Exhaust aftertreatment sensor assembly

An exhaust aftertreatment system includes an exhaust aftertreatment component housing and a sensor table coupled to an exterior surface of the exhaust aftertreatment component housing. The sensor table includes a base including footings and a first platform offset from the footings by first standoffs so to define a first air gap. The base also includes second standoffs extending from the first platform. The sensor table also includes a top plate including a second platform and third standoffs extending from the second platform. The second platform is fixedly coupled to the second standoffs so to define a second air gap between the first platform and the second platform. The sensor table further includes a first sensor module coupled to the third standoffs so to define a third air gap between the second platform and the first sensor module.

BACKGROUND

Exhaust aftertreatment systems receive and treat exhaust gas generated from an internal combustion (IC) engine. Typical exhaust aftertreatment systems include any of various components configured to reduce the level of harmful exhaust emissions present in the exhaust gas. For example, some exhaust aftertreatment systems for IC engines, such as diesel-powered IC engines, include various components, such as a diesel oxidation catalyst (DOC), particulate matter filter or diesel particulate filter (DPF), and a selective catalytic reduction (SCR) catalyst, among others. In some exhaust aftertreatment systems, exhaust gas first passes through the diesel oxidation catalyst, then passes through the diesel particulate filter, and subsequently passes through the SCR catalyst.

Each of the DOC, DPF, and SCR catalyst components is configured to perform a particular exhaust emissions treatment operation on the exhaust gas passing through the components. Generally, the DOC reduces the amount of carbon monoxide and hydrocarbons present in the exhaust gas via oxidation techniques. The DPF filters harmful diesel particulate matter and soot present in the exhaust gas. Finally, the SCR catalyst reduces the amount of nitrogen oxides (NOx) present in the exhaust gas.

One or more exhaust aftertreatment components, such as the DOC, DPF, and SCR catalyst can be housed in a common housing in an end-to-end or end-to-side configuration. Exhaust aftertreatment components may be controlled based on detected operating conditions to facilitate optimal exhaust emissions treatment. Typically, the operating conditions include exhaust gas conditions that are detected by one or more sensors in fluid communication with the exhaust gas passing through the exhaust aftertreatment system. The sensors may be electrically coupled to one or more modules that process and transmit data associated with the signals received from the sensors. For example, a conventional exhaust aftertreatment system may include exhaust temperature sensors to detect the temperature of exhaust gas at various locations within the system, exhaust pressure sensors to detect the pressure of exhaust gas at various locations within the system, NOxsensors to detect the concentration of NOxin the exhaust gas at various locations within the system, and ammonia (NH3) sensors to detect the concentration of ammonia in the exhaust gas at various locations within the system. The sensors and associated modules are commonly mounted onto an exterior of the housing that contains the exhaust aftertreatment components.

Conventional aftertreatment component sensors and modules are susceptible to degradation and failure due to exposure to excessive heat and vibration. Heat from the exhaust gas flowing through the exhaust aftertreatment components tends to transfer from the exhaust gas, through the housing, and into the sensors and modules via conduction and convention. Further, the sensors and modules may vibrate during operation of the engine due to vibrations induced by the engine and/or by a vehicle in which the engine is housed. Although some heat transfer and/or vibrations may be tolerable, excessive heat transfer and/or vibrations may result in fault codes, vehicle down time, and higher costs.

SUMMARY

One embodiment relates to an exhaust aftertreatment system. The exhaust aftertreatment system includes an exhaust aftertreatment component housing and a sensor table coupled to an exterior surface of the exhaust aftertreatment component housing. The sensor table includes a base including footings and a first platform offset from the footings by first standoffs so to define a first air gap. The base also includes second standoffs extending from the first platform. The sensor table also includes a top plate including a second platform and third standoffs extending from the second platform. The second platform is fixedly coupled to the second standoffs so to define a second air gap between the first platform and the second platform. The sensor table further includes a first sensor module coupled to the third standoffs so to define a third air gap between the second platform and the first sensor module.

Another embodiment relates to an exhaust aftertreatment system. The exhaust aftertreatment system includes a first exhaust aftertreatment component and a second exhaust aftertreatment component in fluid communication with the first exhaust aftertreatment component. The first and second exhaust aftertreatment components are arranged in a switch-back configuration. The exhaust aftertreatment system also includes a first sensor table coupled to a housing of the first exhaust aftertreatment component via a remote mounting bracket. The remote mounting bracket is configured to provide a space between the first sensor table and the housing. The exhaust aftertreatment system further includes a first sensor assembly mounted to the first sensor table.

DETAILED DESCRIPTION

The subject matter of the present application has been developed in response to the present state of the art and, in particular, in response to the problems and needs in the art that have not yet been fully solved by currently available exhaust aftertreatment systems employing exhaust condition sensors. Accordingly, the subject matter of the present application has been developed to provide an exhaust sensor assembly and associated apparatus that overcome at least some of the above-mentioned and below-mentioned shortcomings of prior art exhaust aftertreatment systems and exhaust condition sensing techniques and devices.

Certain types of vehicles, such as heavy-duty trucks powered by diesel engines, may operate both in transit and while stationary. For example, certain types of vehicles may spend a significant amount of operational time (e.g., up to 90%) with the engine running while the vehicle is stationary. For example, the engine may be running a generator to cool a refrigerated truck, to drive a pump on a fire engine, to power hydraulics for a crane or construction equipment, etc. Stationary applications often provide worst-case heat conditions due to the lack of cool ambient airflow.

The number of exhaust aftertreatment components utilized in diesel-powered vehicles has increased as increasingly stringent exhaust emissions requirements have been implemented. In addition, the amount of available space on vehicles to mount exhaust aftertreatment components is limited. Therefore, as manufacturers implement additional exhaust aftertreatment components, such components often must be arranged in close proximity to each other, and in close proximity to other vehicle components. As such, exhaust aftertreatment components are likely to receive heat from and to transfer heat to other vehicle components. Such heating, combined with the lack of cool ambient airflow in stationary applications, may cause dangerously hot operating conditions compared to conventional exhaust aftertreatment systems. Electronic components, such as sensor assemblies utilized with exhaust aftertreatment systems, may become damaged if exposed to excessive heat over time. Therefore, it is desirable to minimize heat transfer from vehicle components, such as exhaust aftertreatment components, to their corresponding sensor assemblies.

FIG. 1illustrates an exhaust aftertreatment system100configured to reduce exhaust emissions from an IC engine (e.g., a diesel engine), according to an example embodiment. The exhaust aftertreatment system100includes a housing102in fluid (e.g., exhaust gas) communication with an IC engine. The exhaust aftertreatment system100includes a plurality of exhaust treatment devices or components retained within the housing102. In an example embodiment, the exhaust aftertreatment system100includes a diesel particulate filter (DPF) retained within the housing102. In another example embodiment, retained within the housing102, the exhaust aftertreatment system100includes a diesel oxidation catalyst (DOC) and a DPF downstream of the DOC. In another example embodiment, the aftertreatment system100includes a selective catalytic reduction (SCR) catalyst retained within the housing102downstream of the DPF (see, e.g.,FIG. 8). Although the exhaust aftertreatment system100ofFIG. 1includes one DOC and DPF in a specific order relative to each other, in other embodiments, exhaust aftertreatment systems can have fewer or additional exhaust aftertreatment devices, which may be in the same order of in a different order as those of the exhaust aftertreatment system100without departing from the essence of the present disclosure.

The exhaust aftertreatment system100also includes a sensor assembly104mounted on a two-part sensor table106, which is coupled to the housing102. As shown, the sensor table106is coupled to an exterior surface of the housing102via a band108. In other example embodiments, the sensor table106is coupled to the housing102in other ways, such as by welding or otherwise fastening the sensor table106to the housing102. In some example embodiments, the exhaust aftertreatment system100also includes an insulating cover109positioned on an exterior surface of the housing102to retain heat within the housing102. In some embodiments including a cover109, the sensor table106is mounted directly to the cover109, which is attached to the housing102. However, in other embodiments, the sensor table106is mounted directly to the housing102via openings in the cover109.

According to various example embodiments and as explained in further detail below, the sensor table106includes various design features to minimize heat transfer and vibration to the sensor assembly104. For example, the sensor table106in one embodiment includes various design features (e.g., standoffs) that define multiple air gaps to minimize heat transfer from the housing102to the sensor assembly104by providing air insulation layers and air flow channels therebetween. In addition, the overall shape of the sensor table106is optimized to minimize conductive heat transfer from the housing102to the sensor assembly104. Further, the sensor table106includes ribs to provide improved structural strength, thereby optimizing resistance to vibration-induced stress and strain.

FIG. 2is an exploded view of the sensor assembly104and the sensor table106ofFIG. 1. The sensor table106is a two-part structure including a base110and a top plate112fixedly coupled to the base via welding (e.g., spot welding), adhesion, fastening techniques, etc. In an example embodiment, each of the base110and the top plate112are formed of sheet metal, such as steel or aluminum, which is stamped and/or bent to form the geometry shown inFIG. 2. In other example embodiments, at least one of the base110and the top plate112are formed of various types of polymer materials, such as injection molded plastic.

The base110includes footings114that are configured to sit flush against an exterior of the housing102(FIG. 1). Accordingly, the footings114may have curved surfaces that match the curvature of the exterior surface of the housing102. The footings114are coupled to a first platform116by first standoffs118that extend substantially perpendicular from the footings114(e.g., transversely relative to the footings114) to offset the first platform116from the footings114and, accordingly, to offset the first platform116from the housing102. The space by which the first platform116is offset from the housing102defines a first air gap, as discussed further in connection withFIG. 3B. Moreover, when retained against an exterior surface of the housing102or cover109, the first air gap is further defined by the exterior surface of the housing102or cover109, such that the first air gap becomes an air flow channel with substantially enclosed sides and open ends. According to an example embodiment, the base110is substantially symmetrical, such that the base110includes two footings114. The footings114and the first standoffs118define first apertures120through which the band108ofFIG. 1may be threaded to secure the sensor table106to the housing102. In the example embodiment as depicted inFIG. 2, tightening of the band108is the primary means of securely retaining the sensor assembly104on the housing102.

The base110also includes a plurality of second standoffs122extending from the first platform116. The second standoffs122may comprise elevated surfaces or protrusions that extend above the surface of the first platform116. As shown inFIG. 2, the second standoffs122are positioned proximate the outer periphery of the first platform116and near the corners of the first platform116.

The top plate112is fixedly coupled to the base110via welding (e.g., spot welding), adhesion, and/or other fastening techniques. The top plate112includes a second platform124that is secured to the second standoffs122of the base110. The second standoffs122offset the second platform124from the first platform116so to define a second air gap, as discussed further in connection withFIG. 3B. The second air gap provides yet another air flow channel between the first and second platforms116,124with substantially open sides and ends. In some embodiments, the second platform124includes second apertures126sized, shaped, and positioned to be alignable with the second standoffs122. In an example embodiment, the top plate112is positioned on the base110such that the apertures120are aligned with the second standoffs122, which are spot welded to the second platform124of the top plate112via the second apertures126. In another example embodiment, fasteners extend through the second apertures126and through the second standoffs122to couple the top plate112to the base110. According to an example embodiment, the second standoffs122are integral to the top plate112and are formed by stamping. In another example embodiment, the second standoffs122comprise discrete spacers that are not integrally formed with the top plate112.

The top plate112also includes sidewalls128that extend substantially perpendicular relative to the second platform124, such that the top plate112is generally U-shaped. In an example embodiment, one or more sensors are mounted to one or both of the sidewalls128. Similar to the base110, the top plate112includes third standoffs130extending from the second platform124. The third standoffs130may be elevated regions or protrusions that extend above the surface of the second platform124. In an example embodiment, as shown inFIG. 2, the third standoffs130can be positioned at a central location of the second platform124. In another example embodiment, the third standoffs130can be located at any of various other locations on the second platform124, such near an outer periphery of the second platform124. The third standoffs130are configured to offset one or more sensors from the second platform124so to define a third air gap, as discussed further in connection withFIG. 3B. The top plate112may further include a fourth standoff132configured to offset sensor cables134(e.g., wires or leads) from the second platform124.

The sensor assembly104includes the temperature sensor module136(e.g., an exhaust gas temperature sensor module), a pressure differential sensor module138, and a delegated assembly harness140(e.g., customer connection harness). In an example embodiment, the third standoffs130are configured to receive and secure in place the temperature sensor module136of the sensor assembly104. The temperature sensor module130may include a housing that contains software and/or hardware logic to receive, process, and transmit data related to the signals received by the various temperature sensors142of the sensor assembly104. For example, the temperature sensor module130is electrically coupled to a plurality of exhaust temperature sensors142via the sensor cables134, which themselves can be secured by couplings, such as P-clamps144, elevated above the second platform124by the fourth standoffs132. With the temperature sensor module136secured to the third standoffs, the temperature sensor module136is raised above or spaced apart from the second platform124. In this manner, the third air gap is defined between the second platform124and the temperature sensor module136. The third air gap provides another air flow channel between the second platform124and the temperature sensor module136with substantially open sides and ends.

One or more sensors may be mounted to the sidewalls128of the top plate112. In an example embodiment, the pressure differential sensor module138is mounted to the one of the sidewalls128. The pressure differential sensor module138may include a housing that contains software and/or hardware logic to receive, process, and transmit data related to the signals received by the various pressure sensors of the sensor assembly104. For example, the pressure differential sensor module138may be mounted to the sidewall128via fasteners (e.g., bolts or screws), adhesives, or other fastening techniques. According to an example embodiment, the delegated assembly harness140is mounted to the top plate112via a clamp144.

Each of the base110and the top plate112are designed to provide optimal resistance to vibration-induced stress and strain. The geometry of the base110and the top plate112are optimized through extensive finite element analysis (FEA) and component testing (e.g., vibration shaker table testing). Geometric discontinuities such as sharp corners can cause stress concentrations. However, designing parts to minimize geometric discontinuities typically involves increased material usage, thereby increasing material cost and part size. Therefore, the apertures and radii of each of the corners and edges of each of the base110and the top plate112are optimized with respect to the particular material thickness (e.g., sheet metal thickness) of the respective base110and top plate112. Structural ribs146are also designed into each of the base110and the top plate112. In particular, the size, shape, and quantity of the structural ribs146are optimized through FEA and component testing. For example, in an example embodiment, the top plate112includes a plurality of structural ribs146traversing the intersection between the second platform124and the sidewalls128. The structural ribs146act to stabilize the sidewalls128relative to the second platform124such that relative movement between the sidewalls128and second platform124is reduced. Additionally structural ribs146may be included to couple two sections (e.g., an upper and lower section) of a single sidewall128as shown inFIG. 2. Similarly, the footings114of the base110include a structural ribs154that increase the rigidity of the footings114, which results in a reduction in vibrations. In addition, the quantity and position of the coupling interfaces between the base110and the top plate112are optimized. For example, according to an example embodiment, four plug welds are used to couple the base110and the top plate112.

FIG. 3Ais a front view of the exhaust aftertreatment system100ofFIG. 1, including the housing102and the sensor assembly104mounted to the housing102via the sensor table106.FIG. 3Bis a sectional view of the exhaust aftertreatment system100ofFIG. 3A, taken along line3B-3B. As explained above in connection withFIG. 2, the base110may be coupled to the housing102over the cover109. The first platform116of the base110is offset from the housing102(e.g., including the cover109) via the standoffs118, thereby defining a first air gap148between the first platform116and the housing102. The second platform124of the top plate112is offset from the first platform116via the second standoffs122, thereby defining a second air gap150between the first platform116and the second platform124. The temperature sensor module136is offset from the second platform124via the third standoffs130, thereby defining a third air gap152between the second platform124and the temperature sensor module136. Temperature is typically hottest near the housing102. Therefore, according to an example embodiment, the first air gap148is the largest of the first, second, and third air gaps148,150,152so as to facilitate a significant temperature reduction immediately adjacent the housing102. Similarly, temperature is typically hotter at the second air gap150versus the third air gap152. Therefore, according to an example embodiment, the second air gap150is larger than the third air gap152.

The first, second, and third air gaps148,150,152facilitate the flow of ambient air154external to the housing102, and between and around the housing102, the first platform116, the second platform124, and the temperature sensor module136. In operation, heat from exhaust gas flowing through the housing102is transferred to the housing102. Heat from the housing102tends to transfer to the base110via conduction, as well as convection. Likewise, heat from the base110tends to transfer to the top plate112via conduction and convection. Similarly, heat from the top plate112tends to transfer to the temperature sensor module136via conduction and convection. Air located within the first, second, and third air gaps148,150,152acts as layers of insulation to reduce heat transfer between the housing102, the base110, the top plate112, and the temperature sensor module136. Further, because the temperature of ambient air is typically less than the temperature of each of the housing102, the base110, the top plate112, and the temperature sensor module136during operation, ambient air flow through the first, second, and third air gaps148,150,152facilitates heat transfer from each of the housing102, the base110, the top plate112, and the temperature sensor module136to the moving air via convection. The heated air then flows back into the environment where the heat is dissipated. In this manner, the first, second, and third air gaps148,150,152reduce heat transfer from the exhaust gas and the housing102to each of the base110, the top plate112, and the temperature sensor module136, and increase the heat transfer away from each of the base110, the top plate112, and the temperature sensor module136. Additionally, the relative large flat surface area of each of the first and second platforms116,124promotes conductive and convective heat transfer away from the base110and top plate112, and thereby the sensor modules, and into the ambient air flow154.

The overall reduction in heat transfer to each of the temperature sensor module136, the pressure differential sensor module138, and the delegated assembly harness140, by virtue of less heat transfer to the top plate112, improves the operating lifecycle of the sensor assembly104and the associated sensors, thereby reducing fault codes, vehicle down time, and operating cost. Further, the configuration of the sensor assembly104promotes easy access to the delegated assembly harness140.

FIG. 4is a top view of the sensor assembly104and the sensor table106ofFIGS. 1-3B. In some embodiments, such as the example embodiment illustrated inFIG. 4, a heat shield156is secured to the sidewalls128of the top plate112to further minimize heat transfer to the sensor assembly104. In some embodiments, the heat shield156may be utilized in applications in which an external heat source is positioned near the sensor assembly104. In addition to insulating the sensor assembly104from heat, the heat shield156also protects the sensor assembly104from debris.

FIG. 5illustrates an exhaust aftertreatment system200according to another example embodiment. Generally, the exhaust aftertreatment system200is similar to the exhaust aftertreatment system100ofFIGS. 1-4. Similar to the exhaust aftertreatment system100, the exhaust aftertreatment system200includes a housing202and a sensor assembly204mounted on a two-part sensor table206, which is coupled to the housing202. However, according to an example embodiment, the housing202of the exhaust aftertreatment system200is configured to receive and house an SCR catalyst, whereas the housing102of the exhaust aftertreatment system100ofFIGS. 1-4is configured to house a DPF and/or a DOC. Accordingly, the sensor assembly204includes sensors and sensor modules associated with operation of an SCR catalyst. The sensor table206is coupled to the external surface of the housing202via bands208. However, in other example embodiments, the sensor table206is coupled to the external surface of the housing202via welds, fasteners, or other fastening techniques. In some example embodiments, an insulating cover209is positioned on the external surface of the housing202.

FIG. 6is an exploded view of the sensor assembly204and the sensor table206ofFIG. 5. The sensor table206is a two-part structure including a base210and a top plate212fixedly coupled to the base via welding (e.g., spot welding), adhesion, fastening techniques, etc. In an example embodiment, each of the base210and the top plate212are formed of sheet metal, such as steel or aluminum, which is stamped and/or bent to form the geometry shown inFIG. 6. In other example embodiments, at least one of the base210and the top plate212are formed of various types of polymer materials, such as injection molded plastic.

The base210and the top plate212are elongated relative to the base110and top plate112ofFIGS. 1-4to accommodate the additional SCR-related components of the sensor assembly204. The base210, due to its elongation, includes two pairs of footings214coupled to the housing202via respective bands208. The footings214are coupled to a first platform216by first standoffs218that extend substantially perpendicular from the footings214to offset the first platform216from the footings214and, accordingly, to offset the first platform216from the housing202. The space by which the first platform216is offset from the housing202defines a first air gap. The base210also includes a plurality of second standoffs220extending from the first platform216. The second standoffs220may comprise elevated surfaces or protrusions that extend above the surface of the first platform216.

The top plate212is fixedly coupled to the base210via welding (e.g., spot welding), adhesion, and/or other fastening techniques. The top plate212includes a second platform222that is secured to the second standoffs220of the base210. The second standoffs220offset the second platform222from the first platform216so to define a second air gap. In some embodiments, the second platform222includes second apertures224to facilitate coupling of the top plate212to the base210, for example, via spot welding. According to an example embodiment, the top plate212also includes brackets226that are bent to extend substantially perpendicular from the second platform222to abut the first standoffs218of the base210. The brackets226may also include second apertures224to facilitate coupling of the top plate212to the base210. The top plate212also includes third standoffs228extending from the second platform222. The third standoffs228are configured to offset one or more sensors from the second platform222so to define a third air gap. The sensor assembly204includes a NOxsensor module230, a mid-bed NH3sensor module232, a temperature sensor module234(e.g., an exhaust gas temperature sensor module), and a delegated assembly harness236(e.g., customer connection harness).

FIG. 7Ais a front view of the exhaust aftertreatment system200ofFIG. 6, including the housing202and the sensor assembly204mounted to the housing202via the sensor table206.FIG. 7Bis a sectional view of the exhaust aftertreatment system200ofFIG. 7A, taken along line7B-7B. The first platform216of the base210is offset from the housing202(e.g., including the cover209) via the standoffs218, thereby defining a first air gap238between the first platform216and the housing202. The second platform222of the top plate212is offset from the first platform216via the second standoffs220, thereby defining a second air gap240between the first platform216and the second platform222. The NOxsensor module230, for example, is offset from the second platform222via the third standoffs228, thereby defining a third air gap242between the second platform222and the NOxsensor module230.

As with the sensor assembly104and the sensor table106ofFIGS. 1-4, the first, second, and third air gaps238,240,242reduce heat transfer from the housing202to each of the base210, the top plate212, and the sensor assembly204. Further, the first, second, and third air gaps238,240,242increase the heat transfer away from each of the base210, the top plate212, and the sensor assembly204. Additionally, the relatively large flat surface area of the first and second platforms216,222promotes conductive heat transfer away from the base210and the top plate212, and thereby away from the sensor assembly204.

FIG. 8illustrates an exhaust aftertreatment system300according to another example embodiment. Generally, the exhaust aftertreatment system300is similar to the exhaust aftertreatment systems100and200ofFIGS. 1-7B. The exhaust aftertreatment system300includes a first housing302and a first sensor assembly304mounted on a remote-mount sensor table306, which is coupled to the first housing302via a band308. The exhaust aftertreatment system300also includes a second housing310in fluid communication with the first housing302and positioned substantially below the first housing302. For the purposes of this disclosure, relative terms such as “above,” are used herein with respect to the position of components as they are depicted in the figures and/or as they would be mounted in a vehicle, which is in accordance with common usage by those of ordinary skill in the art. In an example embodiment, the first housing302includes a DPF and/or a DOC and the second housing310includes an SCR catalyst. The configuration of the exhaust aftertreatment system300may be referred to as a “switchback configuration” because after flowing in a first direction through the first housing302, the exhaust gas is routed in a second direction through a conduit coupling the first and second housings302,310, where the exhaust gas subsequently flows in the first direction through the second housing310.

FIG. 9Aillustrates conventional mounting configurations for components of exhaust aftertreatment systems similar to the exhaust aftertreatment system300ofFIG. 8. According to an example embodiment, the first sensor assembly304is mounted to the first housing302and a second sensor assembly312is mounted to the second housing310. The first sensor assembly304is a DPF sensor assembly and the first housing302includes a DPF, and the second sensor assembly312is an SCR sensor assembly and the second housing310includes an SCR catalyst.

FIG. 9Billustrates the mounting configuration of the exhaust aftertreatment system300ofFIG. 8, according to an example embodiment. In an example embodiment, the first housing302including a DPF and/or a DOC is positioned substantially above the second housing310including an SCR catalyst. As shown inFIG. 9B, the first and second housings302,310are mounted in a switchback configuration within a step box314. Such a space may have poor airflow characteristics, especially during stationary operations (e.g., power generation), which may lead to excessive heat buildup. In particular, a first side316of the exhaust aftertreatment system300is generally enclosed by the step box314, whereas a second side318of the step box314is generally open, or at least more open than the first side316. Because of the enclosed space and poor airflow of the first side316, more heat tends to build up on the first side316as compared to the second side318. Therefore, in an example embodiment, the second sensor assembly312is mounted on the first housing302so as to be proximate the second side318rather than on the second housing310, and the first sensor assembly304is mounted further from the first housing302via the remote-mount sensor table306. The remote-mount sensor table306is configured to increase the space between the first sensor assembly304and the first housing302. The increase in space effectively increases the amount of insulation provided by the air between the first sensor assembly304and the first housing302, thereby decreasing heat transfer from the first housing302to the first sensor assembly304. The second sensor assembly312is mounted to the first housing302via a second sensor table320. In an example embodiment, the second sensor table320is the same as or similar to the sensor table206ofFIGS. 5-7B.

The remote-mount sensor table306is mounted to the first housing302via a remote mounting bracket322. The remote mounting bracket322includes two spaced-apart legs324,326that diverge away from the first sensor assembly304towards the first housing302. In other words, the legs324,326generally form a V-shape. As shown inFIG. 8, each of the legs324,326includes a footing328that sits flush against the first housing302, and an aperture330formed proximate the footing328. A band332extends through the apertures330in the legs324,326. The band332can be tightened against the footings328to securely retain the remote mounting bracket322, and therefore the remote-mount sensor table306, to an exterior of the first housing302. The legs324,326are shaped and sized such that when securely coupled to the first housing302, the first sensor assembly304is spaced away from the exterior of the first housing302by a desired distance. In an example embodiment, the desired distance is between about 0.5 and 1.5 times a radius of the first housing302.

FIG. 10is an exploded view of the first sensor assembly304and the remote-mount sensor table306ofFIGS. 8 and 9B. The first sensor assembly304includes a pressure differential sensor module334and a temperature sensor module336. The pressure differential sensor module334is operably coupled to pressure sensor probes338via first cables340and is configured to measure pressure levels of the exhaust gas within the first housing302. In particular, the pressure differential sensor module334is configured to measure a pressure drop across an exhaust aftertreatment component (e.g., a DPF) within the first housing302. The temperature sensor module336is operably coupled to temperature probes342via second cables344and is configured to measure temperature levels of the exhaust gas within the first housing302. Each of the pressure differential sensor module334and the temperature sensor module336is mounted to the sensor mounting bracket346. The sensor mounting bracket346is mounted within a heat shield348. The heat shield348provides additional protection against heat transfer from the first housing302and the surrounding components, and further protects the first sensor assembly304from debris. The heat shield348is mounted on the remote mounting bracket322to complete the remote-mount sensor table306, thereby mounting the first sensor assembly304to the first housing302.

FIG. 11Aillustrates another conventional mounting configuration for exhaust aftertreatment components and corresponding sensor assemblies. Certain Original Equipment Manufacturers (OEMs) may position exhaust aftertreatment components in different configurations. For example, as shown in the configuration ofFIG. 11A, a first housing402including an SCR catalyst is positioned substantially above a second housing404including a DPF and/or a DOC. A first sensor assembly406is mounted on the first housing402and a second sensor assembly408is mounted on the second housing404. However, heat from each of the first and second housings402,404and from the surrounding components may be transferred to the first and second sensor assemblies406,408, which may induce thermal stress-related failures.

FIG. 11Billustrates an alternative mounting configuration for the first and second sensor assemblies406,408ofFIG. 11A. In the example embodiment shown inFIG. 11B, the first sensor assembly406is mounted to the first housing402via a first remote-mount sensor table410, and the second sensor assembly408is mounted to the second housing404via a second remote-mount sensor table412coupled to a remote mounting bracket414. Each of the first and the second remote-mount sensor tables410,412are configured to provide additional space between the respective first and second sensor assemblies406,408to minimize heat transfer to the respective sensor assemblies. According to an example embodiment, the first sensor assembly406is an SCR sensor assembly and the first housing402includes an SCR catalyst. In addition, the second sensor assembly408is a DPF sensor assembly and the second housing404includes a DPF.

While various embodiments of the disclosure have been shown and described, it is understood that these embodiments are not limited thereto. The embodiments may be changed, modified and further applied by those skilled in the art. Therefore, these embodiments are not limited to the detail shown and described previously, but also include all such changes and modifications.