DE112011101624T5 - Device and system for retaining debris and catching sparks - Google Patents

Abstract

The present document describes various embodiments of an apparatus and system for retaining debris and trapping sparks which overcomes at least some of the shortcomings of prior art approaches. According to one embodiment, an apparatus (230) for mitigating damage to an exhaust aftertreatment device (210) in an internal combustion engine system (100) capable of generating an exhaust flow is disclosed. The apparatus includes a housing (231) including an exhaust inlet (232), an exhaust outlet (234), and an exhaust flow passage (344) disposed between the exhaust inlet and outlet. Further, the apparatus includes a tubular mesh screen (236) disposed substantially entirely within the exhaust gas flow passage. The mesh screen includes a closed end (250) disposed proximate the exhaust inlet of the housing and an opposite open end (342) disposed proximate the exhaust outlet of the housing. The grille screen is adapted to capture particulate matter from damaged exhaust aftertreatment devices located within the exhaust stream.

Description

TERRITORY

This disclosure relates to exhaust aftertreatment systems for internal combustion engines, and more particularly to an apparatus and system for retaining debris and trapping sparks in an exhaust aftertreatment system for a diesel-fueled internal combustion engine.

BACKGROUND

The exhaust regulations for internal combustion engines have been steadily tightened in recent years. For example, the prescribed emission levels for NOx and particulates from diesel-fueled internal combustion engines are so low that emissions levels can not be met in many cases with improved combustion technologies. Therefore, engines are increasingly being provided with exhaust aftertreatment systems to reduce harmful exhaust emissions. Typical exhaust aftertreatment systems include any of various devices designed to reduce the level of harmful emissions in the exhaust. For example, some exhaust aftertreatment systems for diesel-fueled internal combustion engines include various components such as a diesel oxidation catalyst (DOC), a particulate filter or diesel particulate filter (DPF), and a selective catalytic reduction (SCR) catalyst. In some exhaust aftertreatment systems, the exhaust flows first through the diesel oxidation catalyst, then through the diesel soot particulate filter and then through the SCR catalyst.

Each of the DOC, DPF, and SCR catalyst devices is configured to subject exhaust gas passing through or over the respective device to a particular exhaust emission treatment operation. The DOC, DPF, and SCR catalyst each include a catalyst bed or substrate that facilitates the corresponding process for exhaust emission treatment. In general, the catalyst bed of the DOC reduces by oxidation techniques the amount of carbon monoxide and hydrocarbons contained in the exhaust gas. The substrate of the DPF filters out harmful diesel particulates and soot from the exhaust gas. The catalyst bed of the SCR catalyst finally reduces the amount of nitrogen oxides (NOx) contained in the exhaust gas.

Unfortunately, the substrates of DOC, DPF, and SCR catalyst may suffer damage due to any of various conditions, such as age, vibration, high temperature events, and so on. Substrate damage often has catastrophic consequences, namely when parts of the substrates break off and enter the exhaust gas. Although typical on-board diagnostic systems warn an operator that the components are damaged, conventional systems are not equipped to trap the fragments of damaged substrates before they enter the atmosphere. The discharge of damaged pieces of substrate into the atmosphere is undesirable because the pieces of substrate may have deleterious effects on the environment. In general, conventional diesel powered engine systems do not include damage reduction devices to intercept pieces of damaged aftertreatment devices, as such devices add to increased footprint and significantly increased flow restriction of the exhaust.

In addition to the above exhaust emission reduction requirements, current regulations require the use of spark arresters in engine systems for certain industrial applications. The US Department of Agriculture (USDA), for example, requires that motor systems must have spark arresters when used in nature reserves, such as forests. Proper spark arresters must absorb sparks that exceed a legal regulatory limit before discharging the sparks into the atmosphere. Generally, sparks involve flammable materials or incandescent debris that can cause fires when ejected into the atmosphere.

Conventional spark arresters include stator-type spark arresters and sieve-type spark arrestors. Stator-like spark arresters catch sparks by creating centrifugal forces through blades that separate the sparks from the exhaust gas. Sieve-type spark arresters catch sparks using a fine mesh screen, with the sparks retained on the screen. Stator-type spark arresters are typically larger, bulkier, and more complex than wire-type spark arresters because smaller stator-type spark arrestors would result in a significant increase in exhaust drag. Furthermore, in many motor systems, stator-type spark arresters are not suitable for trapping large sparks or damaged substrate pieces. Although sieve-type spark arresters are smaller than stator spark arresters and result in lower exhaust resistance, they tend to settle quickly with soot. Accordingly, the use of conventional sieve-type spark arresters has been limited to non-soot gasoline powered engine systems.

SUMMARY

The subject matter of the present application has been developed in light of the current state of the art, and in particular with regard to the objects and needs within this field, which have not yet been fully solved by the currently available fragment retainers and spark arresters. Accordingly, the subject matter of the present application has been developed to provide an apparatus and system for retaining debris and trapping sparks which overcomes at least some shortcomings of prior art approaches.

According to one embodiment, a damage mitigation apparatus is disclosed in an exhaust aftertreatment device in an internal combustion engine system that is capable of generating an exhaust stream. The apparatus includes a housing that includes an exhaust inlet, an exhaust outlet, and an exhaust flow passage disposed between the exhaust inlet and outlet. Further, the apparatus comprises a tubular mesh screen disposed substantially entirely within the exhaust gas flow passage. The mesh screen includes a closed end disposed proximate the exhaust inlet of the housing and an opposite open end disposed proximate the exhaust outlet of the housing. The grille screen is adapted to capture particulate matter from damaged exhaust aftertreatment devices located within the exhaust stream.

In certain implementations of the apparatus, the mesh screen limits an interior space whose cross-sectional area increases from the closed to the open end. In some implementations, the cross-sectional area of the interior near the open end is approximately equal to the cross-sectional area of the exhaust outlet of the housing. The cross-sectional area of the exhaust outlet of the housing may be approximately equal to the largest cross-sectional area of the exhaust gas flow channel.

According to some implementations, the open end of the mesh screen is attached directly to the inner surface of the housing. The exhaust inlet of the housing may be releasably coupled to an exhaust outlet of an upstream exhaust after-treatment device. Similarly, the exhaust outlet of the housing may be configured to engage an exhaust inlet of a downstream exhaust after-treatment device. In addition, the housing of the device may have a length that is between approximately 8 inches and approximately 10 inches. In certain implementations, the grid screen includes sidewalls that extend from the closed end to the open end at an angle of at least about 5 ° apart.

In another embodiment, the exhaust aftertreatment system for a diesel-fueled internal combustion engine includes a diesel particulate filter and a catcher disposed downstream of the diesel particulate filter. The diesel particulate filter is in communication with the diesel-powered internal combustion engine so as to receive the exhaust gas. In addition, the diesel particulate filter includes a filter substrate for trapping particulate matter present in the exhaust gas. The catcher communicates with the diesel particulate filter such that it receives the exhaust gas. In addition, the catcher comprises a mesh screen through which flows all the exhaust gas which the catcher receives. The mesh screen includes a plurality of apertures sized to intercept sparks whose magnitude exceeds a threshold. The sparks are generated by the diesel-powered internal combustion engine. The plurality of openings is further sized to intercept broken pieces of size exceeding a threshold, wherein the broken pieces of damaged components may be parts of a damaged aftertreatment device located upstream of the catcher.

In some implementations, the exhaust aftertreatment system further includes a diesel oxidation catalyst located upstream of the diesel particulate filter and a selective catalytic reduction catalyst disposed downstream of the diesel soot particulate filter and upstream of the catcher. The damaged aftertreatment device includes at least one of the diesel particulate filter, the diesel oxidation catalyst, and the selective catalytic reduction catalyst. The catcher may be configured to cause an increase in exhaust backpressure of less than about 0.5 in-Hg within the exhaust aftertreatment system.

According to certain implementations, the catcher includes an exhaust inlet and an exhaust outlet. The mesh screen may include a closed end and an open end opposite the closed end. The closed end may be closer to the exhaust inlet of the catcher than the open end. Alternatively, in other implementations, the open end may be closer to the trap inlet than the closed end.

The exhaust aftertreatment system may further comprise a housing for components and a Exhaust after-treatment device disposed within the housing. The catcher may be disposed within the housing for components downstream of the exhaust aftertreatment device. The catcher may also be external and capable of being releasably secured to the housing for components.

In another embodiment, an internal combustion engine system includes a diesel-fueled internal combustion engine that is capable of generating an exhaust gas flow. The system further includes an exhaust aftertreatment system in communication with the diesel-powered internal combustion engine to receive the exhaust gas. The aftertreatment system includes a diesel particulate filter with a filter substrate for trapping particulates present in the exhaust stream. The system may further include a catcher disposed downstream of the diesel particulate filter and in communication with the diesel particulate filter to receive the exhaust gas. The catcher comprises a generally tubular mesh screen through which all of the exhaust gas which the catcher receives flows. The grating screen includes a plurality of apertures sized to intercept sparks whose magnitude exceeds a threshold and fragments of damaged components whose magnitude exceeds the threshold.

In certain implementations of the internal combustion engine system, the diesel-powered internal combustion engine produces at least 50 Anglo-American horsepower. In other implementations, the diesel-powered internal combustion engine produces at least 500 Anglo-American horsepower. In some implementations, the diesel-powered internal combustion engine and the exhaust aftertreatment system satisfy at least one of Emission standards US Tier 4 and Euro IIIb ,

Throughout the present specification, references to features, advantages, or similar statements are in no way to be considered as including, or needing to be, any of the features and advantages that can be practiced with the subject matter of the present disclosure in any particular embodiment. Rather, statements referring to features and advantages are to be understood as embodying specific features, advantages, or distinctive features described in connection with an embodiment in at least one embodiment of the present disclosure. Throughout the present specification, therefore, discussions of features and advantages and similar statements may refer to the same embodiment, but not necessarily so.

In addition, the described features, advantages and characterizing features of the subject matter of the present disclosure may be combined in any suitable manner in one or more embodiments. Those skilled in the art will recognize that the subject matter may be practiced even if one or more of the specific features or advantages of a particular embodiment are not met. In other instances, certain embodiments may recognize additional features and benefits that may not be present in all embodiments. These features and advantages will become more apparent from the following description and the appended claims, or may be learned by practice of the object recited below.

BRIEF DESCRIPTION OF THE DRAWINGS

To better understand the advantages of the subject matter, a more detailed description of the subject matter described above will be made with reference to specific embodiments illustrated in the accompanying drawings. By indicating that only typical embodiments of the subject matter are illustrated in these drawings and are therefore not to be construed as limiting the scope thereof, the subject matter will be described and explained in more specific and more particular terms with reference to these drawings, wherein:

1 Figure 3 is a schematic block diagram of an internal combustion engine having an exhaust aftertreatment system and a catcher according to a representative embodiment;

2 an exploded perspective view of an exhaust aftertreatment system according to one embodiment;

3 Figure 4 is a side cross-sectional view of a catcher according to one embodiment; and

4 a side cross-sectional view of a catcher according to another embodiment is.

DETAILED DESCRIPTION

Throughout the present specification, reference to "the embodiment", "an embodiment" or similar statements shall be construed as giving certain features, structures or distinctive features described in connection with this embodiment in at least one embodiment of the present disclosure are. In the However, throughout the present description, the words "in this embodiment", "in one embodiment" or similar statements may always refer to the same embodiment, but not necessarily so. Similarly, the use of the term "implementation" means that there is implementation with certain features, structures, or characteristics described in connection with one or more embodiments of the present disclosure, a reaction always being associated with one or more embodiments can be, unless it is expressly made a different type of connection.

Moreover, the described features, advantages or characterizing features of the subject matter described herein may be combined in any suitable manner in a single or multiple embodiments. In the following description, numerous specific details are given, such as examples of control devices, structures, devices, algorithms, programming, software modules, user selections, hardware modules, hardware circuits, hardware chips, etc. that are intended to provide a thorough understanding of embodiments of the subject matter. One skilled in the art will recognize, however, that the subject matter may be practiced even in the absence of one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not illustrated or described in detail to avoid obscuring other aspects of the disclosed subject matter.

1 shows an embodiment of an internal combustion engine system 100 , To the main components of the engine system 100 belong to an internal combustion engine 110 and an exhaust aftertreatment system 120 which is coupled to the engine. In the internal combustion engine 110 it may be a compression-ignition internal combustion engine, such as a diesel-powered engine. In some embodiments, the diesel engine provides 110 at least about 50 Anglo-American horsepower. In certain other embodiments, the diesel engine provides 110 at least about 500 Anglo-American horsepower. In some embodiments, the engine system suffices 100 newer emission standards, such as at least one of Emission standards US Tier 4, the emission standards Euro IIIb and beyond.

Inside the internal combustion engine 110 Atmospheric air is combined with fuel to power the engine. The combustion of fuel and air produces exhaust gas. At least a subset of the engine 110 generated exhaust gas is in operation via the exhaust aftertreatment system 120 dissipated. In certain implementations, the engine system includes 100 an exhaust gas recirculation (EGR) line (not shown) configured to receive a subset of that from the engine 110 generated exhaust gas can be returned to the engine to the combustion characteristics of the engine 110 to change.

In general, the exhaust aftertreatment system 120 designed to remove various chemical compounds and particulate emissions present in the exhaust stream from the engine 110 is recorded. The exhaust aftertreatment system 120 includes a Diesel Oxidation Catalyst (DOC) 130 , a diesel particulate filter (DPF) 140 and an SCR system 150 , In an exhaust gas flow direction indicated by directional arrows between the components of the exhaust aftertreatment system, the exhaust gas may be from the engine 110 through the DOC 130 , by the DPF 140 and through the SCR system 150 stream. In other words, in the illustrated embodiment, the DPF is 140 downstream of the DOC 130 arranged, and the SCR system 150 is downstream of the DPF 140 arranged. In other embodiments, the components of the exhaust aftertreatment system 120 may be arranged in any of various arrangements, and the system may be downstream of the SCR system 150 other components, such as an AMOX catalyst (not shown), or less components include. In general, exhaust gas contains in the exhaust aftertreatment system 200 treated and then released to the atmosphere, significantly less pollutants, such as diesel particulates, NOx, hydrocarbons such as carbon monoxide and carbon dioxide, as untreated exhaust gas.

At the DOC 130 it can be any of a variety of flow through oxidation catalysts. In general, the DOC includes 130 a substrate having an active catalyst layer adapted to oxidize at least some of the particulates (eg, the soluble organic soot fraction) in the exhaust gas and to reduce the unburned hydrocarbons and CO to less environmentally harmful compounds. In some implementations, the DOC 130 For example, reduce the levels of hydrocarbons and CO in the exhaust sufficiently to meet applicable emission standards.

At the DPF 140 It may be any of the various particulate filters known in the art, wherein it is designed to reduce the concentrations of particles, e.g. To reduce soot and ash in the exhaust to meet the applicable emission standards. The DPF 140 includes a filter substrate that traps soot and other particles from the engine 110 be generated. The engine system 100 regenerates the DPF 140 at regular intervals to remove particles that have accumulated on the DPF over time. In essence, the DPF 140 regenerated by increasing the temperature of the exhaust gas so that it exceeds a temperature threshold associated with the burning of the particles.

The SCR system 150 includes a reductant delivery system and an SCR catalyst disposed downstream of the reductant delivery system. The reductant delivery system may be operated to inject or meter a reductant into the exhaust before the gas enters the SCR catalyst. The injected reductant (or decomposed by-product of the reductant, such as in the reduction of urea to form ammonia) react with NOx in the presence of the SCR catalyst to reduce NOx in the exhaust to less harmful emissions such as N2 and H2O. The SCR catalyst may be any of various catalysts known in the art. For example, in some implementations, the SCR catalyst is a vanadium based catalyst, and in other implementations the SCR catalyst is a zeolite based catalyst, such as a Cu zeolite or a Fe zeolite catalyst , Like the filter substrate of the DPF 140 For example, the SCR catalyst may be exposed to high temperatures, such as while the DPF is being regenerated.

Any of the catalyst or filter substrates of the DOC 130 , the DPF 140 and the SCR system 150 can be damaged due to any of various conditions. For example, both high exhaust gas temperature events (eg, DPF regeneration events) and high vibration environments and the relative age of the individual items can result in damage to the substrates. The damage to the substrates may be minor (eg, cracking) or severe (eg, disintegration of the substrate). Minor damage to the substrates can be detectable and recoverable before they have a significant negative impact on the environment. In contrast, severe damage can often only be remedied if parts of the substrate have been released to the environment. Conventional diesel-fueled engine systems employing exhaust aftertreatment devices have no debris retaining elements for damaged substrates, particularly when the damaged substrate is associated with a DPF or a downstream SCR catalyst. Accordingly, in diesel powered engine systems, fragments of damaged substrate would be released to the environment before damage reduction measures could be implemented.

In addition to possible substrate emissions due to severe damage to a substrate of an exhaust aftertreatment device, internal combustion engines may leak sparks. Due to the hazardous and flammable nature of released sparks, the USDA requires certain engine systems to be equipped with spark arresters when used within protected areas. One common application involves the use of engine systems on certain vehicles and / or non-vehicular equipment operating in forest areas. Conventionally, in order to comply with the USDA regulations on spark arresters, gasoline powered engine systems must use sieve-type spark arrestors and diesel-powered engine systems must use stator-type spark arrestors. Screened spark arresters are better suited to gasoline powered engine systems because they are smaller and since screened spark arresters have less obstruction. Stator-type spark arresters are commonly used with diesel-powered engine systems because the high soot and particulate emissions of previous diesel engines would quickly clog up screen-like catchers.

Although this is in contrast to conventional techniques, the diesel engine system includes 100 In the present disclosure, a sieve-like catcher 160 or such particle retention member located downstream of the DOC 130 , the DPF 140 and the SCR system 150 to accomplish the dual task of a damaged substrate retention element and a spark collector (see 1 ). The catcher 160 generally absorbs 100% of the exhaust gas emitted by the DOC 130 , the DPF 140 and the SCR system 150 flows. The catcher 160 serves to mitigate the consequences of severe damage to components of the exhaust aftertreatment system by intercepting parts or fallen portions of damaged components on a grid-like screen before they are released to the environment. Similarly, the grid-like sieve of the catcher 160 designed to catch sparks from the engine 110 before they are released into the environment as prescribed by the USDA. In some implementations is the catcher 160 in line with the components of the exhaust aftertreatment system 120 and can be connected to it separately. For example, in one implementation the DOC 130 , the DPF 140 and the SCR catalyst of the SCR system 150 housed in a single housing having a housing outlet. In this implementation, the catcher 160 releasably coupled to the housing outlet. In other implementations is the catcher 160 inserted into the housing of an aftertreatment device, such as an outlet portion of the SCR system 150 , For example, the catcher 160 be disposed within a housing of a Nachbehandlungsbauteelements immediately upstream of the housing outlet.

As in 2 includes a diesel engine system 200 an exhaust aftertreatment system 220 with a catcher 230 according to one embodiment. The aftertreatment system 220 includes a housing or a sleeve 210 an aftertreatment element, within which one or more emission-reducing components are housed. According to one embodiment, in the housing 210 housed at least one of the elements DOC, DPF and SCR catalyst. In the illustrated embodiment is in the housing 210 housed at least one DPF. The housing 210 includes an exhaust inlet 212 and an exhaust outlet 214 , The exhaust gas generated by an engine flows through the inlet 212 in the housing, the / the component (s) within the housing 210 Reduce emissions that are present in the exhaust, and the exhaust gas flows through the outlet 214 out of the case. The housings of the present disclosure may be made of any of a variety of materials, such as metal or metal alloys.

The catcher 230 includes a housing 231 extending from an inlet end 232 to an outlet end 234 extends. In certain implementations, it is the case 231 around a generally cylindrical hollow box. The inlet end 232 of the housing 231 defines an inlet, and the outlet end 234 of the housing limits an outlet of the catcher 230 , In the case 231 is a lattice screen 236 housed extending from a closed inlet end 250 near the inlet end 232 of the housing 231 up to an open outlet end (not shown) in the vicinity (for example, adjacent, joined together, and / or with the same extent) of the outlet end 234 of the housing extends. The lattice screen 236 is arranged (eg, rolled up) such that it assumes a three-dimensional shape that defines an interior space. Exhaust gas, which via the inlet at the inlet end 232 in the case 231 passes through the mesh screen 236 in the interior, before placing the housing over the outlet at the outlet end 234 leaves. Since the closed inlet end 250 of the mesh screen 236 is closed or closed and the open outlet end is generally the same extent as the outlet end 234 of the housing 231 has, all the exhaust gas, which flows into the housing 231 the catcher 230 passes through the screen 236 ,

The lattice screen 236 may be arranged in any of various arrangements. Preferably, the grid screen 236 generally elongated and tubular so as to define a hollow interior channel. The grid screen may have any of various shapes such that the hollow interior channel has any of various cross-sectional shapes and yet is generally tubular. In other words, the grid screen 236 not cylindrical, but still tubular. To save space while improving performance, the closed inlet end 250 of the sieve 236 compressed and folded so that it has a generally "X-shaped" or "+ -shaped" impermeable finish 252 forms. In the course of the extension of the sieve 236 from the closed inlet end 250 toward the open outlet end, the screen unfolds or expands to form a generally circular opening at the open outlet end. Although the closed inlet end 250 In the illustrated embodiment, it is generally "X-shaped" or "+ -shaped", the closed inlet end of the mesh screen 236 in other embodiments have other shapes, such as circular, rounded, pointed, polygonal, rectilinear, etc.

The lattice screen 236 includes a plurality of openings of specific size, shape and number. The size and shape of the openings are selected to pass particles whose size is below a threshold and to prevent the passage of particles whose size exceeds the threshold. The size threshold may be any of a variety of sizes, the selection of which is based on any of a variety of factors. However, in some implementations, the size threshold is based on thresholds set by the government. For example, in one implementation, each of the openings of the lattice sheet has a maximum dimension of about 0.023 inches. In general, the number of openings will be as high as the material from which the mesh screen 236 is made, allowed. Preferably, the grid screen 236 from a mesh screen made of metal wire, such as a grid of stainless steel wire. In these implementations, the number of openings is based on the size and strength of the wires forming the screen. In other implementations, the lattice sieve exists 236 from a tightly perforated material. The lattice screen 236 is also designed to cause the least possible backpressure. In certain implementations amounts to For example, the increase in exhaust backpressure (ie, obstruction) caused by the catcher is less than about 0.5 in Hg.

The catcher 230 is detachable to the exhaust outlet 214 of the housing 210 coupled. The inlet end 232 of the catcher housing 231 includes a stepped portion whose size is adapted to the exhaust outlet 214 of the housing 210 take. More specifically, the inner diameter of the inlet end 232 approximately the same as the outer diameter of the exhaust outlet 214 while the inner diameter of the inlet end 232 approximately the same as the inner diameter of the exhaust outlet 214 is. In this way, the exhaust outlet becomes nestable in the inlet end 232 of the catcher housing 231 recorded that the inner surfaces of the exhaust outlet 214 and the catcher inlet end 232 are essentially flush. The inlet end 232 may include recesses (see, for example, the recesses 380 of the 3 ) to the fixed joint of the inlet end around the exhaust outlet 214 to facilitate. In the illustrated embodiment, the fixed joining of the inlet end takes place 232 around the exhaust outlet 214 by means of a clamp 238 which is struck around the inlet end.

Another component for exhaust aftertreatment 220 and a housing 221 can to the outlet end 234 the catcher 230 coupled, if desired. In certain implementations, the device may be 220 For example, to act a sound attenuation device with a housing having an exhaust inlet 222 having. Similar to the inlet end 232 the catcher 230 takes the exhaust inlet 222 of the housing 221 the outlet end 234 the catcher on exactly. The exhaust inlet 222 of the component 220 is by means of a clamp 224 that the clamp 238 similar, firmly to the outlet end 234 together.

The detachable connection between the component housings 210 . 221 and the catcher 230 is the serviceability of the catcher 230 conducive. If the catcher 230 For example, is filled with trapped particles, the catcher 230 be serviced without difficulty by removing the clamps 224 . 238 be solved and the catcher 230 is removed. After the maintenance of the catcher 230 (where, for example, the trapped particles from the sieve 236 can be removed) the catcher 230 back in the system 200 be installed by the exhaust outlet 214 of the housing 210 and the inlet end 232 the catcher are accurately mated, the exhaust inlet 222 of the housing 221 and the outlet end 234 the catcher are snugly fitted, and the clamps 224 . 238 be tightened. Alternatively, the waited catcher 230 be installed on another system. That way the catcher can 230 serviced without difficulty and reused on the same or a different system.

According to another embodiment, in 3 includes a catcher 330 , the catcher 230 similar is a case 331 extending from an inlet end 332 up to an outlet end 334 extends. In certain implementations, it is the case 331 around a pipe or a can with an outer surface 371 , which is exposed to the environment, and an inner surface 372 which is opposite to the outer surface. The housing 331 defines an inner exhaust flow channel 344 through which the exhaust gas from an inlet 333 which is from an inlet end 332 is limited to an outlet 335 which is from an outlet end 334 is limited, flows. The housing 331 has a length equal to the distance between the inlet end 332 and the outlet end 334 is. In certain implementations, the length of the housing is between about eight inches and about ten inches. Furthermore, in some implementations, the approximate diameter of the inner exhaust gas flow passage is 344 between about four inches and about five inches. In a specific implementation, the housing has 331 a length of about eight inches and an inner diameter of about four inches (ie, a length to diameter ratio of about 0.5). In another specific implementation, the housing has 331 a length of about ten inches and an inner diameter of about five inches (ie, a length to diameter ratio of about 0.5).

Just like the catcher 230 includes the catcher 330 a mesh screen 336 that is from a closed end 340 to an open end 342 extends. The lattice screen 336 is shaped so that it has an interior 345 limited. The closed or closed end 340 is compressed and generally forms an "X-shaped" or "+ -shaped" opaque termination 346 that's the closed end 250 of the mesh screen 236 the catcher 230 is similar. The impermeable conclusion 346 can be made by the closed end 340 of the sieve 336 is folded using any of various folding techniques. The open end 342 defines a generally circular opening. Accordingly, the cross-sectional shape of the interior undergoes 345 along a plane perpendicular to the exhaust gas flow direction 360 is a gradual transition from a general "X-shape" or "+ -form" to a shape that is generally circular. Similarly, the cross-sectional area of the interior decreases 345 along a plane perpendicular to the exhaust gas flow direction 360 is of a minimum area near the impermeable termination 346 to a maximum area near the open end 342 gradually closed. As can be seen from the illustration, the maximum cross-sectional area of the interior is the same 345 along a plane perpendicular to the exhaust gas flow direction 360 is about the maximum cross-sectional area of the inner channel 344 (except the section of the inner channel 344 , which from the coupling stage 370 of the inlet section 332 is limited).

The radially outermost sections or sidewalls 352 of the mesh screen 336 show in an exhaust gas flow direction through the directional arrows 360 . 364 is indicated, a radially outwardly directed angular position. In other words, run the radially outermost side walls 352 of the mesh screen 336 in the exhaust gas flow direction 360 . 364 apart. In some implementations, the radially outermost sidewalls are running 352 at an angle θ which is between about 5 ° and about 60 °. In a particular implementation, the angle θ is about 30 °. The grid type and arrangement of the sieve 336 can the sieve 236 be similar to.

The lattice screen 336 has a length defined by the distance between the closed end 340 and the open end 342 is fixed. In the illustrated embodiment, the length of the mesh screen is 336 less than a length of the housing 331 these being between limits through the inlet end 332 and the outlet end 334 lies. Accordingly, in the illustrated embodiment, the grating screen 336 completely in the case 331 contain. The lattice screen 336 is to the case 331 coupled by a tab section 354 of the open end 342 of the mesh screen 336 and the inner surface 372 of the housing interlock. More specifically, the tab portion becomes 354 to the inner surface 372 of the housing 331 glued or welded. In this way, the grid screen is directly on the inner surface 372 the case or the sleeve 331 attached. In other embodiments, the grid screen is 336 using other attachment or coupling techniques on the housing 331 attached. Regardless of the method of attaching the open end 342 on the housing 331 is the lattice screen 336 arranged so self-supporting that the closed end 340 is a free-floating or unpaved finish.

As in 3 can be seen, exhaust gas passes during operation 360 , which is undesirable particles 375 (eg, fragments of damaged substrate and / or engine sparks) across the inlet 333 in the case 331 the catcher 330 ,

After flowing through the inlet 333 the exhaust gas passes 360 in a room 348 that is between the lattice strainer 236 and the wall of the housing 331 is delimited. From the room 348 the exhaust gas passes 360 through a plurality of openings 350 of the mesh screen 336 in the interior 345 as by the directional arrows 362 is specified. Starting from the interior 345 the exhaust leaves the catcher 330 through the outlet 335 as by the directional arrows 364 is specified. If the exhaust 362 through the screen 336 flows, become unwanted particles 375 whose size exceeds a threshold, on the radially outer surface 353 intercepted by the lattice screen. Particles smaller than the size threshold may interact with the exhaust 362 through the openings of the lattice screen 336 reach.

The catcher described above 230 . 330 are designed so that they can be arranged as an independent component in a line with other components of an exhaust aftertreatment system. In other words, the catchers 230 . 330 physically independent of the other components of the system. However, in some embodiments, the catcher of the present disclosure may be integrated into an existing component of the aftertreatment system to trap particles of damaged substrate and sparks. Such as in 4 shown forms a catcher 430 according to one embodiment, a part of an existing device 420 an aftertreatment system. In the existing component 420 it may be an exhaust outlet section of a housing 410 within which a conventional exhaust emission reduction device (eg DOC, DPF, SCR catalyst) is located. The exhaust outlet section 420 includes a housing 422 that is between an exhaust inlet end 432 and an exhaust outlet end 434 extends. From the case 410 flows exhaust 460 through the inlet end 432 in the outlet section 430 and through the outlet end 434 out of the outlet section.

The catcher 430 includes a mesh screen 436 that the lattice sieves 236 . 336 is similar. However, the lattice screen is 436 in a different way than the lattice screens 236 . 336 shaped and arranged. For example, the grating screen comprises 436 an open inlet end 440 and a closed outlet end 445 , The lattice screen 436 may have a cross-sectional shape which is generally circular and whose area is along a plane perpendicular to the exhaust gas flow direction 460 is gradually reduced in the exhaust gas flow direction. In other embodiments, the grid screen 436 have other desirable cross-sectional shapes whose cross-sectional areas decrease in the exhaust gas flow direction. The open inlet end 440 has the same extent as the exhaust inlet end 432 of the housing 422 on, so all the exhaust gas flowing through the inlet end 432 of the housing 422 passes through the open inlet end 440 in a mesh screen 436 flows. In certain implementations, this is the open inlet end 440 near the exhaust inlet end 432 on an inner surface of the housing 422 attached (eg welded).

In operation, exhaust gas passes 460 , which is undesirable particles 470 contains, about the inlet end 432 in the outlet section 420 , After flowing through the inlet end 432 the exhaust gas passes 460 through the open inlet end 440 the catcher 430 in a room 444 , that inside the lattice screen 436 is delimited. From the room 444 the exhaust gas flows 460 through a plurality of openings 450 in the lattice screen 436 and leaves the catcher 430 as by the directional arrows 462 is specified. After the catcher 430 has left, the exhaust leaves the outlet section 420 by passing through the outlet end 434 flows as through the directional arrows 464 is specified. If the exhaust 462 through the screen 436 flows, become unwanted particles 470 whose size exceeds a threshold, at the radially inner surface 452 intercepted by the lattice screen. Particles smaller than the size threshold may interact with the exhaust 462 through the openings of the lattice screen 436 reach.

The lattice screen 336 the catcher 330 is with reference to the exhaust gas flow direction 360 aligned in a closed-to-open orientation. In contrast, the grid screen 436 the catcher 430 with reference to the exhaust gas flow direction 460 aligned in an open-to-closed orientation. Although not shown, in some embodiments, the grid screen is 336 with reference to the exhaust gas flow direction 360 aligned in an open-to-closed orientation, and the grating screen 436 is with reference to the exhaust gas flow direction 460 aligned in a closed-to-open orientation. Furthermore, in embodiments of the grid screen 436 that have a closed-to-open orientation, the closed end 445 of the mesh screen outside the outlet section 420 (eg, upstream of the inlet end 432 the outlet section within the component housing 210 ) can be arranged. Although the lattice screen 436 over its length has a generally circular cross-section, the lattice sieve 436 moreover, in a similar way to the lattice screens 236 . 336 the catcher 230 respectively 330 be shaped.

The present subject matter may be embodied in other specific forms without departing from its spirit or essential characterizing features. The described embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the invention thus follows from the appended claims and not from the foregoing description. All changes within the meaning of the claims and the scope of equivalency with them are to be included within their scope.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• Emission standards US Tier 4 and Euro IIIb [0016]
• Emissions standard US Tier 4, Euro IIIb emissions standard [0026]

Claims (20)

Apparatus for mitigating damage to an exhaust aftertreatment device in an internal combustion engine system capable of generating an exhaust flow comprising: a housing including an exhaust inlet, an exhaust outlet, and an exhaust gas flow passage located between the exhaust inlet and outlet; and a tubular mesh screen disposed substantially entirely within the exhaust gas flow passage, the mesh screen comprising a closed end disposed proximate the exhaust inlet of the housing and an opposite open end disposed proximate the exhaust outlet of the housing wherein the grid screen is adapted to trap particulates of damaged exhaust aftertreatment devices present in the exhaust flow. Apparatus according to claim 1, wherein the grating screen defines an interior space whose cross-sectional area increases from the closed to the open end. The apparatus of claim 1, wherein the cross-sectional area of the interior near the open end is approximately equal to the cross-sectional area of the exhaust outlet of the housing. The apparatus of claim 1, wherein the cross-sectional area of the exhaust outlet of the housing is approximately equal to a largest cross-sectional area of the exhaust flow channel. The device of claim 1, wherein the open end of the grating screen is attached directly to the inner surface of the housing. The apparatus of claim 1, wherein the exhaust inlet of the housing is releasably coupled to an exhaust outlet of an upstream exhaust aftertreatment device. The apparatus of claim 1, wherein the exhaust gas outlet of the housing is configured to engage an exhaust gas inlet of a downstream exhaust aftertreatment device. The device of claim 1, wherein the housing has a length that is between approximately 8 inches and approximately 10 inches. The device of claim 1, wherein the grating screen includes side walls that extend from the closed end to the open end at an angle of at least about 5 ° from each other. Exhaust after-treatment system for a diesel-powered internal combustion engine comprising: a diesel particulate filter in communication with the diesel-fueled internal combustion engine to receive exhaust gas, the diesel particulate filter comprising a filter substrate for trapping particulate matter present in the exhaust gas stream; and a catcher disposed downstream of the diesel particulate filter and in communication with the diesel particulate filter for receiving exhaust gas, the catcher comprising a grate through which flows all of the exhaust gas received by the catcher, the grate screen comprising a plurality of openings the size of which is such that the sparks generated by the diesel-powered internal combustion engine are trapped whose size exceeds a threshold, and fragments of damaged components whose size exceeds the threshold are trapped, the broken pieces of damaged components comprising parts of a damaged aftertreatment device is located upstream of the catcher. The exhaust aftertreatment system of claim 10, further comprising a diesel oxidation catalyst located upstream of the diesel particulate filter and a selective catalytic reduction catalyst disposed downstream of the diesel particulate filter and upstream of the catcher, the damaged aftertreatment device comprising at least one of the diesel soot particulate filter, diesel particulate filter. Oxidation catalyst and catalyst for selective catalytic reduction comprises. The exhaust after-treatment system of claim 10, wherein the catcher is configured to cause an increase in exhaust backpressure of less than about 0.5 in-Hg within the exhaust aftertreatment system. The exhaust aftertreatment system of claim 10, wherein the catcher comprises an exhaust inlet and an exhaust outlet, and wherein the mesh screen has a closed end and an open end opposite the closed end, the closed end being closer to the exhaust inlet of the catcher than the open end , The exhaust aftertreatment system of claim 10, wherein the catcher comprises an exhaust inlet and an exhaust outlet, and wherein the mesh screen has a closed end and an open end opposite the closed end, the open end being closer to the catch inlet of the catcher than the closed end , An exhaust after-treatment system according to claim 10, further comprising a housing for components and an exhaust aftertreatment device, which is disposed within the housing, wherein the catcher is disposed within the housing for components downstream of the exhaust aftertreatment device. The exhaust aftertreatment system of claim 10, further comprising a housing for components and an exhaust aftertreatment device disposed within the housing, the catcher being external and capable of being releasably secured to the housing for components. An internal combustion engine system comprising: a diesel-powered internal combustion engine capable of generating an exhaust gas flow; an exhaust aftertreatment system communicating with the diesel-fueled internal combustion engine to receive exhaust gas, the exhaust after-treatment system comprising a diesel particulate filter comprising a filter substrate for trapping particulate matter present in the exhaust gas flow; and a catcher disposed downstream of the diesel particulate filter and communicating with the diesel particulate filter so as to receive exhaust gas, the catcher comprising a generally tubular mesh screen through which flows all of the exhaust gas received by the catcher, the mesh screen having a plurality of of apertures sized to intercept sparks whose magnitude exceeds a threshold, the sparks being generated by the diesel-powered internal combustion engine and intercepting fragments of damaged components whose magnitude exceeds the threshold, the fragments of damaged components Parts of a damaged aftertreatment device, which is located upstream of the catcher. The exhaust aftertreatment system of claim 17, wherein the diesel-fueled internal combustion engine generates at least 50 Anglo-American horsepower. The exhaust after-treatment system of claim 18, wherein the diesel-fueled internal combustion engine generates at least 500 Anglo-American horsepower. The exhaust aftertreatment system of claim 17, wherein the diesel-fueled internal combustion engine and the exhaust aftertreatment system meet at least one of the exhaust emission standards. Tier 4 and Euro IIIb are enough.

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