JP2018009505A - Exhaust emission control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily secure the clearance required to between the frame bottom edges while securing the ground height required by a flange at the division position of a muffler having an after treatment device such as a particulate filter accommodated in the interior.SOLUTION: With an exhaust emission control device, in which a muffler 3 in the middle of an exhaust pipe is divided and detachably fastened via a flange 6, and a particulate filter 1 (after treatment device) is accommodated inside the muffler 3 for purifying exhaust gas, the flange 6 is formed into a nine-sided shape having fastening portions 7a to 7i at the nine circumferential positions as apexes; three fastening portions 7a, 7b, and 7c are arranged in a triangular shape so that at least the top portion of the flange 6 forms a mountain shape; and two fastening portions 7d and 7e are arranged horizontally so that the bottom forms a horizontal end.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an exhaust emission control device.

  Particulate matter (particulate matter) discharged from a diesel engine is mainly composed of a soot fraction composed of carbon and a SOF fraction (Soluble Organic Fraction) composed of a high-boiling hydrocarbon component. In addition, it has a composition containing a small amount of sulfate (mist-like sulfuric acid component). As a measure to reduce this type of particulates, a particulate filter is accommodated in a muffler in the middle of the exhaust pipe. It has been done conventionally.

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

  As shown in FIG. 4, when mounting such a particulate filter 1 on a vehicle, the muffler 3 in the middle of the exhaust pipe 2 is housed in the muffler 3 so that the muffler 3 and the exhaust pipe 2 are suspended and supported at the lower part of the frame 4. In order to prevent the muffler 3 from projecting to the outside of the frame 4, a mounting space for various equipment such as a fuel tank is secured outside the frame 4.

  Here, the particulates collected on the inner surface of the porous thin wall in the particulate filter 1 are removed by self-combustion in the operating region where the exhaust gas temperature is high, or in the previous stage of the particulate filter 1. The fuel added in the post-injection or the like on the engine side is introduced into the oxidation catalyst 5 to cause an oxidation reaction, so that the exhaust temperature is forcibly raised and removed by combustion.

  However, since the ash generated by in-cylinder combustion due to the lubricating oil gradually accumulates in the particulate filter 1, the particulate filter 1 is periodically taken out and cleaned by air washing or water washing. It is necessary to replace the particulate filter 1 with a new one, and the particulate filter 1 can be appropriately taken out by dividing the muffler 3 and detachably fastening the muffler 3 via the flange 6. is there.

  As prior art document information related to this type of exhaust purification device, there is the following Patent Document 1 and the like.

JP-A-2005-76559

  However, the conventional flange 6 of the muffler 3 employs a regular octagonal flange 6 having apexes 8 fastening points 7a to 7h in the circumferential direction as shown in FIG. 5 so that the surface pressure at the time of fastening can be easily stabilized. Therefore, when trying to secure the necessary ground height H with the road surface G, the muffler 3 is attached in such a posture that the bottom portion forms a horizontal end so that the bottom portion of the flange 6 does not protrude downward as much as possible. If this is done, the top of the flange 6 also forms a horizontal end, which easily interferes with the lower end of the frame 4, making it difficult to secure the necessary clearance C between the lower end of the frame 4 and driving on a rough road. There is a problem that the frame 4 and the muffler 3 are likely to collide with each other due to relative displacement.

  In Patent Document 1 mentioned above, a structure is proposed in which the diameter of the vicinity of the muffler division position is reduced to form a throttle portion, and the flange is prevented from protruding as much as possible by this throttle portion. However, the formation of such a narrowed part leads to an increase in the length of the muffler, so there are many cases that cannot be adopted due to layout restrictions with surrounding structures, and proposals for new countermeasures in such cases are required. It has been.

  The present invention has been made in view of the above-described circumstances, and a flange at a division position of a muffler in which a post-processing device such as a particulate filter is housed is necessary between the lower end of the frame while ensuring a necessary ground height. It is an object to make it easy to secure a clear clearance.

  According to the present invention, an exhaust purification aftertreatment device is accommodated inside a muffler in the middle of an exhaust pipe that is suspended and supported at the lower part of the frame, and the muffler is divided so that the aftertreatment device can be taken out appropriately. An exhaust emission control device detachably fastened via a flange, wherein the flange is formed in a polygonal shape having a plurality of fastening points in the circumferential direction as apexes, and at least the top of the flange forms a chevron. The two fastening points are horizontally arranged so that one fastening point is arranged in a triangular shape and the bottom part forms a horizontal end.

  Thus, in this way, since the two fastening points are horizontally arranged so that the bottom of the flange forms a horizontal end, it is possible to minimize the downward protrusion of the bottom of the flange. It is possible to secure the necessary ground clearance between the bottom of the flange and the road surface, while the three fastening points are arranged in a triangular shape so that the top of the flange forms a chevron. It is possible to easily avoid interference with the lower end of the frame at the oblique side portion of the angle while allowing the peak portion of the angled shape to escape to the inside of the lower end of the frame and project to a position higher than the lower end of the frame. It is easy to secure a necessary clearance between the lower end of the frame.

  Further, in concrete implementation of the present invention, the flange may be formed so as to form at least a heptagonal odd-numbered square, and more preferably, the flange is any of a heptagon, a hexagon, and an eleven. It is good that it is formed to form.

  That is, when the three fastening points are arranged in a triangle shape so that the top of the flange forms a chevron and the two fastening points are arranged horizontally so that the bottom forms a horizontal end, The merit that the arrangement | positioning of a fastening place with a symmetrical balance is attained is attained.

  However, in the pentagon, there are too few fastening points, which causes a demerit that it is difficult to apply the surface pressure between the fastening points, and conversely, even in the case of a 13-sided or more, the fastening portion in the middle portion excluding the top and bottom portions There is no merit just because the interval of is just wasted.

  According to the above-described exhaust purification apparatus of the present invention, the clearance at the lower end of the frame is ensured while the flange at the division position of the muffler in which the after-treatment device such as the particulate filter is accommodated ensures a necessary ground clearance. It is easy to ensure, and the possibility that the frame and the muffler may collide with each other due to relative displacement when traveling on a rough road or the like is greatly reduced, and the excellent effect that the muffler can be protected more reliably than before can be achieved.

It is sectional drawing which shows an example of the form which implements this invention. It is sectional drawing at the time of making the flange of FIG. 1 into a heptagon. It is sectional drawing at the time of making the flange of FIG. It is a side view which shows an example of the conventional exhaust gas purification apparatus. It is sectional drawing of the VV arrow of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an example of an embodiment of the present invention, and is a cross-sectional view corresponding to the VV arrow of FIG. 4 used for explaining a conventional example. Here, since the side view of the entire structure of the present embodiment is substantially the same as that of FIG. 4, the following description will refer to FIG. 4 as equivalent to the side view of the present embodiment.

  The exhaust purification apparatus of this embodiment is similar to the conventional exhaust purification apparatus described with reference to FIG. 4 described above, and the inside of the muffler 3 in the middle of the exhaust pipe 2 (see FIG. 4) suspended and supported at the lower part of the frame 4. A particulate filter 1 for exhaust gas purification is housed, and the muffler 3 is divided so that the particulate filter 1 can be taken out appropriately, and the muffler 3 is detachably fastened via a flange 6. The flange 6 is formed in a nine-sided shape having nine fastening points 7a to 7i in the circumferential direction as apexes, and the three fastening points 7a, 7b and 7c are triangular so that the top of the flange 6 forms a chevron. The two fastening points 7d and 7e are arranged horizontally such that the bottom part forms a horizontal end.

  Thus, in this way, since the two fastening points 7d and 7e are horizontally arranged so that the bottom of the flange 6 forms a horizontal end, the protrusion of the bottom of the flange 6 to the bottom is minimized. It is easy to secure the necessary ground height H between the bottom of the flange 6 and the road surface G, while the three fastening points 7a, 7b, 7c are formed so that the top of the flange 6 forms a chevron. Are arranged in a triangular shape, so that the peak portion of the mountain shape at the top portion of the flange 6 escapes to the inside of the lower end of the frame 4 and protrudes to a position higher than the lower end of the frame 4. Interference with the lower end can be avoided without difficulty, and a necessary clearance C is easily secured between the top of the flange 6 and the lower end of the frame 4.

  Therefore, according to the above-described embodiment, the flange 6 at the division position of the muffler 3 in which the particulate filter 1 such as the particulate filter 1 is accommodated is secured between the lower end of the frame 4 while ensuring the necessary ground height H. It becomes easy to secure the necessary clearance C, and the possibility that the frame 4 and the muffler 3 collide with each other due to relative displacement when traveling on a rough road or the like can be greatly reduced, so that the muffler 3 can be protected more reliably than before.

  In the above description, the case where the flange 6 is a hexagon is described. However, it is preferable that the flange 6 is formed so as to form at least an octagon or more, and more preferably, the flange 6 is a heptagon. It is good to form so that either a 9-sided shape or an 11-sided shape may be formed.

  That is, when the three fastening points 7a, 7b, 7c are arranged in a triangular shape so that the top of the flange 6 forms a chevron, and the two fastening points 7d, 7e are arranged horizontally so that the bottom forms a horizontal end, By making the flange 6 odd-numbered, the merit that it is possible to arrange the fastening points 7a to 7i that are balanced in a symmetrical manner is obtained.

  However, in the pentagon, there are too few fastening points, which causes a demerit that it is difficult to apply the surface pressure between the fastening points, and conversely, even in the case of a 13-sided or more, the fastening portion in the middle portion excluding the top and bottom portions There is no merit just because the interval of is just wasted.

  For example, as shown in FIG. 2, the flange 6 is formed into a heptagon having seven fastening points 7a to 7g in the circumferential direction as apexes, or as shown in FIG. 3, the flange 6 is fastened to 11 places in the circumferential direction. Even if it is formed in an 11-sided shape having the apexes 7a to 7k, the three fastening points 7a, 7b, 7c are arranged in a triangular shape so that the top of the flange 6 forms a mountain shape, and the bottom portion forms a horizontal end. If the two fastening points 7d and 7e are arranged horizontally, the same operational effects as those of the above-described nine-sided flange 6 in FIG. 1 can be obtained.

  The exhaust purification device of the present invention is not limited to the above-described embodiment. In the illustrated example, the post-processing device is a particulate filter, but various types for purifying exhaust gas are shown. Of course, it may be a catalyst, and various changes can be made without departing from the scope of the present invention.

1 Particulate filter (post-processing device)
2 Exhaust pipe 3 Muffler 6 Flange 7a Fastening location 7b Fastening location 7c Fastening location 7d Fastening location 7e Fastening location 7f Fastening location 7g Fastening location 7h Fastening location 7i Fastening location 7j Fastening location 7k Fastening location

Claims (3)

  An exhaust purification device that divides a muffler in the middle of an exhaust pipe and detachably fastens it between each other via a flange and accommodates an aftertreatment device for purifying exhaust gas inside the muffler, wherein the flange It is formed in a polygonal shape with a plurality of fastening locations in the direction as apexes, and at least three fastening locations are arranged in a triangular shape so that the top of the flange forms a chevron and the bottom forms a horizontal end. An exhaust emission control device characterized in that two fastening points are arranged horizontally.   The exhaust emission control device according to claim 1, wherein the flange is formed so as to form an odd-numbered square of at least a heptagon.   The exhaust emission control device according to claim 1 or 2, wherein the flange is formed so as to form one of a heptagon, a nine-sided shape, and an eleven-sided shape.

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