Fluidization device

Abstract

To provide a fluidizing device that can more easily fluidize powder or granular material. [SOLUTION] The fluidizing device 1 is equipped with an elastic body that is attached to the inner wall surface of a side wall of a container having a discharge port and into which powder or granular material is charged, has a side shape of a truncated cone that widens from one end to the other end, and has the other end abutting the inner wall surface to form a space between 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 an example of 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 disposed 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 disposed on the inner wall surface 58 side, and the air pulsar 53 is disposed on the outer wall surface 59 side. Then, when compressed air is intermittently injected into the air passage 54 and sent to the space 55, the pressure in the space 55 increases, and the elastic body 52 is elastically deformed in a direction to become flattened by the pressure. This deformation forms a gap between the outer periphery of the elastic body 52 and the inner wall surface 58, and the air in the space 55 is blown into the container through the gap. As a result, the powder and granular material filled in the container is fluidized by the blowing in of air, and the upper part of the discharge port solidifies in an arch shape due to the load of the powder and granular material, eliminating the state where the discharge port is blocked (powder and granular material bridge). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2003-34429 A Summary of the Invention [Problem to be solved by the invention]

[0008] However, in the conventional fluidizing devices as described above, depending on the type and amount of powder or granular material, there are cases where the powder or granular material is not fluidized, 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 port, and is equipped with an elastic body having a truncated cone side shape that spreads from one end to the other end, with the other end abutting against the inner wall surface to form a space between the inner wall surface, and a supply pipe that is attached so as to close one end, penetrates the side wall via the space, and supplies compressed air from the outside to the space, the elastic body containing stainless steel powder as an additive material, and 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. The stainless steel powder is contained in the range of 30% by weight to 70% by weight in the elastic body (100% by weight), and the maximum particle size of the stainless steel powder is in the range of 20 μm to 100 μm. This is what we have in mind.

[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 portion where fine, high-frequency vibrations occur when compressed air is ejected. Even if fragments of the elastic body are mixed into the powder, they can be easily detected by a metal detector. Furthermore, high tear strength against the pressure of compressed air can be maintained. Furthermore, stainless steel powder that can be uniformly dispersed can be easily produced.

[0014] Claim 2 The invention described is as follows: 1st article In the above-mentioned configuration of the invention, the elastic material of the elastic body is made of silicone rubber, and the hardness of the elastic body is 40 degrees to 80 degrees.

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

[0018] Claim 3 The invention described in the present application is one in which, in the configuration of the invention described in claim 1 or claim 2, the elastic body is neither plated with metal nor painted with a coating agent on its surface as an additive material used therein, and no agent for the purpose of rust prevention is mixed into the elastic material.

[0019] With this configuration, plating, coating agents, and chemicals for rust prevention are not used on the elastic body. Effect of the Invention

[0020] As explained above, in the invention described in 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 the compressed air increases and the powder and granules become easier to flow. In addition, because stainless steel powder is included 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. Even if fragments of the elastic body get mixed in with the powder, they can be easily detected by a metal detector, making this a fluidizing device suitable for the food industry. Furthermore, since it is possible to maintain high tear strength against the pressure of compressed air, the elastic body is less likely to break even if the compressed air ejection speed increases. Furthermore, since stainless steel powder that can be uniformly dispersed can be easily produced, it is possible to achieve both cost and quality stability.

[0022] Claim 2 The invention described is as follows: 1st article In addition to the effects of the invention described above, the elastic body is resistant to tearing and can maintain the attached state between the elastic body and the supply pipe when compressed air is supplied, making the elastic body suitable for use in a fluidizing device.

[0024] Claim 3 In addition to the effects of the invention described in claim 1 or 2, the invention described here does not require plating, coating agents, or anti-rust agents to be used on the elastic body, making it a fluidization device suitable for use in the food industry and other fields. [Brief description 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. [Diagram 2] 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 viewed from the inner wall surface side. [Diagram 3] FIG. 3 is a schematic cross-sectional view of line III-III of the fluidization apparatus shown in FIG. 2. [Figure 4] FIG. 2 is a schematic cross-sectional view showing a state in which the fluidization device shown in FIG. 1 is used. [Diagram 5] FIG. 1 is a schematic cross-sectional view showing a conventional fluidization device disclosed in Patent Document 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[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 for temporarily storing raw materials that opens in the vertical direction and has a funnel-shaped side wall 42. The upper side of tank 41 has raw material inlet 43, and the lower side has discharge outlet 44. Tank 41 is installed in, for example, a food factory, and discharges powdered or granular material introduced through inlet 43 from discharge outlet 44. A plurality of fluidizers 1 (1a-1c) are attached to 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 cone-like 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 in a state where the supply pipe 20 is inserted into one end 11. When viewed from the side, the elastic body 10 extends a certain distance from one end 11 along the supply pipe 20, and then extends to the other end 12, leaving the supply pipe 20 and inclining obliquely downward. With this configuration, the elastic body 10 abuts against the entire circumference of the supply pipe 20, so that the attachment state between the elastic body 10 and the supply pipe 20 is strong. In addition, the thickness of the elastic body 10 is set to gradually decrease toward the tip at the other end 12. This makes it easier for the other end 12 to vibrate with 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, and as described above, the side surface near the tip 21 and the elastic body 10 are integrated, and the supply pipe 20 extends toward the attachment target side (side wall 42 of the tank 41) on the inner surface 13 side of the elastic body 10. In addition, four exhaust ports 22 (22a to 22d) are formed at predetermined intervals in the circumferential direction on the side surface of the supply pipe 20 for flowing compressed air toward the space 2 described later. With this configuration, the compressed air flows in all directions, so that the compressed air can be uniformly distributed over the entire inner surface 13 side of the elastic body 10. In addition, a spiral groove (not shown) is formed on the side surface of the supply pipe 20 that is the supply source from the exhaust ports 22. With this configuration, the fluidization device 1 can be fixed at a predetermined position on the side wall 42 of the tank 41 by the washer 23 and the nut 24.

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

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

[0035] Referring to FIG. 4, first, a through hole (not shown) is formed in the side wall 42 of the tank 41 at a position corresponding to the mounting location of the fluidizer 1. Next, the elastic body 10 is placed on the inner wall surface 45 side of the portion where the through hole is formed, and the supply pipe 20 is inserted into the through hole. Then, the fluidizer 1 is installed so that the other end 12 of the elastic body 10 is in contact with the inner wall surface 45. Thereafter, the washer 23 and the 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 the supply pipe 20 by a timer and a solenoid valve (not shown) installed outside. Then, compressed air is supplied from the outside to the space 2 as shown by the arrows 30 and 31 in FIG. 4. When compressed air accumulates in the space 2, the compressed air tries to be ejected to the outside due to the internal pressure as shown by the arrow 32 in FIG. 4. Then, when the internal pressure reaches a predetermined value or more, the entire circumference of the other end 12 of the elastic body 10 is pushed up in a direction away from the inner wall surface 45, and the compressed air is ejected from the space 2 to the outside of the elastic body 10 as shown by the arrow 33 in FIG. 4. That is, a gap is formed between the other end 12 in all directions and the inner wall surface 45, and the compressed air is ejected along the inner wall surface 45 from all directions of the elastic body 10.

[0037] In the fluidizer 1 configured in this manner, compressed air is ejected from the entire circumference of the other end 12 of the elastic body 10 and caused to flow along the inner wall surface 45 of the tank 41, thereby promoting the fluidization of the powder or granular material. In addition, the other end 12, 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 vibrations that are generated by it 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-hole phenomenon, 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 material. Therefore, the elastic body 10 has a larger specific gravity and higher rigidity than conventional elastic bodies made of silicone rubber alone. This makes it difficult for the elastic body 10 to vibrate when compressed air hits the inner surface 13 of the elastic body 10, and more compressed air accumulates 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 higher than in the past. That is, when the internal pressure reaches a predetermined value or more, the compressed air is ejected from the space 2 to the outside of the elastic body 10, and the predetermined value is higher than in the case where stainless steel powder is not included. As a result, the ejection speed of the compressed air increases, and the compressed air flows more vigorously than in the past, making it easier for the powder to flow in one ejection. Therefore, for example, powders with a high specific gravity, fine powders that do not flow well, powders with strong adhesiveness, powders with a large angle of repose, etc. can be easily fluidized by compressed air with a high jet speed, and can be used suitably. Also, compared with the conventional fluidizing device using an elastic body that does not contain stainless steel powder, in which compressed air is sent continuously or intermittently, the time for which compressed air is sent is shortened, and fluidization can be promoted efficiently.

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

[0041] In addition, when trying to configure an elastic body so that chipping can be detected by a metal detector, it is common to think of, for example, containing a small amount of iron powder. However, while iron powder may be more advantageous in terms of cost, problems arise due to the fact that iron powder rusts easily. That is, in an elastic body containing iron powder, there is a risk that rust will get mixed into the powder. Also, for rust prevention, the surface of the iron powder can be plated with metal or painted with a coating agent, or a rust inhibitor can be mixed into the elastic material, but in that case, there is a risk that chemicals such as plating or coating agents will get mixed into the powder. Therefore, when used in fields such as food, it is preferable to use stainless steel powder from a hygienic standpoint.

[0042] The stainless steel powder is preferably contained 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 elastic body 10. By containing 30% by weight or more, even if fragments of the elastic body 10 are mixed into the powder, the elastic body 10 can be easily detected by a metal detector, making the fluidizing device suitable for the food industry. If the content is too high, the elastic body 10 may not be able to withstand vibration, but if the content is 70% by weight or less, the elastic body 10 can maintain high tear strength against the pressure of compressed air, so that the elastic body 10 is less likely to break even if the ejection speed of the compressed air increases. Furthermore, if the content is in the range of 50% by weight to 60% by weight, the hardness of the elastic body 10 can be made approximately the same as that of a conventional elastic body not containing stainless steel powder, and detection by a metal detector becomes easier, and even if the elastic body 10 is chipped, it can be detected more reliably.

[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 a measurement using a sieving method. If the maximum particle size is too small than the above numerical range, it is costly to produce the stainless steel powder, which is disadvantageous in terms of cost. By setting the maximum particle size within the above numerical range, stainless steel powder that can be uniformly dispersed can be easily produced. Therefore, if the maximum particle size is within the above numerical range, both cost and quality stability can be achieved in manufacturing the 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 degrees to 80 degrees. If the hardness is too high, the tear strength decreases, and the elastic body 10 is easily broken when vibrated with the ejection of compressed air. More specifically, the one end 11 of the elastic body 10 is directly hit by the compressed air flowing from the outlet 22 located nearby, so there is a risk that the attachment part of the supply pipe 20 will tear off with use, and the elastic body 10 will easily fall off the supply pipe 20. In addition, the other end 12 may be torn by the ejection of compressed air, and the broken pieces may be mixed into the powder and granular material. Therefore, if the hardness of the elastic body 10 is within the above numerical range, it is resistant to tearing, and the attachment state between the elastic body 10 and the supply pipe 20 can be maintained when compressed air is supplied, making it suitable for a fluidizing device.

[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 agent, or anti-rust chemicals are used on the elastic body 10, making it a fluidizing device suitable for use in fields such as food.

[0046] In the above embodiment, the vessel to which the fluidizer is attached is a tank having a specific shape and size, but the vessel may be of other shapes. Also, the vessel may be a hopper or a silo.

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

[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 one in which 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, but the additive material may be plated or painted with a coating agent, or both, and anti-rust chemicals 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 the elastic material may be mixed with an anti-rust chemical. 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 a state where the entire circumference of the other end is in contact with the inner wall surface before compressed air is supplied, but it may be in partial contact, or 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 another thickness.

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

[0055] Furthermore, in the above 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 symbols in each drawing indicate the same or corresponding parts.

Claims

1. A fluidizing device that is attached to an 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 shape of a truncated cone expanding 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 side wall via the space, 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 an internal pressure caused by the compressed air reaches or exceeds a predetermined value; The stainless steel powder is contained in a range of 30% by weight or more and 70% by weight or less based on 100% by weight of the elastic body, A fluidizing apparatus, wherein the maximum particle size of the stainless steel powder is in the range of 20 μm or more and 100 μm or less.

2. The elastic material of the elastic body is made of silicone rubber, 2. The fluidizing device according to claim 1, wherein the elastic body has a hardness of 40 degrees to 80 degrees.

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

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