Fluidization device

Abstract

To provide a fluidizing device that can more easily fluidize powder or granular material. [SOLUTION] The fluidizer 1 is attached to the inner wall surface of a container that has a discharge port and into which powder or granular material is fed, and includes an elastic body having a truncated cone-shaped side surface that widens from one end to the other, with the other end abutting the inner wall surface to form a space between it and the inner wall surface, and a supply pipe that is attached to close one end, penetrates the side wall via the space, and supplies compressed air from the outside to the space. The elastic body contains stainless steel powder as an additive material, and is configured to eject compressed air from the space to the outside of the elastic body when the internal pressure due to the compressed air reaches or exceeds a predetermined value.

Description

[Technical Field]

[0001] The present invention relates to a fluidizing device, and more particularly to a fluidizing device that is attached to a container such as a tank for temporarily storing powder or granular material. [Background technology]

[0002] Patent Document 1 shows a fluidizing device that can be attached to a container such as a tank for temporarily storing powder or granular material.

[0003] FIG. 5 is a schematic cross-sectional view showing a conventional fluidization device disclosed in Patent Document 1.

[0004] Referring to Figure 5, the fluidization device 50 is composed of an air nozzle 51 to which compressed air is supplied, an umbrella-shaped elastic body 52 connected to one end of the air nozzle 51, and an air pulser 53 connected to the other end of the air nozzle 51.

[0005] The air pulser 53 has a diaphragm valve 56 provided therein, and when the diaphragm valve 56 is opened, compressed air is instantly ejected into the container.

[0006] When using the fluidizer 50, the air nozzle 51 is fixed so as to penetrate the wall surface 57 of the container, the elastic body 52 is positioned on the inner wall surface 58 side, and the air pulser 53 is positioned on the outer wall surface 59 side. Compressed air is then intermittently injected into the air passage 54 and sent to the space 55, increasing the pressure within the space 55, which elastically deforms the elastic body 52 in a direction that flattens it. This deformation forms a gap between the outer periphery of the elastic body 52 and the inner wall surface 58, and air within the space 55 is blown into the container through the gap. In this way, the powder and granular material filled in the container is fluidized by the blown-in air, and the powder and granular material weight causes the upper part of the discharge port to solidify into an arch-like shape, eliminating the blockage (bridging of powder and granular material) at the top of the discharge port. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-34429 Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the conventional fluidizing devices as described above, there are cases where the powder or granules are not fluidized depending on the type and amount of the powder or granules, and there is still room for improvement.

[0009] The present invention has been made to solve the above-mentioned problems, and has an object to provide a fluidizing device that can more easily fluidize powder or granular material. [Means for solving the problem]

[0010] In order to achieve the above object, the invention described in claim 1 is a fluidization device that is attached to the inner wall surface of a side wall of a container into which powder or granular material is introduced and which has a discharge outlet, and is equipped with an elastic body having a truncated conical side shape that widens from one end to the other end, the other end of which abuts against the inner wall surface to form a space between it and the inner wall surface, and a supply pipe that is attached to close one end, penetrates the side wall through the space, and supplies compressed air from the outside to the space, and the elastic body contains stainless steel powder as an additive material, and is configured to eject compressed air from the space to the outside of the elastic body when the internal pressure caused by the compressed air reaches a predetermined value or higher.

[0011] In this configuration, the inclusion of stainless steel powder increases the rigidity of the elastic body and increases the predetermined value compared to when stainless steel powder is not included. The stainless steel powder is contained in the part where fine, high-frequency vibrations occur when compressed air is ejected.

[0012] The invention of claim 2 is the same as the invention of claim 1, in which the stainless steel powder is contained in an amount of 30% by weight to 70% by weight with respect to 100% by weight of the elastic body.

[0013] With this construction, even if fragments of the elastic body are mixed in with the powder or granular material, they can be easily detected by a metal detector. Also, high tear strength against pressure from compressed air can be maintained.

[0014] The invention of claim 3 is the configuration of the invention of claim 1 or claim 2, in which the elastic material of the elastic body is made of silicone rubber, and the hardness of the elastic body is 40 to 80 degrees.

[0015] With this configuration, the elastic body is resistant to tearing, and the attachment state between the elastic body and the supply pipe can be maintained when compressed air is supplied.

[0016] The invention as set forth in claim 4 is the same as the invention as set forth in claim 1 or claim 2, in which the maximum particle size of the stainless steel powder is in the range of 20 μm or more and 100 μm or less.

[0017] With this configuration, it is possible to easily prepare stainless steel powder that can be uniformly dispersed.

[0018] The invention described in claim 5 is the same as the invention described in claim 1 or claim 2, in which the surface of the elastic body is not plated with metal or painted with a coating agent as the additive material used therein, and no agent for rust prevention is mixed into the elastic material.

[0019] With this configuration, plating, coating agents, and anti-rust agents are not used on the elastic body. [Effects of the Invention]

[0020] As explained above, in the invention of claim 1, the inclusion of stainless steel powder increases the rigidity of the elastic body, and the predetermined value is larger than when stainless steel powder is not included, so the ejection speed of compressed air increases and the powder and granular material becomes easier to flow. Furthermore, because the stainless steel powder is contained in the part where fine, high-frequency vibrations occur when compressed air is ejected, even if part of the fluidizing device is chipped during use, it can be detected by a metal detector.

[0021] In addition to the effect of the invention of claim 1, the invention of claim 2 makes it possible for fragments of the elastic body to be easily detected by a metal detector even if they are mixed in with powder or granular material, making it a fluidizing device suitable for the food industry, etc. Also, since it can maintain high tear strength against the pressure of compressed air, the elastic body is less likely to break even if the jet speed of compressed air increases.

[0022] The invention described in claim 3 has the effects of the invention described in claim 1 or claim 2, and in addition, is tear-resistant and can maintain the attachment state between the elastic body and the supply pipe when compressed air is supplied, making it suitable for a fluidization device.

[0023] The invention described in claim 4, in addition to the effects of the invention described in claim 1 or claim 2, makes it possible to easily produce stainless steel powder that can be uniformly dispersed, thereby achieving both cost benefits and stable quality.

[0024] The invention of claim 5 has the same effects as the invention of claim 1 or claim 2, and in addition, does not require plating, coating agents, or anti-rust agents on the elastic body, making it a fluidization device suitable for use in the food industry and other fields. [Brief explanation of the drawings]

[0025] [Figure 1] FIG. 1 is a schematic diagram showing a tank using a fluidization device according to an embodiment of the present invention. [Figure 2] 2 is a front view of the fluidization device according to the embodiment of the present invention, and is an enlarged front view of the portion "A" shown in FIG. 1 as seen from the inner wall surface side. [Figure 3] FIG. 3 is a schematic cross-sectional view of line III-III of the fluidization device shown in FIG. 2. [Figure 4] FIG. 2 is a schematic cross-sectional view showing the fluidization device shown in FIG. 1 in use. [Figure 5] FIG. 1 is a schematic cross-sectional view showing a conventional fluidization device disclosed in Patent Document 1. DETAILED DESCRIPTION OF THE INVENTION

[0026] FIG. 1 is a schematic diagram showing a tank using a fluidization device according to an embodiment of the present invention.

[0027] 1, tank 41 is a container that opens in the vertical direction for temporarily storing raw materials, and has a funnel-shaped side wall 42. Tank 41 has a raw material inlet 43 on the upper side and a discharge outlet 44 on the lower side. Tank 41 is installed in, for example, a food factory, and discharges powder or granular material introduced through inlet 43 from discharge outlet 44. A plurality of fluidizers 1 (1a to 1c) are attached to an inner wall surface 45 of side wall 42 of tank 41.

[0028] FIG. 2 is a front view of a fluidization device according to an embodiment of the present invention, and is an enlarged front view of part "A" shown in FIG. 1 as seen from the inner wall surface side, and FIG. 3 is a schematic cross-sectional view of line III-III of the fluidization device shown in FIG. 2.

[0029] Referring to Figures 2 and 3, the fluidization device 1 is composed of an elastic body 10 having a truncated conical side shape that widens from one end 11 to the other end 12, and a supply pipe 20 that is attached to close one end 11 and supplies compressed air from the outside.

[0030] The elastic body 10 is open in the vertical direction, and is integrated with the supply pipe 20 with the supply pipe 20 inserted into one end 11. In a side view, the elastic body 10 extends a certain distance from one end 11 along the supply pipe 20, and then extends away from the supply pipe 20 to the other end 12, slanting diagonally downward. With this configuration, the elastic body 10 abuts against the entire circumference of the supply pipe 20, thereby firmly attaching the elastic body 10 to the supply pipe 20. Furthermore, the thickness of the elastic body 10 is set to gradually decrease toward the tip at the other end 12. This makes the other end 12 more susceptible to vibration by compressed air.

[0031] The elastic material of the elastic body 10 is made of silicone rubber. The elastic body 10 also contains stainless steel powder as an additive material (a material mixed with the elastic material). Details of the elastic body 10 will be described later.

[0032] The supply pipe 20 is a pipe with a closed tip 21. As described above, the side surface near the tip 21 and the elastic body 10 are integrated, and the supply pipe 20 extends from the inner surface 13 of the elastic body 10 toward the attachment target (the side wall 42 of the tank 41). Four outlets 22 (22a-22d) are formed at predetermined intervals around the periphery of the side surface of the supply pipe 20 for flowing compressed air toward the space 2 described below. This configuration allows the compressed air to flow in all directions, ensuring uniform distribution of the compressed air throughout the entire inner surface 13 of the elastic body 10. A spiral groove (not shown) is formed on the side surface of the supply pipe 20, which is the supply source from the outlets 22. This configuration allows the fluidizer 1 to be fixed at a predetermined position on the side wall 42 of the tank 41 using washers 23 and nuts 24.

[0033] Next, a method for using the fluidizing device 1 will be described.

[0034] FIG. 4 is a schematic cross-sectional view showing the fluidization device shown in FIG. 1 in use.

[0035] Referring to FIG. 4 , first, a through-hole (not shown) is formed in a side wall 42 of a tank 41 at a position corresponding to the mounting location of the fluidizer 1. Next, an elastic body 10 is placed on an inner wall surface 45 of the portion where the through-hole is formed, and a supply pipe 20 is inserted through the through-hole. The fluidizer 1 is then installed so that the other end 12 of the elastic body 10 abuts against the inner wall surface 45. Thereafter, a washer 23 and a nut 24 are fastened to the supply pipe 20 from the outer wall surface 46 side of the tank 41, and the fluidizer 1 is fixed to the tank 41. At this time, the other end 12 of the elastic body 10 is in close contact with the inner wall surface 45, so that a space 2 is formed between the inner wall surface 45 and the inner surface 13 side of the elastic body 10.

[0036] Next, compressed air is intermittently supplied to supply pipe 20 by an externally installed timer and solenoid valve (not shown). As a result, compressed air is supplied from the outside to space 2 as shown by arrows 30 and 31 in FIG. 4. When compressed air accumulates in space 2, the internal pressure causes the compressed air to try to be ejected to the outside as shown by arrow 32 in FIG. 4. When the internal pressure reaches a predetermined value or higher, the entire circumference of other end 12 of elastic body 10 is pushed up in a direction away from inner wall surface 45, and compressed air is ejected from space 2 to the outside of elastic body 10 as shown by arrow 33 in FIG. 4. In other words, gaps are formed between other end 12 on all sides and inner wall surface 45, and compressed air is ejected along inner wall surface 45 from all directions of elastic body 10.

[0037] In the fluidizer 1 configured as described above, compressed air is ejected from the entire circumference of the other end 12 of the elastic body 10, causing it to flow along the inner wall surface 45 of the tank 41, thereby promoting the fluidization of the powder or granular material. Furthermore, the other end 12, which has been pushed up by the ejection of compressed air, moves to return to the inner wall surface 45, causing vibrations in the elastic body 10 itself. As a result, the ejection of compressed air and the accompanying vibrations work together to promote the fluidization of the powder or granular material, making it possible to eliminate poor outflow of the powder or granular material (clogging, blockage, bridging, rat-holing, etc.).

[0038] Next, the elastic body 10 will be described in detail.

[0039] As described above, the elastic body 10 contains stainless steel powder as an additive. Therefore, the specific gravity of the elastic body 10 is greater than that of conventional elastic bodies made solely of silicone rubber, and the elastic body 10 is also more rigid. This reduces the elastic body 10's tendency to vibrate when compressed air strikes the inner surface 13 of the elastic body 10, allowing more compressed air to accumulate in the space 2 than in the past. As a certain amount of compressed air accumulates in the space 2, the internal pressure of the space 2 increases. Therefore, the internal pressure immediately before the compressed air is ejected is greater than in the past. That is, compressed air is ejected from the space 2 when the internal pressure exceeds a predetermined value, but this predetermined value is greater than in the case where the stainless steel powder is not included. As a result, the ejection speed of the compressed air increases, and the compressed air flows more forcefully than in the past, making it easier for the powder and granular material to flow with a single ejection. Therefore, compressed air with a high jet velocity can be easily injected into powders and granules, such as those with a high specific gravity, fine powders that do not flow well, highly adhesive powders and granules, and powders and granules with a large angle of repose, making them suitable for use. Furthermore, the time required for compressed air to flow is shorter than when compressed air is continuously or intermittently sent using a conventional fluidizer that uses an elastic body that does not contain stainless steel powder, thereby efficiently promoting fluidization.

[0040] Furthermore, when compressed air is ejected, fine, high-frequency vibrations occur in the elastic body 10. Since stainless steel powder is contained in these parts, even if a part of the fluidizer is chipped during use, it can be detected by a metal detector.

[0041] Furthermore, when attempting to design an elastic body so that chipping can be detected by a metal detector, one common idea is to incorporate a small amount of iron powder, for example. However, while iron powder may be more cost-effective, iron powder is prone to rust, which creates a problem. That is, when an elastic body contains iron powder, there is a risk that rust will be mixed into the powder. Furthermore, to prevent rust, the surface of the iron powder can be plated or coated with a metal, or a rust inhibitor can be mixed into the elastic material. However, in this case, there is a risk that the plating, coating, or other chemicals will be mixed into the powder. Therefore, when used in fields such as food, stainless steel powder is preferable from a hygienic perspective.

[0042] The stainless steel powder content is preferably in the range of 30% by weight to 70% by weight, and more preferably in the range of 50% by weight to 60% by weight, based on 100% by weight of the elastomer 10. A content of 30% by weight or more allows for easy detection by a metal detector even if fragments of the elastomer 10 are mixed into the powder or granular material, making the fluidizer suitable for applications such as food. While a high content can cause the elastomer 10 to be unable to withstand vibration, a content of 70% by weight or less allows for high tear strength against the pressure of compressed air, making the elastomer 10 less likely to break even when the compressed air is ejected at an increased velocity. Furthermore, a content of 50% by weight to 60% by weight allows for the hardness of the elastomer 10 to be approximately the same as that of a conventional elastomer not containing stainless steel powder, making it easier to detect by a metal detector, and more reliably detecting even small amounts of chipped elastomer 10.

[0043] Furthermore, the maximum particle size of the stainless steel powder is preferably in the range of 20 μm to 100 μm. The maximum particle size can be determined, for example, by sieving. If the maximum particle size is too small, it is costly to produce the stainless steel powder, which is disadvantageous in terms of cost. By keeping the maximum particle size within the above range, it is possible to easily produce stainless steel powder that can be uniformly dispersed. Therefore, if the maximum particle size is within the above range, both cost and quality stability can be achieved when manufacturing a fluidization device.

[0044] As described above, the elastic material of the elastic body 10 is silicone rubber. The hardness of the elastic body 10 (durometer hardness according to JIS K6253) is preferably 40 to 80 degrees. If the hardness is too high, the tear strength decreases, making the elastic body 10 more susceptible to breakage when vibrated due to the ejection of compressed air. More specifically, the one end 11 of the elastic body 10 is directly exposed to the compressed air flowing from the nearby outlet 22, which may cause the attachment portion of the supply pipe 20 to tear and the elastic body 10 to fall off the supply pipe 20 during use. Furthermore, the other end 12 may be torn by the ejection of compressed air, and the resulting fragments may become mixed in with the powder or granular material. Therefore, if the hardness of the elastic body 10 is within the above-described range, the elastic body 10 is resistant to tearing and can maintain its attachment to the supply pipe 20 when compressed air is supplied, making it suitable for a fluidizer.

[0045] Furthermore, it is preferable that the surface of the elastic body is not plated with metal or painted with a coating agent as an additive material used therein, and that no anti-rust chemicals are mixed into the elastic material. With this configuration, no plating, coating, or anti-rust chemicals are used on the elastic body 10, making it a fluidizer suitable for use in fields such as food.

[0046] In the above embodiment, the vessel to which the fluidization device is attached is a tank having a specific shape and size, but the vessel may have other shapes. The vessel may also be a hopper or a silo.

[0047] Furthermore, in the above embodiment, the elastic material of the elastic body is silicone rubber, but other elastic materials such as fluororubber, ethylene propylene rubber (EPDM), etc. may also be used.

[0048] Furthermore, in the above embodiment, the content of stainless steel powder is set to a specific value, but it may be set to another value.

[0049] Furthermore, in the above embodiment, the hardness of the elastic body is set to a specific value, but it may be set to another value.

[0050] Furthermore, in the above embodiment, the maximum particle size of the stainless steel powder is set to a specific value, but it may be set to another value.

[0051] Furthermore, in the above embodiment, the elastic body is such that the additive material used therein is neither plated with metal nor painted with a coating agent, and no anti-rust chemicals are mixed into the elastic material. However, the additive material may be plated or painted with a coating agent, or both, or an anti-rust chemical may be mixed into the elastic material. The additive material may also be painted with another chemical. Furthermore, the additive material may be partially painted with a chemical. Furthermore, the additive material may not be painted with a chemical, but an anti-rust chemical may be mixed into the elastic material. When used in fields other than food, etc., such conditions can also be used suitably.

[0052] Furthermore, in the above embodiment, the other end is in contact with the inner wall surface over its entire circumference before compressed air is supplied, but it may be in contact with only a portion of the circumference. Alternatively, the other end may be separated from the inner wall surface, or a gap may be formed between the other end and the inner wall surface.

[0053] Furthermore, in the above embodiment, the elastic body is formed to a specific thickness, but it may be formed to a different thickness.

[0054] Furthermore, in the above embodiment, the predetermined value of the internal pressure by compressed air can be set appropriately depending on the size of the fluidizing device 1, the powder and granular material to be used, and other conditions.

[0055] Furthermore, in the above-described embodiment, the powder or granular material used is not particularly limited. [Explanation of symbols]

[0056] 1...Fluidization device 2…Space 10...Elastic body 11...One end 12...Other end 42…Side wall 44…Discharge port 45...Inner wall surface In addition, the same reference numerals in each drawing indicate the same or corresponding parts.

Claims

1. A fluidizing device attached to the inner wall surface of a side wall of a container into which powder or granular material is introduced and which has a discharge port, an elastic body having a side surface shape of a truncated cone that widens from one end to the other end, the other end of which abuts against the inner wall surface to form a space between the elastic body and the inner wall surface; a supply pipe attached to close the one end, passing through the space and penetrating the side wall, and supplying compressed air from the outside to the space, The elastic body contains stainless steel powder as an additive material, and is configured to eject the compressed air from the space to the outside of the elastic body when the internal pressure caused by the compressed air reaches a predetermined value or higher.

2. 2. The fluidizing device according to claim 1, wherein the stainless steel powder is contained in an amount of 30% by weight to 70% by weight based on 100% by weight of the elastic body.

3. the elastic material of the elastic body is made of silicone rubber, 3. The fluidizing device according to claim 1, wherein the elastic body has a hardness of 40 to 80 degrees.

4. 3. The fluidizing device according to claim 1, wherein the maximum particle size of the stainless steel powder is in the range of 20 μm to 100 μm.

5. 3. A fluidization device according to claim 1 or claim 2, wherein the surface of the elastic body is not plated with metal or painted with a coating agent on the additive material used therein, and no agent for rust prevention is mixed into the elastic material.

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