Patent Publication Number: US-2011061625-A1

Title: Exhaust throttle-egr valve module for a diesel engine

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of non-provisional application Ser. No. 11/527,089 filed Sep. 26, 2006 which was a continuation-in-part of non-provisional application Ser. No. 11/475,629, filed Jun. 27, 2006, which was a continuation-in-part of PCT Application No. PCT/US06/04345, filed Feb. 7, 2006, and a continuation-in-part of PCT Application No. PCT/US06/04345, filed Feb. 7, 2006, which both claim the benefit of U.S. Provisional Application No. 60/696,854, filed Jul. 6, 2005 and Provisional Application No. 60/650,752, filed Feb. 7, 2005. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an exhaust gas module that directs gaseous fluid to a plurality of openings. 
     BACKGROUND OF THE INVENTION 
     Due to both federal and state regulations, motorized vehicles today are limited to the amount of emissions in which they can release during operation. One way of reducing the amount of emissions released by the vehicle is to include an air management assembly having an exhaust gas recirculation (EGR) valve. The EGR valve directs at least a portion of the gaseous fluid from an exhaust manifold of the engine, so that the gaseous fluid is recirculated into an intake manifold of the engine along with fresh air. The EGR valve is controlled by an actuator in order to control the amount of gaseous fluid passing through the EGR valve and being recirculated into the intake manifold. 
     Further, an exhaust gas throttle valve is typically placed in the air management assembly which further controls the amount of gaseous fluid that passes through an EGR path to be recirculated in to the intake manifold or through an exhaust pipe to exit the air management assembly. Thus, the EGR valve and the exhaust gas throttle both control the amount of gaseous fluid recirculating through the intake side of the air management assembly, but are separate components and are separately controlled. 
     Therefore, it would be desirable to develop a module which provides a housing having a plurality of openings with a valve that controls the amount of gaseous fluid passing through the openings so that a valve controlled by a single actuator can replace the separate EGR valve and the exhaust gas throttle valve, and control the amount of gaseous fluid flowing through the EGR path and to the exhaust pipe. 
     SUMMARY OF THE INVENTION 
     An embodiment of the present invention relates to a valve assembly for use in an air management assembly having an engine, an exhaust side, and an intake side, where the valve assembly provides a housing, a plurality of openings in the housing, a valve in the housing, and an actuator operably connected to the valve. The housing is in fluid communication with the exhaust side and the intake side. The plurality of openings in the housing form at least one inlet and at least one outlet in the housing. The valve moves with respect to the plurality of openings. 
     Another embodiment of the present invention relates to a valve assembly for use in an air management assembly having an engine, an exhaust side, and an intake side, where the valve assembly provides a housing, an exhaust gas recirculation (EGR) cooler, an air intake, a compressor, a plurality of openings, a valve in the housing, and an actuator operably connected to the valve. The housing is in fluid communication with the exhaust side and the intake side. The EGR cooler is in fluid communication with the exhaust side. The air intake forms at least a portion of the intake side. The compressor is in fluid communication between the engine and the air intake. The plurality of openings form at least one inlet and at least one outlet. A first inlet is in fluid communication with the EGR cooler. A second inlet is in fluid communication with the air intake. An outlet is in fluid communication with the compressor. The valve in the housing moves with respect to the plurality of openings. 
     Another embodiment of the present invention relates to a valve assembly for use in an air management assembly having an engine, an exhaust side, and an intake side, where the valve assembly provides a housing, an EGR cooler, a charge air cooler, a plurality of openings in the housing, a valve in the housing, and an actuator operably connected to the valve. The housing is in fluid communication with the exhaust side and the intake side. The EGR cooler is in fluid communication with the exhaust side. The charge air cooler forms at least a portion of the intake side. The plurality of openings in the housing form at least one inlet and at least one outlet. A first inlet is in fluid communication with the EGR cooler. A second inlet is in fluid communication with the charge air cooler. The outlet is in fluid communication with the engine. The valve in the housing moves with respect to the plurality of openings. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a perspective view of an exhaust throttle-exhaust gas recirculation module in accordance with a preferred embodiment of the present invention; 
         FIG. 2  is a cross-sectional perspective view of a valve and a plurality of openings of a housing in accordance with a preferred embodiment of the invention; 
         FIG. 3  is a side cross-sectional schematic view of the valve and plurality of openings of a housing in accordance with an alternate embodiment of the invention; 
         FIG. 4  is a schematic diagram of an air management assembly in accordance with an embodiment of the present invention, and alternate embodiments are shown in phantom where an exhaust throttle-exhaust gas recirculation module can alternatively be located in the air management assembly; 
         FIG. 5  is a cross-sectional schematic view of an exhaust throttle-exhaust gas recirculation module having an opening in a housing with a substantially similar diameter as a filter that is in fluid communication with the module in accordance with an embodiment of the invention; 
         FIG. 6  is a cross-sectional schematic diagram of an exhaust throttle-exhaust gas recirculation module with an alternate feature shown in phantom in accordance with the present invention; 
         FIG. 7  is a perspective view of a valve used in an exhaust throttle-exhaust gas recirculation model in accordance with an embodiment of the present invention; and 
         FIG. 8  is a block diagram of a method for controlling the flow of gaseous fluid through a plurality of openings using a single actuated valve. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Referring to  FIGS. 1-3 ,  5 , and  6 , a valve assembly or an exhaust throttle-exhaust gas recirculation valve module (ETVM) is generally shown at  10 . The ETVM  10  has a housing  12  with a plurality of openings. The openings form at least one inlet  14  and at least one outlet  16 . In a preferred embodiment, the housing  12  has one inlet  14  and two outlets  16 . A first outlet  16   a  is an exhaust gas recirculation (EGR) path and a second outlet  16   b  is an exhaust path. The housing  12  also contains valve  18  which is used to direct the flow of gaseous fluid or exhaust gas inside the housing  12  by being placed in different positions with respect to the EGR path  16   a  and the exhaust path  16   b.    
     A single actuator  20  is used to control the valve  18 . In a preferred embodiment, the actuator  20  is operably connected to an electric motor  22  so that the actuator  20  alters the position of the valve  18  in the desired position with respect to the EGR path  16   a  and the exhaust path  16   b . The use of a single actuator  20  to control a single valve  18  that directs the flow of gaseous fluid through both the EGR path  16   a  and exhaust path  16   b  is beneficial because of the reduction in the number of parts needed to operate the ETVM  10  when compared to an assembly using a separate EGR valve (not shown) and exhaust gas throttle valve (not shown). For example, if the EGR path  16   a  and exhaust path  16   b  had separate actuators, there would be an additional actuator and an additional power source to operate the additional actuator when compared to the ETVM  10 . Thus, by using a single actuator  20 , the manufacturing process is more efficient because less parts need to be produced and assembled. 
     In a preferred embodiment, the flow of gaseous fluid through the ETVM  10  is primarily controlled by the valve  18  being placed with respect to the EGR path  16   a . Thus, as gaseous fluid flows into the housing  12  through the inlet  14 , the valve  18  as controlled by the actuator  20 , directs the gaseous fluid through either, both, or neither of the EGR path  16   a  and the exhaust path  16   b . When the valve  18  is positioned so that the EGR path  16   a  is completely open, an amount of gaseous fluid passes through the EGR path  16   a  due to the pressure in the housing  12  and inlet  14  created by the gaseous fluid. However, to further increase the flow through the EGR path  16   a , the actuator  20  positions the valve  18  to completely close the exhaust path  16   b , which increases the back pressure of the gaseous fluid in the housing  12  and inlet  14 . This increase in back pressure causes a greater amount of gaseous fluid to flow through the EGR path  16   a . Further, the valve  18  can be placed in any position where the EGR path  16   a  and exhaust path  16   b  are fully open, closed, partially open, or any combination thereof, in order to obtain the desired amount of gaseous fluid flowing through the EGR path  16   a  and the exhaust path  16   b.    
     In a preferred embodiment, the valve  18  is a disc that is angled with respect to the EGR path  16   a  and the exhaust path  16   b . Thus, the valve  18  is operably connected to the actuator  20  and the valve rotates about the longitudinal axis of the housing  12  in order to close and open the EGR path  16   a  and the exhaust path  16   b  as desired. In reference to  FIG. 7 , a preferred embodiment of the valve  18  has a first orifice  21   a  and a second orifice  21   b . The orifices  21   a ,  21   b  are shaped so that the valve  18 , in conjunction with a fixed plate  25  in the housing  12 , can fully open the inlets  14  and outlets  16 , close the inlets  14  and outlets  16 , partially open the inlets  14  and outlets  16 , or any combination thereof. The first orifice  21   a  is larger than the second orifice  21   b  so that both the EGR path  16   a  and exhaust path  16   b  can be at least partially opened. The second orifice  21   b  is designed so that one of the EGR path  16   a  is at least partially open, and the exhaust path  16   b  is closed or vice versa. Further, the shape of the orifices  21   a ,  21   b  allow for an efficient flow of the gaseous fluid by reducing the amount of resistance caused by the valve  18  when compared to other valve  18  designs. 
     In an alternate embodiment, the valve  18  has a semi-circle disc shape so that the valve  18  is capable of being placed as to close the EGR path  16   a  and the exhaust path  16   b , fully open the EGR path  16   a  and the exhaust path  16   b , partially open the EGR path  16   a  and exhaust path  16   b , or any combination thereof. Furthermore, the valve  18  has an aerodynamic angle in order to efficiently direct the flow of gaseous fluid to the desired location. Thus, the angle of the valve  18  is designed to reduce the amount of resistance applied to the gaseous fluid from the valve  18 . It should be appreciated that any predetermined valve  18  design is capable of being placed with respect to the openings of the housing  12  in order to allow the gaseous fluid to flow through the housing  12  as described above. 
     Referring to  FIG. 3 , in an alternate embodiment, the valve  18  rotates about a cross-sectional axis in order to close the EGR path  16   a  and exhaust path  16   b  as desired. Similar to the disc embodiment described above, the valve  18  can be a flapper, with a plurality of planes  23  extending from a point or the cross-sectional axis, so that the valve  18  is capable of being placed to close the EGR path  16   a  and exhaust path  16   b , fully open the EGR path  16   a  and exhaust path  16   b , partially open the EGR path  16   a  and exhaust path  16   b , or any combination thereof. In addition, the valve  18  is designed with an aerodynamic angle in order to reduce the amount of resistance applied to the gaseous fluid by the valve  18 . 
     In an alternate embodiment, the planes  23  extending from the point or cross-sectioned axis can be angled so that they do not extend directly radially from the point. The angled shape of the planes  23  is for the aerodynamic angle as stated above and/or to create a more efficient flapper design to open and close the openings in the housing  12  in a predetermined manner. 
     Referring to  FIG. 4 , a preferred embodiment of an air management assembly including the ETVM  10  is generally shown at  24 . Alternate embodiments of the air management assembly  24  are shown in phantom. With reference to  FIGS. 1-7 , an engine  26  has an exhaust gas manifold  28  where the gaseous fluid exits the engine  26 . The gaseous fluid passes through the exhaust gas manifold  28  to a turbine  30 . The gaseous fluid rotates the turbine  30 . Thus, the turbine  30  is in fluid communication with the exhaust gas manifold  28 . In a preferred embodiment, the gaseous fluid then passes through a diesel particulate filter (DPF)  32  and into the ETVM  10 , so that the turbine  30 , DPF  32 , and ETVM  10  are in fluid communication with one another. 
     In one embodiment, the inlet  14  of the housing  12  of the ETVM  10   a  is directly connected to the outlet end of the DPF  32  in order to reduce the space occupied by the air management assembly  24 . In addition, by having the direct connection between the ETVM  10   a  and the DPF  32  there is less leakage of gaseous fluid due to the reduction in connection points, which results in the prevention of a pressure drop of the gaseous fluid, and simplified assembly due to the reduction in parts. 
     With specific reference to  FIG. 5 , in a preferred embodiment when the ETVM  10   a  is directly connected to the DPF  32 , the opening of the housing  12  that is connected to the DPF  32  has substantially the same diameter as the DPF  32 . By having the inlet  14  that is substantially the same diameter as the DPF  32 , the gaseous fluid has substantially the same area to flow through from the DPF  32  to the ETVM  10   a  rather than having a reduction in the area in which the gaseous fluid can flow creating a bottleneck, which results in a reduction of the gaseous fluid flow rate. Therefore, this design for connecting the ETVM  10   a  and the DPF  32  allows for an efficient flow of gaseous fluid through the two components. 
     With continued reference to  FIGS. 1-7 , no matter where the DPF  32  is located with respect to the ETVM  10 , the gaseous fluid that enters the ETVM  10  through the inlet  14  is directed to pass through one, both, or neither of the EGR path  16   a  and exhaust path  16   b  as described above. The exhaust gas that passes through the exhaust path  16   b  then flows through an exhaust pipe  34  and is discharged from the engine assembly  24 . Thus, the gaseous fluid remains on the exhaust side generally indicated at  35 , until it exits the air management assembly  24 . The exhaust side  35  includes at least the exhaust gas manifold  28 , the turbine  30 , the DPF  32 , and the exhaust pipe  34 . 
     The gaseous fluid that is directed through the EGR path  16   a  then passes through an EGR path  36  in the air management assembly  24 , into a gaseous fluid cooler or EGR cooler  38  that is in fluid communication with the ETVM  10 . After the gaseous fluid has passed through the EGR cooler  38 , the gaseous fluid is combined with fresh air through an air intake  40 . The mixture of gaseous fluid and fresh air then enters a compressor  42  where the pressure of the gaseous fluid mixture is increased. Thus, the EGR cooler  38 , air intake  40 , and compressor  42  are in fluid communication with one another. Typically, the compressor  42  is moveably coupled to the turbine  30 , such that the gaseous fluid that rotates the turbine  30  causes the compressor  42  to rotate. 
     Once the gaseous fluid mixture has been compressed and exits the compressor  42 , the gaseous fluid mixture passes through a gaseous fluid cooler or a charge air cooler  44  that is in fluid communication with the compressor  42 . The charge air cooler  44  reduces the temperature of the gaseous fluid mixture. Then the gaseous fluid mixture flows into an intake manifold  46  of the engine  26  that is in fluid communication with the charge air cooler  44 . Thus, the gaseous fluid mixes with the fresh air on an intake side  48  of the air management assembly  24  which includes at least the air intake  40 , the compressor  42 , the charge air cooler  44 , and the intake manifold  46 . In an alternate embodiment, the ETVM  10  is placed anywhere in the air management assembly  24  where it is beneficial to have an EGR valve and a control mechanism for altering the flow of gaseous fluid controlled by a single actuator  20 . 
     In reference to  FIGS. 4 and 6 , in an alternate embodiment, the ETVM  10   b  can be placed on the intake side  48  of the air management assembly  24 . In this embodiment, a first inlet  14   a  in the housing  12  is in fluid communication with the exhaust side  35 ; thus, the inlet  14   a  relates to the EGR path  16   a  described above. In a preferred embodiment, the first inlet  14   a  is in fluid communication with the EGR cooler  38 . The EGR cooler  38  is in fluid communication with the exhaust side  35  after the gaseous fluid passes through the turbine  30 . A second inlet  14   b  in the housing  12  is in fluid communication with the air intake  40 ; thus, the second inlet  14   b  relates to the exhaust path  16   b  described above, except in this embodiment it is an intake path. The housing  12  also has a first outlet  16   a ′ that is in fluid communication with the engine  26 . In a preferred embodiment, the first outlet  16   a ′ is in fluid communication with the compressor  42 . Thus, the ETVM  10   b  forms at least a portion of the intake side  48 . The valve  18  operates in the same manner as described above, except that the valve  18  is positioned with respect to the inlets  14   a  and  14   b  rather than the outlet  16   a ′; thus, the valve  18  can be positioned so that the first inlet  14   a  and second inlet  14   b  can be fully open, closed, partially open, or any combination thereof. 
     In another alternate embodiment, the ETVM  10   c  forms at least a portion of the intake side  48 , so that the first inlet  14   a  is in fluid communication with a gaseous fluid cooler or an EGR cooler  50 . Similar to above, the first inlet  14   a  relates to the EGR path  16   a . However, ETVM  10   c  maintains the same design as ETVM  10   b  as described above and shown in  FIG. 6 . The EGR cooler  50  is in fluid communication with the exhaust side  35  prior to the gaseous fluid passing through the turbine  30 . The second inlet  14   b  is in fluid communication with the charge air cooler  44 . Similar to above, the second inlet  14   b  relates to the exhaust path  16   b . The first outlet  16   a ′ is in fluid communication with the engine  26 . As stated above, for the embodiment where the ETVM  10   c  is on the intake side  48 , the valve  18  functions in the same manner except the valve moves with respect to the inlets  14   a  and  14   b.    
     In reference to  FIG. 6 , in an alternate embodiment the ETVM  10  has a pressure sensor  52  that is connected to at least two of the openings in the housing  12 . This alternate embodiment is described with respect to ETVM  10  for example purposes only, and can be included on, but not limited to, any ETVM  10 ,  10   a ,  10   b ,  10   c  design. Preferably the openings the pressure sensor  52  is connected to are on opposite sides of the valve  18 . The pressure sensor  52  can then determine the pressure difference between the openings on opposite sides of the valve  18 . The pressure difference can then be used to determine how the actuator  20  should alter the position of the valve  18  in order to get the desired flow of gaseous fluid through the housing  12 . 
     As described above, the valve  18  can be positioned in order to fully open the EGR path  16   a  and partially or fully close the exhaust path  16   b  in order to raise the back pressure of the gaseous fluid in the housing  12 . Raising the pressure of the gaseous fluid in the housing  12  is beneficial when the engine  26  is being shut off or to raise the temperature of the gaseous fluid in the air management assembly  24 . As described above, the single actuator  20  is used to control the valve  18  in order to position the valve  18  with respect to the EGR path  16   a  and the exhaust path  16   b . Raising the back pressure of the gaseous fluid in this way is beneficial due to the increase in back pressure acting as an engine shut off. Thus, the increase in gaseous fluid back pressure increases the engine  26  load which causes the engine  26  to shut off. Further, the raise in temperature of the gaseous fluid is beneficial because the increased temperature acts as a catalyst to begin oxidation of the gaseous fluid during low driving cycles. 
     Referring to  FIGS. 1-8 , a method for controlling the amount of exhaust gas recirculation in a preferred embodiment of the air management assembly  24  provides a first step where the actuator  20  receives a signal from a control system at decision box  54 . In a preferred embodiment, the control system is an engine control unit (ECU) (not shown), and the ECU is programmed to determine the desired valve  18  location and/or the gaseous fluid flow through the ETVM  10 ,  10   a ,  10   b ,  10   c . In an alternate embodiment, the control unit is the actuator  20 , which acts similar to the ECU described above in that the actuator  20  determines the desired location of the valve  18  and/or the gaseous fluid flow through the ETVM  10 ,  10   a ,  10   b ,  10   c  and adjusts the valve  18  accordingly. In either of the two embodiments described above, the ECU or the actuator  20  typically receives signals from a position sensor (not shown), a pressure sensor  52 , a mass air flow sensor, or the like, to determine the current location of the valve  18 . It should be appreciated that any type of sensor can be used, so long as the adjustment to the ETVM  10 ,  10   a ,  10   b ,  10   c  is determined in order to obtain the desired output from the ETVM  10 ,  10   a ,  10   b ,  10   c.    
     After the actuator  20  has received a control signal, the actuator  20  alters the position of the valve  18  accordingly at decision box  56 . Thus, depending on the amount of gaseous fluid that is to be directly released from the air management assembly  24 , the actuator  20  positions the valve  18  to direct gaseous fluid through the EGR path  16   a ,  14   a  opening and the exhaust path  16   b  or relating second opening  14   b . Next, at decision box  58 , it must be determined if the valve  18  is positioned such that the EGR path  16   a ,  14   a  opening is substantially open. If it is determined that the EGR path  16   a ,  14   a  opening is substantially open, then at decision box  60  the actuator  20  controls the valve  18  in order to further increase the amount of gaseous fluid flowing through the EGR path  16   a ,  14   a  opening by closing the exhaust path  16   b  or relating second opening  14   b . However, if it is determined that the EGR path  16   a ,  14   a  opening is not substantially open, then at decision box  62  the actuator  20  continues to control the valve  18  in order to control the amount of gaseous fluid flowing through the EGR path  16   a ,  14   a  opening and exhaust path  16   b  or relating second opening  14   b . After both decision box  60  and  62 , the method for controlling the amount of exhaust gas recirculation returns to decision box  54  so that the actuator  20  receives a signal in order to further control valve  18 . 
     In a preferred embodiment, it is determined if the EGR path  16   a ,  14   a  opening is substantially open prior to altering the valve  18  with respect to the exhaust path  16   b  or relating second opening  14   b  because it is undesirable to increase the back pressure of the gaseous fluid to increase the flow of gaseous fluid through the EGR path  16   a ,  14   a  opening if the EGR path  16   a ,  14   a  opening is not substantially open. Thus, if the EGR path  16   a ,  14   a  opening is not substantially open, the valve  18  is placed to open the EGR path  16   a ,  14   a  opening to increase the flow of gaseous fluid through the EGR path  16   a ,  14   a  opening rather than increasing the back pressure. In a preferred embodiment, the valve  18  is placed so that the EGR path  16   a ,  14   a  opening is completely open prior to the valve  18  being placed with respect to the exhaust path  16   b  or relating second opening  14   b  to alter the flow of gaseous fluid through the EGR path  16   a ,  14   a  opening. However, it is within the scope of the invention to control the flow of gaseous fluid through the exhaust path  16   b  or relating second opening  14   b  prior to the valve  18  completely opening the EGR path  16   a ,  14   a.    
     In an alternate embodiment for controlling the valve  18  in any of the embodiments of the air management assembly, the actuator  20  moves the valve  18  with respect to the openings in the housing  12 , such that the opening related to the exhaust path  16   b  or relating second opening  14   b  is fully open until the opening relating to the EGR path  16   a ,  14   a  is fully open. Once the opening relating to the EGR path  16   a ,  14   a  is fully open, the valve  18  immediately begins to be repositioned by the actuator  22  to at least partially close the opening relating to the exhaust path  16   b  or relating second opening  14   b.    
     In another alternate embodiment, the valve  18  moves with respect to the openings in the housing  12 , so that the opening relating to the exhaust path  16   b  or relating second opening  14   b  and the opening relating to the EGR path  16   a ,  14   a  are both fully open for a predetermined period of time. After this predetermined period of time has expired, the valve  18  begins to be repositioned by the actuator  20  to at least partially close the opening in the housing  12  that relates to the exhaust path  16   b  or relating second opening  14   b.    
     In another alternate embodiment, the valve  18  moves with respect to the openings in the housing  12 , so that the valve  18  begins to be repositioned by the actuator  20  to at least partially close the opening in the housing  12  that relates to the exhaust path  16   b  or relating second opening  14   b  from being in a fully open position when the valve  18  is in a predetermined position with respect to the opening that relates to the EGR path  16   a ,  14   a . Typically, this predetermined valve  18  position with respect to the opening that relates to the EGR path  16   a ,  14   a  is a position where the opening that relates to the EGR path  16   a ,  14   a  is not fully opened. 
     In addition, an alternate embodiment of the air management assembly  24  can include a fail safe for the ETVM  10 ,  10   a ,  10   b ,  10   c  for situations where the actuator  20  malfunctions. When the fail safe is implemented and the actuator  20  malfunctions, the actuator  20  places the valve  18  in a predetermined position. Typically, the predetermined position is where the opening in the housing  12  that relates to the EGR path  16   a ,  14   a  is substantially or fully open, and the opening in the housing  12  that relates to the exhaust path  16   b  or relating second opening  14   b  is partially open. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.