Powder classifying apparatus and classifying method using the same

Abstract

To provide a classifier capable of classifying powder with high throughput even in the case of classifying strongly adhesive powder.SOLUTION: A powder classifying device includes a member located in a flow path of a powder as a sample, a classification mesh for classifying a powder to be collected and a powder to be removed, and a vibration mechanism, wherein the member is located at a position substantially facing the classification mesh via a space, the space is filled with the conveyed powder, the vibration mechanism vibrates at least one of the member and the classification mesh, and a distance between the member and the classification mesh in the space is shorter than a distance in which the vibration is propagated to the powder filled in the space and the powder is sheared.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a powder classification device and a powder classification method using the same. [Background technology]

[0002] Patent Document 1 is known as a technology for classifying a powder sample into powder to be collected and foreign particle to be removed. Patent Document 1 describes "a foreign particle removal device comprising a substrate on which powder is placed and a classifying unit that classifies the powder to be collected and foreign particle to be removed, the classifying unit having a classification mesh, a vibrating unit that vibrates the substrate and / or the classification mesh, and a pressing unit that presses the classification mesh against the powder." [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2024-76041 Summary of the Invention [Problem to be solved by the invention]

[0004] According to the technology described in Patent Document 1, by pressing a classification mesh against the powder and vibrating it, it is possible to classify the powder while breaking down agglomerates, and it is said that it is possible to remove foreign matter even from highly adhesive powders. However, there is a possibility that the pressing of the classification mesh may actually compact the powder, and in such a case, the compacted powder will have difficulty passing through the classification mesh, which may result in a problem such as a decrease in the amount of powder that can be classified per unit time.

[0005] The present invention was made in consideration of these problems, and its purpose is to provide a classification device that can improve throughput (the amount of powder that can be classified per unit time) without compacting even highly adhesive powders. [Means for solving the problem]

[0006] The present application includes multiple means for resolving at least part of the above-mentioned problems, and an example thereof is as follows: That is, a powder classifying device including a member located in a flow path of a powder sample, a classification mesh that classifies powder to be collected and powder to be removed, and a vibration mechanism, wherein the member is positioned substantially opposite the classification mesh across a space, the space is filled with transported powder, the vibration mechanism vibrates at least one of the member and the classification mesh, and the distance between the member and the classification mesh in the space is shorter than the distance over which the vibrations can be transmitted to the powder filled in the space and shear the powder. [Effects of the Invention]

[0007] According to the present invention, even when a highly adhesive powder is classified, the powder is not compacted and throughput can be improved.

[0008] Problems, configurations, and effects other than those described above will become apparent from the following description of the preferred embodiments of the invention. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a top view showing an example of a schematic configuration of a classification device in Example 1. FIG. [Figure 2] 3 is a cross-sectional view showing an example of a detailed configuration of a supply unit 2 in the first embodiment. FIG. [Figure 3] 3 is a cross-sectional view showing an example of the detailed configuration of a classifying section 3 and a mesh 5 in Example 1. FIG. [Figure 4] 3 is a top view showing an example of the shape of an opening of a spacer 21 in the first embodiment. FIG. [Figure 5] 3 is a cross-sectional view showing an example of a detailed configuration of a cleaning unit 9 in the first embodiment. FIG. [Figure 6] FIG. 10 is a cross-sectional view showing an example of a detailed configuration of a classifying section 35 in a modified example. [Figure 7] 10 is a top view showing an example of the shape of an opening of a spacer 40 in a modified example. FIG. [Figure 8] FIG. 10 is a top view showing an example of a schematic configuration of a classification device in Example 2. [Figure 9] FIG. 10 is a cross-sectional view showing an example of the detailed configuration of a classifying section 47 and a mesh 55 in Example 2. [Figure 10] 10 is a top view showing an example of the shape of an opening of a spacer 61 in Example 2. FIG. [Figure 11] FIG. 10 is a cross-sectional view showing an example of a detailed configuration of a cleaning unit 48 in a second embodiment. [Figure 12A] FIG. 10 is a top view showing the configuration from a supply unit to a classification unit and a cleaning unit of a classification device in Example 3. [Figure 12B] FIG. 10 is a top view showing the configuration from the classifying section and cleaning section to the fine powder collecting section and coarse powder collecting section of the classifying device in Example 3. [Figure 13] FIG. 10 is a cross-sectional view showing an example of a detailed configuration of a supply unit 76 in the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The examples are illustrative of the present invention, and for clarity of explanation, appropriate omissions and simplifications have been made. The present invention can be implemented in various other forms. Unless otherwise specified, each component may be singular or plural.

[0011] In order to facilitate understanding of the invention, the position, size, shape, range, etc. of each component shown in the drawings may not represent the actual position, size, shape, range, etc. Therefore, the present invention is not necessarily limited to the position, size, shape, range, etc. disclosed in the drawings.

[0012] When there are multiple components with the same or similar functions, they may be described using the same reference numeral with different subscripts. When there is no need to distinguish between these multiple components, the subscripts may be omitted. [Example]

[0013] Example 1 will be described with reference to Figure 1. Figure 1 is a top view showing an example of a schematic configuration of a classification device in Example 1. The classification device 1 includes a supply unit 2, a classification unit 3, a fine powder collection unit 4, a mesh 5, a mesh frame 6, a hand 7, a linear motion mechanism 8, a cleaning unit 9, and a coarse powder collection unit 10.

[0014] Although not shown, the fine powder collection unit 4 and the coarse powder collection unit 10 each have a suction mechanism that draws in air to generate an airflow and a powder collection mechanism that captures the powder contained in the drawn air. The suction mechanism may be a blower or a vacuum cleaner. The powder collection mechanism may be a cyclone filter, a bag filter, or a cartridge filter. Alternatively, the fine powder collection unit 4 and the coarse powder collection unit 10 may each have a powder transport vacuum conveyor equipped with both a suction mechanism and a powder collection mechanism. Because the powder transport vacuum conveyor can discharge the collected powder from the bottom of the device, installing it above the tank or hopper of the next process in the production line can also transport the powder to the next process.

[0015] A powder sample is supplied from a supply unit 2 to a classification unit 3. In the classification unit 3, the powder is classified using a mesh 5, and fine powder that passes through the mesh 5 is collected in a fine powder collection unit 4, while coarse powder that does not pass through the mesh 5 remains on top of the mesh 5.

[0016] The mesh 5 is fixed to a mesh frame 6, and the mesh 5 and mesh frame 6 are moved from the classifying section 3 to a cleaning section 9 by a hand 7 and a linear motion mechanism 8. In the cleaning section 9, the coarse particles remaining on the mesh 5 are collected in a coarse particle collection section 10. Thereafter, the mesh 5 and mesh frame 6 are again moved by the hand 7 and linear motion mechanism 8 to the classifying section 3, where classification processing is carried out.

[0017] The supply unit 2 will be described with reference to FIG. 2. FIG. 2 is a cross-sectional view showing an example of the detailed configuration of the supply unit 2. The supply unit 2 includes a hopper 11, a constant-rate feeder 12, and a supply port 13. The powder is stored in the hopper 11 and is supplied to the supply port 13 by the constant-rate feeder 12 at a predetermined rate (amount supplied per unit time). If the supply rate of the powder supplied to the classifier 3 exceeds a predetermined value, clogging of the mesh 5 in the classifier 3 will occur. As such, the powder needs to be supplied to the classifier 3 at a constant rate below this predetermined value, so it is desirable to use the constant-rate feeder 12. The powder supplied to the supply port 13 is transported to the classifier 3 by the suction airflow generated by the suction mechanism of the fine powder recovery unit 4.

[0018] The classification unit 3 and mesh 5 will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing an example of the detailed configuration of the classification unit 3 and mesh 5. The classification unit 3 includes a lifting mechanism 14, a base 15, support columns 16, an aperture plate fixing frame 17, an aperture plate 18, a mask 19, a suction housing 20, a spacer 21, a vibration plate 22, a vibration plate fixing frame 23, support columns 24, and a vibrator 25.

[0019] The classification section 3 is divided into an upper classification section equipped with a spacer 21 and a vibration plate 22, and a lower classification section equipped with an aperture plate 18 and a suction housing 20. The mesh frame 6 to which the mesh 5 is fixed is placed loosely on the hand 7, and the vibration plate 22 in the upper classification section and the aperture plate 18 in the lower classification section are positioned approximately opposite the mesh 5. The lower classification section can be raised and lowered by a lifting mechanism 14. During classification, the lower classification section is raised, and the aperture plate 18 lifts the mesh 5 and mesh frame 6 and presses them against the upper classification section. At this time, the vibration plate 22 and spacer 21 in the upper classification section and the mask 19 formed on the aperture plate 18 in the lower classification section form a flow path through which air containing powder flows from the supply section 2, through the mesh 5 and aperture plate 18, toward the fine powder recovery section 4.

[0020] Vibrating plate 22 is fixed to the top of classifying section 3 by vibrating plate fixing frame 23 and support columns 24. Vibrator 25, which is a vibration mechanism, is fixed to the top of vibrating plate 22. Spacer 21 is fixed to the bottom of vibrating plate 22. A pipe through which powder is supplied from supply section 2 is connected to vibrating plate fixing frame 23, and the powder is transported to the bottom of vibrating plate 22 through this pipe and two supply ports formed in vibrating plate 22.

[0021] It is desirable to use a vibrator using piezoelectric ceramics as the vibrator 25, and in particular a Langevin vibrator to obtain stronger vibrations. It is desirable to use a hard material such as metal for the diaphragm 22 in order to suppress energy attenuation of such an ultrasonic vibrator. If metal should not be mixed into the powder, it is desirable to apply a fluororesin coating, PEEK coating, or DLC coating to the surface of the diaphragm 22. Furthermore, if aluminum is used for the diaphragm 22, it is desirable to apply an anodized aluminum treatment or the like.

[0022] FIG. 4 is a top view showing an example of the opening shape of the spacer 21. The spacer 21 is a plate of uniform thickness with an opening provided inside. As described above, the vibration plate 22 has two powder supply ports, one on the left and one on the right in FIG. 3, and the spacer 21 has a substantially rectangular opening in the left-right direction to form a flow path for the powder supplied from the two supply ports. This opening forms a space (powder introduction flow path) between the vibration plate 22 and the mesh 5 through which the powder flows when the mesh 5 is pressed against the top of the classifier. (In the examples shown in FIGS. 3 and 4, the powder flows left and right from each supply port.) The spacer 21 can be made of a material such as metal, plastic, or rubber. If metal is not to be mixed into the powder, it is preferable to use plastic or rubber as the material for the spacer 21. Furthermore, to increase the airtightness of the space, it is preferable to use an elastic material such as rubber as the material for the spacer 21.

[0023] The mesh 5 is composed of a classification mesh 26 and an aperture plate 27. The classification mesh 26 is made of wires woven into a mesh pattern, and the mesh size (roughness) of each mesh is equal to or smaller than the lower limit of the size of the foreign particles to be removed and larger than the median particle size of the powder to be collected. If the mesh size of the classification mesh 26 is slightly larger than the size of the foreign particles, the classification mesh 26 can substantially remove the foreign particles and improve throughput. However, if the mesh size is smaller than the lower limit of the size of the foreign particles, the classification mesh 26 can reliably remove the foreign particles and the reliability of the classifier 1 is improved. If metal foreign particles originating from the mesh need not be mixed into the powder, it is desirable to use a resin mesh for the classification mesh 26, using nylon or other wire material as the wire material.

[0024] The aperture plate 27 flattens the classification mesh 26 during suction by the suction mechanism of the fine powder collection section 4. It is a plate with higher rigidity than the classification mesh 26 and is provided with multiple apertures extending vertically to allow powder to pass through. When targeting powders with an average particle size of several microns to several tens of microns, such as electrode materials for lithium-ion batteries, classification meshes 26 with openings of 100 μm or less are often used. However, such meshes are weak, and suction can cause the mesh to deform, changing the shape of the mesh openings and preventing the expected classification performance. Furthermore, excessive deformation can even cause the mesh to tear. Therefore, the mesh 5 is configured with a highly rigid aperture plate 27 to suppress deformation of the classification mesh 26. The aperture plate 27 can be made of a metal or plastic plate with holes drilled, a punched metal, or a mesh made of wires with a larger diameter than those used in the classification mesh 26. If it is desired to prevent metallic foreign matter from being mixed into the powder, a plastic plate, a mesh made of resin such as nylon, a metal plate coated with a non-metallic layer such as a resin coating such as fluororesin or a DLC coating, an anodized aluminum plate, or the like can be used as the aperture plate 27. When a mesh is used as the aperture plate 27, the aperture plate 27 acts as a reinforcing mesh for the classification mesh 26.

[0025] The aperture plate 18 is fixed to the base 15 via an aperture plate fixing frame 17 and support columns 16, and can be raised and lowered by the lifting mechanism 14. Like the aperture plate 27, the aperture plate 18 suppresses deformation of the mesh 5 during suction by the suction mechanism of the fine powder collection unit 4, and also fixes the suction housing 20. The aperture plate 18 is a highly rigid plate with multiple openings extending vertically through it to allow the powder to pass through. The aperture plate 18 may be made of a metal or plastic plate with holes drilled therein, a punched metal plate, or the like. To prevent metallic foreign matter from being mixed into the powder, the aperture plate 18 may be made of a plastic plate, a metal plate coated with a non-metallic layer such as a fluororesin or DLC coating, or an anodized aluminum plate.

[0026] The suction housing 20 forms a flow path for guiding the powder that has passed through the mesh 5 to the piping that connects to the fine powder collection section 4. The suction housing 20 is a rectangular or cylindrical member with the piping connected to the bottom, and is fixed to the opening plate 18. The suction housing 20 is made of a hard material, such as metal or plastic, that does not deform due to the negative pressure caused by suction. If it is necessary to prevent metallic foreign matter from being mixed into the powder, the suction housing 20 can be made of plastic or metal coated with a non-metallic layer, such as a resin coating such as fluororesin or a DLC coating. While this embodiment describes an example in which the suction housing 20 is fixed to the opening plate 18, the suction housing 20 may also be fixed to the base 15 via a support or the like. In this case, the upper part of the suction housing 20 abuts against the opening plate 18.

[0027] The mask 19 is placed above the aperture plate 18 to prevent powder from entering areas other than the openings of the suction housing 20. The mask 19 is, for example, a thin film or tape with openings of the same size as the openings of the suction housing 20. While the present embodiment describes an example in which the mask 19 is placed above the aperture plate 18, the mask 19 may also be placed below the aperture plate 18. Furthermore, if the aperture plate 18 has openings only in areas corresponding to the openings of the suction housing 20, the mask 19 is not necessary. Furthermore, another mask with openings similar to the mask 19 may be placed above the mesh 5. Placing a mask on the mesh 5 can prevent powder from entering the openings of the mesh 5 corresponding to the non-opening areas of the suction housing 20. This reduces the amount of powder that enters the mesh 5 and is not classified, thereby improving yield.

[0028] The operation of the classifier 3 having the above configuration will be described. First, the lifting mechanism 14 raises the base 15, causing the apertured plate 18 fixed to the base 15 to rise and come into contact with the apertured plate 27 of the mesh 5 via the mask 19. When the apertured plate 18 further rises in this state, the mesh 5 and mesh frame 6, which are placed on the hand 7, are also lifted by the apertured plate 18 and rise. The lifting mechanism 14 further raises the apertured plate 18, mesh 5, and mesh frame 6 in the above state and stops when the classification mesh 26 of the mesh 5 comes into contact with the spacer 21. At this time, the classifier 3 is in a state where the classification mesh 26 of the mesh 5 comes into contact with the spacer 21, and the apertured plate 18 comes into contact with the apertured plate 27 via the mask 19. In this state, as described above, the spacer 21 forms a space between the vibration plate 22 and the mesh 5, and powder is supplied to this space from the supply unit 2 through a pipe at a predetermined rate. Also, the vibrator 25 operates to vibrate the vibration plate 22, and the suction mechanism of the fine powder recovery section 4 starts suction.

[0029] When the space is filled with powder, the vibration of the vibrating plate 22 propagates to the powder in the space, generating shear forces, particularly in the powder in contact with the mesh 5. This shear force shears the powder in contact with the mesh 5, breaking down agglomerates and loosening adhesions between particles, fluidizing them and making them more likely to pass through the mesh 5. Because the powder in the space is being sucked toward the mesh 5 by the suction mechanism of the fine powder collection unit 4, the fluidized powder passes through the mesh 5, except for coarse particles that cannot pass through the classification mesh 26. Powder in other spaces also comes into contact with the mesh 5 one after another due to the suction force toward the mesh 5, becoming sheared and fluidized as described above and passing through the mesh 5. In this way, the powder in contact with the mesh 5 becomes fluidized and passes through the mesh 5 one after another, thereby increasing the amount and speed of powder passing through and improving throughput. The powder that passes through the mesh 5 passes through the openings in the mask 19, passes through the opening plate 18, enters the suction housing 20, and is sucked into a pipe connected to its bottom and collected in the fine powder collection unit 4. On the other hand, coarse particles that cannot pass through the mesh 5 remain on the mesh 5 .

[0030] The classifying unit 3 stops the above operation after, for example, a predetermined time has elapsed. Then, the lifting mechanism 14 lowers the base 15, and the aperture plate 18 returns to the position shown in Figure 3. The mesh 5 and mesh frame 6 are again placed on the hand 7, and are moved to the cleaning unit 9 by the linear motion mechanism 8 with the coarse particles remaining on the mesh 5.

[0031] As described above, in order to transmit the vibration of the vibration plate 22 to the powder filled in the space and to generate a shear force in the powder in contact with the mesh 5 to shear the powder, it is necessary to strictly define the distance between the vibration plate 22 that forms the space and the mesh 5. In other words, this distance must be set to a distance that is equal to or less than the distance at which the powder in contact with the mesh 5 can be sheared and pass through the mesh 5 without clogging the mesh 5. Since this distance depends on the material and particle size distribution of the powder, the thickness of the spacer 21 that forms the distance between the vibration plate 22 and the mesh 5 is adjusted depending on the powder used. As an example, an NMC-based material powder (LiNi 0.5 Mn 0.3 Co 0.2 Table 1 below shows the results of evaluating the throughput of the classification section by changing the spacer thickness (spacer thickness).

[0032] [Table 1]

[0033] In this example, we evaluated the throughput of the classifier using a 32 μm mesh and spacers with thicknesses ranging from 0.3 mm to 2.0 mm. Specifically, the NMC-based material powder was fed into the classifier at a constant rate, and after 25 seconds of classification, we evaluated whether the mesh clogged and the suction force changed. In Table 1, the evaluation results are indicated by a circle (○) if the mesh did not clog, and by an × (×) if the mesh clogged and the suction force decreased. When the spacer thickness was 2.0 mm, the mesh clogged even at a powder feed rate of 1.7 g / sec. However, when the spacer thickness was reduced to 1.0 mm or 0.5 mm, no clogging occurred, even at a powder feed rate of 2.0 g / sec. Therefore, in this example, by reducing the spacer thickness to less than 2 mm, the powder was sheared by the propagation of vibration, resulting in high throughput. In this example, when the spacer thickness was set to 0.3 mm, the pressure loss in the flow path between the vibration plate 22 and the mesh 5 increased, and sufficient suction force could not be obtained. However, to address this, the pressure loss can be reduced and the suction force improved by widening the flow path width in the surface direction of the vibration plate 22 or shortening the flow path length.

[0034] Next, the cleaning unit 9 will be described with reference to Fig. 5. Fig. 5 is a cross-sectional view showing an example of the detailed configuration of the cleaning unit 9. The cleaning unit 9 includes a lifting mechanism 28, a cover 29, a clogging powder removal mechanism 30, an opening plate 31, a suction housing 32, and a support 33.

[0035] The cleaning section 9 is divided into an upper cleaning section equipped with a suction housing 32 and a lower cleaning section equipped with a cover 29. The mesh frame 6 to which the mesh 5 is fixed is moved from the classifying section 3 to the cleaning section 9 by a linear motion mechanism 8 (not shown) while being placed loose on the hand 7. The lower cleaning section can be raised and lowered by a lifting mechanism 28, and during cleaning, the lower cleaning section is raised, and the mesh 5 and mesh frame 6 are lifted by the cover 29 and pressed against the upper cleaning section. At this time, the cover 29 and the suction housing 32 form a flow path through which air flows from below the mesh 5 toward the coarse particle collection section 10, and this airflow collects the coarse particles remaining on the mesh 5 after classification into the coarse particle collection section 10.

[0036] The suction housing 32 forms a flow path for guiding the coarse particles remaining on the mesh 5 after classification to a pipe connected to the coarse particle recovery unit 10. The suction housing 32 is a rectangular or cylindrical member with the pipe connected to the top, and is fixed to the top of the cleaning unit 9 by supports 33. The suction housing 32 is made of a hard material such as metal or plastic that will not deform due to the negative pressure caused by suction. If it is necessary to prevent metallic foreign matter from being mixed into the powder, plastic or metal coated with a non-metallic layer such as a resin coating such as fluororesin or DLC coating is used.

[0037] An aperture plate 31 is installed at the opening of the suction housing 32. The aperture plate 31 reduces deformation of the mesh 5 during suction by the suction mechanism of the coarse-particle recovery unit 10. It is a highly rigid plate with multiple vertically penetrating apertures for allowing the powder to pass through. The aperture plate 31 can be made of a metal or plastic plate with holes, punched metal, mesh, or the like. To prevent the inclusion of metallic foreign matter in the powder, the aperture plate 31 can be made of a plastic plate, a resin mesh such as nylon, a metal plate coated with a non-metallic layer such as a fluororesin or DLC coating, or an anodized aluminum plate. It is desirable for the aperture plate 31 to deform slightly during suction, but not to the extent that irreversible deformation or tearing of the classification mesh 26 occurs. As the aperture plate 31 deforms, the classification mesh 26 also deforms accordingly, making it easier for coarse particles trapped in the apertures of the classification mesh 26 to escape.

[0038] The cover 29 is intended to prevent powder adhering to the mesh 5 from scattering inside the device during cleaning. The cover 29 is a rectangular or cylindrical member with an opening on one side thereof that is connected to the outside air, and when the suction mechanism of the coarse powder recovery unit 10 is using it to suck in outside air, it creates an air current that flows from below the mesh 5 to above it.

[0039] A clogging powder removal mechanism 30 is provided inside the cover 29. The clogging powder removal mechanism 30 blows out clogging powder by applying a strong air current to the underside of the mesh 5. As the clogging powder removal mechanism 30, for example, a pulse air gun or the like is used.

[0040] The operation of the cleaning unit 9 having the above configuration will be described. First, the lifting mechanism 28 lifts the cover 29, causing the upper part of the cover 29 to abut against the aperture plate 27 of the mesh 5. When the cover 29 is further lifted in this state, the mesh 5 and mesh frame 6 are lifted by the cover 29 and also rise, since they are placed on the hand 7. The lifting mechanism 28 further lifts the cover 29, mesh 5, and mesh frame 6 in the above state, and stops when the classification mesh 26 of the mesh 5 abuts against the aperture plate 31. At this time, the cleaning unit 9 is in a state in which the classification mesh 26 of the mesh 5 abuts against the aperture plate 31, and the cover 29 abuts against the aperture plate 27.

[0041] In this state, when the suction mechanism of the coarse powder recovery section 10 starts suction, as described above, the opening plate 31 and the classification mesh 26 are slightly deformed, causing the coarse powder caught in the openings of the classification mesh 26 to be released and sucked up into the suction housing 32. In addition, by applying a strong airflow from the opening plate 27 side by the clogging powder removal mechanism 30, the clogging powder is blown out from the classification mesh 26 and sucked up into the suction housing 32. The coarse powder etc. sucked up into the suction housing 32 is sucked into the piping connected to the top thereof and recovered in the coarse powder recovery section 10.

[0042] The cleaning unit 9 stops the above operation, for example, after a predetermined time has elapsed. Then, the lifting mechanism 28 lowers the cover 29, and the cover 29 returns to the position shown in Figure 5. The mesh 5 and mesh frame 6 are again placed on the hand 7, and are moved to the classifying unit 3 by the linear motion mechanism 8.

[0043] As described above, according to the first embodiment, the vibration of the vibrating plate 22 is transmitted to the powder, shearing the powder in contact with the mesh 5, and loosening the agglomeration of the powder and adhesion between particles of powder. In this way, the powder can be fluidized, thereby improving the throughput of classification.

[0044] In this embodiment, the vibrating plate 22 is vibrated by the vibrator 25, but for example, a vibrating mechanism such as a vibrator or a vibrator may be attached to the mesh frame 6, etc., to vibrate the mesh 5 instead of or together with the vibrating plate 22.

[0045] In addition, in this embodiment, an example has been described in which the suction mechanism of the fine powder recovery section 4 and the coarse powder recovery section 10 is used as the airflow generating mechanism for transporting the powder, but instead of the suction mechanism, high-pressure gas may be connected to the supply section 2 and used as the source of the airflow.

[0046] In addition, in this embodiment, an example has been described in which two supply ports are provided on the vibration plate 22 and powder is supplied from two directions, but it is also possible to have one supply port and supply from one direction, or three or more supply ports and supply from three or more directions.

[0047] Furthermore, in this embodiment, an example has been described in which the classifying unit 3 and the cleaning unit 9 are each provided with an elevating mechanism, but they may be simultaneously elevated and lowered by a single elevating mechanism.

[0048] Furthermore, in this embodiment, an example in which the spacer 21 is fixed to the diaphragm 22 has been described, but the diaphragm and the spacer may be integrally formed.

[0049] In addition, in this embodiment, an example has been shown in which a pulse air gun or the like is installed inside the cover 29 as the clogging powder removal mechanism 30 of the cleaning unit 9, but a vibrator may be installed in the cover 29 to vibrate the mesh 5.

[0050] In the classifier 3 in Example 1 described above, a supply port is formed in the diaphragm 22, and powder is supplied from this supply port to the underside of the diaphragm 22. However, a supply port does not necessarily need to be formed in the diaphragm 22, and powder can be supplied in a different manner. A modified example of such a classifier will be described with reference to FIGS. 6 and 7. FIG. 6 is a cross-sectional view showing an example of the detailed configuration of the classifier 35 in the modified example. As will be described in detail below, this modified example is configured such that an opening is formed in the diaphragm, and powder is supplied from above the diaphragm. Note that in FIG. 6, the same components as those in the classifier 3 shown in FIG. 3 are denoted by the same reference numerals, and the following description will omit the same content as in the classifier 3. Furthermore, the configuration of the classifier in this modified example is the same as that of the classifier 1 shown in FIG. 1, except for the classifier 3, and therefore will not be described again. The upper part of the classifier 35 includes a spacer 40, a diaphragm 41, a supply housing 45, a diaphragm fixing frame 23, a support 24, and a vibrator 25.

[0051] The vibration plate 41 is fixed to the top of the classification section 35 by the vibration plate fixing frame 23 and the support columns 24. The vibrator 25 and supply housing 45 are fixed to the top of the vibration plate 41. The supply housing 45 is a rectangular or cylindrical member with a pipe connected to the top of the supply housing 45 for supplying powder. The powder is supplied from above the vibration plate 41 through this pipe into the supply housing. The vibration plate 41 has multiple openings that penetrate vertically to allow the powder to pass through. To minimize energy attenuation of the ultrasonic vibrator, the vibration plate 41 is preferably made of a hard material such as metal with holes drilled or punched metal. If metal is not to be mixed into the powder, it is preferable to coat the surface of the vibration plate 41 with a fluororesin coating, a PEEK coating, or DLC coating. If aluminum is used for the vibration plate 41, it is preferable to anodize it.

[0052] FIG. 7 is a top view showing an example of the shape of the opening of the spacer 40. The spacer 40 is a plate of uniform thickness with an opening provided on the inside thereof, and this opening forms a space between the vibration plate 41 and the mesh 5 through which the powder flows when the mesh 5 is pressed against the classification section. The spacer 40 can be made of a material such as metal, plastic, or rubber. If metal should not be mixed into the powder, it is preferable to use plastic or rubber. Furthermore, to increase the airtightness of the space, it is preferable to use an elastic material such as rubber as the material of the spacer 40.

[0053] The operation of the classification unit 35 in this modification differs from that of the classification unit 3 in Example 1 as follows. Similar to the classification unit 3, when the mesh 5 rises and the classification mesh 26 abuts against the spacer 40, and the aperture plate 18 abuts against the aperture plate 27 without a mask, the spacer 40 forms a space between the vibration plate 41 and the mesh 5. In this state, powder is supplied from the supply unit 2 at a predetermined rate from above the vibration plate 41 through a pipe connected to the top of the supply housing 45. The supplied powder passes through multiple openings in the vibration plate 41 and enters the space. Similar to the classification unit 3, when the space is filled with powder, the vibration of the vibration plate 41 propagates to the powder in the space, and the powder in contact with the mesh 5 is sheared and fluidized. All of the powder passes through the mesh 5, except for coarse powder that cannot pass through the classification mesh 26.

[0054] In this modification, the openings of the spacer 40 are provided so as to roughly correspond to the areas of the openings of the suction housing 20. This makes it possible to prevent powder from entering the openings of the mesh 5 that correspond to the non-opening areas of the suction housing 20, thereby achieving the same effect as the mask 19 in the classification unit 3. As with the spacer 21 in the classification unit 3, the thickness of the spacer 40 (spacer thickness) is set so that the distance between the vibration plate 41 and the mesh 5 is equal to or less than the distance at which powder in contact with the mesh 5 can be sheared and pass through the mesh 5 without clogging the mesh 5.

[0055] By configuring the classifying section 35 as described above, the present modification also achieves a throughput equivalent to that of the classifying section 3 in the first embodiment. [Example]

[0056] In the classifying unit 3 in Example 1, the vibration plate 22 is installed above the classifying unit and the suction housing 20 is installed below the classifying unit, but this configuration can be reversed. Similarly, in the cleaning unit 9 in Example 1, the suction housing 32 is installed above the cleaning unit and the cover 29 is installed below the cleaning unit, but this configuration can be reversed. Example 2 will be described with reference to FIGS. 8 to 11. FIG. 8 is a top view showing an example of the schematic configuration of a classifying device in Example 2. In FIG. 8, the same components as those in the classifying device 1 shown in FIG. 1 are designated by the same reference numerals, and the following description will omit description of content that overlaps with that of the classifying device 1. The classifying device 46 includes a supply unit 2, a classifying unit 47, a fine powder collecting unit 4, a mesh 55, a mesh frame 6, a hand 7, a linear motion mechanism 8, a cleaning unit 48, a coarse powder collecting unit 10, piping 49, an air intake 51, and valves 50, 52, 53, and 54. The classification device 1 differs from the classification device 1 of the first embodiment in the configuration of the classification section 47 and cleaning section 48, and in that a pipe 49, an intake port 51, and valves 50, 52, 53, and 54 are added.

[0057] The classification unit 47 and mesh 55 will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view showing an example of the detailed configuration of the classification unit 47 and mesh 55. The classification unit 47 includes a lifting mechanism 56, a base 57, support posts 58, a vibration plate fixing frame 62, a vibration plate 59, a vibrator 60, a spacer 61, an aperture plate 64, a mask 65, an aperture plate fixing frame 66, support posts 67, and a suction housing 68.

[0058] The classification section 47 is divided into an upper section equipped with an aperture plate 64 and a suction housing 68, and a lower section equipped with a spacer 61 and a vibration plate 59. The mesh frame 6 to which the mesh 55 is fixed is placed loosely on the hand 7. The lower section can be raised and lowered by a lifting mechanism 56. During classification, the lower section is raised, and the mesh 55 and mesh frame 6 are lifted by the spacer 61 and pressed against the upper section. At this time, the vibration plate 59 and spacer 61 at the lower section of the classification section and the mask 65 formed below the aperture plate 64 at the upper section of the classification section form a flow path through which air containing powder flows from the supply section 2, through the mesh 55 and aperture plate 64, and toward the fine powder recovery section 4.

[0059] Vibration plate 59 is fixed to base 57 via vibration plate fixing frame 62 and support columns 58, and can be raised and lowered by lifting mechanism 56. Vibrator 60 is fixed to the lower part of vibration plate 59. Spacer 61 is fixed to the upper part of vibration plate 59. A pipe through which powder is supplied from supply unit 2 is connected to vibration plate fixing frame 62, and the powder is transported to the upper side of vibration plate 59 through this pipe and two supply ports formed in vibration plate 59. In addition to the powder supply ports formed in two places, on the left and right sides in FIG. 9, vibration plate 59 also has an opening (intake port) on the rear (rear) side in FIG. 9 that connects to intake port 51 shown in FIG. 8, and an opening (recovery opening) on ​​the front (near) side in FIG. 9 that connects to pipe 49 shown in FIG. 8.

[0060] A vibrator using piezoelectric ceramics is used for the vibrator 60. To obtain stronger vibrations, it is preferable to use a Langevin type vibrator. To suppress the energy attenuation of such an ultrasonic vibrator, it is preferable to use a hard material such as metal for the diaphragm 59. If metal should not be mixed into the powder, it is preferable to apply a fluororesin coating, PEEK coating, or DLC coating to the surface of the diaphragm 59. Furthermore, if aluminum is used for the diaphragm 59, it is preferable to apply an anodizing treatment or the like.

[0061] FIG. 10 is a top view showing an example of the shape of the opening of the spacer 61. The spacer 61 is a plate of uniform thickness with openings provided inside. As described above, the vibration plate 59 is provided with two powder supply ports, one on the left and one on the right in FIG. 9, and the spacer 61 is provided with approximately rectangular openings in the left-right direction in FIG. 10 to form a flow path (first flow path) for the powder supplied from the two supply ports. These openings form a space between the vibration plate 59 and the mesh 55 through which the powder flows when the spacer 61 is in contact with the mesh 55 (in the example shown in FIGS. 9 and 10, the powder flows in the left-right direction from each supply port). Furthermore, as described above, the vibration plate 59 is provided with recovery openings and intake openings (not shown) at the front and back in FIG. 9, and the spacer 61 is also provided with approximately rectangular openings in the up-down direction perpendicular to the left-right openings in FIG. 10 to form a flow path (second flow path) for the airflow generated by the two openings.

[0062] The spacer 61 is made of a material such as metal, plastic, or rubber. If metal should not be mixed into the powder, it is desirable to use plastic or rubber as the material for the spacer 61. Furthermore, in order to increase the airtightness of the space, it is desirable to use an elastic material such as rubber as the material for the spacer 61. As with the spacer 21 in the classifying section 3, the thickness of the spacer 61 (spacer thickness) is set so that the distance between the vibration plate 59 and the mesh 55 is equal to or less than the distance at which the powder in contact with the mesh 5 can be sheared and pass through the mesh 5 without clogging the mesh 5.

[0063] The mesh 55 is composed of a classification mesh 26 and an aperture plate 27. In the mesh 5 in Example 1, the classification mesh 26 is arranged above the aperture plate 27, but the mesh 55 in Example 2 is different in that the classification mesh 26 is arranged below the aperture plate 27. Except for this point, the configurations of the classification mesh 26 and the aperture plate 27 are the same as those of the mesh 5 in Example 1, so a description thereof will be omitted.

[0064] The aperture plate 64 is fixed to the top of the classifier 47 by an aperture plate fixing frame 66 and supports 67. The aperture plate 64 suppresses deformation of the mesh 55 when suction is performed by the suction mechanism of the fine powder recovery unit 4, and also fixes the suction housing 68. The aperture plate 64 is a highly rigid plate with multiple openings that penetrate vertically to allow the powder to pass through. The aperture plate 64 can be made of a metal or plastic plate with holes drilled into it, or a punched metal. If it is desired to prevent metallic foreign matter from being mixed into the powder, the aperture plate 64 can be made of a plastic plate, a metal plate coated with a resin such as a fluororesin or a non-metallic layer such as a DLC coating, or an anodized aluminum plate.

[0065] The suction housing 68 is used to form a flow path for guiding the powder that has passed through the mesh 55 to the piping that connects to the fine powder recovery section 4. The suction housing 68 is a rectangular or cylindrical member with the piping connected to the top, and is fixed to the opening plate 64. The suction housing 68 is made of a hard material such as metal or plastic that will not deform due to the negative pressure caused by suction. If it is necessary to prevent metallic foreign matter from being mixed into the powder, the suction housing 68 should be made of plastic or metal coated with a non-metallic layer such as a resin coating such as fluororesin or DLC coating.

[0066] The mask 65 is placed below the aperture plate 64 to prevent powder from entering areas other than the openings of the suction housing 68. The mask 65 is, for example, a thin film or tape with openings of the same size as the openings of the suction housing 68. While this embodiment describes an example in which the mask 65 is placed below the aperture plate 64, if the aperture plate 64 has openings only in the areas corresponding to the openings of the suction housing 68, the mask 65 is not necessary. Alternatively, another mask with openings similar to the mask 65 may be placed below the mesh 55. Placing a mask below the mesh 55 can prevent powder from entering the openings of the mesh 55 corresponding to the non-opening areas of the suction housing 68. This reduces the amount of powder that enters the mesh 55 and is not classified, thereby improving yield.

[0067] The operation of the classifier 46 and classifier unit 47 having the above configuration will be described. First, during classification, valves 50 and 52 in the classifier 46 are closed and valves 53 and 54 are open. When the lifting mechanism 56 raises the base 57, the vibration plate 59 fixed to the base 57 rises, and the spacer 61 abuts against the classification mesh 26 of the mesh 55. When the vibration plate 59 rises further in this state, since the mesh 55 and mesh frame 6 are placed on the hand 7, the mesh 55 and mesh frame 6 are also raised by being lifted by the vibration plate 59. In the above state, the lifting mechanism 56 further raises the vibration plate 59, mesh 55, and mesh frame 6, and stops when the aperture plate 27 of the mesh 55 abuts against the aperture plate 64 via the mask 65. At this time, in the classifying section 47, the classification mesh 26 of the mesh 55 abuts against the spacer 61, and the aperture plate 64 abuts against the aperture plate 27 via the mask 65, and as described above, a space is formed between the vibration plate 59 and the mesh 55 by the spacer 61. In this state, powder is supplied to the space at a predetermined rate through the piping from the supply section 2. In addition, the vibrator 60 operates to vibrate the vibration plate 59, and the suction mechanism of the fine powder collection section 4 starts suction.

[0068] When the space is filled with powder, the vibration of the vibrating plate 59 propagates to the powder in the space, generating shear forces, particularly in the powder in contact with the mesh 55. This shear force shears the powder in contact with the mesh 55, breaking down agglomerates and loosening adhesions between particles, fluidizing them, and allowing them to pass through the mesh 55 more easily. Because the powder in the space is being sucked toward the mesh 55 by the suction mechanism of the fine powder collection unit 4, the fluidized powder passes through the mesh 55, except for coarse particles that cannot pass through the classification mesh 26. The other powder particles in the space also come into contact with the mesh 55 one after another due to the suction force toward the mesh 55, becoming sheared and fluidized as described above and passing through the mesh 55. As the powder in contact with the mesh 55 fluidizes and passes through the mesh 55 one after another, the amount and speed of the powder passing through the mesh 55 increase, improving throughput. The powder that passes through the mesh 55 passes through the openings in the mask 65, passes through the aperture plate 64, enters the suction housing 68, and is sucked into a pipe connected to its top and collected in the fine powder collection unit 4. On the other hand, the coarse particles that cannot pass through the mesh 55 remain on the vibration plate 59 .

[0069] After a predetermined time has elapsed since the start of classification, for example, the classifier 47 is left in its original state, but the valves 50 and 52 in the classifier 46 are opened and the valves 53 and 54 are closed, and the suction mechanism of the coarse particle recovery unit 10 begins suction. This generates an airflow that runs from the intake port 51 through the second flow path formed by the front and rear openings in the vibrating plate 59 and the front and rear openings in the spacer 61 to the piping 49, and this airflow transports the coarse particles that do not pass through the mesh 55 and remain on the vibrating plate 59 via the piping 49 to the coarse particle recovery unit 10. In this way, the open / closed states of the valves 50 and 52 and the valves 53 and 54 are switched to alternate between classification and coarse particle recovery, thereby further improving the efficiency of classification.

[0070] Note that, for example, when classification and coarse particle collection have been performed a predetermined number of times, or when a predetermined time has elapsed after repeating classification and coarse particle collection, the classifying unit 47 stops the above operation. Then, all valves are closed, and the lifting mechanism 56 lowers the base 57, returning the vibration plate 59 to the position shown in Figure 9. The mesh 5 and mesh frame 6 are again placed on the hand 7, and are moved to the cleaning unit 48 by the linear motion mechanism 8.

[0071] Next, the cleaning unit 48 will be described with reference to Fig. 11. Fig. 11 is a cross-sectional view showing an example of the detailed configuration of the cleaning unit 48 in Example 2. The cleaning unit 48 includes a lifting mechanism 69, a base 70, a support 71, a suction housing 72, an opening plate 73, a cover 74, and a clogging powder removal mechanism 75.

[0072] The cleaning section 48 is divided into an upper cleaning section equipped with a cover 74 and a lower cleaning section equipped with a suction housing 72. The mesh frame 6 to which the mesh 55 is fixed is moved from the classification section 47 to the cleaning section 48 by a linear motion mechanism 8 (not shown) while being placed loose on the hand 7. The lower cleaning section can be raised and lowered by a lifting mechanism 69, and during cleaning, the lower cleaning section is raised, and the mesh 55 and mesh frame 6 are lifted by the opening plate 73 and pressed against the upper cleaning section. At this time, the cover 74 and the suction housing 72 form a flow path through which air flows from above the mesh 55 toward the coarse particle collection section 10, and this airflow collects the coarse particles that have adhered to the mesh 55 after classification into the coarse particle collection section 10.

[0073] The suction housing 72 is used to form a flow path for guiding the powder adhering to the mesh 55 after classification to a pipe connected to the coarse powder recovery section 10. The suction housing 72 is a rectangular or cylindrical member with the above-mentioned pipe connected to the bottom, fixed to a base 70 by supports 71, and can be raised and lowered by a lifting mechanism 69. The suction housing 72 is made of a hard material such as metal or plastic that will not deform due to the negative pressure caused by suction. If it is necessary to prevent metallic foreign matter from being mixed into the powder, plastic or metal coated with a non-metallic layer such as a resin coating such as fluororesin or DLC coating is used.

[0074] An aperture plate 73 is installed at the opening of the suction housing 72. The aperture plate 73 reduces deformation of the mesh 55 during suction by the suction mechanism of the coarse-particle recovery unit 10. It is a highly rigid plate with multiple vertically extending apertures for allowing the powder to pass through. The aperture plate 73 can be made of a metal or plastic plate with holes, punched metal, mesh, or the like. To prevent the inclusion of metallic foreign matter in the powder, the aperture plate 73 can be made of a plastic plate, a mesh made of resin such as nylon, a metal plate coated with a non-metallic layer such as a fluororesin or DLC coating, or an anodized aluminum plate. It is desirable for the aperture plate 73 to deform slightly during suction, so as not to cause irreversible deformation or tearing of the classification mesh 26. As the aperture plate 73 deforms, the classification mesh 26 also deforms accordingly, making it easier for coarse particles trapped in the apertures of the classification mesh 26 to escape.

[0075] The cover 74 is intended to prevent powder adhering to the mesh 55 from scattering inside the device during cleaning. The cover 74 is a rectangular or cylindrical member with an opening on one side thereof that is connected to the outside air, and when the suction mechanism of the coarse powder recovery unit 10 is used for suction, the outside air is sucked in through the opening, creating an air current that flows from above to below the mesh 55.

[0076] A clogging powder removal mechanism 75 is provided inside the cover 74. The clogging powder removal mechanism 75 blows out clogging powder by applying a strong air current from above the mesh 55. As the clogging powder removal mechanism 75, for example, a pulse air gun or the like is used.

[0077] The operation of the cleaning unit 48 having the above configuration will be described. When the mesh 5 and mesh frame 6 are moved by the linear motion mechanism 8, the lifting mechanism 69 raises the base 70, causing the suction housing 72 fixed to the base 70 and the aperture plate 73 attached thereto to rise, and the top of the aperture plate 73 abuts against the classification mesh 26 of the mesh 55. If the aperture plate 73 rises further in this state, the mesh 55 and mesh frame 6, which are placed on the hand 7, are also lifted by the aperture plate 73 and rise. The lifting mechanism 69 further raises the aperture plate 73, mesh 55, and mesh frame 6 in the above state, and stops when the aperture plate 27 of the mesh 55 abuts against the cover 74. At this time, the cleaning unit 48 is in a state in which the classification mesh 26 of the mesh 55 abuts against the aperture plate 73, and the cover 74 abuts against the aperture plate 27.

[0078] In this state, when the suction mechanism of the coarse powder recovery section 10 starts suction, as described above, the opening plate 73 and the classification mesh 26 are slightly deformed, causing the coarse powder caught in the openings of the classification mesh 26 to escape and be sucked into the suction housing 72. In addition, by applying a strong airflow from the opening plate 27 side by the clogging powder removal mechanism 75, the clogging powder is blown out from the classification mesh 26 and sucked into the suction housing 32. The coarse powder and the like sucked into the suction housing 32 are sucked into the piping connected to the bottom thereof and collected in the coarse powder recovery section 10.

[0079] The cleaning unit 48 stops the above operation, for example, after a predetermined time has elapsed. Then, the lifting mechanism 69 lowers the base 70, and the suction housing 72 and the aperture plate 73 installed therein return to the positions shown in Figure 11. The mesh 55 and mesh frame 6 are again placed on the hand 7, and are moved to the classifying unit 47 by the linear motion mechanism 8.

[0080] As described above, according to Example 2, by arranging the vibration plate 59 on the lower side of the classifier 47, gravity increases the frictional resistance between the vibration plate 59 and the powder on it, allowing vibrations to be efficiently transmitted to the powder. Furthermore, coarse particles that cannot pass through the mesh 55 remain on the vibration plate 59, while the mesh 55 is located above it, making it less likely to become clogged with the remaining powder, thereby reducing clogging of the mesh 55. Due to these effects, the classifier 46 of Example 2 can further improve classification throughput compared to the classifier 1 of Example 1. In this example, the suction mechanisms of the fine powder collection unit 4 and the coarse powder collection unit 10 are used as sources of airflow to transport the powder. However, instead of the suction mechanism, high-pressure gas may be connected to the supply unit 2 and used as the source of the airflow.

[0081] In addition, in this embodiment, an example has been described in which two supply ports are installed on the vibration plate 59 and powder is supplied from two directions, but it is also possible to use one supply port and supply from one direction, or three or more supply ports and supply from three or more directions.

[0082] In addition, in this embodiment, an example has been described in which the classifying section 47 and the cleaning section 48 are each provided with an elevating mechanism, but they may be simultaneously elevated by a single elevating mechanism.

[0083] Furthermore, in this embodiment, an example has been described in which the spacer 61 is fixed to the diaphragm 59, but the diaphragm and the spacer may be integrally formed.

[0084] In addition, in this embodiment, an example has been shown in which a pulse air gun or the like is installed inside the cover 74 as the clogging powder removal mechanism 75 of the cleaning unit 48, but a vibrator may also be installed on the cover 74 to vibrate the mesh 55. [Example]

[0085] Example 3 will be described with reference to FIGS. 12 and 13. In this example, a classification device is provided with multiple classification units and cleaning units to improve throughput. FIG. 12 is a top view showing an example of the schematic configuration of a classification device in Example 3. FIG. 12A is a top view showing the configuration of the classification device from the supply unit to the classification unit and cleaning unit, and FIG. 12B is a top view showing the configuration of the classification device from the classification unit and cleaning unit to the fine powder recovery unit and coarse powder recovery unit. A classification device 90 in this example includes a supply unit 76 as a powder supply mechanism, a rotary table 79, multiple classification units 3, multiple cleaning units 9, a fine powder recovery unit 80, and a coarse powder recovery unit 81. Note that the configurations of the classification units 3, mesh 5, and cleaning unit 9 in this example are the same as those in Example 1 and are therefore designated by the same reference numerals. In the following description, overlapping content will be omitted.

[0086] Four pairs of meshes 5 and mesh frames 6 are arranged on the rotary table 79, each at a 90-degree angle. Four classifying units 3 or four cleaning units 9 are alternately arranged at the positions where each mesh 5 and mesh frame 6 is arranged. This allows the meshes 5 and mesh frames 6 to move from the classifying units 3 to the cleaning units 9 and from the cleaning units 9 to the classifying units 3 by rotating the rotary table 79 by 90 degrees.

[0087] 12A, a conveyor 78 is disposed below the supply unit 76, and multiple pipes are connected to the conveyor 78 to supply powder to each of the classifying units 3. The powder is evenly distributed and supplied from the supply unit 76 to positions on the conveyor 78 corresponding to the multiple pipes, carried to each pipe by the conveyor 78, and supplied to each of the classifying units 3 through each pipe.

[0088] 12B, fine powder that passes through the classification mesh 26 in each classifying unit 3 is sucked and collected in the fine powder collection unit 80 through the pipes connecting each classifying unit 3 to the fine powder collection unit 80. Coarse powder that does not pass through the classification mesh 26 in the classifying unit 3 is sucked and collected in the coarse powder collection unit 81 through the pipes connecting each cleaning unit 9 to the coarse powder collection unit 81. In the fine powder collection, in order to prevent a decrease in suction force due to pressure loss in the pipes, the pipes are branched near the fine powder collection unit 80 and connected to each classifying unit 3.

[0089] The supply unit 76 will be described with reference to FIG. 13. FIG. 13 is a cross-sectional view showing an example of the detailed configuration of the supply unit 76. The supply unit 76 supplies powder to each classifier 3 at a predetermined rate and includes a housing 87 provided with a hopper 82, a constant-volume feeder 83, a screw 85, and multiple discharge ports 86. The powder is stored in the hopper 82 and supplied to the housing 87 (to the right in FIG. 13) at a predetermined rate by the constant-volume feeder 83. The powder supplied to the housing 87 is gradually moved (to the left in FIG. 13) by a screw 85 fixed to a rotating shaft 84 and supplied to each discharge port 86. A predetermined gap is provided between the discharge ports 86 and the conveyor 78, and the powder is supplied from the discharge port 86 onto the conveyor 78 through this gap. The supply rate of the powder is adjusted by the opening width of the discharge port 86, the gap between the discharge port 86 and the conveyor 78, and the feed speed of the conveyor 78.

[0090] The operation of the classification device 90 having the above configuration will be described. First, two of the four sets of meshes 5 and mesh frames 6 arranged on the rotary table 79 are located at positions where four classifying units 3 are arranged, and the other two sets are located at positions where four cleaning units 9 are arranged. In this state, each classifying unit 3 operates in the same manner as in Example 1, thereby classifying the powder supplied to each classifying unit 3 from the supply unit 76 at a predetermined rate, and fine powder is collected in the fine powder collection unit 80. Meanwhile, each cleaning unit 9 also operates in the same manner as in Example 1, thereby collecting coarse powder remaining on the mesh 5 or caught in the openings of the mesh 5 in the coarse powder collection unit 81. After a predetermined time has elapsed since the start of operation, each classifying unit 3 and each cleaning unit 9 stops operating, and the rotary table 79 rotates, for example, 90 degrees to the right. As a result, the two sets of mesh 5 and mesh frames 6 that were previously positioned with four classifying units 3 each move to positions with four cleaning units 9 each, and similarly, the two sets of mesh 5 and mesh frames 6 that were previously positioned with four cleaning units 9 each move to positions with four classifying units 3 each, and in this state, each classifying unit 3 and each cleaning unit 9 operates for a predetermined time. In the classifying device 90, by repeating this operation at predetermined time intervals, powder is classified by a total of eight classifying units 3 almost without interruption except for the time required for the rotation of the turntable 79, thereby significantly improving throughput.

[0091] As described above, according to Example 3, by providing a plurality of classifying sections in the classification device and operating each classifying section almost without interruption to classify the powder, it is possible to significantly improve throughput.

[0092] In this embodiment, an example in which two sets of four classifying units 3 and two sets of four cleaning units 9 are installed has been described, but three sets of four classifying units 3 and one set of four cleaning units 9 may also be installed. This makes it possible to improve the throughput per unit area of ​​the device. However, in this case, since each mesh 5 is used for classification by three sets of classifying units 3 in succession, it is necessary to manage the operating time of each classifying unit 3 (for example, by dividing the above-mentioned predetermined time into three and operating each classifying unit 3) so that each mesh 5 does not become clogged even if classification is repeated three times.

[0093] In addition, in this embodiment, an example has been described in which four meshes 5 are rotated by 90 degrees using a rotating table 79 to move between the classification section 3 and the cleaning section 9, but multiple meshes 5 may also be moved alternately between multiple sets of classification sections 3 and cleaning sections 9 using means other than a rotating table (for example, by combining multiple linear motion mechanisms).

[0094] In addition, in this embodiment, the same classifying section and cleaning section as those in the first embodiment are used, but the classifying section or cleaning section in the first modification or the second embodiment may be used in combination as appropriate.

[0095] Although the above describes various embodiments and variations of the present invention, the present invention is not limited to the above-described exemplary embodiments and includes various variations. For example, the above-described exemplary embodiments have been described in detail to facilitate understanding of the present invention, and the present invention is not limited to those including all of the components described herein. Furthermore, it is possible to replace part of the components of one exemplary embodiment with the components of another exemplary embodiment. It is also possible to add the components of another exemplary embodiment to the components of one exemplary embodiment. Furthermore, it is also possible to add, delete, or replace part of the components of each exemplary embodiment with other components. Furthermore, some or all of the above-described components, functions, processing units, processing means, etc. may be implemented in hardware, for example, by designing them as integrated circuits. Furthermore, the control lines and information lines in the figures are only those considered necessary for explanation, and not necessarily all are shown. It is also possible to consider that almost all components are interconnected. [Explanation of symbols]

[0096] 1, 46, 90...classifier 2, 76...supply section 3, 35, 47...Classification department 4, 80...Fine powder collection section 5, 55...Mesh 6...Mesh frame 7...Hand 8...Linear motion mechanism 9, 48...Cleaning section 10, 81... Coarse powder recovery section 11, 82...Hopper 12, 83...Fixed volume feeder 13, 86...supply port 14, 28, 56, 69...Lifting mechanism 15, 57, 70...base 16, 24, 33, 58, 67, 71...posts 17, 66...Aperture plate fixing frame 18, 27, 31, 64, 73...Aperture plates 19, 65...Mask 20, 32, 68, 72...Suction housing 21, 40, 61...Spacers 22, 41, 59...diaphragm 23, 62...Vibration plate fixing frame 25, 60... vibrator 26...Classification mesh 29, 74...Cover 30, 75...Clogging powder removal mechanism 45...Supply housing 49...Plumbing 50, 52, 53, 54... Valves 78...Conveyor 79...Rotary table 85...Screw 87…Housing

Claims

1. a member positioned in a flow path of the powder sample; A classification mesh that separates the powder to be collected from the powder to be removed, A powder classifying device comprising: the member is located at a position substantially opposite the classification mesh with a space therebetween, The space is filled with the transferred powder, the vibration mechanism vibrates at least one of the member and the classification mesh, The interval between the member in the space and the classification mesh is: the vibration is transmitted to the powder filled in the space and the distance that the powder is sheared is shorter than the distance that the vibration is transmitted to the powder filled in the space and the powder is sheared, Powder classification equipment.

2. 2. The powder classifying apparatus according to claim 1, A powder classifying device characterized in that the distance between the classification mesh and the member is less than 2 mm.

3. 2. The powder classifying apparatus according to claim 1, a classifying unit including at least the member and the vibration mechanism; an airflow generating mechanism; a recovery unit that recovers the powder that has passed through the classification mesh, A powder classifying device characterized in that powder is introduced into the space by an air current, and the classified powder is transported to the recovery section by the air current.

4. 4. The powder classifying apparatus according to claim 3, a spacer is provided between the classification mesh and the member; A powder classifying device, characterized in that the spacer forms a powder introduction flow path in the space.

5. 4. The powder classifying apparatus according to claim 3, A filter for suppressing deformation of the classification mesh due to airflow is provided on the side of the classification mesh opposite to the side facing the member. A powder classifying device comprising a reinforcing mesh.

6. 2. The powder classifying apparatus according to claim 1, a coarse powder recovery section that recovers coarse powder that did not pass through the classification mesh; an airflow generating mechanism that generates an airflow that transports powder from the classification mesh to the coarse powder collecting section, A powder classifying device characterized in that the space is provided with a flow path for discharging powder that did not pass through the classification mesh.

7. 2. The powder classifying apparatus according to claim 1, a classifying unit including at least the member and the vibration mechanism; a cleaning unit that cleans the classification mesh, the classification mesh is detachable from the classification unit and the cleaning unit; A powder classifying device characterized in that powder adhering to the classification mesh after classification is removed in the cleaning section.

8. 4. The powder classifying apparatus according to claim 3, A plurality of the classifying units; a powder supply mechanism having a plurality of powder outlets; A powder classifying device, characterized in that powder is supplied to each of the classifying sections from each of the powder discharge ports.

9. 9. The powder classifying apparatus according to claim 8, A powder classifying device, characterized in that the plurality of classifying sections are connected to one of the airflow generating mechanisms.

10. A classification method for a powder classifier including at least a component positioned in a flow path of a powder sample, a classification mesh for classifying powder to be collected and powder to be removed, and a vibration mechanism, comprising: The member is brought into close proximity to the classification mesh so as to substantially face the classification mesh, forming a space between the member and the classification mesh; Filling the space with the powder, vibrating at least one of the member and the classification mesh by the vibration mechanism, thereby transmitting vibration to the powder; classifying the powder by shearing the powder and passing it through the classification mesh; In forming the space, the member is brought close to the powder filled in the space at a distance shorter than the distance at which vibration is transmitted to the powder and the powder is sheared. A classification method characterized by:

11. The classification method according to claim 10, The member is brought close to the classification mesh to a distance of less than 2 mm to form the space between the member and the classification mesh. A classification method characterized by:

12. The classification method according to claim 10, The powder classifying device further includes an airflow generating mechanism and a recovery unit that recovers the powder that has passed through the classification mesh, generating an airflow and introducing the powder into the space by the airflow; The classified powder is transported to the recovery section by the airflow. A classification method characterized by:

13. The classification method according to claim 12, a spacer is provided on the member; a powder introduction channel is formed in the space by the spacer; A classification method characterized by:

14. The classification method according to claim 10, The powder classifying device further includes an airflow generating mechanism and a coarse powder recovery unit that recovers coarse powder that did not pass through the classification mesh, an airflow is generated, and the coarse particles that did not pass through the classification mesh are transported from the space to the coarse particle recovery section by the airflow; A classification method characterized by:

15. The classification method according to claim 10, the powder classifying device further includes a cleaning unit that cleans the classification mesh, removing the powder adhering to the classification mesh after classification; A classification method characterized by:

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