Abstract:
A “no filter, no run” filtration system that is designed to verify that an appropriate filter cartridge is installed. A flow control valve is provided on a standpipe to control the flow of fuel into the standpipe. The valve has a component that has a first position at which any flow through the flow passage past the valve is insufficient to permit engine operation, and a second position at which a greater amount of flow through the flow passage is permitted by the valve in an amount sufficient to permit engine operation, and the component rotates about the longitudinal axis when it moves from the first position to the second position and from the second position to the first position.

Description:
FIELD 
     This disclosure generally pertains to the field of filtration, and more particularly to fuel filtration systems designed to safe-guard against damage to fuel injectors, associated fuel components, and engine malfunctions resulting from a missing or incorrect fuel filter. 
     BACKGROUND 
     Fuel filtration systems are known that are designed to completely prevent flow of fuel to an engine if no filter cartridge is installed or in the incorrect filter cartridge is installed. In these “no filter, no run” systems, not only must a filter be present, but the correct filter must be used, in order to allow fuel to flow to the engine. 
     SUMMARY 
     A “no filter, no run” filtration system that is designed to verify that a filter cartridge is present to safe-guard against damage to fuel injectors, associated fuel components, etc. and engine malfunctions. Fuel flow to the engine is generally prevented if a filter cartridge is not installed in order to prevent engine operation, and an appropriately designed filter cartridge is required to be used in order to permit sufficient fuel flow for engine operation. 
     A flow control valve is provided on a standpipe to control the flow of fuel into the standpipe. The valve can be axially moveable between closed and open positions, with one or more members on an installed filter cartridge designed to release the valve to permit the movement from the closed position to the open position to allow full fuel flow. A spring biases the valve back to the closed position upon removal of the filter cartridge. 
     In one embodiment, a standpipe includes a valve having a component that has a first position at which flow (if any) through the flow passage past the valve is insufficient to permit engine operation, and a second position at which flow through the flow passage is permitted by the valve in an amount sufficient to permit engine operation, and the component rotates about the longitudinal axis when it moves from the first position to the second position and from the second position to the first position. 
     Rotation of the valve component is caused by the filter cartridge end plate when the filter cartridge is installed. In particular, the end plate includes at least one protrusion extending therefrom into the interior space of the filter at a position offset from the central axis. The protrusion includes an angled actuating edge that is at an acute angle relative to the central axis. The angled actuating edge engages the valve component and causes it to rotate. 
     In another embodiment, the valve is disposed on an exterior of the standpipe outside the internal flow passage, and the valve is moveable between a closed position at which flow (if any) through the flow passage is insufficient to permit engine operation and an open position at which flow through the flow passage permits engine operation. The valve includes a valve stop that is rotatable about the longitudinal axis when the valve moves between the closed and open positions and a valve cap that is engaged with the valve stop. In addition, the valve stop and the valve cap are movable in an axial direction parallel to the longitudinal axis when the valve moves between the closed and open positions. 
     Further, the concepts described herein can be used to ensure that a filter cartridge with the correct micron efficiency rating is used. The same housing may be used for multiple applications, with the housings having slightly different valves. For example, the engagement features between the filter cartridge and the valve can be varied. One possible embodiment is to change the size of the openings in the end cap of the valve and the size of the projections on the filter cartridge that fit through the openings. Only the correct filter cartridge having the correctly sized projections that are able to extend through the openings and cause rotation of the valve can be used. This prevents the customer from mistakenly using the wrong filter if filters of similar size but different media are available. 
     In certain designs, the valve can be designed to prevent all flow. In addition, the valve can allow an amount of fuel to get past the valve and into the standpipe when the valve is closed in an amount sufficient to allow the fuel to lubricate downstream components, for example the fuel pump, yet is insufficient to allow the engine to operate. In some designs, the valve can be manufactured to less exacting tolerances since the valve need not completely shut off fuel flow, thereby reducing the cost of manufacture of the valve. In other designs, the valve and/or standpipe can be manufactured with features to permit a controlled amount of flow past the valve when the valve is closed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a sectional view of a filter housing. 
         FIG. 2  is a detailed view of the end of the standpipe with the valve. 
         FIG. 3  is an exploded view of the valve components. 
         FIG. 4  is a perspective view of the valve cap. 
         FIG. 5  is a perspective view of an embodiment of an end plate on a filter cartridge used to actuate the valve. 
         FIG. 6  is a view of the valve actuated by the filter cartridge end plate. 
         FIG. 7  illustrates a valve that allows a controlled amount of fuel into the standpipe when the valve is closed. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a filter housing  10 , for example a fuel filter housing, which forms part of a filter assembly that is intended to filter a fluid, for example fuel, prior to the fluid reaching an engine. The housing  10  is designed to receive a filter cartridge  12 , illustrated in  FIG. 3 , therein for filtering the fluid. The description will hereinafter refer to the filter housing  10  as being a fuel filter housing, and that the fluid being filtered is fuel, for example diesel fuel. However, in appropriate circumstances, the concepts described herein can be applied to other types of filter assemblies that filter other types of fluids, for example oil. 
     The filter housing  10  includes a housing body that has a side wall  16  and an end wall  18 . The side wall  16  and the end wall  18  define a filter cartridge space  20  that is large enough to receive the filter cartridge  12  therein, with the end wall  18  forming a closed end of the space  20 . The housing body has an open end  22  generally opposite the end wall  18 , with the open end  22  in use being closed by a cap (not shown) that closes off the space  20 . The housing body also includes an inlet opening (not shown), which can extend, for example, through the side wall  16 , and through which fuel to be filtered enters the housing  10 , and an outlet  26 , illustrated as extending from the end wall  18 , through which fuel exits on its way to the engine. It is to be realized that the filter housing  10  could have other configurations than that described herein. 
     A standpipe  30  is secured to the end wall  18  and extends upwardly into the space  20  toward the open end  22 . In the illustrated embodiment, the standpipe  30  is generally hollow from its end  32  connected to the end wall  18  to a tip end  34  thereof, thereby defining an internal flow passage  36 , best seen in  FIG. 3 . The flow passage  36  is in communication with the outlet  26  so that fuel that enters the standpipe  30  can flow from the standpipe and into the outlet  26  to the engine. The standpipe  30  is disposed generally centrally in the housing  10 , with a central axis A-A of the standpipe  30  generally coaxial with a central axis of the space  20 . 
     In the embodiment illustrated in  FIG. 1 , the standpipe  30  is generally cylindrical and the passage  36  is generally circular along its length when the standpipe  30  is viewed in a cross-section taken perpendicular to the central axis A-A. However, the standpipe  30  and the passage  36  could have other configurations, such as non-cylindrical and non-circular. For example, the passage  36  could be oval in cross-section. In addition, the standpipe  30 , the end  32 , the tip end  34 , the outlet  26 , and the passage  36  can be of unitary construction or comprised of multiple parts. 
     The standpipe  30  includes a section  40   a  with a generally constant diameter and a section  40   b  that includes the tip end  34  having a smaller diameter than the section  40   a . A shoulder  42  is defined at the juncture of the sections  40   a ,  40   b  resulting from the decrease in diameter. One or more openings  44  are formed in the section  40   a  of the standpipe  30  near the shoulder  42  to place the exterior of the standpipe in communication with the passage  36 . In the illustrated embodiment, one opening  44  is present. However, a larger number of openings  44  can be provided. 
     A flow control valve  50  is disposed on the standpipe  30  adjacent the tip end  34  to control the flow of fuel into the standpipe through the opening  44 . The valve  50  is axially moveable between closed ( FIG. 2 ) and open positions, with one or more members on the installed filter cartridge  12  designed to release the valve to permit the movement from the closed position to the open position. A spring  52  biases the valve back to the closed position upon removal of the filter cartridge  12 . 
     With reference to  FIGS. 1-4 , the valve  50  comprises a valve cap  54  having a skirt or sleeve section  56  and a top plate  58 , a valve stop  60 , and the spring  52  for biasing the valve cap  54  and valve stop  60  to the closed position shown in  FIG. 2 . The valve cap  54 , valve stop  60  and spring  52  are made of materials, the same or different, suitable for exposure to fuel or other type of fluid flowing through the housing  10 . For example, these elements can be made of plastic or metal. 
     As seen in  FIGS. 1 and 2 , the valve cap  54  covers the tip end  34 . The skirt section  56  of the valve cap  54  extends downward and covers approximately half of the section  40   a . The skirt section  56  is substantially solid, except for one or more openings  62  extending through the skirt section  56 . The opening  62  is located on the skirt section  56  above the location of the opening  44  in the standpipe such that at the closed position shown in  FIGS. 1 and 2 , the skirt section  56  generally prevents the flow of fuel into the standpipe opening  44 . The opening  62  is spaced from the opening  44  such that when the valve cap  54  moves axially downward to an open position, the opening  62  is generally aligned with the opening  44  to allow fuel to flow into the standpipe opening  44 . In the illustrated embodiment, one opening  62  is shown, although a larger number of openings can be provided. 
     The top plate  58  of the valve cap  54  generally closes the upper end of the skirt section  56 . With reference to  FIG. 4 , the top plate  58  includes a plurality of circumferentially spaced, axially extending openings  64   a - d  formed therethrough that provide access to the interior of the valve cap  54  through the top plate  58 . Between the openings  64   a - d  are bridges  66   a - d  that connect a solid, central portion  68  of the top plate with the skirt portion  56 . Each bridge  66   a - d  includes sloped surfaces  68   a, b  that meet at a common edge  70 . The sloped surfaces  68   a, b  help guide protrusions (described below) provided on the filter cartridge  12  into the openings  64   a - d  of the valve cap  54  during actuation of the valve  50 . 
     A plurality of valve cap protrusions  72   a - d  are integral with and extend downwardly from the bridges  66   a - d . The protrusions  72   a - d  are spaced from the interior wall of the skirt section  56  and, as shown in  FIG. 3 , each protrusion includes a sloped edge  74  that is disposed at an acute angle to the axis A-A and to a horizontal axis that is perpendicular to the axis A-A, and an edge  76 . The purpose of the edges  74 ,  76  will be described below. 
     The valve stop  60  is also disposed on the tip end  34 , within the valve cap  54 . The valve stop controls axial movement of the valve cap  54  from the closed to the open positions. The tip end  34  of the standpipe  30  is uniquely designed to receive the valve stop  60 . In particular, with reference to  FIG. 2 , the tip end  34  includes four recessed areas  80  thereon that are circumferentially spaced around the diameter of the tip end  34 . Each recessed area  80  includes a first component  82  and a second component  84 , and each recessed area  80  is bordered by a surface  86 , a surface  88 , a surface  90 , and a surface  92 . In the illustrated embodiment, the surfaces  86 ,  90  and  92  are generally parallel to the axis A-A, while the surface  88  is generally perpendicular to the axis A-A. However, the surfaces  86 ,  90 ,  92  need not be generally parallel to the axis A-A, but can be at any angle(s) that are compatible with any mating component surfaces of the valve. Further, the surface  88  need not be generally perpendicular to the axis A-A, but the surface  88  can be at any angle that will mate with the valve properly. 
     Returning to the valve stop  60  and  FIGS. 1-3 , the stop  60  comprises a support plate  100 . Extending downwardly from the plate  100  are a plurality (in the illustrated embodiment, four) of circumferentially spaced legs  102  that are designed to fit in the recessed areas  80 . As best seen in  FIG. 2 , each leg  102  includes a major portion  104 , and a finger  106  that projects downwardly from the end of the major portion  104  at one edge of the major portion  104 . The width of the major portion  104  is slightly less than the distance between the surfaces  90 ,  92 . As shown in  FIG. 2 , at the closed position of the valve  50 , the end of the major portion  104  next to the finger  106  will engage the surface  88  and prevent downward movement of the stop  60 . The stop  60  must be rotated to the position shown in  FIG. 6  so that the major portion  104  clears the surface  88 , which will allow the stop  60  to move axially downward until the end of the finger  106  engages the shoulder  42  or the plate  100  engages the end of the tip end  34 . In an alternative embodiment, the legs  102  and fingers  106  could be designed to fit on the inside of the tip end  34  of the standpipe  30 . 
     Extending upwardly from the plate  100  are a plurality (in the illustrated embodiment, four) of circumferentially spaced protrusions  110 . Each protrusion  110  includes sloped edges  112 ,  114  that join at edge  116 . In the illustrated embodiment, the edges  112 ,  114  slope at approximately the same angle a ( FIG. 6 ) relative to a vertical axis. The protrusions  110  are designed to be engaged by protrusions on the filter cartridge  12 , and when so engaged, cause rotation of the stop  60  in the direction of the arrow in  FIG. 2  to the position shown in  FIG. 6 . If desired, the components can be modified so that the stop rotates in the direction opposite to that indicated in  FIG. 2 . 
     Upon rotation of the stop  60  to the position shown in  FIG. 6 , the legs  102  clear the surface  88 , allowing the stop  60  to drop down axially. Since the valve cap  54  rests on the stop  60 , the cap  54  drops down with the stop  60  to align the openings  44 ,  62 . 
     The spring  52  surrounds the tip end  34  and is engaged between the shoulder  42  and the plate  100  on the stop  60 . When the stop  60  and cap  54  move downward, the spring  52  is compressed. As a result, when the filter cartridge  12  is removed, the spring  52  biases the stop  60  and the cap  54  upward. 
     Rotation of the stop  60  and resulting axial movement of the stop and valve cap  54  occurs as a result of installing the correct filter cartridge  12 . Returning to  FIG. 3 , the cartridge  12  is illustrated schematically in cross-section. The cartridge  12  includes a ring of filter media  150  suitable for filtering fuel. The outside of the filter media  150  defines a dirty or unfiltered fuel side while inside the ring of media  150  is a clean or filtered fuel side. Thus, the filter cartridge is configured for outside-in flow. 
     A first end cap or plate  152  is secured to the bottom end of the media  150  for generally closing the bottom end of the media. The plate  152  includes an opening  154  therethrough through which the standpipe  30  is inserted upon installation of the filter cartridge  12 . A seal (not shown) will typically be provided on the plate  152  to seal with the standpipe  30  to prevent leakage of clean fuel past the plate  152 . Alternatively, a seal can be provided between the plate  152  and the bottom of the housing. A second end cap or plate  156  is secured to the opposite end of the media  150  for closing off the opposite end of the media. 
     With reference to  FIGS. 3 and 5 , the plate  156  is illustrated as being generally flat and planar. However, the plate  156  includes a plurality of projections  160 , for example four, that project generally parallel to the axis A-A downwardly into the interior space of the media  150  from the bottom surface of the plate  156 . The projections  160  are illustrated as being circumferentially spaced from each other, and spaced from the center of the plate  156 . 
     The projections  160  are positioned and shaped to extend through the axial openings  64   a - d  in the top plate  58  of the valve cap  54 , and to engage with the protrusions  110  on the valve stop  60  in order to rotate the valve stop. Any configuration of the projections  160  capable of engaging with the protrusions  110  to cause rotation of the valve stop  60  can be used. As illustrated, each projection  160  includes a first axial edge  162  extending generally parallel to the axis A-A, a second axial edge  164 , and a sloped actuating edge  166  that extends at an acute angle to the axis A-A. 
     Upon installation of the filter cartridge  12 , the projections  160  enter into the valve cap  54  through the openings  64   a - d . The sloped surfaces  68   a , b on the bridges  66   a - d  help guide the projections into the openings when installing the cartridge  12 . During installation, the sloped actuating edges  166  engage the sloped edges  114  on the protrusions  110 . The engagement between the edges  114 ,  166  creates a sideways force that causes the valve stop  60  to rotate to the position shown in  FIG. 6 . The stop  60  and the valve cap  54 , together with the filter cartridge  12 , can then move down axially to align the openings  44 ,  62 . 
     Upon removal of the filter cartridge  12 , the spring  52  will bias the valve stop  60  upward. Simultaneously, the sloped edges  112  on the protrusions  110  will engage the sloped edges  74  on the protrusions  72   a - d  of the valve cap  54 , which causes the valve stop  60  to rotate back to its position shown in  FIG. 2 , i.e. the closed position. The edges  76  limit rotation of the valve cap  54  by engaging with the protrusions  110 . If a standard filter cartridge without suitable protrusions is installed, the valve stop and valve cap  54  will not slide down the standpipe, and the filter cartridge will project upward from the housing  10  and prevent installation of the housing cover. This will act as a sign that the incorrect filter cartridge has been installed. 
     The valve described herein can permit a certain amount of fuel flow into the standpipe when the valve is at the closed position. The amount of fuel allowed past the valve should be insufficient to permit engine operation, and in certain embodiments can be insufficient to lubricate downstream components, for example the fuel pump in the case of diesel fuel. In another embodiment, the amount of fuel permitted past the valve when closed can be sufficient to provide lubrication to downstream components, for example the fuel pump, in the case of diesel fuel, yet be insufficient to permit engine operation. Since fuel flow need not be completely prevented, the valve components described herein can be manufactured to less exacting tolerances. This permits reduction in the cost of manufacture of the valve components, especially the valve cap, since they need not fit closely with the standpipe. If fuel flow must be prevented entirely, the components can be manufactured to more exacting tolerances and/or suitable sealing can be provided. 
     An example of fuel flowing past the valve when closed is illustrated schematically in  FIG. 7 . A standpipe  200  has a valve  202  around it which controls flow into a standpipe opening  204 . The valve  202  can be configured similarly to the valve  50 , or the valve  202  can just be a sleeve. The valve  202  is designed to be axially moveable on the standpipe  200  between a closed position shown in  FIG. 7  and an open position. When the valve  202  is at the closed position in  FIG. 7 , a controlled amount of fuel can flow into the standpipe through space between the valve  202  and the outside of the standpipe  200  as shown by the arrows. The fuel entering the standpipe, if sufficient, can provide lubrication to downstream components, for example the fuel pump. However, the amount of fuel entering the standpipe is insufficient to permit engine operation. In this embodiment, the tolerances between the outer surface of the standpipe  200  and the inner surface of the valve  202  need not be precise and the valve need not closely fit on the standpipe. As a result, the valve can be manufactured at less cost. 
     In other designs, the valve cap and/or standpipe can be manufactured with features to permit fuel to pass when the valve is closed. For example, grooves or channels could be provided on the valve cap and/or the standpipe to permit fuel past the valve when the valve is at the closed position. 
     Therefore, the word prevention as used herein in the summary, detailed description, and claims, unless indicated otherwise, is meant to include complete shut off of fuel into the standpipe as well as including some passage of fuel into the standpipe, as long as the amount of fuel that passes is insufficient to permit engine operation. 
     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.