JP2017025815A - Connection structure of exhaust emission control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection structure of an exhaust emission control device capable of reducing a weight and costs with a simple structure and to improve mountability onto a vehicle, in connecting and supporting casings.SOLUTION: With respect to a connection structure of an exhaust emission control device holding a purification material (particulate filter 5, selective reduction type catalyst 6, oxidation catalyst 11, ammonia reduction catalyst 12) for purifying an exhaust gas 3, inside of casings 7, 8 disposed on the way of an exhaust pipe 4, connection members 24 including welded patches 24a configuring faces along the surfaces of the casings 7, 8 and welded to the surfaces of the casings 7, 8, and connection flanges 24b projecting to the surfaces of the welded patches 24a, are disposed on the surfaces of the casings 7, 8, and the casings 7, 8 are connected through the connection members 24.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a structure for connecting and supporting an exhaust emission control device of a vehicle.

  Since exhaust gas discharged from a diesel engine contains particulate matter (particulate matter), NOx, etc., a particulate filter or oxidation catalyst is placed in the middle of the exhaust pipe through which exhaust gas from the diesel engine flows. It has been practiced to purify particulates and NOx with a purifying material such as a selective reduction catalyst.

  FIG. 4 shows an example of such an exhaust emission control device, and shows a compact exhaust emission control device created by the present inventor and already filed as Japanese Patent Application No. 2007-29923. In the exhaust emission control device in this already-filed application, a particulate filter 5 that collects particulates in the exhaust gas 3 in the middle of the exhaust pipe 4 through which the exhaust gas 3 discharged from the diesel engine 1 through the exhaust manifold 2 flows. And a selective reduction catalyst 6 having the property of selectively reacting NOx with ammonia even in the presence of oxygen on the downstream side of the particulate filter 5 and held in parallel by casings 7 and 8, respectively. At the same time, the rear end portion of the particulate filter 5 and the front end portion of the selective catalytic reduction catalyst 6 are connected by a communication channel 9 having an S-shaped structure, and the exhaust gas 3 discharged from the rear end portion of the particulate filter 5. Is folded forward and introduced into the front end portion of the adjacent selective catalytic reduction catalyst 6.

  As shown in an enlarged view in FIG. 5, the communication channel 9 surrounds the rear end of the particulate filter 5, and the exhaust gas 3 immediately after exiting from the rear end collides with the wall surface to make a substantially right angle. A gas collecting chamber 9A that collects while changing its direction, and a mixing pipe 9B that extracts the exhaust gas 3 collected in the gas collecting chamber 9A forward and includes an injector 10 for adding urea water in the middle of the exhaust pipe 3; The exhaust gas 3 guided forward by the mixing pipe 9B collides with the wall surface and is dispersed in a substantially perpendicular direction, and the dispersed exhaust gas 3 is introduced into the front end portion of the selective catalytic reduction catalyst 6. Thus, an S-shaped structure is formed by the gas dispersion chamber 9C surrounding the front end portion.

  In addition to the two purification materials (particulate filter 5 and selective reduction catalyst 6) described above, an unburned fuel component in the exhaust gas 3 is provided in the front stage in the casing 7 in which the particulate filter 5 is held. An oxidation catalyst 11 for oxidizing the catalyst, and an ammonia reduction catalyst 12 for oxidizing excess ammonia are provided as purification materials in the rear stage of the casing 8 in which the selective catalytic reduction catalyst 6 is held. Yes.

  If such a configuration is employed, particulates in the exhaust gas 3 are collected by the particulate filter 5, and a urea water addition injector (urea water addition means) is provided in the middle of the mixing pipe 9B on the downstream side. 10) Urea water is added to the exhaust gas 3 from 10 and thermally decomposed into ammonia and carbon dioxide, and the NOx in the exhaust gas 3 is reduced and purified well by ammonia on the selective catalytic reduction catalyst 6. As a result, the exhaust gas 3 Simultaneous reduction of the particulates and NOx in the inside will be achieved.

  At this time, the exhaust gas 3 discharged from the rear end portion of the particulate filter 5 is folded forward by the connecting flow path 9 and then introduced into the front end portion of the adjacent selective catalytic reduction catalyst 6. A long distance from the urea water addition position in the middle of the communication flow path 9 to the selective catalytic reduction catalyst 6 is ensured, and the flow of the exhaust gas 3 is turned back to make it turbulent, resulting in urea water and exhaust gas. As a result of promoting the mixing with 3, the reaction time sufficient to produce ammonia from the aqueous urea is ensured.

  In addition, the particulate filter 5 and the selective catalytic reduction catalyst 6 are arranged in parallel, and the connecting flow path 9 is arranged between the particulate filter 5 and the selective catalytic reduction catalyst 6, so that the whole The configuration becomes compact, and the mountability to the vehicle is greatly improved.

  By the way, in this kind of exhaust gas purification apparatus, the mixing pipe 9B of the communication flow path 9 located between the front and rear casings 7 and 8 is likely to crack. The casings 7 and 8 holding the purification material inside are heavy, and when the casings 7 and 8 try to displace each other due to vibration or thermal expansion accompanying operation, the mixing pipe 9B sandwiched between them is twisted. This is because stress is generated. In order to prevent damage to the mixing pipe 9B due to this stress, it is necessary to connect and fix the casings 7 and 8 so as not to be displaced from each other, and to increase the rigidity of the exhaust purification apparatus as a whole.

  In the case of the example shown in FIG. 5, flanges 13, 14, 15, 16, 17, 18, 19, 20 are provided at the division positions in the casings 7, 8 or the connection positions with the communication flow path 9. The eight flanges are connected by connecting brackets 21 and 22 so as to bridge between the casings 7 and 8 so that the casings 7 and 8 are fixed to each other. That is, the casing 7 is divided at a position immediately before the oxidation catalyst 11 and connected by fastening flanges 13 and 14 welded to the divided end faces, and the particulate filter 5 in the casing 7 is connected. The rear end surface immediately after that is connected to the gas collecting chamber 9A by fastening the flange 15 welded to the rear end surface and the flange 16 welded to the front end surface of the gas collecting chamber 9A to each other. Similarly, the casing 8 is divided at a position immediately after the ammonia reducing catalyst 12 and is connected by fastening flanges 19 and 20 welded to the divided end faces, and the selective reduction in the casing 8 is also performed. The front end surface immediately before the catalyst 6 is connected to the gas dispersion chamber 9C by fastening the flange 18 welded to the front end surface and the flange 17 welded to the rear end surface of the gas dispersion chamber 9C. A connecting bracket 21 is provided so as to overlap the flanges 15 and 16 on the casing 7 side and the flanges 19 and 20 on the casing 8 side, and the flanges 15 and 16 and the flanges 19 and 20 are fastened to the connecting bracket 21. A connecting bracket 22 is provided so as to overlap the flanges 13 and 14 on the casing 7 side and the flanges 17 and 18 on the casing 8 side, and the flanges 13 and 14 and the flanges 17 and 18 are fastened to the connecting bracket 22. Thus, the flanges 13, 14, 15, 16 on the casing 7 side and the flanges 17, 18, 19, 20 on the casing 8 side are connected to each other via the connection brackets 21, 22, and the rigidity of the exhaust emission control device as a whole. So that the casings 7 and 8 are not displaced from each other.

  Moreover, as shown in FIG. 6, the upper part of the said flange (flange 13, 14, 15, 16, 17, 18, 19, 20) is connected with the suspending member 23 with which the vehicle side was equipped, thereby, exhaust-gas purification apparatus. The whole is supported by the vehicle. 6 shows the structure of the connection bracket 21 and the flanges 15, 16, 19, and 20 side, the connection bracket 22 and the flanges 13, 14, 17, and 18 are also supported on the vehicle side by the same structure. The

  The eight flanges are usually about 5 to 6 times thicker than the materials of the casings 7 and 8 in order to ensure strength and rigidity. Specifically, for example, the plate thickness of the casings 7 and 8 is about 1 to 2.5 [mm], and the plate thickness of the flange is about 6 to 12 [mm].

  As a technical document related to the connection structure of the exhaust purification apparatus as described above, for example, there is Patent Document 1 below.

JP 2009-74420 A

  In the above-described conventional structure, the eight flanges connect the parts of the divided casings 7 and 8, the gas collecting chamber 9A, and the gas dispersion chamber 9C, as well as connecting the casings 7 and 8, and the vehicle. It also serves as a supporting role. Therefore, even if it is not necessary to divide the parts of the casings 7 and 8, the gas collecting chamber 9A, and the gas dispersion chamber 9C (therefore, it is not necessary to connect the parts by the flange), the casing 7, For the purpose of connecting the eight, it was necessary to provide a flange. In providing the flange for connecting and supporting the casings 7 and 8, the flange needs to be set thick as described above, and the casings 7 and 8 in which the purifier is accommodated have a large diameter. For this reason, there is a problem in that the weight of the flange increases and the material cost increases. In addition, the flange projecting in the entire circumferential direction of the casings 7 and 8 easily interferes with peripheral devices, and there is a problem that the mounting position and posture of the exhaust purification device in the vehicle are limited.

  In view of such circumstances, the present invention intends to provide a connection structure for an exhaust emission control device that can reduce weight and cost with a simple structure and can improve mounting on a vehicle when connecting and supporting a casing. It is.

  The present invention relates to a connection structure of an exhaust purification device in which a purification material for purifying exhaust gas is held inside a casing provided in the middle of an exhaust pipe, and is connected to the surface of the casing. A connecting member having a weld patch that is welded to the surface of the casing in a plane along the surface and a connecting flange that protrudes from the surface of the welding patch, and the casing is connected via the connecting member; The present invention relates to a connecting structure of an exhaust emission control device characterized in that it is configured as described above.

  In this way, the casing can be connected and supported by partially providing a connecting flange at a place where connection or support is required, without providing a flange around the entire circumference, and the material cost as well as the weight can be increased. Can be reduced. Further, since the connecting flange does not protrude over the entire circumference of the casing, there are few restrictions on the mounting position and posture with respect to the vehicle.

  In the connection structure of the exhaust gas purification apparatus of the present invention, the purification material is preferably held in the casing via a heat-insulating filler, and in this way, a welding patch is applied to the surface of the casing. Can be prevented from being damaged by heat or a back bead.

  In the connection structure of the exhaust emission control device according to the present invention, the connection member has a plate thickness of the weld patch of 1.5 to 4 times the plate thickness of the casing body, and the connection flange has a plate thickness. It is preferable that the thickness is 1.5 times or more and 4 times or less with respect to the plate thickness of the weld patch. In this way, the plate thickness of each material is gradually reduced in the order of the casing body, the weld patch, and the connecting flange. As a result, the stress generated when the casings try to displace each other is appropriately distributed among the materials.

  The exhaust purification device connection structure of the present invention includes a plurality of the purifying materials held by two casings and arranged in parallel so that the inlet end portions of the casings face in the same direction. The present invention is applied to an exhaust gas purification apparatus having an S-shaped connecting flow path that folds exhaust gas discharged from the outlet end portion of a casing in a reverse direction and introduces the exhaust gas into the inlet end portion of the other adjacent casing. The two casings can be connected and fixed via the connecting member.

  According to the connection structure of the exhaust emission control device of the present invention, the following various excellent effects can be obtained.

  (I) According to the invention described in claim 1 of the present invention, when connecting and supporting the casing, the weight and cost can be reduced with a simple structure, and the mountability to the vehicle can be improved.

  (II) According to the invention described in claim 2 of the present invention, since the welding patch can be welded to the surface of the casing regardless of the position, the overall length of the exhaust purification device can be shortened and mounted on the vehicle. In addition to improving the performance, it is possible to optimize the mounting position of the connecting member to the casing in consideration of rigidity and balance.

  (III) According to the invention described in claim 3 of the present invention, as a result of the stress being appropriately distributed between the respective members constituting the casing body and the connecting member, the durability of the casing body and the connecting member is improved. be able to.

  (IV) According to the invention described in claim 4 of the present invention, it is possible to ensure rigidity in the exhaust purification device having the S-shaped connecting flow path in a compact form by the connecting member.

It is a figure which shows the Example of this invention. It is sectional drawing which shows the Example of this invention, and is the II-II arrow equivalent view of FIG. It is a figure which expands and shows the connection member used for this invention, (A) is a perspective view of the state attached to the casing, (B) is sectional drawing equivalent to the IIIB-IIIB arrow of (A). It is the schematic which shows an example of the whole structure of an exhaust gas purification apparatus. It is a figure which shows an example of the conventional exhaust gas purification apparatus. It is sectional drawing which shows an example of the conventional exhaust gas purification apparatus, and is a VI-VI arrow equivalent view of FIG.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 to 3 show an example of a connection structure of an exhaust emission control device according to an embodiment of the present invention. In the figure, parts denoted by the same reference numerals as in FIGS. 4 to 6 represent the same thing. Yes.

  The basic configuration of the present embodiment is the same as that of the conventional one shown in FIGS. 4 to 6. As shown in FIG. 1, the particulate filter 5 and its downstream are located in the middle of the exhaust pipe 4 through which the exhaust gas 3 flows. Side selective reduction catalyst 6 is held in parallel by casings 7 and 8, and the S-shaped structure is connected between the rear end of particulate filter 5 and the front end of selective reduction catalyst 6. The exhaust gas 3 is connected by a flow path 9 and exhausted from the rear end of the particulate filter 5 is folded forward and introduced into the front end of the adjacent selective catalytic reduction catalyst 6. The communication flow path 9 is configured to form an S-shaped structure by the gas collecting chamber 9A, the mixing pipe 9B, and the gas dispersion chamber 9C. An oxidation catalyst 11 is provided in the front stage in the casing 7 in which the particulate filter 5 is held, and an ammonia reduction catalyst 12 is provided in the rear stage in the casing 8 in which the selective reduction catalyst 6 is held. Has been.

  In the case of this embodiment, instead of the eight flanges in the conventional structure (see FIGS. 5 and 6), the connecting members 24 as shown in FIG. . Each connecting member 24 includes a weld patch 24a that is welded to the surface of the casing 7, 8 along a surface along the surface of the casing 7, 8, and a connecting flange 24b that protrudes from the surface of the weld patch 24a. Prepare. 1 and 2, the connecting flanges 24b of the connecting members 24 provided on the opposing surfaces of the casings 7 and 8 are connected by connecting brackets 21 and 22, and the casings 7 and 8 are connected to each other and fixed. At the same time, as shown in FIG. 2, the connecting flange 24b of the connecting member 24 provided on the upper surface of the casings 7 and 8 is connected to the suspension members 23 and 23 on the vehicle side. Supports hanging.

  Further, in this embodiment, as shown in FIG. 2, the particulate filter 5 and the selective reduction catalyst 6 are accommodated in the casings 7 and 8 via the filler 25. The filler 25 is made of a material having sufficient heat resistance and heat insulation, such as ceramic fiber.

Welding patch 24a constituting the connecting member 24, the thickness of each timber of the connecting flange 24b is set as shown in FIG. 3 (B), relative to the thickness t ₁ of the body of the material of the casing 7 or 8 4 times the plate thickness _{t 2} is 1.5 times or more of welding the patch 24a or less, further, the thickness _{t 3} of the connecting flange 24b relative to the thickness _{t 2} of the welding patch 24a and the following 4 times 1.5 times It has become. In other words, if this relationship is expressed as a formula,
[Equation 1]
t ₁ <t ₂ <t ₃
And
[Equation 2]
1.5 ≦ t ₂ / t ₁ ≦ 4
1.5 ≦ t ₃ / t ₂ ≦ 4
It can be expressed. Thus, the plate thicknesses t ₁ , t ₂ , and t ₃ are set so as to gradually increase in order of the material of the casings 7 and 8, the welding patch 24 a, and the connecting flange 24 b, specifically, For example, t ₁ = 1.5 [mm], t ₂ = 3 [mm], and t ₃ = 8 [mm] can be set.

  Thus, if the casings 7 and 8 of the exhaust emission control device are connected by using such a connecting member 24, it is necessary to connect not the flanges of the entire circumference as in the conventional structure (see FIGS. 5 and 6). The casings 7 and 8 can be supported by partially providing the connecting flange 24b only at the locations. Thereby, the material cost can be reduced as well as the weight of the exhaust emission control device as compared with the case where the entire circumference flange as in the conventional structure is provided.

  Further, since the connecting flange 24b does not protrude over the entire circumference of the casings 7 and 8, there are fewer restrictions on the mounting position and posture with respect to the vehicle compared to the conventional structure in which the flange extends over the entire circumference. For example, as shown in FIG. 2, when the exhaust purification device is supported near the frame 26 of the vehicle, the exhaust purification device is attached to the frame 26 as much as the connecting flange 24b does not protrude all around as compared with the conventional structure shown in FIG. And the exhaust purification device can be arranged at a location closer to the frame 26.

  Further, in the casings 7 and 8, a purifying material (particulate filter 5, selective reduction catalyst 6, oxidation catalyst 11, ammonia reduction catalyst 12), which is contained in the casings 7 and 8, is filled with a heat insulating material. Hugging through 25. For this reason, the welding patch 24a of the connecting member 24 can be welded to the portion of the casing 7 or 8 in which the purification material is accommodated, and the position where the connecting member 24 is attached need not be selected. .

  That is, in the above-described conventional structure shown in FIGS. 5 and 6, the flange is attached by welding to the entire circumference of the casings 7 and 8, but welding is performed to the casing in which the purification material is accommodated. And there exists a possibility that the said purification | cleaning material may be damaged by the back bead which arises with the heat of welding or welding. Therefore, it is necessary to shift the installation position of the flange from the position where the purification material is accommodated. For this reason, the total length of the exhaust gas purification device becomes longer by the amount of the flange, which has been a factor that hinders the compactness and mountability of the device.

  On the other hand, in the case of the present embodiment, when welding the weld patch 24a to the surface of the casing 7, 8, even if welding is performed on the portion where the purifying material is accommodated, the heat of welding is blocked by the filler 25, Since it is not transmitted to the internal purification material, there is no concern that the purification material will be damaged by heat. Moreover, since the filler 25 also absorbs deformations such as the back bead generated on the back surfaces of the casings 7 and 8 due to welding, physical damage to the internal purification material is also prevented. Therefore, when welding the weld patch 24a to the surfaces of the casings 7 and 8, there is no need to select a position to attach.

  That is, in this embodiment, there is no need to install a flange avoiding the portion where the purification material is accommodated in the casings 7 and 8 as in the conventional structure shown in FIG. 5, and the casings 7 and 8 as shown in FIG. Since the connecting flange 24b can be provided on the surface of the purifying material accommodating portion, the total length of the exhaust purifying device is not increased by the amount of the flange formed as in the conventional structure. It can be made compact.

  Further, since the connecting member 24 can be attached at any position of the casings 7 and 8 other than the position shown in FIG. 1, the attachment position can be optimized in consideration of rigidity and balance. it can. That is, the connection flange 24b can be provided at a convenient position without being influenced by the position of the purifying material, so that the casings 7 and 8 are suspended and supported on the vehicle at the most balanced position, It is possible to connect and fix the eight members at a position where the rigidity as the exhaust gas purification device is highest.

As described above, the connecting member 24 has a plate thickness (t ₁ , t ₂ , t ₃ ) of 1.5 times or more and 4 times or less in the order of the material of the casings 7 and 8, the welding patch 24 a, and the connecting flange 24 b. It is set so as to increase gradually and gradually in the range (see FIG. 3B). Thus, when the plate thickness of each material is set so as to gradually change in the order of t ₁ , t ₂ , t ₃ , when the casings 7 and 8 try to displace each other due to vibration or thermal expansion accompanying operation. Is appropriately distributed among the materials. As a result, the durability of the casings 7 and 8 and the connecting member 24 can be improved.

  As described above, in the present embodiment, the purification materials (the particulate filter 5, the selective reduction catalyst 6, the oxidation catalyst 6) for purifying the exhaust gas 3 are disposed in the casings 7 and 8 provided in the middle of the exhaust pipe 4. The exhaust gas purifying apparatus has a catalyst 11 and an ammonia reduction catalyst 12). The casing 7, 8 has a surface along the surface of the casing 7, 8 on the surface of the casing 7, 8. A connecting member 24 having a welding patch 24 a welded to the surface of the welding patch 24 and a connecting flange 24 b protruding from the surface of the welding patch 24 a is arranged, and the casings 7 and 8 are connected via the connecting member 24. Therefore, the casings 7 and 8 can be connected and supported partially by providing the connection flange 24b at the places where connection and support are required without providing flanges on the entire circumference, and the cost of the material can be increased. Can also be reduced. Further, since the connecting flange 24b does not protrude over the entire circumference of the casing 7, 8, there are few restrictions on the mounting position and posture with respect to the vehicle. Therefore, when the casings 7 and 8 are connected and supported, the weight and cost can be reduced with a simple structure, and at the same time, the mounting property to the vehicle can be improved.

  In the present embodiment, the purifying material (the particulate filter 5, the selective reduction catalyst 6, the oxidation catalyst 11, and the ammonia reduction catalyst 12) is held in the casings 7 and 8 through the filler 25 having heat insulation properties. Therefore, when the welding patch 24a is welded to the surfaces of the casings 7 and 8, it is possible to prevent the purification material inside the casings 7 and 8 from being damaged by heat or a back bead. For this reason, the welding patch 24a can be welded to the surfaces of the casings 7 and 8 regardless of the position, and as a result, the exhaust purification device can be shortened in total length to improve mountability on the vehicle, Considering the balance, it is possible to optimize the mounting position of the connecting member 24 to the casings 7 and 8.

Further, in this embodiment, the connecting member 24, the thickness _{t 2} of the welding patch 24a is equal to or less than 4-fold 1.5-fold or more relative to the thickness _{t 1} of the casing 7,8 body, a plate of the connecting flange 24b since the thickness _{t 3} is less than 4 times 1.5 times or more relative to the thickness _{t 2} of the welding patches 24a, stage the thickness of each timber is casings 7,8 body, welding patches 24a, in the order of connection flanges 24b As a result, the stress generated when the casings 7 and 8 try to displace each other is appropriately distributed between the respective materials. Thereby, durability of the casings 7 and 8 and the connecting member 24 can be improved.

  Further, in the present embodiment, the above-described exhaust purification device connection structure is formed by using a plurality of the purification materials (particulate filter 5, selective reduction catalyst 6, oxidation catalyst 11, ammonia reduction catalyst 12) as two casings 7. , 8 are arranged in parallel so that the inlet ends of the casings 7 and 8 face in the same direction, and the exhaust gas 3 discharged from the outlet end of one casing 7 is reversed. The present invention is applied to an exhaust gas purification apparatus provided with an S-shaped connecting flow path 9 that is folded and introduced into the inlet side end portion of the other casing 8 adjacent to the other casing 8. Since the exhaust purification device having the S-shaped connecting flow path 9 can ensure the rigidity in a compact form by the connecting structure via the connecting member 24. .

  In addition, the connection structure of the exhaust gas purification apparatus of the present invention is not limited to the above-described embodiment, and a type of exhaust gas purification in which two casings holding the purification material are arranged in parallel as in the above embodiment. It is possible to make various changes within a range not departing from the gist of the present invention, such as not only the apparatus but also any type of exhaust purification apparatus that holds the purification material in the casing. Of course.

3 Exhaust gas 4 Exhaust pipe 5 Purifier (Particulate filter)
6 Purification material (selective reduction catalyst)
7 Casing 8 Casing 9 Connecting flow path 11 Purification material (oxidation catalyst)
12 Purification material (ammonia reduction catalyst)
24 connecting member 24a welding patch 24b connecting flange t ₁ plate thickness t ₂ plate thickness t ₃ plate thickness

Claims (4)

A connection structure of an exhaust purification device having a purification material for purifying exhaust gas inside a casing provided in the middle of the exhaust pipe,
On the surface of the casing, a connecting patch comprising a weld patch welded to the surface of the casing in a plane along the surface of the casing, and a connecting flange projecting on the surface of the weld patch is disposed, A structure for connecting an exhaust purification device, wherein the casing is connected via the connecting member.   The exhaust purification device connection structure according to claim 1, wherein the purification material is held in the casing via a filler having a heat insulating property.   The connecting member has a plate thickness of the welding patch of 1.5 to 4 times the plate thickness of the casing body, and a plate thickness of the connecting flange of 1. It is 5 times or more and 4 times or less, The connection structure of the exhaust gas purification apparatus of Claim 1 or 2 characterized by the above-mentioned.   Exhaust gas that is held in parallel by the two casings so that the inlet ends of the casings face in the same direction and are discharged from the outlet end of one of the casings. 4. The exhaust emission control apparatus according to claim 1, wherein the exhaust gas purification apparatus includes an S-shaped connection flow path that folds gas in a reverse direction and introduces the gas into an inlet side end of the other casing. A connection structure of an exhaust gas purification apparatus, wherein the connection structure of the exhaust gas purification apparatus is applied and the two casings are connected and fixed via the connection member.

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