JP2010279936A - Gas cleaning filter and method of manufacturing gas cleaning filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a gas cleaning filter that is used at high temperature, and hardly causes cracks even when the temperature distribution in a filter base body is uneven. <P>SOLUTION: The gas cleaning filter disposed in a gas flow path and collecting substances in gas includes: a filter body 1a formed of a porous ceramic sintered compact, with a non-jointing type integrated structure equipped with a plurality of cells partitioned by partition walls extended in a row in a single axial direction Z; and slit parts 11 opened at ends Ed serving as downstream sides of the gas flow of the filter body, and extending toward ends Eu without reaching the ends Eu serving as upstream sides. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a gas purification filter and a method for manufacturing the same, and more particularly to a gas purification filter that may be used at high temperatures and a method for manufacturing the same.

  In many filters used at high temperatures, the occurrence of cracks due to heating becomes a problem. For example, a diesel particulate filter (hereinafter sometimes referred to as “DPF”) that collects particulate matter contained in gas discharged from a diesel engine is used when the collected particulate matter has accumulated to some extent. Then, a regeneration process for burning the particulate matter by self-heating or external heating is performed. At this time, if the temperature distribution in the filter base becomes non-uniform, there is a risk that cracks will occur in the filter base due to thermal stress. And when a crack generate | occur | produces in a filter base | substrate, the particulate matter discharged | emitted with waste gas without being collected by DPF will increase.

  Therefore, a joining type DPF in which a filter base is formed by joining a plurality of segments and thermal stress is mitigated by a sealing material layer between the segments has been proposed (see, for example, Patent Document 1). ing. Here, in the technique of Patent Document 1, a plurality of segments are bonded with a sealing material composed of inorganic fibers, an inorganic binder, an organic binder, and inorganic particles, and the thermal stress generated in each segment is absorbed and relaxed by the sealing material layer. At the same time, the plurality of segments are to be firmly joined by the sealing material layer.

  However, as described above, in the conventional bonded DPF in which a plurality of segments are bonded with a sealing material as described above, it cannot be said that the thermal stress is sufficiently relaxed. As an example, FIG. 8 shows a temperature distribution when a regeneration process is performed after depositing particulate matter on a DPF 100 in which a plurality of segments formed of silicon carbide ceramics are bonded with a silicon carbide sealing material. Show. Here, the DPF 100 used in the measurement was formed into a cylindrical shape having a diameter of 5.66 inches and a length of 10 inches after joining 4 × 4 segments having a cell density of 150 cpsi and a partition wall thickness of 0.4 mm with a sealing material. In the regeneration process, the particulate matter 8g / L is deposited, and after raising the exhaust gas temperature to about 680 ° C, the engine is idling at once and the oxygen supply is increased. This was done by burning particulate matter in a dry environment. FIG. 8 shows the temperature distribution at the time when 30 seconds have elapsed after the start of the regeneration process, and the arrows in the figure show the flow direction of the exhaust gas.

  From FIG. 8, it can be seen that in the DPF 100, the temperature distribution is extremely uneven during the regeneration process. That is, the temperature is extremely high at 900 ° C. or more on the downstream side of the gas flow, and a temperature difference of about 250 ° C. is generated on the upstream end. In addition, the temperature distribution is not uniform in the radial direction, and a temperature difference of about 200 ° C. is generated between the central portion and the peripheral portion of the filter base on the downstream side. As described above, in the junction type DPF in which a plurality of segments are joined, the temperature varies greatly depending on the position of the segment, and the thermal expansion coefficient varies accordingly. In general, the higher the temperature, the greater the difference between the coefficient of thermal expansion of the material constituting the segment and the coefficient of thermal expansion of the sealing material. As a result, in the conventional bonded DPF, a large thermal stress that cannot be relaxed by the sealing material layer is generated, and cracks are often generated.

  Therefore, in view of the above circumstances, the present invention is a gas purification filter that may be used at high temperatures, and a gas purification filter that is unlikely to crack even if the temperature distribution in the filter base is non-uniform, and An object of the present invention is to provide a method for producing the gas purification filter.

In order to solve the above-described problems, a gas purification filter according to the present invention includes:
"A gas purification filter that is disposed in a gas flow path and collects substances in the gas,
A non-joint, monolithic filter body comprising a plurality of cells that are formed of porous ceramics sintered bodies and are partitioned by partition walls extending in a single axial direction;
A slit portion that opens at one end of the filter body and extends in the axial direction toward the other end without reaching the other end of the filter body.

  As the “porous ceramic sintered body”, porous sintered bodies such as silicon carbide, silicon nitride, cordierite, alumina and mullite ceramics can be used.

  The “non-joint and integral structure filter body” is not a joined type but a filter body in which the entire structure formed by arranging a plurality of cells is integrated. Here, the “joint-type” filter body refers to a filter body in which a plurality of segments are joined by a sealing material layer, like the filter body in the conventional DPF.

  In the present invention, since the slit portion is formed along the axial direction on one end side of the filter body, the filter body is divided at that portion, and the space on both sides of the slit portion has a space corresponding to the slit portion. Are separated through. In the following, for convenience of explanation, a part of the filter body in which the slit part is formed is referred to as a “separation type filter part”, and each of a collection of cells separated via the slit part is referred to as a “cell assembly”. I will do it. And although the slit part is extended toward the other end from the one end side of the filter main body, since it has not reached the other end, the filter main body is united without being divided on the other end side. In the following, for convenience of explanation, the filter main body of the integral part without the slit part is referred to as “integrated filter part”.

  According to the present invention having the above-described configuration, in the separation type filter unit, each cell assembly separated through the slit unit can be expanded and contracted without being restricted in movement by the adjacent cell assembly. . In other words, even if the temperature distribution becomes non-uniform and the coefficient of thermal expansion differs between cell assemblies, the individual cell assemblies have a high degree of freedom of thermal expansion at their respective coefficients of thermal expansion. Thereby, it is suppressed that a crack generate | occur | produces in the filter main body resulting from the difference in a thermal expansion coefficient.

  Further, in the present invention, thermal expansion is freely performed for each cell assembly, thereby suppressing the generation of thermal stress. Therefore, unlike a conventional bonded filter, a sealing material layer is provided to reduce thermal stress. There is no need to try. Here, the general sealing material layer is intended to relieve thermal stress due to its elasticity, so it is not fired and has low mechanical strength. However, the filter body of the present invention is a non-bonding type. Since it is a monolithic structure, it does not have a sealing material layer with low strength. And in this invention, the several cell assembly divided | segmented by the slit part in the separation type filter part is united via the integral filter part without a slit part. Therefore, in the present invention, the shape of the entire filter main body is stably maintained although it has a configuration having a portion divided by the slit portion.

The gas purification filter according to the present invention includes:
“The slit portion extends in the axial direction in parallel with the partition wall and extends in a direction perpendicular to the axial direction in parallel with the partition wall”.

  When the slit portion intersects the partition wall, there are many partition walls that cannot perform the filtering action along the slit portion. On the other hand, in the present invention, the slit portion extends in parallel with the partition wall in both the axial direction and the direction perpendicular to the axial direction, and does not intersect the partition wall. Therefore, the partition wall existing along the slit portion is also filtered. Has an effect. Thereby, according to this invention of the said structure, even if it is the structure by which the slit part is provided, the filtering effect | action can fully be exhibited.

The gas purification filter according to the present invention includes:
“The slit portion may be open at an end portion that should be downstream of gas flow in the filter body”.

  When the gas purification filter is used as a DPF, during the regeneration process, as described above, the filter body becomes extremely hot at the downstream side of the gas flow compared to the upstream side, and at the downstream side, compared to the upstream side. The temperature distribution tends to be extremely uneven.

  In the present invention configured as described above, the integral filter portion that cannot be freely expanded and contracted for each part in the filter body is provided on the upstream side where the temperature is not so high during the regeneration process and the temperature difference is not large. Therefore, cracks due to thermal stress are unlikely to occur. On the other hand, the downstream side where the temperature may become extremely high during the regeneration process and the temperature difference is likely to be large is a separation type filter part provided with a slit part, so that each cell assembly has its own coefficient of thermal expansion. Depending on the situation, it can expand freely. Thereby, in this invention, the effect | action that generation | occurrence | production of a crack is reduced by providing a slit part can be acquired more effectively.

The gas purification filter according to the present invention includes:
“The non-adhesive filler layer is formed in the slit portion by a filler that is not bonded to the filter body”.

  Examples of the “non-adhesive filling layer” include a layer formed by inserting ceramic fibers or a sheet-like ceramic material into the space in the slit portion without being bonded.

  When the ratio of the separation filter portion in the filter body is large, in other words, when the ratio of the axial length of the slit portion to the axial length of the filter body is large, the separation is required when the gas purification filter is used. There is a possibility that each cell assembly that is being operated tends to vibrate. On the other hand, in the present invention, the vibration of each cell assembly can be reduced by filling the slit portion with the filler.

  In addition, since the filler filled in the slit portion is not bonded to the filter body, it can slide relative to the cell assembly. As a result, each cell assembly is not limited in its free expansion and contraction by the filler, and the effect of the present invention that each cell assembly can be freely thermally expanded at a thermal expansion coefficient corresponding to each temperature is It is unobstructed by the material.

Next, a manufacturing method of the gas purification filter according to the present invention includes:
“A method for producing a gas purification filter that is disposed in a gas flow path and collects a substance in a gas,
An unfired ceramic material that becomes a porous body when fired, and extrudes a non-joint, integral structure filter body with multiple cells that are partitioned by partition walls extending in a single axial direction. Molding process to mold;
Before or after firing the molded body, it cuts without reaching the other end from one end to the other end in the axial direction, and cuts off the partition wall, thereby opening at the one end and moving toward the other end. A cutting step for forming an extending slit portion;
After the cutting step or prior to the cutting step, a firing step of firing the molded body to obtain a sintered body ”.

  In addition, the method for producing a gas purification filter according to the present invention may be configured such that, in the above configuration, “in the cutting step, the partition wall is perpendicular to the axial direction and the axial direction so that the slit portion does not intersect the partition wall. To be cut in parallel with ". Further, “in the cutting step, cutting is performed from an end portion to be the downstream side of the gas flow toward an end portion to be the upstream side of the gas flow”.

  In addition, the manufacturing method of the gas purification filter according to the present invention includes, in addition to the above-described configuration, “a non-adhesive filling step of filling a filler without adhering the slit body to the filter body after the firing step. Can be included.

  According to the method for manufacturing a gas purification filter having the above-described configuration, the gas purification filter having the above-described configuration can be manufactured, and the above-described excellent operational effects can be obtained.

  As described above, as an effect of the present invention, a gas purification filter that may be used at high temperatures, and a gas purification filter that is less likely to crack even if the temperature distribution in the filter base is non-uniform, and A method for producing the gas purification filter can be provided.

It is the (a) top view seen from the upstream side of the filter main body in one embodiment of the present invention, (b) side view, and (c) AA line end view. It is a BB line end view of the filter main body of FIG. It is CC line end elevation of the filter main body of FIG. It is an AA line end view in case the filter main body of Drawing 1 is further provided with a nonadhesive filling layer. (A) Process drawing which shows the manufacturing method of the filter main body of FIG. 1, (b) It is process drawing which shows the manufacturing method of the filter main body of FIG. 4, (c) The manufacturing method of other embodiment of the filter main body of FIG. FIG. 5D is a process diagram showing a manufacturing method of another embodiment of the filter main body of FIG. 4. FIG. 5A is a process diagram illustrating a method for manufacturing the filter main body of FIG. 1 when performing a cutting process after the sintering process, and FIG. 5B is a process diagram illustrating a method for manufacturing the filter main body of FIG. 4. It is the end view which cut | disconnected the filter main body of other embodiment by the surface perpendicular | vertical to an axial direction in the separation type filter part. It is a figure explaining the temperature distribution at the time of a regeneration process about the conventional junction type diesel particulate filter.

  Hereinafter, a gas purification filter and a method for manufacturing the same according to an embodiment of the present invention will be described with reference to FIGS. Here, the case where the gas purification filter of this invention is applied to the diesel particulate filter which is arrange | positioned in the flow path of the gas discharged | emitted from a diesel engine and collects the particulate matter in gas is illustrated.

  As shown in FIGS. 1 to 3, the gas purification filter according to the present embodiment includes a plurality of cells defined by partition walls 4 formed of a porous ceramic sintered body and extending in a single axial direction Z. A non-joint and integral filter body 1a having a slit 5 that opens in one end of the filter body 1a and extends in the axial direction Z toward the other end without reaching the other end of the filter body 1a; It has. Further, in the filter main body 1 a of the present embodiment, the slit portion 11 extends in the axial direction Z in parallel with the partition wall 4, and extends in a direction perpendicular to the axial direction Z in parallel with the partition wall 4.

  More specifically, the slit portion 11 of the present embodiment is provided so as to divide the filter body 1a into nine cell assemblies 10 so as to penetrate the filter body 1a in the direction perpendicular to the axial direction Z. It is open. Moreover, the slit part 11 has the width | variety of about two cells.

  Moreover, the slit part 11 is opened by the edge part Ed which should become the downstream of a gas distribution | circulation in the filter main body 1a. As a result, in the filter main body 1a, the separation type filter portion Sf is formed on the downstream end portion Ed side, and the integral filter portion Cf is formed on the upstream end portion Eu side. In the present embodiment, the outer shape of the filter body 1a is cylindrical.

  Here, in the filter main body 1a, as shown in the X range enlarged in FIG. 2, the cells 5 are opened in one direction and the cells opened in the other direction are alternately arranged. One end is sealed by the sealing portion 6. When the gas purification filter is disposed in the gas flow passage so that the axial direction Z coincides with the flow direction of the exhaust gas by alternately sealing the cells in this manner, the exhaust gas is opened to the upstream side of the cell 5. The particulate matter in the exhaust gas flows into the surface of the partition wall 4 and the pores when the gas passes through the partition wall 4. It is collected.

  Moreover, in this embodiment, about the cell 5 by which the one end side is the slit part 11, all the other ends are plugged so that the Y range expanded in FIG. 2 may be shown. That is, at the end opposite to the end where the slit 11 is open, the sealing portion 6 is continuously formed corresponding to the slit 11 extending in the direction perpendicular to the axial direction Z. .

  In addition to the above configuration, as shown in an end view corresponding to the end view taken along the line AA in FIG. 4, a non-adhesive material filling layer 8 is formed in the slit portion 11 by a filler that is not bonded to the filter body. It can be set as the filter main body 1b of the structure. Note that, as the non-adhesive filler, a material rich in elasticity such as ceramic fiber is suitable for suppressing vibration of the cell assembly 10. In addition, when the filter body is formed of a material having a high coefficient of thermal expansion such as alumina ceramics, in order to obtain a sufficient effect that the free thermal expansion of the cell assembly 10 is not hindered by the filler, the slidability is good and the resistance is high. It is desirable to use a filler having excellent wear properties. As such a filler, a ceramic sintered body formed in a sheet shape having a size to be fitted into the slit portion 11 can be exemplified.

  The filter main bodies 1a and 1b of the gas purification filter of the present embodiment can be manufactured by the following manufacturing method. That is, as shown in FIG. 5A, the manufacturing method of the filter body 1a is an unfired ceramic material that becomes a porous body by firing and is partitioned by partition walls extending in a single axial direction Z. A molding step P1 for extruding a molded body of a non-joined and integral filter body comprising a plurality of formed cells, and an axial direction from one end of the molded body of the filter body toward the other end without reaching the other end A cutting step P2 that forms a slit portion 11 that opens at one end and extends toward the other end by cutting the filter main body in parallel with Z and cutting the partition wall, and the filter main body through the cutting step P2. 1 includes a plugging step P3 for sealing one end of the cell 5 and a firing step P4 for firing the molded body of the filter body that has undergone the plugging step P3.

  More specifically, in the molding step P1, a molded body having a shape in which the cross-sectional shape excluding the sealing portion 6 from the cross section shown in FIG.

  Next, in the cutting step P2, from the one end of the molded body to the other end, it is cut in parallel to the partition walls that partition the cells in the axial direction Z and the direction perpendicular to the axial direction. That is, the cylindrical shaped body is cut so as to be vertically divided, but at this time, it is not cut until reaching the other end, and an uncut portion is left on the other end side. Thus, the space formed by cutting away the partition wall becomes the slit portion 11 that opens to the end portion on the side where cutting is started. In this embodiment, the case where the slit portion 11 having a width corresponding to two cells is formed by cutting away the partition walls corresponding to two cells is illustrated.

  Here, in this embodiment, when the manufactured gas purification filter is used, the cutting of the molded body is started from the end portion Ed which is the downstream side of the gas flow. In the cutting step P2, in the direction perpendicular to the axial direction Z, the molded body is cut from end to end. Such cutting can be performed, for example, by cutting the molded body using a cutter having a rotary blade having a diameter larger than the diameter of the molded body.

  In this way, the integrated filter portion Cf is formed on the end Eu side that should be the upstream side of the gas flow, and the separation filter portion Sf that includes the slit portion 11 is the end portion Ed side that should be the downstream side of the gas flow A molded body formed in the above is obtained. Next, one end of the cell 5 is plugged in a plugging step P3. At this time, the cells 5 are plugged so as to be alternately sealed on one end side, but all the cells 5 that become the slit portions 11 on the end Ed side are plugged on the end Eu side. Subsequently, by firing the molded body in the firing step P4, the molded body having the above-described configuration is sintered and a sintered body of the filter body 1a is obtained.

  Further, as described above with reference to FIG. 4, when manufacturing the filter main body 1 b further including the non-adhesive material filling layer 8, as shown in FIG. 5B, the non-adhesive material filling step is performed after the firing step P <b> 4. P5 may be provided.

  In the above, the case where the plugging process P3 is performed subsequent to the cutting process P2 is illustrated, but as shown in FIGS. 5C and 5D, the plugging process P2 is performed following the molding process P1. 'May be performed, and then the cutting step P3' may be performed.

  The filter bodies 1a and 1b thus obtained are canned while covering the outer peripheral surface with a sheet material made of heat-resistant material having elasticity, and installed in the exhaust gas flow passage with the axial direction Z aligned with the exhaust gas flow direction. By doing so, it can be used as a gas purification filter of the present embodiment.

  According to the gas purification filter having the above configuration manufactured by the above manufacturing method, in the separation type filter unit Sf, each cell assembly 10 separated through the slit unit 11 is moved by the adjacent cell assembly 10. Since it is possible to expand and contract without being restricted, even if the temperature distribution becomes non-uniform and the coefficient of thermal expansion differs among the cell assemblies 10, the individual cell assemblies 10 have different thermal expansion coefficients. High degree of freedom for thermal expansion. Thereby, it can suppress that a crack generate | occur | produces in the filter main bodies 1a and 1b resulting from the difference in a thermal expansion coefficient.

  Further, since the filter main bodies 1a and 1b are non-joined and all the cells have a strong integrated structure via the integrated filter portion Cf, the separated filter portion Sf has a plurality of separated cell assemblies 10 separated from each other. Even when the filter main body is divided, the shape of the entire filter main body 1a, 1b is easily maintained stably.

  In addition, in the present embodiment, the filter main bodies 1a and 1b are cut in parallel to the partition 4 in the cutting step P2, so that the slit portion is parallel to the partition 4 in both the axial direction Z and the direction perpendicular to the axial direction Z. 11 extends, and the slit portion 11 does not intersect the partition 4. Thereby, the partition 4 which exists along the slit part 11 can fully exhibit a filtering action.

  Further, the integrated filter Cf is provided on the upstream end Eu side where the temperature is not so high during the regeneration process of the DPF and the temperature difference is not large, so that it can freely expand and contract for each part. Even if not, cracks due to thermal stress are unlikely to occur. On the other hand, the temperature may be extremely high during the regeneration process, and the downstream end portion Ed side on which the temperature difference is likely to be large is the separation type filter portion Sf, so that each cell assembly 10 has its own thermal expansion coefficient. Accordingly, the thermal expansion can be freely performed, and the generation of thermal stress can be suppressed.

  In addition, each cell assembly 10 separated in the separation type filter portion Sf is a so-called “cantilevered” configuration that is integrated with the other cell assembly 10 only at one end side, so that it easily vibrates. If the slit material 11 is filled with a filler like the filter main body 1b, the vibration of each cell assembly 10 can be effectively reduced.

  In addition, since the filler filled in the slit portion 11 is not bonded to the filter body 1b, each cell assembly 10 can be freely thermally expanded at a coefficient of thermal expansion corresponding to each temperature. The effect is not hindered by the filler.

  Moreover, the sealing part 6 is formed in the cell 5 in which the edge part Ed side becomes the slit part 11 by cutting off the partition wall 4 on the edge part Eu side. Thereby, the gas flowing in from the cell 5 opened on the end Eu side does not flow through the slit part 11 without passing through the partition wall 4, and the particulate matter is not collected and collected outside. Leakage is prevented. In addition, when the slit part 11 is filled with the filler like the filter main body 1b, the other end of the cell 5 in which one end side is the slit part 11 by using a material that exhibits a filtering action as the filler. Even if is not plugged, particulate matter can be collected by the filler.

  It should be noted that the length n in the axial direction Z of the slit portion 11 is required not to be too short in order to effectively exhibit the action of thermally expanding each cell assembly 10 freely. On the other hand, when the length n in the axial direction Z of the slit portion 11 is too long, the plurality of cell assemblies 10 can be integrated with each other through the integrated filter portion Cf, and the overall shape of the filter bodies 1a and 1b can be maintained. It becomes difficult. From this point of view, the length n in the axial direction Z of the slit portion 11 depends on the size of the cell, the thickness of the partition wall, etc., but is 9/9 of the length N in the axial direction Z of the filter bodies 1a and 1b. 10 to 1/2 is preferable.

  In the above, the case where the cutting step P2 is performed prior to the firing step P4 is exemplified, but as a manufacturing method of another embodiment, a manufacturing method in which the cutting step is performed after the firing step can be mentioned. That is, as shown in FIG. 6 (a), this manufacturing method is an unfired ceramic material that becomes a porous body by firing, and is divided into a plurality of partition walls that extend in a single axial direction. A molding step T1 for extruding a molded body of a non-joint and integral structure filter body including cells, a plugging step T2 for sealing one end of the cells in the molded body, and firing the sintered body by sintering the molded body. A firing step T3 to be obtained, and a slit portion that opens at one end and extends toward the other end are formed by cutting without cutting to the other end from one end to the other end in the axial direction of the sintered body. Cutting step T4.

  Further, in this manufacturing method, in the cutting step T4, the sintered body can be cut parallel to the partition walls in the axial direction and in a direction perpendicular to the axial direction so that the slit portions do not intersect the partition walls. Furthermore, in the cutting step T4, the sintered body of the filter body can be cut from the end portion that should be the downstream side of the gas flow toward the end portion that should be the upstream side of the gas flow.

  Also by such a manufacturing method, the filter main body 1a having the above-described configuration that exhibits the above-described effects can be manufactured. Further, as shown in FIG. 6 (b), by performing the non-adhesive material filling step T5 after the cutting step T4, as shown in FIG. 4, the filter body 1b further comprising the non-adhesive material filling layer 8 is manufactured. can do.

  In addition, when performing a cutting process prior to a baking process as shown in FIG. 5, since it cut | disconnects in the step of a molded object, the load concerning a cutting blade etc. is small and cutting | disconnection is easy. On the other hand, when the cutting process is performed after the firing process as shown in FIG. 6, the cutting blade is loaded more heavily than the cutting body in order to cut the sintered body. There are advantages such that clogging is less likely to occur and the cut surface is less likely to be deformed because deformation is less likely to occur in the portion to be cut.

  The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the above-described embodiments, and various improvements can be made without departing from the scope of the present invention as described below. And design changes are possible.

  For example, in the above description, the case where the filter unit 1a is divided into nine cell assemblies 10 by providing the slit portion 11 so as to divide the square circumscribing the circular cross section of the filter body 1a into nine parts has been illustrated and described. The number and position of the portions 11 are not limited to this. Specifically, even in the case of nine divisions, as shown in FIG. 7A, the interval between the slit portions 11 is reduced near the center portion in the radial direction that is the highest temperature during the regeneration process. Thus, it can be set as the filter main body 1c in which the slit part 11 was provided. By adopting such a configuration, heat is easily released through the slit portion 11, and the volume of the cell assembly 10 at a portion having a large coefficient of thermal expansion due to high temperature is reduced, so that thermal expansion can be performed more freely. .

  Alternatively, as shown in FIG. 7B, the slit portion 11 may be provided so that the cell assembly 10 divided into four equal parts is formed. By adopting such a configuration, the cutting process P2 is simplified with a small number of times of cutting, and heat dissipation through the slit portion 11 is promoted in the central portion in the radial direction that becomes the highest temperature during the regeneration process. The

  Moreover, in the above, the case where the slit portion 11 is opened so as to penetrate the filter body in the direction perpendicular to the axial direction Z is exemplified, but not limited thereto, as shown in FIG. In a direction in which the slit portion 11 is perpendicular to the axial direction Z, the filter body 1e may not be penetrated.

  Furthermore, although the case where the outer shape is a columnar shape is illustrated as the filter main bodies 1a and 1b, the shape is not limited thereto, and a prismatic columnar shape or an elliptical columnar shape can be used.

  In addition, in the above, the case where the gas purification filter of the present invention is applied to a DPF that purifies gas discharged from a diesel engine is exemplified, but the present invention is not limited to this and is used in other internal combustion engines, steam turbines, and the like. The present invention can be widely applied to gas purification filters that are used, that is, gas purification filters that are sometimes used at high temperatures.

1a, 1b, 1c, 1d, 1e Filter body 4 Partition wall 5 Cell 8 Non-adhesive material filled layer 10 Cell assembly 11 Slit part Cf Integrated filter part Sf Separable filter part Eu End part Ed gas to be upstream of gas flow Ends P1 and T1 to be downstream of the flow forming process P2, P3 ′, T4 cutting process P4, T3 firing process P5, T5 non-adhesive filling process

Japanese Patent No. 3121497

Claims (8)

A gas purification filter that is disposed in a gas flow path and collects substances in the gas,
A non-joint, monolithic filter body comprising a plurality of cells that are formed of porous ceramics sintered bodies and are partitioned by partition walls extending in a single axial direction;
A gas purification filter comprising: a slit portion that opens at one end of the filter body and extends toward the other end without reaching the other end of the filter body. 2. The gas purification filter according to claim 1, wherein the slit portion extends in the axial direction in parallel with the partition wall, and extends in a direction perpendicular to the axial direction in parallel with the partition wall. 3. The gas purification filter according to claim 1, wherein the slit portion is opened at an end portion to be a downstream side of gas flow in the filter body. The gas purification filter according to any one of claims 1 to 3, wherein a non-adhesive filler layer is formed in the slit portion by a filler not bonded to the filter body. . A method for producing a gas purification filter that is disposed in a gas flow path and collects a substance in a gas,
An unfired ceramic material that becomes a porous body when fired, and extrudes a non-joint, integral structure filter body with multiple cells that are partitioned by partition walls extending in a single axial direction. Molding process to mold;
Before or after firing the molded body, it cuts without reaching the other end from one end in the axial direction and cuts the partition, thereby opening at the one end and extending toward the other end. A cutting step for forming the slit portion;
A gas purification filter manufacturing method comprising: a firing step after the cutting step or prior to the cutting step, firing the molded body to obtain a sintered body. 6. The gas purification according to claim 5, wherein in the cutting step, the slit portion is cut in parallel to the partition wall in the axial direction and in a direction perpendicular to the axial direction so as not to intersect the partition wall. A method for manufacturing a filter. The gas purification filter according to claim 5 or 6, wherein, in the cutting step, the gas purification filter is cut from an end portion to be a downstream side of the gas flow toward an end portion to be an upstream side of the gas flow. Manufacturing method. 8. The method according to claim 5, further comprising a non-adhesive material filling step of filling the slit portion with a filler without adhering to the filter body after the baking step. 9. A method for producing the cleaning filter as described.

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