Abstract:
An exhaust treatment system for machine is disclosed that includes a burner body having an inlet for receiving a flow of exhaust, an outlet for the exhaust flow to exit, an opening and a receiving mount disposed around the opening. A fuel injector head is mounted over the opening in any one of a plurality of angular positions relative to the body. The burner body includes a plurality of mounting pads extending at least partially and circumferentially around the burner body for coupling a support bracket to the burner body in any one of a plurality of positions relative to the burner body. The support bracket may be used to couple the burner to a fixture device such as a cradle for supporting other exhaust treatment system components.

Description:
RELATED APPLICATION DATA 
     The present application is a continuation of U.S. patent application Ser. No. 12/644,595 filed Dec. 22, 2009, and entitled, “Radial Mounting for Regeneration Device,” which is hereby incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     This disclosure relates generally to heating systems for exhaust treatment devices such as particulate filters including, but not limited to diesel particulate filters (DPFs) and methods of retrofitting existing equipment with the disclosed heating systems. More specifically, this disclosure relates to flexible mounting schemes for coupling a burner and fuel injector head to a DPF, other type of filter or other type of emission control device that can be regenerated or activated with heat and that enables the disclosed burner and head to be mounted easily to many differently-configured exhaust treatment systems. 
     BACKGROUND 
     Engines, including diesel engines, gasoline engines, natural gas engines, and other known engines exhaust a complex mixture of air pollutants. The air pollutants may be composed of both gaseous and solid material, such as particulate matter. Particulate matter may include ash and unburned carbon particles called soot. 
     Due to increased environmental concerns, engine manufacturers have developed systems to treat engine exhaust after it leaves the engine. Some of these systems employ exhaust treatment devices such as particulate traps or filters to remove particulate matter from the exhaust flow. For diesel engines, the filter is often referred to as the DPF (diesel particulate filter). After an extended period of use, however, the filter material of the DPF may become partially saturated with particulate matter, thereby hindering the ability of the filter material to capture additional particulates and also hindering flow through the DPF. 
     However, the collected particulate matter in a DPF may be removed through a process called regeneration (i.e., regeneration of the filter). Specifically, a DPF may be regenerated by heating the filter material and the trapped particulate matter above the combustion temperature of the particulate matter, thereby combusting the accumulated particulate matter. The temperature of the exhaust flowing through a DPF may be raised using a flame producing burner specially configured for the particular equipment. One such system is disclosed in commonly assigned US2008/0078172. 
     SUMMARY OF THE DISCLOSURE 
     An exhaust treatment system is disclosed that includes a body including an inlet for receiving a flow of exhaust, an outlet for the exhaust flow to exit, an opening and a receiving mount disposed around the opening. The exhaust treatment system also includes an injector head including a head mount that engages the receiving mount of the body to mount the injector head over the opening of the body in one of a plurality of angular positions relative to the body. The body is coupled to or includes a plurality of mounting pads that extend at least partially and circumferentially around the body for coupling a support bracket to the body in one of a plurality of angular positions relative to the body. 
     A method of modifying an exhaust treatment system of a machine having an engine is also disclosed. The method includes orienting an injector head relative to a burner body in one of a plurality of positions and coupling the injector head to an opening in the burner body. The burner body includes an exhaust gas inlet and an exhaust gas outlet. The burner body also includes a plurality of pads extending at least partially around an outer surface the burner body. The method further includes securing a support bracket to one of the plurality of pads on the burner body in one of the plurality of angular positions with respect to the burner body. The method further includes coupling the exhaust gas inlet of the burner body to an exhaust conduit in communication with the engine and coupling the exhaust gas outlet of the burner body to an after-treatment device of the exhaust treatment system that can be regenerated by heat created in the burner body. The method also includes coupling the support bracket to the machine. 
     A machine is also disclosed that includes an engine connected to an exhaust treatment system. The exhaust treatment system includes a burner including a burner body including an inlet for receiving a flow of exhaust, an outlet connected to a particulate filter, an opening and a receiving mount disposed around the opening. The burner further includes an injector head including a head mount coupled to the receiving mount over the opening in one of a plurality of positions relative to the burner body. The burner body is coupled a plurality of mounting pads extending at least partially and circumferentially around the body for coupling a support bracket to the burner body in one of a plurality of angular positions relative to the body. The support bracket couples the burner body directly or indirectly to the machine. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagrammatic illustration of an exhaust treatment system, burner assembly and after-treatment device, which may be a DPF. 
         FIG. 2  is a bottom left perspective view of a disclosed burner and fuel injector head of a disclosed burner assembly with the fuel injector head removed. 
         FIG. 3  is a left perspective view of the disclosed burner assembly of  FIG. 2  with the fuel injector head connected to the burner. 
         FIG. 4  is right front perspective view of the disclosed burner assembly of  FIGS. 2-3 , coupled to a cradle and a DPF. 
         FIG. 5  is an enlarged view of the fuel injector head and exhaust inlet of the burner assembly illustrated in  FIG. 4 . 
         FIG. 6  is left front perspective view of the disclosed burner assembly of  FIGS. 2-5 , with the exhaust inlet rotated about 60° from the position illustrated in  FIGS. 4-5 . 
         FIG. 7  is an enlarged view of the fuel injector head and exhaust inlet of the burner assembly as illustrated in  FIG. 6 . 
         FIG. 8  illustrates the connection of a disclosed burner assembly to a cradle used for securing one or more additional components and the ability to rotate the burner and cradle about 180° while maintaining the position of the fuel injector head and related components. 
         FIG. 9  illustrates the connection of the disclosed burner assembly to a cradle which supports a DPF module and another after-treatment module. 
     
    
    
     DETAILED DESCRIPTION 
     Existing burner assemblies for exhaust systems are not configured for versatility; most burners are not useable with different engines and/or different exhaust systems of different sizes, shapes and configurations. Moreover, existing burner assemblies are often too large to be installed as part of an engine package. As a result, it may be difficult to accurately calibrate the burner and the engine system together as a working unit. 
     This disclosure is directed toward overcoming one or more of the flexibility and size constraints set forth above. While the examples of this disclosure are directed primarily to diesel engines and DPFs, one skilled in the art will appreciate that this disclosure is clearly applicable to other fossil fuel burning engines that employ filters that both trap particulates and that are robust enough for heat-based regeneration. Further, one skilled in the art will also appreciate that the disclosed burner assemblies are also applicable to other emission-control devices that can be activated with heat, such as certain catalyst systems. 
       FIG. 1  illustrates an exhaust treatment system  20  for an engine  24 . The engine  24  may be an internal combustion engine, such as a gasoline engine, a diesel engine, a natural gas engine or any other exhaust gas producing engine. The engine  24  may provide power to a moving vehicle or be part of a stationary power generator, pump system, etc. The exhaust treatment system  20  may include a plurality of after-treatment devices  28  that may be periodically regenerated or activated with heat from the one or more burner assemblies  35 . 
     The one or more burner assemblies  35  may be disposed upstream of one or more after-treatment devices  28 . In one embodiment, the after-treatment device  28  may include a particulate filter  29 , such as a DPF. The particulate filter  29  may be configured to remove one or more types of particulate matter from the exhaust gases produced by engine  24  and flowing through an exhaust conduit  30  from the engine  24  to the after-treatment device(s)  28 . The particulate filter  29  may include an outer housing  32 , which may encase a filter material  34  for trapping particulate matter. The filter material  34  should to be robust enough to withstand a heat-based regeneration. 
     Although the after-treatment device  28  is discussed herein includes a particulate trap or filter  29  such as a DPF, in other embodiments, after-treatment device  28  may include a selective catalytic reduction device (SCR), catalytic converter, catalytic particulate trap, NOx adsorber, or any other after-treatment device that may be activated with heat or that may operate under conditions hot enough for the periodic regeneration of the filter  29 . Alternatively or additionally, the after-treatment devices  28  may include combinations of these devices. For example, after-treatment device  28  may include a particulate filter  29  and an SCR in series, which, in some embodiments, may be integrated into the same unit (e.g., in the same housing  32 ). 
     To regenerate the filter  29  with heat, the exhaust treatment system  20  may include a burner assembly  35  configured heat the exhaust stream upstream from the filter  29 . For example, the burner assembly  35  may include a burner  36  configured to increase the temperature of the exhaust gases flowing through exhaust conduit  30  upstream from the filter  29  and the after-treatment device(s)  28 . Accumulation of solid exhaust flow constituents the filter  29  and/or other components of the after-treatment device  28  may result in a decline in engine performance and/or possible damage to after-treatment device  28  and/or other components of exhaust treatment system  20 . The burner  36  may be configured to cause at least some of the particulate matter that may have accumulated in the filter  29  and other components of the after-treatment device  28  to be combusted or burned off. 
     Although the exhaust treatment system  20  is shown with a single after-treatment device  28 , a single filter  29  and a single burner assembly  35 , the exhaust treatment system  20  may include more than one after-treatment device  28 , more than one filter  29  and/or more than one burner assembly  35 . For example, in one embodiment, the exhaust treatment system  20  may include a single burner assembly  35  configured to regenerate or activate a plurality of after-treatment devices  28 . In another embodiment, the exhaust treatment system  20  may include two burner assemblies  35  configured to regenerate or activate from one or more after-treatment devices  28 . 
     For purposes of the following explanation, the after-treatment device  28  of the exhaust treatment system  20  will be discussed as including a filter, particulate trap or DPF  29 , while the burner assembly  35  will be discussed as including a burner  36  and fuel injector head  40 . The exhaust treatment system  20  may also include a controller  38  configured to receive information from various sources and to control one or more components of exhaust treatment system  20  based on the sensed information. 
     The burner assembly  36  may be positioned anywhere along the exhaust conduit  30  between the engine  24  and the DPF  29 . The burner assembly  35  may include a fuel injector with a head  40 , spark plug  50 , igniter coil  52 , flame sensor or thermocouple  64 , all of which is shown schematically in  FIG. 1 . Although the burner  36 /fuel injector head  40  has been shown and described as including the spark plug  50 , alternative ignition sources may be employed, such as, for example, glow plugs or any other means for igniting an air/fuel mixture. 
     To the supply the fuel injector head  40  with fresh air for mixing with the fuel for combustion, as well as for flushing fuel injector head  40  of any fuel or debris before and/or after operation of burner  36 , an air intake system  42  associated with the engine  24  is provided. Air may be routed from a portion of air intake system  42 , such as an intake manifold  44 , downstream from a compressor  46  configured to create forced induction for the engine  24 . The compressor  46  may include a turbocharger, supercharger, or any other device configured to compress intake air and thereby produce forced induction for engine  24 . Additional air may be directed from intake manifold  44  to the fuel injector head  40  via an air conduit  48 . The supply of air to the burner fuel injector head  40  may be regulated by an air valve  49 , which is controllable by controller  38 . 
     The controller  38  may be configured to activate the burner assembly  35  in response to a trigger condition. That is, the controller  38  may monitor for various trigger conditions, and if any of them are met, then the controller  38  may activate the burner assembly  35 . The trigger conditions may include, for example, operation of engine  24  for a predetermined amount of time; consumption of a predetermined amount of fuel by the engine  24 ; detection of an elevated backpressure upstream of the DPF  29  above a predetermined pressure; detection of a pressure differential across the DPF  29  of greater than a predetermined amount; and determination that a calculated amount of particulate matter has accumulated in the DPF  29  is above a predetermined amount. 
     Regeneration of the DPF  29  may also be initiated manually by an operator, owner, service technician, etc. The exhaust treatment system  20  may include various sensors configured to generate information about operating parameters of the exhaust treatment system  20 . For example, the exhaust treatment system  20  may include an upstream temperature sensor  54 , an upstream pressure sensor  56 , a downstream temperature sensor  58 , and a downstream pressure sensor  60 . Such sensors may be positioned along exhaust conduit  30  upstream and downstream from the DPF  29  respectively and configured to take measurements of the temperature and pressure of the exhaust gases within exhaust conduit  30  at their respective locations. Such measurements may be received by the controller  38 . In addition to fuel on/off valve  70 , the exhaust treatment system  20  may also include a fuel pressure regulator valve  72  controllable by controller  38  to regulate the pressure of the fuel, and thereby the rate at which fuel is delivered to the fuel injector head  40 . 
     The exhaust treatment system  20  may also be configured to monitor the stability of the regeneration process by determining a difference between the upstream exhaust temperature measured by upstream temperature sensor  54  and the downstream exhaust temperature measured by the downstream temperature sensor  58 . If the temperature measured by the downstream temperature sensor  58  exceeds that measured by the upstream temperature sensor  54  by more than a predetermined amount for more than a predetermined amount of time, the controller  38  may initiate steps to scale back or terminate the regeneration process. For example, in such a case, the controller  38  may reduce the intensity of the flame produced by burner  36 . In some circumstances, the controller  38  may terminate the regeneration process if the regeneration process is significantly unstable (e.g., if the downstream exhaust temperature exceeds a predetermined value or it exceeds the upstream exhaust temperature by more than a predetermined amount). 
     Turning to  FIGS. 2-3 , the burner  36  includes an burner body  81  with an exhaust gas inlet  82  and an exhaust gas outlet  83 . The burner body  81  is also connected to the fuel injector head  40  by a plurality of fasteners  84  distributed circumferentially about the fuel injector head  40  and that pass through a head mount  79  ( FIG. 2 ). Corresponding threaded openings  76  are disposed in the receiving mount  85  of the burner body  81  which enables the head mount  79  of the fuel injector head  40  to be mounted on the receiving mount  85  of the burner body  81  of the burner  36  in a variety of different angular positions. 
     In addition to the annular receiving mount  85  that couples the burner body  81  to the fuel injector head  40 , the burner body  81  may include an additional circumferential mounts or pads  97  on its outer surface  80  for coupling the burner body  81  to the bracket  88  at select angular positions. The circumferentially spaced pads  97  each may include one or more threaded openings  87  for coupling the proximal end  91  of the bracket  88  to one of the pads  97  on the burner body  81  in one of a variety of circumferential positions along the partial ring of pads  97  and therefore different angular positions with respect to a central axis  94  of the burner  36 . The pads  97  and threaded openings  87  may form part of the burner body  81  or the partial ring of pads  97  and threaded openings  87  may be coupled to the burner body  81  by welding or other forms of attachment. 
     The bracket  88 , by way of its fasteners  89  can be mounted to the one of the pads  97  and to the burner body  81  of the burner  36  at varying angular positions as shown in  FIGS. 4-8 . In the embodiment shown in  FIGS. 2-8 , seven pads  97  are provided which enable rotation of the burner body  81  up to about 180° with respect to the bracket  88  as illustrated by the arc  98  in  FIG. 8 . As a result, the burner assembly  35  and cradle  90  combination of  FIG. 8  may be retrofitted for use with exhaust systems of many different manufacturers and of various types of equipment. 
     Referring to  FIGS. 4-7 , the burner  36  can be rotated for purposes of coupling the exhaust inlet  82  to an exhaust line. To maintain the angular position of the fuel injector head  40  and related injector components  95  while the burner  36  is rotated, the fasteners  84  ( FIGS. 2-3 ) are loosened, the bracket  88  is disconnected and the position of the fuel injector head  40  may be held by hand or other clamp device as the burner  36  and burner body  81  are rotated from the position shown in  FIGS. 4-5  to the position shown in  FIGS. 6-7  before re-coupling the bracket  88  to the burner body  81  at the desired orientation and/or re-coupling the bracket  88  to the cradle  90  or other supporting device with the fasteners  89 ,  96  ( FIG. 3 ). As the fuel injector head  40  is connected to additional components shown collectively at  95  in  FIGS. 4 and 6  that may include fuel input lines, coolant input and output lines, a lead for the thermocouple or flame sensor, spark plug to igniter lead, air inlet line, etc., avoiding any rotation of the fuel injector head  40  may helpful. 
       FIG. 9  illustrates the connection of the disclosed burner  36  and fuel injector head  40  to a DPF  29  and another after-treatment module  99 . A catalyst module or SCR module, although not shown, may be supported as well. 
     INDUSTRIAL APPLICABILITY 
     As noted above existing burner assemblies for exhaust systems are not configured for versatility; most burners are not useable with different engines and/or different exhaust systems of different sizes, shapes and configurations. As shown in  FIG. 8 , with the seven pads  97  spaced along an arc of about 180° around the burner body  81 , the exhaust inlet  82  may be placed at many different angular positions, only three of which are shown in  FIGS. 5 ,  7  and  8 . However, as shown in  FIGS. 2-3 , the fuel injector head  40  may be easily removed from the burner body  81 , and holding the head  40  and associated components  95  in place, the burner body  81  may be rotated to place the inlet  82  in the correct or desired position. Further, the cradle  90  and bracket  88  may be adjusted independently from the burner body  81  and exhaust inlet  82 . As a result, the disclosed burner/fuel injector assembly  35  overcomes one or more of the flexibility, versatility and size constraints of existing designs. While the examples of this disclosure are directed primarily to diesel engines and DPFs, one skilled in the art will appreciate that this disclosure is clearly applicable to other fossil fuel burning engines that employ filters that both trap particulates and that are robust enough for heat-based regeneration. Further, one skilled in the art will also appreciate that the disclosed burner assemblies are also applicable to other emission-control devices that can be activated with heat, such as certain catalyst systems. 
     As illustrated in  FIG. 2 , the threaded openings  76  disposed in the receiving mount  85  of the burner body  81  enable the fuel injector head  40  to be mounted to the burner body  81  of the burner  36  and a variety of different angular positions. Further, the burner body  81  includes an additional circumferential mounts in form of the spaced-apart pads  97 . The pads  97  include one or more threaded openings  87  for mounting the proximal end  91  of the bracket  88  to the burner body  81  at a variety of different angular positions with respect to an axis  94  of the burner  36 . In other words, the bracket  88 , by way of its fasteners  89  can be mounted to the burner body  81  of the burner  36  at varying angular positions as shown in  FIG. 8  and the fuel injector head may be mounted to the burner body  81  in a variety of angular positions as shown in  FIG. 2 . This flexibility allows the exhaust gas inlet  82  to be moved generally along the arc  98  shown in  FIG. 8 . As a result, the burner  36  and cradle  90  combination may be retrofitted onto exhaust systems of various manufacturers and various types of equipment.