JP6270883B2 - Exhaust gas purification device for internal combustion engine - Google Patents

Description

  The present invention relates to an exhaust emission control device for an internal combustion engine.

  2. Description of the Related Art Conventionally, there has been known an exhaust purification device for an internal combustion engine that includes a honeycomb carrier having a filter function on which an exhaust purification catalyst is supported, and a cylindrical case member that stores the honeycomb carrier via a holding member. ing. As the honeycomb carrier, a so-called wall flow type honeycomb carrier in which inflow openings and outflow openings of adjacent cells are alternately sealed is used. When the honeycomb carrier is stored in the case member, it is important to securely hold the honeycomb carrier in the case member.

  As a technique for holding the honeycomb carrier in the case member, a technique using a mesh ring or the like is common. However, when a mesh ring or the like is used, the entire filter cannot be used efficiently, and there is a problem that the effective capacity of the filter and the exhaust purification performance are reduced. On the other hand, a technique is known in which a protrusion projecting radially outward is provided on at least a part of the outer peripheral side surface of the honeycomb carrier (for example, see Patent Documents 1 to 3). According to this technology, the convex portion functions as a locking portion, so that the honeycomb carrier can be reliably held in the case member without using parts such as a mesh ring, and a sufficient effective filter capacity and exhaust purification performance can be obtained. Can be secured.

Japanese Patent No. 5053224 JP 2013-144554 A JP 2014-64978 A

  By the way, since the said convex part is formed by grinding the outer peripheral side surface of a honeycomb support | carrier, a manufacturing process is complicated and manufacturing cost increases. Therefore, the present inventor provides a sufficient filter with a simple structure in which an inclined portion or a stepped portion is provided in the outer peripheral sealing portion of the honeycomb carrier, and the inclined portion or the stepped portion is hooked on the inner wall of the case member via the holding member. It has been found that the honeycomb carrier can be reliably held in the case member while ensuring the effective capacity and the exhaust purification performance.

  However, in this case, depending on the positional relationship between the sealing member and the holding member in the inclined portion or the stepped portion, the particulate matter (PM) contained in the exhaust gas or the ash (Ash) of the incombustible component is downstream of the honeycomb carrier. There was a risk of leakage. Further, when the end of the holding member in the central axis direction of the honeycomb carrier protrudes from the end surface of the honeycomb carrier in the central axis direction, exhaust directly hits the end of the holding member, thereby There was a risk of wind erosion.

  The present invention has been made in view of the above, and its purpose is to ensure that the honeycomb carrier can be reliably held in the case member while ensuring a sufficient effective filter capacity and exhaust purification performance, and to prevent particulate matter and ash. An object of the present invention is to provide an exhaust emission control device for an internal combustion engine that can be reliably captured and can suppress wind erosion of a holding member.

  In order to achieve the above object, the present invention provides an exhaust emission control device for purifying exhaust gas of an internal combustion engine, which is provided in an exhaust passage (eg, an exhaust pipe described later) of an internal combustion engine (eg, an engine described later). A plurality of cells extending from an inflow end surface (for example, an inflow side end surface 110a described later) to an outflow side end surface (for example, an outflow side end surface 110b described later) and serving as an exhaust passage are partitioned by porous partition walls. Via a columnar honeycomb carrier (for example, a honeycomb carrier 11 described later), an exhaust purification catalyst (for example, a three-way catalyst described later) supported on the honeycomb carrier, and a holding member (for example, a holding member 13 described later). A cylindrical case member (for example, a case member 12 to be described later) for storing the honeycomb carrier, and the honeycomb carrier has outer peripheries of both end surfaces in a direction of a central axis (for example, a central axis X to be described later). And an outer peripheral portion having a stepped portion (for example, an inclined portion 112a, 112b described later) or a stepped portion formed so that a cross-sectional area perpendicular to the central axis direction increases toward the outer peripheral edge side thereof (for example, described later) An outer peripheral portion P) and a central portion (for example, a central portion C described later) surrounded by the outer peripheral portion, and the outer peripheral portion is hooked on the inner wall of the case member via the holding member. Held in the case member, the center portion is alternately sealed with the inflow side opening and the outflow side opening of the adjacent cell, while the inclined portion or the stepped portion of the outer peripheral portion is adjacent to the cell. The inflow side opening portion and the outflow side opening portion are alternately sealed with a sealing region (for example, a sealing region SR described later), and an opening that is disposed on the outer periphery of the sealing region and is not sealed. Region (for example, an opening described later) The holding member has a position in the central axis direction of at least one of an upstream end (for example, an upstream end 131 described later) and a downstream end (for example, a downstream end 132 described later) of the holding member. An exhaust purification device for an internal combustion engine (for example, an exhaust purification device 1 to be described later) disposed so as to overlap with the position in the central axis direction of the sealing region in the inclined portion or the stepped portion.

In the present invention, inclined portions or stepped portions are formed at both ends in the central axis direction of the outer peripheral portion of the honeycomb carrier in a direction in which a cross-sectional area perpendicular to the central axis direction increases toward the outer peripheral edge side. That is, the inclined portion or the step portion is formed in a direction in which the length in the central axis direction on the outer peripheral edge of the honeycomb carrier is reduced. Then, the honeycomb carrier is held in the case member such that the outer peripheral portion on which the inclined portion or the stepped portion is formed is caught on the inner wall of the case member via the holding member.
Accordingly, the honeycomb carrier can be reliably held in the case member by a simple structure in which the outer peripheral portion of the honeycomb carrier in which the inclined portion or the step portion is formed is hooked on the inner wall of the case member via the holding member. In addition, since there is no need to use parts such as a mesh ring, a sufficient effective filter capacity and exhaust purification performance can be ensured.

Further, in the present invention, the inclined portion or the stepped portion is disposed on the outer periphery of the sealing region where the inflow side opening portion and the outflow side opening portion of the adjacent cells are alternately sealed, and the plugging region is sealed. And an open region that is not marked. And a holding member is arrange | positioned so that the position of the central-axis direction of at least one of the upstream end and downstream end of a holding member may overlap with the position of the plugging area | region in the said inclination part or level | step-difference part.
Here, in the case of sealing the entire outer peripheral portion from the viewpoint of preventing leakage of particulate matter and ash, it is necessary to form the plug deeply across the entire end surfaces of the honeycomb carrier in the central axis direction. The effective capacity is reduced. On the other hand, according to the present invention, an opening region that is not sealed is formed in the inclined portion or the step portion of the outer peripheral portion, and the opening region is configured to be surely covered with the holding member. Particulate matter and ash can be reliably captured while securing an effective volume. Further, since the upstream end and the downstream end of the holding member do not protrude from the end surface in the central axis direction of the honeycomb carrier, it is possible to suppress the exhaust from directly hitting the upstream end and the downstream end of the holding member, and the wind erosion of the holding member Can be suppressed.

  It is preferable that the holding member is arranged so that the position in the central axis direction of the upstream end thereof overlaps the position in the central axis direction of the sealing region in the inclined portion or the stepped portion.

In the present invention, the holding member is arranged so that the position in the central axis direction of the upstream end of the holding member overlaps the position in the central axis direction of the sealing region in the inclined portion or the stepped portion.
According to this invention, since the upstream end of the holding member is located in the plugged region of the inclined portion or the stepped portion, the opening region that is not sealed in the inclined portion or the stepped portion on the upstream side of the honeycomb carrier is formed by the holding member. Can be reliably covered. Therefore, particulate matter and ash do not flow into the outer peripheral portion of the honeycomb carrier, and the outer peripheral portion functions as an exhaust purification unit. Therefore, according to the present invention, more excellent exhaust purification performance can be obtained.

  The holding member is preferably arranged so that the position in the central axis direction of the downstream end thereof overlaps with the position in the central axis direction of the sealing region in the inclined portion or the stepped portion.

In this invention, the holding member is arranged so that the position in the central axis direction of the downstream end of the holding member overlaps with the position in the central axis direction of the sealing region in the inclined portion or the stepped portion.
According to the present invention, since the downstream end of the holding member is located in the plugged region of the inclined portion or the stepped portion, the opening region that is not sealed in the inclined portion or the stepped portion on the downstream side of the honeycomb carrier is formed by the holding member. Can be reliably covered. Therefore, when the particulate matter or ash flows from the outer peripheral portion on the upstream side of the honeycomb carrier, the inflowing particulate matter or ash is captured without flowing out from the outer peripheral portion on the downstream side. That is, the outer peripheral portion of the honeycomb carrier functions as a particulate matter or ash capturing portion (pocket). Therefore, according to the present invention, a more excellent filter function can be obtained, and particulate matter and ash can be captured more reliably.

  The outer peripheral portion includes a straight portion that is formed at least at one end of both ends in the central axis direction and extends in the central axis direction, the sealing region is disposed in the straight portion, and the holding member is Preferably, at least one of the upstream end and the downstream end in the central axis direction is disposed so as to overlap with the position in the central axis direction of the sealing region in the straight portion.

In the present invention, a straight portion extending in the central axis direction is formed at least at one end of both ends of the outer peripheral portion in the central axis direction, and a sealing region is disposed on the straight portion. Further, the holding member is arranged so that the position in the central axis direction of at least one of the upstream end and the downstream end of the holding member overlaps with the position in the central axis direction of the sealing region in the straight portion.
Here, normally, the position of the holding member (the position of the upper end or the lower end of the holding member) is highly likely to vary during canning. To absorb this variation, for example, the inclined length of the inclined portion formed on the outer peripheral portion is increased. However, there is a restriction from the viewpoint of holding the honeycomb carrier in the case member.
On the other hand, according to the present invention, since the outer peripheral portion has the straight portion in which the sealing region is arranged, even when the position of the holding member varies during canning, the variation can be absorbed by the straight portion. . Therefore, according to the present invention, it is more reliable that the upstream end and the downstream end of the holding member protrude from the end surface in the central axis direction of the honeycomb carrier while more reliably covering the open area that is not sealed with the holding member. Since it can avoid, the wind erosion of a holding member can be suppressed more reliably.

  According to the present invention, the honeycomb carrier can be securely held in the case member while ensuring a sufficient effective filter capacity and exhaust purification performance, particulate matter and ash can be reliably captured, and wind erosion of the holding member is suppressed. An exhaust gas purification device for an internal combustion engine that can be provided can be provided.

1 is a perspective view of an exhaust emission control device according to a first embodiment. It is an axial sectional view of the exhaust emission control device according to the first embodiment. It is an enlarged view of the upstream outer peripheral part in FIG. It is an axial sectional view of the exhaust emission control device according to the second embodiment. It is an enlarged view of the downstream outer peripheral part in FIG. It is an enlarged view of the upstream outer peripheral part in the axial sectional view of the exhaust gas purification apparatus according to the third embodiment. It is the figure which looked at the honeycomb carrier of the exhaust gas purification device according to the third embodiment from the upstream side. It is a perspective view of the upstream outer peripheral part in the honeycomb support | carrier of the exhaust gas purification apparatus which concerns on 3rd Embodiment.

  Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. In the description after the second embodiment, the same reference numerals are given to the same components as those in the first embodiment, and the corresponding components are given the same regularity to explain the configuration and effects. Omitted.

[First Embodiment]
FIG. 1 is a perspective view of an exhaust gas purification apparatus for an internal combustion engine according to the first embodiment of the present invention. An exhaust gas purification apparatus 1 for an internal combustion engine according to the present embodiment is provided in an exhaust pipe of a gasoline engine (hereinafter referred to as “engine”) as an internal combustion engine (not shown), and particulate matter in exhaust gas flowing through the exhaust pipe. (Hereinafter referred to as “PM”) and a gasoline particulate filter (hereinafter referred to as “GPF”) that captures ash (Ash) of incombustible components.

The exhaust emission control device 1 is provided in an exhaust pipe that extends downwardly along a side surface of the engine on the vehicle front side immediately below an engine (not shown). That is, the exhaust emission control device 1 is provided in the exhaust pipe in a state where the flow direction of the exhaust is directed downward.
As shown in FIG. 1, the exhaust emission control device 1 includes a honeycomb carrier 11 and a case member 12.

The honeycomb carrier 11 has a plurality of cells that extend from the exhaust inflow end face 110a to the outflow end face 110b to serve as exhaust passages, and porous partition walls that define the cells.
The honeycomb carrier 11 has a cylindrical shape with a circular cross section. However, the honeycomb carrier may be columnar, and for example, the shape of the cross section in the radial direction may be an ellipse or a shape having a plurality of arcs.
The shape of each cell is a quadrangular prism shape with a square cross section, but may be a polygonal shape, for example.

The honeycomb carrier 11 is formed of a porous refractory ceramic made of cordierite. The honeycomb carrier 11 made of cordierite can be obtained by, for example, integrally forming by extrusion molding and then firing. At the time of firing, an outer skin covering the outer peripheral side surface is simultaneously formed. Therefore, since the outer peripheral side surface of the honeycomb carrier 11 of the present embodiment is covered with the outer skin, the catalyst does not leak from the outer peripheral side surface in the catalyst supporting step, and the exhaust does not leak from the outer peripheral side surface during use.
The pore (pore) diameter and the pore (pore) ratio of the honeycomb carrier 11 are appropriately set within a range in which the partition wall functions as a filter medium for filtering PM and ash in the exhaust gas.

The honeycomb carrier 11 carries an exhaust purification catalyst for purifying the exhaust throughout. That is, the exhaust purification catalyst is carried on both the center portion C and the outer peripheral portion P described later. Specifically, a three-way catalyst that purifies HC, CO, and NOx in the exhaust is supported on the honeycomb carrier 11 of the present embodiment. As the three-way catalyst, a catalyst containing at least one noble metal among Pt, Pd and Rh is preferably used.
A more detailed structure of the honeycomb carrier 11 will be described in detail later.

The case member 12 has a circular cylindrical shape in cross section, and stores the above-described honeycomb carrier 11 therein. However, the case member 12 only needs to be cylindrical according to the shape of the honeycomb carrier 11. For example, the radial cross section may have an elliptical ring or a plurality of arc rings.
The case member 12 is made of a metal such as SUS.

The case member 12 is a clamshell type case member composed of case halves 121 and 122 that are divided into two in the circumferential direction along the central axis X direction (vertical direction in FIG. 1). As shown in FIG. 1, the case member 12 is integrally formed by butt welding the case halves 121 and 122 divided into two at the extending portions 120 and 120.
In addition, the extension parts 120 and 120 are formed by butt-welding the flanges by bending the circumferential edges of the case halves outward.

Here, FIG. 2 is an axial sectional view (a sectional view along the central axis X direction) of the exhaust gas purification apparatus 1 according to the present embodiment. In FIG. 2, the black portion indicates the plugged portion 111 in which the opening of each cell is plugged with the plugging agent (the same applies to FIG. 3 and thereafter).
As shown in FIG. 2, the honeycomb carrier 11 is stored in the case member 12 via the holding member 13. More specifically, the honeycomb carrier 11 is stored in the case member 12 in a state where the mat-like holding member 13 is wound over the entire circumference of the outer peripheral side surface.

  Further, the case member 12 has a shape along the outer shape of the honeycomb carrier 11, and both end portions in the central axis direction, that is, the exhaust inflow side end portion and the outflow side end portion are gradually contracted toward the end portions. The case inclined portions 121a and 121b are formed. That is, the case inclined portions 121a and 121b extend along inclined portions 112a and 112b of the honeycomb carrier 11 described later, respectively. Accordingly, the stored honeycomb carrier 11 is held in the case member 12 by the inclined portions 112 a and 112 b being hooked on the inner walls of the case inclined portions 121 a and 121 b of the case member 12 via the holding member 13.

  The holding member 13 is interposed between the outer peripheral side surface of the honeycomb carrier 11 and the inner wall of the case member 12 to hold the honeycomb carrier 11 in the case member 12. As the holding member 13, a material having heat resistance, vibration resistance, and sealing properties is used. Specifically, a metal mesh or the like is used in addition to ceramic fibers such as alumina fibers, silica fibers, alumina silica fibers, and ceramic glass fibers.

Next, the detailed structure of the honeycomb carrier 11 and the arrangement of the holding members 13 will be described in detail with reference to FIGS. 2 and 3.
Here, FIG. 3 is an enlarged view of the upstream outer peripheral portion in FIG. As shown in FIGS. 2 and 3, the honeycomb carrier 11 has the structure of the outer peripheral portion P in the radial direction (the direction perpendicular to the central axis X direction and the left-right direction in FIGS. 2 and 3) and the structure of the central portion C. Are different from each other.

  Specifically, the central portion C of the honeycomb carrier 11 has a columnar shape. The central portion C has a so-called wall flow structure in which cells in which the exhaust inflow side opening portion is sealed and cells in which the outflow side opening portion is sealed are alternately arranged in a checkered pattern. ing. As the plugging agent used for plugging, for example, a conventionally known one formed by mixing cordierite powder and an adhesive or the like is used.

  On the other hand, inclined portions 112a and 112b are formed over the entire circumference on the outer peripheral sides of both end faces 110a and 110b in the central axis X direction of the honeycomb carrier 11. That is, the outer peripheral portion P of the honeycomb carrier 11 includes the inclined portions 112a and 112b at both ends in the central axis X direction. These inclined portions 112a and 112b are formed by grinding or cutting the outer peripheral portion P by a manufacturing method described later.

The inclined portions 112a and 112b are configured by inclined planes that are inclined in a direction in which the length of the outer peripheral edge of the honeycomb carrier 11 in the direction of the central axis X decreases. That is, the inclined portions 112a and 112b are
At the both ends of the outer peripheral portion P of the honeycomb carrier 11 in the central axis X direction, the outer peripheral edge side is formed so as to be inclined in a direction in which the cross-sectional area perpendicular to the central axis X direction increases. Therefore, the honeycomb carrier 11 is formed such that both ends in the central axis X direction gradually reduce in diameter toward the outer side in the central axis X direction.

  Further, the length of the inclined portions 112a and 112b in the direction of the central axis X is preferably 10 mm or less. The width in the radial direction of the inclined portions 112 a and 112 b is preferably 30% or less of the diameter of the honeycomb carrier 11. Moreover, it is preferable that the inclination | tilt angles of inclination part 112a, 112b are 15-80 degrees. By satisfying these requirements, the inclined portions 112a and 112b are surely hooked to the inner walls of the case inclined portions 121a and 121b of the case member 12 via the holding member 13, so that the honeycomb carrier 11 is placed in the case member 12. Holds securely.

  As shown in FIG. 3, the inclined portions 112a and 112b are sealed in the sealing region SR in which the inflow side openings and the outflow side openings of the adjacent cells are alternately sealed, and both the inflow side and the outflow side are sealed. And an open region OR in which the cell is open. In the sealing region SR, a sealing agent similar to the sealing agent used in the wall flow structure of the central portion C described above is used.

  Further, the holding member 13 is disposed so that the position of the upstream end 131 in the central axis X direction overlaps the position of the sealing region SR in the inclined portion 112a in the central axis X direction. That is, in the central axis X direction, the upstream end 131 of the holding member 13 is disposed within the range of the sealing region SR of the inclined portion 112a. As a result, the opening region OR of the inclined portion 112 a is reliably covered with the holding member 13, while the upstream end 131 of the holding member 13 does not protrude from the inflow side end surface 110 a of the honeycomb carrier 11.

  In the present embodiment, the position of the downstream end 132 of the holding member 13 in the central axis X direction is the position of the upstream end of the inclined portion 112b. That is, the opening region OR of the inclined portion 112b is not covered with the holding member 13, and the exhaust gas flowing into the outer peripheral portion P from the upstream side flows out from the opening region OR of the inclined portion 112b. Thereby, the outer peripheral part P functions as an exhaust gas purification part.

  Next, a method for manufacturing the exhaust emission control device 1 according to this embodiment will be described. The manufacturing method of the exhaust emission control device 1 according to the present embodiment includes (a) a molding step, (b) a sealing step, (c) a processing step, (d) a catalyst supporting step, and (e) a storing step. .

  First, in the forming step (a), a cylindrical honeycomb carrier made of cordierite is integrally formed by extrusion. As a result, a honeycomb carrier having a plurality of cells extending from the exhaust inflow side end surface to the outflow side end surface and serving as exhaust gas flow paths, and porous partition walls that define the cells is obtained.

  Next, in the plugging step (b), the honeycomb carrier formed in the forming step (a) is plugged by plugging the cell openings at a predetermined depth on both end surfaces in the central axis X direction. A portion 111 is formed. At this time, by alternately sealing the openings of adjacent cells, the cells in which the openings on the exhaust inflow side are sealed and the cells in which the openings on the outflow side are sealed are alternately checked. A wall flow structure arranged in a shape is formed. Thereby, the honeycomb carrier is filtered.

  In the (b) sealing step, the above-described conventionally known sealing agent is used. As a specific procedure for sealing, first, masking having openings alternately arranged in a checkered pattern corresponding to the opening positions of each cell of the honeycomb carrier is arranged on one end face of the honeycomb carrier. Next, by pouring a plugging agent from above, the plugging agent is alternately filled in the cell openings in a checkered pattern. At this time, the sealing depth of the sealing portion 111 is adjusted by adjusting the amount of the sealing agent and the sealing time. Thereafter, the same operation is performed on the other end face.

  Next, in the processing step (c), by grinding or cutting the outer peripheral portion P on both end faces of the sealed honeycomb carrier, the direction in which the cross-sectional area perpendicular to the central axis X direction becomes larger toward the outer peripheral side (outside thereof) The inclined portions 112a and 112b are formed in a direction in which the length of the peripheral edge in the direction of the central axis X decreases. As a processing method, grinding is preferably employed from the viewpoint that processing with higher accuracy is possible.

  In the processing step (c), the inclined portions 112a and 112b are formed so that the length dimension in the central axis X direction of the inclined portions 112a and 112b is larger than the sealing depth of the plugged portion 111. . Thereby, the inclined portions 112a and 112b constituting the outer peripheral portion P are sealed with the sealing region SR in which the inflow side opening portions and the outflow side opening portions of the adjacent cells are alternately sealed, and the respective cells. An opening region OR that is open without being formed is formed.

  Next, in the (d) catalyst supporting step, a three-way catalyst is supported on the honeycomb carrier 11 on which the inclined portions 112a and 112b are formed. As a specific procedure, first, one end face of the honeycomb carrier 11 in the direction of the central axis X is immersed in a slurry containing a three-way catalyst. Next, the slurry is sucked from the other end surface using a suction pump. Thereafter, the three-way catalyst is supported on the honeycomb carrier 11 by performing a heat treatment.

Next, in the (e) storing step, the inclined portions 112a and 112b are held by the inner wall of the case member 12 via the holding member 13, and the honeycomb carrier 11 on which the three-way catalyst is supported in the (d) catalyst supporting step is held. In this way, it is stored in the case member 12. At this time, the holding member 13 is arranged so that the position in the central axis X direction of the upstream end 131 of the holding member 13 overlaps the position in the central axis X direction of the sealing region SR of the inclined portion 112a.
As described above, the exhaust emission control device 1 according to the present embodiment is manufactured.

According to this embodiment, the following effects are produced.
In the present embodiment, the inclined portions 112a and 112b are formed in the outer peripheral portion P of the both end faces 110a and 110b in the central axis X direction of the honeycomb carrier 11 so that the cross-sectional area orthogonal to the central axis X direction increases toward the outer peripheral edge side. did. That is, the inclined portions 112a and 112b are formed in the direction in which the length in the central axis X direction on the outer peripheral edge of the honeycomb carrier 11 is reduced. The honeycomb carrier 11 was held in the case member 12 such that the outer peripheral portion P where the inclined portions 112 a and 112 b were formed was caught on the inner wall of the case member 12 via the holding member 13.
Thus, the honeycomb carrier 11 can be securely placed in the case member 12 by a simple structure in which the outer peripheral portion P of the honeycomb carrier 11 formed with the inclined portions 112a and 112b is hooked on the inner wall of the case member 12 via the holding member 13. Can be retained. In addition, since there is no need to use parts such as a mesh ring, a sufficient effective filter capacity and exhaust purification performance can be ensured.

In the present embodiment, the inclined portions 112a and 112b are disposed on the outer periphery of the sealing region SR in which the inflow side opening portions and the outflow side opening portions of adjacent cells are alternately sealed, and the sealing region SR. And an open region OR that is not sealed. And the holding member 13 was arrange | positioned so that the position of the central axis X direction of the upstream end 131 of the holding member 13 may overlap with the position of the sealing area SR in the inclined part 112a in the central axis X direction.
Here, when sealing the entire outer peripheral portion from the viewpoint of preventing leakage of particulate matter and ash, it is necessary to form the plug deeply across the entire end faces in the central axis direction of the honeycomb carrier. The effective capacity is reduced. On the other hand, according to the present embodiment, the opening region OR that is not sealed is formed in the outer peripheral portion P, and the opening region OR is reliably covered with the holding member 13, so that the effective capacity of the filter is sufficient. It is possible to reliably capture particulate matter and ash while ensuring the above. Further, since the upstream end 131 of the holding member 13 is configured not to protrude from the inflow side end face 110a of the honeycomb carrier 11, it is possible to suppress exhaust from directly hitting the upstream end of the holding member 13, and to suppress wind erosion of the holding member 13. .

  Further, according to the present embodiment, since the upstream end 131 of the holding member 13 is located in the plugged region SR of the inclined portion 112a, the unsealed opening region OR is formed in the outer peripheral portion P on the upstream side of the honeycomb carrier 11. The holding member 13 can reliably cover it. Therefore, particulate matter and ash do not flow into the outer peripheral portion P of the honeycomb carrier 11, and the outer peripheral portion P functions as an exhaust purification portion. Therefore, according to this embodiment, more excellent exhaust purification performance can be obtained.

[Second Embodiment]
FIG. 4 is an axial sectional view of the exhaust purification device 2 according to the second embodiment of the present invention. FIG. 5 is an enlarged view of the outer peripheral portion on the downstream side in FIG.
As shown in FIGS. 4 and 5, the exhaust purification apparatus 2 according to the second embodiment is different from the first embodiment except that the configuration of the outer peripheral portion P is reversed between the upstream side and the downstream side. Is the same configuration as in the first embodiment. That is, in the present embodiment, the holding member 23 is positioned so that the position of the downstream end 232 of the holding member 23 in the central axis X direction overlaps the position of the sealing region SR in the downstream inclined portion 212b in the central axis X direction. Has been placed.

The exhaust purification device 2 according to the present embodiment is manufactured by the same manufacturing method as the exhaust purification device 1 according to the first embodiment.
According to this embodiment, in addition to the effect of 1st Embodiment, the following effects are show | played.
In the present embodiment, the holding member 23 is disposed so that the position in the central axis X direction of the downstream end 232 of the holding member 23 overlaps the position in the central axis X direction of the sealing region SR in the downstream inclined portion 212b. .
According to the present embodiment, since the downstream end 232 of the holding member 23 is located in the plugged region SR of the downstream inclined portion 212b, an open region that is not plugged in the outer peripheral portion P on the downstream side of the honeycomb carrier 21. The OR can be reliably covered with the holding member 23. Therefore, when particulate matter or ash flows from the upstream outer peripheral portion P of the honeycomb carrier 21, the inflowing particulate matter or ash is captured without flowing out from the downstream outer peripheral portion P. That is, the outer peripheral portion P of the honeycomb carrier 21 functions as a particulate matter or ash capturing portion (pocket). Therefore, according to this embodiment, a more excellent filter function can be obtained, and particulate matter and ash can be captured more reliably.

[Third Embodiment]
FIG. 6 is an enlarged view of the upstream outer peripheral portion in the axial sectional view of the exhaust gas purification apparatus 3 according to the third embodiment of the present invention. FIG. 7 is a view of the honeycomb carrier 31 of the exhaust purification device 3 according to the third embodiment as viewed from the upstream side. FIG. 8 is a perspective view of the upstream outer peripheral portion of the honeycomb carrier 31 of the exhaust gas purification apparatus 3 according to the third embodiment.
The exhaust purification device 3 according to the third embodiment is the same as the first embodiment, except that the configuration on the upstream side of the outer peripheral portion P and the configuration on the upstream side of the case member 32 are different from those in the first embodiment. It is the composition.

  As shown in FIGS. 6 to 8, in the honeycomb carrier 31 of the present embodiment, a straight portion 313 extending in the central axis X direction is formed on the upstream side of the outer peripheral portion P. More specifically, a straight portion 313 extending in the central axis X direction is formed on the entire upstream side of the inclined portion 312a formed in the same manner as in the first embodiment. The straight portion 313 of the present embodiment constitutes the outer peripheral surface of the central portion C of the honeycomb carrier 31.

  The straight portion 313 is provided with a sealing region SR and an opening region OR. The holding member 33 is arranged so that the position in the central axis X direction of the upstream end 331 of the holding member 33 overlaps the position in the central axis X direction of the sealing region SR in the straight portion 313. That is, in the central axis X direction, the upstream end 331 of the holding member 33 is disposed within the range of the sealing region SR of the straight portion 313. As a result, the opening region OR of the straight portion 313 is reliably covered with the holding member 33, while the upstream end 331 of the holding member 33 protrudes from the inflow side end surface 310 a of the honeycomb carrier 31 due to the displacement of the holding member 33 during canning. This can be avoided more reliably.

  Moreover, in this embodiment, the case member 32 is comprised including the inclination part 321a, the straight part 322a, and the bending part 323a. The inclined portion 321 a and the straight portion 322 a are formed along the inclined portion 312 a and the straight portion 313 of the honeycomb carrier 31. Further, the bent portion 323 a is formed to be bent toward the honeycomb carrier 31 side outside the straight portion 313 of the honeycomb carrier 31. The bent portion 323a narrows the gap between the inflow side end surface 310a of the honeycomb carrier 31 and the case member 32. As a result, wind erosion of the holding member 33 is further suppressed.

The exhaust purification device 3 according to the present embodiment is different in that the outer peripheral portion P is ground or cut so as to form the straight portion 313 and the inclined portion in the (c) processing step of the manufacturing method according to the first embodiment. Except for this, the same manufacturing method as in the first embodiment is used.
According to this embodiment, in addition to the effect of 1st Embodiment, the following effects are show | played.
In the present embodiment, a straight portion 313 extending in the central axis X direction is formed at one end (upstream end) of the outer peripheral portion P in the central axis X direction, and the sealing region SR is disposed in the straight portion 313. Further, the holding member 33 is arranged so that the position of the upstream end 331 of the holding member 33 in the central axis X direction overlaps the position of the sealing region SR in the straight portion 313 in the central axis X direction.
Here, normally, the position of the holding member (the position of the upper end or the lower end of the holding member) is likely to vary during canning, and in order to absorb this variation, for example, the inclination length of the inclination formed on the outer periphery is increased. However, there is a limitation from the viewpoint of holding the honeycomb carrier in the case member.
On the other hand, according to the present embodiment, since the inclined portion 312a has the straight portion 313 in which the sealing region SR is disposed, even if the position of the holding member 33 varies during canning, the variation thereof is reduced. It can be absorbed by the straight portion 313. Therefore, according to this embodiment, the upstream end 331 of the holding member 33 is more reliably covered from the inflow side end surface 310a in the central axis X direction of the honeycomb carrier 31 while the opening region OR that is not sealed is more reliably covered with the holding member 33. Since it can avoid more reliably that it protrudes, the wind erosion of the holding member 33 can be suppressed more reliably.

It should be noted that the present invention is not limited to the above-described embodiment, and modifications and improvements within the scope that can achieve the object of the present invention are included in the present invention.
In the said embodiment, although the inclination part was formed in the outer peripheral part, it is not limited to this. A stepped portion may be formed instead of the inclined portion.
In the above embodiment, the exhaust purification catalyst (three-way catalyst) is supported on the entire honeycomb carrier, but the present invention is not limited to this. For example, the exhaust purification catalyst may be supported only on the central portion without being supported on the outer peripheral portion (inclined portion).
Moreover, in the said embodiment, although the inclination part was provided in both the upstream and downstream sides, it is not limited to this. For example, in the first embodiment and the third embodiment, the inclined portion may be provided only on the upstream side, and in the second embodiment, the inclined portion may be provided only on the downstream side.
Moreover, as a 3rd Embodiment, although the straight part was provided in the outer peripheral part of the upstream, it is not limited to this. A similar straight portion may be provided on the outer peripheral portion on the downstream side.

DESCRIPTION OF SYMBOLS 1, 2, 3 ... Exhaust gas purification apparatus 11, 21, 31 ... Honeycomb carrier 12, 22, 32 ... Case member 13, 23, 33 ... Holding member 110a, 210a, 310a ... Inflow side end surface 110b, 210b, 310b ... Outflow side End face 112a, 112b, 212a, 212b, 312a, 312b ... Inclined part 313 ... Straight part 131, 231, 331 ... Upstream end 132, 232, 332 ... Downstream end P ... Outer peripheral part C ... Central part SR ... Sealing area OR ... Opening area X ... central axis

Claims (4)

An exhaust purification device that is provided in an exhaust passage of an internal combustion engine and purifies exhaust of the internal combustion engine,
A columnar honeycomb carrier in which a plurality of cells extending from an exhaust inflow side end surface to an outflow side end surface and serving as exhaust flow paths are partitioned by porous partition walls;
An exhaust purification catalyst carried on the honeycomb carrier;
A cylindrical case member for storing the honeycomb carrier via a holding member,
The honeycomb carrier is formed on the outer peripheral side of both end faces in the central axis direction, and has an outer peripheral part having an inclined part or a step part formed so that a cross-sectional area perpendicular to the central axial direction increases toward the outer peripheral edge side. A central portion surrounded by the outer peripheral portion, and the outer peripheral portion is held in the case member by being hooked on the inner wall of the case member via the holding member,
In the central portion, the inflow side opening and the outflow side opening of the adjacent cell are alternately sealed, while the inclined portion or the stepped portion of the outer peripheral portion is outflowed from the inflow side opening of the adjacent cell. A side-opening alternately sealed area, and an opening area that is disposed on the outer periphery of the sealed area and is not sealed;
The holding member is disposed so that the position in the central axis direction of at least one of the upstream end and the downstream end thereof overlaps with the position in the central axis direction of the sealing region in the inclined portion or the stepped portion. Engine exhaust purification system.   2. The internal combustion engine according to claim 1, wherein the holding member is disposed such that a position in the central axis direction of an upstream end thereof overlaps a position in the central axis direction of the sealing region in the inclined portion or the stepped portion. Engine exhaust purification system.   The said holding member is arrange | positioned so that the position of the said central axis direction of the downstream end may overlap with the position of the said central axis direction of the said sealing area | region in the said inclination part or level | step difference part. Exhaust gas purification device for internal combustion engine. The outer peripheral portion is configured to include a straight portion that is formed at least at one end of both ends in the central axis direction and extends in the central axis direction,
The plugging area is disposed in the straight portion,
The said holding member is arrange | positioned so that the position of the said central axis direction of at least one of the upstream end and the downstream end may overlap with the position of the said central axis direction of the sealing area | region in the said straight part. The exhaust gas purification apparatus for an internal combustion engine according to any one of the above.

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