JP2005052743A - Metal carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a metal carrier which can be miniaturized by reducing the number of waves because the number of waves per unit volume is increased and the area of a raw material carrying a catalyst is increased by making the hight H of waves of a corrugated plate higher than the pich P. <P>SOLUTION: This metal carrier is characterized in that the height H of waves 1a of the corrugated plate 1 is made higher than the pitch P. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a metal carrier of a catalytic converter to be mounted on an exhaust system of an internal combustion engine or the like.

  As is well known, an exhaust system of an internal combustion engine or the like is equipped with a catalytic converter for purifying exhaust gas. As a catalyst carrier used in this type of catalytic converter, a metal such as an Fe-Cr-Al ferrite stainless steel foil material is used. A metal carrier made of a thin plate is widely used.

  In this type of metal carrier, strip-like corrugated plates and flat plates made of metal thin plates are alternately stacked, and these are wound in multiple layers to form a honeycomb-structured core having a circular cross section, and then a brazing foil on the outer periphery of the core It is manufactured by wrapping materials, press-fitting them into a metal outer cylinder and heating them in a vacuum state, thereby diffusion bonding the corrugated sheet and the flat plate and brazing the outer cylinder to the core. The

  In the conventional metal carrier of this type, as shown in FIG. 12, the height H of the wave 101a is smaller than the pitch P, and the angle θ formed by the flat plate 102 (not shown) and the wave 101a is small. Therefore, there is a problem that the compression force is not sufficiently transmitted and the diffusion bonding force becomes insufficient.

Further, as shown in FIG. 13, a phenomenon occurs in which the fillet 103 is generated due to the catalyst being accumulated by surface tension at the portion where the wave 101a and the flat plate 102 are in contact with each other. However, the fillet 103 does not function as a catalyst. For this reason, it is desired to reduce it.
JP 2000-61317 A

  The problems to be solved are that the compression force for diffusion-bonding the corrugated plate and the flat plate is not sufficiently transmitted to the center of the core, and the catalyst is caused by the fillet generated by the catalyst accumulating at the joint between the corrugated plate and the flat plate. This is a point where there is a lot of waste.

  The main feature of the metal carrier of the present invention is that the relationship between the wave height H of the corrugated plate and the pitch P satisfies H> P.

  In the metal carrier of the present invention, since the wave height H> pitch P of the corrugated plate increases, the number of waves per unit volume increases and the material area supporting the catalyst increases, so the number of turns is reduced. Miniaturization can be achieved. In addition, since the angle formed by the wave and the flat plate increases, the propagation rate of the compression force increases and the number of turns decreases, so that the compression force is easily transmitted toward the center of the core, so that the diffusion bonding force increases. Thereby, since the temperature at the time of heating in a vacuum state can be made low, productivity improves. Moreover, since the drawing process for increasing the propagation rate of the pressing force is not required, there is an advantage that the manufacturing is easy. Furthermore, since the number of fillets per unit area of the material is reduced, the amount of catalyst can be reduced, and the manufacturing cost can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view of a metal carrier manufacturing method according to an embodiment of the present invention, and FIG. 2 is a perspective view of the metal carrier according to the embodiment.

  3 is a partial cross-sectional view of the corrugated plate of the first embodiment, FIG. 4 is an explanatory view of the function and effect of the first embodiment, and FIG. 5 is a table showing the dimensions of the metal carrier of the first embodiment and the conventional metal carrier. It is.

  The basic structure of the metal carrier of the present embodiment is the same as that of the prior art, and as shown in FIG. 1, strip-like corrugated plates 1 and flat plates 2 made of metal thin plates are alternately stacked, and these are wound in multiple layers to obtain a cross section. After the core 3 having a honeycomb structure such as a circular shape is formed, a brazing foil material is wound around the outer periphery of the core 3, and these are press-fitted into a metal outer cylinder 4 as shown in FIG. By heating, the corrugated plate 1 and the flat plate 2 are diffusion bonded, and the outer tube 4 and the core 3 are brazed and bonded.

  As shown in FIG. 3, the height H (2.1 mm) of the wave 1a> pitch P (1.6 mm). The corrugated plate 1 is given a compression force f (see FIG. 4) via a flat plate 2 arranged on one side thereof, and this is adjacent to the corrugated plate (FIG. 4) via the flat plate 2 arranged on the other side. (Not shown) is propagated as a propagation force f ′. Since the propagation force f ′ is proportional to the product of sin θ and the compression force f, the propagation force f ′ increases as the angle θ increases.

  In addition, since H> P, the number of waves 1a per unit volume increases, and the area of the material carrying the catalyst (the sum of the area of the corrugated plate 1 and the area of the flat plate 2) increases, so the number of turns is reduced. The compression force can be easily propagated toward the center of the core 3. Therefore, the diffusion bonding force between the corrugated plate 1 and the flat plate 2 can be increased as compared with the conventional one. As a result, the temperature at the time of heating in a vacuum state can be lowered, and a drawing step for increasing the propagation force f 'is not necessary, so that there is an advantage that productivity is improved.

  In addition, since it becomes difficult to obtain the said effect if H / P is small, it is preferable that H / P is 2 or more. Moreover, since the number of fillets per unit area of the material is reduced by increasing the material area, the amount of catalyst can be reduced, and the manufacturing cost can be reduced.

  FIG. 5 shows the structure of this example and the conventional structure of a metal carrier (number of cells per square inch = 400) of the outer cylinder 4 having an outer diameter of 76.3 mm, a height of 40 mm, and a plate thickness of 1.5 mm. It is the table | surface which showed each part dimension with the thing. In addition, the plate | board thickness of the corrugated sheet 1 and the flat plate 2 is 50 micrometers. These plate thicknesses are preferably about 25 to 100 μm from the viewpoint of workability. From this table, it can be seen that the material according to the present invention has a larger material area and a smaller number of turns than the conventional one, and accordingly, the number of fillets per material area is decreased.

  FIG. 6 is a graph showing the relationship between H / P and material area of a metal carrier having 400 cells per square inch = 400. The material area increases as H / P increases, and the material area increases by about 20% at H / P = 2.4 compared to a standard metal carrier with H / P = 0.5.

  FIG. 7 is a graph showing the relationship between the H / P and the material area of a metal carrier having 200, 300, and 900 cells per square inch. As shown in this graph, even when the metal carrier has a number other than 400, the material area increases as H / P increases.

  FIG. 8 is a graph showing the relationship between H / P of a metal carrier having 400 cells per square inch = 400 and the number of fillets per unit area of the material. When H / P exceeds 1, the number of fillets per unit area is reduced by 10 to 20%, and wasteful catalysts can be reduced.

  FIG. 9 is a graph showing the relationship between the H / P and the number of fillets per unit area of a metal carrier having 200, 300, and 900 cells per square inch. As shown in this graph, the number of fillets per unit area decreases as H / P increases even for metal carriers other than the number of cells = 400.

  FIG. 10 is a partial cross-sectional view of the corrugated sheet 1 of the second embodiment. In this embodiment, the angle θ formed between the flat plate 2 and the both sides of the top of the wave 1a is approximately 90 °. By doing in this way, since the compression force f (refer FIG. 4) becomes difficult to escape, there exists an advantage that a diffusion joining force becomes larger.

  FIG. 11 is a partial sectional view of the corrugated sheet 1 of the third embodiment. In this embodiment, the wave 1a is formed in an Ω shape, and the angle θ formed with the flat plate 2 is greater than 90 °. By doing in this way, since the number of the waves 1a per unit volume can be increased more, a raw material area becomes larger and the number of fillets per unit area becomes smaller.

  The present invention is not limited to the above embodiments, and various modifications can be made to the above embodiments without departing from the gist of the present invention.

It is explanatory drawing of the manufacturing method of the metal carrier which is one Example of this invention. It is a perspective view of the metal carrier of an Example. It is a fragmentary sectional view of the corrugated sheet of 1st Example. It is explanatory drawing of the effect of 1st Example. It is a table | surface which shows each part dimension of the metal carrier of 1st Example, and the conventional metal carrier. It is a graph which shows the relationship between H / P of a metal support | carrier of the number of cells = 400, and a raw material area. It is a graph which shows the relationship between H / P of a metal support | carrier of cell number = 200,300,900, and raw material area. It is a graph which shows the relationship between H / P of a metal support | carrier of the number of cells = 400, and the number of fillets per material unit area. It is a graph which shows the relationship between H / P of the metal support | carrier of cell number = 200,300,900, and the number of fillets per unit area. It is a fragmentary sectional view of the corrugated sheet of 2nd Example. It is a fragmentary sectional view of the corrugated sheet of 3rd Example. It is a fragmentary sectional view of the corrugated sheet of the conventional metal carrier. It is a fragmentary sectional view of the conventional metal carrier.

Explanation of symbols

1 corrugated plate 1a wave 2 flat plate 3 core 4 outer cylinder

Claims (3)

  A corrugated plate (1) and a flat plate (2) made of a thin metal plate are alternately stacked, and a core (3) formed by winding them in multiple layers is press-fitted into a metal outer tube (4) to corrugate the plate. (1) and a flat plate (2) are diffusion-bonded and a metal carrier formed by brazing and joining the inner circumference of the outer cylinder (4) and the outer circumference of the core (3). A metal carrier characterized in that the relationship between the height H and the pitch P in (1a) satisfies H> P.   The metal carrier according to claim 1, wherein H / P is 2 or more. The metal carrier according to claim 1 or 2, wherein the corrugated plate (1) and the flat plate (2) have a thickness of 25 to 100 µm.

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