JPH10141053A - Manifold converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid defect due to poor welding, reduce the numbers of parts and processes and achieve a low cost by forming a catalyst case with a pipe material for a manifold converter in which the catalyst case is connected to an exhaust manifold to store a catalyst carrier therein. SOLUTION: A manifold converter 10 which is connected to an exhaust manifold has a catalyst carrier 16 stored in a catalyst case. The catalyst case formed by pressing a pipe material has a case mainbody 18 to hold the catalyst carrier 16, a tapered portion 20 formed in a tapered shape ranging to one end of the case mainbody 18, a case upstream side connection 22 connected to a collective tube for the exhaust manifold ranging to the tapered portion 20 and a case downstream side connection 24 widespread in a tapered shape ranging to the other end of the case mainbody 18. In this way, defect due to poor welding is avoided, the numbers of parts and processes are reduced and a low cost is achieved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a manifold converter, and more particularly to a manifold converter provided with a catalyst case connected to an exhaust manifold.

[0002]

2. Description of the Related Art In an engine of a vehicle or the like, a converter is provided in an exhaust system in order to exchange harmful exhaust gas from a combustion chamber into harmless exhaust gas by a catalytic substance under a predetermined gas composition and temperature condition. I have.

[0003] In some converters, a catalyst case accommodating a catalyst carrier is connected to an exhaust manifold and provided integrally therewith.

That is, as shown in FIGS. 13 and 14, a converter case 102 includes a half-shaped one-side case body 104-1 and a half-shaped other-side case body 104-2.
A catalyst carrier 110 is accommodated in the catalyst case 106 via an intervening member 108 made of a mat or the like. One side, other side case body 104-1, 104-2
Is made of a sheet metal material such as stainless steel, is pressed, and has one side end 104-1a of the one side case body 104-1.
Is superimposed on the outer surface of the other end 104-2a of the other case body 104-2, and the one side and the other side welded portions 112-1, 112-2 are overlapped.
Connected by

[0005] As shown in FIGS. 15 and 16, the converter 202 is provided with a half-shaped one-side case body 204-1 and a half-shaped other-side case body 204-2.
The catalyst carrier 210 is accommodated in the catalyst case 206 via an intervening member 208 made of a mat or the like. One side, the other side case body 204-1 and 204-2,
One side flange 204-1 made of sheet metal material such as stainless steel and pressed, and one side case body 204-1
a is the other side flange 204-a of the other side case body 204-2
, And connected by one-side and other-side welds 212-1 and 212-2.

In this case, as shown in FIG.
10 is stored in the catalyst case 206 by a load management method. This load management method is, for example, the other side case body 20
4-2, the lower half of the catalyst carrier 210 is stored, and the load when the one-side case body 204-1 is put on the upper half of the catalyst carrier 210 and pressed against the other-side case body 204-2 is measured. If the reaction force is insufficient, that is, the catalyst carrier 210
This is a method of determining that the product is defective if the holding is not tight, while determining that the product is good if the reaction force is sufficient.

[0007] There is a press-fit control method to this load control method. As shown in FIG. 18, this press-fit control method uses a catalyst carrier 3 via an intervening member 304 in a catalyst case 302 made of casting.
This is a method of measuring the press-fit reaction force at the time of press-fitting No. 06 and judging it as defective if this press-fit reaction force is insufficient, while judging it as good if the press-fit reaction force is sufficient. .

[0008] Such a manifold converter is disclosed, for example, in Japanese Utility Model Laid-Open No. 64-36614, Japanese Utility Model Laid-Open No. 5-38316, and Japanese Utility Model Laid-Open No. 5-77532. Japanese Unexamined Utility Model Publication No. 64-36614 discloses forming a catalyst coating layer on the inner surface of a manifold tube. 5-83
In the device disclosed in Japanese Patent Application Publication No. 16-216, in order to prevent deformation of the upstream diffuser and the cylindrical container due to thermal stress, a reinforcing flange bent inward is provided at the lower opening of the upstream diffuser. . Japanese Utility Model Laid-Open No. 5-77532 discloses a configuration in which a container serving as a catalyst case is connected to an exhaust manifold, and the upper open end of the container is connected to an exhaust outlet of a pipe so as to surround an exhaust outlet of the pipe. It is welded to the periphery of the hole.

[0009]

However, conventionally, FIG.
In the manifold converters shown in FIGS. 3 and 14 and FIGS. 15 and 16, since the one-side case body and the other-side case body are welded to form the catalyst case, defects due to poor welding are likely to occur. was there. In addition, in the case for a catalyst, there has been an inconvenience that the dimensional accuracy of the shape is deteriorated due to thermal distortion during welding. In addition, two parts,
In other words, since the one-side case body and the other-side case body are welded, the number of parts increases due to parts cost, welding cost, etc., compared to a single case, and the number of work processes increases, which is disadvantageous in cost. There was an inconvenience.

Further, in the converter shown in FIG. 18, since a catalyst case made of casting is used, the catalyst carrier can be easily press-fitted by machining the inner surface and the mouth. In the case of the case, it is difficult to process the mouth, etc., and is also inferior in strength to the casting, and the accuracy of the inner diameter is also inferior to the casting, so in the case of the method of pressing the catalyst carrier, There has been an inconvenience that it is difficult to hold the catalyst carrier.

Further, the catalyst case made of a sheet metal has a smaller heat capacity than that of a cast product, and the catalyst case is activated at an early stage necessary for complying with strict exhaust gas regulations. That is, the catalyst temperature is set to 15 to 20 seconds after the engine is started. Although it is a very effective means for raising the temperature to about 300 ° C. in a short time, it has been difficult to adopt it because of problems such as the performance of holding the catalyst carrier.

Furthermore, when a plurality of sheet metal parts are welded and joined together, the heat effect at the end of the weld bead cannot be forcibly ignored. Further, as shown in FIG. 19, when the former part 402 is located outside the latter part 404 and is welded at the welding part 406 by the welding torch, it becomes difficult for the welding torch to aim at the welding site and the welding operation becomes difficult. And, as shown in FIG.
Thus, there is a disadvantage that the space S is generated due to poor welding.

[0013]

SUMMARY OF THE INVENTION In order to eliminate the above-mentioned disadvantages, the present invention provides a manifold converter provided with a catalyst case accommodating a catalyst carrier connected to an exhaust manifold. It is characterized by being formed by a pipe material.

In a manifold converter provided with a catalyst case for accommodating a catalyst carrier connected to an exhaust manifold, the catalyst case is formed of a pipe material, and the quality of the catalyst carrier is determined by a press-fit reaction force. Characterized by being housed in the catalyst case by a press-fit control method.

Further, in a manifold converter provided with a catalyst case accommodating a catalyst carrier connected to an exhaust manifold, the catalyst case is formed of a pipe material, and the catalyst case is connected to the exhaust manifold. The former part is disposed so as to enter inside the latter part, and the latter part is connected to the outer surface of the former part by welding.

In a manifold converter provided with a catalyst case for accommodating a catalyst carrier connected to an exhaust manifold, the catalyst case is formed of a pipe material, and a throttle portion is provided at an inlet portion of the catalyst case. It is characterized by the following.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention eliminates the need for welding by forming a catalyst case with a tubular member.
Occurrence of defects due to poor welding can be avoided, the number of parts and the number of working steps can be reduced, which is advantageous in cost, and the dimensional accuracy of the shape of the catalyst case can be improved. In addition, since the catalyst carrier is press-fitted into the catalyst case by the press-fit control method, the surface pressure can be uniformly applied to improve the durability. Furthermore, by making the first-stage component enter the inside of the second-stage component, the durability can be improved, the welding operation can be facilitated, and welding defects can be eliminated.
Furthermore, by providing the throttle portion at the inlet portion of the catalyst case, the effective surface of the catalyst carrier can be utilized to the maximum extent, which can be advantageous for exhaust gas purification.

[0018]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; 1 to 5 show a first embodiment of the present invention. In FIG. 5, reference numeral 2 denotes an exhaust manifold attached to an engine (not shown). The exhaust manifold 2 includes a manifold flange 4 attached to the engine, four exhaust branch pipes 6, and a collecting pipe 8 for collecting the exhaust branch pipes 6.

The exhaust manifold 2 is provided with a manifold converter 10 connected thereto.

The manifold converter 10 is configured by housing a catalyst carrier 16 in a catalyst case 12 through an intervening member 14 made of a mat or the like.

As shown in FIG. 3, the catalyst case 12 is formed by pressing a pipe member 12 'which is a tubular member made of sheet metal, and includes a case body 18 for holding a catalyst carrier 16; A tapered portion 20 connected to one end of the portion 18 and formed in a tapered shape with a gradually decreasing diameter;
A case upstream connecting portion 22 connected to the collecting pipe 8 of the exhaust manifold 2 and connected to the tapered portion 20, and a case downstream connecting portion connected to the other end of the case body 18 and expanding in a tapered shape. 24.

A case upstream connecting portion 22 of the catalyst case 12 is provided in the collecting pipe 8 of the exhaust manifold 2 by being connected by welding or the like.

A connection flange 26 for attaching an exhaust pipe (not shown) is provided at the case downstream connection portion 24 of the catalyst case 12.

Next, the operation of the first embodiment will be described.

The exhaust gas of the exhaust manifold 2 from the collecting pipe 8 reaches the catalyst carrier 16 from the tapered portion 20 and is purified by the catalyst carrier 16.

In the first embodiment, since the catalyst case 12 is formed by pressing one pipe member 12 ', welding work is not required.
In addition to avoiding defects due to poor welding, the number of parts and work processes are reduced, which is advantageous in terms of cost.
The dimensional accuracy of the shape of the catalyst case 12 can be improved.

FIGS. 6 and 7 show a second embodiment of the present invention.

In the second embodiment, portions having the same functions as those in the first embodiment will be described with the same reference numerals.

The features of the second embodiment are as follows. That is, the catalyst carrier 16 is provided by being housed in the catalyst case 12 made of a pipe material via the intervening member 14 by a press-fit control method. This press-fit control method measures a press-fit reaction force when the catalyst carrier 16 is press-fitted into the catalyst case 12 via the intervening member 14, and determines that the product is defective if the press-fit reaction force is insufficient. On the other hand, if the press-in reaction force is sufficient, it is determined to be a non-defective product.

According to the press-fitting control method in the second embodiment, as shown in FIG. 7, an intervening member 14 is In addition, it is possible to uniformly apply a surface pressure to the catalyst case 12 to improve durability.

The catalyst case 12 is connected to a pipe member 12 ′.
Therefore, the catalyst case 12 is deformed following the surface pressure, whereby an even holding pressure can be obtained.

FIGS. 8 to 12 show a third embodiment of the present invention.

The features of the third embodiment are as follows. That is, the catalyst case 52 made of the pipe material of the manifold converter 10 is provided with the tapered body 54 at the preceding stage.
And the case body 56 at the subsequent stage are manufactured separately, and then connected by welding to be integrally formed.

The tapered body 54 has a tapered body upstream-side connecting portion 58 connected to the collecting pipe 8 of the exhaust manifold 2 at one end.
Is provided, and a tapered body downstream connection portion 60 to which the case body 56 is connected is provided on the other end side.

The case main body 56 has a main body upstream connection portion 62 connected to the tapered body downstream connection portion 60 at one end, and a main body downstream connection portion 64 at the other end.
Is provided. A connection flange 66 is provided at the main body downstream connection portion 64.

When the catalyst case 52 is connected to the exhaust manifold 2, the collecting pipe 8 of the exhaust manifold 2, which is the preceding part, is connected to the tapered body upstream connection portion 58 of the tapered body 54 which is the latter part. Is provided in the inside of the. On the outer surface of the collecting pipe 8, an end portion of the tapered body upstream connection portion 58 is welded by a welding torch.
1 is connected.

The tapered body downstream connection portion 60 of the tapered body 54, which is the preceding component, is provided inside the main body upstream connection portion 62 of the case body 56, which is the latter component. An end portion of the main body upstream connection portion 62 is connected to an outer surface of the taper body downstream connection portion 60 of the taper body 54 by a second welded portion 68-2 welded by a welding torch.

Further, the main body downstream side connection portion 64 of the case main body 56, which is a former part, is provided so as to enter into a hole 66a of a connection flange 66, which is a latter part. A connection flange 66 is connected to the outer surface of the case body 56 at a third welded portion 68-3 to be welded by a welding torch.

Further, the exhaust from each exhaust branch pipe 6 is once collected and mixed in the tapered body 54 in front of the catalyst carrier 16 which is the inlet portion of the catalyst case 12, and the catalyst carrier 16 is Aperture 7
0 is provided.

According to the structure of the third embodiment, as shown in FIG. 10, heat can be drawn up and down in the portion A affected by the heat of welding, but can be drawn only downward in the portion B. Therefore, the material deterioration due to the thermal influence is larger in the B portion.
However, the portion A, which is always less affected by heat (has a large margin of strength) with respect to the flow of exhaust gas, is always located inside the portion B, so that its durability is improved and the catalyst case 12 Can be improved in durability.

Also, unlike the case of FIG. 19, the welding torch can easily aim at the welded portion, simplify the welding operation, and prevent the occurrence of poor welding as shown in FIG. it can.

Further, as shown in FIG.
The exhaust portion discharged from each cylinder is gathered and mixed once, and the catalyst carrier 16
The exhaust gas is evenly applied to the entire front surface of the catalyst carrier 16, whereby the effective surface of the catalyst carrier 16 can be maximized, which is advantageous for exhaust gas purification.

Further, the exhaust sensor (not shown) is connected to the throttle unit 7.
If it is provided behind 0, the exhaust gas sensor detects the oxygen concentration after the exhaust gas from each cylinder is mixed, so that more accurate detection of oxygen is possible.

[0044]

As is apparent from the above detailed description, according to the present invention, since the catalyst case is made of a pipe material, welding is not required, defects due to poor welding are avoided, and the number of parts is reduced. And the number of working steps can be reduced, which is advantageous in terms of cost, and the dimensional accuracy of the shape of the catalyst case can be improved.

In addition, since the holding of the catalyst carrier is performed by the press-fitting control method, a uniform surface pressure is applied to parts such as the catalyst carrier, so that the holding performance of the catalyst carrier can be improved and the durability can be improved. Further, since the catalyst case deforms following the surface pressure, a uniform holding pressure is obtained.

Further, the front-stage components are inserted inside the rear-stage components, so that the components are affected by heat and the like.
In addition to improving the durability, the aim of the welding torch can be facilitated to simplify the welding work, and the welding failure can be avoided.

Further, since the throttle portion is provided at the entrance of the catalyst case, the exhaust is evenly applied to the entire front surface of the catalyst carrier, and the effective surface of the catalyst carrier is utilized to the maximum extent, which is advantageous for exhaust gas purification. obtain.

[Brief description of the drawings]

FIG. 1 is a perspective view of a manifold converter.

FIG. 2 is a cross-sectional view of a manifold converter.

FIG. 3 is a perspective view of a pipe member.

FIG. 4 is a perspective view of a catalyst case.

FIG. 5 is a perspective view in which a manifold converter is connected to an exhaust manifold.

FIG. 6 is a perspective view showing a press-fit state of a catalyst carrier by a pressure management method in a second embodiment.

FIG. 7 is a sectional view showing a state where a catalyst carrier is pressed into a catalyst case in a second embodiment.

FIG. 8 is a cross-sectional view of a third embodiment in which a manifold converter is connected to an exhaust manifold.

FIG. 9 is an enlarged cross-sectional view showing a state where a manifold converter is connected to an exhaust manifold by welding in the third embodiment.

FIG. 10 is a partially enlarged view of FIG. 9;

FIG. 11 is a sectional view showing a direction of a welding torch in a third embodiment.

FIG. 12 is a cross-sectional view showing a flow of exhaust gas by a throttle unit in a third embodiment.

FIG. 13 is a perspective view of a conventional manifold converter.

FIG. 14 is a cross-sectional view of the manifold converter of FIG.

FIG. 15 is a perspective view of a conventional manifold converter.

16 is a sectional view of the manifold converter of FIG.

FIG. 17 is a perspective view in which a catalyst carrier is provided in the manifold converter of FIG. 15 by a load management method.

FIG. 18 is a perspective view in which a catalyst carrier is provided in a cast catalyst case by a press-fit control method.

FIG. 19 is a cross-sectional view of a state in which a preceding component is positioned outside and connected to a subsequent component.

FIG. 20 is a partially enlarged cross-sectional view illustrating defective welding in FIG. 19;

[Explanation of symbols]

 2 Exhaust Manifold 10 Manifold Converter 12 Catalyst Case 12 ′ Pipe Material 14 Interposed Member 16 Catalyst Carrier

Claims (4)

[Claims] 1. A manifold converter provided with a catalyst case accommodating a catalyst carrier connected to an exhaust manifold, wherein the catalyst case is formed of a pipe material. 2. A manifold converter provided with a catalyst case accommodating a catalyst carrier connected to an exhaust manifold, wherein the catalyst case is formed of a pipe material,
A manifold converter, wherein the catalyst carrier is housed in the catalyst case by a press-fitting management method in which quality is determined in a press-fitting reaction state. 3. A manifold converter provided with a catalyst case for accommodating a catalyst carrier connected to an exhaust manifold, wherein the catalyst case is formed of a pipe material.
When the catalyst case is connected to the exhaust manifold, the former part is disposed so as to enter inside the latter part, and the latter part is provided by welding to the outer surface of the former part. A manifold converter. 4. A manifold converter provided with a catalyst case accommodating a catalyst carrier connected to an exhaust manifold, wherein the catalyst case is formed of a pipe material,
A manifold converter, wherein a throttle portion is provided at an inlet portion of the catalyst case.