Abstract:
An exhaust after-treatment mounting arrangement is provided that is mounted outside of an engine compartment and has a perforated enclosure allowing air to permeate the enclosure and establish an airflow through the enclosure to maintain part integrity of components of an exhaust after-treatment system with maximum temperature thresholds. Components of the exhaust after-treatment system may be mounted to permit movement of such components relative to upstream and downstream components in the exhaust system. The enclosure is configured to prevent contact of the hot components by operators and/or flammable materials with small venting holes through top surfaces of the enclosure and large vent holes in bottom areas of the box that allow large volumes of air to easily flow into the enclosure.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a non-provisional application based upon U.S. provisional patent application Ser. No. 62/153,807, entitled “Exhaust After-treatment Mounting Arrangement,” filed Apr. 28, 2015, which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates generally to off-road agricultural vehicles with exhaust after-treatment systems and in particular, to an exhaust after-treatment mounting arrangement. 
       BACKGROUND OF THE INVENTION 
       [0003]    Exhaust after-treatment components are needed for many diesel engines to comply with emissions requirements. These after-treatment components can be huge, making them difficult to incorporate into an engine compartment. Some after-treatment components produce a great amount of heat at times during operation, such as during regeneration cycles. 
       SUMMARY OF THE INVENTION 
       [0004]    An exhaust after-treatment mounting arrangement is provided that mounts all of the exhaust after-treatment components in a single box that prevents contact of the hot components by operators and/or flammable materials. This may be done with small venting holes through top surfaces of the box making these surfaces access restricting shielding surfaces and large vent holes in bottom areas of the box that facilitates drawing air into the box so that the box does not require forced air for cooling. The box is arranged outside of the engine compartment with the exhaust after-treatment components flexibly mounted to upstream and downstream exhaust tubing. 
         [0005]    According to one aspect of invention, the exhaust after-treatment components are mounted in an enclosure that has different surfaces with different sized openings to restrict penetrability by operators and/or flammable materials through relatively exposed surfaces. This may be done by configuring the enclosure with relatively small venting holes at easily accessible exposed surfaces. The relatively small venting holes allow sufficient air permeability to maintain acceptable temperatures in an interior of the enclosure while blocking inadvertent operator contact of the hot exhaust after-treatment components. The relatively small venting holes are small enough to be substantially impenetrable by flammable materials that are encountered during use such as field debris and/or other flammable airborne particulates and materials. Large openings at less accessible surfaces of the enclosure allow for high flow rates of air through the enclosure and provide debris releasing openings at the bottom as a substantially open bottom that minimizes accumulation of dust or other material that may enter the enclosure during use. 
         [0006]    According to another aspect of intervention, an after-treatment system is entirely housed in an externally mounted and vented after-treatment housing box next to the cab of a self-propelled sprayer and outside of the engine compartment. The after-treatment system has a diesel oxidation catalyst (DOC) unit, decomposition reactor (DRT) unit, and a selective catalytic reduction (SCR) unit all mounted in the after-treatment housing box. A first flexible bellows connects a pipe from the engine exhaust manifold to a downpipe that feeds the DOC at an inlet portion of the after-treatment system, vibration and movement isolating the after-treatment system from the engine. A second flexible bellows connects an outlet tube of the SCR to an exhaust stack at an outlet portion of the after-treatment system, vibration and movement isolating the after-treatment system from the exhaust stack. The after-treatment housing box has perforated front, back, top, bottom, inner side, and outer side walls. One end of the after-treatment housing box is isolation/rubber mounted to a single mounting point. The opposite end is rigid mounted through a multi-plane mounting arrangement with multiple fasteners. 
         [0007]    The externally mounted after-treatment housing box mounts the after-treatment system in a location that allows for easy component inspection, does not occupy space within a crowded engine compartment, and facilitates dissipating system heat while of minimizing heating of other components of the self-propelled sprayer. The DOC, DRT, and SCR are arranged in a stacked configuration with the SCR above the DOC and DRT to define a vertically climbing and longitudinally reversing exhaust flow path through the after-treatment system. This is done by receiving exhaust gases into the DOC at a forward end of the after-treatment housing box, such as through the perforated front wall. The exhaust flow is directed through the DOC and DRT in a first longitudinal direction. Exhaust flow leaves the DRT and is directed vertically up into the SCR at a rearward end of the after-treatment housing box. In the SCR, the exhaust flow changes direction from vertical to a second, opposite, longitudinal direction. The exhaust flow exits the SCR and thus the after-treatment system at the forward end of the after-treatment housing box, such as through the perforated front wall and is directed vertically upward through the exhaust stack. The DOC, DRT. and SCR have electrical, coolant, and DEF fluid connections with respective wire and hose leads to them. These components have defined maximum temperature thresholds to maintain part integrity. The engine exhaust gas and additional heat from regeneration cycles create significant heat radiation. The under/over orientation of the DOC, DRT, and SCR captures some of the electrical and fluid connections in an area where they have heat sources on two sides of them. To protect the electrical and fluid handling components from heat damage, there is a system of slots and holes to allow airflow through the after-treatment housing box. A perforated bottom wall of the after-treatment housing box draws in ambient air from below the after-treatment housing box. This helps establish a chimney effect within the after-treatment housing box through an opportunely directed box airflow path that removes heat from the DOC, DRT, and SCR. 
         [0008]    According to another aspect of the invention, an exhaust after-treatment mounting arrangement is provided, which may be used with an off-road agricultural vehicle. The off-road agricultural vehicle has a chassis supporting a cab and an engine compartment that houses an engine with an engine exhaust manifold and an engine exhaust pipe extending from the engine exhaust manifold away from the engine and out of the engine compartment. An exhaust stack at the end of the exhaust system releases exhaust gasses from the engine. The exhaust after-treatment mounting arrangement includes an exhaust after-treatment system for treating the exhaust of the engine as treated exhaust gasses. Treated exhaust gases are directed from the exhaust after-treatment system to the exhaust stack. An after-treatment housing box is arranged outwardly of the cab and the engine compartment and includes interconnected walls enclosing the exhaust after-treatment system. The after-treatment housing box includes a venting system for receiving ambient air into the after-treatment housing box and establishing an airflow through the after treatment housing box for cooling the exhaust after-treatment system. A flexible mounting system with flexible bellows allows relative movement of the exhaust after-treatment system and the after-treatment housing box relative to the cab and the engine compartment. A first flexible bellows is arranged between the engine exhaust pipe and an inlet portion of the exhaust after-treatment system. The first flexible bellows is configured to allow relative movement between the engine exhaust pipe and the exhaust after-treatment system. A second flexible bellows is arranged between the outlet portion of the exhaust after-treatments system and the exhaust stack. The second flexible bellows is configured to allow relative movement between the exhaust after-treatment system and the exhaust stack. 
         [0009]    According to another aspect invention, the venting system of the after-treatment housing box includes at least one perforated wall defined by at least one of the interconnected walls of the after-treatment housing box. The venting system may provide an arrangement of slots and holes. 
         [0010]    According to another aspect invention, the exhaust after-treatment system comprises a connector system including at least one of an electrical connector, a coolant connector, and a diesel exhaust fluid (DEF) connector arranged inside the after-treatment housing box. The venting system may be configured to direct an airflow through the after-treatment housing box for cooling the connector system. The exhaust after-treatment system may include at least one of a diesel oxidation catalyst (DOC) unit, a decomposition reactor (DRT) unit, and a selective catalytic reduction (SCR) unit. The exhaust after-treatment system may include each of the DOC, the DRT, and the SCR units, with the DOC unit receiving exhaust gasses from the engine, the DRT unit receiving exhaust gasses from the DOC unit, and the SCR unit receiving exhaust gasses from the DRT unit. The DOC, DRT, and SCR units may be arranged in a stacked configuration with the SCR unit arranged above the DOC and DRT units. The after-treatment housing box may include a perforated front wall and the DOC unit may be arranged adjacent to the perforated front wall. 
         [0011]    Other aspects, objects, features, and advantages of the invention will become apparent to those skilled in the art from the following detailed description and accompanying drawings. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the present invention, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present invention without departing from the spirit thereof, and the invention includes all such modifications. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings in which like reference numerals represent like parts throughout. 
           [0013]      FIG. 1  is a pictorial view of an off-road agricultural vehicle with an exhaust after-treatment mounting arrangement according to the present invention; 
           [0014]      FIG. 2  is an exploded pictorial view of an exhaust after-treatment mounting arrangement; and 
           [0015]      FIG. 3  is an exploded pictorial view of an after-treatment housing box of exhaust after-treatment mounting arrangement according to the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0016]    Referring now to the drawings and specifically to  FIG. 1 , an exhaust after-treatment mounting arrangement  5  having exhaust after-treatment system  7 , is shown used with off-road agricultural vehicle  9 . Off-road agricultural vehicle  9  is represented as an applicator  15 , shown here as a rear-boom self-propelled agricultural sprayer vehicle or rear-boom self-propelled sprayer, such as those available from CNH Industrial, such as the Miller Condor Series sprayers and New Holland Guardian Series rear-boom sprayers. Although applicator  15  is shown as a rear-boom self-propelled sprayer, it is understood that applicator  15  can instead be configured as a dry product spreader with a dry box or spinner box for broadcast-type delivery of dry product. Furthermore, applicator  15  can instead be a front-boom sprayer, such as those available from CNH Industrial, including the Miller Nitro and New Holland Guardian Series front-boom sprayers. It is further understood that off-road agricultural vehicle  9  may include other self-propelled implements, tractors, or other off-road agricultural vehicles  9 . 
         [0017]    Referring again to  FIG. 1 , applicator  15  includes chassis  20  having chassis frame  25  that supports various assemblies, systems, and components. These various assemblies, systems, and components include boom system  17 , cab  30 , and engine  35  housed in engine compartment  37 . In mechanical drive applications, a mechanical transmission receives power from engine  35  and delivers power for rotating wheels  45  by way of power-transmitting driveline components such as drive shafts, differentials, and other gear sets in portal, drop boxes, or other housings. For hydraulic drive systems, a hydraulic system receives power from engine  35  and includes at least one hydraulic pump which may be in a hydrostat arrangement for providing hydraulic pressure for operating hydraulic components within the hydraulic system, including hydraulic motors that are operably connected to the hydraulic pump(s) for rotating wheels  45 . Applicator  15  has a spray system  47  that includes storage containers such as a rinse tank storing water or a rinsing solution and product tank  55  that stores a volume of product  60  for delivery onto an agricultural field with applicator  15 . Product  60  includes any of a variety of agricultural liquid products, such as various pesticides, herbicides, fungicides, liquid fertilizers, and other liquids including liquid suspensions beneficial for application onto agricultural fields. A product delivery pump conveys product  60  from product tank  55  through plumbing components such as interconnected pieces of tubing and through a foldable and height adjustable boom of the boom system  17  for release out of spray nozzles that are spaced from each another along the width of boom during spraying operations of applicator  15 . 
         [0018]    Still referring to  FIG. 1 , exhaust after-treatment system  7  includes connector system  70  that has connectors  75  which may include various electrical connectors, coolant connectors, diesel exhaust fluid (DEF) connectors and injectors, probes and other sensors and operably connected to various components of exhaust after-treatment system  7  for their respective monitoring and control. Referring now to  FIG. 2 , components of exhaust after-treatment system  7  are shown as diesel oxidation catalyst (DOC) unit  90 , decomposition reactor (DRT) unit  95 , and selective catalytic reduction (SCR) unit  100 . When treating the exhaust gases in exhaust after-treatment system  7 , DOC unit  90  receives exhaust gasses from engine  35 . DRT unit  95  receives exhaust gasses from DOC unit  95  and SCR unit  100  receives exhaust gasses from DRT unit  95 . The DOC, DRT, and SCR  90 ,  95 ,  100  units are connected to each other with various fittings, pieces of tubing and/or connectors such as elbow  110  and clamp(s)  115 . DOC, DRT, and SCR  90 ,  95 ,  100  units are arranged in a stacked configuration with the SCR unit  100  arranged above the DOC and DRT units  90 ,  95 . 
         [0019]    Still referring to  FIG. 2 , exhaust after-treatment mounting arrangement  5  is configured to maintain temperatures of connector system  70  to not exceed maximum temperature thresholds to maintain part integrity of the connectors  75  or corresponding components, as explained in greater detail elsewhere herein. Exhaust after-treatment mounting arrangement  5  also flexibly supports the exhaust after-treatment system  7 , vibration and movement isolating the exhaust after-treatment system  7  from upstream and downstream components. First and second flexible bellows  120 ,  125  are respectively arranged upstream and downstream of the exhaust after-treatment system  7 , providing flexible connections between the exhaust after-treatment system  7  and corresponding components of the exhaust system. 
         [0020]    Still referring to  FIG. 2 , upstream of the exhaust after-treatment system  7 , pipe  130  extends from an exhaust manifold of engine  35 . Flexible bellows  120  extends between and interconnects pipe  130  to downpipe  135  connected to an inlet portion  140  of the exhaust after-treatment system  7 , shown here as the inlet of DOC unit  90 . In this arrangement, flexible bellows  120  allow for relative movement of the exhaust after-treatment system  7  with respect to engine  35 , providing vibration and movement isolation of the exhaust after-treatment system  7  relative to upstream components. 
         [0021]    Still referring to  FIG. 2 , downstream of the exhaust after-treatment system  7 , exhaust stack  150  extends in a generally vertical direction next to cab  30  ( FIG. 1 ), supported by cab  30  and/or chassis frame  25 . Flexible bellows  125  extends between and interconnects exhaust stack  150  to pipe segment  155  that is connected to an outlet portion  160  of the exhaust after-treatment system  7 , shown here as the outlet of SCR unit  100 . In this arrangement, flexible bellows  125  allow for relative movement of the exhaust after-treatment system  7  with respect to exhaust stack  150 , providing vibration and movement isolation of the exhaust after-treatment system  7  relative to downstream components. 
         [0022]    Referring again to  FIG. 1 , exhaust after-treatment mounting arrangement  5  includes after-treatment housing box  180  that is arranged outwardly of the cab  30  and the engine compartment  37  and includes interconnected walls enclosing the exhaust after-treatment system  7 . Referring again to  FIG. 2 , DOC, DRT, and SCR  90 ,  95 ,  100  units are secured in an interior space  185  of after-treatment housing box  180  by way of mounts  190 , shown here as clamp or strap mounts. 
         [0023]    Referring now to  FIG. 3 , ends, shown here as front and back ends  190 ,  195  of the after-treatment housing box  180 , are supported by the chassis frame  25 . One end, shown here as front end  190 , is rigid mounted to bracket  200  connected to chassis frame  25  and having multiple walls  205  into which a corner of the front end  190  nests, providing multi-plane rigid support. The other end, shown here as back end  195 , is isolation mounted to a single mounting point supported by bracket  215  that is connected to chassis frame  25 . The single mounting point may be defined by an isolation bushing  225  made from rubber or another resilient material arranged between bracket  215  and mounting tab  230  that extend generally horizontally away from back end  195 . After-treatment housing box  180  includes a main box  250 , shield  255 , and cap  260  that together define interconnected walls of an enclosure surrounding the exhaust after-treatment system  7 . Main box  250  has first and second compartments  265 ,  270  that together define the inside space  190  on opposite sides of a divider wall  275 . 
         [0024]    Still referring to  FIG. 3 , venting system  280  of the after-treatment housing box includes perforated surfaces of walls of the after-treatment housing box  180  that are configured to protect the electrical and fluid handling components from heat damage, by way of a system of slots and holes to allow airflow to permeate through the after-treatment housing box  180 . Bottom wall  285  of main box  250  has a relatively large elongate opening as slots  290  of venting system  280 , such that the bottom wall  285  defines a perforated wall with slots  290  as horizontally arranged slots. Slots  290  also extend through a lower portion of a back wall  295  of the main box  250  as vertically arranged slots. Shield  255  connects to the main box  250  by way of fasteners  300  extending through holes of a box rear flange  305  and a shield rear flange  310 . When the shield  255  is connected to the main box  250 , a rear wall segment  315  of the shield  255  defines an upper portion of the rear wall  295 . Rear wall segment  315  includes circular openings as holes  320  of venting system  280 , such that the rear wall  295  defines a perforated wall with slots  290  toward the bottom and holes  320  toward the top. Shield  255  includes outer wall  330  and a curved upper wall  335  extending from an upper portion of outer wall  330 . Outer and upper walls  330 ,  335  include circular openings as holes  340  of venting system  280 . which are shown as having smaller diameters than those of holes  320 . In this way, outer and upper walls  330 ,  335  define perforated walls with holes  340  covering outer and upper boundaries of the second compartment  270 . Cap  260  defines a curved upper wall  350  with circular openings as holes  340  of venting system  280  which, like those of outer and upper walls  330 ,  335 , have smaller diameters than those of holes  320 . Upper wall  350  of cap  260  defines a perforated wall covering an upper boundary of the first compartment  265 . A front wall  350  of the main box  250  has openings as holes  320  of venting system  280  extending through its upper portion, with holes  320  having larger diameters than those of holes  340 . Front wall  350  defines a perforated wall defining a forward boundary of the first compartment  265 . In this way, the after-treatment housing box  180  provides a perforated enclosure with openings of different sizes and at different locations as a system of slots and holes that can allow for a substantial amount of airflow upwardly and also longitudinally through the after-treatment housing box  180 , while freely allowing ambient air to permeate into and allow release of heated air from the after-treatment housing box  180 . 
         [0025]    Many changes and modifications could be made to the invention without departing from the spirit thereof. The scope of these changes will become apparent from the appended claims.