Abstract:
A filter assembly where the filter element is designed to connect directly to the spud of a vehicle fluid system, for example an engine lubrication system, a fuel system, or a hydraulic system. This provides a direct connection between the filtered fluid and the fluid system. The need for a seal between the top endplate and the nutplate, as well as the coil spring within the shell, which are found in conventional spin-on filter assemblies can be eliminated, which reduces inventory and the number of parts forming the filter assembly, and facilitates manufacturing of the filter assembly.

Description:
FIELD 
       [0001]    This disclosure relates generally to fluid filtration, and particularly, but not by way of limitation, to the design of a filter assembly that includes a filter element intended to connect directly to the engine. 
       BACKGROUND 
       [0002]    A known type of fuel and oil filter includes a shell, a nutplate secured to the shell, and a filter element disposed within the shell. The nutplate includes a threaded aperture through which filtered fluid exits the filter, and which engages with threads on an engine spud to secure the filter to the engine. Filtered fluid that exits the filter through the aperture flows into the engine spud and to the engine. This type of filter is sometimes referred to as a spin-on filter. 
         [0003]    In a spin-on filter, an inner elastomeric sealing member is typically provided between the nutplate and a top endplate of the filter element to prevent bypass of fluid around the filter from the unfiltered fluid side to the filtered fluid side. A coil spring is also typically provided between the base of the shell and the bottom of the filter element to bias the filter element upwardly into engagement with the nutplate and enhance the seal between the nutplate and the filter element. However, if the inner sealing member is not installed correctly or the spring does not seat properly against the filter element, an internal bypass situation can result whereby unfiltered fluid can bypass the filter. If this occurs, unfiltered fluid can flow to the engine which can lead to increased engine wear and damage. 
       SUMMARY 
       [0004]    A vehicle filter assembly is described where the filter element is designed to connect directly to the spud of a vehicle fluid system, for example an engine lubrication system, a fuel system, or a hydraulic system. This provides a direct connection between filtered fluid and the fluid system. In the case of a spin-on filter, the need for a seal between the top endplate and the nutplate, as well as the coil spring within the shell, can be eliminated which reduces inventory and the number of parts forming the filter assembly, and facilitates manufacturing of the filter assembly. 
         [0005]    In one embodiment, a filter element includes filter media suitable for filtering a fluid, such as oil, fuel, or hydraulic fluid. The filter media has a first end and a second end, and defines an inner region that is surrounded by the filter media. A top endplate is secured to the first end of the filter media and a bottom endplate is secured to the second end. The top endplate includes an opening therein that is in fluid communication with the inner region and a sleeve extending from the opening to an open end thereof. The sleeve defines a fluid flow passageway from the opening to the open end. The sleeve includes structure suitable for securing the sleeve directly to a spud of an engine fluid system. For example, the sleeve includes an inner surface defining the fluid flow passageway, and at least a portion of the inner surface adjacent the open end of the sleeve is threaded. The threads are used to connect the filter element directly to the fluid system spud. The bottom endplate is solid without any fluid flow passageways. 
         [0006]    The filter element forms part of a filter assembly that includes a shell having an interior space that receives the filter media of the filter assembly, and a retainer or nutplate secured to an open end of the shell. The retainer is secured to the top endplate, and the sleeve of the top endplate extends through the retainer to permit the open end to communicate with an exterior of the filter assembly. 
         [0007]    In addition to being directly secured to the spud, the top endplate includes structure that is engaged with structure on the retainer that prevents relative rotation between the top endplate and the retainer during installation and removal of the filter assembly from the spud. In addition, a snap-lock connection between the top endplate and the retainer secures the top endplate to the retainer. 
     
    
     
       DRAWINGS 
         [0008]      FIG. 1  is an exploded perspective view of the elements of the filter assembly described herein. 
           [0009]      FIG. 2  is a cross-sectional side view of the assembled filter assembly. 
           [0010]      FIG. 3  is a cross-sectional side view of the filter element of the filter assembly. 
           [0011]      FIG. 4  is a perspective view of the retainer of the filter assembly. 
           [0012]      FIG. 5  is a perspective view of the top endplate of the filter element. 
           [0013]      FIG. 6  is a perspective view of an alternative embodiment of a top endplate. 
           [0014]      FIG. 7  is a perspective view of an alternative embodiment of a retainer used with the top endplate of  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    With reference to  FIG. 1 , a filter assembly  10  is illustrated that includes a shell  12 , a  10  filter element  14 , and a retainer  16 . As described using an exemplary embodiment below, the filter element  14  is designed to connect directly to a conventional spud of a vehicle fluid system. The filter assembly  10  receives fluid to be filtered, filters the fluid, and directs filtered fluid back to the fluid system. The vehicle fluid system can be any fluid system on a vehicle, for example an engine lubrication system, an engine fuel system such as a diesel fuel system, or a hydraulic system. The term “fluid” as used in this disclosure and the claims is considered to encompass vehicle fluids including, but not limited to, lubrication oil, fuel including diesel fuel, hydraulic fluid, etc. Thus, the filter assembly  10  can be variously called an oil filter assembly, a fuel filter assembly, a hydraulic fluid filter assembly, etc. depending upon the type of fluid to be filtered by the filter assembly. Preferably, the filter assembly  10  is used as an oil or fuel filter assembly on a diesel engine. 
         [0016]    With reference to  FIGS. 1 and 2 , the shell  12  has a substantially cylindrical sidewall  20 , a base portion  22  integral with the sidewall that forms a closed end of the shell  12 , an open end  24 , and an interior space  26  defined by the sidewall  20  and the base portion  22 . In the illustrated embodiment, the shell  12  is generally cylindrical in shape, although in appropriate circumstances the shell  12  could have different shapes. The shell  12  is formed of any material that is suitable for forming a shell on a filter assembly, for example steel. In appropriate circumstances the shell  12  could be formed of a non-metallic material such as a plastic or a composite. 
         [0017]    The retainer  16  is fixed to the open end  24  of the shell  12  and substantially closes the open end. Referring to  FIGS. 1 ,  2  and  4 , the retainer  16 , which can also be referred to as a nutplate, is a cylindrical, ring-shaped member with an outer peripheral surface  30  having a circumferential retention groove  32 . The upper end of the sidewall  20  is formed with a bead  34  that fits within the groove  32 . The bead  34  can then be secured to the groove  32  in known manner to prevent relative rotation between the shell  12  and the retainer  16 . For example, the bead  34  can be staked to the groove  32 . 
         [0018]    The retainer  16  also includes a central opening  36  for receiving a portion of the filter element  14  as described further below. A plurality of inlet fluid flow openings  38  are formed through the retainer  16  surrounding the opening  36  through which fluid to be filtered enters the filter assembly  10 . A gasket groove  40  is formed in the top surface of the retainer  16 , and a rectangular elastomeric gasket  42  seats in the groove  40  for sealing with a surface surrounding the spud. 
         [0019]    The retainer  16  is formed of any material that is suitable for forming a nutplate on a spin-on filter assembly, for example a metal such as aluminum, or a non-metallic material such as a plastic or a composite. 
         [0020]    Returning to  FIG. 1 , the filter element  14  includes a ring of pleated filter media  50 , a bottom end plate  52  and a top end plate  54 . The filter media  50  can be any filter media that is suitable for filtering the fluid with which the filter assembly  10  is to be used. Many types of filter media exist, and a person of ordinary skill in the art would know the appropriate filter media to use. 
         [0021]    As used herein, a ring of filter media is any endless filter media that bounds an area. As evident from.  FIG. 1 , the filter media  50  forms a generally circular ring. The media  50  is disposed around a perforated center tube  56  which helps retain the circular shape of the media. When the filter assembly  10  is assembled, an unfiltered fluid region  58  is defined between the inner surface of the shell  12  and the outer circumference of the filter media  50 , while a filtered fluid or inner region  60  is defined by the inner space within the center tube  56  and the inner perimeter of the filter media. Thus, the filter element  14  in the illustrated embodiment is designed for outside-in flow of fluid. However, in other embodiments, the filter element could be designed for inside-out fluid flow. 
         [0022]    As best seen in  FIG. 3 , the filter media  50  includes a first end  62  that is secured to the top endplate  54 , and a second end  64  that is secured to the bottom endplate  52 . The endplates  52 ,  54  are preferably formed from a non-metallic material such as plastic or composite, but could be also formed of metal. Any suitable means for securing the ends  62 ,  64  to the endplates  54 ,  52  can be used including, but not limited to, adhesive or embedding the media into the endplates. 
         [0023]    The bottom endplate  52  is illustrated as being a solid plate without any fluid flow passageways which closes off the bottom end of the filter media  50  and prevents filtered fluid from exiting through the bottom of the filter element. However, in certain filters, such as lube filters, one or more bypass valves can be provided in the bottom endplate and/or other openings can be provided that allow fluid flow through the bottom endplate. 
         [0024]    The top endplate  54 , which is best seen in  FIGS. 3 and 5 , includes a ring-shaped flange  70  to which the first end  62  of the filter media  50  is secured. An opening  72  is formed in the endplate  54  surrounded by the flange  70 . A cylindrical sleeve  74  extends upwardly from the opening  72  to an open end  76 , and a fluid flow passageway  78 , defined by an inner surface  80  of the sleeve, extends from the opening  72  to the open end  76 . At least a portion of the inner surface  80  adjacent the open end  76  is threaded  82 . The threads  82  are used to connect the filter assembly  10  to the spud. In the illustrated embodiment, the threads  82  extend from the open end  76  downward approximately one-third of the length of the inner surface  80 . Structure other than threads  82  that one finds suitable for securing the sleeve directly to a spud of a vehicle fluid system can be used, for example a snap-fit connection structure. 
         [0025]    There is structure engaged between the top endplate  54  and the retainer  16  that prevents relative rotation therebetween when the elements are assembled. For example, as best seen in  FIG. 5 , an outside surface  90  of the sleeve  74  includes a plurality of anti-rotation members  92  at spaced locations around the sleeve. In the illustrated embodiment, a pair of members  92  are provided at diametrically opposed locations on the outside surface  90 , with the members  92  being identical in construction. Other numbers of members  92  can be used. The members  92  are illustrated as comprising protrusions projecting from the outside surface  90 , but other forms of anti-rotation members can be used. With reference to  FIG. 4 , the retainer  16  includes a plurality of anti-rotation members  94  that are configured to engage with the anti-rotation members  92 . The members  94  comprise diametrically opposed slots formed in the retainer that are designed with a shape generally complementary to the members  92  so as to receive the members  92  therein. 
         [0026]    When the endplate  54  and the retainer  16  are brought into engagement as discussed further below, the members  96  will receive the members  94  therein. The shapes of the members  94 ,  96  will prevent relative rotation between the endplate  54  and the retainer  16 . 
         [0027]    In addition, there is structure axially securing the top endplate  54  and the retainer  16 . In the illustrated embodiment, the structure comprises a snap-lock connection between the top endplate and the retainer. More particularly, with reference to  FIGS. 2 and 5 , a plurality of snap-lock tabs  100  are formed on the outside surface  90  of the sleeve in the gaps between the anti-rotation members  92 . In addition, the retainer  16  is provided with snap-lock members  102  that are designed to engage with the snap-lock tabs  100 . When the endplate  54  and the retainer are brought into engagement as discussed further below, the snap-lock members  102  will be deflected outwardly by the snap-lock tabs  100 , until the members  102  clear the tabs  100  at which point the members  102  will deflect back to the position shown in  FIG. 2  behind the tabs  100 . The tabs  100  and the members  102  will prevent axial removal of the endplate  54  and the retainer  16  once they are engaged. 
         [0028]      FIGS. 6 and 7  illustrate an alternative embodiment of a top endplate  150  and a retainer  152  utilizing different anti-rotation structure and axial securement structure. The top endplate  150  includes a sleeve  160  with a plurality, for example four (only three being visible in  FIG. 6 ), of triangular shaped anti-rotation members  162  in the form of protrusions. The retainer  152  includes a plurality, for example four, triangular shaped slots  164  that receive the members  162  therein when the endplate  150  and the retainer  152  are brought into engagement. Axial securement is provided by snap-lock tabs  170  formed on the anti-rotation members  162 , and snap-lock members  172  associated with each slot  164 . Each snap-lock member  172  includes a window  174  that is designed to receive a corresponding snap-lock tab  170  therein for axially fixing the endplate and the retainer when the endplate  150  and the retainer  152  are brought into engagement. 
         [0029]    Although the number of snap-lock tabs is illustrated as corresponding to the number of anti-rotation members, any number of snap-lock tabs and anti-rotation features can be used as long as the functions of anti-rotation and axial securement between the top endplate and the retainer are achieved. 
         [0030]    The construction and operation of the filter assembly  10  will now be described. The filter element  14  is first assembled, with the filter media  50  being disposed around the center tube  56  and the ends  62 ,  64  of the filter media being secured to the endplate  54 ,  52 . The retainer  16  and the filter element  14  are then brought together, with the sleeve  74  of the top endplate  54  being inserted through the central opening  36  of the retainer. The sloped sides of the anti-rotation members and the anti-rotation slots will help achieve correct alignment of the top endplate and the retainer, as well as align the snap-lock axial securement features. When the retainer and the top endplate are aligned correctly, the retainer and the top endplate are snapped together. 
         [0031]    The connected filter element and retainer are then installed into the shell  12 . The bead  34  of the shell  12  is formed in the groove  32 , and the shell  12  is locked to the retainer  16  by, for example, staking the bead  34  in the groove  32 . The rectangular gasket  42  is then installed into the gasket groove  40 . 
         [0032]    The assembled filter assembly  10  is shown in  FIG. 2 . The filter assembly is installed by threading the threaded sleeve  74  of the filter element  14  onto the threaded spud of the fluid system. During installation (as well as removal of the filter assembly) onto the spud, the anti-rotation members  92 ,  94  prevent relative rotation between the retainer and the filter element. In addition, the securement of the shell  12  to the groove  32  prevents relative rotation between the shell and the retainer  16 . 
         [0033]    When installed, fluid to be filtered enters the filter assembly via the flow openings  38  in the retainer, flows down to above the flange  70  of the top endplate, and around the edges of the flange  70  to the unfiltered fluid region  58 . The fluid then flows through the filter media  50  which filters the fluid. The filtered fluid then reaches the filtered fluid region  60 , flows upwardly through the opening  72 , into the fluid flow passageway  78  through the sleeve  74  and out the sleeve into the spud for return to the fluid system. 
         [0034]    The disclosed filter assembly  10  eliminates the need for a seal between the top endplate and the retainer since the return flow path of the sleeve  74  is directly connected to the fluid system spud. In addition, since the filter element is directly connected to the spud, a coil spring as found in conventional spin-on filters that biases the filter element upwardly into engagement with the nutplate is no longer required. 
         [0035]    The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.