JP2013121704A - Device and method for manufacturing green honeycomb formed body and method of manufacturing honeycomb fired body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing green honeycomb formed body capable of efficiently obtaining green honeycomb formed body.SOLUTION: The method for manufacturing green honeycomb formed body includes: a cooling process of, while conveying a honeycomb shaped green body 300 having a plurality of through-holes 300a by means of a roller conveyer 444, supplying cool wind CW to the through-holes 300a of the green body 300 from a blower 446 and cooling the green body 300, on a cooling part 440.

Description

  The present invention relates to a method and apparatus for manufacturing a green honeycomb molded body, and a method for manufacturing a honeycomb fired body.

  A honeycomb fired body having a plurality of through holes can be obtained by firing a green honeycomb molded body. The green honeycomb formed body is obtained, for example, by forming a raw material mixture containing a solvent to obtain an undried honeycomb-shaped green body and then drying the green body. As a method for drying a green body, for example, a method using a microwave or a heated gas is known (for example, see Patent Document 1 below). When manufacturing a green honeycomb molded body, the honeycomb-shaped green body is heated and dried to obtain a green honeycomb molded body, and then the green honeycomb molded body is cut or the through holes of the green honeycomb molded body are sealed. The green honeycomb molded body may be processed by sealing with a material.

JP-A-1-503136

  By the way, with respect to a method for manufacturing a green honeycomb molded body, it is required to efficiently obtain a green honeycomb molded body.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a method for manufacturing a green honeycomb molded body and an apparatus for manufacturing the green honeycomb molded body capable of efficiently obtaining a green honeycomb molded body. Another object of the present invention is to provide a method for manufacturing a honeycomb fired body obtained by using such a green honeycomb molded body.

  The method for manufacturing a green honeycomb molded body according to the present invention includes a cooling step of cooling the green body by supplying a coolant to the through holes of the green body while conveying the honeycomb-shaped green body having a plurality of through holes.

  When manufacturing a green honeycomb molded body, the green body may be in a high temperature state by heating the green body, and the green body may need to be cooled. In contrast, in the method for manufacturing a green honeycomb molded body according to the present invention, a green honeycomb molded body can be obtained by cooling a honeycomb-shaped green body having a plurality of through holes. And in the manufacturing method of the green honeycomb molded object concerning the present invention, cooling and conveyance of a green body are performed simultaneously by supplying a refrigerant to a penetration hole of a green body and cooling a green body while conveying a green body. be able to. Thereby, since the manufacturing process of a green honeycomb molded object can be simplified, a green honeycomb molded object can be obtained efficiently.

  Further, for the green honeycomb molded body, it is required to improve the dimensional accuracy of the green honeycomb molded body regardless of the presence or absence of the processing step. On the other hand, as a result of intensive studies, the present inventors obtained a green honeycomb molded body by heating and drying the green body, and then processing the green honeycomb molded body at a high temperature to obtain a green honeycomb molded body. It has been found that deformation and breakage may occur. In addition, the inventors of the present invention, after heating and drying the green body, naturally cooling the green body in a high temperature state to obtain a green honeycomb formed body tends to increase the time during which the green body is maintained at a high temperature state. Therefore, the present inventors have found that the green body may be deformed or damaged due to its own weight during natural cooling. Then, the inventors have found that, after the green body is heated and dried, the green body is forcibly cooled using a refrigerant, whereby deformation and breakage during cooling and processing can be suppressed. It was.

  The method for manufacturing a green honeycomb molded body according to the present invention may further include a drying step of heating and drying the green body before the cooling step. In such a manufacturing method, the green body heated in the drying process is cooled in the cooling process. Thereby, compared with the case where a green body is naturally cooled, the time for which a green body is kept at a high temperature state is shortened, and it can suppress that a green body deform | transforms or breaks by the dead weight of a green body. Further, even when the green honeycomb molded body is processed, since the green honeycomb molded body is suppressed from being processed at a high temperature, it is possible to prevent the green honeycomb molded body from being deformed or damaged. . Therefore, since deformation and breakage during cooling and processing can be suppressed, the dimensional accuracy of the green honeycomb molded body can be improved.

  The green body may be heated by microwave heating in the drying process. In this case, the dimensional accuracy of the green honeycomb molded body can be further improved.

  By the way, in the green body in a high temperature state, the temperature of the central portion of the green body tends to be maintained higher than the temperature of the outer peripheral portion. On the other hand, in the method for manufacturing a green honeycomb molded body according to the present invention, the plurality of through holes in the green body are more than the first through holes arranged in the center of the green body and the first through holes. And the temperature of the refrigerant supplied to the first through hole in the cooling step is the temperature of the refrigerant supplied to the second through hole. It may be a lower aspect. In this case, the green body can be cooled according to the temperature distribution of the green body, and the green body can be efficiently cooled to obtain a green honeycomb formed body more efficiently. Further, since the temperature in the green body can be made uniform, the dimensional accuracy of the green honeycomb molded body can be further improved.

  The method for manufacturing a honeycomb fired body according to the present invention includes a step of firing the green honeycomb formed body obtained by the method for manufacturing a green honeycomb formed body. In the method for manufacturing a honeycomb fired body according to the present invention, the honeycomb fired body can be obtained efficiently.

  An apparatus for manufacturing a green honeycomb molded body according to the present invention includes a container that stores a honeycomb-shaped green body having a plurality of through holes, a cooling unit that supplies a coolant to the through holes of the green body and cools the green body, Transporting means for transporting the green body, and the green body is cooled by the cooling means while being transported by the transporting means.

  In the green honeycomb molded body manufacturing apparatus according to the present invention, a green honeycomb molded body can be obtained by cooling the green body. In the green honeycomb molded body manufacturing apparatus according to the present invention, the green body is cooled by the cooling means while being transported by the transport means, so that the green body can be cooled and transported simultaneously. Thereby, since the manufacturing process of a green honeycomb molded object can be simplified, a green honeycomb molded object can be obtained efficiently.

  The apparatus for manufacturing a green honeycomb molded body according to the present invention further includes heating means for heating and drying the green body, and the green body is heated by the heating means and then cooled by the cooling means while being conveyed by the conveying means. May be. In such a manufacturing apparatus, after the green body is heated by the heating means, it is cooled by the cooling means while being transported by the transport means, so that the green body is in a higher temperature state than when the green body is naturally cooled. The time for which the green body is held is shortened, and deformation or breakage of the green body due to its own weight or the like can be suppressed. Further, even when the green honeycomb molded body obtained by the manufacturing apparatus is processed, since the green honeycomb molded body is suppressed from being processed at a high temperature, the green honeycomb molded body may be deformed or damaged. Can be suppressed. Therefore, since deformation and breakage during cooling and processing can be suppressed, the dimensional accuracy of the green honeycomb molded body can be improved.

  In the green honeycomb molded body manufacturing apparatus according to the present invention, in the same container, the green body may be cooled by the cooling means after being heated by the heating means.

  The heating means may be a microwave heating device that irradiates the green body with microwaves. In this case, the dimensional accuracy of the green honeycomb molded body can be further improved.

  According to the present invention, a green honeycomb molded body and a honeycomb fired body can be obtained efficiently. In addition, according to the present invention, the time required for manufacturing the green honeycomb molded body and the honeycomb fired body can be shortened.

It is a figure showing typically a green honeycomb fabrication object concerning one embodiment of the present invention. It is an II-II arrow line view of FIG. It is a figure which shows typically the green honeycomb molded object which concerns on other one Embodiment of this invention. It is the IV-IV arrow line view of FIG. It is a schematic cross section which shows the manufacturing apparatus of the green honeycomb molded object which concerns on one Embodiment of this invention. It is a schematic cross section which shows the manufacturing apparatus of the green honeycomb molded object which concerns on other one Embodiment of this invention. It is a figure which shows the measurement result of the temperature change of the molded object at the time of cooling. It is a figure which shows the measurement result of the diameter in the molded object of Experimental example 1. It is a figure which shows the measurement result of the diameter in the molded object of Experimental example 2.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. The ratio of dimensions is not limited to that shown in the drawings. Moreover, the same code | symbol is attached | subjected to the same or equivalent part, and the overlapping description is abbreviate | omitted.

<Green honeycomb molded body>
[First Embodiment]
FIG. 1 is a diagram schematically illustrating a green honeycomb molded body according to the first embodiment, and FIG. 1B is an enlarged view of a region R1 in FIG. 2 is a view taken in the direction of arrows II-II in FIG. As shown in FIGS. 1 and 2, the green honeycomb molded body 100 is a cylindrical body having a plurality of through holes 110 arranged substantially parallel to each other. The plurality of through holes 110 are partitioned by a partition wall 120 that extends substantially parallel to the central axis of the green honeycomb molded body 100. The plurality of through holes 110 have a plurality of through holes 110a and a plurality of through holes 110b adjacent to the through holes 110a. The through hole 110 a and the through hole 110 b extend substantially perpendicular to both end faces of the green honeycomb molded body 100.

  The cross section substantially perpendicular to the axial direction (longitudinal direction) of the through hole 110a and the through hole 110b has a hexagonal shape. The cross section of the through hole 110a is, for example, a regular hexagonal shape in which the lengths of the sides 140 forming the cross section are substantially equal to each other, but may be a flat hexagonal shape. The cross section of the through hole 110b is, for example, a flat hexagonal shape, but may be a regular hexagonal shape. The lengths of the sides facing each other in the cross section of the through hole 110b are substantially equal to each other. The cross-section of the through-hole 110b is divided into two (a pair) of long sides 150a having substantially the same length and four (two pairs) of short sides 150b having substantially the same length as the sides 150 forming the cross-section. ,have. The short side 150b is disposed on each side of the long side 150a. The long sides 150a face each other substantially in parallel, and the short sides 150b face each other substantially in parallel.

  The partition 120 has the partition 120a as a part which partitions the through-hole 110a and the through-hole 110b. That is, the through hole 110a and the through hole 110b are adjacent to each other through the partition wall 120a. By arranging one through hole 110b between adjacent through holes 110a, the through holes 110a are alternately arranged with the through holes 110b in the arrangement direction of the through holes 110a (a direction substantially orthogonal to the side 140). Yes.

  Each of the sides 140 of the through hole 110a faces the long side 150a of any one of the plurality of through holes 110b substantially in parallel. That is, each of the wall surfaces forming the through hole 110a is opposed substantially parallel to the one wall surface forming the through hole 110b in the partition wall 120a located between the through hole 110a and the through hole 110b. The through-hole 110 has a structural unit including one through-hole 110a and six through-holes 110b surrounding the through-hole 110a. In the structural unit, all the sides 140 of the through-hole 110a are included. It faces the long side 150a of the through hole 110b. In the green honeycomb molded body 100, at least one length of the side 140 of the through hole 110a may be substantially equal to the length of the opposing long side 150a, and each length of the side 140 is equal to that of the opposing long side 150a. It may be approximately equal to the length.

  The partition 120 has the partition 120b as a part which partitions the mutually adjacent through-holes 110b. That is, the through holes 110b surrounding the through hole 110a are adjacent to each other via the partition wall 120b.

  Each of the short sides 150b of the through holes 110b is opposed to the short sides 150b of the adjacent through holes 110b substantially in parallel. That is, the wall surfaces forming the through-holes 110b face each other substantially in parallel in the partition wall 120b located between the adjacent through-holes 110b. In the green honeycomb molded body 100, between the adjacent through holes 110b, at least one length of the short side 150b of the through hole 110b may be substantially equal to the length of the opposing short side 150b, and each of the short sides 150b. May be substantially equal to the length of the opposing short side 150b.

  The length of the green honeycomb molded body 100 in the longitudinal direction of the through holes 110a and 110b is, for example, 50 to 400 mm. The outer diameter of the green honeycomb molded body 100 is, for example, 50 to 400 mm. In the structural unit including one through hole 110a and the through hole 110b surrounding the through hole 110a, the length of the side 140 is, for example, 0.2 to 5.0 mm. In the above structural unit, the length of the long side 150a of the through hole 110b is, for example, 0.2 to 5.0 mm, and the length of the short side 150b of the through hole 110b is, for example, 0.1 to 4.5 mm. The thickness (cell wall thickness) of the partition wall 120 is, for example, 0.1 to 5.0 mm.

[Second Embodiment]
FIG. 3 is a view schematically showing a green honeycomb molded body according to the second embodiment, and FIG. 3B is an enlarged view of a region R2 in FIG. 4 is a view taken in the direction of arrows IV-IV in FIG. As shown in FIGS. 3 and 4, the green honeycomb molded body 200 is a cylindrical body having a plurality of through-holes 210 arranged substantially parallel to each other. The plurality of through holes 210 are partitioned by partition walls 220 extending substantially parallel to the central axis of the green honeycomb molded body 200. The plurality of through holes 210 have a plurality of through holes 210a and a plurality of through holes 210b adjacent to the through holes 210a. The through hole 210 a and the through hole 210 b extend substantially perpendicularly to both end faces of the green honeycomb molded body 200.

  The cross section substantially perpendicular to the axial direction (longitudinal direction) of the through hole 210a and the through hole 210b is a hexagonal shape. The cross section of the through hole 210a is, for example, a regular hexagonal shape in which the lengths of the sides 240 forming the cross section are substantially equal to each other, but may be a flat hexagonal shape. The cross section of the through hole 210b is, for example, a flat hexagonal shape, but may be a regular hexagonal shape. The lengths of the sides facing each other in the cross section of the through hole 210b are different from each other. The cross section of the through-hole 210b has three long sides 250a having substantially the same length and three short sides 250b having substantially the same length as the sides 250 forming the cross section. The long side 250a and the short side 250b face each other substantially in parallel, and the short side 250b is disposed on each side of the long side 250a.

  The partition 220 has the partition 220a as a part which partitions the through-hole 210a and the through-hole 210b. That is, the through hole 210a and the through hole 210b are adjacent to each other through the partition wall 220a. Between the adjacent through-holes 210a, two through-holes 210b adjacent to each other in a direction substantially orthogonal to the arrangement direction of the through-holes 210a are arranged, and the two adjacent through-holes 210b are adjacent to each other. They are arranged symmetrically across a line connecting the centers of the sections of 210a.

  Each of the sides 240 of the through-hole 210a is opposed to the long side 250a of any one of the plurality of through-holes 210b substantially in parallel. That is, each of the wall surfaces forming the through hole 210a is opposed to the one wall surface forming the through hole 210b substantially in parallel in the partition wall 220a located between the through hole 210a and the through hole 210b. The through-hole 210 has a structural unit including one through-hole 210a and six through-holes 210b surrounding the through-hole 210a. In the structural unit, all the sides 240 of the through-hole 210a are included. It faces the long side 250a of the through hole 210b. Each vertex of the cross section of the through hole 210a is opposed to the vertex of the adjacent through hole 210a in the arrangement direction of the through holes 210a. In the green honeycomb molded body 200, at least one length of the side 240 of the through hole 210a may be substantially equal to the length of the opposing long side 250a, and each length of the side 240 is equal to that of the opposing long side 250a. It may be approximately equal to the length.

  The partition 220 has the partition 220b as a part which partitions the mutually adjacent through-holes 210b. That is, the through holes 210b surrounding the through hole 210a are adjacent to each other through the partition 220b.

  Each of the short sides 250b of the through holes 210b is opposed to the short sides 250b of the adjacent through holes 210b substantially in parallel. That is, the wall surfaces forming the through-holes 210b face each other substantially in parallel in the partition 220b positioned between the adjacent through-holes 210b. One through hole 210b is surrounded by three through holes 210a. In the green honeycomb molded body 200, at least one length of the short side 250b of the through hole 210b may be substantially equal to the length of the opposing short side 250b between the adjacent through holes 210b. May be substantially equal to the length of the opposing short side 250b.

  The length of the green honeycomb molded body 200 in the longitudinal direction of the through holes 210a and 210b is, for example, 50 to 400 mm. The outer diameter of the green honeycomb molded body 200 is, for example, 50 to 400 mm. In a structural unit including one through hole 210a and a through hole 210b surrounding the through hole 210a, the length of the side 240 is, for example, 0.2 to 5.0 mm. In the above structural unit, the length of the long side 250a of the through hole 210b is 0.2 to 5.0 mm, for example, and the length of the short side 250b of the through hole 210b is 0.1 to 4.5 mm, for example. The partition wall 220 has a thickness (cell wall thickness) of, for example, 0.1 to 5.0 mm.

  The material of the green honeycomb molded bodies 100 and 200 is not particularly limited. The green honeycomb molded bodies 100 and 200 include, for example, an inorganic compound powder that becomes ceramics when fired, and may further include an organic binder and additives as necessary. Examples of ceramics include alumina, silica, mullite, cordierite, glass and oxides such as aluminum titanate; silicon carbide; silicon nitride. The aluminum titanate can contain magnesium and / or silicon.

  For example, when obtaining a honeycomb fired body of aluminum titanate, the inorganic compound powder includes an aluminum source powder such as α-alumina powder, and a titanium source powder such as anatase-type or rutile-type titania powder. A magnesium source powder such as magnesia powder and magnesia spinel powder and / or a silicon source powder such as silicon oxide powder and glass frit can be further included.

  Examples of the organic binder include celluloses such as methylcellulose, carboxymethylcellulose, hydroxyalkylmethylcellulose, and sodium carboxymethylcellulose; alcohols such as polyvinyl alcohol; and lignin sulfonate. The addition amount of the organic binder is, for example, 0.1 to 20 parts by mass with respect to 100 parts by mass of the inorganic compound powder.

  Examples of the additive include a pore-forming agent, a lubricant, a plasticizer, a dispersant, and a solvent.

  Examples of the pore-forming agent include carbon materials such as graphite; resins such as polyethylene, polypropylene, and polymethyl methacrylate; plant materials such as starch, nut shells, walnut shells, and corn; ice; dry ice. The amount of pore-forming agent added is, for example, 0 to 40 parts by mass with respect to 100 parts by mass of the inorganic compound powder.

  Examples of the lubricant include alcohols such as glycerin; higher fatty acids such as caprylic acid, lauric acid, palmitic acid, arachidic acid, oleic acid and stearic acid; and stearic acid metal salts such as Al stearate. The addition amount of the lubricant is, for example, 0 to 10 parts by mass with respect to 100 parts by mass of the inorganic compound powder.

  As a plasticizer, polyoxyalkylene alkyl ether is mentioned, for example. Examples of commercially available products include “Unilube 50MB-72” manufactured by NOF Corporation (polyoxyethylene polyoxypropylene butyl ether, viscosity at 20 ° C. of 1020 mPa · s), “UNILUBE 50MB-168” manufactured by NOF Corporation (poly Oxyethylene polyoxypropylene butyl ether and a viscosity at 20 ° C. of 2880 mPa · s). The addition amount of a plasticizer is 0.1-20 mass parts with respect to 100 mass parts of inorganic compound powder, for example.

  Examples of the dispersant include inorganic acids such as nitric acid, hydrochloric acid, and sulfuric acid; organic acids such as oxalic acid, citric acid, acetic acid, malic acid, and lactic acid; and surfactants such as ammonium polycarboxylate. The addition amount of a dispersing agent is 0-20 mass parts with respect to 100 mass parts of inorganic compound powder, for example.

  Examples of the solvent include alcohols such as methanol, ethanol, propanol and butanol; glycols such as propylene glycol, polypropylene glycol and ethylene glycol; water and the like. Among these, water is preferable, and ion-exchanged water is more preferable in terms of few impurities. The addition amount of a solvent is 10-100 mass parts with respect to 100 mass parts of inorganic compound powder, for example.

  The green honeycomb molded body is not necessarily limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, the shape of the green honeycomb molded body is not particularly limited, and can be any shape depending on the application. For example, the cross section of the through hole substantially perpendicular to the axial direction (longitudinal direction) of the through hole is not limited to a hexagonal shape, and may be a rectangular shape, an octagonal shape, a triangular shape, a circular shape, an elliptical shape, or the like. Good. Moreover, in the through hole, those having different diameters may be mixed, and those having different cross-sectional shapes may be mixed. The arrangement of the through holes is not particularly limited, and the arrangement of the central axes of the through holes is a square arrangement arranged at the apex of the square, an equilateral triangle arrangement arranged at the apex of the equilateral triangle, and a staggered arrangement Etc. Furthermore, the green honeycomb molded body is not limited to a cylindrical body, and may be an elliptical column, a triangular column, a quadrangular column, a hexagonal column, an octagonal column, or the like.

<Green honeycomb molded body manufacturing equipment>
FIG. 5 is a schematic cross-sectional view showing an apparatus for manufacturing a green honeycomb molded body according to the first embodiment. In the green honeycomb molded body manufacturing apparatus 400 shown in FIG. 5, an undried green body 300 obtained by molding a raw material mixture containing a solvent is dried and then cooled to obtain green honeycomb molded bodies 100 and 200. The green body 300 has a honeycomb shape like the green honeycomb molded bodies 100 and 200, and has a plurality of through holes 300a. The through hole 300a is partitioned by a partition wall 300b.

  The manufacturing apparatus 400 includes a drying unit 420 and a cooling unit 440. In the manufacturing apparatus 400, the green body 300 is dried and cooled in different containers. The drying unit 420 and the cooling unit 440 are adjacent to each other, and the green body 300 is continuously dried and cooled. In the manufacturing apparatus 400, for example, the green body 300 is dried and cooled while the green body 300 is conveyed.

  The drying unit 420 includes a container 422 that houses the green body 300, a roller conveyor (conveying means) 424 that conveys the green body 300, a microwave heating device (heating means) 426 that supplies the microwave M into the container 422, and A blower (heating means) 428 for supplying hot air (heat medium) HW into the container 422 and a steam supply device 430 for supplying water vapor into the container 422 are provided.

  The container 422 contains a roller conveyor 424, a microwave heating device 426, and a blower 428. The container 422 is made of, for example, a metal such as stainless steel from the viewpoint of shielding microwaves. An introduction pipe 432 for supplying water vapor from the water vapor supply device 430 is connected to the bottom surface of the container 422. A discharge pipe 434 for discharging the atmospheric gas in the container 422 to the outside is connected to the upper surface of the container 422.

  The roller conveyor 424 is disposed in the lower part in the container 422. The roller conveyor 424 has a plurality of rollers 424a arranged in the transport direction (for example, the horizontal direction) D1. The roller 424a is, for example, a long roller extending in a direction D3 perpendicular to the transport direction D1 and the vertical direction D2. For example, the roller conveyor 424 conveys the green body 300 placed on the placing table 310 in the carrying direction D1. The green body 300 is conveyed by the roller conveyor 424 in a state where the through hole 300a extends in the vertical direction D2.

  The mounting table 310 is made of ceramics, for example. One green body 300 may be mounted on the mounting table 310, or a plurality of green bodies 300 may be mounted. A ventilation hole is formed in the mounting table 310, and hot air HW supplied from the blower 428 and cold air CW supplied from the blower 446 described later pass through the ventilation hole and enter the through hole 300 a of the green body 300. Supplied. Moreover, the supply efficiency of the hot air HW and the cold air CW can be adjusted by adjusting the number and positions of the ventilation holes in the mounting table 310. Furthermore, the hot air HW and the cold air CW can be efficiently supplied to the green body 300 by shielding the area where the green body 300 is not disposed between the mounting tables 310 with a shielding plate or the like.

  The microwave heating device 426 is disposed on the upper surface of the container 422 in the container 422 and extends along the transport direction D1. The microwave heating device 426 irradiates the green body 300 with the microwave M, thereby heating the green body 300 by microwaves and drying it. The wavelength of the microwave M is not particularly limited as long as the green body 300 can be heated, and is, for example, 0.3 to 3 GHz. Although the output of the microwave M is not specifically limited, For example, it is 0.1-50 kW.

The blower 428 is disposed on the bottom surface of the container 422 and extends along the transport direction D1. The blower 428 is, for example, a hot air supply device. The blower 428 supplies hot air HW to the through hole 300a of the green body 300, and heats the green body 300 to dry it. For example, the blower 428 supplies the hot air HW along the axial direction of the through hole 300a, and supplies the hot air HW in the vertical direction D2 when the through hole 300a extends in the vertical direction D2. The hot air HW is, for example, air. The supply amount of hot air HW is preferably ^{1~50m 3 / min, 1~20m 3 /} min is more preferred. The temperature of the hot air HW is preferably 30 to 150 ° C, more preferably 40 to 120 ° C.

The water vapor supply device 430 is disposed outside the container 422 and is connected to the container 422 via the introduction pipe 432. The water vapor supply device 430 can supply water vapor into the container 422 and maintain the surroundings of the green body 300 in an atmosphere in which water vapor exists. Although the supply conditions of water vapor | steam are not specifically limited, The temperature of water vapor | steam is 80-120 degreeC, for example, and the supply amount of water vapor | steam is 0.1-5 m < ³ > / min, for example.

  The cooling unit 440 includes a container 442 that houses the green body 300, a roller conveyor (conveying means) 444 that conveys the green body 300, a blower (cooling means) 446 that supplies cold air (refrigerant) CW into the container 442, It has.

  The container 442 is connected to the container 422 and accommodates the roller conveyor 444 and the blower 446. The container 442 is made of a metal such as stainless steel, for example.

  The roller conveyor 444 is disposed in the lower part of the container 442 and is disposed so as to be continuous with the roller conveyor 424. The roller conveyor 444 has a plurality of rollers 444a arranged in the transport direction D1. The roller 444a is, for example, a long roller extending in the direction D3. The roller conveyor 444 conveys the green body 300 placed on the placing table 310 in the carrying direction D1. For example, the green body 300 is conveyed by the roller conveyor 444 in a state in which the through hole 300a extends in the vertical direction D2.

The blower 446 is disposed on the bottom surface of the container 442 and extends along the transport direction D1. The blower 446 is, for example, a cold air supply device. The blower 446 supplies the cold air CW to the through hole 300 a of the green body 300 and cools the green body 300. For example, the blower 446 supplies the cold air CW along the axial direction of the through hole 300a, and supplies the cold air CW in the vertical direction D2 when the through hole 300a extends in the vertical direction D2. The cold air CW is air, for example. The supply amount of the cold air CW is preferably ^{1~50m 3 / min, 1~30m 3 /} min is more preferred. 10-40 degreeC is preferable and the temperature of the cold wind CW has more preferable 10-25 degreeC.

  FIG. 6 is a schematic cross-sectional view showing an apparatus for manufacturing a green honeycomb molded body according to the second embodiment. In the green honeycomb molded body manufacturing apparatus 500 shown in FIG. 6, as in the manufacturing apparatus 400, the green body 300 is dried and then cooled to obtain the green honeycomb molded bodies 100 and 200. In the manufacturing apparatus 500, the green body 300 is dried and cooled in the same container. In the manufacturing apparatus 500, for example, the green body 300 is cooled while the green body 300 is conveyed.

  The manufacturing apparatus 500 includes a container 502 that accommodates the green body 300, a roller conveyor (conveying means) 504 that conveys the green body 300, and a microwave heating apparatus (heating means) 506 that supplies the microwave M into the container 502. A blower (cooling means) 508 that supplies cold air (refrigerant) CW into the container 502 and a water vapor supply device 510 that supplies water vapor into the container 502 are provided. In the manufacturing apparatus 500, the drying unit 420 of the manufacturing apparatus 400 includes a blower 446 instead of the blower 428.

  The container 502 contains a roller conveyor 504, a microwave heating device 506, and a blower 508. The container 502 is made of, for example, a metal such as stainless steel from the viewpoint of shielding microwaves. An introduction pipe 512 for supplying water vapor from the water vapor supply device 510 is connected to the bottom surface of the container 502. A discharge pipe 514 for discharging the atmospheric gas in the container 502 to the outside is connected to the upper surface of the container 502.

  As the roller conveyor 504, the microwave heating device 506, the blower 508, and the steam supply device 510, the roller conveyor 424, the microwave heating device 426, the blower 446, and the steam supply device 430 of the manufacturing apparatus 400 can be used, respectively. The roller conveyor 504 has a plurality of rollers 504a arranged in the transport direction D1. In addition, as drying conditions and cooling conditions in the manufacturing apparatus 500, the same conditions as in the manufacturing apparatus 400 can be employed.

  In addition, in the manufacturing apparatuses 400 and 500, the supply method of the green body 300 may be a batch type in which a plurality of green bodies are conveyed at once, or a single wafer type in which a single green body is sequentially conveyed. May be. The green body 300 may be transported continuously by performing a transport operation continuously, or may be transported intermittently by performing a transport operation intermittently.

  In the manufacturing apparatus 400, the green body 300 can be cooled by supplying the cold air CW to the through hole 300a of the green body 300 by the blower 446 while the green body 300 is conveyed by the roller conveyor 444 in the cooling unit 440. Further, in the manufacturing apparatus 500, the green body 300 can be cooled by supplying the cold air CW to the through hole 300a of the green body 300 by the blower 508 while the green body 300 is being transported by the roller conveyor 504. In such manufacturing apparatuses 400 and 500, the green body 300 can be cooled and transported simultaneously. In this case, since the manufacturing process of the green honeycomb molded body can be simplified, the green honeycomb molded body can be obtained efficiently.

  Further, in the manufacturing apparatuses 400 and 500, the time required for cooling the green body 300 can be shortened by forcibly cooling the green body 300 as compared with the case where the green body 300 is naturally cooled. Thereby, the time which manufactures the green honeycomb molded object 100,200 can also be shortened.

  Furthermore, in the manufacturing apparatus 400, after the green body 300 is heated and dried by the microwave heating device 426 and the blower 428 in the drying unit 420, in the cooling unit 440, the cold air CW is supplied to the through holes 300a of the green body 300 by the blower 446. Can be supplied to cool the green body 300. Further, in the manufacturing apparatus 500, after the green body 300 is heated and dried by the microwave heating apparatus 506, the green body 300 can be cooled by supplying the cold air CW to the through holes 300a of the green body 300 by the blower 508. . In such manufacturing apparatuses 400 and 500, the time during which the green body 300 is kept at a high temperature is shortened compared to the case where the green body 300 is naturally cooled, and the green body 300 is deformed by its own weight or the like. The occurrence of breakage can be suppressed. Further, in the manufacturing apparatuses 400 and 500, even when the green honeycomb molded bodies 100 and 200 obtained by the manufacturing apparatus are processed, the green honeycomb molded bodies 100 and 200 are suppressed from being processed in a high temperature state. Therefore, deformation and breakage of the green honeycomb molded bodies 100 and 200 can be suppressed. Therefore, since the manufacturing apparatuses 400 and 500 can suppress deformation and breakage during cooling and processing, the dimensional accuracy of the green honeycomb molded bodies 100 and 200 can be improved.

  Moreover, in the manufacturing apparatuses 400 and 500, since the manufacturing apparatuses 400 and 500 are provided with the water vapor supply devices 430 and 510, the green body 300 is heated while maintaining the atmosphere around the green body 300 in the presence of water vapor. be able to. Thereby, since it is suppressed that the outer peripheral part of the green body 300 dries too much rather than a center part, the nonuniformity of a drying speed can be reduced and the deformation | transformation and damage of the green body 300 accompanying drying can be suppressed. Therefore, the dimensional accuracy of the green honeycomb molded bodies 100 and 200 can be further improved.

  In addition, the structure of the manufacturing apparatus of the green honeycomb molded object is not restricted to the structure of the manufacturing apparatuses 400 and 500. For example, the manufacturing apparatus 400 may include only one of the microwave heating device 426 and the blower 428. Further, the manufacturing apparatus 500 may include a blower that supplies hot air instead of the microwave heating apparatus 506. As the heating means, a far-infrared heater or the like can be used instead of a microwave heating device or a blower that supplies hot air. The manufacturing apparatuses 400 and 500 may not include the water vapor supply apparatuses 430 and 510.

  Moreover, as a cooling means, it can replace with the air blowers 446 and 508 which supply cold air, and a refrigeration apparatus etc. can be used. The cooling unit may move in the transport direction D1 following the transport of the green body 300 in the transport direction D1. The refrigerant may be supplied continuously or intermittently. For example, the refrigerant may be injected from the refrigerant supply port only when the green body 300 passes through the vicinity of the refrigerant supply port of the cooling means. Further, the cooling means may further have a function of heating the green body 300 in addition to the function of cooling the green body 300.

  Further, the arrangement positions of the constituent members of the manufacturing apparatuses 400 and 500 are not limited to the above arrangement positions. For example, the heating means and the cooling means may be disposed only on one of the top and bottom surfaces of the containers 422 and 502, or may be disposed on both the top and bottom surfaces.

  Further, the green body 300 may be transported in a state of being in direct contact with the roller conveyors 424, 444, and 504 without being placed on the placing table 310. Moreover, the conveyance means of the green body 300 should just be able to convey the green body 300 in the conveyance direction D1, and may be a wheel conveyor by which the roller wheel which rotationally drives is arranged along the conveyance direction D1. . In this case, a plurality of wheel groups in which the wheels are arranged in a line along the conveyance direction D1 may be arranged in the direction D3, or the wheels may be arranged in a staggered manner along the conveyance direction D1. A pair of wheels in which the wheels are arranged in a line along the conveyance direction D1 may be arranged separately from each other in the direction D3 so as to support the edge of the green body 300 or the mounting table 310. . In this case, the refrigerant can be efficiently supplied to the green body 300. Furthermore, a mesh belt, a belt conveyor, or an arm that holds the green body 300 may be used as the conveying means.

<Method for producing green honeycomb molded body>
The method for manufacturing a green honeycomb molded body according to the present embodiment includes, for example, a forming process, a drying process, and a cooling process in this order. In the drying step and the cooling step, the green honeycomb molded body manufacturing apparatus 400, 500 can be used.

  In the molding step, for example, the green body 300 is obtained by the following procedure. First, an inorganic compound powder and a solvent, and an organic binder and additives added as necessary are prepared. Next, after mixing these with a kneader etc. and obtaining a raw material mixture, a raw material mixture is extruded from the extruder which has an exit opening corresponding to the cross-sectional shape of the partition of a green body, and a molded object is obtained. And an undried green body 300 is obtained by cutting the molded body into a desired length.

  In the drying process, the green body 300 obtained in the molding process is heated and dried. In the cooling process, the green body 300 is cooled by supplying the coolant to the through holes 300a of the green body 300 while transporting the green body 300 heated in the drying process. Hereinafter, the case of using the manufacturing apparatuses 400 and 500 will be described for the drying process and the cooling process, respectively. In addition, as the drying conditions in the drying process and the cooling conditions in the cooling process, the conditions described above with respect to the manufacturing apparatuses 400 and 500 can be employed.

  First, the case where the manufacturing apparatus 400 is used will be described. In the manufacturing apparatus 400, the drying process is performed in the drying unit 420. In the drying process, first, the green body 300 is placed on the roller conveyor 424 in the container 422 to which water vapor is supplied from the water vapor supply device 430. For example, the green body 300 is placed such that the through hole 300a extends in the vertical direction D2.

  Next, the green body 300 is heated and dried while the green body 300 is transported in the transport direction D1 as the roller 424a is driven to rotate. In the manufacturing apparatus 400, the green body 300 is irradiated to the green body 300 from the microwave heating device 426 while the green body 300 is transported in the transport direction D1, and the green body 300 is heated by the microwave. The green body 300 is heated by supplying hot air HW to the through hole 300a. As a result, the green body 300 is heated to remove at least a part of the liquid component (for example, solvent) in the green body 300 and the green body 300 is dried. The hot air HW is supplied to the through hole 300a from the bottom surface side of the green body 300, for example. The green body 300 heated in the drying process is conveyed to the container 442 of the cooling unit 440 by the roller conveyor 424.

  The cooling process is performed in the cooling unit 440. In the cooling step, the green body 300 is supplied to the through hole 300a of the green body 300 from the blower 446 to cool the green body 300 while the green body 300 is transported in the transport direction D1 as the rollers 444a of the roller conveyor 444 are driven to rotate. . The cold air CW is supplied from the bottom surface side of the green body 300 to the through hole 300a, for example. The green body 300 is cooled to, for example, 35 ° C. or less as a temperature that can further suppress deformation and breakage. Thus, green honeycomb molded bodies 100 and 200 are obtained.

  Next, a case where the manufacturing apparatus 500 is used will be described. In the manufacturing apparatus 500, a drying process and a cooling process are performed in the container 502.

  In the drying step, first, a plurality of green bodies 300 are conveyed by the roller conveyor 504 in the container 502 to which water vapor is supplied from the water vapor supply device 510, and the green bodies 300 are accommodated in the container 502. For example, the green body 300 is conveyed in a state in which the through hole 300a extends in the vertical direction D2. After the green body 300 to be dried and cooled is accommodated in the container 502, the operation of the roller conveyor 504 is stopped.

  Next, in a state where the green body 300 is allowed to stand, the green body 300 is heated by irradiating the green body 300 with the microwave M from the microwave heating device 506 and performing microwave heating. As a result, the green body 300 is heated to remove at least a part of the liquid component (for example, solvent) in the green body 300 and the green body 300 is dried.

  Subsequently, after the irradiation of the microwave M and the supply of water vapor from the water vapor supply device 510 are stopped, the roller conveyor 504 is operated. Then, the green body 300 is cooled by supplying the cold air CW from the blower 508 to the through hole 300a of the green body 300 while the green body 300 is being transported in the transport direction D1 as the rollers 504a of the roller conveyor 504 are driven to rotate. The cold air CW is supplied from the bottom surface side of the green body 300 to the through hole 300a, for example. The green body 300 is cooled to, for example, 35 ° C. or less as a temperature that can further suppress deformation and breakage. Thus, green honeycomb molded bodies 100 and 200 are obtained.

  In the drying process using the manufacturing apparatuses 400 and 500, the heating temperature of the green body 300 is preferably 70 ° C or higher, more preferably 80 to 95 ° C, and still more preferably 85 to 95 ° C. The drying time is, for example, 1 to 10 minutes per one green body 300. It is preferable that both the central part and the outer peripheral part of the green body 300 are heated to the above range. The green body 300 may be irradiated with the microwave M while keeping the output constant, or may be irradiated with the microwave M continuously or in multiple stages.

  A through hole 300a of the green body 300 includes a first through hole disposed at the center of the green body 300, and a second through hole disposed on the outer peripheral side of the green body 300 relative to the first through hole. In the cooling process using the manufacturing apparatuses 400 and 500, the temperature of the refrigerant supplied to the first through hole is adjusted to be lower than the temperature of the refrigerant supplied to the second through hole. May be. For example, the temperature of the refrigerant may change concentrically from the first through hole toward the outer peripheral side of the green body 300.

  In the drying process, the green body 300 may be heated and dried while the green body 300 is stationary, or the green body 300 may be heated and dried while the green body 300 is conveyed.

  In addition, the method for manufacturing the green honeycomb molded body includes cutting the green honeycomb molded bodies 100 and 200 after the cooling step, sealing the through holes of the green honeycomb molded bodies 100 and 200 with a sealing material, and the like. You may further provide the process process which processes a green honeycomb molded object. In this embodiment, since the green honeycomb molded bodies 100 and 200 are obtained through the cooling process, the green honeycomb molded bodies 100 and 200 can be prevented from being deformed or damaged in the processing process.

  In the manufacturing method of the green honeycomb molded body, the green body 300 is cooled and conveyed simultaneously by supplying the cold air CW to the through holes 300a of the green body 300 and cooling the green body 300 while conveying the green body 300. It can be carried out. Thereby, since the manufacturing process of the green honeycomb molded bodies 100 and 200 can be simplified, the green honeycomb molded bodies 100 and 200 can be obtained efficiently.

  In the method for manufacturing the green honeycomb molded body, the time required for cooling the green body 300 can be shortened by forcibly cooling the green body 300 as compared with the case where the green body 300 is naturally cooled. Thereby, the time which manufactures the green honeycomb molded object 100,200 can also be shortened.

  Furthermore, the method for manufacturing the green honeycomb molded body includes a cooling step of cooling the green body 300 by supplying cold air CW to the through holes 300a of the green body 300 after the drying step, and the green honeycomb body is heated in the drying step. The green body 300 is cooled in the cooling process. As a result, the time during which the green body 300 is kept at a high temperature is shortened as compared with the case where the green body 300 is naturally cooled, and deformation or breakage of the green body 300 due to its own weight or the like is suppressed. be able to. Further, even when the green honeycomb molded bodies 100 and 200 are processed, since the green honeycomb molded bodies 100 and 200 are suppressed from being processed in a high temperature state, the green honeycomb molded bodies 100 and 200 are deformed or damaged. Can be prevented from occurring. Therefore, since deformation and breakage during cooling and processing can be suppressed, the dimensional accuracy of the green honeycomb molded bodies 100 and 200 can be improved.

  Further, by heating the green body 300 while maintaining the surroundings of the green body 300 in an atmosphere in which water vapor exists by the steam supply devices 430 and 510, the outer peripheral portion of the green body 300 is dried more excessively than the center portion. Is suppressed. Thereby, the nonuniformity of a drying rate can be reduced and the deformation | transformation and damage of the green body 300 accompanying drying can be suppressed. Therefore, the dimensional accuracy of the green honeycomb molded bodies 100 and 200 can be further improved.

<Method for manufacturing honeycomb fired body>
The method for manufacturing a honeycomb fired body according to the present embodiment includes a firing step of firing the green honeycomb formed bodies 100 and 200 obtained by the method for manufacturing the green honeycomb formed body to obtain the honeycomb fired body. The firing temperature is, for example, 1200 to 1800 ° C. Thereby, a honeycomb fired body having substantially the same shape as the green honeycomb molded bodies 100 and 200 is obtained.

[Experimental example]
Hereinafter, experimental examples show that deformation and breakage of a molded body can be suppressed by forcibly cooling the green body after heating and drying the green body.

<Preparation of raw material mixture>
A raw material mixture containing Al ₂ O ₃ powder, TiO ₂ powder, MgO powder, SiO ₂ powder, pore former, organic binder, plasticizer, lubricant and water was prepared. The content of each component in the raw material mixture is as follows.
[Components of raw material mixture]
Al ₂ O ₃ powder: 28.2 parts by mass TiO ₂ powder: 27.9 parts by mass MgO powder: 1.5 parts by mass SiO ₂ powder: 2.3 parts by mass Pore forming agent: potato starch, 9.1 parts by mass Organic Binder: Methylcellulose, 5.9 parts by mass Plasticizer: Polyoxyethylene polyoxypropylene butyl ether, 3.5 parts by mass Lubricant: Glycerin, 0.3 parts by mass Water: 21.3 parts by mass

  The above raw material mixture was kneaded and then extrusion molded to produce a molded body A (cell density: 320 cpsi, cell wall thickness: 0.335 mm) having the same honeycomb structure as that shown in FIGS. The compact A was a cylindrical body having a length of 240 mm, and had a large number of through-holes (cross-sectional shape: hexagonal shape) extending in the longitudinal direction. The length of one side of the through hole having a regular hexagonal cross section was 0.84 mm. The length of the long side in the through hole having a flat hexagonal cross section was 0.84 mm, and the length of the short side was 0.71 mm.

Subsequently, after the molded body A was placed on the cradle so that the through holes extended in the vertical direction, the molded body A was heated and dried in a state where the molded body A was left stationary. While the molded body A is irradiated with microwaves to heat the molded body A, hot air (air, 40 ° C., 4 m ³ / min) is supplied from the bottom surface side of the molded body A to the through holes. Heated. Microwave irradiation was performed at a frequency of 2.45 GHz in the order of 7.3 minutes at 24 kW, 7.3 minutes at 16.4 kW, and 1 minute at 9.6 kW. The drying time was 1.2 minutes per molded body A. By heating the compact A, the central part of the compact A was heated to 95 ° C., and the outer peripheral part was heated to 90 ° C. In addition, the position of 120 mm from the upper end surface of the molded body A on the central axis of the molded body A is adopted as the “center part”, and the outer periphery of the molded body A in the plane of 120 mm from the upper end surface A position of 10 mm toward the center was adopted.

<Experimental example 1>
Cold air (air, 23 ° C., 1.11 m ³ / min) was supplied from the bottom side of the dried molded body A to the through holes to cool the molded body A. FIG. 7 shows the result of measuring the temperature change during cooling of the central portion and the outer peripheral portion. It was confirmed that the temperature of the center portion was higher than the temperature of the outer peripheral portion. It was confirmed that the temperature at the center was sufficiently cooled in about 5 minutes and reached 35 ° C. No deformation or breakage was observed inside the green honeycomb molded body obtained by cooling the molded body A.

<Experimental example 2>
The dried molded product A was naturally cooled. When the temperature change of the said center part and an outer peripheral part was measured, it was confirmed that it takes 90 minutes until the temperature of a center part reaches 35 degreeC.

<Dimensional accuracy measurement>
Each of the green honeycomb molded bodies obtained by cooling the molded bodies A of Experimental Example 1 and Experimental Example 2 was cut to obtain a honeycomb-shaped molded body B having a length of 169 mm. About the obtained molded object B, the average diameter, squareness, roundness, and cylindricity were measured as dimensional accuracy. Each measurement item is shown below.

(Average diameter)
The length of the diameter passing through the center of the surface in the measurement heights of 2 mm, 21 mm, 39 mm, 57 mm, 76 mm, 94 mm, 112 mm, 130 mm, 149 mm and 167 mm in the longitudinal direction from one end surface of the molded body B Was measured in the circumferential direction (0 to 360 °). Moreover, the average diameter in the surface of each measurement height was measured. The measurement result of the molded product B of Experimental Example 1 is shown in FIG. 8, and the measurement result of the molded product B of Experimental Example 2 is shown in FIG. Fig.8 (a) and FIG.9 (a) are the measurement results of the diameter of the circumferential direction in each measurement height. FIG. 8B and FIG. 9B are measurement results of the average diameter in the plane of each measurement height. When the average value of the average diameters in the plane of each measurement height was calculated, it was 157.1424 mm in Experimental Example 1 and 157.3208 mm in Experimental Example 2, and both were equivalent.

(right angle)
The “squareness” is a value defined by JIS B 0021. When the molded body B is not distorted and the longitudinal direction of the molded body B is perpendicular to the bottom surface of the molded body B, the perpendicularity is 0 mm. The perpendicularity of the molded body B of Experimental Example 1 was 1.49 mm, and the perpendicularity of the molded body B of Experimental Example 2 was 2.25 mm. In Experimental Example 1, it was confirmed that the dimensional accuracy was higher than in Experimental Example 2.

(Roundness)
The roundness of the upper surface of the molded body B was measured. The roundness of Experimental Example 1 was 1.05 mm, the roundness of Experimental Example 2 was 1.08 mm, and both were equivalent.

(Cylindrical degree)
The “cylindricity” is a value defined by JIS B 0021. When the molded body B is not distorted, the cylindricity is 0 mm. The cylindricity of Experimental Example 1 was 2.21335 mm, and the cylindricity of Experimental Example 2 was 2.74405 mm. In Experimental Example 1, it was confirmed that the dimensional accuracy was higher than in Experimental Example 2.

  From the result of the dimensional accuracy measurement, it was confirmed that the experimental example 1 had higher dimensional accuracy than the experimental example 2.

  DESCRIPTION OF SYMBOLS 100,200 ... Green honeycomb molded object, 300 ... Green body, 300a ... Through-hole, 400,500 ... Green honeycomb molded object manufacturing apparatus, 422, 442, 502 ... Container, 426, 506 ... Microwave heating apparatus (heating means) , 428 ... Blower (heating means), 444, 504 ... Roller conveyor (conveying means), 446, 508 ... Blower (cooling means), CW ... Cold air (refrigerant).

Claims (9)

  A method for manufacturing a green honeycomb molded body, comprising: a cooling step of cooling the green body by supplying a coolant to the through holes of the green body while conveying a honeycomb-shaped green body having a plurality of through holes.   The manufacturing method according to claim 1, further comprising a drying step of heating and drying the green body before the cooling step.   The manufacturing method according to claim 2, wherein the green body is heated by microwave heating in the drying step. The plurality of through-holes are a first through-hole disposed at the center of the green body, and a second through-hole disposed on the outer peripheral side of the green body with respect to the first through-hole. Have
The said cooling process WHEREIN: The temperature of the refrigerant | coolant supplied to a said 1st through-hole is lower than the temperature of the refrigerant | coolant supplied to a said 2nd through-hole. Production method.   A method for manufacturing a honeycomb fired body, comprising a step of firing the green honeycomb molded body obtained by the manufacturing method according to any one of claims 1 to 4. A container containing a honeycomb-shaped green body having a plurality of through holes;
Cooling means for cooling the green body by supplying a coolant to the through-hole of the green body;
A conveying means for conveying the green body,
The green honeycomb molded body manufacturing apparatus, wherein the green body is cooled by the cooling means while being conveyed by the conveying means. It further comprises heating means for heating and drying the green body,
The manufacturing apparatus according to claim 6, wherein the green body is cooled by the cooling unit while being conveyed by the conveying unit after being heated by the heating unit.   The manufacturing apparatus according to claim 7, wherein the green body is cooled by the cooling unit after being heated by the heating unit in the same container. The manufacturing apparatus according to claim 7 or 8, wherein the heating means is a microwave heating apparatus that irradiates the green body with microwaves.

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