JP2002070546A - Exhaust system pipe mounted with catalyst pipe and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exhaust system pipe mounted with a long catalyst pipe capable of installing on the inside of a bent part of an exhaust pipe or a bent part of a joint pipe, and provide its manufacturing method. SOLUTION: A metal net body 15A is formed in a cylinder, either one of works installing a holding ring 17 at one end part of the cylindrical metal net body and carrying a catalyst S in the net body is executed at first, the cylindrical metal net body is inserted from the tip side having no holding ring into the exhaust pipe 1 bent in the specified shape or into joint pipes 5, 7 bent in the specified shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust pipe equipped with a catalyst pipe for reducing pollution and protecting the environment due to exhaust gas from automobiles and motorcycles, and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, an exhaust pipe connected to an exhaust port of an engine and a joint pipe with a silencer connected to the exhaust pipe have been used to reduce pollution and protect the environment due to exhaust gas from automobiles and motorcycles. , One or more catalyst pipes carrying a catalyst are inserted and arranged.

FIG. 10 shows a specific structure of the conventional catalyst pipe. This drawing shows a silencer 10 attached to an engine of a motorcycle or the like, in which four curved exhaust pipes 1 connected to an exhaust port of the engine, and a converging pipe section 3 which is subsequently integrated into one.
And joint pipes 5 and 7 which are bifurcated and bent, and silencers 9 and 9 connected thereto. The straight extension 1 of the exhaust pipe 1 in the silencer 10
A and a plurality of short catalyst pipes 11 are provided in A and in the straight extensions 5A and 7A of the joint pipes 5 and 7. This is because the effect of purifying exhaust gas by the catalyst pipe is more effective if the catalyst pipe is arranged as close to the engine as possible, but is installed as described above because only a straight pipe can be installed. Because. The catalyst pipe 11 supports the catalyst 13 on a short pipe 11B having a punched hole 11A and has a support ring 15 welded to the exhaust side. The catalyst pipe 11 is inserted into the straight extension portion 1A or the straight extension portions 5A and 7A, and is welded to the inner wall by the support ring 15.

[0004] The catalyst pipe has a short pipe 11B having a punched hole 11A and carries a catalyst made of, for example, platinum, palladium, and rhodium. The catalyst pipe has a high temperature range of 400 ° C or more near the exhaust pipe just discharged from the engine. In the above, an effect of reducing the nitrogen oxide NOX by a chemical reaction is exhibited. However, in the curved portion near the exhaust pipe and in the curved portion of the joint pipe, the catalyst pipe cannot be installed in the entire length because the curved portion is curved. For this reason, in order to achieve predetermined pollution reduction and environmental protection, it is necessary to divide and install many short catalyst pipes in the straight section apart from the exhaust pipe where the exhaust temperature has necessarily become low. In addition, there is a problem that the exhaust gas purification efficiency is poor and the cost is high.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the structural problems of the above-mentioned conventional catalyst pipes, and has a long catalyst pipe which can be installed in a curved portion of an exhaust pipe or a curved portion of a joint pipe. It is an object of the present invention to provide an exhaust pipe equipped with a pipe and a method for manufacturing the same.

[0006]

Means for Solving the Problems The present invention has been made to achieve the above object, and a method for manufacturing an exhaust pipe equipped with a catalyst pipe according to claim 1 comprises forming a metal mesh body into a cylindrical shape, Either a holding ring is attached to one end of the cylindrical wire netting, or a catalyst is carried on the wire netting, either before or after, and the cylindrical wire netting is moved to the tip without the holding ring. It is characterized in that it is inserted and arranged in an exhaust pipe bent into a predetermined shape from the side or a joint pipe bent in a predetermined shape.

[0007] In the exhaust pipe equipped with the catalyst pipe according to the second aspect, the catalyst is supported on a cylindrical wire mesh, and a holding ring is provided at one end of the wire mesh. Characterized in that it is inserted and disposed in an exhaust pipe bent into a predetermined shape from a tip side without the joint or a joint pipe bent into a predetermined shape.

According to a third aspect of the present invention, there is provided a method for manufacturing an exhaust pipe equipped with a catalyst pipe, wherein a plurality of long pipes elongated in a direction perpendicular to the axial direction or an inner pipe of a cylindrical metal mesh body. A step of attaching retaining rings to both ends of a drilled straight tubular inner pipe, or a straight tubular inner pipe formed of an expanded material formed by drilling a number of diamond-shaped or turtle-shaped holes,
Alternatively, the step of supporting the catalyst on the inner pipe is performed before or after, and subsequently, the straight inner pipe is inserted into the outer outer pipe, and the inner pipe has a double pipe structure. Joining, closing one end of the double pipe with a lid, filling the inside of the pipe with a liquid that can be frozen, and cooling the entire double pipe to freeze the liquid in the double pipe And a step of bending the double pipe to a desired angle by a bending means, and a step of draining liquid from inside the double pipe.

According to a fourth aspect of the present invention, there is provided a method of manufacturing an exhaust system pipe having a catalyst pipe mounted thereon, the method comprising the steps of: During or before the process of joining to the structure
A step of interposing a silencer in the annular gap between the inner and outer pipes is added.

According to a fifth aspect of the present invention, there is provided a method for manufacturing an exhaust pipe having a catalyst pipe mounted thereon, wherein the inner pipe and the outer pipe are joined to a double pipe structure. In the process, the outer pipe is
An outer cylinder, a straight tubular inner cylinder in which many long holes are staggered in a direction perpendicular to the axial direction installed in the inner cylinder, or a number of rhombic or turtle-shaped holes are drilled. A triple pipe comprising a straight tubular inner tubular body formed of an expanded material, wherein the inner tubular body is inserted with the silencing material interposed in the outer tubular body, and the inner pipe is inserted on the inner diameter side of the inner tubular body. It is characterized by being joined to a structure.

According to a sixth aspect of the present invention, in the exhaust pipe equipped with the catalyst pipe, the inner pipe inserted inside the outer pipe is an inner pipe of a metal mesh body formed in a cylindrical shape, or a direction orthogonal to the axis direction. A straight tubular inner pipe in which a number of long holes are staggered, or a straight tubular inner pipe formed of an expanded material in which a number of diamond-shaped or turtle-shaped holes are drilled. , And held inside the outer pipe via holding rings attached to both ends of the inner pipe, and the inner and outer pipes are bent at appropriate angles.

[0012] In the exhaust pipe equipped with the catalyst pipe according to claim 7, the exhaust pipe provided with the catalyst pipe according to claim 6 has a sound deadening material interposed in an annular gap between the outer pipe and the inner pipe. It is characterized by the following.

[0013] The exhaust pipe provided with the catalyst pipe according to claim 8 is the exhaust pipe provided with the catalyst pipe according to claim 6, wherein the outer pipe comprises an outer cylinder and a cylindrical member provided inside the outer cylinder. An inner cylindrical body of a wire mesh body formed in the above, or a straight tubular inner cylindrical body in which a number of long holes long in a direction perpendicular to the axial direction are formed in a staggered manner, or a number of rhombic or turtle-shaped holes are formed. And a straight tubular inner cylinder formed of an expanded material, comprising a muffler in an annular gap between the outer cylinder and the inner cylinder, and an inner pipe on the inner diameter side of the inner cylinder. It is characterized by having a triple pipe structure inserted.

[0014]

According to the first aspect, first, the wire mesh body is formed in a cylindrical shape, and either a holding ring is provided at one end of the cylindrical wire mesh body, or a catalyst is supported on the wire mesh body. Is executed before and after. Then, the cylindrical wire netting is inserted into an exhaust pipe bent into a predetermined shape or a joint pipe bent into a predetermined shape from the distal end side without the holding ring while being deformed along the curved inner surface. Deploy. This makes it possible to easily attach a long catalyst pipe in the curved portion of the exhaust pipe or in the curved portion of the joint pipe.

According to a second aspect of the present invention, the catalyst is supported on the cylindrical wire netting, and a holding ring is attached to one end of the wire netting. An exhaust pipe bent into a predetermined shape, or a joint pipe bent into a predetermined shape is disposed, whereby an exhaust pipe bent long and formed close to the engine or a joint pipe bent into a predetermined shape is provided. The exhaust pipe can be an exhaust pipe in which one long catalyst pipe is mounted, and the purification efficiency of exhaust gas can be improved.

According to the third aspect, first, an inner pipe of a metal mesh body formed in a cylindrical shape, a straight inner pipe in which a number of long holes elongated in a direction perpendicular to the axial direction are staggered, or A straight inner pipe made of an expanded material having a large number of diamond-shaped or turtle-shaped holes is prepared. next,
A holding ring is attached to both ends of the inner pipe, or
The process is carried out before or after either carrying the catalyst on the inner pipe. Subsequently, while inserting the straight tubular inner pipe into the straight tubular outer pipe, joining it to the double pipe structure of the inner and outer pipes, closing one end of the double pipe with a lid and freezing inside the pipe Fill the liquid, cool the entire double pipe and freeze the liquid in the double pipe,
The double pipe can be freely bent to a desired angle by a bending means. Finally, an exhaust system pipe equipped with a catalyst pipe is manufactured by draining liquid from the inside of the double pipe.

The inner pipe may be an inner pipe of a wire mesh body, a straight tubular inner pipe in which a number of long holes extending in a direction perpendicular to the axial direction are formed in a staggered manner, or a number of rhombic or turtle-shaped holes. It consists of a straight tubular inner pipe formed of expanded material that is pierced, and the outer diameter side of the bending is easily expanded and deformed in the axial direction with respect to the bending force in the direction perpendicular to the axial direction,
The inner diameter side of the bending is easily reduced in the axial direction. Therefore, the portion where the wire mesh or the long hole or the rhombic or turtle-shaped hole is formed freely expands and contracts, and can be easily bent to a desired angle without causing cracks and wrinkles on the wall surface of the inner pipe. Further, the catalyst carried on this surface does not peel off during the bending action due to the bending action of the inner pipe.

According to the method for manufacturing an exhaust pipe equipped with the catalyst pipe, one long catalyst pipe is inserted into the exhaust pipe or the joint pipe connected to the exhaust port of the engine via the holding rings at both ends thereof. A mounted exhaust pipe can be formed. Thus, an exhaust pipe capable of efficiently purifying waste gas within a long curved path in an exhaust pipe or a joint pipe having a high exhaust temperature can be manufactured at low cost.

According to a fourth aspect of the present invention, in the method for manufacturing an exhaust system pipe provided with the catalyst pipe according to the third aspect, at the time of or before the step of joining to the double pipe structure of the outer pipe and the inner pipe, A step of interposing a silencing material in the annular gap of the pipe is added.

Thus, when the high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, the exhaust gas effectively expands from a number of long holes to the silencer to reduce the internal pressure,
Exhibits an excellent noise reduction effect and can efficiently purify exhaust gas.

According to a fifth aspect of the present invention, in the method for manufacturing an exhaust pipe equipped with the catalyst pipe according to the third aspect, in the step of joining the inner pipe and the outer pipe to a double pipe structure, the outer pipe is an outer cylindrical body. And a straight tubular inner cylinder body in which a number of long holes extending in a direction perpendicular to the axis direction are provided in a zigzag manner, or an expanded material in which a number of rhombic or turtle-shaped holes are provided. A straight pipe inner cylinder formed by the above, while inserting the inner cylinder with a silencing material interposed in the outer cylinder, and a triple pipe structure in which the inner pipe is inserted on the inner diameter side of this inner cylinder Join.

Thus, when the high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, it effectively expands and lowers the internal pressure, thereby exhibiting an excellent noise reduction effect, and at the same time improving the exhaust gas efficiency. Can be purified well.

According to the sixth aspect of the present invention, the inner pipe inserted into the outer pipe is formed of a cylindrical metal mesh body inner pipe or a large number of long holes staggered in a direction perpendicular to the axial direction. A perforated straight tubular inner pipe or a straight tubular inner pipe formed of an expanded material formed by perforating a large number of diamond-shaped or turtle-shaped holes is employed. The inner pipe carries a catalyst and is held inside the outer pipe via holding rings provided at both ends of the inner pipe. Further, the inner and outer pipes are bent at appropriate angles.

Thus, an exhaust pipe having one long catalyst pipe mounted in a long bent exhaust pipe connected to an exhaust port of an engine or a joint pipe bent in a predetermined shape through holding rings at both ends thereof. It becomes a system pipe, and the purification action of the waste gas is efficiently performed in a long path in the exhaust pipe having a high exhaust temperature, so that the purification efficiency of the exhaust gas can be improved.

According to the seventh aspect, in the exhaust pipe equipped with the catalyst pipe according to the sixth aspect, a sound deadening material is interposed in the annular gap between the inner and outer pipes having the double pipe structure of the outer pipe and the inner pipe. .

As a result, when high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, the exhaust gas is effectively expanded from a large number of long holes and the like to the silencer, thereby reducing the internal pressure. In addition to exhibiting a noise reduction effect, exhaust gas can be efficiently purified.

According to an eighth aspect of the present invention, in the exhaust pipe equipped with the catalyst pipe according to the sixth aspect, regarding the double pipe structure of the inner and outer pipes, the outer pipe has an outer cylinder and a shaft installed inside the outer cylinder. Straight inner tubular body with a number of long holes staggered in the direction perpendicular to the direction, or a straight inner tubular body formed of expanded material with a large number of diamond-shaped or turtle-shaped holes It consists of: Then, a triple pipe structure is obtained in which the inner cylinder is inserted with the silencing material interposed in the outer cylinder, and the inner pipe is inserted on the inner diameter side of the inner cylinder.

Thus, when the high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, it effectively expands and lowers the internal pressure, thereby exhibiting an excellent noise reduction effect and reducing the exhaust gas efficiency. Can be purified well.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an external view of an entire silencer attached to an engine of a motorcycle or the like, and FIG. 2 is a process diagram showing a method of manufacturing an exhaust pipe equipped with a catalyst pipe according to the present invention.

FIG. 1 shows a muffler 50 attached to an engine of a motorcycle or the like, which is connected to an exhaust port of the engine. Four curved exhaust pipes 1, followed by a converged converging pipe section 3, one of which is bifurcated and bent and joint pipes 5 and 7, and two of which are connected thereto And a silencer 9. In the present invention, the exhaust pipe 1 and the joint pipes 5, 7 are referred to as an exhaust pipe. In the silencer 50, one long catalyst pipe 15B is provided within the bent entire length of the joint pipes 5 and 7 to constitute an exhaust pipe 100 equipped with the catalyst pipe of the present invention. Further, the catalyst S is carried on the punching metal 20, the holding rings 17 are attached to both ends, and the holding rings 17 are inserted into the exhaust pipe 1 to constitute an exhaust system pipe 200 equipped with the catalyst pipe of the present invention. Of course, it is effective to dispose the exhaust gas at the location of the exhaust pipe 1 or the joint pipes 5, 7 close to the engine.

Next, a method of manufacturing the exhaust pipe 100 equipped with the above-described catalyst pipe according to the first embodiment will be described with reference to FIG. First, a stainless steel material (SUS
(A) Wire mesh sheet which prepares the wire mesh 15 formed in 436). Then, the wire mesh 15 is formed into a cylindrical shape to form a wire mesh body 15A. Subsequently, a holding ring 17 is attached to one end of the cylindrical wire netting 15A (“(c) holding ring”). Next, in order to carry the catalyst S on the wire netting 15A, the wire netting 15A is immersed in the catalyst bath 19, and either “(d) baking” or “(e) baking” with the heater H is performed. And run.
Furthermore, the cylindrical wire netting 15A is inserted and arranged in the joint pipes 5 and 7 which are bent into a predetermined shape from the front end side where the holding ring 17 is not provided (“(f) Inserting and assembling”). Of course, it may be inserted and arranged in the exhaust pipe 1. Thereby, the long catalyst pipe 15B can be easily attached to the inside of the curved portion of the exhaust pipe 1 and the curved portions of the joint pipes 5 and 7.

As described above, according to the method for manufacturing the exhaust pipe 100 equipped with the catalyst pipe, one bendable pipe is formed in the exhaust pipe 1 and the joint pipes 5 and 7 which are previously formed into a predetermined shape. The exhaust pipe 100 equipped with the long catalyst pipe 15B can be easily manufactured. Thus, an exhaust pipe capable of improving the purification efficiency of exhaust gas can be manufactured at low cost.

The exhaust pipe 10 with the catalyst pipe mounted thereon
Reference numeral 0 indicates that the catalyst S is supported on the cylindrical wire mesh body 15A, and a holding ring 17 is attached to one end of the wire mesh body. The wire mesh body is bent into a predetermined shape from the front end side without the holding ring. The exhaust pipe 1 or the joint pipes 5 and 7 bent into a predetermined shape are arranged.

Exhaust pipe 1 formed long and bent
The exhaust system pipe 100 in which one long bendable catalyst pipe is mounted in the joint pipes 5 and 7 bent and formed in a predetermined shape has excellent exhaust gas purification efficiency.

Next, as shown in FIG. 1, the catalyst S is carried on the inner pipe made of the punching metal 20,
A second embodiment of an exhaust system pipe 200 in which holding rings 17 are attached to both ends and inserted and arranged in the exhaust pipe 1 and the like will be described.

A method of manufacturing the exhaust pipe 200 according to the second embodiment will be described with reference to FIG. 3 and FIGS. First, a straight tubular inner pipe 20A in which a number of long holes are formed in a zigzag pattern in a direction perpendicular to the axial center direction に よ り by punching metal 20.
"Pipe forming step A". Subsequently, a "holding ring attaching step B" in which holding rings 17 are attached to both ends of the cylindrical inner pipe 20A. Further, in order to carry the catalyst S on the inner pipe 20A, the inner pipe 20A is
A “dip baking process C” in which water is blown into the inside 9 and baking is performed, and baking is performed by the heater H. The “retaining ring attaching step B” and the “drilling and baking step C” are executed before or after any one of them. The inner pipe 20A that has been subjected to the “bombing and baking process C” becomes a catalyst pipe. Further, the cylindrical inner pipe 20A is straightened into an exhaust pipe 1,
Or, while being inserted into the outer pipe 10 composed of the joint pipes 5 and 7, the holding rings 1 at both ends of the inner pipe 20A are provided.
7. "Joining step D" where the outer pipe 10 is joined by welding or the like at an appropriate position (for example, an end) and integrated to form a double pipe 30A.

Next, one end 30 of the double pipe 30A
X is closed with the lid 35, and the inside of the pipe is filled with a liquid W such as water that can be frozen (filling step E). As the freezeable liquid W, water, ice, liquid paraffin, or the like can be used. next,
The entirety of the double pipe 30A is cooled by the refrigerator L to freeze the liquid W in the double pipe (freezing step F). Thereafter, the double pipe is bent to a desired angle by a bending means (pipe bender, press machine, etc.) M (bending step G). Finally, the entire pipe is heated and thawed by the dryer H1 or spontaneously thawed to remove liquid from the inside of the double pipe 30A (water draining step H).

In the method of manufacturing the exhaust pipe 200 equipped with the catalyst pipe 20A, as shown in FIG. 4, the double pipe 30A is configured such that the inner pipe 20A which is a catalyst pipe is A large number of long holes 20 </ b> B are formed in a zigzag pattern in a direction perpendicular to the direction. Therefore, when the double pipe 30A is frozen and then bent at a desired angle by a bending means (pipe bender, press machine, etc.) M in the bending step G, the inner pipe 20A becomes, as shown in FIG. The outer diameter side of the bending easily expands and deforms in the axial direction О and the inner diameter side of the bending easily reduces and deforms in the axial direction に 対 し て with respect to the bending force Fo in the direction in which the hole 20B is orthogonal to the axial direction О. You. Therefore, since the cracks and wrinkles do not occur on the wall surface of the inner pipe 20A, the catalyst S baked on this surface is easily bent to a desired angle Q without peeling.

According to the method of manufacturing the exhaust pipe 200 equipped with the catalyst pipe serving as the inner pipe 20A, the exhaust pipe 1 is formed into a long bent exhaust pipe 1 connected to the exhaust port of the engine, or into a predetermined shape. In the joint pipes 5, 7, an exhaust pipe 200 in which one long catalyst pipe 20A is installed via holding rings 17 at both ends thereof is formed.

As a result, the long catalyst pipe 20A is installed in the exhaust pipe 1 where the temperature of the exhaust gas is high and in the curved long path in the joint pipes 5 and 7.
The purifying action of the waste gas can be efficiently performed, the purifying efficiency of the exhaust gas can be improved, and the exhaust system pipe 200 equipped with the catalyst pipe can be manufactured at low cost.

Next, with reference to FIGS. 3 and 6, a description will be given of a method of manufacturing the exhaust pipe 300 equipped with the catalyst pipe of the third embodiment using the expanded metal 23 as the inner pipe.
The manufacturing method is almost the same as in the second embodiment.
First, the expanded metal 23 serving as the inner pipe 23A
Has a number of diamond-shaped or tortoise-shaped holes 23E in its peripheral surface 23D.
Formed of an expanded material. This is a mesh-shaped member in which a large number of slits are drilled in a steel plate in a zigzag pattern and stretched by a stretcher to form a large number of diamond-shaped or tortoise-shaped holes 23E. In the present invention, this is a cylindrical member. "Pipe forming step A" for forming the straight inner pipe 23A. Subsequently, a "holding ring attaching step B" in which holding rings 17 are attached to both ends of the cylindrical inner pipe 23A. Further, in order to carry the catalyst S on the inner pipe 23A, the inner pipe 23A is immersed in the catalyst bath 19 to perform dozing and baking by the heater H. The “retaining ring attaching step B” and the “drilling and baking step C” are executed before or after any one of them. The inner pipe 23A after the above-mentioned "blow-on baking process C" becomes the catalyst pipe 23A. Furthermore, the cylindrical inner pipe 2
3A is inserted into the straightened exhaust pipe 1 or the outer pipe 10 composed of the joint pipes 5 and 7, and the holding rings 17 at both ends of the inner pipe 23A are welded to appropriate places (for example, ends) of the outer pipe 10. "Joining process D" which is joined and integrated into a double pipe 30C.

Next, one end 30 of the double pipe 30C
X is closed with the lid 35, and the inside of the pipe is filled with a liquid W such as water that can be frozen (filling step E). As the freezeable liquid W, water, ice, liquid paraffin, or the like can be used. next,
The entirety of the double pipe 30C is cooled by the refrigerator L to freeze the liquid W in the double pipe (freezing step F). Thereafter, the double pipe is bent to a desired angle by a bending means (pipe bender, press machine, etc.) M (bending step G). Finally, the entire pipe is heated and thawed by the dryer H1 or spontaneously thawed to remove the liquid from the inside of the double pipe 30C (water draining step H).

In the method of manufacturing the exhaust pipe 300 equipped with the catalyst pipe 20C, as shown in FIG. 6, the double pipe 30C has a large number of rhombic or turtle-shaped holes 23E formed in the inner pipe 23A. It is made of expanded material. After the double pipe 30C is frozen and then bent at a desired angle by a bending means (pipe bender, press machine, etc.) M in the bending step G, a diamond-shaped or turtle-shaped hole 23 is formed.
E is such that, for a bending force Fo in a direction perpendicular to the axial direction О, the outer diameter side of the bending is easily expanded and deformed in the axial direction 、, and the inner diameter side of the bending is easily reduced and deformed in the axial direction О. You. Therefore, since the cracks and wrinkles do not occur on the wall surface of the inner pipe 23A, the catalyst S baked on this surface does not peel off and can be easily bent to a desired angle Q.

According to the method of manufacturing the exhaust pipe 300 provided with the catalyst pipe serving as the inner pipe 23A, the exhaust pipe 1 is formed into the long bent exhaust pipe 1 connected to the exhaust port of the engine, or into a predetermined shape. One bendable long catalyst pipe 23A in the joint pipes 5, 7
Exhaust system pipe 30 which is provided through holding rings 17 at both ends thereof.
0 is formed.

As a result, the purifying action of the waste gas can be efficiently performed in a curved long path such as the exhaust pipe 1 having a high exhaust gas temperature, so that the purifying efficiency of the exhaust gas can be improved and the catalyst pipe can be mounted. The exhaust system pipe 300 can be manufactured at low cost.

Further, as shown in FIG. 7, an exhaust system pipe 400 in which the catalyst pipe of the fourth embodiment using the metal net 15A as the inner pipe may be mounted. The manufacturing method is the same as in the third embodiment. That is, in the process diagram of the manufacturing method shown in FIG. 3, instead of the punching metal 20 used in the second embodiment and the expanded metal 23 used in the third embodiment, an inner pipe 24 made of a wire mesh 15A is used. The catalyst S is supported, and holding rings 1 are provided at both ends.
7 is attached and inserted into the exhaust pipe 1 and the joint pipes 5 and 7 in the same manner as in the embodiment. The exhaust system pipe 400 of the present embodiment also has the same operation and effect as the exhaust system pipe provided with the catalyst pipe of the third embodiment.

FIG. 8 shows an exhaust pipe 200 according to the fifth embodiment in which a silencer K is interposed between the inner and outer pipes 10 and 20A in an exhaust pipe 200 using a punched metal as a catalyst pipe according to the second embodiment. The system pipe 500 is shown.
The fifth embodiment can be implemented by using another expanded metal 23 and a wire net 15. As the silencing material K, stainless wool or steel wool having high heat resistance is used.

According to the method for manufacturing an exhaust pipe equipped with the catalyst pipe, a silencing material is inserted into the annular gap between the inner and outer pipes at the time of or before the step of joining to the double pipe structure of the outer pipe and the inner pipe. Because the process to intervene is added,
Double pipe 30 of outer pipe 10 and inner pipe 20A
The silencing material K can be easily interposed in the structure A.

Exhaust pipe 500 equipped with the above catalyst pipe
In the case where a silencing material is interposed in the annular gap between the inner and outer pipes of the double pipe structure of the outer pipe and the inner pipe, when high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, The gas effectively expands from a number of long holes and the like to the silencing material, lowering the internal pressure, exhibiting an excellent silencing effect, and efficiently purifying the exhaust gas.

Further, the exhaust pipe 600 equipped with the catalyst pipe of the sixth embodiment shown in FIG. 9 is different from the exhaust pipe 500 equipped with the catalyst pipe of the fifth embodiment of FIG. It was done. In addition, a sound deadening material K is interposed between the inner and outer pipes. It should be noted that the present invention can be implemented by using another expanded metal 23 and a wire mesh body 15A.

According to the method of manufacturing an exhaust pipe equipped with a catalyst pipe according to the sixth embodiment, in the step of joining the inner pipe and the outer pipe to the structure of the double pipe 30A, the outer pipe 10 is connected to the outer cylindrical body 10A. And a straight tubular inner cylindrical body 10B in which a large number of long holes 10C are provided in a staggered manner in a direction perpendicular to the axial direction, and a large number of rhombic or turtle-shaped holes are provided. A straight tubular inner cylinder formed of an expanded material, and the inner cylinder is inserted with the sound deadening material K interposed in the outer cylinder, and the inner pipe 20A is inserted into the inner diameter side of the inner cylinder. To the structure of the triple pipe 40A.

Thus, when high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, it effectively expands in the triple pipe structure to reduce the internal pressure, and also exhibits an excellent noise reduction effect. In addition, it is possible to provide an exhaust pipe equipped with a catalyst pipe for purifying exhaust gas efficiently.

[0053]

According to the first aspect of the present invention, the wire mesh is formed in a cylindrical shape, and a holding ring is attached to one end of the cylindrical wire mesh, or a catalyst is supported on the wire mesh. Is performed before and after, and the cylindrical wire netting is bent into a predetermined shape from an end side having no holding ring into an exhaust pipe, or into a joint pipe bent and formed into a predetermined shape. A single bendable long catalyst pipe is installed inside an exhaust pipe that is bent long near the engine or a joint pipe that is bent into a predetermined shape by easily inserting and disposing while deforming along the inner surface It is possible to manufacture the exhaust pipe at low cost.

According to the present invention, the catalyst is supported on the cylindrical wire netting, and a holding ring is attached to one end of the wire netting. Since it is arranged in an exhaust pipe bent into a predetermined shape or a joint pipe bent into a predetermined shape, one pipe is inserted into a long exhaust pipe near the engine or a joint pipe bent into a predetermined shape. By using an exhaust pipe fitted with a long bendable catalyst pipe, the purification efficiency of exhaust gas can be improved.

According to the third aspect, the inside of the long bent exhaust pipe connected to the exhaust port of the engine,
An exhaust pipe in which one long bendable catalyst pipe is mounted via a holding ring at both ends thereof in a joint pipe bent into a predetermined shape can be easily obtained. As a result, an exhaust pipe equipped with a catalyst pipe having excellent exhaust gas purification efficiency can be manufactured at low cost.

According to a fourth aspect of the invention, a step of interposing a sound deadening material in the annular gap between the inner and outer pipes is added during or before the step of joining to the double pipe structure of the outer pipe and the inner pipe. When high-temperature and high-pressure exhaust gas from the air passes through the inner pipe, the exhaust gas effectively expands from a number of long holes to the silencing material, lowering the internal pressure and exhibiting an excellent silencing effect. The exhaust gas can be efficiently purified.

According to a fifth aspect of the present invention, in the step of joining the inner and outer pipes to a double pipe structure, the outer pipe includes an outer cylinder,
It is formed of a straight tubular inner cylinder body in which a number of long holes extending in a direction perpendicular to the axis direction installed in the inside are staggered, or an expanded material in which a number of diamond-shaped or turtle-shaped holes are drilled. And a straight pipe-shaped inner cylinder body, which can be joined to a triple pipe structure in which the inner cylinder body is inserted with the silencing material interposed in the outer cylinder body and the inner pipe is inserted on the inner diameter side of the inner cylinder body. .

As a result, when the high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, it effectively expands in the triple pipe structure to reduce the internal pressure, and also exhibits an excellent noise reduction effect. At the same time, the exhaust gas can be efficiently purified.

According to a sixth aspect of the present invention, as the inner pipe to be inserted inside the outer pipe, a plurality of long holes elongated in a direction perpendicular to the axial direction or an inner pipe of a wire netting formed in a cylindrical shape are staggered. A straight tubular inner pipe provided, or a straight tubular inner pipe formed of an expanded material formed by drilling a large number of diamond-shaped or turtle-shaped holes is employed. It is held inside the outer pipe via holding rings attached to both ends, and furthermore, since the inner and outer pipes are bent at an appropriate angle, the inside of a long bent exhaust pipe connected to the exhaust port of the engine and a predetermined shape An exhaust pipe in which one bendable long catalyst pipe is installed via a holding ring at both ends in a bent joint pipe, and efficiently exhausted in a long path in an exhaust pipe with high exhaust temperature. Purification action of the gas is performed, thereby improving efficiency of purifying the exhaust gas.

According to a seventh aspect of the present invention, a high-temperature and high-pressure exhaust gas from an engine flows through the inner pipe by interposing a silencer in an annular gap between the inner and outer pipes of the double pipe structure of the outer pipe and the inner pipe. When passing through, the exhaust gas effectively expands from a number of long holes and the like into the noise-reducing material, lowering the internal pressure, exhibiting an excellent noise-reducing effect, and purifying the exhaust gas efficiently.

According to an eighth aspect of the present invention, in the double pipe structure of the inner and outer pipes, the outer pipe has a plurality of long holes staggered in a direction perpendicular to the axial direction provided inside the outer cylinder. A straight tubular inner cylinder body, or a straight tubular inner cylinder body formed of an expanded material formed by drilling a large number of diamond-shaped or turtle-shaped holes, and a sound-absorbing material is interposed in the outer cylinder body. By inserting the inner cylinder body and changing to a triple pipe structure with an inner pipe inserted on the inner diameter side of this inner cylinder body, when high-temperature and high-pressure exhaust gas from the engine passes through the inner pipe, It effectively expands in the triple pipe structure to reduce the internal pressure, thereby obtaining an excellent noise reduction effect and an exhaust gas purification effect.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention, and is an external view of an exhaust device and a cross-sectional view of main parts.

FIG. 2 shows a first embodiment of the present invention and is a process diagram of a method of manufacturing an exhaust pipe equipped with a catalyst pipe.

FIG. 3 shows a second embodiment of the present invention and is a process diagram of a method of manufacturing an exhaust pipe equipped with a catalyst pipe.

FIG. 4 is an enlarged cross-sectional view of an exhaust pipe equipped with a catalyst pipe, showing a second embodiment of the present invention.

FIG. 5 shows a second embodiment of the present invention and is a partial cross-sectional view of a catalyst pipe.

FIG. 6 is an enlarged sectional view of an exhaust pipe equipped with a catalyst pipe, showing a third embodiment of the present invention.

FIG. 7 is an enlarged sectional view of an exhaust pipe equipped with a catalyst pipe according to a fourth embodiment of the present invention.

FIG. 8 is an enlarged sectional view of an exhaust pipe equipped with a catalyst pipe according to a fifth embodiment of the present invention.

FIG. 9 is an enlarged cross-sectional view of an exhaust pipe equipped with a catalyst pipe according to a sixth embodiment of the present invention.

FIG. 10 is a side view showing the appearance of a conventional exhaust device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Exhaust pipe 5, 7 Joint pipe 9 Silencer 10 Outer pipe 10A Outer cylinder 10B Inner cylinder 10C Long hole 11 Catalyst pipe 15 Wire mesh 15A Wire mesh 17 Holding ring 19 Catalyst bath 19A Diamond-shaped or turtle-shaped hole 20 Punching metal 20A Inner pipe (catalyst pipe) 20B Slot 23 Expanded metal 23A Inner pipe (catalyst pipe) 23E Hole 30A Double pipe 30C Double pipe 40A Triple pipe 35 Lid 50 Silencer A Pipe forming process B Retaining ring mounting process C Process D Joining process E Filling process F Freezing process G Bending process H Draining process K Silencer L Refrigerator H Heater H1 Dryer M Bending means O Axial direction S Catalyst W Liquid

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F01N 7/18 F01N 7/18 F16L 9/18 F16L 9/18 11/12 11/12 Z F term (reference 3G004 AA02 CA13 DA14 EA03 FA01 FA04 GA01 3G091 AA03 AB01 BA00 BA38 BA39 GA02 GA04 GB01X HA31 HB01 3H111 AA01 BA01 CA12 CA57 CB02 DA26 DB11

Claims (8)

[Claims] 1. The method according to claim 1, wherein the wire mesh is formed into a cylindrical shape, and a holding ring is provided at one end of the cylindrical wire mesh, or a catalyst is carried on the wire mesh. A catalyst pipe, wherein the cylindrical wire netting is inserted and arranged in an exhaust pipe bent into a predetermined shape from a distal end side having no holding ring or a joint pipe bent in a predetermined shape. Of manufacturing exhaust system pipes. 2. An exhaust formed by supporting a catalyst on a cylindrical wire netting, attaching a holding ring to one end of the wire netting, and bending the wire netting into a predetermined shape from a tip end side without the holding ring. An exhaust pipe equipped with a catalyst pipe, which is inserted and arranged in a pipe or a joint pipe bent into a predetermined shape. 3. An inner pipe of a metal mesh body formed in a cylindrical shape,
Or, a straight tubular inner pipe in which a number of long holes extending in a direction perpendicular to the axis direction are drilled in a staggered manner, or a straight tubular inner pipe formed of an expanded material in which a number of diamond-shaped or turtle-shaped holes are drilled. The step of attaching the retaining rings to both ends of the pipe, or the step of supporting the catalyst on the inner pipe, is performed before and after, and then, the straight inner pipe is placed in the outer outer pipe. Inserting and joining the inner and outer pipes to the double pipe structure, closing one end of the double pipe with a lid, filling the pipe with a liquid that can be frozen, and cooling the entire double pipe And freezing the liquid in the double pipe, bending the double pipe to a desired angle with a bending means, and draining the liquid from inside the double pipe. Of the exhaust pipe with the catalyst pipe Production method. 4. A step of interposing a sound deadening material in an annular gap between the inner and outer pipes at the time of or before the step of joining to the double pipe structure of the outer pipe and the inner pipe. 4. A method for producing an exhaust pipe equipped with the catalyst pipe according to 3. 5. In the step of joining the inner and outer pipes to the double pipe structure, the outer pipe has a staggered number of long holes extending in a direction perpendicular to an axial direction provided inside the outer cylinder. It consists of a perforated straight tubular inner cylinder, or a straight tubular inner cylinder formed of an expanded material formed by drilling a large number of diamond-shaped or turtle-shaped holes, with a sound deadening material interposed in the outer cylinder. 4. The method for manufacturing an exhaust pipe with a catalyst pipe according to claim 3, wherein the inner pipe is inserted into the inner pipe, and the inner pipe is joined to a triple pipe structure in which an inner pipe is inserted on the inner diameter side. 6. The inner pipe inserted inside the outer pipe may be a cylindrical inner wire of a metal mesh body, or a straight wire having a plurality of long holes elongated in a direction perpendicular to the axial direction in a staggered manner. A tubular inner pipe, or a straight tubular inner pipe formed of an expanded material formed by drilling a number of diamond-shaped or turtle-shaped holes, the inner pipe carrying a catalyst and attached to both ends of the inner pipe An exhaust pipe mounted with a catalyst pipe, wherein the exhaust pipe is held inside the outer pipe via a holding ring, and the inner and outer pipes are bent at an appropriate angle. 7. An exhaust pipe equipped with a catalyst pipe according to claim 6, wherein a sound deadening material is interposed in an annular gap between the outer pipe and the inner pipe. 8. The outer pipe comprises an outer cylinder, an inner cylinder of a cylindrical metal mesh body provided inside the outer cylinder, or a plurality of long holes elongated in a direction perpendicular to the axial direction. A perforated straight tubular inner cylinder, or a straight tubular inner cylinder formed of an expanded material formed by perforating a large number of diamond-shaped or turtle-shaped holes,
7. A triple pipe structure in which a silencer is interposed in an annular gap between the outer cylinder and the inner cylinder, and an inner pipe is inserted on the inner diameter side of the inner cylinder.
An exhaust pipe equipped with the catalyst pipe described in the above.