JP4833944B2 - Exhaust purification device - Google Patents

Description

  The present invention relates to an exhaust purification device.

  In recent years, a filter that collects particulates contained in exhaust gas has been incorporated into the engine exhaust system, and the NOx can be selectively reacted with ammonia even in the presence of oxygen at the downstream side of the filter of the same engine exhaust system. It has been proposed that a catalyst is provided and urea water for reduction is added between the filter and the selective catalytic reduction catalyst to collect particulates and reduce NOx.

  When taking such measures, if the urea water added to the exhaust gas is to be sufficiently decomposed into ammonia and carbon dioxide, the distance from the urea water addition position to the selective catalytic reduction catalyst is increased. Although it must be long, if the filter for collecting particulates and the selective reduction catalyst are arranged coaxially apart from each other, the mountability on the vehicle will be significantly impaired.

  Therefore, as shown in FIG. 4 as Japanese Patent Application No. 2007-29923, the applicant of the present invention has an excellent exhaustibility in a vehicle and can increase the distance from the urea water addition position to the selective catalytic reduction catalyst. A purification device has already been proposed.

  In this exhaust purification apparatus, a casing 7 containing a filter 5 for collecting particulates and a casing 8 containing a selective catalytic reduction catalyst 6 for reducing NOx are arranged in parallel with each other. The exhaust pipe 4 connected to the exhaust manifold 2 of the diesel engine 1 is connected to the exhaust inlet side end of the casing 7, and the exhaust outlet side end of the casing 7 and the casing 8. The exhaust inlet side end is connected by a communication flow path 9.

  The casing 7 including the filter 5 extends in the vehicle (truck) front-rear direction and is disposed near the side surface of the side member of the frame. The casing 8 including the selective catalytic reduction catalyst 6 extends in the vehicle front-rear direction. It is arrange | positioned in the vehicle bed bottom side so that it may be located in the vehicle width direction outer side.

  The communication flow path 9 surrounds the exhaust outlet side end of the casing 7 and collects and guides the exhaust 3 that has passed through the filter 5 upward, and the exhaust 3 that has passed through the collective chamber 9A flows into the casing 7. The mixing pipe 9B that leads to the vicinity of the exhaust inlet side end of the casing 8 and the exhaust 3 that surrounds the exhaust inlet side of the casing 8 and that passes through the mixing pipe 9B are laterally scattered and guided in the opposite direction. And a dispersion chamber 9C leading to the selective catalytic reduction catalyst 6.

  Further, urea water addition means 10 for the exhaust 3 is provided at a position near the collecting chamber 9A of the mixing pipe 9B.

  In this exhaust purification device, casings 7 and 8 in which exhaust 3 flows along the vehicle longitudinal direction are arranged in the vehicle width direction in each interior, and mixing pipe 9B is positioned above casing 8 so that the entire device in the vehicle longitudinal direction is arranged. Since the size and the size in the vehicle width direction are not excessive, it is easy to mount on the vehicle, and the distance from the urea water addition means 10 to the selective catalytic reduction catalyst 6 is increased and added to the exhaust 3. Sufficient time can be ensured for the urea water to be thermally decomposed into ammonia and carbon dioxide.

  Further, an oxidation catalyst 11 for treating unburned fuel contained in the exhaust 3 is provided in the front stage in the casing 7, and surplus ammonia is oxidized in the rear stage in the casing 8. An ammonia reduction catalyst 12 is provided.

  The oxidation catalyst 11 uses a monolithic catalyst carrier that allows the exhaust 3 to flow through a large number of flow paths arranged in parallel.

  The filter 5 has a structure in which a honeycomb core is formed of ceramics such as cordierite, and the exhaust 3 is circulated through a large number of channels divided by the porous thin wall of the honeycomb core. The particulates contained in are collected.

  In order to prevent the exhaust resistance of the filter 5 from increasing, the particulates deposited on the porous thin wall are subjected to combustion treatment to regenerate the filter 5. However, when the diesel engine 1 is normally operated, the particulates are There is little opportunity for the temperature of the exhaust 3 to rise to such an extent that spontaneous ignition can occur.

  Therefore, the fuel is added to the exhaust 3 before entering the casing 7, and the temperature of the exhaust 3 is raised by the heat generated when the fuel reacts with the oxidation catalyst 11, thereby promoting the particulate combustion process. However, the ash derived from the lubricating oil generated by the combustion in the cylinder of the diesel engine 1 gradually accumulates in the filter 5.

  For this reason, it is necessary to wash the filter 5 with high-pressure hot water or the like, and as shown in FIG. 3, the collecting chamber 9 </ b> A can be removed from the exhaust outlet side end of the casing 7.

  The casing 7 containing the filter 5 extends in the longitudinal direction of the vehicle (truck), has a small-diameter flow port 13 at the downstream end in the exhaust flow direction, and a connection flange 14 is provided at the tip of the flow port 13. is there.

  The collective chamber 9A has a main body flow passage portion 15 extending in a direction intersecting with the central axis of the casing 7, and a stand pipe 16 that communicates with the main body flow passage portion 15 and extends toward the casing 7, A connecting flange 17 having the same shape as the connecting flange 14 is provided at the tip of the stand pipe 16.

  The connecting flange 14 on the casing 7 side and the connecting flange 17 on the collecting chamber 9 </ b> A side are abutted via a gasket 18 for preventing leakage of the exhaust 3, and are fastened by bolts 19 and nuts 20.

  A nut 20 is welded to the connecting flange 14 for each bolt hole, and a boss 21 is welded to the connecting flange 17 for each bolt hole.

As an exhaust gas purification apparatus in which a particulate collection filter and a selective reduction catalyst are arranged in parallel, there is one of the following Patent Document 1.
JP 2005-155404 A

  When the exhaust gas purification device of FIG. 3 is viewed from the assembly chamber 9A side to the casing 7 side, the bolt 19 inserted into a position where the main body flow path portion 15 of the connecting flange 17 does not overlap is continuously provided by a T-type box wrench 22 or the like. The T-type box wrench 22 cannot be used for the bolt 19 inserted into the position where the main body flow path portion 15 of the connection flange 17 overlaps, so that the L-type box wrench 23 having a ratchet mechanism is intermittently used. Must be turned around.

  In addition, considering the insertion and removal of the bolt 19 to the position where the main body flow path portion 15 of the connecting flange 17 overlaps, the axial dimension of the stand pipe 16 is set to exceed at least the total length of the bolt 19 (in this example) The thickness of the boss 21 must be estimated), and the axial dimension of the casing 7 of the exhaust gas purification apparatus cannot be reduced.

  An object of the present invention is to provide an exhaust purification device that is excellent in maintainability and can be downsized.

  In order to achieve the above object, the invention according to claim 1 is provided at the tip of the circulation port, including a cylindrical body containing a particulate collection filter and having a small-diameter circulation port at the downstream end in the exhaust circulation direction. And a connecting chamber having first and second side walls facing each other, a bolt for fastening the first side wall to the connecting flange, and a working hole of a size through which the bolt can pass. A socket and a plug that can be attached to and detached from the working hole, and the first side wall of the assembly chamber is provided with an opening communicating with the circulation port of the cylindrical body and a first hole corresponding to the connecting flange; A second hole of a size that allows the bolt to pass through is drilled in the second side wall of the collecting chamber so as to face the first hole, and the socket is aligned with the second hole on the second side wall. After fixing, put bolts into the assembly chamber from the socket work hole, After it has entered into a first sidewall to the connecting flange of the flow port, wearing the plug into the socket.

  In the second aspect of the invention, the inner diameter of the working hole of the socket is set so that the box portion of the wrench that fits the bolt can pass through.

  According to a third aspect of the present invention, the working hole of the socket is a screw hole, and the plug is formed so as to be able to be screwed into the working hole.

  According to a fourth aspect of the present invention, there is provided a cylindrical body including a filter for collecting particulates and having a small-diameter flow port at a downstream end in a direction of exhaust flow, a connection flange provided at a tip of the flow port, A collecting chamber having first and second side walls facing each other, a bolt for fastening the first side wall to a connecting flange, a nipple having a working hole of a size through which the bolt can pass, and a detachable attachment to the nipple A first cap corresponding to the connecting flange and a first hole corresponding to the connecting flange, and the first side wall of the collecting chamber is formed in the second side wall of the collecting chamber. A second hole having a size that allows the bolt to pass through is drilled so as to face the first hole, and the nipple is aligned with the second hole and fixed to the second side wall. Insert bolts into the assembly room, and connect the first side wall After it has entered into in connection flange, wearing the cap on the nipple.

  In the invention described in claim 5, the inner diameter of the working hole of the nipple is set so that the box portion of the wrench that fits the bolt can pass through.

  According to a sixth aspect of the present invention, the outer peripheral surface of the nipple is a male screw, and the cap is formed so as to be screwable with the nipple.

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

  (1) In the state where the plug is not attached to the socket, the bolt can be inserted into the inside of the collecting chamber through the socket working hole and continuously rotated, so the collecting chamber is removed from the exhaust outlet side end of the cylinder. The work or the work of attaching the collecting chamber to the exhaust outlet side end of the cylinder can be performed efficiently, and the maintainability of the exhaust gas purification device is improved.

  (2) In a state where the cap is not attached to the nipple, the bolt can be inserted into the collecting chamber through the working hole of the nipple and continuously rotated, so the collecting chamber is removed from the exhaust outlet side end of the cylinder. The work or the work of attaching the collecting chamber to the exhaust outlet side end of the cylinder can be performed efficiently, and the maintainability of the exhaust gas purification device is improved.

  (3) Since the bolt for fastening the connecting flange on the cylinder side and the first side wall of the collective chamber is inserted into the collective chamber, the outer shell of the collective chamber does not interfere with the bolt when inserting and removing the bolt. Further, a portion for extending the axial dimension of the casing becomes unnecessary, and the exhaust purification device can be downsized.

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

  FIG. 1 is a first example of an exhaust emission control device according to the present invention. In the figure, the same reference numerals as those in FIGS. 3 and 4 denote the same components.

  This exhaust purification device has a structure in which the collecting chamber 24 can be removed from the exhaust outlet side end of the casing 7 in order to clean the particulate collection filter 5 with high-pressure hot water or the like.

  The casing 7 containing the filter 5 extends in the longitudinal direction of the vehicle (truck), has a small-diameter flow port 13 at the downstream end in the exhaust flow direction, and a connection flange 14 is provided at the tip of the flow port 13. is there.

  The collecting chamber 24 is connected to the main body flow path portion 25 extending in a direction intersecting with the central axis of the casing 7, and is connected to the main body flow path portion 25 and is opposed to the connection flange 14 of the circulation port 13 on the casing 7 side. Chamber 26.

  Downstream of the collecting chamber 24 in the exhaust flow direction, there is a mixing pipe provided with urea water addition means, and a dispersion chamber for dispersing the exhaust 3 that has passed through the mixing pipe to reach a selective catalytic reduction catalyst in another casing. It is lined up.

  The chamber 26 has a flat outer shape having first and second side walls 27, 28 facing each other, and the first side wall 27 is fastened to the connecting flange 14 by a bolt 19 and a nut 20, and is attached to the second side wall 28. A socket 30 having a working hole 29 of a size that allows the bolt fitting portion of the bolt 19 and the T-type box wrench 22 to pass through is attached. The working hole 29 is a screw hole into which the plug 31 can be screwed. It has become.

  The collecting chamber 24 includes a press-molded product that forms approximately half of the main body flow passage portion 25 and the first side wall 27, and another press-formed product that forms the remaining half of the main body flow passage portion 25 and the second side wall 28. Are joined.

  The first side wall 27 has an opening 32 communicating with the flow port 13 and a plurality of first holes 33 corresponding to the respective bolt holes of the connection flange 14 of the flow port 13. The second side wall 28 is formed with a second hole 34 so as to face the first hole 33, and the socket 30 is fitted in the second hole 34 and the second side wall 28 is inserted into the second side wall 28. It is welded to 28.

  The connecting flange 14 on the casing 7 side and the first side wall 27 of the chamber 26 are abutted via a gasket 18 and fastened by a bolt 19 and a nut 20.

  A nut 20 is welded to the connecting flange 14 for each bolt hole, and a boss 35 is welded to the inner surface of the first side wall 27 for each first hole 33.

  When the plug 31 is screwed into the working hole 29 (see the lower side in FIG. 1), a gasket 36 externally fitted to the shaft portion of the plug 31 is connected to the head of the plug 31 and the outside of the chamber 26 of the socket 30. It is sandwiched between the end faces.

  In this exhaust purification device, when the plug 31 is not screwed into the socket 30 (see the upper side in FIG. 1), the bolt fitting portion of the T-type box wrench 22 is connected from the working hole 29 of the socket 30 to the collecting chamber 24. Any bolt 19 can be continuously turned into the interior of the chamber 26.

  That is, when the filter 5 is washed, the work of removing the collecting chamber 24 from the exhaust outlet side end of the casing 7 or the operation of attaching the collecting chamber 24 to the exhaust outlet side end of the casing 7 can be efficiently performed. The maintainability of the purification device is increased.

  Further, since the bolt 19 for fastening the connecting flange 14 on the casing 7 side and the first side wall 27 on the collecting chamber 24 side is inserted into the chamber 26, when the bolt 19 is inserted or removed, the main body flow passage portion of the collecting chamber 24 is inserted. 25 does not interfere.

  This eliminates the need to extend the axial dimension of the casing 7 such as the stand pipe 16 in FIG. 3, and the exhaust purification device can be downsized by this amount.

  FIG. 2 shows a second example of the exhaust emission control device according to the present invention. In the figure, the same reference numerals as those in FIGS. 1, 3, and 4 denote the same components.

  This exhaust purification apparatus has a structure in which the collecting chamber 24 can be removed from the exhaust outlet side end of the casing 7 in order to wash the particulate collection filter 5 with high-pressure hot water or the like. 25 and the chamber 26.

    The chamber 26 has a flat outer shape having first and second side walls 27, 28 facing each other, and the first side wall 27 is fastened to the connecting flange 14 by a bolt 19 and a nut 20, and is attached to the second side wall 28. , A nipple 38 having a working hole 37 of a size through which a bolt fitting portion of the bolt 19 and the T-type box wrench 22 can pass, and a male screw to which a cap 39 can be screwed on an outer peripheral surface of the nipple 38. It has become.

  The collecting chamber 24 includes a press-molded product that forms approximately half of the main body flow passage portion 25 and the first side wall 27, and another press-formed product that forms the remaining half of the main body flow passage portion 25 and the second side wall 28. Are joined.

  The first side wall 27 has an opening 32 communicating with the flow port 13 and a plurality of first holes 33 corresponding to the respective bolt holes of the connection flange 14 of the flow port 13. A second hole 34 is formed in the second side wall 28 so as to face the first hole 33, and the proximal end portion socket 30 of the nipple 38 is fitted in the second hole 34. And welded to the second side wall 28.

  The connecting flange 14 on the casing 7 side and the first side wall 27 of the chamber 26 are abutted via a gasket 18 and fastened by a bolt 19 and a nut 20.

  A nut 20 is welded to the connecting flange 14 for each bolt hole, and a boss 35 is welded to the inner surface of the first side wall 27 for each first hole 33.

  When the cap 39 is screwed into the nipple 38 (see the lower side in FIG. 2), the gasket 40 fitted in the recess of the cap 39 is sandwiched between the cap 39 and the tip surface of the nipple 38.

  In this exhaust purification device, when the cap 39 is not screwed into the nipple 38 (see the upper side in FIG. 2), the bolt fitting portion of the T-type box wrench 22 is connected to the collecting chamber 24 from the work hole 37 of the nipple 38. Any bolt 19 can be continuously turned into the interior of the chamber 26.

  That is, when the filter 5 is washed, the work of removing the collecting chamber 24 from the exhaust outlet side end of the casing 7 or the operation of attaching the collecting chamber 24 to the exhaust outlet side end of the casing 7 can be efficiently performed. The maintainability of the purification device is increased.

  Further, since the bolt 19 for fastening the connecting flange 14 on the casing 7 side and the first side wall 27 on the collecting chamber 24 side is inserted into the chamber 26, when the bolt 19 is inserted or removed, the main body flow passage portion of the collecting chamber 24 is inserted. 25 does not interfere.

  This eliminates the need to extend the axial dimension of the casing 7 such as the stand pipe 16 in FIG. 3, and the exhaust purification device can be downsized by this amount.

  It should be noted that the exhaust emission control device of the present invention is not limited to the above-described embodiment, and it is needless to say that changes can be made without departing from the gist of the present invention.

  The exhaust emission control device of the present invention can be applied to various vehicle types.

It is a partial longitudinal cross-sectional view which shows the 1st example of the exhaust gas purification apparatus of this invention. It is a conceptual diagram of the internal combustion engine equipped with the 2nd example of the exhaust gas purification apparatus of this invention. It is a fragmentary longitudinal cross-section which shows an example of the conventional exhaust gas purification apparatus. It is a conceptual diagram of the internal combustion engine equipped with an example of the conventional exhaust emission control device.

Explanation of symbols

5 Filter 7 Casing (cylinder)
DESCRIPTION OF SYMBOLS 13 Distribution port 14 Connection flange 19 Bolt 22 T-type box wrench 24 Collecting chamber 27 1st side wall 28 2nd side wall 29 Working hole 30 Socket 31 Plug 32 Opening 33 1st hole 34 2nd hole 37 Working hole 38 Nipple 37 cap

Claims (6)

  A cylindrical body containing a particulate collection filter and having a small-diameter flow port at the downstream end in the exhaust flow direction, a connection flange provided at the tip of the flow port, and first and second side walls facing each other A collecting chamber, a bolt for fastening the first side wall to the connecting flange, a socket having a working hole of a size through which the bolt can pass, and a plug removable from the working hole, The first side wall of the chamber is formed with an opening communicating with the circulation port of the cylinder and a first hole corresponding to the connecting flange, and the bolt can pass through the second side wall of the collecting chamber. The second hole is drilled so as to face the first hole, the socket is fixed to the second side wall in alignment with the second hole, a bolt is inserted into the assembly chamber from the working hole of the socket, After fastening the first side wall to the connection flange of the distribution port, Exhaust gas purification apparatus characterized by mounting the plug to the socket.   The exhaust emission control device according to claim 1, wherein an inner diameter of the working hole of the socket is set so that a box portion of a wrench that fits the bolt can pass through.   The exhaust purification device according to claim 1 or 2, wherein the socket has a working hole as a screw hole, and the plug is formed to be screwable into the working hole.   A cylindrical body containing a particulate collection filter and having a small-diameter flow port at the downstream end in the exhaust flow direction, a connection flange provided at the tip of the flow port, and first and second side walls facing each other A collecting chamber, a bolt for fastening the first side wall to the connecting flange, a nipple having a work hole of a size through which the bolt can pass, and a cap removable from the nipple. The first side wall of the cylindrical body has an opening communicating with the circulation port of the cylindrical body and a first hole corresponding to the connecting flange, and the bolt can pass through the second side wall of the collecting chamber. The second hole is drilled so as to face the first hole, the nipple is aligned with the second hole and fixed to the second side wall, a bolt is inserted into the assembly chamber from the work hole of the nipple, 1 side wall was fastened to the connection flange of the distribution port An exhaust gas purification apparatus characterized by mounting the cap on the nipple.   The exhaust emission control device according to claim 1, wherein an inner diameter of the work hole of the nipple is set so that a box portion of a wrench that fits the bolt can pass through.   6. The exhaust emission control device according to claim 4, wherein the outer peripheral surface of the nipple is a male screw and the cap is formed so as to be screwable with the nipple.

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