Powder-processing device, and powder-processing method using same

Abstract

The present invention provides the following configuration in order to provide a foreign matter removal method and a foreign matter removal device capable of processing a large amount of powder in a practical device size.　This powder-processing device comprises: a base plate on which powder can be placed; a plurality of processing parts that process the powder placed on the base plate; and a base plate conveyance mechanism that conveys the base plate between the plurality of processing parts. More preferably, the plurality of processing parts include at least: a) a powder supply part that places the powder to be processed on the base plate; b) a classification part that classifies the powder placed on the base plate according to the particle size; and c) a recovery part that recovers, from the powder subjected to the classification process, good-quality products which do not include foreign matter.

Description

Powder processing device and powder processing method using the same

[0001] The present invention relates to a powder processing apparatus for performing powder processing such as removing foreign particles mixed in powder, and a powder processing method using the same.

[0002] Patent Document 1 discloses a known technology for removing foreign particles mixed in powder. This patent document describes a foreign matter removal method including, in the vicinity of a transparent or translucent turntable that rotates with powder on its surface to transport the powder, a supply device that supplies powder to the turntable surface, a photography device that photographs the powder on the turntable surface to detect defective products, a non-defective product recovery nozzle that sucks and recovers non-defective products from the powder on the turntable surface after the photography, and a defective product removal nozzle that sucks and removes all of the powder on the turntable surface after the non-defective products have been recovered, all of which are arranged in this order in the direction of rotation of the turntable, and the photography device includes at least a front-side photography mechanism that photographs the powder on the turntable surface from the front side of the turntable and a back-side photography mechanism that photographs the powder on the turntable surface from the back side.

[0003] Japanese Patent Application Laid-Open No. 2004-157027

[0004] In the technology described in Patent Document 1, powder can only be placed near the periphery of the turntable. Therefore, in order to increase the amount of powder that can be processed, the diameter of the turntable must be increased, which results in an enormous device size when a large amount of powder needs to be processed.

[0005] The present invention has been made in consideration of the above problems, and its purpose is to provide a powder processing device that can process large amounts of powder with a realistic device size, and a powder processing method using the same.

[0006] The present invention achieves the above object by providing a powder processing apparatus including: a substrate on which powder can be placed, a plurality of processing sections for processing the powder placed on the substrate, and a substrate transport mechanism for transporting the substrate between the plurality of processing sections.

[0007] According to the present invention, it is possible to provide a powder processing apparatus that can process a large amount of powder with a practical device size, and a powder processing method using the same.

[0008] 1 is a top view showing a schematic configuration of a powder processing apparatus (foreign matter removal apparatus) according to Example 1. FIG. 2 is a cross-sectional view showing the structure of a supply unit in Example 1. FIG. 3 is a cross-sectional view showing the structure of a classifying unit in Example 1. FIG. 4 is a cross-sectional view showing the structure of an imaging unit in Example 1. FIG. 5 is a cross-sectional view showing the structure of a recovery unit in Example 1. FIG. 6 is a cross-sectional view showing the structure of a classifying unit in Example 2. FIG. 7 is a top view showing the opening shape of a mask in Example 2. FIG. 8 is a top view showing a schematic configuration of a powder processing apparatus (foreign matter removal apparatus) according to Example 3. FIG. 9 is a cross-sectional view showing the structure of a recovery unit in Example 3.

[0009] 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.

[0010] 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.

[0011] 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.

[0012] Example 1 will be described with reference to Figures 1 to 5. Figure 1 is a top view showing a schematic configuration of a powder processing apparatus (which may also be called a "foreign matter removal apparatus" in light of its purpose of removing foreign matter; in the following examples, it will be called a "foreign matter removal apparatus") according to Example 1. The foreign matter removal apparatus 1 in this example includes a supply unit (also called a "powder supply unit") 2, a classifier 3, an imaging unit 4, a recovery unit 5, four substrate transport mechanisms 6, and four substrates 7.

[0013] The substrate 7, with the powder placed thereon, is transported between the processing sections (supply section 2, classification section 3, imaging section 4, and recovery section 5) by the substrate transport mechanism 6. The substrate 7 can be made of a plate material such as metal, ceramics, or resin, with a sufficient thickness to minimize deformation during transport. To prevent contamination of the powder, it is desirable to apply a fluororesin coating, PEEK coating, or DLC coating to the surface of the substrate 7, or an anodized aluminum coating to the surface of the substrate 7.

[0014] The substrate transport mechanism 6 transports the substrate 7 between each processing section, and includes a hand 8, a suction pad 9, a linear motion mechanism 10, and a rotation mechanism 11. The substrate 7 placed in each processing section is attracted to and fixed to the hand 8 by a suction pad that utilizes negative pressure, for example, and is transported by the linear motion mechanism 10 to directly above the rotation mechanism 11. Thereafter, the substrate 7 is rotated 180° by the rotation mechanism 11 and transported to the next processing section by the linear motion mechanism 10. In the above example, there are four processing sections: a supply section 2, a classification section 3, an imaging section 4, and a recovery section 5, and each processing section is connected by four substrate transport mechanisms 6, and four substrates 7 are transported in parallel. However, as explained in the section [Effects of the Invention], the effect of the present invention is to "provide a powder processing apparatus that can process large amounts of powder with a realistic apparatus size, and a powder processing method using the same." In order to achieve this effect, it is sufficient to have "a substrate on which powder can be placed, a plurality of processing sections that process the powder placed on the substrate, and a substrate transport mechanism that transports the substrate between the plurality of processing sections" as described in [Claim 1], and it goes without saying that the configuration described in Example 1 is not an essential configuration.

[0015] The supply unit 2 is used to set (place, i.e., temporarily place) powder to be processed on a substrate 7. Fig. 2 is a cross-sectional view showing the structure of the supply unit 2 in Example 1. Fig. 2(a) shows the state at the time of setting, and Fig. 2(b) shows the state at the time of supplying powder. The supply unit 2 includes a hopper 12, a feeder 13, a squeegee 14, a mask 15, a support 16, a lifting mechanism 17, a suction pad 18, a base plate 19, and a linear motion mechanism 20.

[0016] The mask 15 is a plate material with an opening 100 in the center, and the shape of the opening corresponds to the shape of the powder layer to be supplied onto the substrate 7 (typically, the opening shape is rectangular). The mask 15 can be made of a plate material such as metal, ceramic, or resin. To prevent contamination of the powder, it is desirable to apply a fluororesin coating, PEEK coating, DLC coating, or, in the case of aluminum, an anodizing treatment to the surface of the mask 15. The mask 15 is fixed to a base plate 19 via supports 16.

[0017] A predetermined amount of powder 21 is stored in hopper 12. During the setting shown in Fig. 2(a), a predetermined amount of powder 21 in hopper 12 is supplied by feeder 13 to the space between squeegee 14 and mask 15. Meanwhile, substrate 7 is placed on lifting mechanism 17 by substrate transport mechanism 6 and fixed by suction pad 18.

[0018] 2(b), during powder supply, the substrate 7 is raised by the lifting mechanism 17 and abutted against the mask 15. Thereafter, the base plate 19 is moved horizontally by the linear motion mechanism 20. At this time, the powder 21 that was supplied between the squeegee 14 and the mask 15 when the substrate was set is supplied onto the substrate 7. The powder supplied onto the substrate 7 is scraped off by the squeegee 14 and spread to the same thickness as the plate thickness of the mask 15. As a result, a powder layer of a size corresponding to the opening 100 of the mask 15 is formed on the substrate 7.

[0019] The classifying unit 3 exposes foreign particles to the surface of the powder bed through classification. Figure 3 is a cross-sectional view showing the structure of the classifying unit 3 in Example 1. Figure 3(a) shows the state during setup, Figure 3(b) shows the state during classification, and Figure 3(c) shows the state during mesh-passed powder collection. The classifying unit 3 includes an ultrasonic vibrator 22, a mesh fixing frame 23, a space-forming mesh 24, a classification mesh (sieve) 25, vibration plates 26a and 26b, a support 27, an elevating mechanism 28, a linear motion mechanism 29, a mesh-passed powder collection nozzle 30, an air injection nozzle 31, and a clogging powder collection nozzle 32.

[0020] The ultrasonic vibrator 22 is fixed to vibration plates 26a and 26b. The upper vibration plate 26a is fixed to a support 27. The lower vibration plate 26b is fixed to an elevation mechanism 28. The space forming mesh 24 and the classification mesh 25 are fixed to a mesh fixing frame 23.

[0021] The classification mesh 25 has a mesh size (mesh coarseness) that is equal to or smaller than the lower limit of the foreign particle size to be removed and larger than the median particle size of the powder 21. Here, even if the mesh size of the classification mesh 25 is slightly larger than the foreign particle size, substantial removal of the foreign particles is possible and throughput is improved; however, a mesh size smaller than the foreign particle size allows for more reliable removal and increases reliability. The space-forming mesh 24 is installed on the classification mesh 25 and is a mesh with a thick wire to provide a thickness, forming multiple spaces for accommodating the powder that has passed through the classification mesh 25. The horizontal cross-sectional area of ​​each space in the space-forming mesh 24 is larger than the cross-sectional area of ​​each opening in the classification mesh 25. In other words, the mesh size of the space-forming mesh 24 is larger than the mesh size of the classification mesh 25. Furthermore, multiple space-forming meshes 24 may be installed in layers depending on the volume of powder that passes through the classification mesh 25. If it is desired to prevent metallic foreign matter originating from the mesh from being mixed into the powder, it is desirable to use a resin mesh such as nylon as the material for the classification mesh 25 and the space forming mesh 24 .

[0022] The mesh fixing frame 23 can be moved horizontally by a linear motion mechanism 29. It can also move freely in the vertical direction, rising together with the substrate 7 that rises during classification, and can be pressed against the upper vibration plate 26a.

[0023] The vibration plates 26a and 26b are preferably made of a hard material such as metal to suppress energy attenuation of the ultrasonic vibrators. To prevent contamination of the powder, the surfaces of the vibration plates 26a and 26b are preferably coated with fluororesin, PEEK, or DLC, or if made of aluminum, are preferably anodized.

[0024] 3(a), the substrate 7 carrying the powder 21 is placed on the lower vibration plate 26b by the substrate transport mechanism 6 (not shown in FIG. 3). The mesh fixing frame 23 is placed on the powder 21.

[0025] During classification, as shown in FIG. 3(b), the lower vibration plate 26b is raised by the lifting mechanism 28, pressing the space-forming mesh 24, the classification mesh 25, the powder 21, and the substrate 7 between the upper and lower vibration plates 26a and 26b (due to this function, the lifting mechanism 28 is also referred to as a "pressing mechanism"). High-frequency power is then applied to the ultrasonic vibrator 22, causing it to vibrate. This fluidizes the powder 21, and particles smaller than the mesh size of the classification mesh 25 pass through the classification mesh 25. Applying vibrations while pressing against the powder 21 can break down agglomerates and fluidize even highly adhesive powder. The classification time is set so that the thickness of the powder layer below the classification mesh 25 is approximately the same as or smaller than the size of the foreign particle to be removed. This causes at least a portion of the foreign particle to be removed to be exposed at the surface of the powder layer.

[0026] During classification, a control unit (not shown) controls the lifting mechanism 28 to adjust the height of the vibration plate 26b so that the height can follow the decrease in the powder layer thickness that occurs as the powder 21 passes through the classification mesh 25. Alternatively, the vibration plate 26b may be made to follow the decrease by an elastic member such as a spring.

[0027] 3(c), during the mesh-passing powder recovery process, the mesh fixing frame 23 is moved to the right in the drawing by a linear motion mechanism 29 (due to this function, the linear motion mechanism 29 is also referred to as the "sieve moving mechanism"). At this time, the powder 21 that has passed through the classification mesh 25 is suction-recovered by a mesh-passing powder recovery nozzle 30 as a non-defective product that does not contain foreign particles (due to this function, the mesh-passing powder recovery nozzle 30 is also referred to as the "suction mechanism"). Furthermore, air is sprayed toward the mesh from an air injection nozzle 31, and particles clogging the mesh are suction-recovered by a clogging powder recovery nozzle 32. The substrate 7 carrying the powder that did not pass through the classification mesh 25 is then carried out by the substrate transport mechanism 6. In the above embodiment, classification processing using a sieve (mesh) is described as an example. However, if the particle size of the foreign matter contained in the powder to be processed and to be sieved out is larger than the particle size of the non-defective product, the powder can be crushed with a pressure plate to expose the foreign matter on the surface of the powder layer, and the foreign matter can be separated using the imaging unit 4 and recovery unit 5 described below. In this case, a sieve is not used. This type of foreign matter separation method is also referred to as "classification processing" in the present invention. In the present invention, various well-known foreign matter separation methods can be applied depending on the type of foreign matter to be separated and the properties of the powder containing the foreign matter.

[0028] The imaging unit 4 detects foreign particles exposed on the powder bed surface. FIG. 4 is a cross-sectional view showing the structure of the imaging unit 4 in Example 1. The imaging unit 4 includes an illumination 36, a lens 35, a CCD 33, an image processing unit 34, a support 37, a base plate 39, and linear motion mechanisms 40 and 41. The illumination 36 irradiates the powder 21 from the imaging unit 4 side, and is, for example, a ring light. The lens 35 is attached to the CCD 33, and the CCD 33 acquires an image of the powder surface at an appropriate magnification. The acquired image is analyzed by the image processing unit 34 to determine the presence or absence of foreign particles (due to this function, the image processing unit 34 is also referred to as a "determination mechanism"). Methods for identifying foreign particles include, for example, methods that utilize differences in particle shape, the light intensity or color of reflected or scattered light, etc. The substrate 7 carrying the powder 21 is fixed to the support 37 by an adsorption pad 38. The support 37 is fixed to the base plate 39. The base plate 39 is fixed to a linear motion mechanism 40. The linear motion mechanism 40 is fixed so as to be perpendicular to the linear motion mechanism 41. This allows the substrate 7 to be moved two-dimensionally in the horizontal direction, thereby making it possible to capture an image of the entire surface of the powder 21.

[0029] Although the present embodiment describes an example in which two linear motion mechanisms are used that are perpendicular to each other, the width of the powder layer may be set to be equal to or less than the imaging field of view, and imaging may be performed using only one linear motion mechanism. Alternatively, multiple cameras may be installed to widen the imaging field of view.

[0030] The recovery unit 5 recovers non-defective products that do not contain foreign particles or discharges defective products that contain foreign particles based on the results of the determination made by the imaging unit 4. Fig. 5 is a cross-sectional view showing the structure of the recovery unit 5 in Example 1. The recovery unit 5 includes a non-defective product recovery nozzle 42, a defective product recovery nozzle (also referred to as a foreign matter removal mechanism) 60, a support 43, a base plate 45, and linear motion mechanisms 46 and 47.

[0031] The substrate 7 carrying the powder 21 is fixed to a support 43 by a suction pad 44. The support 43 is fixed to a base plate 45. The base plate 45 is fixed to a linear motion mechanism 46. The linear motion mechanism 46 is fixed perpendicular to the linear motion mechanism 47. If the imaging unit 4 detects the presence of foreign particles, the linear motion mechanisms 46 and 47 move the area where the foreign particles are detected under the defective product recovery nozzle 60 and suction-recovery is performed. After the foreign particles are collected, the remaining powder is suction-recovery performed by the non-defective product recovery nozzle 42. The tip size of the defective product recovery nozzle 60 is preferably small so as to minimize the suction of powder other than foreign particles. However, to prevent nozzle clogging, it is preferable to set the tip size to at least three times the diameter of the foreign particles to be removed. The non-defective product recovery nozzle 42 is preferably a wide nozzle to shorten the suction-recovery time.

[0032] The substrate 7 from which the powder 21 has been collected and removed in the collection section 5 is introduced again into the supply section 2 by the substrate transport mechanism 6 (not shown in FIG. 5).

[0033] In this embodiment, an example using two linear motion mechanisms that are perpendicular to each other has been described, but it is also possible to use only one linear motion mechanism and make the good product collection nozzle 42 and the defective product collection nozzle 60 wide nozzles to perform collection by moving on only one axis.

[0034] As described above, according to this embodiment, the ratio of the powder installation area to the equipment area can be increased, making it possible to process a large amount of powder with an equipment of a realistic size.

[0035] In this embodiment, an example has been described in which the powder is classified before being introduced into the imaging unit 4, but instead of using a mesh, a process of spreading the powder layer thinly by pressing or scraping may be performed instead of classification. Also, in this embodiment, an example has been described in which a linear motion mechanism and a rotation mechanism are combined as the substrate transport mechanism, but a transport mechanism using a belt conveyor may also be used.

[0036] Example 2 will be described with reference to Figures 6 and 7. Figure 6 is a cross-sectional view showing the structure of the classification unit in Example 2. In Example 1, if the powder layer placed on the substrate is thickened to increase the throughput, the thickness of the space-forming mesh must be increased or multiple space-forming meshes must be stacked to accommodate the corresponding amount of powder. However, in this case, the space-forming mesh absorbs a lot of vibration energy, slowing the speed at which the powder passes through the classification mesh. Therefore, Example 2 eliminates the need for a space-forming mesh and improves the throughput by suction-collecting the powder that has passed through the classification mesh simultaneously with classification. The overall configuration of the foreign matter removal device in Example 2 is the same as that of Example 1 shown in Figure 1, but the configuration of the classification unit 3 and the opening shape of the mask 15 in the supply unit 2 differ from those in Example 1.

[0037] Figure 6(a) shows the state during setup, Figure 6(b) shows the state during classification, and Figure 6(c) shows the state during mesh cleaning. The classifier 3 of Example 2 includes an ultrasonic vibrator 22, a mesh fixing frame 23, a classification mesh 25, a vibration plate 26, a lifting mechanism 28, a linear motion mechanism 29, an air injection nozzle 31, a clogging powder recovery nozzle 32, a suction housing 48, opening plates 49 and 50, and an ultrasonic vibrator 51. The ultrasonic vibrator 22, the classification mesh 25, the mesh fixing frame 23, and the vibration plate 26 are the same as those of Example 1, so their description will be omitted.

[0038] Two aperture plates 49 and 50 are attached to the suction housing 48. The aperture plates are designed to flatten the shape of the classification mesh 25 when it is pressed against the powder. They are highly rigid plates with multiple vertically penetrating apertures for powder suction. To reduce suction unevenness due to open / closed positions, it is desirable to increase the aperture ratio by making each aperture small and arranging them densely. However, this reduces rigidity and may lead to deformation during pressing. Deformation of the aperture plates causes the classification mesh to deform, changing the mesh opening shape and preventing the expected classification performance. Furthermore, for materials with an average particle size of several microns to several tens of microns, such as electrode materials for lithium-ion batteries, classification meshes with openings of 100 μm or less are often used. However, such meshes are weak and may tear if deformed significantly. Therefore, by installing two aperture plates with different aperture sizes and aperture ratios, both suppression of suction unevenness and rigidity can be achieved. The aperture size of the aperture plate 50 is made smaller than that of the aperture plate 49, and the apertures are arranged at a higher density to increase the aperture ratio.

[0039] If it is desired to prevent metallic foreign matter from being mixed into the powder 21, it is desirable to form the aperture plates 49, 50 and the suction housing 48 from a non-metallic material such as resin, but if sufficient rigidity cannot be obtained, they may be formed from a metal such as stainless steel or aluminum. In this case, it is desirable to form a non-metallic layer, such as a resin coating such as fluororesin or a DLC coating, on the areas that come into contact with the powder 21. Furthermore, if sufficient rigidity can be obtained with the aperture plate 49 alone, the aperture plate 50 may be made of a resin mesh such as nylon.

[0040] 6(a), the substrate 7 carrying the powder 21 is placed on the vibration plate 26 by the substrate transport mechanism 6 (not shown in FIG. 6). The mesh fixing frame 23 is placed on the powder 21.

[0041] During classification, as shown in FIG. 6( b), the vibration plate 26 is raised by the lifting mechanism 28, and the classification mesh 25, powder 21, and substrate 7 are pressed against each other by the vibration plate 26 and the aperture plates 49 and 50. High-frequency power is then applied to the ultrasonic vibrator 22, causing it to vibrate. This fluidizes the powder, and particles smaller than the mesh openings of the classification mesh 25 pass through the classification mesh 25. Applying vibration while pressing against the powder 21 breaks down agglomerates and fluidizes even highly adhesive powder. By simultaneously applying suction while applying vibration, the powder 21 that passes through the classification mesh 25 is suction-collected via the suction housing 48. Furthermore, applying vibrations using the ultrasonic vibrator 51 attached to the suction housing 48 further promotes fluidization, increasing the speed at which the powder passes through the classification mesh 25. The classification time is set so that the thickness of the powder layer below the classification mesh 25 is approximately the same as or smaller than the size of the foreign particle to be removed. This ensures that at least a portion of the foreign particle to be removed is exposed on the surface of the powder layer.

[0042] During classification, a control unit (not shown) controls the lifting mechanism 28 to adjust the height of the vibration plate 26 so as to follow the decrease in the powder layer thickness that occurs as the powder 21 passes through the classification mesh 25. Alternatively, the vibration plate 26 may be made to follow the decrease by an elastic member such as a spring.

[0043] 6(c), during mesh cleaning, the mesh fixing frame 23 is moved to the right in the figure by the linear motion mechanism 29. At this time, air is sprayed toward the mesh from the air spray nozzle 31, and particles clogging the mesh are sucked and collected by the clogging powder collection nozzle 32 (due to this function, the air spray nozzle 31 is also referred to as a "cleaning mechanism"). In Example 1, this operation was performed for each classification cycle, but in this example, cleaning may be performed every predetermined number of classification cycles if the probability of mesh clogging is low.

[0044] FIG. 7 is a top view showing the shape of the openings of the mask 15 in Example 2. The mask 15 has multiple openings 52. This allows multiple powder layers of the same size as the openings 52 to be formed on the substrate 7. During classification, in order to suck the powder 21, it is necessary to create an air flow from the outside toward the suction housing 48. If the powder layer is completely covered (for example, as in Example 1), the center of the powder layer cannot be sucked because there is no path for air to enter. In contrast, in this example, a path for air to flow all the way to the center of the substrate 7 can be created, allowing powder to be sucked over the entire surface.

[0045] As described above, according to this embodiment, the powder 21 that has passed through the classification mesh 25 is suction-collected simultaneously with classification, thereby making the space-forming mesh 24 unnecessary and improving the throughput.

[0046] In this embodiment, an example has been described in which two aperture plates 49, 50 with different apertures are installed, but it may be configured with a single aperture plate as long as it is possible to achieve both the flatness of the classification mesh 25 and the suppression of uneven suction.

[0047] Example 3 will be described with reference to Figures 8 and 9. In Examples 1 and 2, for example, when the foreign particles to be detected become small, it is necessary to narrow the field of view and increase the imaging resolution, which may result in an insufficient imaging throughput. Therefore, in this example, primary classification is performed to reduce the amount of powder required for imaging and improve the throughput.

[0048] 8 is a top view showing a schematic configuration of a foreign matter removal apparatus according to Example 3. The foreign matter removal apparatus 1 is made up of a primary classification unit 53, a foreign matter removal unit 54, and a transport system 56.

[0049] The primary classification unit 53 includes a supply unit 2, a classification unit 3, a collection unit 55, and a substrate transport mechanism 6, and performs classification only without detecting foreign matter by imaging. The configurations of the supply unit 2 and the classification unit 3 are the same as those of Example 1 or Example 2. Figure 9 is a cross-sectional view showing the configuration of the collection unit 55. The collection unit 55 includes a collection nozzle 42, a support 43, a base plate 45, and a linear motion mechanism 46.

[0050] The recovery nozzle 42 is a wide nozzle having a width equal to or greater than the width of the powder layer. The substrate 7 carrying the powder 21 is fixed to a support 43 by an adsorption pad 44. The support 43 is fixed to a base plate 45. The base plate 45 is fixed to a linear motion mechanism 46. After the classification process, the powder remaining on the substrate 7 is sucked and recovered by the recovery nozzle 42 while being moved by the linear motion mechanism 46. The substrate 7 from which the powder 21 has been recovered and removed in the recovery section 55 is introduced again into the supply section 2 by the substrate transport mechanism 6. The powder sucked and recovered in the recovery section 55 is introduced into the hopper 12 of the supply section 2 of the foreign matter removal unit 54 by the transport system 56.

[0051] The configuration of the foreign matter removal unit 54 is the same as in Example 1 or Example 2, and the powder introduced into the hopper 12 passes through the classifying section 3 and the imaging section 4, and is then removed of foreign matter in the collecting section 5. According to this example, the throughput can be improved by performing primary classification in advance.

[0052] In this embodiment, an example has been described in which powder is transported directly from the primary classification unit 53 to the foreign matter removal unit 54 using the transport system 56, but an intermediate tank may be provided and the powder recovered in the primary classification unit may be stored in the intermediate tank before being introduced into the foreign matter removal unit 54.

[0053] 1...foreign matter removal device, 2...supply section, 3...classification section, 4...imaging section, 5...recovery section, 6...substrate transport mechanism, 7...substrate, 12...hopper, 13...feeder, 14...squeegee, 15...mask, 22...ultrasonic vibrator, 23...mesh fixing frame, 24...space forming mesh, 25...classification mesh, 26a, 26b...vibration plate, 30...mesh-passed powder recovery nozzle, 31...air injection nozzle, 32...clogging powder recovery nozzle, 33...CCD, 34...image processing section, 35...lens, 36...lighting, 42...good product recovery nozzle, 60...defective product recovery nozzle, 48...suction housing, 49, 50...opening plate, 53...primary classification unit, 54...foreign matter removal unit, 56...transport system

Claims

1. A powder processing apparatus comprising: a substrate on which powder can be placed; a plurality of processing sections for processing the powder placed on the substrate; and a substrate transport mechanism for transporting the substrate between the plurality of processing sections.

2. A powder processing apparatus according to claim 1, wherein the plurality of processing sections include at least: a) a powder supply section which places the powder to be processed on the substrate; b) a classification section which separates the powder placed on the substrate by particle size; and c) a recovery section which recovers non-defective products that do not contain foreign matter from the classified powder.

3. A powder processing apparatus according to claim 1, further comprising a plurality of said substrate transport mechanisms, each of said plurality of substrate transport mechanisms being capable of transporting a different substrate independently.

4. A powder processing apparatus according to claim 1, wherein the substrate is transported in a circulating manner through the plurality of processing sections.

5. A powder processing apparatus according to claim 2, wherein the classifying section comprises at least a vibration mechanism for vibrating a sieve for classifying the powder, and a pressing mechanism for pressing the sieve against the powder while the vibration mechanism vibrates the sieve.

6. A powder processing apparatus according to claim 5, further comprising a suction mechanism for sucking the powder that has passed through the sieve by the pressing mechanism pressing the powder.

7. A powder processing apparatus according to claim 5, characterized in that the pressing mechanism on the side in contact with the sieve is formed with a plurality of openings penetrating vertically.

8. A powder processing apparatus according to claim 2, wherein the powder supplying section is provided with a mask for dividing the powder into a plurality of blocks and placing the blocks on the substrate.

9. A powder processing apparatus according to claim 2, wherein the classifying section is provided with a cleaning mechanism for cleaning the sieve after classification.

10. A powder processing apparatus according to claim 2, further comprising a sieve moving mechanism for moving the sieve that has been classified in the classification section to the recovery section and recovering the powder that has passed through the sieve.

11. A powder processing apparatus according to claim 2, further comprising an imaging section for imaging the powder that has been classified by the classifier, the imaging section further comprising a determination mechanism for determining whether or not the classified powder contains foreign matter based on the captured image.

12. A powder processing apparatus according to claim 11, characterized in that the recovery section is equipped with a foreign matter removal mechanism that recovers non-defective products that do not contain foreign matter based on the judgment result of the judgment mechanism of the imaging section, and removes powder that is judged to contain foreign matter by the judgment mechanism.

13. A powder processing method using the powder processing apparatus according to any one of claims 1 to 12.

14. A powder processing method using a powder processing apparatus including a substrate on which powder can be placed, a plurality of processing sections for processing the powder placed on the substrate, and a substrate transport mechanism for transporting the substrate between the plurality of processing sections, wherein the plurality of processing sections include at least a) a powder supply section for placing the powder to be processed on the substrate, b) a classification section for separating the powder placed on the substrate by particle size, and c) a recovery section for recovering non-defective products that do not contain foreign matter from the classified powder, wherein the classification process is performed by transporting the powder to be processed through the powder supply section, the classification section, and the recovery section in that order.

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