Abstract:
A cartridge top load filter design and filter element useable with the filter are described that allows fluid to be drained from the filter housing, from the exterior of the housing and without first removing the filter element or the housing cover. The draining feature can be manually activated by a knob that is accessible from the exterior of the filter housing adjacent to the removable cover. The draining feature does not require any tools to activate, and provides a “clean service” option of draining fluid before opening the filter housing.

Description:
FIELD 
       [0001]    A cartridge top load fluid filter housing that is provided with the ability to drain the fluid filled chamber of the housing prior to filter element servicing, from outside the housing and without removing the housing cover. 
       BACKGROUND 
       [0002]    Current spin-on filter designs typically have no convenient way of draining the filter for service. A common practice is to punch a hole in the bottom of the spin-on filter housing with a sharp object to allow the fluid to be drained out. Some fluid filter modules do have the ability to drain the filter housing, but only when the filter element or the cover are removed. In addition, some fuel modules have drain valves that are very difficult to access due to engine components in close proximity to module. 
       SUMARY 
       [0003]    A cartridge top load fluid filter design is described that allows fluid to be drained from the filter housing, from the exterior of the housing and without first removing the filter element or the housing cover. In the described examples, the draining feature is manually activated by a knob that is accessible from the exterior of the filter housing adjacent to the removable cover. However, the draining feature could be manually activated using other mechanisms accessible from other locations on the exterior of the housing. Regardless of how manual activation occurs, the draining feature does not require any tools (although a tool may be used to help manually activate the knob). In the case of oil as the fluid, the draining feature provides a “clean service” option of draining oil back to the engine block or to a collection pan before opening the filter housing. 
         [0004]    In one embodiment, a method of draining fluid from a cartridge top load fluid filter housing is described. The filter housing has a cover removably attached to a housing base with a filter element installed within the housing, and a drain port adjacent to a bottom of the housing base. The method includes, with the cover attached to the housing base, displacing the filter element from a first position to a second position within the filter housing. At the first position, fluid is prevented from flowing through the drain port and at the second position fluid is permitted to flow through the drain port. The displacement of the filter element from the first position to the second position occurs from outside of the filter housing without removing the cover. 
         [0005]    In the described examples, the displacement of the filter element occurs from the top of the housing. In the described examples, the displacement is accomplished by incorporating an actuation knob accessible from outside the filter housing that when manually actuated creates upward axial displacement of the filter element from the first position to the second position to open a drain port that drains the filter housing, without opening the cover. After the housing is drained, the cover can be removed and the filter element extracted from the housing with minimal fluid spillage and less mess than would be otherwise possible. 
         [0006]    The method of draining fluid described herein is unique, as is the filter housing construction and the filter element construction. 
         [0007]    The filter element can include a ring of filtration media having a first end and a second end and circumscribing a central cavity having a longitudinal axis. A first endplate is sealingly attached to the first end of the filtration media, and a second endplate is sealingly attached to the second end of the filtration media. The second endplate has a standpipe opening through which a standpipe can extend and a gasket disposed in the standpipe opening for sealing engagement with a standpipe extending through the standpipe opening. The second endplate can also have a perimeter edge, and a sleeve extending from the second endplate in a direction away from the first endplate parallel to the longitudinal axis. The sleeve has a diameter greater than a diameter of the standpipe opening so that the sleeve surrounds the standpipe opening. The sleeve has one end connected to the second endplate at a location between the standpipe opening and the perimeter edge and an opposite end spaced from the one end. A radial outward facing seal is disposed adjacent to the opposite end of the sleeve so that the radial outward facing seal is disposed at a radial position between the longitudinal axis and the perimeter edge. 
         [0008]    A top load cartridge design with filter element drain actuation features (e.g. a knob or a cap) integrated into the lid is also described. 
         [0009]    The lower end of the drain actuation knob seals (for example, radially as illustrated or optionally axially via a face seal) with the filter element endplate to prevent flow bypass and interfacing/mating with an extension on the standpipe or the center tube to provide lateral support to the filter element to center the filter element and provide strength to withstand radial vibration forces. 
         [0010]    The lower end of the drain actuation knob interfaces with an extension on the standpipe to prevent an incorrect filter element from being installed (e.g. a filter element without the central hole in the endplate and/or sealing engagement surface to mate with the valve). 
         [0011]    Optionally, a reverse configuration can also be used whereby a post-like or cylinder-like extension on the knob can engage with the center tube or the standpipe to provide similar lateral support, centering, strength to withstand radial vibration forces, and incorrect filter installation functions. 
         [0012]    It is contemplated that the draining and filter concepts described herein could be used in a number of applications including, but not limited to, oil, fuel, or other liquid applications where drainage of a housing prior to service is desired. 
     
    
     
       DRAWINGS 
         [0013]      FIG. 1  illustrates a first embodiment of a filter housing with an installed filter element at the first or closed position. 
           [0014]      FIG. 2  illustrates the filter housing of  FIG. 1  with the filter element displaced to the second or open position allowing draining of fluid. 
           [0015]      FIG. 3  illustrates the filter housing of  FIG. 1  with the filter element and the cover removed from the filter housing. 
           [0016]      FIG. 4  is a cross-sectional view of the filter element of  FIG. 1 . 
           [0017]      FIG. 5  is a cross-sectional view of the cover of  FIG. 1 . 
           [0018]      FIG. 6  is a perspective view of the standpipe used in the filter housing of  FIG. 1 . 
           [0019]      FIG. 7  illustrates a second embodiment of a filter housing with an installed filter element at the second or open position. 
           [0020]      FIG. 8  illustrates the filter housing of  FIG. 7  with the filter element and the cover removed from the filter housing. 
           [0021]      FIG. 9  is a cross-sectional view of the filter element of  FIG. 7 . 
           [0022]      FIG. 10  is a cross-sectional view of the cover of  FIG. 7 . 
           [0023]      FIG. 11  is a perspective view of the standpipe used in the filter housing of  FIG. 7 . 
           [0024]      FIG. 12  is a side view of a valve shaft used in the cover of  FIG. 10 . 
           [0025]      FIG. 13  is a detailed cross-sectional view of the first or upper endplate of the filter element of  FIG. 9 . 
           [0026]      FIG. 14  illustrates another embodiment of a filter housing with an installed filter element at the first or closed position. 
       
    
    
     DETAILED DESCRIPTION 
       [0027]    The described embodiments describe a fluid filter that allows fluid in the filter housing to be drained from the filter housing, from the exterior of the housing and without first removing the filter element or the housing cover. In the described examples, a simple hand-operated knob is used to open the fluid drain port, with no special tool requirements. The lower portion of knob applies axial pressure on the filter element which keeps the filter element at a first position to close the drain port during normal operation. Actuation of the knob permits the filter element to displace to a second position to open the drain port and allow the fluid to drain. The knob is sealed by means of a face seal at the knob/cover interface and the drain port is sealed by a radial seal between a lower endplate of the filter element and the filter housing. 
         [0028]    The concepts described herein could be used in a number of applications including, but not limited to, oil, fuel, or other engine fluids, or other liquid applications where drainage of a housing prior to service (for example, replacement of the filter element) is desired. One particular exemplary application illustrated in the drawings is for an oil filter and draining oil from the filter housing back to the oil pan. However, unless the particular fluid or application is specifically identified, it is contemplated that the concepts described herein could apply to fluids and applications other than oil. 
         [0029]    The filter element is an integral link between the knob and the drain port. In the described examples, an extension to the standpipe post interfaces with the knob and is used for alignment and structural support, and which also prevents an incorrect filter element (i.e. an element without the central hole on the top endplate which interfaces with the knob) from being misapplied to the filter housing. Alternatively, an extension projecting downward from the knob could interface with the top of the standpipe or center tube. 
         [0030]    In the example illustrated in  FIGS. 1-6 , the knob is turned counterclockwise which allows the spring to displace the filter element upward to open the drain port. 
         [0031]    In the example illustrated in  FIGS. 7-13 , a retention feature is incorporated on the lower component of the knob assembly that engages the filter element top endplate, pulling the filter element up without spring assistance. 
         [0032]    In the example illustrated in  FIG. 14 , a protrusion on the filter element upper endplate engages with the cover. The filter element is forced downward against spring pressure during normal operation. To drain, the operator removes a simple threaded (or ¼-turn) cap which vents the system and allows the protrusion and the filter element to displace upward, opening the lower drain port. After replacing the filter element, the cap could be reinstalled either before or after reinstalling the cover. The pocket created in the cap could also be used to hold a slow-release fluid additive. 
         [0033]    Each of the examples in  FIGS. 1-14  can utilize an “extension” to the standpipe (or center tube) which engages with the inner diameter of the knob assembly projecting through the filter element endplate to provide an alignment feature for the filter element, and to provide structural support for resisting radial vibration forces. 
         [0034]    In the example illustrated in  FIGS. 7-13 , the filter element would be extracted with the cover when the cover is removed after draining The filter element could then be disengaged from the retention feature on the cover via radial force on the bottom of filter element relative to the cover. Optionally, the filter element could be disengaged from the cover by the user further rotating (for example counterclockwise) the knob, causing the inner element to “stop out” against the cover, after which any additional rotation of the knob would cause detachment of the snap feature, freeing the filter element from the cover, and assisting with the clean-service experience (i.e. no touch of the filter element). 
       FIGS. 1-6 
       [0035]    With reference to  FIGS. 1-6 , a cartridge top load filter  10  is illustrated. The filter  10  includes a cartridge top load filter housing  12  composed of a housing base  14  and a cover  16  removably attached to the housing base, for example using threads  18 . During normal use, a filter element  20  is installed within the housing. 
         [0036]    With reference to  FIGS. 1-3 , the housing base  14  includes a standpipe  22 , a fluid inlet  24  through which fluid enters the housing  12  to be filtered, a clean fluid outlet  26  through which filtered fluid exits the filter  10 , and a drain port  28  adjacent to a bottom of the housing base  14 . A coil spring  30  is disposed around the standpipe  22  which in use applies an upward biasing force on the filter element  20  to bias the filter element in a direction toward the second or open position shown in  FIG. 2 . 
         [0037]    With reference to  FIGS. 3 and 4 , the filter element  20  includes a ring of filtration media  40  having a first end  42  and a second end  44  and circumscribing a central cavity  46  having a longitudinal axis A-A. A first endplate  48  is sealingly attached to the first end of the filtration media, and a second endplate  50  is sealingly attached to the second end of the filtration media. 
         [0038]    The second endplate  50  includes a standpipe opening  52  through which the standpipe  22  can extend and a gasket  54  disposed in the standpipe opening  52  for sealing engagement with the standpipe extending through the standpipe opening. The endplate  50  also includes a perimeter edge  56 , and a sleeve  58  extending from the second endplate in a direction away from the first endplate parallel to the longitudinal axis A-A. The sleeve  58  has a diameter greater than the diameter of the standpipe opening  52  so that the sleeve  58  surrounds the standpipe opening. The sleeve has a first end end  60  connected to the second endplate at a location between the standpipe opening and the perimeter edge and an opposite or second end  62  spaced from the first end  60 . A radial outward facing seal  64 , for example an o-ring seal, is disposed adjacent to the second end  62  of the sleeve. The radial outward facing seal  64  is disposed at a radial position between the longitudinal axis A-A and the perimeter edge  56 . 
         [0039]    The first endplate  48  includes an opening  66  therethrough defined by a sleeve  68  that extends from the first endplate into the central cavity  46  in a direction toward the second endplate. The opening  66  in the first endplate is aligned with the standpipe opening  52  in the second endplate. 
         [0040]    The filter element  20  further includes a perforated center tube  70  that extends between and is fixed at each end thereof to the endplates  48 ,  50 . 
         [0041]    With reference to  FIGS. 2 ,  3  and  5 , the cover  16  includes a knob  80  that is fixed to a valve shaft  82  that extends through the cover. The knob  80  includes a flange  84  that, in the closed position, seals with a knob seal  86  located in a recessed flange receiving area  88  in the cover  16 . The outer diameter of the valve shaft  82  includes threads  90  that engage with threads  92  formed on the cover passageway through which the valve shaft extends. As the valve shaft  82  is rotated by turning the knob  80  in one direction (for example counterclockwise), the valve shaft  82  is caused to displace in a direction upward out of the cover. Conversely, as the valve shaft is rotated by turning the knob in the other direction (for example, clockwise), the valve shaft  82  is caused to displace in a direction inward into the cover. Preferably, the knob  80  and valve shaft  82  assembly are fixed together to form a single structure, and they cannot be readily removed from the cover  16 . 
         [0042]    The valve shaft  82  also includes a radial valve shaft seal  94  that engages and seals with a radial sealing surface  96  on the sleeve  68  of the endplate  48  as shown in  FIG. 2 . The seal  94  prevents fluid flow between the filter element  20  and the valve shaft  82 . The valve shaft  82  also includes a vent feature as discussed further below with respect to  FIGS. 7-13 . 
         [0043]    With reference to  FIGS. 2-3  and  6 , the standpipe  22  is generally hollow and includes one or more fluid openings  100  therein through which fluid that has been filtered by the filter element  20  flows to reach the clean fluid outlet  26 . The upper end of the standpipe is provided with an alignment feature  102  that is configured to interface/mate with the lower end of the valve shaft  82  to provide lateral support to the filter element  20 , to help center the filter element, and provide strength to withstand radial vibration forces. 
         [0044]    In the illustrated example, the alignment feature  102  comprises a fluted post that extends upwardly from the top end of the standpipe  22 . The fluted post has a primary outer diameter section  105  along the majority of its length, and then tapers in diameter near its tip end  104 . The tapered tip end  104  helps guide the filter element into correct position during installation into the filter housing. With reference to  FIG. 1 , when the filter element is at its first position, the tip end  104  fits into a correspondingly shaped hole  106  formed in the valve shaft  82  while a portion of the primary outer diameter section  105  of the fluted post fits within a lower section  107  of the valve shaft  82 . With reference to  FIG. 2 , when the filter element displaces to its second position, the fluted post is still disposed within the lower section  107  of the valve shaft to help stabilize the filter element during draining 
         [0045]    The operation of the filter  10  is as follows. During use, the filter  10  is arranged as illustrated in  FIG. 1 . In this configuration, which can be termed the closed configuration of the filter, the filter element  20  is in its first or closed position at which the seal  64  on the sleeve  58  seals with a sealing surface  108  on the housing base  14 . This prevents fluid from reaching the drain port  28 . Instead, all fluid to be filtered that enters the filter housing flows radially inward through the filter media  40  into the central cavity  46 , into the opening(s)  100  in the standpipe, and then out through the clean fluid outlet  26  as shown by the arrows in  FIG. 1 . 
         [0046]    When the filter  10  is to be serviced, for example replacement of the filter element  20 , the fluid within the filter housing is first drained prior to opening the filter housing by removing the cover  16 . Draining is achieved by rotating the knob  80  in the appropriate direction, for example counterclockwise. This causes the valve shaft  82  to axially displace upward in the direction of the longitudinal axis. As this occurs, the spring  30  biases the filter element  20  axially upward to axially displace the filter element to its second or open position shown in  FIG. 2 . At this position, the seal  64  no longer seals with the sealing surface  108 . This allows fluid within the housing to flow past the endplate  50 , as shown by the arrows, and out the drain port  28  which can be fluidly connected to a sump or other fluid collection location. 
         [0047]    Once the fluid has been drained, the cover  16  can be removed from the housing base  14 , and the old filter element replaced with a new filter element. The cover  16  is then reattached to the housing base. The knob  80  can be rotated clockwise to return it and the valve shaft  82  to their original position shown in  FIG. 1  before reattaching the cover  16  or after the cover has been reattached to the housing base. 
       FIGS. 7-13 
       [0048]    With reference to  FIGS. 7-13 , a second embodiment of a cartridge top load filter  200  is illustrated. The filter  200  has many similarities to the filter  10 , but eliminates the biasing spring  30  used in the filter  10  and instead employs a snap fit connection design between the valve shaft and the upper endplate of the filter element which causes the filter element to displace axially with the valve shaft when the knob is rotated. The construction and operation of the filter  200  is otherwise identical to the filter  10 . 
         [0049]    In  FIGS. 7-13 , elements identical to elements in the filter  10  will be referenced using the same reference numerals. However, only those features that are different will be described in detail. 
         [0050]    With reference to  FIGS. 7-9  and  13 , the filter element  202  of the filter  200  includes a first endplate  204  that includes an opening  206  therethrough defined by a sleeve  208  that extends from the first endplate into the central cavity in a direction toward the second endplate  50 . The opening  206  in the first endplate is aligned with the standpipe opening  52  in the second endplate. 
         [0051]    The end of the sleeve  208  includes a plurality of circumferentially spaced, inwardly angled snap fingers  210  each of which has an angled ramp surface  212 . 
         [0052]    With reference to  FIGS. 7-8 ,  10  and  12 , the knob  80  is fixed to a valve shaft  214 . The valve shaft  214  includes threads  216  that engage with the threads  92  on the cover passageway through which the valve shaft extends. The threads  216  are interrupted to form at least one channel  218  which allows venting of air during draining which aids in draining A similar vent feature is used in  FIGS. 1-6  described above and in  FIG. 14  described below. 
         [0053]    In addition, the end of the shaft  214  is formed with an enlarged diameter end  220  having a first ramp surface  222  and a second ramp surface  224 . In use, the valve shaft  214  snap fit engages with the endplate  204 . To attach, the end of the valve shaft  214  is inserted into the opening  206 . As this occurs, the first ramp surface  222  engages the snap fingers  210  which forces the fingers outwardly to allow the enlarged diameter end  220  to pass the fingers  210 . Once past the fingers, the fingers  210  snap fit behind the end  220  on the second ramp surface  224 . 
         [0054]    The operation of the filter  200  is generally similar to the filter  10 . During use, the filter  200  would be arranged similarly to that illustrated in  FIG. 1  with the filter element  202  located at its first or closed position (not shown) with the seal  64  sealed with the sealing surface  108 . This prevents fluid from reaching the drain port  28 . Instead, all fluid to be filtered that enters the filter housing flows radially inward through the filter media  40  into the central cavity  46 , into the opening(s)  100  in the standpipe, and then out through the clean fluid outlet  26 . 
         [0055]    When the filter  200  is to be serviced, for example replacement of the filter element  202 , the fluid within the filter housing is first drained prior to opening the filter housing by removing the cover  16 . Draining is achieved by rotating the knob  80  in the appropriate direction, for example counterclockwise. This causes the valve shaft  214  to axially displace upward in the direction of the longitudinal axis. Since the valve shaft  214  is snap fit connected to the filter element, the filter element  202  displaces axially upward with the valve shaft to its second or open position shown in  FIG. 7 . At this position, the seal  64  no longer seals with the sealing surface  108 . This allows fluid within the housing to flow past the endplate  50 , as shown by the arrows in  FIG. 7 , and out the drain port  28  which can be fluidly connected to a sump or other fluid collection location. 
         [0056]    At the second or open position, the endplate  204  is close to or is in contact with the cover  16 . Continued rotation of the knob  80  in the counterclockwise direction continues to force the filter element upward against the cover. As this occurs the angled ramp surfaces  212  ride along the second ramp surface  224  to deflect the snap fingers  210  radially outward to release the snap connection to disconnect the filter element from the valve shaft. This disconnection of the filter element from the valve shaft can occur with the cover  16  attached to the housing base  14 . Alternatively, the cover can be removed from the housing base together with the knob assembly and the filter element. The knob can then be rotated as described above to detach the filter element from the valve shaft. This allows the servicing to be performed clean without the service technician touching the wet filter element. 
         [0057]    A new filter element can then be installed. The new filter element can be attached to the valve shaft prior to re-attaching the cover, or the new filter element can first be installed in the housing base and then the cover re-attached, with the valve shaft being attached to the filter element during re-attachment of the cover. 
       FIG. 14 
       [0058]    With reference to  FIG. 14 , another embodiment of a cartridge top load filter  300  is illustrated. The filter  300  has many similarities to the filter  10 , but eliminates the knob and valve shaft used in the filter  10 . Instead, the filter  300  employs a protrusion  302  on the filter element  304  upper endplate  306  that engages with a cap (or knob)  308  rotatably attached to the cover  310 . The construction and operation of the filter  300  is otherwise identical to the filter  10 . In  FIG. 14 , elements identical to elements in the filter  10  will be referenced using the same reference numerals. However, only those features that are different will be described in detail. 
         [0059]    The protrusion  302  extends upwardly in a direction away from the endplate  50  parallel to the longitudinal axis A-A and into a neck region  312  formed on the cover  310 . The endplate  306  is solid and does not permit fluid flow therethrough. The outer perimeter of the neck region  312  is formed with exterior threads  314  which engage with interior threads  316  formed on the cap  308 . The cap  308  includes a protrusion  322  that extends downwardly from a central portion thereof and into engagement with the top end of the protrusion  302  as shown in  FIG. 14 . 
         [0060]    As illustrated in  FIG. 14 , the cap  308  is fully threaded onto the cover  310 , which forces the filter element  304  downward against the pressure of the spring (not shown) during normal operation where the seal  64  seals with the sealing surface  108  to prevent draining of fluid. To drain, the servicing technician unscrews the cap  308 , which permits the filter element to displace axially upward due to the biasing force of the spring to unseat the seal  64  from the sealing surface  108 . Fluid can then flow past the endplate  50  and to the drain port (not illustrated). 
         [0061]    The cap  308  can be a ¼ turn cap that remains attached to the neck region  312  of the cover and requiring only roughly a ¼ or ½ turn to provide enough displacement of the filter element to allow draining Alternatively, the cap  308  can be completely removable from the neck region. In either case, a tether  320  can be used to tether the cap  308  to the cover  310 . 
         [0062]    After replacing the filter element  304 , the cap  308  could be reinstalled either before or after reinstalling the cover  310 . The pocket created in the cap could also be used to hold a slow-release fluid additive container. 
         [0063]    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.