Collection member for collecting magnetic foreign matter, manufacturing method for granular material, collection device, and rod-shaped magnet member

Abstract

Provided is a collection member for collecting magnetic foreign matter from a granular material, the collection member comprising: a conveyance path for conveying the granular material; and a rod-shaped magnet member disposed on the conveyance path such that the longitudinal direction thereof intersects the conveyance direction of the granular material, wherein the rod-shaped magnet member comprises a magnet and a magnetic linear structure disposed on the outer peripheral surface of the magnet. Also provided is a magnet member having a ferromagnetic linear structure on a surface thereof.

Description

Collecting member for collecting magnetic foreign matter, method for producing powder and granular material, collecting device, and rod-shaped magnet member

[0001] The present disclosure relates to a collecting member for collecting magnetic foreign matter, a method for producing powder and granular material, a collecting device, and a rod-shaped magnet member.

[0002] Various foreign matters may be mixed into powder and granular material, and several methods for removing magnetic foreign matters such as magnetic foreign matters from powder and granular material are known. For example, there is a method in which a rod-shaped magnet member is disposed in a conveying path of powder and granular material to collect and remove magnetic foreign matter by magnetic force. However, this method has insufficient recovery efficiency because the contact area between the powder and granular material and the magnet member is limited. As another method, there is a method in which a magnetic mesh is disposed in a conveying path of powder and granular material, and magnetic foreign matter is collected and removed while the powder and granular material pass through the magnetic mesh. However, pressure loss occurs while the powder and granular material pass through the magnetic mesh. If the openings of the magnetic mesh are enlarged in order to prevent an increase in pressure loss, the attraction force by magnetic force decreases.

[0003] A method for removing magnetic foreign matter from powder and granular material is also applied to a method for removing magnetic foreign matter from resin pellets. Patent Document 1 discloses an iron remover that can efficiently recover iron scraps mixed in powder and granular material by vertically stacking a plurality of iron removal frames holding a plurality of bar magnets arranged in parallel, and arranging the bar magnets in a staggered manner in the falling direction of the powder and granular material.

[0004] Japanese Utility Model Laid-Open No. 5-82512

[0005] In the method of passing powder and granular material through the rod-shaped magnet described above, since the magnet is rod-shaped, many magnets can be installed in the iron remover, but the ability of each magnet to collect mixed metal is low, so the recovery rate of magnetic foreign matter is low. In addition, in the method of passing powder and granular material through a magnetic mesh, when large powder and granular material such as resin pellets are used, pressure loss is likely to occur, and when the opening diameter is increased according to the size of the resin pellets, the attraction force by magnetic force decreases. Furthermore, in this method, wires and the like constituting the magnetic mesh may be cut by the passage of powder and granular material.

[0006] In view of these circumstances, this disclosure aims to provide a collection member capable of efficiently collecting magnetic foreign matter from powders and granules, a collection method thereof, a collection apparatus thereof, and a rod-shaped magnet member.

[0007] Some embodiments of the present disclosure are illustrated below. [1] A collecting member for collecting magnetic foreign matter from granular material, comprising a transport path for transporting the granular material and a rod-shaped magnetic member disposed in the transport path and having its longitudinal direction intersecting the transport direction of the granular material, wherein the rod-shaped magnetic member comprises a magnet and a magnetic linear structure disposed on the outer circumferential surface of the magnet. [2] The collecting member according to [1], wherein the magnetic linear structure has a plurality of linear shapes spaced apart from each other. [3] The collecting member according to [1] or [2], wherein the magnetic linear structure has a mesh shape formed by the intersection of a plurality of linear shapes. [4] The collecting member according to any one of [1] to [3], wherein the granular material comprises at least one selected from the group consisting of granules, powders, crushed material, and fibrous material. [5] The collecting member according to any one of [1] to [4], wherein the magnetic foreign matter is contained in the granular material separately from the main material of the granular material. [6] The collecting member according to any one of [1] to [5], wherein the average particle size of the magnetic foreign matter is 50 μm or more. [7] The collecting member according to any one of [1] to [6], wherein a plurality of the rod-shaped magnet members are arranged spaced apart from each other in a direction in which their longitudinal directions intersect with respect to the conveying direction of the powder and granules, and at least one of the plurality of rod-shaped magnet members comprises the magnetic linear structure. [8] The collecting member according to any one of [1] to [7], wherein a plurality of the rod-shaped magnet members are arranged spaced apart from each other in a direction in which their longitudinal directions intersect with respect to the conveying direction of the powder and granules, and comprises a plurality of such rod-shaped magnet member units, with at least one of the plurality of rod-shaped magnet member units comprising the magnetic linear structure. [9] The collecting member according to any one of [1] to [8], wherein the cross-section of the rod-shaped magnet member is circular and has a diameter of 20 to 30 mm.

[10] The collecting member according to any one of [1] to [9], wherein the rod-shaped magnet member comprises a magnet and a case for housing the magnet, and the magnetic linear structure is provided on the surface of the case.

[11] The collecting member according to any one of [1] to

[10] , wherein the rod-shaped magnet member is a rod-shaped magnet member having a ferromagnetic linear structure on its surface.

[12] A rod-shaped magnet member having a ferromagnetic linear structure on its surface.

[13] A bar-shaped magnet member according to

[12] , comprising a magnet portion and a covering portion, wherein the covering portion has the ferromagnetic linear structure.

[14] A bar-shaped magnet member according to

[12] or

[13] , comprising a magnet portion and a covering portion, wherein the covering portion is a linear ferromagnetic material and is disposed on the surface of the magnet portion.

[15] A bar-shaped magnet member according to

[12] or

[13] , comprising a magnet portion and a covering portion, wherein the covering portion is a magnetic material member having a surface having the ferromagnetic linear structure and is disposed on the surface of the magnet portion.

[16] A bar-shaped magnet member according to any one of

[12] to

[15] , wherein the ferromagnetic linear structure is a plurality of linear shapes spaced apart from each other.

[17] A bar-shaped magnet member according to any one of

[12] to

[15] , wherein the ferromagnetic linear structure is a mesh shape formed by the intersection of a plurality of linear shapes.

[18] A method for producing a powder or granular material from which magnetic foreign matter has been removed, comprising: a transport path for transporting the powder or granular material; a rod-shaped magnetic member disposed in the transport path and having a longitudinal direction intersecting the transport direction of the powder or granular material, wherein the rod-shaped magnetic member comprises a magnet and a magnetic linear structure disposed on the outer surface of the magnet, and the method for producing a powder or granular material comprises a collection member for transporting the powder or granular material to the transport path of the collection member, wherein the magnetic foreign matter is collected from the powder or granular material by the magnetic force of the rod-shaped magnetic member causing the magnetic foreign matter to be attracted to the transport path.

[19] A collection device for collecting magnetic foreign matter from powder or granular material, comprising: a supply unit for supplying the powder or granular material; a transport path for transporting the powder or granular material supplied from the supply unit; and a collection unit for collecting the magnetic foreign matter collected in the transport path, wherein a rod-shaped magnetic member is arranged in the transport path such that its longitudinal direction intersects the transport direction of the powder or granular material, and the rod-shaped magnetic member comprises a magnet and a magnetic linear structure arranged on the outer circumferential surface of the magnet.

[0008] According to this disclosure, it is possible to provide a collection member capable of efficiently collecting magnetic foreign matter from powders and granules, a collection method thereof, a collection apparatus thereof, and a rod-shaped magnet member.

[0009] Figure 1 is a schematic cross-sectional view of an example of a collecting member of the first embodiment. Figure 2A is a perspective view showing an example of an arrangement of a bar-shaped magnet member of the first embodiment. Figure 2B is a perspective view showing an example of an arrangement of a bar-shaped magnet member of the first embodiment. Figure 3A is a perspective view of an example of a bar-shaped magnet member of the first embodiment. Figure 3B is a cross-sectional view of an example of a bar-shaped magnet member of the first embodiment in the Y-plane. Figure 4A is a top view showing an example of a magnetic linear structure of the first embodiment. Figure 4B is a cross-sectional view showing an example of a magnetic linear structure of the first embodiment. Figure 5A is a top view of an example of a collecting member of the first embodiment. Figure 5B is a front view of an example of a collecting member of the first embodiment. Figure 5C is a side view of an example of a collecting member of the first embodiment. Figure 6A is a cross-sectional view of one embodiment of a bar-shaped magnet member of the second embodiment. Figure 6B is a cross-sectional view of one embodiment of a bar-shaped magnet member of the second embodiment. Figure 6C is a cross-sectional view of one embodiment of the bar-shaped magnet member according to the second embodiment. Figure 6D is a cross-sectional view of one embodiment of the bar-shaped magnet member according to the second embodiment. Figure 6E is a cross-sectional view of one embodiment of the bar-shaped magnet member according to the second embodiment.

[0010] The following describes some embodiments of this disclosure. The examples in the following description do not limit this disclosure.

[0011] [First Embodiment] According to the first embodiment, a collection member capable of efficiently collecting magnetic foreign matter from powders and granules is provided. Several embodiments of a collection member for collecting magnetic foreign matter from powders and granules will be described with reference to the drawings. The drawings may differ from the actual dimensional ratios in order to make the features of this disclosure easier to understand. Also, the materials and the like exemplified in the description of the drawings are examples only, and this disclosure is not limited to them.

[0012] <First Embodiment> The first embodiment will be described below with reference to the drawings. Figure 1 is a schematic cross-sectional view showing an example of a collection member of the first embodiment.

[0013] The collection member 1 comprises a transport path 4 for transporting powder granules 3, and a rod-shaped magnetic member 100 arranged in the transport path 4 with its longitudinal direction intersecting the transport direction of the powder granules 3. The rod-shaped magnetic member 100 comprises a magnet 110 and a magnetic linear structure 120 arranged on the outer circumferential surface of the magnet 110.

[0014] Magnetic foreign matter can be collected from the powder granules 3 using the collection member 1. In the example shown in Figure 1, the powder granules 3 mainly consist of non-magnetic particles 3a and contain a small amount of magnetic foreign matter 3b. The magnetic foreign matter 3b is contained in the powder granules 3 separately from the non-magnetic particles 3a, which are the main material. Depending on the application of the powder granules 3, the magnetic foreign matter 3b may be treated as an impurity, so it is preferable to collect and remove the magnetic foreign matter 3b from the powder granules 3. Magnetic foreign matter 3b may be mixed into the powder granules 3 during the manufacturing process, originating from the raw materials of the powder granules, the manufacturing equipment for producing the powder granules, the manufacturing equipment for producing articles using the powder granules, etc.

[0015] The granular material 3 may include at least one selected from the group consisting of granules, powders, crushed materials, and fibrous materials. In particular, it can be preferably applied to collect magnetic foreign matter that may be contained in the granules. Examples of granules include pellets, granulated materials, tablets, etc. The dimensions of the granules are not particularly limited, but for example, in the case of pellets, the average diameter may be 1.0 to 5.0 mm and the average length may be 1.5 to 10.0 mm.

[0016] The main raw material for the powder granule 3 may be either a non-magnetic inorganic material or an organic material, or a combination thereof. Examples of inorganic materials include ceramics, mineral grains, glass, metal particles, aggregated particles, crushed materials, and fibrous materials. Examples of organic materials include resins, and may be resin compounds. The resin may consist of a single material or a composite material of two or more resins. The resin compound may be a composite material of resin and an inorganic material, and examples include glass fiber-containing resin compounds and carbon material-containing resin compounds.

[0017] If the powder material 3 contains a resin, the resin is preferably a thermoplastic resin. Examples of thermoplastic resins include crystalline thermoplastic resins such as polyacetal resin, polyarylene sulfide resin such as polyphenylene sulfide resin, polybutylene terephthalate resin, polyethylene terephthalate resin, and polyamide resin. These may be used individually or as a composite resin of two or more types. These resins may also be composite resins of these resins with other materials.

[0018] It is preferable that magnetic foreign matter is included in the powder or granular material separately from the main material of the powder or granular material. The magnetic foreign matter may be metal particles, fine metal powder aggregated into particulate matter, etc. The magnetic foreign matter may also be attached to the main material of the powder or granular material. For example, the magnetic foreign matter may be attached to the surface of pellets made of resin or the like.

[0019] The magnetic foreign matter can be any material that becomes magnetized when placed in a magnetic field. For example, the magnetic foreign matter can be a material that is magnetized via the magnetic linear structure 120 during the process of passing through the transport path 4 of the collection member 1. More specifically, the magnetic foreign matter can be a material that, either on its own or attached to the main material, is attracted to the outer surface of the rod-shaped magnet member 100 by the magnetic force of the rod-shaped magnet member 100. Specifically, the magnetic foreign matter can be soft magnetic materials such as iron, nickel, cobalt, or alloys thereof. The average particle size of the magnetic foreign matter may be 10 to 1,000 μm, 40 to 500 μm, or 50 μm to 200 μm. In the case of iron, the average particle size of the magnetic foreign matter is preferably 50 μm or more. By having the particle size of the magnetic foreign matter within the above range, the collection member 1 can collect the magnetic foreign matter more efficiently. Here, the average particle size of magnetic foreign matter is determined by observing a predetermined number of magnetic foreign matter particles using an optical microscope or the like, and taking the average value of the longest diameter of the magnetic foreign matter particles.

[0020] The collection member 1 includes a pipe 2, and a transport path 4 is formed inside the pipe 2. The pipe 2 is preferably a cylindrical or rectangular pipe with both bottom surfaces open. The pipe 2 is preferably installed so that the openings at both ends are aligned vertically so that the powder granules 3 can easily fall by their own weight, but it may be inclined as long as the powder granules 3 can fall by their own weight and do not get stuck between the multiple rod-shaped magnet members 100. The inclination angle can be adjusted by the magnetic force of the rod-shaped magnet members 100, the size and supply amount of the powder granules 3, etc., and may be, for example, 0 to 45° with respect to the vertical direction. The inclination angle may be ~45° with respect to the horizontal direction and the inclined surface may be gentle. In this case, the powder granules 3 inside the pipe 2 may be pushed out by airflow.

[0021] The collection member 1 is equipped with a plurality of bar-shaped magnetic members 100 in the transport path 4. The plurality of bar-shaped magnetic members 100 increase the frequency with which magnetic foreign matter 3b from the transported powder granules 3 comes into contact with the bar-shaped magnetic members 100, thereby improving the collection efficiency of magnetic foreign matter 3b. The plurality of bar-shaped magnetic members 100 are arranged spaced apart from each other in a direction in which their longitudinal directions intersect with the transport direction of the powder granules 3, and these form a bar-shaped magnetic member unit. In the illustrated example, the bar-shaped magnetic members 100 are arranged parallel to each other in a direction perpendicular to the transport direction of the powder granules 3. The spacing between adjacent bar-shaped magnetic members 100 is preferably five times or more the average diameter of the powder granules 3. As will be described later, when a plurality of bar-shaped magnetic units are arranged in multiple stages, the spacing between the bar-shaped magnetic members 100 constituting the upper bar-shaped magnetic unit in the vertical direction is preferably less than or equal to the diameter of the bar-shaped magnetic members 100 constituting the lower bar-shaped magnetic unit. By arranging the bar-shaped magnet members 100 spaced apart from each other at the above intervals, it is possible to prevent the powder granules 3 from getting stuck between adjacent bar-shaped magnet members 100, while increasing the proportion of contact between the powder granules 3 and the bar-shaped magnet members 100, thereby more efficiently capturing magnetic foreign matter 3b contained in the powder granules 3. Note that the number and arrangement method of the bar-shaped magnet members 100 are not limited to the illustrated example. Furthermore, in a set of bar-shaped magnet member units, it is sufficient for at least one of the multiple bar-shaped magnet members to have a magnetic linear structure, but it is preferable for two or more, preferably all, bar-shaped magnet members to each have a magnetic linear structure.

[0022] The collection member 1 preferably comprises a plurality of rod-shaped magnetic member units arranged spaced apart from each other along the conveying direction X1 of the powder and granular material. More preferably, the plurality of rod-shaped magnetic member units are arranged in multiple stages along the conveying direction X1 of the powder and granular material. Figure 2A shows an example in which spaced-apart rod-shaped magnetic member units are arranged in multiple stages in the same orientation with respect to the conveying direction X1. Figure 2B shows an example in which parallel rod-shaped magnetic member units are arranged in multiple stages in a direction perpendicular to the conveying direction X1. When the rod-shaped magnetic member units are arranged in multiple stages in the same orientation, it is preferable that each rod-shaped magnetic member 100 is arranged in a staggered pattern with respect to the conveying direction X1. By installing rod-shaped magnetic members 100 in the conveying path 4 as described above, the opportunities for the powder and granular material 3 to come into contact with the rod-shaped magnetic members 100 as it is conveyed along the conveying path 4 can be increased, and magnetic foreign matter 3b contained in the powder and granular material 3 can be collected more efficiently. Furthermore, in a multi-stage bar-shaped magnet member unit, it is sufficient to have at least one bar-shaped magnet member with a magnetic linear structure in the multiple bar-shaped magnet member unit, but it is preferable that two or more, preferably all, bar-shaped magnet member units each have a bar-shaped magnet member with a magnetic linear structure. More preferably, 80% or more, 90% or more, or all bar-shaped magnet members in the multi-stage bar-shaped magnet member unit have a magnetic linear structure. Note that by forming the bar-shaped magnet member unit on the upstream side in the conveying direction with bar-shaped magnet members without a magnetic linear structure, and the bar-shaped magnet member unit on the downstream side in the conveying direction with bar-shaped magnet members with a magnetic linear structure, magnetic foreign matter that could not be collected on the upstream side can be collected on the downstream side, thereby improving collection efficiency.

[0023] Figure 3A shows a perspective view of an example of a bar-shaped magnet member 100, and Figure 3B shows a cross-sectional view along the Y line. The bar-shaped magnet member 100 comprises a magnet 110 and a magnetic linear structure 120 arranged on the outer surface of the magnet. However, as shown in Figure 3B, it may also comprise a magnet 110 and a case 130 that houses the magnet 110, with the magnetic linear structure 120 being provided on the surface of the case 130. In Figure 3B, the case 130 is arranged inside the magnetic linear structure 120, but the case 130 may be arranged outside the magnetic linear structure 120 and cover the entire surface of the magnetic linear structure 120. The bar-shaped magnet member 100 may be a bar-shaped magnet member having a ferromagnetic linear structure on its surface. By having a ferromagnetic linear structure, the bar-shaped magnet member 100 can have a high magnetic flux density while not having a large difference in magnetic flux density throughout. This reduces the area of ​​low magnetic flux density, making it easier for magnetic foreign matter 3b to be attracted to the entire outer surface of the rod-shaped magnet member 100, thereby increasing the collection efficiency of magnetic foreign matter 3b. In this disclosure, the magnet is also referred to as the magnet part, and the case as the covering part. As shown in Figure 3B, the cross-section of the rod-shaped magnet member 100 is preferably circular, but it may also be elliptical, triangular, quadrilateral, teardrop-shaped, etc. If the cross-section is circular, the diameter is preferably 20 to 30 mm. The rod-shaped magnet member 100 should have enough magnetic force to generate a magnetic field on its outer surface and attract magnetic foreign matter 3b to its outer surface. If there are multiple rod-shaped magnet members 100 used in the collection member, the cross-sections of each magnet may be different, and if they are circular, they may have different diameters, but it is preferable that the rod-shaped magnet members 100 for each unit have the same shape. The magnet 110 may be a permanent magnet, such as KS steel, MK steel, NKS steel, Alnico magnet, ferrite magnet, cobalt magnet, neodymium magnet, etc. The rod-shaped magnet member 100 should be made of a material that can appropriately attract magnetic foreign matter 3b that may be contained in the powder granules 3 to its outer surface, and the magnetic force should be adjusted accordingly. The magnet 110 may also be an electromagnet. If it is an electromagnet, the magnetic foreign matter 3b attracted to the outer surface can be recovered more easily by turning the magnetic field on and off. Also, if it is an electromagnet, it is possible to adjust the magnetic force according to the type of powder granules 3.Case 130 can be any magnetic material, such as a soft magnetic material like iron, nickel, cobalt, or an alloy thereof.

[0024] The rod-shaped magnet member 100 may be fixed or rotatable, but it is preferable that it be fixed.

[0025] The magnet 110 may be a single magnet with one end in the longitudinal direction being the north pole and the other end being the south pole. Alternatively, the magnet 110 may be a plurality of magnets arranged longitudinally so that the same poles face each other. In order to obtain a stronger magnetic force from the magnet 110 on the outer surface of the rod-shaped magnet member 100, it is preferable to place the magnet 110 close to the conveying surface. However, in this case, a large difference in magnetic flux density may occur on the outer surface of the rod-shaped magnet member 100. Since the powder granules 3 may come into contact with the outer surface of the rod-shaped magnet member 100 in clumps, magnetic foreign matter 3b adhering to the powder granules 3 passing through areas of low magnetic flux density is less likely to be attracted to the outer surface. By interposing the magnetic linear structure 120 between the rod-shaped magnet member 100 and the outer surface of the rod-shaped magnet member 100, the difference in magnetic flux density from the rod-shaped magnet member 100 is mitigated, the area of ​​low magnetic flux density is reduced, and magnetic foreign matter 3b is more easily attracted over the entire outer surface, thereby increasing the collection rate of magnetic foreign matter 3b.

[0026] The magnetic linear structure 120 may be a structure having multiple linear shapes, such as linear shapes or mesh shapes. A first example of a linear shape is a structure having multiple linear shapes spaced apart from each other, preferably with the multiple linear shapes being parallel to each other, and preferably with approximately equal spacing between them. The width of one linear shape may be, for example, 0.1 to 1.0 mm. The narrower the width of the linear shapes and the spacing between them are within the above ranges, the more homogenized the magnetic field of the magnet 110 can be. The spacing between adjacent linear shapes may be, for example, 0.1 to 2.0 mm. The shape of the linear shapes may have a rectangular, trapezoidal, semicircular, or mountain-shaped cross-section in the short-side direction. From the viewpoint of homogenizing the magnetic field of the rod-shaped magnet member 100, it is preferable that the shape of the linear shapes be approximately the same in the longitudinal direction.

[0027] A second example of a linear shape is one in which multiple linear shapes intersect to form a mesh shape. For example, a linear shape in a first direction and a linear shape in a second direction may intersect each other to form a mesh shape. The angle of intersection is not particularly limited but may be between 30 and 120°, or between 90° and 5°. The details of the linear shapes in each direction may be those described in the first example above. For example, the mesh shape may be a grid shape, and the width and spacing of the linear shapes in the first direction and the linear shapes in the second direction may be approximately the same, and they may be perpendicular to each other.

[0028] The magnetic linear structure 120 may penetrate in the thickness direction, exposing the magnet 110 or case 130, or it may have an uneven surface formed on its surface or back surface. The magnetic linear structure 120 may have a non-magnetic material filled in the penetrating portion or recess. This provides surface smoothness to the magnetic linear structure 120, further improving the conveying efficiency of the powder granules 3. It also increases the material strength of the magnetic linear structure 120. The non-magnetic material to be filled is preferably a resin material. In both cases, with and without the non-magnetic material, the magnetic linear structure 120 may have a coating layer on its linear surface. The coating layer may be a surface smoothing agent such as silicone resin or fluororesin.

[0029] The magnetic linear structure 120 can be any magnetic material, such as a soft magnetic material like iron, nickel, cobalt, or an alloy thereof. However, it is preferable that the magnetic linear structure 120 be made of a material with a lower permeability than the magnetic force of the magnet 110. This homogenizes the magnetic flux density on the outer surface of the rod-shaped magnet member 100, thereby increasing the collection efficiency of magnetic foreign matter 3b.

[0030] In the example shown in Figure 3B, the magnetic linear structure 120 is formed on the outside of the case 130, but the magnetic linear structure 120 may be formed on the inside of the case 130. A top view of the unfolded magnetic linear structure 120 is shown in Figure 4A, and a cross-sectional view is shown in Figure 4B. In the example shown in this figure, the magnetic linear structure 120 has a grid shape formed by the intersection of a first linear shape formed in the longitudinal direction and a second linear shape formed in the short direction.

[0031] An example of a method for producing granular material 3 by collecting magnetic foreign matter 3b using a collection member 1 is described below. The granular material 3 supplied from the upstream side of the transport direction X1 of the transport path 4 falls downstream of the transport direction X1 due to its own weight. A rod-shaped magnet member 100 is placed in the transport path 4, and a magnetic field originating from the magnetic linear structure 120 is formed on the outer surface of the rod-shaped magnet member 100. As a result, the magnetic foreign matter 3b is attracted to the outer surface of the rod-shaped magnet member 100, the magnetic foreign matter 3b is removed, and the granular material 3 containing non-magnetic particles 3a is discharged from the downstream side of the transport direction X1 of the transport path 4. Since the magnetic linear structure 120 is provided between the outer surface of the rod-shaped magnet member 100 and the magnet 110, the difference in magnetic flux density is reduced across the entire outer surface of the rod-shaped magnet member 100. As a result, a uniform magnetic field can be formed on the outer surface of the rod-shaped magnet member 100, and magnetic foreign matter 3b can be efficiently attracted and collected across the entire outer surface of the rod-shaped magnet member 100.

[0032] In the illustrated example above, the magnetic linear structure 120 is formed to cover the case 130 that houses the magnet 110, but the design is not limited to this. For example, the magnetic linear structure 120 may be used as a magnetic mesh to cover the magnet 110, and the outside of that may be covered by the case 130.

[0033] <Second Embodiment> A second embodiment of the collection member will be described with reference to Figure 5. Figure 5A is a top view of an example of the collection member 200, Figure 5B is a front view thereof, and Figure 5C is a side view thereof. The collection member 200 comprises a bar-shaped magnet member unit having a plurality of bar-shaped magnet members 100 arranged parallel to each other at equal intervals, arranged in two stages in the same orientation, and a support plate 140 that supports the bar-shaped magnet members 100. As shown in Figure 5C, at the end of each bar magnet unit, adjacent bar-shaped magnet members 100 have different magnetic poles. The collection member 200 is installed inside a vertically positioned rectangular tube, with the two stages of bar-shaped magnet member units arranged vertically. When powder or granular material is supplied from the top of the collection member 200, the pellets fall due to their own weight, and magnetic foreign matter is collected from the bottom of the rectangular tube by the magnetic force of the bar-shaped magnet members 100.

[0034] According to another embodiment, a method for manufacturing powder is provided, which includes transporting powder to the transport path of the collection member using a collection member, the collection member comprising a transport path for transporting powder and granular material, and a rod-shaped magnetic member disposed in the transport path with its longitudinal direction intersecting the transport direction of the powder and granular material, wherein the rod-shaped magnetic member comprises a magnet and a magnetic linear structure disposed on the outer surface of the magnet, and magnetic foreign matter is collected from the powder and granular material by the action of magnetic foreign matter being attracted to the transport path by the magnetic force of the rod-shaped magnetic member.

[0035] <Collection device> According to yet another embodiment, a collection device for collecting magnetic foreign matter from powders and granules is provided, comprising a supply unit for supplying powders and granules, a transport path for transporting the powders and granules supplied from the supply unit, and a collection unit for collecting magnetic foreign matter collected in the transport path, wherein a rod-shaped magnetic member is arranged in the transport path with its longitudinal direction intersecting the transport direction of the powders and granules, and the rod-shaped magnetic member comprises a magnet and a magnetic linear structure arranged on the outer surface of the magnet.

[0036] [Second Embodiment] According to the second embodiment, a rod-shaped magnetic member that can be used in the collecting member of the first embodiment is provided. One embodiment thereof will be described in detail below.

[0037] According to this embodiment, a rod-shaped magnet member having a ferromagnetic linear structure on its surface can be provided.

[0038] The magnetic material of the rod-shaped magnetic member may be a permanent magnet, such as KS steel, MK steel, NKS steel, Alnico magnet, ferrite magnet, cobalt magnet, neodymium magnet, etc. The rod-shaped magnetic member may also be an electromagnet.

[0039] The bar-shaped magnet member may consist of multiple bar-shaped magnet members arranged so that like poles face each other, or it may be a single bar-shaped magnet member with one end being the north pole and the other the south pole, but it is preferable that multiple bar-shaped magnet members are arranged together. When the bar-shaped magnet member is a single magnet, the magnetic flux density decreases near the middle of the bar-shaped magnet member, which can result in a large difference in magnetic flux density between each pole. By having a ferromagnetic linear structure for the bar-shaped magnet member, the difference in magnetic flux density is mitigated, the region with low magnetic flux density decreases, and a high magnetic flux density can be obtained with a small difference in magnetic flux density across the entire surface of the bar-shaped magnet member.

[0040] Examples of magnetic member shapes include prisms, cylinders, semicylinders, and elliptical prisms. Prisms may be polygonal prisms such as triangular prisms, square prisms, and pentagonal prisms, and may also be plate-shaped. For example, a rod-shaped magnetic member is preferred. A rod-shaped magnetic member has a long longitudinal direction, and its cross-sectional shape may be circular, elliptical, polygonal, etc. A rod-shaped magnetic member may have a ferromagnetic linear structure on its entire or partially circumferential surface. A rod-shaped magnetic member may have a ferromagnetic linear structure on its entire or partially longitudinal surface.

[0041] In this embodiment, the rod-shaped magnet member has a ferromagnetic linear structure on its surface. The ferromagnetic linear structure may be a structure comprising a plurality of linear shapes, such as linear shapes or mesh shapes. A first example of the linear shapes is a plurality of linear shapes spaced apart from each other, preferably the plurality of linear shapes are parallel to each other, and preferably the pitch of the plurality of linear shapes is approximately equal. The width of one linear shape may be, for example, 0.1 to 5.0 mm, 0.1 to 3.0 mm, 0.1 to 1.0 mm, 0.3 to 1.0 mm, or 0.5 to 1.0 mm. The spacing between adjacent linear shapes may be, for example, 0.1 to 4.0 mm, 0.1 to 2.0 mm, 0.3 to 2.0 mm, or 0.5 to 1.0 mm. The narrower the width of the linear shapes and the spacing between the linear shapes are within the above ranges, the more homogenized the magnetic field of the rod-shaped magnet member can be. The linear shape may have a rectangular, trapezoidal, semicircular, or V-shaped cross-section in the shorter direction. From the viewpoint of homogenizing the magnetic field of the bar-shaped magnet member, it is preferable that the linear shape is substantially the same in the longer direction.

[0042] A second example of a linear shape is one in which multiple linear shapes intersect to form a mesh shape. For example, a linear shape in the first direction and a linear shape in the second direction may intersect each other to form a mesh shape. The details of the linear shapes in each direction may be those described in the first example above. For example, the mesh shape may be a grid shape, and the width and spacing of the linear shapes in the first direction and the linear shapes in the second direction may be approximately the same, and they may be perpendicular to each other. Furthermore, it is preferable that the linear shapes in the first direction and the linear shapes in the second direction are provided at 0 to 30°, 60 to 90°, 90 to 120°, or 150 to 180° with respect to the N / S direction of the bar-shaped magnet member, respectively. In particular, it is preferable that they are provided at 90° or 180° with respect to the N / S direction. This can further mitigate the difference in magnetic flux density. It may also be 90°±5° or 180°±5°.

[0043] When a plurality of bar-shaped magnet members are used arranged side by side, a ferromagnetic linear structure may be formed on a predetermined surface of each bar-shaped magnet member, respectively, and these ferromagnetic linear structures may be arranged on the same plane. Further, a ferromagnetic linear structure may be integrally formed on the entire surface formed by combining a plurality of bar-shaped magnet members.

[0044] The bar-shaped magnet member may comprise a magnet part and a surface covering part. In this case, the ferromagnetic linear structure can be provided on the surface covering part. When a soft material is used for the magnet part, it may be difficult to process the surface of the magnet part, but by providing the surface covering part, the ferromagnetic linear structure can be provided by the surface covering part.

[0045] The magnet part is a part that is itself made of a material having magnetic force. The magnet part may be the magnet material described above, or may be an electromagnet.

[0046] The surface covering part means a member surrounding the magnet part. It is preferable that the surface covering part includes a portion formed of a ferromagnetic material. The ferromagnetic material may be, for example, iron, nickel, cobalt, alloys thereof, or the like. The alloy may be, for example, SUS430. Since the surface covering part covers the magnet part, the strength of the bar-shaped magnet member can be increased even when a soft magnet material is used for the magnet part. Further, for the surface covering part including a portion formed of a ferromagnetic material, the shape of the portion can be processed into the ferromagnetic linear structure for provision, or the surface of the portion can be processed into the ferromagnetic linear structure. Note that, from the viewpoint of increasing magnetic flux density, the surface covering part and the magnet part are preferably in contact with each other.

[0047] The surface covering part only needs to be provided on part or all of the surface of the magnet part. For example, when the magnet part is a quadrangular prism, the surface covering part can be provided on one surface, a plurality of surfaces, or the entire surface of the quadrangular prism. On one surface of the magnet part, the surface covering part only needs to be provided partially or entirely. For example, when the surface covering part itself is a ferromagnetic linear structure, the surface covering part only needs to be attached to the magnet part. In another example, the magnet part may be provided with a surface covering part having the ferromagnetic linear structure on the surface thereof.

[0048] As an example of the covering portion, it may be a linear ferromagnetic material disposed on the surface of the magnet portion. Examples of the linear ferromagnetic material include a wire and the like. When a wire is used, the cross-sectional diameter may be, for example, 0.1 to 5.0 mm, 0.1 to 3.0 mm, 0.1 to 1.0 mm, 0.3 to 1.0 mm, or 0.5 to 1.0 mm. The linear ferromagnetic material may be wound around the surface of the magnet portion. By winding the linear ferromagnetic material in one direction, a plurality of linear shapes spaced apart from each other can be formed on the surface of the magnet portion. By winding a plurality of linear ferromagnetic materials in directions intersecting each other, a plurality of linear shapes intersecting each other can be formed on the surface of the magnet portion. When the linear ferromagnetic material is wound around the surface of the magnet portion, the spacing between adjacent linear ferromagnetic materials is preferably within the range described above. When the covering portion is made of a linear ferromagnetic material, the ferromagnetic linear structure can be more easily formed on the surface of the magnet by disposing or winding the covering portion on the surface of the magnet portion. Furthermore, the strength of the rod-shaped magnet member can be further increased.

[0049] As another example of the covering portion, it may be a magnetic member provided with a surface having a ferromagnetic linear structure. The magnetic member only needs to be provided on part or all of the surface of the magnet portion. The magnetic member only needs to be provided with a surface having a ferromagnetic linear structure; for example, it may be plate-shaped, may be a casing, or may be a casing that covers the outer peripheral surface of the magnet portion. In another example, the magnetic member may be a box body, or may be a box body that covers the outer peripheral surface of the magnet portion and exposes the magnet portion from at least one surface. The magnetic member only needs to be provided on at least one surface of the magnet portion. Note that, from the viewpoint of increasing magnetic flux density, the covering portion and the magnet portion are preferably in contact with each other. In still another embodiment, when the covering portion is a casing, if the entire covering portion is formed of a ferromagnetic material, the rod-shaped magnet member cannot be accommodated therein, and therefore it is preferable that the covering portion includes a portion formed of a non-magnetic material. Examples of the non-magnetic material include resin materials, ceramic materials, glass, austenitic stainless steel, and the like.

[0050] The magnetic member preferably has a shape conforming to the surface of the magnet portion. For example, when disposed on a flat surface of the magnet portion, a planar magnetic member may be used, and when disposed on a curved surface of the magnet portion, a curved magnetic member may be used.

[0051] The magnetic material member may have a ferromagnetic linear structure on its surface. For example, a magnetic material member having the above-described linear shape formed on it can be used. In another example, the linear shape may be formed by forming through holes in the magnetic material member. As for the through holes, for example, multiple linear shapes that substitute for one another can be formed by providing long through holes in one direction, or through holes can be formed to form a mesh shape formed by the intersection of multiple linear shapes, such as a grid shape. The width of the linear shapes and the spacing between the linear shapes should be within the above-described range.

[0052] The magnetic material may have a ferromagnetic linear structure formed on it by processing while it is placed in the magnet section. In another example, the magnetic material may have a ferromagnetic linear structure already processed on it before being placed in the magnet section. These methods prevent damage to the magnetic material during processing when forming the ferromagnetic linear structure on the surface of the rod-shaped magnet material, even when using a soft magnetic material in the magnet section.

[0053] A rod-shaped magnet member comprising a magnetic portion and a covering portion may be used in the same way as the rod-shaped magnet member described above, by arranging multiple rod-shaped magnet members side by side or by using it as a single rod-shaped magnet member.

[0054] The ferromagnetic linear structure may be formed in the magnetic portion. For example, it may be formed on the surface of the portion exposed from the box-shaped outer covering.

[0055] When forming a ferromagnetic linear structure in the magnetic part, it is preferable to use a magnetic material with high strength.

[0056] If the magnet is exposed due to a through-hole being formed in the surface, it is preferable that the exposed portion be filled with a non-magnetic material. The non-magnetic material can be the one described above.

[0057] The magnetic portion and the surface portion may have a coating layer on the surface of the ferromagnetic linear structure. The coating layer may be the same as that of the magnetic linear structure in the first embodiment. By providing a coating layer, the material strength can be increased.

[0058] The rod-shaped magnet member may be housed in a container. Housed in a container can further enhance the durability of the rod-shaped magnet member. The container is not particularly limited, but it is preferably made of a non-magnetic material, and the non-magnetic materials described above can be used.

[0059] Some examples of the bar-shaped magnet members in this embodiment are shown below, but the dimensions and shape of the ferromagnetic linear structure are examples only and are not limited thereto.

[0060] Figure 6A is a cross-sectional view of an example in which a ferromagnetic wire 12a is wound around the magnet part 11 to form a ferromagnetic linear structure on the surface of the magnet part 11. In Figure 6A, the wire 12a is wound at equal intervals with gaps between them, but it may also be wound without gaps. The wire 12a may also be adhered to the magnet part. Furthermore, as shown in Figure 6B, the magnet part with the wire 12a wound around it may be housed in a container 13 made of a non-magnetic material. It is preferable that the container 13 is made of a non-magnetic material. Instead of housing it in a container 13, the surface of the wire 12a may be coated with a non-magnetic material, or the gaps between the wires 12a may be filled with a non-magnetic material. The non-magnetic material can be any of the materials mentioned above.

[0061] Figure 6C is a cross-sectional view of an example in which a magnetic part 11 and a covering part 12 are provided, and the surface of the covering part 12 covering the magnetic part 11 is processed to be uneven, thereby providing a covering part 12 with a surface having a ferromagnetic linear structure on the surface of the magnetic part 11. In the illustrated example, the covering part 12 has a ferromagnetic linear structure with multiple linear shapes on its surface, but it may be a ferromagnetic linear structure where multiple linear shapes intersect to form a mesh shape. Also, the ferromagnetic linear structure may penetrate in the thickness direction, exposing the magnetic part 11. Furthermore, the covering part 12 may have a box and a lid as separate components, and the ferromagnetic linear structure may be formed on the lid.

[0062] Figure 6D is a cross-sectional view of an example in which a ferromagnetic linear structure is formed on the surface of the magnet part 11 by processing the surface of the magnet part 11 to create an uneven surface, and this is housed in a box-shaped cover part 12. In the illustrated example, the magnet part 11 is not covered by the uneven surface of the cover part, but in order to further increase the material strength of the magnet part 11, the magnet part 11 may be completely covered by the cover part 12.

[0063] Figure 6E is a cross-sectional view of an example in which a plate-shaped member 12b having a linear shape on its surface is provided on the surface of the magnet part 11, thereby arranging a covering part 12 having a surface with a ferromagnetic linear structure on the surface of the magnet part 11, and further housing the magnet part 11 and the plate-shaped member 12b in a box-shaped container 13. The plate-shaped member 12b may be a mesh.

[0064] The rod-shaped magnet member of this embodiment has a high magnetic flux density and does not exhibit large differences in magnetic flux density throughout the entire rod-shaped magnet member, making it suitable for applications such as removing magnetic foreign matter such as metal fragments from powders and granules. Furthermore, it can be used in a wide range of fields as follows. For example, in magnetic separation and sorting equipment for ores, waste, and recycled materials, the uniformity of magnetic flux density contributes to uniform separation performance throughout the entire material being processed. In addition, in precision measuring instruments such as magnetic sensors, Hall elements, nuclear magnetic resonance (NMR), and electron spin resonance (ESR), a uniform magnetic field can be secured throughout the measurement area, contributing to improved measurement accuracy and reduced errors. In the field of magnetic recording, a uniform magnetic field can contribute to improved recording density and reliability in the magnetization process of hard disks, magnetic tapes, magneto-optical disks, etc. In the medical field, application to magnetic therapy devices can contribute to improved treatment effects and stabilized image quality. Furthermore, in particle accelerators and beam control devices, it can contribute to trajectory stabilization and improved focusing accuracy of electron beams and proton beams. In addition, in transport applications such as magnetic levitation transport devices and magnetic levitation trains (MAGLEV), a uniform magnetic field can contribute to achieving stable levitation and transport performance. Furthermore, in magnetization and heat treatment processes of magnetic materials, the ability to uniformly magnetize the entire product can contribute to reducing variations in product characteristics. Moreover, in research and development fields such as physics and materials science, the ability to apply a uniform magnetic field to the entire sample in magnetic property measurements, phase transition experiments, and magnetic refrigeration experiments can contribute to improving experimental accuracy.

[0065] The following describes specific embodiments of the present invention in detail with reference to examples, but the present invention is not limited to these examples.

[0066] To confirm that metal foreign objects falling under their own weight are collected by a magnet equipped with a magnetic linear structure, one method is to conduct an experiment using the collection member 200 shown in Figure 5 as a test apparatus.

[0067] As metallic foreign matter, iron sand with an average particle size of 100 μm is prepared.

[0068] Average particle size of iron sand: 100 μm; Diameter of rod-shaped magnet member: 24 mm; Length of rod-shaped magnet member: Upper row - 300 mm, Lower row - 250 mm; Spacing between rod-shaped magnet members: 43 mm; Surface magnetic flux density of magnets: Maximum 1.2 T; Feeding speed: 50 g / sec; Material of conveying surface: SUS; Number of experiments (N): 20

[0069] One experiment consists of the process of transporting 500 g of iron sand with an average particle size of 100 μm to a collection member. Twenty experiments are conducted, and the collection ratio (n2 / n1) of the collected iron sand mass (n2) to the total mass of iron sand supplied (n1) is calculated. In addition, the average collected mass, which is the average value of the proportion of iron sand collected over all 20 experiments, and its deviation of 3σ are calculated. In the comparative example without a linear structure, a rod-shaped magnet member enclosed in a SUS case with no surface processing is used. In the example with a linear structure, a SUS case with a linear structure attached to a rod-shaped magnet member similar to the one used in the comparative example without a linear structure is used. A schematic diagram of the linear structure is shown in Figure 4. The grid-like linear structure consists of linear shapes with a width of 0.21 mm, arranged at intervals of 0.848 mm in the transport direction and in directions perpendicular to the transport direction.

[0070] The above experiment shows that the embodiment with the linear structure collects more iron sand than the comparative example without the linear structure.

[0071] Although the present invention has been described with reference to several embodiments described above, the present invention is not limited to these embodiments. Various modifications can be made to the structure and details of the present invention within the scope of the invention. This disclosure relates to the subject matter described in Japanese Patent Application No. 2025-053942, filed on 27 March 2025, and the subject matter described in Japanese Patent Application No. 2025-169333, filed on 7 October 2025, all of which are incorporated herein by reference.

[0072] 1 Collection member, 2 Piping, 3 Powder / granular material, 3a Non-magnetic particles, 3b Magnetic foreign matter, 4 Conveyor path, 11 Magnet part, 12 Covering part, 12a Wire, 12b Plate-shaped member, 13 Container, 100 Bar-shaped magnet member, 110 Magnet, 120 Magnetic linear structure, 130 Case, 140 Support plate, 200 Collection member, X1 Conveyor direction, Y Cross-section

Claims

1. A collecting member for collecting magnetic foreign matter from powder or granular material, comprising a transport path for transporting the powder or granular material, and a rod-shaped magnetic member disposed in the transport path with its longitudinal direction intersecting the transport direction of the powder or granular material, wherein the rod-shaped magnetic member comprises a magnet and a magnetic linear structure disposed on the outer surface of the magnet.

2. The magnetic linear structure has a plurality of linear shapes spaced apart from each other, as described in claim 1.

3. The magnetic linear structure has a mesh shape formed by the intersection of multiple linear shapes, as described in claim 1 or 2.

4. The collecting member according to claim 1 or 2, wherein the granular material comprises at least one selected from the group consisting of granules, powders, crushed material, and fibrous material.

5. The collecting member according to claim 1 or 2, wherein the magnetic foreign matter is included in the powder separately from the main material of the powder.

6. The collection member according to claim 1 or 2, wherein the average particle size of the magnetic foreign matter is 50 μm or more.

7. The collecting member according to claim 1 or 2, wherein a plurality of the rod-shaped magnetic members are arranged spaced apart from each other in a direction in which their longitudinal directions intersect with respect to the conveying direction of the powder and granules, and at least one of the plurality of rod-shaped magnetic members comprises the magnetic linear structure.

8. The collecting member according to claim 1 or 2, wherein a plurality of the rod-shaped magnetic members are arranged spaced apart from each other in a direction in which their longitudinal directions intersect with respect to the conveying direction of the powder and granules, and the collecting member comprises a plurality of such rod-shaped magnetic member units, and at least one of the plurality of rod-shaped magnetic member units comprises the rod-shaped magnetic member having the magnetic linear structure.

9. The collecting member according to claim 1 or 2, wherein the cross-section of the rod-shaped magnetic member is circular and has a diameter of 20 to 30 mm.

10. The collecting member according to claim 1 or 2, wherein the rod-shaped magnetic member comprises a magnet and a case for housing the magnet, and the magnetic linear structure is provided on the surface of the case.

11. The collecting member according to claim 1 or 2, wherein the rod-shaped magnet member is a rod-shaped magnet member having a ferromagnetic linear structure on its surface.

12. A rod-shaped magnet member having a ferromagnetic linear structure on its surface.

13. The rod-shaped magnet member according to claim 12, comprising a magnetic portion and a covering portion, wherein the covering portion has the ferromagnetic linear structure.

14. The rod-shaped magnet member according to claim 12, comprising a magnetic portion and a covering portion, wherein the covering portion is a linear ferromagnetic material and is arranged on the surface of the magnetic portion.

15. The rod-shaped magnet member according to claim 12, comprising a magnet portion and a covering portion, wherein the covering portion is a magnetic material member having a surface having the ferromagnetic linear structure, and is arranged on the surface of the magnet portion.

16. The rod-shaped magnet member according to any one of claims 12 to 15, wherein the ferromagnetic linear structure is a plurality of linear shapes spaced apart from each other.

17. The rod-shaped magnet member according to any one of claims 12 to 15, wherein the ferromagnetic linear structure is a mesh shape formed by the intersection of a plurality of linear shapes.

18. A method for producing a powder or granular material from which magnetic foreign matter has been removed, comprising: a transport path for transporting the powder or granular material; a rod-shaped magnetic member disposed in the transport path and having its longitudinal direction intersecting the transport direction of the powder or granular material; wherein the rod-shaped magnetic member comprises a magnet and a magnetic linear structure disposed on the outer circumferential surface of the magnet, and the method includes transporting the powder or granular material to the transport path of the collection member; and the magnetic foreign matter is collected from the powder or granular material by the magnetic force of the rod-shaped magnetic member causing the magnetic foreign matter to be attracted to the transport path.

19. A collection device for collecting magnetic foreign matter from powder or granular material, comprising: a supply unit for supplying the powder or granular material; a transport path for transporting the powder or granular material supplied from the supply unit; and a collection unit for collecting the magnetic foreign matter collected in the transport path, wherein a rod-shaped magnetic member is arranged in the transport path such that its longitudinal direction intersects the transport direction of the powder or granular material, and the rod-shaped magnetic member comprises a magnet and a magnetic linear structure arranged on the outer circumferential surface of the magnet.

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