Abstract:
Fluid filter elements and assemblies are used to separate contaminants from a fluid, such as oil or fuel, prior to reaching an engine. Fluid filter assemblies may comprise a housing, a filter element, and a filter head. The Filter element may be disposed within the filter housing and enclosed by the filter head. Fluid enters the housing and passes through the filter element. The fluid may then exit the assembly. A connector may be used to connect the filter element to the filter head to ensure proper installation and simplify removal of a fouled filter element. The connector permits removable coupling of the filter element to the filter head and resists unintentional disengagement to securely couple the filter element to the filter head.

Description:
DISCLOSURE OF THE INVENTION 
       [0001]    The invention relates to filter elements and assemblies used to separate contaminants from a fluid, such as oil or fuel, prior to reaching an engine. Fluid filter assemblies may comprise a housing, a filter element, and a filter head. The filter element may be disposed within the filter housing and enclosed within the housing by the filter head. Fluid enters the housing and passes through the filter element. The filter element has a filter medium through which the fluid passes. The filter medium restricts the passage of contaminants of a particular size from flowing through the filter medium. 
         [0002]    As the filter element collects contaminants over time, it becomes more difficult for fluid to pass through the filter element. Thus, filter elements have a useful life and require replacement. A connector may be used to connect the filter element to the filter head to ensure proper installation and simplify removal of a fouled filter element. The connector permits removable coupling of the filter element to the filter head and resists unintentional disengagement to securely couple the filter element to the filter head. 
         [0003]    In particular, the present invention relates to a filter element for separating impurities from a fluid. The filter element comprises a filter medium and an end cap. The filter medium may have an end. The end cap may be coupled to the end of the filter medium and may include a filter head connector configured to removably connect the filter element to a filter head. The filter head connector may have a release portion and a retainment portion. The release portion may permit axial movement between the filter head connector and the filter head, and the retainment portion may substantially prevent disengagement of the filter head connector from the filter head. The filter head connector may resist rotational movement between the filter head and the filter head connector from the retainment portion to the release portion. 
         [0004]    In accordance with another aspect of the invention, the filter element may comprise a filter medium and an end cap. The filter medium may have an end. The end cap may be coupled to the end of the filter medium and may include a connector and a base. The connector may have a proximate end near the base, a distal end spaced from the base, a guide surface, and a recessed surface. The guide surface may extend the entire length of the connector from the distal end to the proximate end, and at least a portion of the guide surface may angle outward from the distal end toward the proximate end. The recessed surface may be disposed adjacent to the guide surface. 
         [0005]    In accordance with another aspect of the invention, the filter element may comprise a filter medium and an end cap. The filter medium may have a generally cylindrical configuration and may include an end. The end cap may be coupled to the end of the filter medium and may include a connector. The connector may extend away from the filter medium and may include a distal end, a guide surface, an abutment which is circumferentially spaced from the guide surface, and a recessed surface which extends circumferentially from the guide surface to the abutment. At least a portion of the guide surface may have a slope which angles radially outward from a first region near the distal end to a second region spaced from the distal end, and the recessed surface may be spaced radially inward from the second region of the guide surface the entire circumferential distance between the guide surface and the abutment. 
         [0006]    The present invention also relates to a filter assembly for separating impurities from a fluid. The filter assembly may comprise a filter housing and a filter element. The filter housing may include a filter head having a connector extension. The filter element may include a filter medium having an end and an end cap coupled to the end of the filter medium. The end cap may include a connector having a release portion and a retainment portion. The filter element may be removably connectable to the filter head by slidingly engaging the release portion with the connector extension and rotating the connector and the filter head relative to one another to engage the connector extension with the retainment portion. In other embodiments, the filter element may include the connector extension and the filter head may include the connector. 
         [0007]    In accordance with another aspect of the invention, the filter assembly may comprise a filter housing and a filter element. The filter housing may include a filter head having a connector extension. The filter element may include a filter medium having an end and an end cap coupled to the end of the filter medium. The end cap may include a connector having a recessed surface. The connector extension may be removably received in the recessed surface by relative rotational movement between the connector and the filter head. A retainer may be configured to retain the connector extension in the recessed surface. In other embodiments, the filter element may include the connector extension and the filter head may include the connector. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a cross-sectional view of a filter assembly; 
           [0009]      FIG. 2  is an exploded view of the filter assembly of  FIG. 1 ; 
           [0010]      FIG. 3  is a perspective view of a filter head connector; 
           [0011]      FIG. 4  is a top plan view of the filter head connector of  FIG. 3 ; 
           [0012]      FIG. 5  is a cross-sectional view taken through line  5 - 5  of the filter head connector of  FIG. 4 ; 
           [0013]      FIG. 6  is a cross-sectional view taken through line  6 - 6  of the filter head connector of  FIG. 4 ; 
           [0014]      FIG. 7  is a bottom view of a filter head disc member; 
           [0015]      FIG. 8  is an exploded perspective view of the filter head disc member of  FIG. 7  and the filter head connector of  FIG. 3 ; 
           [0016]      FIG. 9  is a perspective view showing the filter head cap of  FIG. 7  and the filter head disc member of  FIG. 3  before rotation into the secured orientation; and 
           [0017]      FIG. 10  is a perspective view showing the filter head disc member of  FIG. 7  and the filter head connector of  FIG. 3  rotated relative to one another into the secured orientation. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    Turning to the figures, wherein like shown or described features may represent like elements, a fluid filter assembly  100  for separating contaminates from a fluid is shown in  FIG. 1 . The fluid filter assembly  100  is disposed such that prior to a fluid reaching an engine, such as fuel or oil, contaminants may be removed from the fluid. The fluid filter assembly  100  may comprise a housing  102 , a filter head  104 , and a filter element  106 . As will be described in further detail below, the filter element  106  may be disposed within the housing  102  and enclosed within the housing  102  by the filter head  104 . The filter element  106  generally has a limited useful life before contaminants filtered by the filter element  106  accumulate in the filter medium  108  of the filter element  106  to a sufficient extent to undesirably restrict the passage of fluid therethrough and increase the pressure drop across the filter element  106 . Thus, the filter element  106  is removably connectable to the filter head  104  such that a fouled filter element  106  can be detached from the filter head  104  for disposal and replaced with a new filter element  106 . 
         [0019]    The housing  102  may comprise a body  110  having a generally cylindrical interior surface  112  and an open mouth  114  for receiving the filter element  106 . The housing  102  may also comprise a fluid inlet  116  whereby the fluid is received into the housing  102  for filtering. The housing  102  may further comprise a threaded surface  118  disposed near the open mouth  114  for receiving and securely coupling the filter head  104  to the housing  102 . 
         [0020]    The filter head  104  similarly may comprise a threaded surface (not shown) for engaging the threaded surface  118  of the housing  102  such that the filter head  104  may be securely coupled to the housing  102  by rotating the filter head  104  relative to the housing  102 . In other embodiments, such as shown in  FIG. 1 , the filter head  104  may have a securement flange  120  around the perimeter of the filter head  104 . A coupling ring  122  may be provided having threads  124  for rotationally engaging the threads  118  on the housing  102 . When the coupling ring  122  is disposed over the filter head  104 , the coupling ring  122  grips the securement flange  120 . As the coupling ring  122  is rotated, it clamps the securement flange  120  to the housing  102 . A seal  126  may be disposed between the filter head  104  and the housing  102  to prevent leakage and maintain the pressure within the filter assembly  100 . 
         [0021]    Referring to  FIGS. 1 and 7 , the filter head  104  may comprise a fluid outlet  128  for permitting the flow of filtered fluid to exit the housing  102  and proceed to the engine. An outlet feeder tube  130 , which fluidly communicates with the fluid outlet  128 , may extend from the filter head  104  for insertion into the interior of the filter element  106 . The outlet feeder tube  130  transports filtered fluid from the interior of the filter element  106  to the fluid outlet  128 . As shown in  FIG. 1 , the outlet feeder tube  130  may have an elongate generally cylindrical configuration with an aperture  144  disposed therethrough to permit fluid to flow through the outlet feeder tube  130 . 
         [0022]    The filter head  104  may further comprise an extension member  132  extending from the filter head  104 . The extension member  132  may comprise an elongate body projecting outward from the filter head  104 . The extension member  132  comprises a proximal end  134  near the filter head  104  and a distal end  136  disposed away from the filter head  104 . A shaped end  138  may be disposed near the distal end  136  of the extension member  132  for engaging the filter element  106 . The shaped end  138  may have a generally semi-circular cross-sectional shape. It will be appreciated, however, that the extension member  132  and shaped end  138  may have any suitable shape and/or size. 
         [0023]    The filter head  104  may further comprise one or more spacers  140  extending from the filter head  104 . Similar to the extension member  132 , the spacer  140  may have an elongate body. The spacers  140  help to maintain a minimum distance between the filter head  104  and the filter element  106 . 
         [0024]    The extension members  132 , the spacers  140 , and the outlet feeder tube  130  may project directly from the filter head  104 , or in other embodiments, as shown in FIGS.  1  and  7 - 10 , they may project from a filter head disc member  146 . The filter head disc member  146  is securely attached to the filter head  104  in any suitable manner. For purposes of explanation, however, the filter head disc member  146  is shown in  FIGS. 7-10  as separated from the filter head  104 . The filter head disc member  146  may have a surface  148  that the extension members  132  and spacers  140  extend therefrom. The outlet feeder tube  130  may be centrally disposed on the filter head disc member  146  and extends through the filter head disc member  146 . 
         [0025]    Turning to  FIG. 2 , the filter element  106  comprises a generally cylindrical body having a first end  150  and a second end  152 . The second end  152  of the filter element  106  may be removably attachable to the filter head  104 . The first end  150  of the filter element  106  may be disposed near the base  154  of the housing  102  when inserted into the housing  102 . It will be appreciated that the filter element  106  may be of any suitable shape and size. It will also be appreciated that the filter element  106  may be constructed in any suitable manner. 
         [0026]    The filter element  106  comprises a filter medium  108 . The filter medium  108  permits fluid to flow therethrough while restricting the passage of contaminants. The filter medium  108  may be pleated to enhance the strength of the filter medium  108  and increase the amount of surface area of the filter medium  108  exposed to the fluid. The pleats may extend inwardly or outwardly in a radial direction or in a curved, arcuate, angled, or straight non-radial direction. The filter medium  108  may be of any suitable shape and may be constructed of any suitable material including, but not limited to, a permeable or semipermeable membrane or a fibrous sheet, including being constructed of materials such as metal, natural or synthetic polymers, or a ceramic or glass. Further, it will be appreciated that the filter medium  108  may have any suitable number of layers and/or additional layers, such as drainage layers or cushioning layers, may be pleated with the filter medium  108 . 
         [0027]    The filter element  106  may comprise a core and/or cage (not shown) disposed on the interior and/or exterior surface of the filter element  106 . The core and/or cage may extend from the first end  150  of the filter element  106  to the second end  152  of the filter element  106  and may be at least partially cylindrical to abut at least a portion of the interior or exterior of the filter medium  108 , respectively. The core and/or cage, if present, comprise a structure suitable to permit the passage of fluid therethrough. For example, the core and/or cage may comprise a plurality of apertures to permit fluid to flow therethrough. The core and/or cage may provide support to the filter element to resist forces exerted thereon during the filtration process. 
         [0028]    The filter element  106  may comprise a first end cap  156  disposed at the first end  150  of the filter element  106  and a second end cap  158  disposed at the second end  152  of the filter element  106 . The end caps  156 ,  158  may abut and encompass the respective ends  150 ,  152  of the filter medium  108 . The end caps  156 ,  158  may be bonded to the filter medium  108 . For example, the end caps  156 ,  158  may be heat bonded or adhesively bonded to the ends of the pleated filter medium  108 . However, it will be appreciated that the end caps  156 ,  158  may be secured to the filter medium  108  in any suitable manner. In some embodiments, the filter element  106  may not have an end cap or may have only a single end cap. 
         [0029]    As shown in  FIGS. 3-6 , the second end cap  158  may comprise an aperture  160  to permit filtered fluid to exit the interior  142  of the filter element  106  through the aperture  160  and into the filter head  104 . The fluid can then exit the filter assembly  100  through the fluid outlet  128  in the filter head  104 . This may be accomplished via the outlet feeder tube  130  which may project through the aperture  160  and into the interior  142  of the filter element  106  when the filter element  106  is attached to the filter head  104 . As shown in  FIG. 1 , a seal  162  may be disposed between the second end cap  158  and the outlet feeder tube  130  to prevent the contamination of the filtered fluid with unfiltered fluid and to maintain the pressure differential between inside the filter element  106  and outside the filter element  106 . 
         [0030]    The filter element  106  may be releasably secured to the filter head  104 . As mentioned above, filter elements  106  have a finite useful life, and thus, require replacement when the useful life has expired. Therefore, an advantage of being able to releasably secure the filter element  106  to the filter head  104  is that after the filter housing  102  is removed from the filter head  104 , a spent filter element  106  may be easily removed from the filter head  104  and a new filter element  106  may be readily installed on the filter head  104 . 
         [0031]    The filter element  106  may be securely attachable to the filter head  104  such that it does not unintentionally detach from the filter head  104 . As shown in  FIGS. 1 and 2 , in order to securely couple the filter element  106  to the filter head  104 , the filter element  106  may comprise a filter head connector  164 . The filter head connector  164  may be formed as part of an end cap, such as  158 , or may be attached to an end cap. Referring to  FIGS. 3-6 , the filter head connector  164  may comprise a base  166  and a generally cylindrical connector portion  168 . The base  166  may be disc-shaped and may extend radially from a proximal end  170  of the connector portion  168 . The base  166  forms part of or is connected to the second end cap  158 . As discussed in further detail below, the connector portion  168  may be engaged by the extension member  132  of the filter head  104  to couple the filter element  106  to the filter head  104 . For simplification and for purposes of discussion, the filter head connector  164  and second end cap  158  are shown and described as essentially the same component, however, it will be appreciated that the filter head connector may be a separate component coupled to the end cap as mentioned above. Therefore, references and discussion directed to the filter head connector  164  or the second end cap  158  may be applicable to the other. 
         [0032]    The connector portion  168  may comprise a guide surface  174 , a recessed portion  176 , a locking portion  178 , and an abutment  180 . The guide surface  174  may begin near a distal end  172  of the connector portion  168  and may ramp outward from the distal end  172  to the proximal end  170  such that the diameter of the guide surface  174  is larger near the proximal end  170  than the distal end  172 . The ramped portion of the guide surface  174  may level out into a rest  186  near the proximal end  170 . The recessed portion  176  is disposed circumferentially adjacent to the guide surface  174  near the proximal end  170  with a rounded ridge  182  disposed therebetween. The rounded ridge  182  is discussed in further detail below. 
         [0033]    The abutment  180  extends radially outward from the connector portion  168  a distance sufficient to act as a stop to prevent the extension member  132  from rotating beyond the abutment  180 . A similar guide abutment  184  may be disposed near the guide surface  174 . The guide abutment  184  may circumferentially oppose the abutment  180  to provide a rotational restriction for the extension member  132  and may operate in combination with the guide surface  174  to provide a discrete path of a desired width for the extension member  132  to slidingly engage the connector portion  168 . 
         [0034]    The locking portion  178  and the recessed portion  176  are disposed axially relative to one another along the connector portion  168  such that a hard transition is formed therebetween. The hard transition is formed by the difference in outer diameters between the recessed portion  176  and the locking portion  178  resulting in a ledge  188  because the recessed portion  176  is smaller in diameter. Unlike the rounded ridge  182  between the recessed portion  176  and the guide surface  174 , the ledge  188  between the recessed portion  170  and locking portion  178  may be disposed at right angles relative to the recessed portion  176  and locking portion  178 . 
         [0035]    Referring still to  FIGS. 3-6 , the connector portion  168  may comprise one or more retainers or clips  190 . Each clip  190  may be arcuate in shape and may have a radius such that the clip runs generally parallel to the connector portion  168 . The clip  190  may be coupled to the connector portion  168  along the distal half of the connector portion  168  and axially adjacent to the abutment  180 . The clip  190  may include a circumferentially extending arm  191  that may be connected to the connector portion  168  at one end and at the other end may comprise a half-arrowhead shaped end  192 . The shaped end  192  may not be directly coupled with the connector portion  168 , but instead may be radially spaced away from the connector portion  168  to form a gap therebetween. As shown in  FIG. 4 , the half-arrowhead shaped end  192  may have a lead-in edge  194  and a backside edge  196  for contacting the extension member  132 . It will be appreciated that any suitable number of clips  190  or other similar suitable structures may be provided. 
         [0036]      FIGS. 8-10  illustrate stages of connecting the filter head  104  to the filter element  106 . For visualization purposes, the spacers  140  are not shown in these figures. Furthermore, for simplification and explanation, the second end cap  158 /filter head connector  164  is shown as detached from the filter element  106  and the filter head disc member  146  is shown as detached from the filter head  104 . Therefore, it will be appreciated that references made or shown regarding the filter element  106  may apply to the second end cap  158 /filter head connector  164  and vice versa. Similarly, references made or shown regarding the filter head  104  may apply to the filter head disc member  146  and vice versa. 
         [0037]    Turning to  FIG. 8 , in order to couple the filter element  106  to the filter head  104 , the extension members  132  of the filter head  104  are aligned with the guide surfaces  174  of the connector portion  168 . The distal ends of the guide surfaces  174  form the smallest external diameters of the connector portion  168 . Thus, given the positions of the extension members  132  on the filter head  104 , the guide surfaces  174  operate as the only entry points for receiving the extension members  132 . The outer diameter of the remaining distal edges of the connector portion  168  are large enough such that they abut the extension members  132  if the filter head  104  and filter element  106  are moved axially toward one another at positions other than the guide surfaces  174 . It will be appreciated that any suitable number of extension members  132  may be received by any suitable number of guide surfaces  174 . 
         [0038]    As the filter head  104  and the filter element  106  are moved axially toward one another, the shaped ends  138  of the extension members  132  may slide along the guide surface  174 . As shown in  FIG. 9 , the extension members  132  may bend radially outward as they approach the proximal end  170  of the connector portion  168 . The shaped ends  138  may then reach the rest position  186  on the guide surface  174 . The filter element  106  and filter head  104  are prevented from moving any closer to one another by the spacers  140  and/or the extension members  132  contacting the base  166  of the filter head connector  164 . At this position, the filter element  106  and the filter head  104  are still separable by pulling them away from one another. 
         [0039]    The filter element  106  and the filter head  104  may then be rotated relative to one another to securely couple these components to one another. For example, the filter head connector  164  may be rotated clockwise relative to the filter head  104 . In other embodiments, the filter head connector  164  may be rotated counter-clockwise relative to the filter head  104 . When rotating, the lead-in edges  194  of the clips  190  contact the extension members  132 , and the clips  190  may bend outward as appropriate to slide along the outer surface of the extension members  132 . As the filter head connector  164  continues to rotate, the shaped ends  138  of the extension members  132  will slide over the rounded ridges  182  and enter the recessed portions  176  as shown in  FIG. 10 . The extension members  132  having previously been bent by the guide surfaces  174  will at least partially move radially inward back to or near its pre-attachment orientation as it moves into the recessed portion  176 . 
         [0040]    The user may be able to detect that the shaped ends  138  are in the recessed portion because the shaped portions may make a clicking noise, the user will not be able to rotate the filter head connector  164  any further because the shaped ends  138  will be stopped from further rotation by the abutments  180 , and counter-clockwise rotation is resisted by the rounded ridges  182 . Furthermore, as the last portions of the extension members  132  slide past the rounded ridges  182 , a small rotational force may exist to allow the user to feel when the shaped ends  138  have engaged the recessed portions  176 . Requiring the user to rotate the filter element  106  and filter head  104  relative to one another is beneficial because it is intuitive for users to rotate components to engage them. 
         [0041]    When the extension members  132  enter the recessed portions  176 , the lead-in edges  194  of the clips  190  may pass beyond the width of the respective extension members  132  and the backside edges  196  may abut the sides of the extension members  132 . The clips  190 , similar to the extension members  132 , may move radially inward to return at least partially to its pre-contact non-bent orientation. 
         [0042]    The filter element  106  and the filter head  104  are now securely attached to one another. Axial separation of the filter element  106  and the filter head  104  is resisted by the ledges  188  at the intersection of the recessed portions  176  and the locking portions  178 . The ledges  188  may contact the shaped ends  138  of the extension members  132  to act as a stop if axial separation is attempted. The clips  190  add further security to the connection by resisting radial movement of the extension members  132  which would necessarily take place if the extension members  132  were to pass over the locking portions. 
         [0043]    Unintentional disengagement of the extension members  132  and the connector portions  168  is also resisted from rotational movement by the rounded ridges  182  and backside edges  196  of the clips  190 . For example, the rounded ridges  182  resist rotational movement by contacting the shaped ends  138  of the extension members  132 . Further, the backside edges  196  of the clips  190  resist rotational movement by gripping the sides of the extension members  132 . This rotational restriction is sufficient to help resist unintentional disengagement, while permitting intentional disengagement when a user is prepared to separate the filter element  106  from the filter head  104 . 
         [0044]    To disengage the extension members  132  from the connector portion  168 , the connector portion  168  may be rotated counter-clockwise. A force sufficient to slide the shaped ends  138  of the extension members  132  over the rounded ridges is necessary to force the shaped end out of the recessed portion  182 . As the shaped ends  138  pass over the rounded ridges, the edges of the extension members  132  also slide along the angled backside edges of the clips  190  forcing the clips  190  to bend radially outward. The half-arrowhead ends  192  of the clips  190  then slide across the extension members  132  as the connector portion  168  continues to rotate. The shaped ends  138  of the extension members  132  move onto the rests  186  of the guide surfaces  174  until they are stopped by the guide surface abutments  184 . The filter element  106  may then be separated from the filter head  104  by moving these components axially away from one another. The shaped ends  138  will slide along the guide surfaces  174  and return to their original non-bent orientation as the shaped ends  138  separate from the guide surfaces  174  at the distal ends  172  of the connector portion  168 . 
         [0045]    It will be appreciated that the connector  164  may be used with any suitable filter element  106  and/or filter head  104 . It will also be appreciated that the connector portion  168  may alternately be attached to the filter head  104  and the extension members  132  may alternately be attached to the filter element  106 . 
         [0046]    Filter elements and assemblies including removably attachable connector structures for securely coupling a filter element to a filter head have been disclosed herein. 
         [0047]    Any references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein. 
         [0048]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0049]    Preferred embodiments of this invention are described herein, including the best mode known to the inventor(s) for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor(s) expect skilled artisans to employ such variations as appropriate, and the inventor(s) intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.