JP2005194949A - Emission control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an emission control device whose oxidation catalyst can be removed from a filter case together with a particulate filter and can be easily cleaned. <P>SOLUTION: The filter case 7 is divided into three sections of a front part 12, an intermediate part 13, and a rear part, and they can be mutually connected. The intermediate part 13 itself is a cartridge shell constituted by integrally holding the oxidation catalyst 17 and a particulate filter 6, and the intermediate part 13 can be connected with the front part 12 with a state where the front portion of the cartridge shell is inserted into the front part 12 with a required clearance C. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an exhaust emission control device.

  Particulate matter (particulate matter) discharged from a diesel engine is mainly composed of soot composed of carbonaceous matter and SOF content (Soluble Organic Fraction) composed of high-boiling hydrocarbon components. As shown in FIG. 4, an exhaust pipe 4 through which the exhaust gas 3 from the diesel engine 1 circulates as a measure for reducing this kind of particulates. The exhaust pipe 4 has a composition containing a small amount of sulfate (mist-like sulfuric acid component). It is considered that a particulate filter 6 is provided in the middle of the above.

  In the example shown here, an oxidation catalyst is integrated in a muffler 5 of an exhaust pipe 4 through which exhaust gas 3 discharged from a diesel engine 1 (internal combustion engine) of an automobile through an exhaust manifold 2 flows. The case where the catalyst regeneration type particulate filter 6 that is supported by the carrier is accommodated is illustrated, and the filter case 7 that holds the particulate filter 6 forms an outer cylinder of the muffler 5. .

  That is, as shown in an enlarged view in FIG. 5, an accommodation space of a required size defined by the dispersion plates 10 and 11 having a large number of communication holes is secured between the inlet pipe 8 and the outlet pipe 9 of the muffler 5. The particulate filter 6 is accommodated in the accommodation space.

  This particulate filter 6 has a porous honeycomb structure made of ceramic, and the inlets of the respective flow paths 6a partitioned in a lattice pattern are alternately sealed, and the flow paths 6a are not sealed. The outlet is sealed, and only the exhaust gas 3 that has permeated through the porous thin wall 6b partitioning each flow path 6a is discharged downstream.

  Then, the particulate matter collected on the inner surface of the porous thin wall 6b in the particulate filter 6 is removed by self-combustion in the operating region where the exhaust temperature is high, or if necessary, the particulate filter. The HC (hydrocarbon) added to the upstream side of 6 is burned and removed with the assistance of the reaction heat generated by the oxidation reaction in the oxidation catalyst 17 in the previous stage. Since the ash generated by the in-cylinder combustion from the lubricating oil gradually accumulates, it is necessary to clean the particulate filter 6 directly with high-pressure hot water or the like.

  For this reason, the filter case 7 is divided into a front part 12, an intermediate part 13 and a rear part 14, and a structure in which the parts are detachably fastened by bolts 15 and nuts 16 via flanges 12a, 13a, 14a, The particulate filter 6 can be appropriately removed and cleaned together with the intermediate portion 13.

  In the figure, 18 is an end plate for engaging the outer edges of the entrance end face and the exit end face of the oxidation catalyst 17 and the particulate filter 6 to restrain the movement in the axial direction, 19 is a cushion material, 20 is A sealing material 21 indicates a heat insulating material such as glass wool mounted on the outer periphery of the filter case 7.

As prior art document information related to the present invention, there are the following Patent Document 1, Patent Document 2, and the like.
JP 2003-172121 A JP 2003-97248 A

  However, as illustrated in FIG. 5, conventionally, only the particulate filter 6 is removed and washed together with the intermediate portion 13, so that the oxidation catalyst 17 remains in the front portion 12 of the filter case 7. There was a problem that the oxidation catalyst 17 could not be cleaned well with a dedicated automatic cleaning apparatus (Japanese Patent Application No. 2003-25856) as previously filed by the same applicant as the present invention.

  That is, the oxidation catalyst 17 remaining on the front portion 12 of the filter case 7 cannot be washed away well due to the equipment such as the inlet pipe 8 being in the way, so that it can be moved to the washing stand of the dedicated automatic washing apparatus as described above. Therefore, it was difficult to satisfactorily clean the oxidation catalyst 17 with the current divided structure.

  In general, it has been considered that the oxidation catalyst 17 is less likely to be clogged with soot and the like, but the front end side of the oxidation catalyst 17 is compared with the rear end side whose activity is enhanced by reaction heat such as added HC. Since it is difficult to increase the temperature, it cannot be denied that clogging may occur on the front end side of the oxidation catalyst 17 by continuing the operation state in which a large amount of soot is generated. It is desired to be able to wash together with the particulate filter 6.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an exhaust emission control device in which an oxidation catalyst can be removed from a filter case together with a particulate filter and easily cleaned.

  The present invention relates to an exhaust gas purification apparatus that can remove particulates in exhaust gas by passing the exhaust gas through a particulate filter installed in a filter case in the middle of the exhaust pipe, and an oxidation catalyst in a stage preceding the particulate filter. Are arranged in series, and these oxidation catalyst and particulate filter are integrally held by a cartridge shell, and the cartridge shell is configured to be detachable from the filter case.

  Thus, the oxidation catalyst and the particulate filter can be collectively removed from the filter case together with the cartridge shell, and the cartridge shell can be easily cleaned using a dedicated automatic cleaning device or the like. In addition, the cartridge shell can be mounted on this type of dedicated automatic cleaning apparatus, and the handling becomes easy.

  In carrying out the present invention, the filter case is divided into a front part, an intermediate part, and a rear part so that they can be connected to each other. It is good to comprise so that the said intermediate part and the said front part or the rear part may be connected in the state which inserted any one site | part through the said front part or the rear part via the required clearance.

  In this way, it is possible to remove the oxidation catalyst and the particulate filter together from the filter case together with the intermediate part only by releasing the connection between the front part, the intermediate part, and the rear part of the filter case. In this connected state, either one of the front and rear portions of the intermediate portion is inserted into the front portion or the rear portion through a required clearance, and this air insulation layer is formed by this clearance. It is not necessary to attach a heat insulating material such as glass wool around the outside.

  Furthermore, in the present invention, the filter case is divided into a front part and a rear part so that they can be connected to each other, and the entire cartridge shell is mounted in a state where it is inserted into the front part or the rear part through a required clearance. In addition, the mounting state may be fixed by connecting the front part and the rear part.

  In this way, it is possible to remove the oxidation catalyst and the particulate filter from the filter case by simply releasing the connection between the front part and the rear part of the filter case and extracting the cartridge shell from the front part or the rear part. In addition, in the mutually connected state, the entire cartridge shell is inserted into the front part or the rear part via a required clearance, and therefore, an air heat insulating layer is formed by this clearance, It is not necessary to attach a heat insulating material such as glass wool around the outside.

  In the present invention, an inner shell into which the cartridge shell can be inserted and mounted is fixedly installed in the filter case, and an outlet is provided at an appropriate position of the filter case so that the cartridge shell can be inserted into and removed from the inner shell from the outside. The cartridge shell mounted on the inner shell may be configured to be openable and closable so that the mounted state of the cartridge shell is fixed by closing the outlet.

  If it does in this way, it will become possible to remove an oxidation catalyst and a particulate filter collectively from a filter case only by opening the outlet of a filter case and extracting a cartridge shell from an inner shell.

  According to the exhaust emission control device of the present invention described above, various excellent effects as described below can be obtained.

  (I) According to the first to fourth aspects of the present invention, since the oxidation catalyst and the particulate filter can be collectively removed from the filter case together with the cartridge shell, the oxidation catalyst is put together with the particulate filter. It can be washed easily.

  (II) In particular, according to the second and third aspects of the present invention, the clearance between the front part or the rear part of the middle part of the filter case and the front part or the rear part, or the cartridge shell and the front part Alternatively, the air insulation layer can be formed by the clearance between the rear part and it is not necessary to attach a heat insulating material such as glass wool around the outer periphery, so that the diameter of the part can be reduced and the insulation cost can be reduced. Can do.

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

  FIG. 1 shows an example of an embodiment for carrying out the present invention, and the same reference numerals as those in FIG. 5 denote the same components.

  In the first embodiment of the present invention shown in FIG. 1, the filter case 7 forming the outer cylinder of the muffler 5 is divided into a front part 12, an intermediate part 13 and a rear part 14 as in the case of FIG. In this case, a structure is adopted in which the bolts 15 and nuts 16 are detachably fastened to each other via flanges 12a, 13a, and 14a, but the intermediate portion 13 extends further forward than the flange 13a. 12, the oxidation catalyst 17 arranged in series in front of the particulate filter 6 is integrally held via an end plate 18, a cushion material 19, and the like.

  That is, in the first embodiment shown in FIG. 1, the cartridge shell that integrally holds the oxidation catalyst 17 and the particulate filter 6 is constituted by the intermediate portion 13 itself.

  On the other hand, the front portion 12 of the filter case 7 is expanded in diameter so as to have an inner diameter larger than the outer diameter of the intermediate portion 13, and the front portion 12 and the intermediate portion 13 are bolted 15 via flanges 12a and 13a. And when fastened with the nut 16, the portion extending forward from the flange 13 a of the intermediate portion 13 is inserted into the front portion 12 via the required clearance C.

  Thus, if the exhaust gas purification apparatus is configured in this way, the oxidation catalyst 17 and the particulate filter 6 can be combined together by simply disconnecting the front part 12, the intermediate part 13 and the rear part 14 of the filter case 7. It becomes possible to remove the intermediate part 13 from the filter case 7, and it becomes possible to easily clean the intermediate part 13 using a dedicated automatic cleaning device or the like, and to this kind of dedicated automatic cleaning device. Mounting can be performed for the entire intermediate portion 13 and the handling becomes easy.

  In addition, when the front portion 12, the intermediate portion 13, and the rear portion 14 are connected to each other, the portion extending forward from the flange 13a of the intermediate portion 13 is inserted into the front portion 12 via the required clearance C. Therefore, an air heat insulating layer is formed by this clearance C, and it is not necessary to attach a heat insulating material such as glass wool around the outer periphery thereof.

  Therefore, according to the above embodiment, the oxidation catalyst 17 and the particulate filter 6 can be collectively removed from the filter case 7 together with the intermediate portion 13, so that the oxidation catalyst 17 can be easily washed together with the particulate filter 6. In addition, the air insulation layer can be formed by the clearance C between the front portion 12 and the portion extending forward from the flange 13a of the intermediate portion 13 of the filter case 7, so that glass wool or the like is formed on the outer periphery thereof. Therefore, it is possible to reduce the diameter of the part and reduce the heat insulation cost.

  FIG. 2 shows a second embodiment of the present invention. In this second embodiment, the filter case 7 constituting the outer cylinder of the muffler 5 is divided into two parts, a front part 12 and a rear part 14. 1 is adopted so as to be detachably fastened by bolts 15 and nuts 16 via flanges 12a and 14a. In the case of the example shown here, the front part 12 of FIG. Thus, the intermediate portion 13 is eliminated.

  The oxidation catalyst 17 and the particulate filter 6 are integrally held by the cartridge shell 22, and the entire cartridge shell 22 is mounted in a state where it is inserted into the front portion 12 via the required clearance C. It has come to be.

  That is, a flange 22a is provided at the rear end of the cartridge shell 22, and the flanges 12a and 14a of the front portion 12 and the rear portion 14 are fastened together by bolts 15 and nuts 16 with the flange 22a interposed therebetween. The mounting state of the cartridge shell 22 is fixed.

  Thus, if the exhaust gas purification apparatus is configured in this way, the connection between the front portion 12 and the rear portion 14 of the filter case 7 is released, and the cartridge shell 22 is simply extracted from the front portion 12 or the rear portion 14. 17 and the particulate filter 6 can be removed from the filter case 7 together, and the cartridge shell 22 as a whole is connected to the front part 12 or the rear part 14 via the required clearance C in the mutually connected state. Since it is in the inserted state, an air heat insulation layer is formed by this clearance C, and it is not necessary to install a heat insulating material such as glass wool around the outer periphery, so that the diameter of the part is reduced and the heat insulation cost is reduced. Can be achieved.

  FIG. 3 shows a third embodiment of the present invention. In this third embodiment, the muffler 5 formed in a box shape is targeted, and the casing of the muffler 5 is A filter case 7 is formed.

  In the example shown here, the inside of the filter case 7 is divided into a first chamber 25, a second chamber 26, and a third chamber 27 by separators 23 and 24, and from the second chamber 26 to the third chamber. 27, a cylindrical inner shell 30 is fixedly installed through the separator 24, and the cartridge shell 22 formed by integrally holding the oxidation catalyst 17 and the particulate filter 6 in the inner shell 30 is a filter case. 7 is inserted and mounted from the rear side.

  That is, an outlet 28 is provided on the rear surface side of the filter case 7 so that the cartridge shell 22 can be inserted / removed from / to the inner shell 30 by the lid 29 so that the cartridge shell 22 can be opened and closed. After being inserted and housed, the flange 22a at the rear end of the cartridge shell 22 is fastened together with the outer edge portion of the lid 29 together with the bolt 15 and the nut 16 to the rear surface of the filter case 7. The mounting state of the cartridge shell 22 is fixed by this tightening.

  In addition, an inlet pipe 8 for introducing the exhaust gas 3 from the upstream exhaust pipe 4 (see FIG. 4) is inserted from the front surface of the filter case 7 of the muffler 5 to the first separator 23 to close the tip. The exhaust gas 3 introduced by the inlet pipe 8 is discharged to the first chamber 25 through the air diffusion hole 8a.

  The exhaust gas 3 released into the first chamber 25 is introduced from the front end of the cartridge shell 22 into the oxidation catalyst 17, and the exhaust gas 3 that has passed through the oxidation catalyst 17 flows into the particulate filter 6 and flows into the particulate filter 6. After being collected, the slit 31 on the rear end side of the cartridge shell 22 and the slit 32 on the rear end side of the inner shell 30 are discharged into the third chamber 27 through the respective.

  Here, an outlet pipe 9 for discharging the exhaust gas 3 purified by the particulate filter 6 is inserted in parallel with the inlet pipe 8 from the front surface of the filter case 7 of the muffler 5 to the third chamber 27 to open the tip. Therefore, the exhaust gas 3 discharged into the third chamber 27 is extracted to a downstream exhaust pipe (not shown) through the outlet pipe 9.

  Even in the case where the present invention is applied to the box-shaped muffler 5 as described above, it is possible to remove the lid 29 and open the outlet 28 to extract the cartridge shell 22 from the inner shell 30. The curative filter 6 can be removed together from the filter case 7, and the oxidation catalyst 17 can be easily washed together with the particulate filter 6.

  The exhaust emission control device of the present invention is not limited to the above-described embodiment, and does not necessarily have to have a muffler function as a muffler. Other than that, it does not depart from the gist of the present invention. Of course, various changes can be made.

It is sectional drawing which shows the 1st example of a form of this invention. It is sectional drawing which shows the 2nd example of a form of this invention. It is sectional drawing which shows the 3rd example of a form of this invention. It is the schematic which shows a prior art example. It is sectional drawing which shows the detail of the internal structure of the muffler of FIG.

Explanation of symbols

3 exhaust gas 4 exhaust pipe 5 muffler 6 particulate filter 7 filter case 12 front part 12a flange 13 intermediate part 13a flange 14 rear part 14a flange 15 bolt 16 nut 17 oxidation catalyst 21 heat insulating material 22 cartridge shell 22a flange 28 outlet 29 lid 30 Inner Shell C Clearance

Claims (4)

  An exhaust gas purification apparatus that allows particulates in the exhaust gas to be removed by passing the exhaust gas through a particulate filter installed in the filter case in the middle of the exhaust pipe, wherein an oxidation catalyst is arranged in series in front of the particulate filter. An exhaust gas purification apparatus comprising the oxidation catalyst and the particulate filter integrally held by a cartridge shell, the cartridge shell being detachable from the filter case.   The filter case is divided into a front part, an intermediate part and a rear part so that they can be connected to each other, and the intermediate part itself is used as a cartridge shell, and one of the front and rear parts is required at the front part or the rear part. The exhaust purification device according to claim 1, wherein the intermediate portion and the front portion or the rear portion are connected in a state of being inserted through a clearance.   The filter case is divided into a front part and a rear part so that they can be connected to each other, and the entire cartridge shell is attached to the front part or the rear part through a required clearance, and the attached state is The exhaust emission control device according to claim 1, wherein the exhaust purification device is configured to be fixed by connecting the front portion and the rear portion.   An inner shell into which the cartridge shell can be inserted and mounted is fixedly installed in the filter case, and an outlet is provided at an appropriate position of the filter case so that the cartridge shell can be inserted into and removed from the outer shell. 2. The exhaust emission control device according to claim 1, wherein a mounting state of the cartridge shell mounted on the shell is fixed by closing the outlet.

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