Patent Publication Number: US-8974740-B2

Title: Exhaust treatment component mounting system

Description:
FIELD 
     The present disclosure relates to an exhaust treatment component mounting system. 
     BACKGROUND 
     This section provides background information related to the present disclosure which is not necessarily prior art. 
     Combustion engines are known to produce emissions that may be harmful to the environment. In an effort to decrease the environmental consequences that an engine may have, exhaust after-treatment systems have undergone extensive analysis and development. Various components that assist in treating engine emission include particulate filters and oxidation and reduction catalysts. 
     Over time, some of the various exhaust after-treatment elements may require removal and servicing. For example, in the case of a particulate filter, the particulate filter may need to be serviced after it builds up a certain amount of soot. One way of accomplishing this is to make the various after-treatment components removable from the assembly. 
     SUMMARY 
     This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
     The present disclosure provides an exhaust treatment component mounting system including an exhaust treatment component canister that includes a cleat ring, and an exhaust treatment component housing including a radially outwardly extending flange. A torsion rod including a first end that mates with the flange of the housing, and a second end including a coupling that mates with the cleat ring, wherein during connection between the first end and the second end of the torsion rod, the canister is rigidly secured to the housing. 
     Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       DRAWINGS 
       The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
         FIG. 1  is a schematic representation of an exhaust system according to a principle of the present disclosure; 
         FIG. 2  is a cross-sectional view of a first exhaust treatment component according to a principle of the present disclosure; 
         FIG. 3  is an exploded perspective view of the first exhaust treatment component illustrated in  FIG. 2 ; 
         FIG. 4  is a partial cross-sectional view of the first exhaust component illustrated in  FIG. 2 , including an exhaust treatment component mounting system according to a principle of the present disclosure; and 
         FIG. 5  is a partial front-perspective view of the exhaust treatment component mounting system of  FIG. 4 . 
     
    
    
     Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION 
     Example embodiments will now be described more fully with reference to the accompanying drawings. 
       FIG. 1  schematically illustrates an exhaust system  10  according to the present disclosure. Exhaust system  10  can include at least an engine  12  in communication with a fuel source  14  that, once consumed, will produce exhaust gases that are discharged into an exhaust passage  16  having an exhaust after-treatment system  18 . Downstream from engine  12  can be disposed a first exhaust treatment component  20 , which in the illustrated embodiment can include a diesel oxidation catalyst (DOC)  22 . A second exhaust treatment component  24  is coupled to first exhaust treatment component  20  by a coupling system  26 , as will be described in more detail below. Second exhaust treatment component can be a diesel particulate filer (DPF) component  28 . 
     Although not required by the present disclosure, exhaust after-treatment system  18  can further include components such as a thermal enhancement device or burner  30  to increase a temperature of the exhaust gases passing through exhaust passage  16 . Increasing the temperature of the exhaust gas is favorable to achieve light-off of the catalyst in the exhaust treatment component  20  in cold-weather conditions and upon start-up of engine  12 , as well as initiate regeneration of DPF  28 . 
     To further assist in reduction of the emissions produced by engine  12 , exhaust after-treatment system  18  can include a dosing module  32  for periodically dosing an exhaust treatment fluid into the exhaust stream. As illustrated in  FIG. 1 , dosing module  32  can be located upstream of a third exhaust treatment component  34 , and is operable to inject an exhaust treatment fluid into the exhaust stream. In the illustrated embodiment, third exhaust treatment component  34  is a selective catalytic reduction (SCR) component  36 . In this regard, dosing module  32  is in fluid communication with a reagent tank  38  and a pump  40  by way of inlet line  42  to dose an exhaust treatment fluid such as diesel fuel or urea into the exhaust passage  44  upstream of third exhaust treatment component  34 . Dosing module  32  can also be in communication with reagent tank  38  via return line  46 . Return line  46  allows for any exhaust treatment fluid not dosed into the exhaust stream to be returned to reagent tank  38 . Flow of the exhaust treatment fluid through inlet line  42 , dosing module  32 , and return line  46  also assists in cooling dosing module  32  so that dosing module  32  does not overheat. Although not illustrated in the drawings, dosing module  32  can be configured to include a cooling jacket that passes a coolant around dosing module  32  to cool it. 
     The amount of exhaust treatment fluid required to effectively treat the exhaust stream may vary with load, engine speed, exhaust gas temperature, exhaust gas flow, engine fuel injection timing, desired NO x  reduction, barometric pressure, relative humidity, EGR rate and engine coolant temperature. A NO x  sensor or meter  48  may be positioned downstream from SCR  34 . NO x  sensor  48  is operable to output a signal indicative of the exhaust NO x  content to an exhaust after-treatment system controller  50 . All or some of the engine operating parameters may be supplied from an engine control unit  52  via the engine/vehicle databus to exhaust after-treatment system controller  50 . The exhaust after-treatment system controller  50  could also be included as part of the engine control unit  52 , without departing from the scope of the present disclosure. Exhaust gas temperature, exhaust gas flow and exhaust back pressure and other vehicle operating parameters may be measured by respective sensors, as indicated in  FIG. 1 . 
     The amount of exhaust treatment fluid required to effectively treat the exhaust stream can also be dependent on the size of the engine  12 . In this regard, large-scale diesel engines used in locomotives, marine applications, and stationary applications can have exhaust flow rates that exceed the capacity of a single dosing module  32 . Accordingly, although only a single dosing module  32  is illustrated for urea dosing, it should be understood that multiple dosing modules  32  for urea injection are contemplated by the present disclosure. 
     Now referring to  FIGS. 2-5 , first exhaust treatment component  20  can include a cylindrically-shaped housing  54 . At a first end  56  of housing  54  can be attached an exhaust inlet  58 . Exhaust inlet  58  can be conically-shaped, and can include at attachment ring  60  that can be bolted or fastened to an end of exhaust passage  16 . Exhaust inlet  58  can be secured to first end  56  of housing  54  by welding, by using a clamp (not shown), or by any other attachment method known to one skilled in the art. 
     Second exhaust treatment component  24  can include a cylindrically-shaped canister  62 . At a second end  64  of canister  62  can be attached an exhaust outlet  66 . Similar to exhaust inlet  58 , exhaust outlet  66  can be conically-shaped, and can include at attachment ring  68  that can be bolted or fastened to an end of exhaust passage  44 . Exhaust outlet  66  can be secured to second end  64  of canister  62  by welding, by using a clamp (not shown), or by any other attachment method known to one skilled in the art. 
     First exhaust treatment component  20  houses a substrate brick  70 . Because first exhaust treatment component  20  houses DOC  22 , substrate brick  70  can be catalyst-coated to achieve oxidation of the exhaust gases passing therethrough. Second exhaust treatment component  24  also houses a substrate brick  72 . Because second exhaust treatment component  24  houses DPF  28 , substrate brick  72  can be a filter that is operable to filter soot and other particulate matter from the exhaust stream. Although exhaust treatment components  20  and  24  are illustrated as having a DOC  22  and DPF  28 , respectively, the present disclosure should not be limited thereto. In this regard, exhaust treatment components  20  and  24  can house any combination of a DOC, DPF, SCR, lean NO x  catalyst (LNC), ammonia slip catalyst, and the like. An insulating mat  74  can be disposed between bricks  70  and  72  and housing  54  and canister  62 , respectively. Mat  74  prevents heat in exhaust treatment component  20  and  24  from escaping housing  54  and canister  62  so that the catalysts of DOC  22  and SCR  36  can remain at light-off temperature. 
     Housing  54  extends axially in a direction from exhaust inlet  58  toward exhaust outlet  66  of exhaust treatment components  20  and  24 , respectively. At a position between first end  56  and a second end  76  of housing  54  can be disposed a radially outwardly extending flange  78 . Flange  78  can extend about an entire circumference of housing  54 , or be disposed intermittently at various positions about the circumference of housing  54 . Flange  78  can include an aperture  80  for securing a tension rod assembly  82  of coupling system  26 , as will be described in more detail later. Second end  76  of housing  54  can terminate at an L-shaped first gasket flange  84 . First gasket flange  84  is designed to provide a sealing surface for a gasket  86  that can be disposed between housing  54  and canister  62  of exhaust treatment component  24 . 
     At a first end  88  of canister  62  can be formed a second gasket flange  90  that mates with first gasket flange  84  with gasket  86  therebetween. Second gasket flange  90  extends radially outward relative to canister  62 . As shown in  FIG. 4 , second gasket flange  90  extends radially outwardly relative to canister  62  to a lesser extent than first gasket flange  84  extends radially outwardly relative to housing  54 . In addition, first gasket flange  84  includes an axial component or circumferentially extending lip  92  that receives second gasket flange  90  with gasket  86  therebetween. Axial component  92  ensures that gasket  86  remains tightly secured between first and second gasket flanges  84  and  90 . To secure gasket  86  between first and second gasket flanges  84  and  90 , gasket  86  includes a gasket pilot ring  94  that extends axially relative to gasket  86 . During assembly of exhaust treatment component  24  into annular housing  54 , gasket pilot ring  94  including gasket  86  can first be seated against first gasket flange  84 , and then canister  62  including second gasket flange  90  can be inserted to abut against gasket  86  and first gasket flange  84 . 
     At a location between first end  88  and second end  64  of canister  62  can be disposed a cleat ring  96 . Cleat ring  96  can extend about an entire circumference of canister  62 , and may be fixed to canister  62  by welding, brazing, or any other attachment method known to one skilled in the art. As best shown in  FIG. 4 , cleat ring  96  extends radially outwardly relative to canister  62 , and includes a radius of curvature  98  in the axial direction. 
     To secure canister  62  to housing  54 , coupling system  26  including tension rod assembly  82  can be used. Tension rod assembly  82  includes first rod or male component  100  and a second rod or female component  102 . Male component  100  can be in the form of a threaded bolt having a threaded shank portion  104  and a head portion  106 . A retainer  108  includes a through-hole  110  formed in a base portion thereof in receipt of shank portion  104 . Head portion  106  is restricted from passing through hole  110  thereby coupling one end of first rod  100  to retainer  108 . Retainer  108  has a radius of curvature at an angled finger portion  112  that corresponds to that of cleat ring  96 . 
     Female component  102  includes a threaded recess  114  for accepting and mating with threaded shank portion  104 . At an end of female component  102  opposite to threaded recess  114 , female component  102  can include a hemispherical-shaped bulb  116 . Bulb  116  allows tension rod  82  to rotate away from canister  62  during insertion and removal of canister  62  from housing  54 . Female component  102  is designed to feed through aperture  80  of flange  78 , with bulb  116  having a diameter that is greater than that of aperture  80  that prevents female component  102  from feeding entirely through aperture  80 , thereby coupling one end of second rod  102  to flange  78 . 
     To secure first and second exhaust treatment components  20  and  24  together using mounting system  26 , gasket pilot ring  94  including gasket  86  may first be seated against first gasket flange  84 . Then, canister  62  may be mated with housing  54  such that gasket  86  is positioned between first and second gasket flanges  84  and  90 . Female component  102  may then be fed through aperture  80 , retainer  108  may be disposed about male component  100 , and male component  100  mated with female component  102 . As male component  100  is mated with female component  102 , retainer  108  should be oriented to mate with cleat ring  86 . As male component  100  is further tightened, the mating between coupling  108  and cleat ring  96  will pull canister  62  toward housing  54  to further compress gasket  86 , which results in a hermetic seal between canister  62  and housing  54 . 
     During tightening of male component  100  relative to female component  102 , bulb  116  may be inclined to rotate in aperture  80 . To prevent rotation of bulb  116  relative to aperture  80 , bulb  116  may include an anti-rotation feature  118  that abuts flange  80 . Anti-rotation feature  118  can be a notched portion formed in bulb  116 . Outward from anti-rotation feature  118 , however, bulb  116  should be a curved hemispherical surface to allow tension rod  82  to rotate relative to canister  62  during removal of canister  62  from annular housing  54 , as shown in phantom in  FIG. 4 . 
     More particularly, during removal of canister  62  from housing  54 , coupling system  26  is designed to allow for rotation (arrow  120 ) of tension rod  82  relative to canister  62  that allows for easier removal of canister  62  from housing  54 . In this regard, as male component  100  is untightened from female component  102 , the mating force between retainer  108  and cleat ring  96  will be removed. Once retainer  108  can be disengaged from cleat ring  96 , tension rod  82  and retainer  108  can be rotated away from canister  62  to allow canister  62  to be gripped at cleat ring  96  and pulled outward from housing  54 . 
     The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.