Abstract:
A filter housing that includes a bowl formed with a single thread that is stamped directly into the housing around a port. The thread is used to connect an auxiliary element, such as a drain valve or a WIF sensor, to the filter housing. An elevated ridge is formed around the bowl during the stamping process which increases the structural integrity of the housing around the port, and provides a surface for mating with the inserted auxiliary element.

Description:
FIELD 
       [0001]    A filter housing and a filter assembly that uses the filter housing are described, where the filter housing includes an integrally formed thread on a drain or sensor port. 
       BACKGROUND 
       [0002]    In current filters, auxiliary elements such as water-in-fuel (WIF) sensors and/or drain valves are connected to the filter housing via a crimp nut. The crimp nut is placed in a port in the filter housing, sealant is applied, and the crimp nut is crimped to secure the crimp nut to the filter housing. The auxiliary element is then threaded into the crimp nut, with sealing provided between the auxiliary element and the crimp nut to prevent fluid leaks. However, fluid leakage can occur at the crimp nut seam. In addition, the crimp nut adds additional cost and it requires a separate threaded component attached by an additional process. 
         [0003]    FR2880562 discloses a filter housing that eliminates the crimp nut and instead uses an integrally formed thread to secure a draining/purging valve. 
       SUMMARY 
       [0004]    An improved filter housing is described that includes a single thread which is stamped directly into the housing around a port to connect an auxiliary element to the filter housing. Auxiliary elements that can be used depend upon the specific application of the filter and filter housing, but can include, but are not limited to, drain-valves and WIF sensors. 
         [0005]    The thread can be, for example, a one pitch thread that is formed around the port during a stamping operation on the housing which can be formed of metal. An elevated ridge is formed on the housing around the port during the stamping process which increases the structural integrity of the housing, provides a surface for mating with the inserted auxiliary element, and better allows a single formed thread to be applied to the housing. 
         [0006]    In one embodiment, a filter housing suitable for housing a filter media includes a metal shell having a side wall and a bottom wall connected to the side wall, where the side wall and the bottom wall define an interior space for receiving the filter media. The side wall defines an open end of the filter housing, the bottom wall forms a closed end opposite the open end, and the open end is sized to permit introduction of the filter media into the interior space. A bowl is stamped into the bottom wall or the side wall with the bowl including a port therethrough that places the interior space in communication with an exterior of the filter housing. An integrally formed thread is formed around at least a portion of the port for threaded connection with threads on an auxiliary element for connecting the auxiliary element to the filter housing. 
         [0007]    In addition, the bowl includes a perimeter wall, which in one embodiment can define a seal support surface that extends circumferentially about the perimeter wall. A stamped ridge is integrally formed with the bottom wall or the side wall and that extends at a first end thereof from the perimeter wall and surrounds the bowl. The stamped ridge projects beyond a surface of the bottom wall or the side wall in a direction opposite the bowl to help increase the structural integrity of the bottom wall or the side wall of the housing. 
         [0008]    In another embodiment, a filter assembly is provided that includes the filter housing described herein, a filter media disposed within the interior space of the filter housing, a nut plate attached to the side wall at the open end of the filter housing, an auxiliary element threaded into the port, and a seal disposed between the auxiliary element and the perimeter wall. 
         [0009]    The filter assembly and filter media can be configured for any desired filtering application. One example of a filtering application includes, but is not limited to, a fuel filter assembly for filtering diesel fuel. However, the filter assembly can be used in other applications including, but not limited to, filtering oil, hydraulic fluid, or other applications. 
         [0010]    The described filter housing and filter assembly eliminates the crimp nut and sealant used in some current designs. In addition, the stamped ridge on the filter housing increases the structural integrity of the housing so that the housing meets or exceeds current structural requirements of existing housings. 
         [0011]    In one embodiment, the first end of the thread does not circumferentially overlap the second end of the thread so that a gap is formed therebetween. The gap enhances venting of air from the interior of the filter housing and the drain rate of fluid (when the auxiliary element is a valve) during use. 
     
    
     
       DRAWINGS 
         [0012]      FIG. 1  illustrates a filter assembly employing a filter housing described herein. 
           [0013]      FIG. 2  is a cross-sectional view through a portion of the bottom wall of  FIG. 1  showing details of the stamped bowl. 
           [0014]      FIG. 3  is a perspective view of a portion of the bottom wall of the filter housing of  FIG. 1 . 
           [0015]      FIG. 4  is a cross-sectional view of the stamped bowl in the bottom wall of the filter housing, with the auxiliary element removed. 
           [0016]      FIG. 5  is a cross-sectional view of another embodiment of a filter housing with a domed bottom wall. 
           [0017]      FIG. 6  is a cross-sectional view of another embodiment of a stamped bowl. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    With reference to  FIG. 1 , a filter assembly  10  is illustrated that includes a filter housing  12 , a filter media  14  disposed within the filter housing, and a nut plate  15  that is fixed to the open end of the filter housing. The filter assembly  10  illustrated in  FIG. 1  is configured as a fuel filter assembly for filtering diesel fuel. However, the filter assembly  10  can be configured for any desired filtering application. Examples of other filtering applications include, but are not limited to, an oil filter assembly for filtering oil, a hydraulic filter assembly for filtering hydraulic fluid, and other applications. 
         [0019]    In addition, the filter assembly  10  illustrated in  FIG. 1  is configured to be disposable. However, in other embodiments, the filter assembly can be configured to allow replacement of the filter media  14  in which case the housing  12  would be reused and a detachable lid would be connected to the end of the filter housing (instead of the nut plate  15 ) to allow access to the filter media  14  for removal and replacement of the filter media. 
         [0020]    One or more auxiliary elements  22  are attached to the bottom of the filter housing  12 . The auxiliary element(s) perform functions based on the particular application of the filter assembly. In the illustrated embodiment, two auxiliary elements  22   a,    22   b  are attached to the filter housing. But as illustrated in  FIG. 5 , a single auxiliary element  22   a  can be attached to the housing. The functions of the auxiliary element(s) include, but are not limited to, sensing a condition within the filter housing  12  and/or draining fluid from the filter housing. 
         [0021]    In the illustrated example, the filter media  14  is configured as a fuel-water separator media that is configured to separate water from fuel. Fuel-water separator media is well known in the art. The media  14  is generally ring-shaped defining a central cavity  16 , with a first or upper endplate  18  attached to the upper end of the media  14  and a second or bottom endplate  20  attached to the lower end of the media  14 . This configuration of the media is also well known in the art. 
         [0022]    Water that is separated from the fuel by the media  14  collects at the base of the housing  12  and needs to be drained from the housing  12 . In this case, the auxiliary element  22   a  comprises a drain valve, for example a manual drain valve, which is configured to drain water from the filter housing. The auxiliary element  22   b  is a WIF sensor that is configured to sense accumulation of water within the filter housing and to generate a warning signal when enough water accumulates. 
         [0023]    The filter housing  12  is formed by a metal shell having a side wall  30  and a bottom wall  32  connected to the side wall. The side wall  30  and the bottom wall  32  define an interior space  34  that is use receives the filter media  14 . The side wall defines an open end  36  of the filter housing, and the nut plate  15  is attached to the open end  36 , while the bottom wall  32  forms a closed end opposite the open end. The open end  36  is sized to permit introduction/removal of the filter media  14  into the interior space  34  during assembly, after which the nut plate  15  is attached. The bottom wall  32  in  FIG. 1  is illustrated as being generally flat. However, as illustrated in  FIG. 5 , the filter housing can use a dome-shaped bottom wall  40  as well. 
         [0024]    With reference to  FIGS. 2-4 , the mounting of the auxiliary elements  22   a,    22   b  to the filter housing  12  will now be described. The auxiliary elements are illustrated as being mounted to the bottom wall  32 . However, in some embodiments, one or more of the auxiliary elements can be mounted to the side wall  30  in which case the auxiliary element(s) would be mounted in the same manner as discussed below. In addition, the auxiliary elements  22   a,    22   b  are mounted in the same manner, so only the mounting of the auxiliary element  22   a  will be discussed in detail below. 
         [0025]    As shown in  FIGS. 2-4 , a bowl  50  is stamped into the bottom wall  32 . The bowl  50  projects or extends in a direction into the interior space  34  of the housing  12 . However, in some embodiments, the bowl  50  can project or extend in a direction away from the interior space so that the bowl  50  is disposed outside of the interior space of the housing. 
         [0026]    The bowl  50  includes a port  52  therethrough that places the interior space  34  in communication with the exterior of the filter housing. In the illustrated embodiment, the port  52  has an axis that is parallel to a longitudinal axis A-A of the filter housing  12 . However, the axis of the port can be at any angle to the longitudinal axis, including perpendicular when the auxiliary element is mounted to the side wall of the housing. 
         [0027]    A thread  54  is integrally formed on the bowl  50  around at least a portion of the port  52  for threaded connection with threads  56  on the auxiliary element  22   a  for detachably connecting the auxiliary element  22   a  to the bottom wall  32 . The thread  54  can be a one pitch thread that is created at the same time as the bowl  50  in a stamping operation to form the bowl. 
         [0028]    The bowl  50  further includes a circumferentially extending perimeter wall  58  that has a first end  60  connected to the thread  54  and a second end  62  that is connected to a stamped ridge  64  that can also be created in the same stamping operation as the bowl. The perimeter wall  58  includes a seal support surface  66  that extends circumferentially about the perimeter wall. As best seen in  FIGS. 2 and 4 , the seal support surface  66  is axially spaced from the integrally formed thread  54  in the direction of the longitudinal axis and is disposed between the integrally formed thread  54  and the stamped ridge  64 . As shown in  FIG. 4 , the seal support surface  66  has a portion  68  that extends in a radial direction perpendicular to the longitudinal axis A-A to support an end of a seal  70  and prevent the seal from interfering with the threads  54 ,  56 . 
         [0029]    The stamped ridge  64  is integrally formed with the bottom wall  32  and increases the structural integrity of the bottom wall around the bowl  50 . The ridge  64  projects beyond an outer surface  80  of the bottom wall  32  in a direction opposite the bowl  50  (in the illustrated embodiment, the ridge  64  projects in a direction away from the interior space  34 ), and surrounds the bowl. 
         [0030]    The ridge  64  includes a first end  82  thereof that is connected to and extends from the end  62  of the perimeter wall, and a second end  84  that connects to the remainder of the bottom wall  32 . With reference to  FIG. 4 , a horizontal plane B-B that extends through where the first end  82  of the ridge  64  connects to the end  62  and through where the second end  84  connects to the remainder of the bottom wall, and that is perpendicular to the longitudinal axis A-A, does not extend through the perimeter wall  58 . 
         [0031]    With reference to  FIGS. 3 and 4 , the thread  54  has a first terminal end  90  and a second terminal end  92 . The first and second ends  90 ,  92  do not circumferentially overlap which creates a gap  94  between the ends  90 ,  92 . The gap  94  enhances venting of air from the interior of the filter housing  12  and the drain rate of fluid (when the auxiliary element is a valve) during use. This gap  94  need not be formed when the auxiliary element is a WIF sensor. 
         [0032]    Turning to  FIG. 2 , the seal  70  is illustrated as being an o-ring seal having a generally pill-shaped cross-section. The filter housing  12  and the auxiliary element  22   a  can be configured such that the seal  70  forms face seals  100 ,  102  with the auxiliary element and the perimeter wall, and the seal  70  forms radial seals  104 ,  106  with the auxiliary element and the perimeter wall  58 . In particular, the seal  70  has a first portion engaged with and supported by the radial portion  68  of the seal support surface  66  to form the face seal  102 , and a second portion in sealing engagement with a radially extending portion  110  of the auxiliary element  22   a  to form the face seal  100 . In addition, the seal  70  has a portion engaged with an axially extending, radially outward facing surface  112  of the auxiliary element to form the radial seal  104 , and a portion engaged with the interior, radially inward facing surface of the perimeter wall  58  to form the radial seal  106 . However, the filter housing, the auxiliary element and/or the seal can have any configurations that are suitable for achieving these various seals. 
         [0033]    As also illustrated in  FIG. 2 , the radially extending portion  110  of the auxiliary element  22   a  abuts against the stamped ridge  64  when fully installed. This helps to form a stop for the auxiliary element to limit insertion of the auxiliary element. 
         [0034]      FIG. 6  illustrates another embodiment of a bowl  150  that is stamped into a bottom wall  132  of a filter housing. The bowl  150  is similar to the bowl  50  in that the bowl  150  includes a port  152 , an integrally formed thread  154 , a perimeter wall  158 , and a stamped ridge  164  that increases the structural integrity of the bottom wall around the bowl  150 . 
         [0035]    In this embodiment, the bowl  150  does not project into the interior space of the housing as much as the bowl  50 . Instead, this embodiment relies on a gasket seal  170  that is pressed into engagement with the stamped ridge  164  by a radially extending portion  180  of an auxiliary element  122  (only a portion of which is shown in  FIG. 6 ) that is threaded into the port  152 . 
         [0036]    The invention may be embodied in other forms without departing from the spirit or novel characteristics thereof. The embodiments disclosed in this application are to be considered in all respects as illustrative and not limitative. The scope of the invention is indicated by the appended claims rather than by the foregoing description; and all changes which come within the meaning and range of equivalency of the claims are intended to be embraced therein.