JP2003159531A - Metal catalyst carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a corner of the starting end of winding of a metal sheet from being damaged in a metal catalyst carrier. <P>SOLUTION: A cut-off starting point A is taken in a side end of a flat sheet 3 on an exhaust upstream side. The cut-off starting point A is set at a flat part 2 in the vicinity of a broken line between the flat part 2 to be a flat face by pinching the starting end of the flat sheet 3 by a winding axis and a winding area 5. A point B is taken in the winding starting end of the flat sheet 3, and a cutting line is made from the cut-off starting point to the point B. A point of intersection of an extension line along the winding starting end and an extension line of a line of a side end on the exhaust upstream side is a point C. The distance between the point A and C is a predetermined length (d), and the distance between the point B and C is a length 2d. The damage of the corner of the winding starting end of the flat sheet 3 and a wavy sheet 4 caused by heat of exhaust gas and vibration by pulsation flow can be prevented by making the corner of the winding starting end a cut-off shape. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a structure of a metal catalyst carrier installed in an exhaust system of a vehicle.

[0002]

2. Description of the Related Art In an exhaust system of a vehicle or the like, a metal catalyst carrier carrying a catalyst for oxidizing or reducing harmful components in the exhaust gas to purify it is installed. Many alternate windings have been proposed. In this metal catalyst carrier, a large number of cells are formed by a corrugated plate and a flat plate to ensure a contact area with exhaust gas. In order to further purify vehicle exhaust, E
There is a GR (exhaust gas recirculation) system. In this, part of the exhaust gas that has passed through the metal catalyst carrier is sent again to the engine intake side, mixed with a mixed gas of air and gasoline, and burned in the combustion chamber. This makes it possible to remove more harmful substances from the exhaust gas of the vehicle.

An example of this metal catalyst carrier is shown in FIG. The figure shows a large number of cells formed by a flat plate 3 and a corrugated plate 4 in a metal catalyst carrier 1 '. This is formed by stacking the flat plate 3 and the corrugated plate 4, sandwiching the tip of the flat plate 3 and the corrugated plate 4 by a winding shaft that is divided in two in the axial direction, and winding around the shaft. This makes it possible to obtain a columnar honeycomb body having innumerable cells in which the flat plates 3 and the corrugated plates 4 are alternately arranged. A brazing foil is wound around this columnar honeycomb body and inserted into an outer cylinder (not shown). Then, the honeycomb body is diffusion-bonded, and the outer cylinder and the outer periphery of the honeycomb body are brazed. In order to perform diffusion bonding of the honeycomb body, it is necessary to apply a predetermined bonding pressure to the structure, but it is difficult to apply the bonding pressure to the winding start end, and as a result, the bonding at this part tends not to be sufficient. is there.

[0004]

In such a metal catalyst carrier, the starting ends of the flat plate 3 and the corrugated plate 4 are difficult to be supported by others, so that there is no rigidity. Was concentrated. As a result, the upstream corner of the starting end becomes brittle, and vibrations due to the pulsating flow of exhaust gas may break the starting ends of the flat plate 3 and corrugated plate 4 at the beginning of winding. Further, when the broken pieces of the flat plate 3 or the corrugated plate 4 ride on the exhaust gas flow and are sent to the intake side of the engine by the EGR system, the broken pieces may enter the engine and cause damage to the inside of the engine.

Therefore, the present invention has been made in view of the above problems.
An object of the present invention is to provide a metal catalyst carrier that does not cause a breakage failure so that the winding start end portion of the metal catalyst carrier does not break into the inside of the engine.

[0006]

The invention according to claim 1 is
A flat plate made of metal and a corrugated plate made of metal are alternately superposed in a spiral shape, and in a metal catalyst carrier in which a cylindrical honeycomb body is formed, at least the corners of the flat plate and the corrugated plate at the start of winding start at the exhaust upstream side, It was supposed to be cut diagonally.

According to the second aspect of the present invention, the cutting start point for obliquely cutting is set to a flat portion near the bending point.

According to the third aspect of the invention, the cutting start point for obliquely cutting is set to the winding region.

According to a fourth aspect of the present invention, the corners of the starting ends of the flat plate and the corrugated plate are cut in a slanted shape by folding in instead of cutting.

According to a fifth aspect of the invention, the flat plate and the corrugated plate forming the columnar honeycomb body are diffusion-bonded.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, embodiments of the present invention will be described with reference to examples. FIG. 1 shows a perspective view of the first embodiment. In the metal catalyst carrier 1 of the first embodiment, the flat plate 3 and the corrugated plate 4 are superposed, the starting end portion thereof is sandwiched by a winding shaft (not shown) divided into two, and the flat plate 3 and the corrugated plate 4 are wound up. A large number of cells are formed inside. After winding a predetermined number of times, the end is fixed by spot welding or the like, and the winding shaft is pulled out to obtain a cylindrical honeycomb body in which flat plates 3 and corrugated plates 4 are alternately arranged. By being sandwiched by the winding shaft, the starting end portions of the flat plate 3 and the corrugated plate 4 become the flat portion 2, and the side end of the flat portion 2 is cut off obliquely. The broken line indicates the side edge of the conventional flat portion 2 which is not cut away. Although the corrugated plate shape of the corrugated plate 4 actually remains, the oblique cutting edge 6 of the corrugated plate 4 is shown by a straight line for easy understanding. A wax foil is wound around a cylindrical honeycomb body and inserted into an outer cylinder, and then the honeycomb body is diffusion-bonded, and the outer cylinder and the outer periphery of the honeycomb body are brazed.

FIG. 2 shows an enlarged view of the central portion of FIG. In the figure, the corrugated plate 4 is omitted in order to clearly show the shape of the winding start and
Only the flat plate 3 is shown. Cutting start points A and A ′ are set at the side ends of the flat plate 3 on the upstream side and the downstream side of the exhaust gas. The cutting start points A and A ′ are set in the flat portion 2 near the fold line between the flat portion 2 of the flat plate 3 and the winding area 5. Points B and B ′ are taken at the winding start end of the flat plate 3, and cuts are made from the cutting start points A and A ′ to the points B and B ′. The intersections of the extension lines along the winding start point and the extension lines of the exhaust upstream side and exhaust downstream side ends are respectively point C,
Let it be C '. The length between the cut start points A and C is d,
The length between the points B and C is 2d. Similarly, a length d is set between the cut start points A ′ and C ′, and a length 2 is set between the points B ′ and C ′.
d. As described above, the flat portion 2 of the flat plate 3 and the corrugated plate 4 has a shape in which both corners of the tip are cut off, the flat portion 2 is sandwiched by a winding shaft, and the flat plate 3 and the corrugated plate 4 are wound to form a cylindrical shape. A honeycomb body can be obtained.

The present embodiment is configured as described above, and the flat plate 3 and the corrugated plate 4 are formed by cutting off both corners of the winding start end so that the flat plate 3 and the corrugated plate are vibrated by the heat of the exhaust gas or the vibration due to the pulsating flow. It is possible to prevent breakage of both corners of the winding start point of No. 4 in advance. Also, by setting the cutting start points A and A'to the side ends of the flat portion 2, the area of the flat portion 2 which is sandwiched by the winding shaft at the time of manufacturing is secured, and the breakage of the corner at the start point of the winding is prevented. can do.

In the above embodiment, the flat plate 3 and the corrugated plate 4 are used.
In the above, the length between the cut start point A and the point C and between the cut start point A ′ and the point C ′ is d, and the length between the points B and C and the point B ′ and C ′ is 2d. Instead, a predetermined length is taken. In the flat plate 3 and the corrugated plate 4, a straight line is formed between the cut start point A and the point B and the cut start point A ′ to the point B ′, but the present invention is not limited to this, and as shown in FIG. It is also possible to cut in a concave arc shape from the cutting start point A to the point B and from the cutting start point A ′ to the point B ′. Further, as shown in FIG. 4, the flat portion 2 may be cut in a convex arc shape from the cutting start point A to the point B and from the cutting start point A ′ to the point B ′. As a further modified example, as shown in FIG.
And the length between the points B ′ and C ′ is longer than 2d, and the point E at the winding start start point of the flat plate 3 and the corrugated plate 4 is the apex.
The starting end may be sharp.

In the first embodiment described above, the corners at both ends of the flat plate 3 and the corrugated plate 4 at the start of winding are cut out so as to have the above-mentioned shape. May be. As a second embodiment, the cutting start points A and A ′ of the side edges of the flat plate 3 and the corrugated plate 4 are
The flat portion 2 is not limited to the flat portion 2 and may be provided at the side end of the winding region 5 as shown in FIG.

In each of the embodiments, the corner at the beginning of winding is cut off, but the corner at the beginning of winding may be bent to form a shape as if it were cut off. As a result, by folding the corner, the end of the starting end portion has a double structure, and the rigidity of the starting end portion can be increased. Moreover, the corner shapes of the flat plate 3 and the corrugated plate 4 may be different from each other as long as the corners of the starting ends of the winding start are cut off. Further, in the present embodiment, the honeycomb body is formed using the flat plate and the corrugated plate,
The honeycomb body may be formed of a large corrugated plate, a small corrugated plate or the like without being limited to this. Therefore, in the present invention, the flat plate includes a small corrugated plate having a smaller wave height than the corrugated plate (4).

[0017]

According to the first aspect of the present invention, since the corners of the winding start end of the flat plate and the corrugated plate are cut off, there is no corner of the winding start start that is particularly easily broken. It is possible to prevent breakage problems of corners caused by heat or pulsating flow. Further, even if the exhaust gas is returned to the engine intake side by the EGR system, the broken pieces of the metal catalyst carrier do not enter into the engine, so that the reliability of the EGR system can be improved.

According to the second aspect of the present invention, it is possible to prevent the breakage of the corner of the winding start starting end while ensuring the area of the flat portion of the winding start starting end which is sandwiched by the winding shaft during manufacturing.

According to the third aspect of the invention, since the cutting start point is set in the winding area, the corners formed on the side end faces of the flat plate and the corrugated plate by being cut obliquely are within the winding area. it can. As a result, it is possible to more reliably prevent breakage of the corner at the beginning of winding.

According to the fourth aspect of the present invention, by folding the corners of the starting ends of the flat plate and the corrugated plate, it is possible to obtain a shape in which the corners of the winding start starting end of the flat plate and the corrugated plate are cut off. Processing becomes unnecessary. Further, by folding the corners of the starting ends of the flat plate and the corrugated plate, the end of the starting end has a double structure, and the rigidity of the starting end can be increased.

According to the fifth aspect of the present invention, a problem occurs in the honeycomb body which is spirally overlapped and diffusion-bonded, that is, the pressure required for the diffusion bonding is less likely to be applied to the winding start point of the flat plate and the corrugated plate. By eliminating the corners of the starting end, it is possible to solve the problem that it is hard to be supported by others, so that there is no rigidity and a breakage defect at the starting end of the winding is likely to occur.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a perspective view of an enlarged view of a central portion of the present invention.

FIG. 3 is a perspective view of an enlarged view of a central portion of the present invention.

FIG. 4 is a perspective view of an enlarged view of a central portion of the present invention.

FIG. 5 is a perspective view of an enlarged view of the central portion of the present invention.

FIG. 6 is a perspective view of an enlarged view of the central portion of the present invention.

FIG. 7 is a perspective view showing a conventional metal catalyst carrier.

[Explanation of symbols]

1,1 'metal catalyst carrier 2 Flat part 3 flat plate 4 corrugated board 5 winding area 6 cut edges A, A'Crop start point B, B ', C, C', E point

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3G091 AB01 BA07 BA39 GA08 GA12                       GA13 GA16 GB01X                 4D048 BA39X BB02 BB04 BB13                       BB18                 4G069 AA01 AA08 BA17 CA02 CA03                       EA21 EA24 EA27 ED03 FA01                       FB66 FB69 FB71

Claims (5)

[Claims] 1. A metal catalyst carrier in which a flat plate made of metal and a corrugated plate made of metal are alternately wound in a spiral shape to form a cylindrical honeycomb body. A metal catalyst carrier, characterized in that a corner on the upstream side of exhaust gas is obliquely cut. 2. The metal catalyst carrier according to claim 1, wherein a cutting start point for obliquely cutting is set at a flat portion near the bending point. 3. The metal catalyst carrier according to claim 1, wherein a cutting start point for obliquely cutting is set in a winding region. 4. The corners of the starting ends of the flat plate and the corrugated plate are
The metal catalyst carrier according to claim 1, wherein the metal catalyst carrier has a shape that is cut obliquely by folding instead of cutting. 5. The metal catalyst carrier according to claim 1, 2, 3 or 4, wherein the flat plate and the corrugated plate forming the columnar honeycomb body are diffusion-bonded.