JP2008106665A - Exhaust emission control device in internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce deterioration of a catalyst by a moisture content contained in an exhaust gas in an exhaust emission control device which is constituted such that a cleaning case 1 built-in with any one or both of a particulate filter catalyst 16 and an oxidation catalyst is provided with an exhaust gas inlet 5 to the catalyst and an exhaust gas outlet 8 from the catalyst. <P>SOLUTION: A drain storage part 6 is provided between the catalyst 16 and the exhaust gas outlet 8 of the cleaning case 1 so as to store the drain in a downstream side of the catalyst. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus for purifying exhaust gas in an internal combustion engine such as a diesel engine.

In general, any one of a particulate filter and an oxidation catalyst is used to purify exhaust gas in an internal combustion engine such as a diesel engine. Patent Document 1 as a prior art describes the particulate filter catalyst and / or Alternatively, an exhaust gas purification device is described in which an exhaust gas inlet to the catalyst and an exhaust gas outlet from the catalyst are provided in a purification case incorporating an oxidation catalyst.
JP 2005-16374 A

  However, in this prior art exhaust gas purification device, the exhaust gas purified by passing through the particulate filter catalyst and / or the oxidation catalyst is directly discharged from the exhaust gas outlet. In the exhaust gas purified by passing through the curative filter catalyst and / or the oxidation catalyst, water drops are generated when the temperature is lower than the inlet side to the particulate filter catalyst and / or the oxidation catalyst. In addition to the collection of water droplets and drainage, when the operation of the internal combustion engine is stopped, water droplets that condense on the inner surface etc. on the downstream side of the particulate filter catalyst and / or the oxidation catalyst collect and collect in the drain. These drains flow into the particulate filter catalyst and / or oxidation catalyst side (reverse ) Will be.

  Then, the water drain flowing into the particulate filter catalyst and / or the oxidation catalyst evaporates and partially cools the particulate filter catalyst and / or the oxidation catalyst. There has been a problem in that deterioration such as cracks in the catalyst is promoted.

  It is a technical object of the present invention to provide an exhaust gas purification device that solves these problems.

In order to achieve this technical problem, claim 1 of the present invention provides:
“In an exhaust gas purification apparatus comprising an exhaust gas inlet to the catalyst and an exhaust gas outlet from the catalyst in a purification case containing either one or both of a particulate filter catalyst and an oxidation catalyst,
A drain reservoir portion is provided between the catalyst and the exhaust gas outlet in the purification case so as to collect drain on the downstream side of the catalyst. "
. "
It is characterized by that.

Further, claim 2 of the present invention is
“In the first aspect of the present invention, the drain reservoir is provided with drainage means at the bottom thereof.”
It is characterized by that.

Claim 3 of the present invention provides:
“In claim 2 of the present invention, the purifying case is provided with guide means for guiding the drain to the drain reservoir.”
It is characterized by that.

Claim 4 of the present invention provides:
“In the claim 2 or 3, the draining means is a solenoid valve.”
It is characterized by that.

Claim 5 of the present invention provides:
“In any one of claims 1 to 4, the catalyst is built in a filter case that is removably inserted into the purification case.”
It is characterized by that.

  According to the first aspect of the present invention, the exhaust gas purified by passing through the particulate filter catalyst and / or the oxidation catalyst reaches the drain reservoir portion and is then discharged from the exhaust gas outlet.

  In this case, the drain on the downstream side of the particulate filter catalyst and / or the oxidation catalyst is accumulated in the drain reservoir portion, so that the drain flows back to the particulate filter catalyst and / or the oxidation catalyst side. Therefore, it is possible to reliably reduce the occurrence of deterioration such as cracks in the particulate filter catalyst and / or oxidation catalyst.

  As described in claim 2, the drain accumulated in the drain reservoir is discharged from a drain removing means provided at the bottom of the drain reservoir at an appropriate time.

  In this case, as described in claim 3, by providing guide means for guiding the drain to the drain reservoir in the purification case, the drain can be quickly and smoothly collected in the drain reservoir. Therefore, the backflow of drain to the catalyst side can be more reliably prevented.

  According to a fourth aspect of the present invention, the drain discharging means is a solenoid valve, so that the drain is automatically discharged when the operation of the internal combustion engine is stopped. It can be easily configured to be performed at appropriate time intervals or to be performed remotely.

  In particular, the configuration described in claim 5 has the effect of facilitating maintenance such as replacement or cleaning of the particulate filter catalyst and / or oxidation catalyst in addition to the above-described effect.

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

  1 to 3 show a first embodiment.

  1 to 3, reference numeral 1 denotes a purification case made of a refractory metal material, and the purification case 1 is configured to have a cylindrical shape such as a horizontal cylinder or a horizontal cylinder whose axis is horizontal. The inside of one end is provided with a first bottom plate 2, the other end is opened, and the opening at the other end is a lid body 3 or a band body 4 or a plurality of bolts or clip bodies with respect to the other end. It is blocked by detachably joining with, for example.

  An exhaust gas inlet pipe 5 from a diesel engine (not shown) is provided at one end of the purification case 1, and an exhaust gas outlet pipe 8 is provided on the upper surface of the purification case 1 so as to protrude upward. A chamber 7 is formed on the lower surface of the drain reservoir 6 that communicates with the inside of the purification case 1.

  A plug 10 that closes the drain hole 9 provided in the bottom of the chamber 7 is detachably screwed.

  In this case, instead of plugging the drain hole 9 with a plug 10 that is detachably screwed into the drain hole 9, an electromagnetic valve is provided in the drain hole 9 if necessary. Needless to say, it can be configured.

  An inner case 11 having a smaller diameter than the inner diameter is inserted into the purifying case 1, and the inner end of the inner case 11 on the first bottom plate 2 side is closed. A second bottom plate 12 is provided, and exhaust gas from the exhaust gas inlet pipe 5 is introduced. Further, in the inner case 11, the chamber 7 with the drain reservoir 6 and the exhaust gas outlet are provided. The end portion on the tube 8 side is fixed to the inner surface of the purification case 1 through a joint portion 13 formed in a plane perpendicular to the axes of the purification case 1 and the inner case 11.

  Between the purification case 1 and the inner case 11 inserted therein and between the first bottom plate 2 and the second bottom plate 12, a heat insulating material such as glass wool 14 is filled.

  On the other hand, in FIGS. 1 to 3, reference numeral 15 denotes a filter case configured so as to be inserted into the inner case 11, and a particulate filter catalyst 16 is incorporated in the filter case 15. Yes.

  The filter case 15 is removably inserted into the inner case 11 of the purification case 1 with the lid 3 removed from the opening at the other end of the purification case 1. It is fixed to the purification case 1 by being pressed in the axial direction by an elastic means such as a coil spring 17 interposed between the lid 3 and the like.

  An end of the filter case 15 on the exhaust gas inlet pipe 5 side is opened in the inner case 11 so that exhaust gas from the exhaust gas inlet pipe 5 flows into the filter case 15. On the other hand, at the end of the filter case 15 on the chamber 7 side, a plurality of communication holes 18 into the purification case 1 are formed.

  In the purification case 1, a guide means is provided in the portion on the chamber 7 side to guide the drain on the outer peripheral surface of the filter case 15 to the drain reservoir 6.

  That is, as shown in FIG. 2, each communication hole 18 in the filter case 15 is provided with a louver 19 so as to be inclined outward in the radial direction and downward. The drain is prevented from entering the filter case 15 again from the communication holes 18, and the drain flows smoothly to the drain reservoir 6.

  Further, the lid 3 is formed in a hat shape, and a resonance chamber 21 communicating with the inside of the gas-liquid separation chamber 6 through a small communication pipe 20 is formed therein.

  In the first embodiment, the exhaust gas flowing from the exhaust gas inlet pipe 5 is entirely fed into the filter case 15 into a portion of the inner case 11 adjacent to the exhaust gas inlet pipe 5. A perforated plate 22 is provided as a rectifying means for dispersion.

  In this configuration, exhaust gas from the diesel engine flows into the filter case 15 via the exhaust gas inlet pipe 5 and is purified when passing through the particulate filter catalyst 16 in the filter case 15. From the communication hole 18 to the inside of the purification case 1, the exhaust gas outlet pipe 8 side part is reached, and after being silenced in the resonance chamber 21 formed in the lid 3 in this part, the exhaust gas is discharged through the exhaust gas outlet pipe 8. The

  In the portion of the purification case 1 on the exhaust gas outlet pipe 8 side, the drain on the downstream side of the particulate filter catalyst 16 is collected so as to enter the drain reservoir 6 in the chamber 7 and collected. The drain is discharged out of the drain reservoir 6 by removing the plug 10 or opening the solenoid valve at an appropriate time.

  Further, each communication hole 18 from the inside of the filter case 15 to the inside of the purification case 1 is provided with a louver 19 that is inclined outwardly in the radial direction and downward, so that the filter case 15 It is possible to reliably prevent the drain on the outer surface from entering the filter case 15 through the communication holes 18 and to smoothly flow down the drain to the drain reservoir 6.

  Further, the periphery of the filter case 15 is surrounded by a heat insulating material such as glass wool 14 filled between the purification case 1 and the inner case 11, and heat dissipation to the atmosphere is prevented. Since the particulate filter catalyst 16 can be maintained at a high temperature, a high purification rate can be ensured.

  In the first embodiment, the particulate filter catalyst 16 is built in the filter case 15 in order to cope with the exhaust gas in the diesel engine. Depending on the nature of the exhaust gas to be purified and the purified matter in the exhaust gas, an oxidation catalyst is built in instead of the particulate filter catalyst, or both the particulate filter catalyst 16 and the oxidation catalyst are built in. It goes without saying that it can be configured.

  The filter case 15 can be freely inserted and removed from the opening at the other end of the purification case 1 in a state where the lid 3 at the other end of the purification case 1 is removed. Maintenance such as replacement or cleaning of the curated filter catalyst 16 and / or the oxidation catalyst can be facilitated.

  Further, a heat insulating material such as glass wool 14 filled between the purification case 1 and the inner case 11 is bonded to the inner surface of the purification case 1 at the end of the inner case 11 on the gas-liquid separation chamber 6 side. Since it is sealed by the portion 13, the inner case 11 can be stably supported, and the heat insulating material such as the glass wool 14 is reliably prevented from being lost by being drawn by the flow of the exhaust gas. be able to.

  Furthermore, the filter case 15 in the purification case 1 is fixed to the purification case 1 by being pressed in the axial direction by an elastic means such as a coil spring 17. Since the thermal expansion and contraction in the axial direction can be absorbed by the elastic means, the filter case 15 is in a state in which free thermal expansion and contraction in the axial direction in the filter case is allowed by the elastic means. And can be fixed and fixed securely.

  Next, FIG. 4 shows a second embodiment.

  In the second embodiment, a flange 23 is integrally provided on the outer periphery of the filter case 15, and the flange 23 is connected to the fixed joint 13 when the filter case 15 is inserted into the inner case 11. In this configuration, the gasket 24 is held between them, and a plurality of bolts 25 are fastened in a detachable manner. The other configurations are the same as those of the first embodiment.

  In the second embodiment, the flange 23 on the outer periphery of the filter case 15 is joined to the fixed joint 13 with a gasket 24 sandwiched therebetween, so that the filter case 15 is more The exhaust gas from the exhaust gas inlet pipe 5 leaks directly to the exhaust gas outlet pipe 8 from the gap between the inner case 11 and the filter case 15 while being able to be fixed stably. Can be reliably prevented.

  According to the second embodiment, the filter case 15 can be provided with a handle 26 for handling such as carrying it.

It is a vertical front view which shows the purification apparatus by 1st Embodiment. FIG. 2 is a sectional view taken along line II-II in FIG. 1. It is an exploded view of the purification device. It is a vertical front view which shows the purification apparatus by 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Purification case 2 1st bottom plate 3 Cover body 5 Exhaust gas inlet pipe 6 Drain pool part 7 Header 8 Exhaust gas outlet pipe 9 Drain hole 10 Plug 11 Inner case 12 2nd bottom board 13 Adhesion | bonding part 14 Glass wool (heat insulation) Material)
15 Filter case 16 Particulate filter catalyst 17 Coil spring 18 Communication hole 19 Louver 27 Drain pool

Claims (5)

In an exhaust gas purification apparatus comprising an exhaust gas inlet to the catalyst and an exhaust gas outlet from the catalyst in a purification case containing either one or both of a particulate filter catalyst and an oxidation catalyst,
An exhaust gas purifying apparatus for an internal combustion engine, wherein a drain accumulating portion is provided between the catalyst and the exhaust gas outlet in the purifying case so as to accumulate drain on the downstream side of the catalyst.   2. The exhaust gas purifying apparatus for an internal combustion engine according to claim 1, wherein the drain reservoir portion is provided with drain removing means at the bottom thereof.   3. The exhaust gas purification apparatus for an internal combustion engine according to claim 2, further comprising guide means for guiding the drain to the drain pool portion inside the purification case.   4. The exhaust emission control device for an internal combustion engine according to claim 2, wherein the drainage means is an electromagnetic valve.   5. An exhaust emission control device for an internal combustion engine according to claim 1, wherein the catalyst is built in a filter case removably inserted into the purification case.

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