JP4465792B2 - Exhaust gas purification catalytic converter, diesel particulate filter system, and manufacturing method thereof - Google Patents

Description

[0001]
【Technical field】
The present invention relates to a diesel particulate filter system, a catalytic converter for exhaust gas purification, and a method for manufacturing the same, and more particularly to a method for assembling a holding seal material in a metal shell.
[0002]
[Prior art]
A diesel particulate filter (hereinafter also referred to as “DP filter”) system installed in a diesel engine vehicle is composed of a ceramic DP filter for capturing diesel particulates and a metal shell for accommodating the same. . A holding seal material for holding the DP filter is interposed between the DP filter and the metal shell. The holding sealing material is made of an inorganic fiber mat.
[0003]
[Problems to be solved]
However, the holding sealing material has cushioning properties and is bulky. For this reason, there is a possibility that the mounting operation of the holding sealing material may be hindered when the DP filter is mounted in the metal shell together with the holding sealing material.
Therefore, it is conceivable to reduce the thickness of the inorganic fiber mat by impregnating the holding sealing material with a binder. However, in this case, the binder may burn out and the amount of exhaust gas may increase, and the exhaust gas regulation value cannot be satisfied.
Further, the exhaust gas-purifying catalytic converter has a configuration in which a catalyst holder is mounted in a metal shell via a holding sealing material, and has the same problem as the DP filter system.
[0004]
The present invention intends to provide a diesel particulate filter system, an exhaust gas purification catalytic converter, and a manufacturing method thereof, which can be easily mounted in a metal shell of a DP filter or a catalyst holder and have a small amount of exhaust gas. It is.
[0005]
[Means for solving problems]
The invention of claim 1 comprises a diesel particulate filter, a metal shell covering the outside of the diesel particulate filter, and a holding sealing material disposed between the diesel particulate filter and the metal shell. A method for manufacturing a diesel particulate filter system comprising:
Coating a diesel particulate filter with a holding sealing material to form a covering;
Inserting the covering into a pipe-shaped metal shell,
A spiral groove is formed on the inner wall of the metal shell, and when the metal shell is inserted into the cover, the cover is screwed into the metal shell while rotating in the spiral direction of the spiral groove of the metal shell. Thus, the method of manufacturing a diesel particulate filter system is characterized in that the holding sealing material is guided along the spiral groove and press-fitted .
[0006]
In the present invention, the DP filter is covered with a holding sealing material, which is screwed into a metal shell and press-fitted. Since the spiral groove is formed in the metal shell, the DP filter is guided into the metal shell along the spiral groove together with the holding seal material. Therefore, the force required for screwing the DP filter and the holding sealing material is reduced. Therefore, according to the present invention, the DP filter and the holding sealing material can be mounted in the metal shell with a small force.
In the present invention, it is not necessary to make the holding sealing material impregnated with a binder to reduce the thickness. In addition, the organic components discharged from the holding sealing material in the exhaust gas can be eliminated, which is excellent from the viewpoint of environmental conservation.
[0007]
The holding sealing material is preferably an inorganic fiber mat that is not impregnated with a binder. Thereby, the metal shell holding force of the holding sealing material increases. Further, since the binder is not included, the organic component is not discharged as exhaust gas from the holding sealing material.
[0008]
The inorganic fiber mat preferably contains alumina and silica. Thereby, the heat resistance of the inorganic fiber mat is improved.
In particular, the inorganic fiber mat preferably contains 70 to 100% by weight of alumina. Thereby, the elastic force at the time of high temperature becomes high, and the force holding the DP filter increases. Further, these properties can be sufficiently exhibited even at a high temperature of 900 to 950 ° C., and can sufficiently cope with the recent trend toward high temperatures of internal combustion engines.
[0009]
The inorganic fiber mat is preferably subjected to needle punching. As a result, the fibers are entangled with each other, the elastic force is increased, and the force for holding the DP filter is improved.
[0010]
As in the invention of claim 3, the bulk density of the holding sealing material before being inserted into the metal shell is preferably 0.05 to 0.2 g / cm ³ . Is less than 0.05 g / cm ^3, may be difficult to coat the DP filter by the holding sealing material, if it exceeds 0.2 g / cm ^3, the repulsive force decreases broken fibers, DP filters There is a risk that the force to hold the will decrease.
[0011]
As in the invention of claim 4, it is preferable that the filling density of the holding sealing material after being inserted into the metal shell is 0.20 to 0.60 g / cm ³ . If it is less than 0.20 g / cm ³ , the holding force of the diesel particulate filter by the holding sealing material may be reduced. On the other hand, when it exceeds 0.60 g / cm ³ , the fiber breaks and the repulsive force decreases, and the force for holding the DP filter may decrease.
[0012]
The ratio of the thickness after insertion to the thickness of the holding sealing material before insertion into the metal shell is preferably 1/5 to 1/2. As a result, it is possible to secure an appropriate force for holding the DP filter.
[0013]
The invention of claim 5 comprises a diesel particulate filter, a metal shell covering the outside of the diesel particulate filter, and a holding seal material disposed between the diesel particulate filter and the metal shell,
A spiral groove formed along the insertion direction of the diesel particulate filter is formed on the inner wall of the metal shell, and the holding seal material is guided and press-fitted along the spiral groove. This is a diesel particulate filter system.
[0014]
In the present invention, since the spiral groove is formed in the inner wall of the metal shell, the DP filter can be stably held in the metal shell.
[0015]
The spiral groove in the inner wall of the metal shell is formed along the insertion direction of the diesel particulate filter . As a result, the DP filter can be held more stably.
[0016]
According to a sixth aspect of the present invention, there is provided an exhaust gas purifying apparatus comprising a catalyst holding body, a metal shell covering the outside of the catalyst holding body, and a holding sealing material disposed between the catalyst holding body and the metal shell. A method of manufacturing a catalytic converter for a vehicle,
Coating the catalyst holder with a holding sealing material to form a covering;
Inserting the covering into a pipe-shaped metal shell,
A spiral groove is formed on the inner wall of the metal shell, and when the metal shell is inserted into the cover, the cover is screwed into the metal shell while rotating in the spiral direction of the spiral groove of the metal shell. Thus , the holding sealing material is guided along the spiral groove and press-fitted , whereby the exhaust gas purifying catalytic converter is manufactured.
[0017]
In the present invention, an exhaust gas purifying catalytic converter is manufactured using a catalyst holder instead of the DP filter in the method for manufacturing a diesel particulate filter system.
In the present invention, the catalyst holding body is covered with a holding sealing material, and this is screwed into a metal shell having a spiral groove and press-fitted. Therefore, the catalyst holding body is guided into the metal shell along the spiral groove together with the holding sealing material. Therefore, according to the present invention, the catalyst holder and the holding sealing material can be mounted in the metal shell with a small force.
In the present invention, it is not necessary to reduce the thickness by impregnating the holding sealing material with a binder, which is excellent from the viewpoint of environmental protection.
[0018]
As in the invention of claim 7, the holding sealing material is preferably an inorganic fiber mat not impregnated with a binder. Thereby, the metal shell holding force of the holding sealing material increases. Further, since the binder is not included, the organic component is not discharged as exhaust gas from the holding sealing material.
[0019]
As in the invention of claim 8 , the bulk density of the holding sealing material before being inserted into the metal shell is preferably 0.05 to 0.2 g / cm ³ . Is less than 0.05 g / cm ^3, may be difficult to coat the catalyst retainer by the holding sealing material, if it exceeds 0.2 g / cm ^3, the repulsive force decreases broken fibers, catalysts There is a possibility that the force for holding the holding body is reduced.
[0020]
As in the ninth aspect of the invention, the filling density of the holding sealing material after being inserted into the metal shell is preferably 0.20 to 0.60 g / cm ³ . If it is less than 0.20 g / cm ³ , the force for holding the catalyst holder by the holding sealing material may be reduced. On the other hand, if it exceeds 0.60 g / cm ³ , the fiber breaks and the repulsive force decreases, and the force for holding the catalyst holding body may decrease.
[0021]
The invention of claim 10 comprises a catalyst holding body, a metal shell covering the outside of the catalyst holding body, and a holding sealing material disposed between the catalyst holding body and the metal shell,
A spiral groove formed along the insertion direction of the catalyst holder is formed on the inner wall of the metal shell, and the holding sealing material is guided along the spiral groove and press-fitted. It is a catalytic converter for exhaust gas purification.
[0022]
In this exhaust gas purifying catalytic converter, since the spiral groove along the insertion direction of the catalyst holder is formed on the inner wall of the metal shell, the catalyst holder can be stably held in the metal shell.
[0023]
The spiral groove in the inner wall of the metal shell is formed along the insertion direction of the catalyst holder . As a result, the DP filter can be held more stably.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1
A method for manufacturing a DP filter system according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1, the DP filter system 5 of this example includes a DP filter 3 for capturing diesel particulates, a metal shell 2 that covers the side surface of the DP filter 3, and a DP filter 3 and a metal shell 2. It consists of the holding | maintenance sealing material 1 arrange | positioned between.
[0025]
The metal shell 2 is a cylindrical body (pipe) having a diameter of 141 mm and an inner diameter of 138 mm, and a spiral groove 21 having a width of 1 mm and a depth of 0.3 mm is formed on the inner wall thereof. The amount of progress in the direction of the spiral axis per rotation of the spiral groove 21 is 10 mm. Further, as shown in FIG. 2, a spiral convex portion 22 corresponding to the spiral groove 21 formed on the inner wall is formed on the surface of the metal shell 2.
[0026]
The holding sealing material 1 is composed of 70% by weight alumina fiber and 30% by weight silica fiber. The filling density of the holding sealing material 1 in the metal shell 2 is 0.3 g / cm ³ and the thickness is 4 mm.
[0027]
The DP filter 3 is made of cordierite, which is a kind of ceramic. As shown in FIG. 3, the DP filter 3 is a cylindrical body having a honeycomb structure and has a diameter of 130 mm. The DP filter 3 is a honeycomb structure composed of an aggregate of a large number of cells that are open on the upstream side or downstream side of the exhaust system and closed on the other side. The DP filter 3 allows the exhaust gas to pass from the upstream opening cell 31 to the downstream opening cell 32 through the porous cell wall. At this time, the diesel particulates contained in the exhaust gas are captured by the cell walls, and the exhaust gas is purified. The captured diesel particulates are burned off by an ignition device (not shown).
The DP filter system 5 is provided in the middle of the exhaust pipe 91 of the diesel engine 9.
[0028]
Next, a method for manufacturing the DP filter system of this example will be described.
First, 70% by weight of alumina fibers and 30% by weight of silica fibers are mixed to form a web. A needle punching process is applied to the web. Thereby, the fibers in the web are entangled with each other, and the holding sealing material 1 made of the inorganic fiber mat is formed. At this time, the thickness of the holding sealing material 1 is 12 mm, and the filling density is 0.1 g / cm ³ .
[0029]
Next, as shown in FIG. 4 (a), the holding sealing material 1 is cut into a long body and engaged with each other when the outer periphery of the DP filter 3 is wound around both ends thereof. The concave portion 11 and the convex portion 12 are formed.
Next, as shown in FIG. 4B, the holding sealing material 1 is wound around the side surface of the DP filter 3, and the concave portion 11 and the convex portion 12 are abutted to obtain the covering 4.
Further, as shown in FIG. 4C, a spiral groove 21 is formed in the inner wall of the pipe-shaped metal shell 2.
[0030]
Next, as shown in FIG. 5, the cover 4 is screwed into the metal shell 2 while being rotated in the spiral traveling direction of the spiral groove 21 of the metal shell 2.
1 and 2, the DP filter 3 is attached to the metal shell 2 via the holding sealing material 1.
After that, as shown in FIG. 3, the flanges 29 for connecting to the exhaust system 91 are formed by squeezing the opening portions at both ends of the metal shell 2.
Thus, the DP filter system 5 of this example is obtained.
[0031]
In the present invention, as shown in FIG. 5, the DP filter 3 is covered with the holding sealing material 1, and this is screwed into the metal shell 2 and press-fitted. Since the spiral groove 21 is formed in the metal shell 2, the DP filter 3 is guided into the metal shell 2 along the spiral groove 21 together with the holding sealing material 1. Therefore, the force required for screwing the DP filter 3 and the holding sealing material 1 is reduced. Therefore, according to this example, the DP filter 3 and the holding sealing material 1 can be mounted in the metal shell 2 with a small force.
In addition, it is not necessary to reduce the thickness by impregnating the holding sealing material with a binder.
[0032]
Embodiment 2
In the method of manufacturing the exhaust gas purifying catalytic converter of this example, a catalyst holding body is used instead of the DP filter of the first embodiment.
The catalyst holder is made of ceramics and has a honeycomb structure, and carries a catalyst such as platinum for purifying exhaust gas. In other respects, the same manufacturing process as in Embodiment 1 is performed.
[0033]
The catalytic converter for exhaust gas purification is arranged in the middle of the exhaust pipe of a gasoline engine. When the exhaust gas is passed through the catalyst holder, exhaust gas components such as HC are purified by the catalytic action in the catalyst holder.
Also in this example, the catalyst holder can be easily inserted into the metal shell, and the holding sealing material holds the catalyst holder with an appropriate surface pressure.
[0034]
【The invention's effect】
According to the present invention, it is possible to provide a diesel particulate filter system and a catalytic converter for purifying exhaust gas, and a method for producing them, which facilitate the mounting operation of the DP filter or catalyst holder in the metal shell and reduce the amount of exhaust gas. Can do.
[Brief description of the drawings]
FIG. 1 is a partially cutaway perspective view showing an internal structure of a DP filter system according to a first embodiment.
FIG. 2 is a perspective view of a DP filter system according to a first embodiment.
3 is a cross-sectional explanatory view of a DP filter system in Embodiment 1. FIG.
FIGS. 4A to 4C are explanatory views (a) to (c) illustrating a method for manufacturing a DP filter in Embodiment 1. FIG.
FIG. 5 is an explanatory view showing a DP filter manufacturing method following FIG. 4;
[Explanation of symbols]
1. . . Holding sealing material,
2. . . Metal shell,
21. . . Spiral groove,
22. . . Convex part,
3. . . DP filter,
4). . . Covering,
5). . . DP filter system,

Claims (10)

A diesel particulate filter system comprising a diesel particulate filter, a metal shell that covers the outside of the diesel particulate filter, and a holding seal material disposed between the diesel particulate filter and the metal shell. A manufacturing method,
Coating a diesel particulate filter with a holding sealing material to form a covering;
Inserting the covering into a pipe-shaped metal shell,
A spiral groove is formed in the inner wall of the metal shell, and when the metal shell is inserted into the cover, the cover is screwed into the metal shell while rotating in the spiral direction of the spiral groove of the metal shell. Thus, the method for producing a diesel particulate filter system, wherein the holding sealing material is guided along the spiral groove and press-fitted .   2. The method for manufacturing a diesel particulate filter system according to claim 1, wherein the holding sealing material is an inorganic fiber mat not impregnated with a binder. ^{3. The} method for manufacturing a diesel particulate filter system according to claim 1, wherein the bulk density of the holding sealing material before being inserted into the metal shell is 0.05 to 0.2 g / cm ³ . The diesel particulate according to any one of claims 1 to 3, wherein a filling density of the holding sealing material after being inserted into the metal shell is 0.20 to 0.60 g / cm ^3. A method for manufacturing a filter system. A diesel particulate filter, a metal shell covering the outside of the diesel particulate filter, and a holding seal material disposed between the diesel particulate filter and the metal shell,
A spiral groove formed along the insertion direction of the diesel particulate filter is formed on the inner wall of the metal shell, and the holding seal material is guided and press-fitted along the spiral groove. Diesel particulate filter system.   A method for producing an exhaust gas purifying catalytic converter comprising a catalyst holder, a metal shell covering the outside of the catalyst holder, and a holding sealing material disposed between the catalyst holder and the metal shell. There,
  Coating the catalyst holder with a holding sealing material to form a covering;
  Inserting the covering into a pipe-shaped metal shell,
  A spiral groove is formed in the inner wall of the metal shell, and when the metal shell is inserted into the cover, the cover is screwed into the metal shell while rotating in the spiral direction of the spiral groove of the metal shell. Thus, the method for producing an exhaust gas-purifying catalytic converter, wherein the holding sealing material is guided along the spiral groove and press-fitted.   7. The method for producing a catalytic converter for exhaust gas purification according to claim 6, wherein the holding sealing material is an inorganic fiber mat not impregnated with a binder.   In Claim 6 or 7, the bulk density of the holding sealing material before inserting into the metal shell is 0.05 to 0.2 g / cm. ³ A method for producing an exhaust gas-purifying catalytic converter.   The filling density of the holding sealing material after inserting into the metal shell according to any one of claims 6 to 8, is 0.20 to 0.60 g / cm. ³ A method for producing an exhaust gas-purifying catalytic converter.   A catalyst holding body, a metal shell covering the outside of the catalyst holding body, and a holding sealing material disposed between the catalyst holding body and the metal shell,
  A spiral groove formed along the insertion direction of the catalyst holder is formed on the inner wall of the metal shell, and the holding sealing material is guided along the spiral groove and press-fitted. Catalytic converter for exhaust gas purification.

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