JP2573290Y2 - Metal catalyst carrier - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal catalyst carrier used for purifying exhaust gas emitted from an automobile engine.

[0002]

2. Description of the Related Art As a catalyst carrier for purifying exhaust gas, a catalyst carrier formed of a honeycomb body using a metal foil instead of ceramic has recently been developed, and a part thereof has already been put into practical use. Generally, this type of metal catalyst carrier is formed by spirally winding a flat stainless steel foil having a thickness of about 50 μm and a corrugated stainless steel corrugated foil to form a cylindrical or elliptical honeycomb body. After being inserted into a stainless steel outer cylinder having a thickness of about 1 mm, a flat foil, a corrugated foil, and an outer cylinder are joined together by brazing or the like to produce a carrier.

When such a metal catalyst carrier is mounted on an exhaust gas system of an automobile engine, the carrier repeatedly undergoes a severe heat cycle of rapid heating and rapid cooling from the start to the stop of the engine. The metal honeycomb body repeatedly expands and contracts due to heat, and generates thermal stress. Therefore, when the braided foil and the flat foil or the honeycomb body and the outer cylinder are closely bonded to each other over the entire length, stress is concentrated at the bonded portion, and peeling is not preferable. In order to solve this problem, for example, as in Japanese Utility Model Application Laid-Open No. Sho 62-194436, a flat foil and a corrugated foil are joined in a partial cross section, and a honeycomb body and an outer cylinder are joined with a partial width in the axial direction. A non-joining surface is provided to alleviate the stress and prevent the two from separating.

[0004]

As described above, when the metal catalyst carrier is brazed to the corrugated foil and the flat foil and the honeycomb body and the outer cylinder by a part of the width in the axial direction, the exhaust gas is reduced to the metal catalyst carrier. When it enters from the non-bonding surface side, the unbonded portion of the core is undesirably lost due to the high temperature exhaust gas. Therefore, when the structure of the brazing joint of the metal catalyst carrier is asymmetric, it is necessary to identify the gas inlet side and the gas outlet side of the carrier and incorporate them into the automobile exhaust system. However, it was not possible to judge from the appearance of the metal catalyst carrier where the brazed joint was joined, and in some cases, the metal catalyst carrier was reversely assembled and the carrier was damaged, which was a problem.

The present invention solves such a problem, and provides a metal carrier which clarifies the front and rear of a metallic catalyst carrier and does not cause misidentification of front and rear when installed in an automobile exhaust system. The purpose is to do.

[0006]

That is, the present invention provides a honeycomb body formed by superimposing a flat foil and a corrugated foil made of a heat-resistant metal and spirally winding or laminating the same on an outer cylinder made of a heat-resistant metal. In the metal catalyst carrier to be stored and fixed, this honeycomb body is placed at least on the gas inlet side of the exhaust gas.
Placing a flat foil-corrugated joint, and a non-joined part on the gas exit side
A metal catalyst carrier characterized by having an asymmetric structure having: a length of one side of the outer cylinder in the axial direction is longer than an end face of the honeycomb body.

Next, the present invention will be described with reference to FIGS. In FIG. 1, 1 is an outer cylinder, 2 is a honeycomb body, and a metal catalyst carrier 3 is composed of the outer cylinder 1 and a honeycomb body 2. As shown in FIG. 3, the honeycomb body 2 is formed by laminating a flat foil 4 made of a heat-resistant metal and a corrugated foil 5 and winding them in a spiral shape, or by laminating the flat foil 4 and the corrugated foil 5 as shown in FIG. It is formed. Such a honeycomb body 2 has a flat foil 4
In many cases, a material in which a bonding portion 6 is partially formed from the corrugated foil 5 or a material in which the honeycomb body 2 and the outer cylinder 1 are bonded to each other with a partial width in the axial direction is used.

[0008] Such a metal catalyst carrier 3 is incorporated in an automobile exhaust system and purifies exhaust gas. However, it is necessary to arrange the metal catalyst carrier 3 such that the joint 6 comes to the exhaust gas inlet side. However, when assembling into an automobile exhaust system, it is not possible to recognize the position of the joint 6 such as a brazing joint,
The present invention is made to be recognizable from the appearance. That is, as shown in FIG. 1, when manufacturing the metal catalyst carrier, the length of the outer cylinder 1 on the gas inlet side of the honeycomb body 2 is adjusted so that the joint 6 of the metal catalyst carrier 3 can be recognized. A space 7 longer than the end face is formed. Thus, the side where the outer cylinder 1 is longer than the end face of the honeycomb body 2 and the space 7 exists can be recognized as the joint side of the metal catalyst carrier 3.

As described above, the length of the outer cylinder 1 on the gas inlet side, that is, the joint side may be increased, or the length of the outer cylinder 1 on the gas outlet side may be increased as shown in FIG. It may be longer than the end face of the body 2. That is, it is only necessary to decide beforehand when the honeycomb body is inserted into the outer cylinder.

When the outer cylinder is made longer than the end face of the honeycomb body, it is preferable that the outer cylinder is about 3 mm to 5 mm. This is sufficient because it is sufficient to confirm whether the outer cylinder is longer than the end face of the honeycomb body.

[0011]

According to the present invention, according to the metal catalyst carrier, exhaust gas can be reliably passed from the joint side when the metal catalyst carrier is incorporated into an exhaust system of an automobile. This makes it possible to prevent the carrier from being damaged, and the effect is extremely large.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a metal catalyst carrier of the present invention.

FIG. 2 is an explanatory view of another metal catalyst carrier of the present invention.

FIG. 3 is an explanatory view of a honeycomb body in which a flat foil and a corrugated foil are wound.

FIG. 4 is an explanatory diagram of a honeycomb body in which a flat foil and a corrugated foil are laminated.

[Explanation of symbols]

 1: outer cylinder 2: honeycomb body 3: metal catalyst carrier 4: flat foil 5: corrugated foil 6: joint 7: space

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B01J 35/04 F01N 3/28 B01D 53/36

Claims (1)

(57) [Scope of request for utility model registration] 1. A metal catalyst carrier in which a flat body and a corrugated sheet made of a heat-resistant metal are superposed and spirally wound or laminated to form a honeycomb body which is housed and fixed in an outer cylinder made of a heat-resistant metal. In this honeycomb body, at least
Placing a flat foil-corrugated joint on the gas inlet side of the exhaust gas, and
With an asymmetric structure having a non-joining part on the gas exit side,
A metal catalyst carrier, characterized in that one side of the axial length of the outer cylinder is longer than the end face of the honeycomb body.