JP5439089B2 - Manufacturing method of honeycomb structure - Google Patents

Description

  The present invention relates to a method for manufacturing a honeycomb structure for obtaining a honeycomb structure in which a closed hollow portion is formed by closing a bottomed hole interposed between through holes.

  As one type of heat storage type heat exchanger, a honeycomb having a plurality of fluid passages formed therethrough and a heat storage body containing portion interposed between the fluid passages and sealed at one end is formed. What has a structure is known (for example, patent document 1). This type of regenerative heat exchanger is used, for example, when preheating air supplied to a gas turbine heat exchanger or a boiler.

  Here, a phase change material that causes a phase transformation from a solid phase to a liquid phase or vice versa according to temperature is accommodated in the heat storage body accommodating portion. This phase change material functions as a heat storage body.

  The phase change material is a solid phase at room temperature. When a high-temperature heat medium (fluid) is circulated through the fluid flow path in this state, heat is transferred from the heat medium to the phase change material. As a result, the phase change material melts and changes to a liquid phase. During this phase change, latent heat is accumulated in the phase change material.

  Next, for example, when a fluid to be heated (for example, air) to be preheated flows through the fluid flow path, heat is transferred from the phase change material to air. Corresponding to this heat transfer, the temperature of the phase change material drops, causing the phase change material to undergo phase transformation from the liquid phase to the solid phase. During this phase transformation, the phase change material releases the accumulated latent heat. Therefore, heat can be transferred to a large amount of fluid to be heated. In addition, since the phase change material maintains a constant temperature during this phase change, the temperature of the air after preheating becomes substantially constant.

JP 11-264683 A

  In the heat storage type heat exchanger described in Patent Document 1, one end of the heat storage body accommodating portion is closed by a plugging material, thereby preventing the phase change material (heat storage body) changed to a liquid phase from flowing out. ing. On the other hand, the other end of the heat storage body accommodation part is opened, and the phase change material is exposed.

  The direction of the heat storage heat exchanger is set so that the closed one end faces downward. For this reason, a fluid flow path and a thermal storage body accommodating part are extended along a perpendicular direction. This is because the phase change material flows out when the opened other end is directed downward.

  In this case, liquid or heated steam cannot be circulated as the fluid to be heated. When such a fluid to be heated enters the heat storage body accommodating portion from the upper end of the opening and comes into contact with the phase change material, there is a concern that the phase change material may be accompanied by the fluid to be heated and flow out or may be altered. Because it is done.

  Moreover, the use of the honeycomb structure is not limited to the heat storage type heat exchanger. Therefore, there are cases where a honeycomb structure in which a closed hollow portion that does not contain a heat storage body is formed is desired. However, a manufacturing method for obtaining such a honeycomb structure has not been proposed yet.

  The present invention has been made to solve the above-described problems, and is a regenerative heat exchanger capable of flowing a liquid, heated steam, or the like as a fluid without restricting the flow direction of the fluid. It is an object of the present invention to provide a method for manufacturing a honeycomb structure capable of obtaining a honeycomb structure that can be suitably used as a substrate.

In order to achieve the above object, the present invention is a method for manufacturing a honeycomb structure in which a plurality of through holes are formed and a closed hollow portion is interposed between the through holes,
A step of forming a honeycomb formed body in which a plurality of through holes are formed and a bottomed hole is interposed between the through holes;
A step of closing the opening of the bottomed hole to form a closed hollow portion;
It is characterized by having.

  Through such a process, a honeycomb structure in which a plurality of through holes are formed and a closed hollow portion is interposed between the through holes can be easily obtained.

  In addition, the heat storage body, that is, a phase change substance that causes a phase transformation from a solid phase to a liquid phase or vice versa according to a temperature change may be accommodated in the closed hollow portion to constitute a heat storage heat exchanger. . In this case, first, the step of accommodating the heat storage body in the bottomed hole may be performed, and then the step of forming the closed hollow portion by closing the opening of the bottomed hole may be performed.

  In this case, the through hole functions as a fluid flow path, and the closed hollow portion serves as the heat storage body accommodation portion. That is, in this heat storage type heat exchanger, the heat storage body is sealed in the heat storage body housing portion, thereby sealing the heat storage body. For this reason, a thermal storage body does not expose.

  In addition, liquid, heated steam, or the like can be circulated as the fluid to be heated. As described above, since the heat storage body is enclosed in the closed hollow portion, there is no concern that the heat storage body is entrained by the liquid or the like and flows out of the honeycomb structure, and the heat storage body is in contact with the liquid or the heated steam. This is because there is no concern of changing the quality.

  Thus, various types of heated fluid can be circulated through the honeycomb structure having the above-described configuration.

  In addition, the following 1st-3rd methods are illustrated as a concrete method of obstruct | occluding the opening of a bottomed hole. In the first method, the opening of the bottomed hole is closed with a previously formed closing material.

  In this case, the side wall of the plugging material can be firmly joined to the inner wall of the opening by firing the honeycomb formed body and the plugging material after the plugging. Further, the plugging material is sintered to form a dense sintered body.

  Here, it is preferable that the honeycomb formed body is fired before the heat storage body is accommodated, that is, the honeycomb formed body is sintered in advance and sufficiently contracted. As a result, even when a material having a thermal shrinkage different from that of the honeycomb molded body is adopted as the material of the plugging material, the plugging material and the honeycomb molded body are heated when the plugging material is fired. The inconvenience that the blocking material is not joined due to the mismatch of the shrinkage rates is avoided. This is because the honeycomb formed body has already sufficiently contracted as described above.

  The second technique is a technique in which the opening of the bottomed hole is closed with a viscous material, and thereafter, the honeycomb formed body and the viscous material are subjected to a firing treatment. In this case, both the honeycomb formed body and the viscous body can be simultaneously formed into a dense sintered body by a single firing process.

  The third technique is a technique in which a coating agent that cures by a chemical reaction is interposed between the opening of the bottomed hole and the blocking material, and then the coating agent is cured by a chemical reaction. In order to interpose the coating agent between the opening and the blocking material, the coating material may be inserted into the opening after the coating agent is applied to either the inner wall of the opening or the blocking material. Of course, the coating agent may be applied to both the inner wall of the opening and the blocking material.

  Specific examples of the chemical reaction include any of hydration reaction, acid-alkali reaction, and sol-gel reaction. Cement or hydraulic alumina is exemplified as one that hardens with the hydration reaction.

  In any case, it is preferable that the bottomed hole is formed so as to expand in a tapered shape from the opening toward the bottom or in the opposite direction.

  For example, when this honeycomb structure is used as a heat storage type heat exchanger as described above, the heat medium is circulated from the expanded side, while the heated medium is circulated from the reduced side. Thus, when the heat storage body undergoes a phase transformation from the solid phase to the liquid phase, melting (expansion) starts from the expansion side and proceeds toward the reduction side, and when the phase transformation from the liquid phase to the solid phase occurs, the reduction side. From this point, solidification (shrinkage) starts and proceeds toward the expansion side. When the heat storage body expands or contracts, stress is generated along with this, but by providing directionality to expansion and solidification as described above, the wall of the closed hollow portion (heat storage body storage section) that stores the heat storage body is formed. Excessive stress can be avoided.

  In order to obtain this effect, it is preferable to set the taper angle of the heat storage body accommodation portion within a range of 0.5 ° to 5 °. If the angle is less than 0.5 °, the above-described effect tends to be poor. On the other hand, when the angle is larger than 5 °, the amount of heat storage 18 is reduced, so that the heat radiation amount is reduced.

  Furthermore, a gel casting method is preferable as a method for producing the honeycomb formed body. This is because according to the gel casting method using slurry, even a molded body having a complicated shape can be molded more easily than press molding.

  Specifically, a mold having a through hole forming part for forming the through hole, a mold having a bottomed hole forming part for forming a bottomed hole, the through hole forming part, and the A cavity is formed by combining with a mold in which a hollow portion into which a bottom hole forming portion is inserted is formed. Of course, the shape of the cavity corresponds to the shape of the honeycomb formed body.

  Therefore, the honeycomb formed body can be easily obtained by filling the cavities with slurry and then solidifying the slurry.

  According to the present invention, since the opening of the bottomed hole is closed after the bottomed hole is formed, a honeycomb structure in which the closed hollow portion is formed can be easily obtained.

  And, for example, after storing the heat storage body in the bottomed hole, the opening of the bottomed hole is closed to form a closed hollow portion, and a heat storage heat exchanger in which the heat storage body is sealed in the closed hollow portion is configured. Then, in this heat storage type heat exchanger, it is possible to avoid the supplied heat medium and fluid to be heated from coming into direct contact with the heat storage body. For this reason, the heat storage body which contacted the fluid may change in quality, and the concern that a heat storage body is accompanied by the fluid and flows out can be wiped off.

  Therefore, it is possible to circulate various types of heated fluid.

1 is an overall schematic perspective view of a heat storage exchanger configured to include a honeycomb structure according to an embodiment of the present invention. It is the II-II sectional view taken on the line of FIG. It is a top view from the upper part of the heat storage type exchanger of FIG. It is a whole schematic perspective view of the heat storage type exchanger which concerns on another embodiment. It is a schematic flow of the 1st manufacturing method for obtaining the heat storage type | mold exchanger shown by FIGS. It is a whole schematic exploded perspective view of the shaping | molding die used in order to obtain the said thermal storage type | mold exchanger. [Fig. 3] Fig. 3 is an overall schematic exploded perspective view showing a state in which a heat storage body formed body is housed in a heat storage body housing portion in the obtained honeycomb formed body. FIG. 3 is an overall schematic exploded perspective view showing a state in which the opening of the heat storage body housing portion is plugged with a plugging material for the honeycomb formed body in which the heat storage body housing body is housed in the heat storage body housing portion. It is a schematic flow of the 2nd manufacturing method for obtaining the heat storage type | mold exchanger shown by FIGS. It is a schematic flow of the 3rd manufacturing method for obtaining the heat storage type | mold exchanger shown by FIGS. It is the whole general | schematic longitudinal cross-sectional view in alignment with the perpendicular direction of the heat storage type exchanger which concerns on another embodiment. It is the whole outline | summary disassembled perspective view of the shaping | molding die used in order to obtain the thermal storage type exchanger which concerns on the said another embodiment. It is a whole schematic exploded perspective view which shows the state which accommodates the molded object of a thermal storage body with respect to the thermal storage body accommodating part of the honeycomb molded body (or honeycomb structure) which comprises the thermal storage type exchanger which concerns on said another embodiment.

  Hereinafter, a preferred embodiment of the method for manufacturing a honeycomb structure according to the present invention in relation to a heat storage type heat exchanger will be described and described in detail with reference to the accompanying drawings.

  1 to 3 are an overall schematic perspective view of the regenerative heat exchanger 10, a cross-sectional view taken along line II-II in FIG. 1, and a plan view from above. In this heat storage type heat exchanger 10, a plurality of fluid flow paths 12 (through holes) are formed so as to penetrate from the lower side to the upper side in FIG. It has a honeycomb structure 16 in which (closed hollow part) is interposed. Further, a heat storage body 18 is enclosed in each of the heat storage body accommodation portions 14.

  As shown in FIGS. 2 and 3, in this case, four fluid flow paths 12 and heat storage body accommodation portions 14 are formed in one row, and the fluid flow paths 12 and the heat storage body accommodation portions 14 are alternately arranged in each row. Be placed. For this reason, the heat storage body accommodation part 14 is interposed between the fluid flow paths 12 and 12.

  The fluid flow path 12 is formed so as to extend from the lower end surface to the upper end surface in FIGS. 1 and 2 of the honeycomb structure 16, and the horizontal cross section thereof is set to be substantially square (see FIGS. 1 and 3). . The horizontal cross-sectional area is substantially the same along the axial direction.

  On the other hand, the heat storage body accommodation part 14 is extended substantially in parallel with the fluid flow path 12 (refer FIG. 1), and the horizontal cross section is set to a substantially square. Here, the horizontal cross-sectional area of the heat storage body accommodating portion 14 gradually increases from the lower end surface toward the upper end surface. That is, the heat storage body accommodation part 14 becomes a shape which expands in a taper shape as it goes to an upper end from a lower end (refer FIG. 2).

  It is preferable that the taper angle θ of the heat storage body accommodation portion 14 is in the range of 0.5 ° to 5 °. If the angle is less than 0.5 °, the effect (to be described later) of relaxing the stress when the heat storage body 18 undergoes a phase transformation from the liquid phase to the solid phase or vice versa tends to be poor. On the other hand, when the angle is larger than 5 °, the amount of heat storage 18 is reduced, so that the heat radiation amount is reduced.

  As can be seen from FIG. 2, the heat storage body accommodation section 14 contains the heat storage body 18 (phase change material) in a bottomed hole whose lower end is closed and the upper end is opened, and further, the upper end is closed by the closing material 20. It is formed by being. The heat accumulator 18 is enclosed in the heat accumulator housing portion 14 by closing the lower end and the upper end.

  As will be described later, the plugging material 20 is inserted into the opening of the heat storage body housing portion 14 after housing the heat storage body 18. In an example of a manufacturing method to be described later, heat treatment is performed after the insertion, whereby the side surface of the blocking material 20 is joined to the inner wall of the opening.

  Suitable materials for the honeycomb structure 16 configured as described above include heat-resistant ceramics such as alumina, cordierite, silicon nitride, boron nitride, silicon carbide, and stabilized zirconia. This type of heat-resistant ceramic can also be selected as the material of the plugging material 20, but it is preferable that the material is the same as that of the honeycomb structure 16 or a material having a smaller thermal expansion coefficient than that of the honeycomb structure 16. In this case, the thermal expansion coefficients of the honeycomb structure 16 and the plugging material 20 are matched, or the thermal expansion coefficient of the plugging material 20 is small, so that the honeycomb structure 16 and the plugging material 20 are prevented from separating. Because you can.

  As will be described later, the heat accumulator 18 is produced as a solid corresponding to the shape of the heat accumulator accommodating portion 14, that is, a shape that expands in a tapered shape from the lower end toward the upper end, and this solid is the heat accumulator accommodating portion. 14 is inserted.

As the material of the heat storage body 18, a material that is a solid phase at normal temperature and becomes a liquid phase when a heat medium is circulated through the fluid flow path 12 and has a relatively large latent heat is selected. Suitable examples thereof include nitrates such as LiNO ₃ , NaNO ₃ , NaNO ₂ and KNO ₃ , chloride salts such as LiCl, NaCl, MgCl ₂ , KCl and ZnCl ₂ , and alkali metals such as LiCO ₃ and K ₂ CO _3. Mention may be made of carbonates.

In addition, a eutectic salt may be used. Specific examples of suitable eutectic salts include NaCl / MgCl ₂ , NaOH / NaCl, NaCl / MgCl ₂ / KCl, and the like.

  When the heat storage body 18 undergoes a phase transformation from the solid phase to the liquid phase, the volume increases. For this reason, when the heat storage body 18 is a solid phase, a clearance 22 is provided between the upper end surface of the heat storage body 18 in FIG. When the solid-phase heat storage body 18 is fully filled in the heat storage body housing portion 14 without providing the clearance 22, when the heat storage body 18 becomes a liquid phase and the volume increases, the heat storage body housing portion 14 and the blockage are increased by the increase. This is because an excessive pressing force acts on the wall surface of the material 20, and this is avoided.

  The regenerative heat exchanger 10 basically configured as described above is used as follows.

  When no fluid flows through the fluid flow path 12 of the heat storage type heat exchanger 10, the heat storage type heat exchanger 10 is at room temperature, and the heat storage body 18 housed in the heat storage body housing portion 14 is a solid phase.

  Next, in order to store heat in the heat storage type heat exchanger 10, a heat medium is circulated through the fluid flow path 12. At this time, the heat medium is circulated from the upper side to the lower side in FIG. 1 and FIG. 2 (along the arrow X2 direction). That is, the heat medium has a smaller end (on the bottom side of the bottomed hole) from the end on the side where the cross-sectional area in the horizontal direction of the heat storage body accommodating portion 14 is larger (the end on the side closed with the closing material 20). It circulates toward the end.

  When the heat medium is circulated through the fluid flow path 12, the heat from the heat medium is transmitted to the heat storage body 18 enclosed in the heat storage body accommodation portion 14 adjacent to the fluid flow path 12. Along with this, the temperature of the heat storage body 18 rises.

  When the temperature rise continues and reaches the melting point of the heat storage body 18, the heat storage body 18 melts. That is, it transforms from a solid to a liquid phase. During this phase transformation, the heat storage body 18 maintains a constant temperature and accumulates thermal energy as latent heat.

  The volume of the heat storage body 18 transformed into the liquid phase increases. Here, as described above, since the clearance 22 is provided in the heat accumulator accommodating portion 14 (see FIG. 2), the increased volume is stored by the clearance 22. For this reason, it is avoided that the heat storage body 18 which became the liquid phase presses the wall surface of the heat storage body accommodating part 14 and the obstruction | occlusion material 20. FIG. In other words, it is possible to effectively avoid an excessive pressing force acting on these wall surfaces.

  Moreover, since a heat medium distribute | circulates along the arrow X2 direction, the thermal storage body 18 fuse | melts previously from the upper side. That is, the phase transformation to the liquid phase occurs sequentially from the upper side to the lower side of the heat storage body 18.

  As described above, the horizontal cross-sectional area of the heat storage body accommodation portion 14 is larger on the upper side than on the lower side. That is, the heat storage body accommodating portion 14 is set to have a large area on the upper side where the melting occurs first in the heat storage body 18. For this reason, compared with the case where the cross-sectional area of the heat storage body accommodation part 14 is made constant along the extending direction, the stress which acts on the wall surface of the heat storage body accommodation part 14 can be reduced.

  When it is confirmed that the heat storage body 18 has reached a predetermined temperature after the heat storage body 18 has melted, the fluid flowing through the fluid flow path 12 is switched from the heat medium to the heated fluid to be preheated. It is done. Of course, the temperature of the fluid to be heated is lower than the temperature of the heat storage body 18.

  The fluid to be heated is circulated from the lower side to the upper side (along the arrow X1 direction) in FIGS. As described above, since the heat storage body 18 is sealed by closing the heat storage body accommodating portion 14, the heat storage heat exchanger 10 is installed sideways and the heat medium is moved from left to right or vice versa. It is also possible to distribute in the direction.

  This heated fluid may be a gas or a liquid. Moreover, heated steam may be sufficient. As described above, since the heat accumulator 18 is enclosed in the heat accumulator accommodating portion 14, there is no concern that the heat accumulator 18 is entrained by the liquid or the like and flows out of the honeycomb structure 16, and the heat accumulator 18 is liquid or This is because there is no concern of deterioration due to contact with heated steam.

  When the fluid to be heated is circulated through the fluid flow path 12, the heat accumulated in the heat storage body 18 enclosed in the heat storage body accommodation portion 14 adjacent to the fluid flow path 12 is taken away by the fluid to be heated. In other words, heat release from the heat storage body 18 to the fluid to be heated occurs. With this heat radiation, the temperature of the fluid to be heated increases and the temperature of the heat storage body 18 decreases.

  When the fluid to be heated is heated in this manner, the heat storage body 18 that has dissipated heat undergoes a phase transformation from the liquid phase to the solid phase. During this phase transformation, the thermal energy accumulated in the heat storage body 18 is released as latent heat. For this reason, the temperature of the heat storage body 18 is maintained constant. Accordingly, the temperature of the heated fluid discharged from the fluid flow path 12 is also substantially constant.

  Moreover, since the to-be-heated fluid distribute | circulates along the arrow X1 direction, the thermal storage body 18 solidifies previously from the downward side. That is, the phase transformation to the solid phase occurs sequentially from the bottom to the top of the heat storage body 18.

  As described above, the horizontal cross-sectional area of the heat storage body accommodation portion 14 is larger on the upper side than on the lower side. In other words, the heat storage body accommodating portion 14 is set to have a small area on the lower side where solidification first occurs in the heat storage body 18. For this reason, compared with the case where the cross-sectional area of the heat storage body accommodation part 14 is made constant along the extending direction, the stress which acts on the wall surface of the heat storage body accommodation part 14 can be reduced.

  As described above, according to the present embodiment, the flow direction of the heat medium and the fluid to be heated is not restricted, and when the heat storage body 18 undergoes phase transformation, it acts on the wall surface of the heat storage body accommodation portion 14. The regenerative heat exchanger 10 that can sufficiently reduce the stress to be generated can be configured.

  In addition, as shown in FIG. 4, you may make it provide the protrusion 24 for turbulent flow formation in the inner wall of the fluid flow path 12. As shown in FIG. Here, in FIG. 4, a rectangular column-shaped turbulent flow projection extending along the axial direction of the fluid flow path 12 on each inner wall of the fluid flow path 12 having a substantially square cross section in the horizontal direction. Although an embodiment in which 24 (a total of four) is formed is shown, only one protruding from any one wall surface may be used. Of course, the number of the turbulent flow forming projections 24 may be two or three. Further, two or more turbulent flow forming projections 24 may be provided for each wall surface.

  When such a turbulent flow forming projection 24 is provided, the surface area of the fluid flow path 12 is increased, and the heat medium and the heated fluid flowing through the fluid flow path 12 become turbulent. Therefore, since the heat exchange efficiency with the heat storage body 18 improves, it is more suitable.

  The turbulent flow formation projection 24 is not particularly limited to a quadrangular prism shape, and may be a semi-cylindrical shape or a triangular prism shape. Alternatively, a plurality of spherical protrusions (so-called spinies) may be used.

  The regenerative heat exchanger 10 shown in FIGS. 1 to 3 can be manufactured by, for example, the following first to third manufacturing methods.

  First, the first manufacturing method will be described with reference to FIG. The first manufacturing method includes a first step S1 in which a forming die 30 shown in FIG. 6 is filled and solidified with slurry to form a honeycomb forming body 32 (see FIG. 7), and the honeycomb forming body taken out from the forming die 30. A second step S2 for obtaining a honeycomb structure 16 by performing a firing process on the second step 32; a third step S3 for housing a solid-phase heat storage body 18 in the heat storage body housing portion 14 of the honeycomb structure 16; It includes a fourth step S4 for sealing (closing) the body housing portion 14 with the plugging material 20, and a fifth step S5 for performing a firing process on the plugging material 20 and the honeycomb structure 16.

  First, a slurry for obtaining the honeycomb structure 16 is prepared. That is, heat-resistant ceramic powders such as alumina, cordierite, silicon nitride, boron nitride, silicon carbide, and stabilized zirconia, which are raw materials of the honeycomb structure 16, and thermosetting resin powder are added to an organic solvent. Stir and mix.

  In the first step S1, this slurry is filled in the mold 30 shown in FIG. That is, in this embodiment, a gel cast method is adopted.

  Here, the configuration of the mold 30 will be described slightly. The mold 30 includes a lower mold 38 in which a plurality of columnar protrusions 34 for forming the fluid flow path 12 protrude from the lower base 36, a hollow middle mold 40 having a frame shape, and the heat storage body accommodating portion 14. A plurality of tapered protrusions 42 to be formed have an upper mold 46 provided on the upper base 44. Of course, both the columnar protrusion 34 and the tapered protrusion 42 extend toward the middle mold 40.

  The columnar protrusions 34 of the lower mold 38 are set so that the horizontal cross section has a substantially square shape and the cross sectional area thereof is substantially the same along the axial direction. The height direction dimension H1 of the columnar protrusion 34 is substantially the same as the height direction dimension H2 of the middle mold 40. Therefore, when both the columnar protrusion 34 and the tapered protrusion 42 are inserted into the middle mold 40, The upper end surface comes into contact with the lower end surface of the upper base 44 constituting the upper mold 46 (the surface on which the tapered protrusions 42 are provided).

  On the other hand, the tapered protrusion 42 provided on the upper die 46 has a substantially square cross section in the horizontal direction, but its cross-sectional area gradually decreases as it approaches the middle die 40. In other words, the tapered protrusion 42 expands in a tapered shape as the distance from the middle mold 40 increases.

  The height direction dimension H3 of the tapered protrusion 42 is shorter than the height direction dimension H2 of the middle mold 40. For this reason, the lower end surface of the tapered protrusion 42 inserted into the middle mold 40 is separated without contacting the upper end surface of the lower base 36 constituting the lower mold 38 (the surface on which the columnar protrusion 34 is provided).

  By inserting both the columnar protrusion 34 and the tapered protrusion 42 into the middle mold 40, the mold 30 is configured, and a cavity (not shown) is formed inside the mold 30. The slurry is introduced into the cavity through a runner (not shown).

  Since the mold 30 is preheated, the thermosetting resin contained in the slurry starts to be cured by receiving this heat. By this curing, the slurry becomes a honeycomb formed body 32 shown in FIG.

  The slurry is not filled in the locations where the columnar protrusions 34 and the tapered protrusions 42 are present. Therefore, in the honeycomb formed body 32, a through hole (fluid flow path 12) is formed in a portion corresponding to the portion where the columnar protrusion 34 is present, while on the portion corresponding to the portion where the tapered protrusion 42 is present, A bottomed hole (heat storage body accommodation portion 14) that is expanded in a tapered shape is formed from the lower die 38 toward the upper die 46. This is because, as described above, the upper end surface of the columnar protrusion 34 contacts the lower end surface of the upper base 44, while the lower end surface of the tapered protrusion 42 is separated from the upper end surface of the lower base 36.

  As understood from the above, the shape of the obtained honeycomb formed body 32 corresponds to the shape of the honeycomb structure 16 (see FIG. 1). The honeycomb formed body 32 is obtained by subjecting the honeycomb formed body 32 to a firing process in the second step S2.

  Next, in 3rd process S3, as shown in FIG. 7, the thermal storage body 18 is accommodated in the thermal storage body accommodating part 14. As shown in FIG. In addition, the heat storage body 18 is shaped in advance so that the shape thereof corresponds to the shape of the heat storage body housing portion 14 and the axial dimension thereof is shorter than the axial direction dimension of the heat storage body housing portion 14. Therefore, as shown in FIG. 8, the upper end surface of the heat storage body 18 is positioned below the upper end surface of the honeycomb structure 16.

  In order to obtain the heat storage body 18 molded in this way, the raw material of the heat storage body 18 is melted, and this melt is shaped to correspond to the heat storage body accommodation section 14 and the dimension in the axial direction is the heat storage body accommodation section 14. What is necessary is just to fill and solidify a cavity short compared with. Alternatively, after obtaining a rod-like or columnar shaped body from the melt, the shaped body may be ground.

  Next, in 4th process S4, as shown in FIG. 8, opening of the thermal storage body accommodating part 14 is obstruct | occluded with the obstruction | occlusion material 20 produced beforehand as a molded object. As described above, the material of the plugging material 20 is preferably the same as that of the honeycomb structure 16.

  Specifically, the closing material 20 is inserted into the opening of the heat storage body accommodation portion 14. Of course, the size of the closing material 20 is set so as to substantially correspond to the size of the opening of the heat storage body accommodating portion 14, and therefore, there is almost no clearance between the side wall of the closing material 20 and the inner wall of the opening. . Therefore, the opening of the heat storage body accommodation part 14 is firmly sealed with the closing material 20, and eventually the heat storage body 18 is enclosed in the heat storage body accommodation part 14. Note that the upper end surface of the plugging material 20 is substantially flush with the upper end surface of the honeycomb structure 16.

  Next, in the fifth step S5, the plugging material 20 and the honeycomb structure 16 are fired. By this firing treatment, co-sintering of the side wall of the plugging material 20 and the inner wall of the opening occurs, and as a result, the plugging material 20 is firmly bonded to the honeycomb structure 16.

  As described above, the heat storage type heat exchanger 10 (see FIGS. 1 to 3) in which the heat storage body 18 is sealed in the sealed heat storage body housing portion 14 is obtained.

  As shown in FIG. 4, when the turbulent flow forming protrusion 24 is provided in the fluid flow path 12, the shape of the turbulent flow forming protrusion 24 is different from the columnar protrusion 34 (see FIG. 6) of the lower mold 38. What is necessary is just to form the recessed part of the shape corresponding to. The same applies to the following second manufacturing method and third manufacturing method.

  Next, the second manufacturing method will be described with reference to FIG.

  Whereas the first manufacturing method uses a pre-molded plugging material 20 to close the heat storage body accommodation portion 14, the second manufacturing method closes the heat storage body accommodation portion 14 with a viscous material such as paste or clay. It is. That is, in the second manufacturing method, the first step S10 (step of solidifying the slurry to form the honeycomb formed body 32), which is performed in accordance with each of the first step S1 and the third step S3, the second step After the step S20 (the step of housing the solid-phase heat storage body 18 in the heat storage body housing portion 14 of the honeycomb formed body 32) is performed, in the third step S30, the paste and the viscosity with respect to the opening of the heat storage body housing portion 14 Etc. are applied.

  The viscous material can be preferably prepared by adding a relatively large amount of ceramic powder of the same material as the honeycomb molded body 32 (honeycomb structure 16) and a thermosetting resin powder to a solvent. The viscous body is applied so that the opening of the heat storage body accommodation portion 14 is closed. At this time, it is not particularly necessary that the upper end surface of the viscous body and the upper end surface of the honeycomb formed body 32 be flush with each other.

  Here, the viscous body has a predetermined viscosity. Therefore, it is avoided that the viscous material applied to the opening of the heat storage body accommodating portion 14 drops toward the heat storage body 18. In other words, by using the viscous body, it is possible to seal the heat storage body accommodation portion 14 while avoiding the heat storage body accommodation portion 14 being filled with the viscous body.

  Next, in the fourth step S <b> 40, heat treatment is performed on the viscous body that closes the heat storage body accommodation portion 14 and the honeycomb formed body 32. By this heat treatment, the honeycomb formed body 32 is sintered to become the honeycomb structure 16, and at the same time, the viscous body is sintered to become the plugging material 20. As a result, the heat storage type heat exchanger 10 (see FIGS. 1 to 3) in which the heat storage body 18 is sealed in the sealed heat storage body housing portion 14 is obtained.

  As can be understood by comparing FIG. 5 and FIG. 9, in the second manufacturing method, it is only necessary to perform the baking process once. That is, the number of firing processes can be reduced, and therefore the regenerative heat exchanger 10 can be efficiently produced. That is, the production efficiency of the regenerative heat exchanger 10 is improved.

  Next, the third manufacturing method will be described with reference to FIG.

  In the third production method, instead of the viscous material used in the second production method, a self-curing coating agent that spontaneously cures with some reaction is used. That is, in the third manufacturing method, after the first step S100 to the third step S300 performed in accordance with each of the first step S1 to the third step S3 of the first manufacturing method, In 4 processes S400, the said coating agent is apply | coated to the opening of the thermal storage body accommodating part 14 of the honeycomb structure 16, and the obstruction | occlusion material 20 produced beforehand as a baking body, and obstruction | occlusion is performed.

  Preferable examples of the coating agent include those that spontaneously cure over time due to a hydration reaction, such as cement and hydraulic alumina. Or you may form a strong bond with an acid-alkali reaction. In this case, an acid treatment or a base treatment may be performed on the opening of the heat storage body accommodation portion 14 and the closing material 20 that is previously prepared as a fired body.

  Furthermore, a synthetic reaction such as a sol-gel method may be performed.

  The coating agent begins to harden before being applied to the opening of the heat storage body accommodation unit 14. For this reason, it is applied to the opening in a state showing viscosity. Therefore, also in this case, the heat storage body accommodation portion 14 can be sealed while avoiding the coating agent filling the heat storage body accommodation portion 14.

  When the coating agent is cement, hydraulic alumina, or the like, if it is allowed to stand after coating, the hydration reaction proceeds to cure spontaneously. Moreover, what is necessary is just to perform an acid treatment or a base treatment, when an acid-alkali reaction is advanced and a coating agent is hardened.

  In this way, the blocking agent 20 is bonded by curing the coating agent. As a result, the heat storage type heat exchanger 10 (see FIGS. 1 to 3) in which the heat storage body 18 is sealed in the sealed heat storage body housing portion 14 is obtained.

  As can be understood by comparing FIG. 5 and FIG. 10, the third manufacturing method also requires only one firing process. For this reason, the heat storage type heat exchanger 10 can be produced efficiently. That is, there is an advantage that the production efficiency of the regenerative heat exchanger 10 is improved.

  In addition, this invention is not limited to embodiment mentioned above, Of course, a various structure can be taken in the range which does not deviate from the summary of this invention.

  For example, as shown in FIG. 11, the horizontal cross-sectional area may be made substantially the same without expanding the heat storage body accommodation portion 50 in a tapered shape. In this case, as shown in FIG. 12, a rectangular columnar protrusion 52 extending toward the middle mold 40 may be provided on the lower end surface of the upper base 44. Of course, the height direction dimension H4 of the square columnar protrusion 52 is set shorter than the height direction dimension H2 of the middle die 40. In addition, as shown in FIG. 13, the heat storage body 18 may also have a quadrangular prism shape.

  Moreover, it is good also considering the horizontal direction cross section of both the fluid flow path 12 and the thermal storage body accommodating part 14 as a circle. In this case, columnar protrusions may be provided on the lower mold 38 and the upper mold 46. When the diameter of the heat accumulating member accommodating portion 14 is reduced in a tapered shape, the upper mold 46 may be provided with a truncated cone-shaped protrusion that decreases in diameter toward the middle mold 40.

  Furthermore, you may make it form a thermal storage body accommodating part as what was expanded in the taper shape as it goes to opening from the bottom part of a bottomed hole. In this case, when the heat medium is circulated through the fluid flow path 12, the heat medium is directed from the opening of the bottomed hole toward the bottom side (from the side having the larger cross-sectional area in the horizontal direction of the heat storage body housing portion to the smaller side). When the fluid to be heated is circulated, the fluid to be heated may be directed from the bottom side of the bottomed hole to the opening side (the side where the horizontal cross-sectional area of the heat storage body accommodation portion is small to the large side). As a result, similarly to the above, it is possible to avoid an excessive stress from acting on the wall surface of the heat storage body accommodation portion 14 when a phase transformation occurs from the solid phase of the heat storage body 18 to the liquid phase or vice versa.

  In above-mentioned embodiment, although the manufacturing method of the honeycomb structure 16 is included in the manufacturing method of the heat storage type heat exchanger 10, the heat storage body 18 is provided with respect to the heat storage body accommodating part 14 (bottomed hole). If the housing step is omitted, a closed hollow portion in which the bottomed hole is closed by the closing material 20 is formed in the honeycomb structure 16. The present invention also includes this manufacturing method for obtaining the honeycomb structure 16 that does not include the heat storage body 18. In the honeycomb structure 16 in this case, the fluid flow path 12 of the heat storage type heat exchanger 10 corresponds to a through hole.

  That is, according to the present invention, it is also possible to obtain a honeycomb structure 16 in which a through hole and a closed hollow portion that is interposed between the through holes and does not contain the heat storage body 18 are formed.

DESCRIPTION OF SYMBOLS 10 ... Thermal storage type heat exchanger 12 ... Fluid flow path 14, 50 ... Thermal storage body accommodating part 16 ... Honeycomb structure 18 ... Thermal storage body 20 ... Occlusion material 22 ... Clearance 24 ... Turbulence formation protrusion 30 ... Mold 32 ... Honeycomb Molded body 34 ... columnar protrusion 38 ... lower mold 40 ... medium mold 42 ... tapered protrusion 46 ... upper mold 52 ... square columnar protrusion

Claims (10)

A method for manufacturing a honeycomb structure in which a plurality of through holes are formed and a closed hollow portion is interposed between the through holes,
A step of forming a honeycomb formed body in which a plurality of through holes are formed and a bottomed hole is interposed between the through holes;
A step of closing the opening of the bottomed hole to form a closed hollow portion;
A method for manufacturing a honeycomb structure, comprising:   The manufacturing method according to claim 1, further comprising a step of accommodating a heat storage body made of a phase change material that causes a phase transformation from a solid phase to a liquid phase or vice versa according to a temperature change in the bottomed hole, A method for manufacturing a honeycomb structure, wherein a step of forming the closed hollow portion is performed after this step.   3. The manufacturing method according to claim 1, wherein the opening of the bottomed hole is closed with a previously formed plugging material, and thereafter, the honeycomb molded body and the plugging material are fired. A method for manufacturing a honeycomb structure. The method for manufacturing a honeycomb structure according to claim 2 , wherein the honeycomb formed body is fired before the heat storage body is accommodated.   3. The manufacturing method according to claim 1, wherein the opening of the bottomed hole is closed with a viscous body, and then the honeycomb formed body and the viscous body are subjected to a firing treatment to cure the viscous body. A method for manufacturing a honeycomb structure, characterized by using a plugging material. The manufacturing method according to claim 1 or 2, wherein the coating material which is cured by a chemical reaction is interposed between the opening and closing塞材of the blind hole, then, characterized in that curing the coating material by chemical reaction A method for manufacturing a honeycomb structure.   7. The method for manufacturing a honeycomb structure according to claim 6, wherein any one of a hydration reaction, an acid-alkali reaction, and a sol-gel reaction is allowed to proceed as the chemical reaction.   The manufacturing method according to any one of claims 1 to 7, wherein the bottomed hole is formed so as to expand in a tapered shape from the opening toward the bottom or in the opposite direction. A method for manufacturing a honeycomb structure.   The method for manufacturing a honeycomb structure according to claim 8, wherein the taper angle of the bottomed hole is set to 0.5 ° to 5 °.   The manufacturing method according to any one of claims 1 to 9, further comprising a mold having a through hole forming portion for forming the through hole, and a bottomed hole forming portion for forming a bottomed hole. Forming a cavity with a mold having a hollow part into which the through hole forming part and the bottomed hole forming part are inserted, and filling the cavity with slurry and solidifying the honeycomb formed body A method for manufacturing a honeycomb structure, comprising: obtaining a honeycomb structure.

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