufacturing apparatus according to the second embodiment. [Figure 7] It is a schematic diagram of a magnet manufacturing apparatus according to the third embodiment. [Figure 8] It is a schematic diagram of a magnet manufacturing apparatus according to the first modification. [Figure 9] It is a schematic diagram of a cavity in a magnet manufacturing apparatus according to the second modification. [Figure 10] It is a perspective view of a magnet manufactured by the magnet manufacturing apparatus of FIG. 9.

Modes for Carrying Out the Invention

[0022] <First Embodiment> Referring to Figures 1 to 5, a refrigeration apparatus, a fluid machine, a rotating electric machine, a magnet manufacturing apparatus, and a magnet manufacturing method according to the first embodiment will be described.

[0023] <Refrigeration equipment> As shown in Figure 1, in this embodiment, an air conditioner 10A will be described as an example of a refrigeration system 10. The air conditioner 10A comprises an indoor unit 20 installed inside a room and an outdoor unit 30 installed outside a room. The air conditioner 10A also comprises a fluid machine 40.

[0024] <Fluid machinery> The fluid machine 40 converts mechanical energy into fluid energy. The fluid machine 40 includes a rotating electric machine 50. In this embodiment, a blower 40A is described as an example of the fluid machine 40. The blower 40A is built into another device. For example, the indoor unit 20 of an air conditioner 10A has a blower 40A. The blower 40A sends air to the heat exchanger inside the indoor unit 20. The outdoor unit 30 may also have a blower as the fluid machine 40. The blower 40A includes a rotating electric machine 50 and a fan 60.

[0025] <Rotating Electric Machinery> As shown in Figure 2, the rotating electric machine 50 is, for example, a motor. The rotating electric machine 50 comprises a stator 70 and a rotor 90. At least one of the stator 70 and the rotor 90 is fitted with a magnet 92 manufactured by a magnet manufacturing method described later. In this embodiment, the magnet 92 is used as the core of the rotor 90. In this embodiment, the magnet 92 is used in the outer rotor, but the magnet 92 may also be used in the inner rotor.

[0026] The stator 70 comprises a stator core 71, windings 72, and a mold 73. The stator 70 is formed in a cylindrical shape overall. The stator core 71 is made of laminated electrical steel sheets, for example. The stator core 71 has teeth 74 that extend radially and are arranged in a plurality in the circumferential direction. The windings 72 are wound around the teeth 74. The windings 72 are electrically connected to a power supply (not shown). The mold 73 is made of resin. The mold 73 covers the stator core 71 and the windings 72. When a drive current is supplied to the windings 72, the stator 70 generates a rotating magnetic field on its outer circumference.

[0027] A bearing 75 is fixed to the inner circumference of the stator 70. The bearing 75 is fixed to the inner circumference of the stator 70 by a fixing member 76. The fixing member 76 is fitted onto the inner circumference of the stator 70 while holding the bearing 75 on its inner circumference.

[0028] The rotating shaft 80 of the rotating electric machine 50 is rotatably supported by a bearing 75. The outer surface of the rotating shaft 80 contacts the inner surface of the bearing 75. The rotating shaft 80 is rotatably supported by the bearing 75 with its own axis center as the axis of rotation Z.

[0029] The rotor 90 is an outer rotor. The rotor 90 has a flange 91 fixed to the rotating shaft 80 and a magnet 92. The flange 91 is made of resin. The flange 91 is formed in a disc shape. The flange 91 has a central hole 93 fixed to the outer circumferential surface of the rotating shaft 80. The flange 91 is fixed to a portion of the rotating shaft 80 that protrudes outward from the stator 70 in the axial direction. The magnet 92 is fixed to the flange 91.

[0030] Fan 60 is, for example, a cross-flow fan. Fan 60 is fixed to flange 91. Fan 60 is positioned on the side of flange 91 opposite to the side where stator 70 is located. Fan 60 is formed in an elongated shape along the rotation axis Z.

[0031] Figure 3 is a view of the magnet 92 from a direction parallel to the rotation axis Z. The magnet 92 is formed in a cylindrical shape. The magnet 92 is a ring magnet having multiple magnetic poles arranged in the circumferential direction. In the example in Figure 3, the multiple magnetic poles are provided on the inner circumferential surface of the magnet 92. As shown in Figure 2, the axial end of the magnet 92 is fixed to the outer edge side of the flange 91. The magnet 92 is positioned on the side of the flange 91 where the stator 70 is located. The inner circumferential surface of the magnet 92 faces the outer circumferential surface of the stator 70. The magnet 92 is a bonded magnet. The magnet 92 is manufactured as a molded product 100 by the magnet manufacturing method described later.

[0032] <Magnet manufacturing equipment> As shown in Figure 4, the magnet manufacturing apparatus 200 is an apparatus for manufacturing bonded magnets by injection molding. The material for the bonded magnet is a bonded magnet material in which magnetic powder is mixed with a binder. The magnetic powder is ferrite magnetic powder or rare earth magnetic powder. The rare earth magnetic powder includes NdFeB-based magnetic powder, SmCo-based magnetic powder, or SmFeN-based magnetic powder. The binder can be nylon resin or PPS (Polyphenylene Sulfide) resin, etc. Examples of nylon resins include nylon 12, nylon 6, nylon 6,6, nylon 11, nylon 6,12, nylon 6,10, nylon 6,66, nylon MXD6, etc. Various types of nylon resin may be used individually or in mixtures of multiple types.

[0033] Hereinafter, the magnet manufacturing apparatus 200 will simply be referred to as the manufacturing apparatus 200. The manufacturing apparatus 200 comprises an injection device 300, a molding die 400, a first magnetic field application unit 500, and a second magnetic field application unit 600.

[0034] The injection device 300 injects bonded magnet material containing magnetic powder. The injection device 300 has a cylinder 310 and a nozzle 320. The cylinder 310 stores the bonded magnet material. The nozzle 320 is attached to the tip of the cylinder 310. The nozzle 320 connects the cylinder 310 to the injection port 471, which is the open end of the spool 470 of the mold 400.

[0035] A hopper 330 for storing chip-shaped bonded magnet material is connected to cylinder 310. The chip-shaped bonded magnet material moves from hopper 330 to cylinder 310. A heater (not shown) is provided in cylinder 310. The heat from the heater melts the chip-shaped bonded magnet material in cylinder 310. A screw 340 is provided inside cylinder 310. As the screw 340 rotates, the melted bonded magnet material inside cylinder 310 moves along the groove of the screw 340 to the tip of cylinder 310. The bonded magnet material that has moved to the tip of cylinder 310 by the screw 340 passes through nozzle 320 and is injected into injection port 471.

[0036] The molding die 400 includes a first mounting portion 411, a second mounting portion 412, and a spool bushing 430. The molding die 400 is supported by attaching the first mounting portion 411 and the second mounting portion 412 to a fixing plate or the like. The first mounting portion 411 is provided with a first opening 413 that penetrates the first mounting portion 411 in a first direction D1. The second mounting portion 412 is positioned with a gap between it and the first mounting portion 411 on the first direction D1 side. The spool bushing 430 is positioned in the first opening 413.

[0037] The molding die 400 includes a first movable die 421, a second movable die 422, and a third movable die 423. Each of the first movable die 421, the second movable die 422, and the third movable die 423 is positioned between a first mounting portion 411 and a second mounting portion 412.

[0038] The first movable part 421 is positioned on the first direction D1 side with respect to the first mounting part 411. The first movable part 421 is provided with a second opening 424 that penetrates the first movable part 421 in the first direction D1. The second opening 424 overlaps with the first opening 413 in the first direction D1. A part of the spool bush 430 is positioned in the second opening 424.

[0039] The second movable type 422 is positioned on the first direction D1 side relative to the first movable type 421. The second movable type 422 has a recess 425 on the surface facing the first direction D1. The second movable type 422 has a groove 427 on the surface facing the direction opposite to the first direction D1.

[0040] The third movable type 423 is positioned on the side of the first direction D1 relative to the second movable type 422. The third movable type 423 has a protrusion 426 on the surface opposite to the first direction D1. The protrusion 426 of the third movable type 423 overlaps with the recess 425 of the second movable type 422 in the first direction D1.

[0041] The mold 400 includes a support portion 440 and a drive portion 450. The support portion 440 supports the third movable mold 423 relative to the second mounting portion 412. The support portion 440 includes a fixed portion 441, a movable portion 442, a biasing portion 443, and an ejector pin 444. The fixed portion 441 is fixed to the side of the second mounting portion 412 opposite to the first direction D1. The movable portion 442 is fixed to the side of the third movable mold 423 that is on the side of the first direction D1. The biasing portion 443 biases the movable portion 442 relative to the fixed portion 441 in the direction opposite to the first direction D1. As a result, the third movable mold 423 to which the movable portion 442 is fixed is biased in the direction opposite to the first direction D1, and furthermore, the second movable mold 422 and the first movable mold 421 are also biased in the direction opposite to the first direction D1. The ejector pin 444 is fixed to the fixed part 441. The ejector pin 444 is inserted through a through hole through which the third movable part 423 is inserted in the first direction D1.

[0042] The drive unit 450 moves the first movable type 421, the second movable type 422, and the third movable type 423, respectively, along the first direction D1 relative to the second mounting part 412.

[0043] The mold 400 has a cavity 460, a spool 470, and a runner 480. In this embodiment, the cavity 460 is provided between the second movable mold 422 and the third movable mold 423. Specifically, the cavity 460 is demarcated by the recess 425 of the second movable mold 422, the protrusion 426 of the third movable mold 423, and a portion of the surface of the third movable mold 423 on the side opposite to the first direction D1. The mold 400 is provided with a plurality of cavities 460. The through hole of the third movable mold 423 through which the ejector pin 444 is inserted opens into the cavity 460.

[0044] The spool 470 is located inside the spool bush 430. Bonded magnet material is injected into the spool 470 from the injection device 300. The spool 470 is equipped with an injection port 471. Bonded magnet material is injected into the injection port 471 from the injection device 300. The injection port 471 is exposed in the mold 400 in the direction opposite to the first direction D1. The bonded magnet material injected into the injection port 471 flows out from the spool outlet 472. The bonded magnet material that flows out from the spool outlet 472 flows into the runner 480.

[0045] The runner 480 connects from the spool outlet 472 of the spool 470 to several gates 490. Each of the gates 490 opens into a cavity 460. Each of the gates 490 opens into one of the multiple cavities 460. Several gates 490 open into one of the multiple cavities 460.

[0046] In this embodiment, the runner 480 has a first passage portion 481 and a second passage portion 482. The first passage portion 481 is a portion that extends from the spool outlet 472 in a direction perpendicular to the first direction D1. Multiple first passage portions 481 extend toward each of the multiple cavities 460. Multiple first passage portions 481 extend in a branching manner from the spool 470. The first passage portion 481 is formed when the first movable mold 421 fits over the groove portion 427 of the second movable mold 422. The second passage portion 482 connects from the first passage portion 481 to the cavity 460. The second passage portion 482 extends in the first direction D1. The second passage portion 482 penetrates the second movable mold 422 in the first direction D1.

[0047] The first magnetic field application unit 500 magnetizes the magnetic powder contained in the bonded magnet material. During the manufacture of the bonded magnet, the bonded magnet material flows in the following order: cylinder 310, nozzle 320, spool 470, runner 480, and cavity 460. The first magnetic field application unit 500 applies a magnetic field upstream of the spool outlet 472 in the flow path of the bonded magnet material. For example, the first magnetic field application unit 500 applies a magnetic field to the cylinder 310 or the nozzle 320. In this embodiment, the first magnetic field application unit 500 applies a magnetic field to the nozzle 320.

[0048] In this embodiment, the first magnetic field application unit 500 is provided on the injection device 300. The first magnetic field application unit 500 is positioned so as not to apply a magnetic field around the gate 490. The first magnetic field application unit 500 is positioned so as not to apply a magnetic field to the runner 480. The first magnetic field application unit 500 is positioned away from the second movable mold 422 on which the runner 480 is formed, in the direction opposite to the first direction D1. In this embodiment, the first magnetic field application unit 500 is positioned away from the molding die 400, in the direction opposite to the first direction D1.

[0049] The first magnetic field application unit 500 has a first permanent magnet 510. The first permanent magnet 510 is mounted around the nozzle 320 in the injection device 300. In this embodiment, a plurality of first permanent magnets 510 are arranged to sandwich the nozzle 320. The first permanent magnets 510 generate a magnetic field along a direction perpendicular to the first direction D1, as shown by the white arrows in Figure 4. The magnetic field of the first permanent magnets 510 passes through the nozzle 320.

[0050] The second magnetic field application unit 600 orients the magnetic powder contained in the bonded magnet material. The magnetic powder contained in the bonded magnet material has an easy magnetization axis. 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 predetermined direction is, for example, the direction aligned with the magnetic field applied by the second magnetic field application unit 600. The bonded magnet is formed when the bonded magnet material hardens in the cavity 460 with the magnetic powder oriented.

[0051] The second magnetic field application unit 600 applies a magnetic field to the cavity 460. The second magnetic field application unit 600 is positioned away from the first magnetic field application unit 500 in the first direction D1. In this embodiment, the second magnetic field application unit 600 is located in the third movable type 423. In this embodiment, the second magnetic field application unit 600 is provided within the protrusion 426 of the third movable type 423.

[0052] The second magnetic field application unit 600 is positioned so as not to apply a magnetic field around the gate 490. The second magnetic field application unit 600 is positioned so as not to apply a magnetic field to the runner 480.

[0053] The second magnetic field application unit 600 includes, for example, a second permanent magnet 610. The magnetic field of the second permanent magnet 610 passes through the cavity 460. The arrangement of the second permanent magnet 610 is set according to the magnetic poles of the bonded magnet manufactured by the manufacturing apparatus 200. The second permanent magnet 610 generates a magnetic field along a direction perpendicular to the first direction D1, as shown by the white arrows in Figure 4.

[0054] <How to manufacture magnets> Referring to Figure 5, the method for manufacturing magnets will be explained. The method for manufacturing magnets includes an injection process. In the injection process, bonded magnet material containing magnetic powder is injected from the injection device 300 into the mold 400. In the injection process, the bonded magnet material flows through the flow path to the cavity 460. The cavity 460 is filled with the bonded magnet material.

[0055] The injection process includes a magnetization process and an orientation process. The bonded magnet material undergoes the magnetization process and the orientation process along the flow path.

[0056] The magnetization process is performed on the bonded magnet material flowing upstream of the spool outlet 472. In the magnetization process, a magnetic field is applied to the bonded magnet material upstream of the spool outlet 472 in the flow path of the bonded magnet material. In this embodiment, in the magnetization process, for example, a magnetic field is applied to the bonded magnet material at the nozzle 320. In this embodiment, in the magnetization process, a magnetic field is applied to the bonded magnet material by the first permanent magnet 510 of the first magnetic field application unit 500. As the bonded magnet material passes through the nozzle 320, the magnetic powder contained in the bonded magnet material is magnetized through the magnetization process.

[0057] The orientation process is performed on the bonded magnet material that has flowed into the cavity 460. In the orientation process, a magnetic field is applied to the bonded magnet material in the cavity 460. In this embodiment, in the orientation process, a magnetic field is applied to the bonded magnet material by the second permanent magnet 610 of the second magnetic field application unit 600. When a magnetic field is applied, the magnetic powder contained in the bonded magnet material in the cavity 460 is oriented. As the bonded magnet material with oriented magnetic powder hardens, a molded product 100 is formed in the cavity 460. In the magnet 92 as the molded product 100 shown in Figure 3, the second magnetic field application unit 600 aligns the magnetic powder so that its easy magnetization axis is aligned in the direction shown by the dashed line from one magnetic pole to the adjacent magnetic pole.

[0058] The method for manufacturing the magnet includes an extraction step. In the extraction step, the molded product 100 is removed from the cavity 460 of the mold 400. As the third movable mold 423 moves in a first direction D1 relative to the second movable mold 422, the tip of the ejector pin 444 protrudes from the through hole of the third movable mold 423, and the ejector pin 444 pulls the molded product 100 away from the protrusion 426 of the third movable mold 423. Subsequently, the molded product 100 is pulled away from the recess 425 of the second movable mold 422.

[0059] The method for manufacturing magnets includes a removal step. In the removal step, the hardened portion of the bonded magnet material outside the cavity 460 (hereinafter referred to as the hardened portion 110) is removed from the mold 400. The hardened portion 110 occurs in the flow path of the bonded magnet material other than the cavity 460. Specifically, the hardened portion 110 occurs in the spool 470 and the runner 480. As the second movable mold 422 moves in a first direction D1 relative to the first movable mold 421, the groove 427 that forms the first passage portion 481 of the runner 480 is exposed. In this state, the hardened portion 110 of the first passage portion 481 is removed. Since the hardened portion 110 of the second passage portion 482 and the hardened portion 110 of the spool 470 are connected to the hardened portion 110 of the first passage portion 481, the entire hardened portion 110 is removed from the mold 400.

[0060] <Operation of the Embodiment> The first operation of this embodiment will now be described. In the case of polar anisotropic magnets with complex orientation directions or thick magnets, the orientation may be uneven because a sufficient magnetic field cannot be obtained from the second magnetic field application unit 600 for orientation. For example, if the second magnetic field application unit 600 is placed on the protrusion 426 of the third movable mold 423, as in the manufacturing apparatus 200, there is a limitation in increasing the size of the second permanent magnet 610 of the second magnetic field application unit 600, making it difficult to increase the magnetic field applied to the cavity 460. In contrast, if the bonded magnet material is not yet in the cavity 460, the area where the magnetic field is applied by the first magnetic field application unit 500 can be smaller, making it possible to apply a higher magnetic field to the bonded magnet material. As a result, the bonded magnet material is magnetized with a high magnetic field before it enters the cavity 460, making it easier for the magnetic powder to orient within the cavity 460, and improving the orientation rate of the molded product 100 compared to when no magnetic field is applied to the bonded magnet material before it enters the cavity 460. The orientation ratio is defined by the following equation (1) as the average value of the orientation components of each magnetic particle in a given direction.

[0061]

number

[0062] In equation (1), X is the orientation factor. In equation (1), N is the total number of magnetic particles contained in any given region. In equation (1), 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 (SEM).

[0063] As described above, applying a magnetic field to the bonded magnet material at the gate 490 just before it enters the cavity 460 allows the bonded magnet material to enter the cavity 460 in a magnetized state, which is expected to improve the orientation of the molded product 100. However, if a magnetic field application section is provided on the runner 480, the magnetic field continues to be applied to the bonded magnet material even when the flow of the bonded magnet material has stopped. In this case, there is a risk that a hardened portion (hereinafter referred to as the magnetic pole portion) will be formed at the gate 490 of the runner 480, where the easy magnetization axis of the magnetic powder is aligned in the direction of the hardened portion 110. The magnetic pole portion is not suitable for recycling because it has a magnetic pole.

[0064] The hardened portion 110, which is the part other than the molded product 100, is recycled. Specifically, the hardened portion 110 is crushed into chips and reused as bond magnet material. If the hardened portion 110 contains magnetic poles, these magnetic poles may be attracted to the blades of the crusher or solidify in the hopper 330, causing blockages. Therefore, if magnetic poles are present in the hardened portion 110, demagnetization is necessary for recycling. However, because the runner 480 is widely spread in the mold 400, the hardened portion 110 becomes large, requiring a large demagnetizing coil to demagnetize the hardened portion 110. This increases the cost of the demagnetizing power supply and power consumption, thus increasing the cost required for demagnetization. It is also conceivable to cut off the first passage portion 481 and the second passage portion 482 of the runner 480 and use a small demagnetizing coil, but in this case, multiple demagnetization steps would be required, resulting in increased demagnetization costs due to the increased labor.

[0065] In the magnet manufacturing method of this embodiment, a magnetic field is applied upstream of the spool outlet 472 in the flow path of the bonded magnet material, so no magnetic pole portion is formed in the runner 480. This reduces the demagnetization cost mentioned above.

[0066] The second operation of this embodiment will now be described. In the manufacturing method of the molded product 100 of this embodiment, a magnetic field is applied to the bonded magnet material by the nozzle 320 of the injection device 300 during the magnetization process. Since no magnetic pole portion is formed in the mold 400, demagnetization is unnecessary when recycling the hardened portion 110.

[0067] The third function of this embodiment will now be described. In the manufacturing apparatus 200, multiple cavities 460 are provided in the mold 400. The manufacturing apparatus 200 is a multi-cavity system in which multiple molded products 100 are manufactured in a single injection molding cycle. In the case of multi-cavity molding, many hardened portions 110 are generated due to the many branches of the runner 480. By using the magnet manufacturing method of this embodiment in the case of multi-cavity molding, the amount of magnetic pole portion can be reduced even if there are many hardened portions 110.

[0068] <Effects of the Embodiment> The effects of this embodiment will now be explained. (1-1) A method for manufacturing a magnet includes an injection step of injecting a bonded magnet material containing magnetic powder from an injection device 300 into a mold 400. The mold 400 has a cavity 460, a spool 470 into which the bonded magnet material is injected from the injection device 300, and a runner 480 that connects from a spool outlet 472 of the spool 470 to a plurality of gates 490 that open into the cavity 460. The injection step includes a magnetization step of applying a magnetic field to the bonded magnet material upstream of the spool outlet 472 in the flow path of the bonded magnet material, and an orientation step of applying a magnetic field to the bonded magnet material in the cavity 460.

[0069] In this configuration, the bonded magnet material is magnetized upstream of the spool outlet 472 in the flow path of the bonded magnet material. Because the bonded magnet material is magnetized upstream of the spool outlet 472, the amount of magnetic pole generated at the runner 480 can be reduced compared to when magnetization occurs at the runner 480.

[0070] (1-2) The injection device 300 includes a cylinder 310 for storing bonded magnet material and a nozzle 320 that connects the cylinder 310 to an injection port 471 which is the open end of the spool 470 of the mold 400. In the magnetization process, a magnetic field is applied to the bonded magnet material at the nozzle 320.

[0071] With this configuration, the bonded magnet material is magnetized in the nozzle 320 of the injection device 300. This suppresses the formation of magnetic poles in the mold 400.

[0072] (1-3) In the magnetization process, a magnetic field is applied to the bonded magnet material by the first permanent magnet 510. With this configuration, the power consumption required to apply the magnetic field in the magnetization process can be reduced compared to when the magnetic field is applied by an electromagnet.

[0073] (1-4) The rotating electric machine 50 comprises a stator 70 and a rotor 90. A magnet 92 manufactured by a magnet manufacturing method is used in at least one of the stator 70 and the rotor 90.

[0074] In this configuration, the magnet 92 used in at least one of the stator 70 and rotor 90 is manufactured by the magnet manufacturing method, and therefore the magnetic force of the magnet 92 is strong. The rotational characteristics of the rotating electric machine 50 can be improved by the strong magnetic force of the magnet 92.

[0075] (1-5) The fluid machine 40 is equipped with a rotating electric machine 50. With this configuration, the performance of the fluid machine 40 can be improved by the rotating electric machine 50, which has improved rotational characteristics.

[0076] (1-6) The magnet manufacturing apparatus 200 comprises an injection device 300, a mold 400, a first magnetic field application unit 500, and a second magnetic field application unit 600. The injection device 300 injects bonded magnet material containing magnetic powder. The mold 400 has a cavity 460, a spool 470 into which the bonded magnet material is injected from the injection device 300, and a runner 480 that connects from the spool outlet 472 of the spool 470 to a plurality of gates 490 that open into the cavity 460. The first magnetic field application unit 500 applies a magnetic field upstream of the spool outlet 472 in the flow path of the bonded magnet material. The second magnetic field application unit 600 applies a magnetic field into the cavity 460.

[0077] In this configuration, the bonded magnet material is magnetized upstream of the spool outlet 472 in the flow path of the bonded magnet material. Because the bonded magnet material is magnetized upstream of the spool outlet 472, the amount of magnetic pole generated at the runner 480 can be reduced compared to when magnetization occurs at the runner 480.

[0078] <Second Embodiment> Referring to Figure 6, a refrigeration apparatus, fluid machinery, rotating electric machine, magnet manufacturing apparatus, and magnet manufacturing method according to the second embodiment will be described. Components in this embodiment that are common to the first embodiment are denoted by the same reference numerals as in the first embodiment, and redundant descriptions are omitted.

[0079] The manufacturing apparatus 200 of this embodiment differs from the manufacturing apparatus 200 of the first embodiment in the arrangement of the first magnetic field application unit 500. The first magnetic field application unit 500 of this embodiment is provided in the molding die 400. The first magnetic field application unit 500 is positioned, for example, in a direction perpendicular to the first direction D1, where it overlaps with the spool 470. The first magnetic field application unit 500 of this embodiment applies a magnetic field to the molding die 400. The first permanent magnet 510 is provided, for example, in the first movable die 421. The magnetic field of the first permanent magnet 510 passes through the spool 470.

[0080] In this embodiment, the magnetization process is performed on the bonded magnet material flowing through the spool 470. During the magnetization process, a magnetic field is applied to the bonded magnet material between the injection port 471 and the spool outlet 472.

[0081] <Operation of the Embodiment> The first operation of this embodiment will now be described. In this embodiment, the first magnetic field application unit 500 applies a magnetic field to the spool 470, creating magnetic pole portions within the spool 470. Since the number of spools 470 is less than the number of runners 480, even if magnetic pole portions are created, demagnetization can be performed with a small demagnetizing coil. Furthermore, the number of demagnetization cycles is reduced. The number of runners 480 is, for example, the number of first passage sections 481 and second passage sections 482.

[0082] The second operation of this embodiment will now be described. In this embodiment, the molding die 400 is provided with a first magnetic field application unit 500. Modifying the molding die 400 is relatively easy compared to modifying the injection unit 300. For this reason, it is easy to provide the first magnetic field application unit 500 in the manufacturing apparatus 200.

[0083] <Effects of the Embodiment> The effects of this embodiment will now be explained. (2-1) The spool 470 is equipped with an injection port 471 into which bonded magnet material is injected from the injection device 300. In the magnetization process, a magnetic field is applied to the bonded magnet material between the injection port 471 and the spool outlet 472.

[0084] In this configuration, the bonded magnet material is magnetized upstream of the runner 480 in the mold 400. Therefore, the amount of magnetic pole generated in the mold 400 can be reduced compared to when magnetization occurs in the runner 480.

[0085] <Third Embodiment> Referring to Figure 7, a refrigeration apparatus, fluid machinery, rotating electric machine, magnet manufacturing apparatus, and magnet manufacturing method according to the third embodiment will be described. Components in this embodiment that are common with the first embodiment are denoted by the same reference numerals as in the first embodiment, and redundant descriptions are omitted.

[0086] In this embodiment, the first magnetic field application unit 500 has an electromagnet 520 instead of the first permanent magnet 510. The electromagnet 520 is mounted around the nozzle 320 in the injection device 300. The magnetic field of the electromagnet 520 passes through the nozzle 320.

[0087] The electromagnet 520 is electrically connected to a power source (not shown). In this embodiment, power is supplied to the electromagnet 520 during the injection process in the magnet manufacturing method. Power is not supplied to the electromagnet 520 when manufacturing is not taking place or during the extraction process of the manufacturing method.

[0088] In this embodiment, during the magnetization process, a magnetic field is applied to the bonded magnet material by the electromagnet 520 of the first magnetic field application unit 500. The electromagnet 520 of the first magnetic field application unit 500 applies a magnetic field to the bonded magnet material as it passes through the nozzle 320. After the injection process, the electromagnet 520 stops applying the magnetic field.

[0089] <Operation of the Embodiment> The operation of this embodiment will now be explained. The electromagnet 520 generates a magnetic field in accordance with the supplied power. This allows the first magnetic field application unit 500 to switch the magnetic field on and off, and to adjust the strength of the magnetic field.

[0090] <Effects of the Embodiment> The effects of this embodiment will now be explained. (3-1) In the magnetization process, a magnetic field is applied to the bonded magnet material by the electromagnet 520. With this configuration, the electromagnet 520 can be used to switch the magnetic field applied to the bonded magnet material on and off, and to adjust the strength of the magnetic field.

[0091] <Variation> The refrigeration apparatus, fluid machinery, rotating electric machinery, magnet manufacturing apparatus, and magnet manufacturing method of the present disclosure may also be modified in ways other than those described above, such as those shown below, and in combination of at least two mutually non-inconsistent modifications.

[0092] The refrigeration system may be equipped with a rotating electric machine. Examples of refrigeration systems in this modification include air conditioners, refrigerators, and heat pump systems. The refrigeration system has a refrigeration cycle. A rotating electric machine is applied to the compressor, etc., which constitute the refrigeration cycle of the refrigeration system. According to this modification, the performance of the refrigeration system can be improved by using a rotating electric machine with improved rotational characteristics.

[0093] • Although fluid machinery was described as a blower, fluid machinery can be any device that converts mechanical energy into fluid energy, such as a pump or compressor.

[0094] • The description above has focused on a blower with a fan, but the blower may also have a fan.

[0095] • Although the rotating electric machine was described as a motor, it could also be a generator.

[0096] The shape of the cavity 460 is not limited to the examples of the embodiments, but is determined according to the shape of the molded product 100. If the molded product 100 is a ring magnet, the cavity 460 is a cylindrical space. If the molded product 100 is a plate-shaped magnet, the cavity 460 is a plate-shaped space.

[0097] In the magnetization process, a magnetic field may be applied to the bonded magnet material in the cylinder 310. In this modified example, the first magnetic field application unit 500 applies a magnetic field to the cylinder 310. The first permanent magnet 510 of the first magnetic field application unit 500 is mounted around the cylinder 310 in the injection device 300.

[0098] The first magnetic field application unit 500 may apply a magnetic field along the first direction D1 into the nozzle 320.

[0099] Although it has been explained that the second magnetic field application unit 600 applies a magnetic field using the second permanent magnet 610, the second magnetic field application unit 600 may also apply a magnetic field using an electromagnet.

[0100] The first magnetic field application unit 500 may be provided on the first mounting unit 411. The first magnetic field application unit 500 may be provided on the spool bush 430.

[0101] The second magnetic field application section 600 may be provided in a part other than the protrusion 426. For example, the second magnetic field application section 600 may be located in the part of the second movable type 422 that overlaps with the cavity 460 in a direction perpendicular to the first direction D1.

[0102] As shown in Figure 8, in the third embodiment, the electromagnet 520 of the first magnetic field application unit 500 may be provided on the mold 400. In this modified example, the electromagnet 520 is arranged on the first movable mold 421. The magnetic field of the electromagnet 520 passes through the spool 470. A magnetic field is applied inside the spool 470 by the magnetic field of the electromagnet 520.

[0103] As shown in Figure 9, the core material 101 is inserted into the cavity 460 of the mold 400, and the void 102 provided in the core material 101 may be filled with bonded magnet material. Figure 9 is a view of the cavity 460 from a first direction D1. The second movable mold 422 and the third movable mold 423 are also schematically shown. In this modified method for manufacturing a magnet, the core material 101 is inserted into the cavity 460 before the injection process. The core material 101 is made of laminated electromagnetic steel sheets, for example. The core material 101 has a void 102 which is a hole extending in the first direction D1. The gate 490 is located on the void 102. In the injection process, bonded magnet material is injected into the void 102. As shown in Figure 10, in this modified method, a molded product 100X is manufactured. The molded product 100X is a motor core. The molded product 100X is, for example, an inner rotor. The molded product 100X has a core material 101 and a magnet part 103 disposed in the void 102 of the core material 101. The magnet part 103 is a bonded magnet formed by the magnet manufacturing method of this modified example. A gate mark 104 is formed on the magnet part 103.

[0104] The embodiments and variations thereof of the refrigeration apparatus, fluid machinery, rotating electric machine, magnet manufacturing apparatus, and magnet manufacturing method 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 refrigeration apparatus, fluid machinery, rotating electric machine, magnet manufacturing apparatus, and magnet manufacturing method described in the claims. [Explanation of Symbols]

[0105] 10...Refrigeration equipment, 40...Fluid machinery, 50...Rotating electric machine, 70...Stator, 90...Rotor, 92...Magnet, 200...Manufacturing equipment, 300...Injection equipment, 310...Cylinder, 320...Nozzle, 400...Mold, 460...Cavity, 470...Spool, 471...Inlet, 472...Spool outlet, 480...Runner, 490...Gate, 500...First magnetic field application unit, 510...First permanent magnet, 520...Electromagnet, 600...Second magnetic field application unit.

Claims

1. A method for manufacturing magnets, The process includes an injection step of injecting a bonded magnet material containing magnetic powder from an injection device (300) into a mold (400), The mold (400) has a cavity (460), a spool (470) into which the bonded magnet material is injected from the injection device (300), and a runner (480) that connects from the spool outlet (472) of the spool (470) to a plurality of gates (490) that open into the cavity (460). The injection process is as follows: A magnetization step in which a magnetic field is applied to the bonded magnet material upstream of the spool outlet (472) in the flow path of the bonded magnet material, The process includes an orientation step of applying a magnetic field to the bonded magnet material in the cavity (460), A method for manufacturing magnets.

2. The injection device (300) includes a cylinder (310) for storing the bonded magnet material and a nozzle (320) for connecting the cylinder (310) to an injection port (471) which is the open end of the spool (470) of the mold (400). In the magnetization step, a magnetic field is applied to the bonded magnet material in the cylinder (310) or the nozzle (320). A method for manufacturing a magnet according to claim 1.

3. The spool (470) is provided with an injection port (471) into which the bonded magnet material is injected from the injection device (300). In the magnetization step, a magnetic field is applied to the bonded magnet material between the injection port (471) and the spool outlet (472). A method for manufacturing a magnet according to claim 1.

4. In the magnetization step, a magnetic field is applied to the bonded magnet material by a permanent magnet (510). A method for manufacturing a magnet according to claim 1.

5. In the magnetization step, a magnetic field is applied to the bonded magnet material by an electromagnet (520). A method for manufacturing a magnet according to claim 1.

6. Stator (70) and, A rotor (90) and a rotor are provided, A magnet (92) manufactured by the magnet manufacturing method described in any one of claims 1 to 5 is used in at least one of the stator (70) and the rotor (90). Rotating electric machine.

7. The rotating electric machine (50) according to claim 6, Fluid machinery.

8. The rotating electric machine (50) according to claim 6, Refrigeration equipment.

9. A magnet manufacturing apparatus (200), An injection device (300) for injecting bonded magnet material containing magnetic powder, A mold (400) having a cavity (460), a spool (470) into which the bonded magnet material is injected from the injection device (300), and a runner (480) connecting from the spool outlet (472) of the spool (470) to a plurality of gates (490) opening into the cavity (460), A first magnetic field application unit (500) applies a magnetic field upstream of the spool outlet (472) in the flow path of the bonded magnet material, The device comprises a second magnetic field application unit (600) that applies a magnetic field to the cavity (460), Magnet manufacturing equipment.

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