Method for supplying magnetic materials, and apparatus for manufacturing magnetic molded products.

Abstract

The magnetic material for the magnetic molded body is appropriately supplied into the mold. [Solution] The method for supplying magnetic material includes a preparation step of preparing a concave mold K1 and a screw feeder 20, and a supply step of supplying the magnetic material 2 into the recess K1a of the concave mold K1 using the screw feeder 20.

Description

Technical Field

[0001] The present disclosure relates to a method for supplying a magnetic material and an apparatus for manufacturing a magnetic molded body.

Background Art

[0002] Permanent magnets such as bonded magnets and sintered magnets are formed using magnetic molded bodies. Patent Documents 1 and 2 disclose an example of a method for manufacturing a magnetic molded body. In the manufacture of a magnetic molded body, first, a material containing magnet powder is supplied into a mold. Subsequently, a punch is used to compress the material in the mold to form a magnetic molded body.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to mold a magnetic molded body, a material is supplied into a mold. However, depending on the material, it may be difficult to appropriately supply the material into the mold. For this reason, the present disclosure will describe a method for supplying a magnetic material that can appropriately supply the magnetic material of a magnetic molded body into a mold and an apparatus for manufacturing a magnetic molded body.

Means for Solving the Problems

[0005] One aspect of the present disclosure is [1] "A method for supplying a magnetic material, comprising supplying a magnetic material containing magnetic powder into a concave mold for forming a magnetic molded body by compressing the magnetic material, the method comprising: a preparation step of preparing the concave mold and a screw feeder; and a supply step of supplying the magnetic material into the recess of the concave mold using the screw feeder."

[0006] A screw feeder is configured to transport magnetic material by rotating a screw to push out the magnetic material. Therefore, screw feeders can suppress supply problems such as the inability to supply the required amount of magnetic material, resulting in excess magnetic material remaining inside. Thus, this method of supplying magnetic material, by using a screw feeder, allows for the appropriate supply of magnetic material into the mold for magnetic molded products.

[0007] The above method for supplying magnetic material may also be [2] "the method for supplying magnetic material described in [1] above, wherein in the preparation step, the concave mold is positioned so that the opening of the recess faces upward, and in the supply step, the magnetic material is transported by the screw feeder to the upper position of the opening of the recess, and then the magnetic material is dropped from the upper position of the opening of the recess to supply the magnetic material into the recess." In this method for supplying magnetic material, the magnetic material is transported by the screw feeder to the upper position of the opening. Therefore, in this method for supplying magnetic material, the accumulation of magnetic material around the opening of the recess during supply can be suppressed, while the required amount of magnetic material can be supplied more reliably into the recess.

[0008] The above method for supplying magnetic material may also be [3] "the method for supplying magnetic material according to [2] above, wherein in the preparation step, the screw feeder is positioned such that, when the recess is viewed from above, the discharge port of the screw feeder for the magnetic material is located at the opening edge of the recess." For example, after supplying magnetic material into a concave recess, a punch is inserted into the opening of the recess to compress the magnetic material and form a magnetic molded body from the magnetic material. In this method for supplying magnetic material, when the recess is viewed from above, the discharge port of the screw feeder is located at the opening edge of the recess. Therefore, in this method for supplying magnetic material, interference between the punch and the screw feeder can be suppressed when the punch is inserted into the recess from above in order to form a magnetic molded body.

[0009] The above method for supplying magnetic material may also be [4] "the method for supplying magnetic material according to any one of [1] to [3] above, wherein in the supply step, a predetermined amount of the magnetic material necessary for molding the magnetic molded body is supplied into the recess from a hopper provided on the screw feeder by rotating the screw of the screw feeder a predetermined number of times." In this case, the required amount of magnetic material can be supplied into the recess by controlling the number of rotations of the screw in this method for supplying magnetic material.

[0010] The above method for supplying magnetic material may also be [5] "a method for supplying magnetic material according to any one of [1] to [3] above, further comprising a pre-supply step of supplying a predetermined amount of the magnetic material necessary for molding the magnetic molded body into a hopper provided in the screw feeder, wherein in the supply step, the predetermined amount of the magnetic material supplied into the hopper is supplied into the recess by the screw feeder." In this case, with this method for supplying magnetic material, the predetermined amount of magnetic material supplied into the hopper can be supplied into the recess simply by rotating the screw, making it easy to control the rotation of the screw.

[0011] The above method for supplying magnetic material may also be [6] "the method for supplying magnetic material according to any one of [1] to [5] above, wherein the magnetic material is a compound containing the magnetic powder and a thermosetting resin." For example, such a compound may have poor fluidity. Therefore, in this method for supplying magnetic material, such a compound can be supplied more appropriately into the recess by using a screw feeder.

[0012] Another aspect of the present disclosure is [7] "A magnetic molded body manufacturing apparatus for manufacturing a magnetic molded body by compressing a magnetic material containing magnetic powder, comprising: a mold unit having a concave mold and a punch inserted into a recess of the concave mold; a screw feeder for supplying the magnetic material into the recess; and a compression mechanism for compressing the magnetic material in the mold unit."

[0013] This magnetic molding manufacturing apparatus can supply magnetic material into the recessed part of a concave mold using a screw feeder. The screw feeder is configured to transport the magnetic material by rotating a screw to push it out. Therefore, the screw feeder can suppress supply problems such as not being able to supply the required amount of magnetic material, resulting in some magnetic material remaining inside. In this way, by using a screw feeder, this magnetic molding manufacturing apparatus can properly supply the magnetic material into the mold and manufacture magnetic moldings. [Effects of the Invention]

[0014] According to various aspects of this disclosure, the material for a magnetic molded body can be appropriately supplied into the mold. [Brief explanation of the drawing]

[0015] [Figure 1] Figure 1 is a schematic diagram showing an example of a manufacturing apparatus for a magnetic molded body according to an embodiment. [Figure 2] Figure 2 is a schematic diagram of the concave and screw feeders shown in Figure 1, viewed from above. [Figure 3] FIG. 3 is a schematic view showing a state where a magnetic material is compressed to form a magnetic molded body.

Embodiments for Carrying Out the Invention

[0016] Hereinafter, exemplary embodiments will be described with reference to the drawings. In each figure, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[0017] [Overall Configuration of the Manufacturing Apparatus] The manufacturing apparatus 1 shown in FIG. 1 is an apparatus for manufacturing a magnetic molded body from a magnetic material (raw material) containing magnetic powder. The magnetic molded body is obtained by molding a magnetic material into a specific shape and is an object having magnetic properties. The magnetic molded body may be used, for example, in the manufacture of permanent magnets such as bonded magnets and sintered magnets.

[0018] As shown in FIGS. 1 and 2, the manufacturing apparatus 1 includes a compression mechanism 10, a screw feeder 20, a magnetic field generation mechanism 30, and a mold unit K. The mold unit K is supplied with the magnetic material 2 of the magnetic molded body containing magnetic powder. The magnetic powder contained in the magnetic material 2 is, for example, an Nd-Fe-B based magnet (an alloy such as Nd2Fe 14 B, etc.), a samarium-iron-nitrogen based magnet (an alloy such as Sm2Fe 17 N3, etc.), a samarium cobalt based magnet (an alloy such as Sm2Co 17 etc.), a praseodymium based magnet (an alloy such as PrCo5, etc.), or a ferrite magnet. For example, an Nd-Fe-B based magnet is used as a material for a magnetic molded body that becomes a bonded magnet and a sintered magnet. On the other hand, since the crystal structure of a Sm-Fe-N based magnet is liable to deteriorate at a high temperature (about 500°C), it is difficult to manufacture a sintered magnet from a Sm-Fe-N based magnet. Therefore, a Sm-Fe-N based magnet is used as a material for a magnetic molded body that becomes a bonded magnet that can be manufactured by heating at a low temperature at which the crystal structure is maintained (thermosetting of a thermosetting resin mixed with magnetic powder).

[0019] When a bonded magnet is manufactured using a magnetic molded body, the magnetic material 2 may contain, in addition to the magnet powder, components such as a thermosetting resin, a curing agent, a curing accelerator (curing catalyst), a silane coupling agent, a wax (lubricant), a flame retardant, and an organic solvent. The magnetic material 2 for bonded magnets may further contain a thermoplastic resin in addition to the thermosetting resin. Thus, the magnetic material 2 may be a compound containing magnet powder and a thermosetting resin. When a sintered magnet is manufactured using a magnetic molded body, the magnetic material 2 may contain, in addition to the magnet powder, components such as a wax (lubricant). The magnetic material 2 may be pre-mixed to a substantially uniform state. The magnetic material 2 may be a powder, a tablet, or a paste.

[0020] The compression mechanism 10 compresses the magnetic material 2 supplied to the mold unit K to form a magnetic molded body 2A (see Figure 3) from the magnetic material 2. The compression mechanism 10 includes a first pressurizing mechanism 11 and a second pressurizing mechanism 12. The first pressurizing mechanism 11 and the second pressurizing mechanism 12 face each other with a predetermined distance between them. Hereinafter, the direction in which the first pressurizing mechanism 11 and the second pressurizing mechanism 12 face each other will be referred to as the Z-axis direction (first direction). One direction perpendicular to the Z-axis direction will be referred to as the X-axis direction, and the direction perpendicular to both the Z-axis direction and the X-axis direction will be referred to as the Y-axis direction. In this embodiment, the Z-axis direction will be the vertical direction. In the vertical direction (Z-axis direction), the side on which the first pressurizing mechanism 11 is provided relative to the second pressurizing mechanism 12 will be referred to as "up," and the opposite side will be referred to as "down."

[0021] The first pressing mechanism 11 is a device that moves the upper punch P2 of the mold unit K along the Z-axis direction. The first pressing mechanism 11 may be a hydraulic mechanism. The upper punch P2 may be connected to the first pressing mechanism 11. The second pressing mechanism 12 is a device that moves the lower punch P1 of the mold unit K along the Z-axis direction. The lower punch P1 may be connected to the second pressing mechanism 12. The first pressing mechanism 11 moves the upper punch P2 toward the second pressing mechanism 12 side. The second pressing mechanism 12 moves the lower punch P1 toward the first pressing mechanism 11 side. Thereby, the magnetic material 2 in the mold unit K is compressed to form the magnetic molded body 2A. Note that the compression mechanism 10 may compress the magnetic material 2 in the mold unit K by moving the upper punch P2 with the first pressing mechanism 11 while fixing the lower punch P1. Alternatively, the compression mechanism 10 may compress the magnetic material 2 in the mold unit K by moving the lower punch P1 with the second pressing mechanism 12 while fixing the upper punch P2.

[0022] As shown in FIGS. 1 and 2, the mold unit K includes a die K10, a lower punch P1, and an upper punch (punch) P2. The die K10 has a through-hole K10a extending in the Z-axis direction. The through-hole K10a is, as an example in the present embodiment, a hole having a rectangular cross-section. The cross-sectional shape of the through-hole K10a is not particularly limited. The die K10 is disposed between the first pressing mechanism 11 and the second pressing mechanism 12 of the compression mechanism 10. In the through-hole K10a, the opening on the second pressing mechanism 12 side is defined as an opening KH1, and the opening on the first pressing mechanism 11 side is defined as an opening KH2.

[0023] The lower punch P1 has a columnar shape extending in the Z-axis direction. The cross-sectional shape of the lower punch P1 matches the cross-sectional shape of the through hole K10a provided in the die K10. In this embodiment, the lower punch P1 has a rectangular prism shape as an example. The lower punch P1 has an end face P1a. The end face P1a is the surface facing the first pressurizing mechanism 11 (end face P2a of the upper punch P2) in the Z-axis direction. The lower punch P1 is inserted into the through hole K10a from the opening KH1 of the die K10, with the end face P1a side leading. In the lower punch P1, the end opposite to the end face P1a is pressed by the second pressurizing mechanism 12.

[0024] The upper punch P2 has a columnar shape extending in the Z-axis direction. The cross-sectional shape of the upper punch P2 matches the cross-sectional shape of the through hole K10a provided in the die K10. The upper punch P2 has an end face P2a. The end face P2a is the surface facing the second pressurizing mechanism 12 (end face P1a of the lower punch P1) in the Z-axis direction. The upper punch P2 is inserted into the through hole K10a from the opening KH2 of the die K10, with the end face P2a side leading. In the upper punch P2, the end opposite to the end face P2a is pressed by the first pressurizing mechanism 11.

[0025] A concave mold K1 having a recess K1a is formed by a die K10 and a lower punch P1 with its end face P1a side inserted into a through hole K10a. The recess K1a is formed by the inner surface of the through hole K10a of the die K10 and the end face P1a of the lower punch P1. The concave mold K1 is a mold for forming a magnetic molded body 2A by compressing a magnetic material 2 containing magnetic powder with an upper punch P2. The concave mold K1 is positioned between the first pressurizing mechanism 11 and the second pressurizing mechanism 12 such that the opening KH2, which is the opening of the recess K1a, faces upward.

[0026] The screw feeder 20 supplies the magnetic material 2 into the recess K1a of the concave mold K1. The screw feeder 20 comprises a flow channel section 21, a screw 22, a drive unit 23, and a hopper 24. Note that in Figure 2, the hopper 24 is omitted to show the area around the flow channel section 21. The flow channel section 21 forms a flow channel 21a that transports the magnetic material 2 into the recess K1a of the concave mold K1. The flow channel section 21 is, for example, a cylindrical (for example, cylindrical) member having a flow channel 21a inside. The flow channel section 21 extends, for example, in the X-axis direction. The flow channel section 21 is provided, for example, on the surface of the die K10 on the opening KH2 side (on the surface of the concave mold K1 on the first pressurizing mechanism 11 side).

[0027] The flow channel section 21 has an inlet 21b and an outlet 21c. The outlet 21c is provided at one end of the flow channel section 21 in the direction of extension (here, for example, the X-axis direction). The inlet 21b is provided near the end of the flow channel section 21 opposite to the side where the outlet 21c is provided in the direction of extension. The inlet 21b is a through hole that connects the inner circumferential surface and the outer circumferential surface of the flow channel section 21. The inlet 21b is provided in the upper part of the flow channel section 21. A hopper 24 is connected to the inlet 21b portion of the flow channel section 21. Magnetic material 2 is supplied into the hopper 24. Magnetic material 2 is introduced into the flow channel 21a of the flow channel section 21 from the hopper 24 via the inlet 21b. The magnetic material 2 in the flow channel 21a of the flow channel section 21 is discharged from the outlet 21c.

[0028] The screw 22 is positioned within the flow path 21a of the flow path section 21. The screw 22 extends in the direction of extension of the flow path section 21. The screw 22 has, for example, spiral-shaped conveying blades attached to a rotating shaft. The screw 22 is rotationally driven by the drive unit 23. By being rotationally driven by the drive unit 23, the screw 22 pushes the magnetic material 2 in the flow path 21a toward the discharge port 21c. The screw feeder 20 can control the amount of magnetic material 2 discharged from the discharge port 21c by the number of rotations of the screw 22.

[0029] As shown in Figure 2, the screw feeder 20 is positioned such that, when viewed from above, the discharge port 21c of the screw feeder 20 is located at the opening edge of the recess K1a (the edge of the opening KH2) of the recess K1a provided in the concave K1. In other words, when viewed from above, the position of the discharge port 21c of the screw feeder 20 and the position of the opening edge of the recess K1a coincide. This allows the screw feeder 20 to directly feed (supply) the magnetic material 2 into the recess K1a of the concave K1 from the discharge port 21c, while suppressing the accumulation of the magnetic material 2 discharged from the discharge port 21c on the upper surface of the concave K1 on the opening KH2 side.

[0030] Here, the arrangement of the discharge port 21c of the screw feeder 20 to be located at the opening edge of the recess K1a means that, when viewed from above, the discharge port 21c of the screw feeder 20 does not extend inward (into the opening KH2) of the recess K1a. Furthermore, the arrangement of the discharge port 21c of the screw feeder 20 to be located at the opening edge of the recess K1a includes a configuration in which the discharge port 21c of the screw feeder 20 is located slightly outward (outside the opening KH2) from the position of the opening edge of the recess K1a. Here, the arrangement of the discharge port 21c of the screw feeder 20 to be located at the opening edge of the recess K1a means that the magnetic material 2 discharged from the discharge port 21c of the magnetic material 2 does not accumulate on the upper surface on the opening KH2 side of the concave K1, and the magnetic material 2 can be directly fed (supplied) from the discharge port 21c into the recess K1a of the concave K1.

[0031] The magnetic field generating mechanism 30 applies a magnetic field to the magnetic material 2 within the mold unit K. The magnetic field generating mechanism 30 comprises a first coil 31 and a second coil 32. The first coil 31 and the second coil 32 are positioned to sandwich the mold unit K. The magnetic field generating mechanism 30 further includes a power supply mechanism. The power supply mechanism is electrically connected to the first coil 31 and the second coil 32, respectively. The power supply mechanism allows for the free control of the direction and absolute value of the first current generated in the first coil 31 and the direction and absolute value of the second current generated in the second coil 32. The power supply mechanism is not shown in the figure.

[0032] A magnetic field H (see Figure 3) is combined from the magnetic field generated in the first coil 31 and the magnetic field generated in the second coil 32. The combined magnetic field H may be applied to the magnetic material 2 in the mold unit K. Alternatively, the magnetic field H generated by only one of the coils, the first coil 31 and the second coil 32, may be applied to the magnetic material 2 in the mold unit K. For example, the direction of the magnetic field H may be perpendicular to the opposing direction (Z-axis direction) of the first pressurizing mechanism 11 and the second pressurizing mechanism 12. However, the direction of the magnetic field H is not limited. The direction of the magnetic field H may be changed by changing the arrangement of the first coil 31 and the second coil 32, respectively. In this embodiment, as an example, the first coil 31 and the second coil 32 are arranged so as to sandwich the mold unit K in the X-axis direction. In this embodiment, as an example, the direction of the magnetic field H applied to the magnetic material 2 in the mold unit K is in the X-axis direction.

[0033] [Method for supplying magnetic molded bodies] A method for supplying magnetic material 2 into a recess K1a of a concave shape K1 will be described. The method for supplying magnetic material 2 into a concave shape K1 includes a preparation step and a supply step.

[0034] In the preparation step, the concave mold K1 and the screw feeder 20 are prepared as shown in Figures 1 and 2. Here, the concave mold K1 is placed between the first pressurizing mechanism 11 and the second pressurizing mechanism 12 of the compression mechanism 10 so that the opening KH2 of the concave mold K1a faces upward. Also, the screw feeder 20 is positioned so that when the concave mold K1 is viewed from above, the discharge port 21c of the screw feeder 20 is located at the opening edge of the concave mold K1 (the edge of the opening KH2).

[0035] In the supply process, as shown in Figures 1 and 2, the magnetic material 2 is supplied into the recess K1a of the concave mold K1 by a screw feeder 20. More specifically, in the supply process, the magnetic material 2 is transported by the screw feeder 20 to the upper position of the opening KH2 of the recess K1a, and then the magnetic material 2 is dropped from the upper position of the opening KH2 of the recess K1a to supply the magnetic material 2 into the recess K1a.

[0036] For example, in the supply process, a predetermined amount of magnetic material 2 necessary for molding the magnetic molded body 2A may be supplied from the hopper 24 into the recess K1a of the concave mold K1 by rotating the screw 22 of the screw feeder 20 a predetermined number of times.

[0037] The method for supplying the magnetic material 2 into the concave mold K1 may further include a pre-supply step. In the pre-supply step, a predetermined amount of magnetic material 2 necessary for molding the magnetic molded body 2A is supplied in advance into the hopper 24 of the screw feeder 20. Subsequently, in the supply step, the predetermined amount of magnetic material 2 supplied into the hopper 24 may be supplied into the recess K1a of the concave mold K1 by the screw feeder 20.

[0038] After the method for supplying the magnetic material 2 into the recessed mold K1 is performed, a molding process is carried out. In the molding process, as shown in Figure 3, the magnetic material 2 supplied into the recess K1a of the recessed mold K1 is compressed using the compression mechanism 10 to form a magnetic molded body 2A. Here, the first pressurizing mechanism 11 and the second pressurizing mechanism 12 are used to move at least one of the lower punch P1 and the upper punch P2 along the Z-axis so that the first pressurizing mechanism 11 and the second pressurizing mechanism 12 move closer to each other. As a result, the magnetic material 2 in the recess K1a is compressed by the lower punch P1 and the upper punch P2 to become a magnetic molded body 2A.

[0039] Furthermore, in this embodiment, the molding process may include a magnetic field application process in which a magnetic field H is applied to the magnetic material 2 using a magnetic field generation mechanism 30. In the molding process for molding the magnetic molded body 2A, the power supply device may generate a magnetic field in the first coil 31 and the second coil 32 by supplying current to them, thereby executing the magnetic field application process. The magnetic field H is combined from the magnetic field generated in the first coil 31 and the magnetic field generated in the second coil 32. The combined magnetic field H is applied to the magnetic material 2 in the mold unit K. The magnetization direction of the entire magnetic molded body 2A is substantially or perfectly parallel to the direction of the magnetic field H applied to the magnetic material 2.

[0040] In this embodiment, a magnetic field H is applied to the magnetic material 2 in the mold unit K using a magnetic field generation mechanism 30 while the magnetic material 2 in the mold unit K is compressed by a lower punch P1 and an upper punch P2. Each magnetic particle in the magnetic material 2 is magnetized and rotated by the magnetic field H, and the easy magnetization axis of the magnetic domain in each magnetic particle is oriented along the magnetic field H. In other words, each magnetic particle in the magnetic material 2 is oriented so that its magnetization direction is approximately parallel to the magnetic field H. If each magnetic particle is a single crystal grain (single magnetic domain), the magnetization direction of each magnetic particle is the same as the direction in which the easy magnetization axis of each magnetic particle extends. A magnetic molded body 2A is manufactured through the above process.

[0041] The application of the magnetic field H may be terminated at the same time as the molding pressure reaches its maximum value. The application of the magnetic field H may be terminated when the molding pressure begins to decrease. The application of the magnetic field H may be terminated at the same time as the compression of the magnetic material 2 in the mold unit K ends. The magnetic field H applied to the magnetic material 2 may be a static magnetic field (a continuous, constant magnetic field). The magnetic field H may be a pulsed magnetic field (a pulsed magnetic field). The start and end of the application of the magnetic field H may be performed by the control unit of the power supply mechanism controlling the power supplied to the first coil 31 and the second coil 32.

[0042] When the magnetic molded body 2A is used in the manufacture of bonded magnets, the magnetic molded body 2A may be demagnetized by applying a magnetic field (reverse magnetic field) that is oriented in the opposite direction to the magnetic field H described above. Even in the demagnetized magnetic molded body 2A, the state in which the easy magnetization axis of each magnetic particle in the magnetic molded body 2A is oriented in the same direction as the magnetic field H is maintained. Subsequently, the demagnetized magnetic molded body 2A may be heated to form a cured product of the magnetic molded body 2A. When the magnetic molded body 2A is used in the manufacture of bonded magnets, the magnetic material 2 may contain a thermosetting resin. Therefore, a cured product of the magnetic molded body 2A may be formed by thermosetting the thermosetting resin in the magnetic molded body 2A. Subsequently, the cured product of the magnetic molded body 2A may be magnetized by applying a magnetic field that is oriented in the same direction as the magnetic field H to the cured product of the magnetic molded body 2A. By magnetizing the cured product of the magnetic molded body 2A, a permanent magnet (an anisotropic magnet magnetized in a specific direction) is obtained. The magnetic molded body 2A formed from the magnetic material 2 through the molding process may be a completed anisotropic bonded magnet. In this case, the demagnetization process described above may not be performed.

[0043] When the magnetic molded body 2A is used in the manufacture of a sintered magnet, the magnetic molded body 2A may be sintered to form a sintered body. The sintered body may be used as a permanent magnet (an anisotropic magnet magnetized in a specific direction). Before the magnetic molded body 2A is sintered, the magnetic molded body 2A may be degreased by heating it at a temperature lower than the sintering temperature of the magnetic molded body 2A. The sintered body may be magnetized by applying a magnetic field that is oriented in the same direction as the magnetic field H described above. The magnetized sintered body may be used as a permanent magnet.

[0044] Next, the manufactured magnetic molded body 2A is removed from the mold unit K. Here, the concave mold K1 is composed of a die K10 and a lower punch P1. Therefore, for example, after the upper punch P2 is withdrawn from the concave mold K1, the magnetic molded body 2A may be removed from the concave mold K1 by pushing it out from the through hole K10a of the die K10 with the lower punch P1.

[0045] [Effects and Effects] As described above, the manufacturing apparatus 1 for the magnetic molded body 2A can supply the magnetic material 2 into the recess K1a of the concave mold K1 using a screw feeder 20. The screw feeder 20 is configured to transport the magnetic material 2 by rotating a screw 22 to push out the magnetic material 2. Therefore, the screw feeder 20 can suppress the occurrence of supply problems, such as the inability to supply the required amount of magnetic material 2, resulting in some magnetic material 2 remaining inside (in the flow path 21a). Thus, in this magnetic material supply method and manufacturing apparatus 1, by using the screw feeder 20, the magnetic material 2 of the magnetic molded body 2A can be appropriately supplied into the mold (in the recess K1a of the concave mold K1).

[0046] In the preparation step, the concave mold K1 is positioned so that the opening KH2 of the recess K1a of the concave mold K1 faces upward. In the supply step, the magnetic material 2 is transported by the screw feeder 20 to the upper position of the opening KH2 of the recess K1a of the concave mold K1, and then the magnetic material 2 is dropped from the upper position of the opening KH2 of the recess K1a to supply the magnetic material 2 into the recess K1a. In this case, this method of supplying the magnetic material 2 suppresses the accumulation of magnetic material 2 around the opening KH2 of the recess K1a during supply, while more reliably supplying the required amount of magnetic material 2 into the recess K1a of the concave mold K1.

[0047] In the preparation step, the screw feeder 20 is positioned such that, when the recess K1a is viewed from above, the discharge port 21c of the screw feeder 20 is located at the opening edge of the recess K1a (the edge of the opening KH2). For example, after supplying magnetic material 2 into the recess K1a of the concave mold K1, the upper punch P2 is inserted into the opening KH2 of the recess K1a to compress the magnetic material 2 and form a magnetic molded body 2A from the magnetic material 2. In this method of supplying magnetic material 2, when the recess K1a provided in the concave mold K1 is viewed from above, the discharge port 21c of the screw feeder 20 is located at the opening edge of the recess K1a. Therefore, in this method of supplying magnetic material 2, interference between the upper punch P2 and the screw feeder 20 (flow channel 21) when the upper punch P2 is inserted into the recess K1a from above to form the magnetic molded body 2A can be suppressed.

[0048] In the supply process, a predetermined amount of magnetic material 2 required for molding the magnetic molded body 2A may be supplied from the hopper 24 into the recess K1a of the concave mold K1 by rotating the screw 22 of the screw feeder 20 a predetermined number of times. In this case, the required amount of magnetic material 2 can be supplied into the recess K1a of the concave mold K1 by controlling the number of rotations of the screw 22.

[0049] The method for supplying the magnetic material 2 may further include a pre-supply step in which a predetermined amount of magnetic material 2 necessary for molding the magnetic molded body 2A is supplied in advance into the hopper 24 of the screw feeder 20. In this case, with this method of supplying the magnetic material 2, the predetermined amount of magnetic material 2 supplied into the hopper 24 can be supplied into the recess K1a of the concave mold K1 simply by rotating the screw 22, making it easier to control the rotation of the screw 22.

[0050] The magnetic material 2 may be a compound containing magnetic powder and a thermosetting resin. For example, such a magnetic material 2 may have poor fluidity. Therefore, in this method of supplying the magnetic material 2, by using a screw feeder 20, such a magnetic material 2 (compound) can be supplied more appropriately into the recess K1a of the concave mold K1. [Explanation of symbols]

[0051] 2...Magnetic material, 2A...Magnetic molded body, 10...Compression mechanism, 20...Screw feeder, 21c...Discharge port, 22...Screw, 24...Hopper, K1...Concave mold, K1a...Recess, P2...Upper punch (punch).

Claims

1. A method for supplying magnetic material, comprising supplying the magnetic material containing magnetic powder into a concave mold for forming a magnetic molded body by compressing the magnetic material, Preparation steps include preparing the aforementioned concave mold and screw feeder, A method for supplying a magnetic material, comprising a supply step of supplying the magnetic material into the concave recess using the screw feeder.

2. In the preparation step described above, the concave mold is positioned so that the opening of the recess faces upward, The method for supplying a magnetic material according to claim 1, wherein in the supply step, the magnetic material is transported by the screw feeder to the upper position of the opening of the recess, and then the magnetic material is dropped from the upper position of the opening of the recess to supply the magnetic material into the recess.

3. The method for supplying magnetic material according to claim 2, wherein in the preparation step, the screw feeder is positioned such that, when the recess is viewed from above, the discharge port of the screw feeder for the magnetic material is located at the opening edge of the recess.

4. The method for supplying magnetic material according to claim 1, wherein in the supply step, a predetermined amount of the magnetic material necessary for molding the magnetic molded body is supplied into the recess from a hopper provided on the screw feeder by rotating the screw of the screw feeder a predetermined number of times.

5. The process further includes a pre-supply step of supplying a predetermined amount of the magnetic material necessary for molding the magnetic molded body into a hopper provided in the screw feeder, The method for supplying magnetic material according to claim 1, wherein in the supply step, a predetermined amount of the magnetic material supplied into the hopper is supplied into the recess by the screw feeder.

6. The method for supplying a magnetic material according to any one of claims 1 to 5, wherein the magnetic material is a compound containing the magnetic powder and a thermosetting resin.

7. A magnetic molding apparatus for manufacturing a magnetic molded body by compressing a magnetic material containing magnetic powder, A mold unit having a concave mold and a punch inserted into the recess of the concave mold, A screw feeder that supplies the magnetic material into the recess, A manufacturing apparatus for a magnetic molded body, comprising a compression mechanism for compressing the magnetic material within the mold unit.

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