Abstract:
A capless fuel filler system has lower and upper sealing doors. The upper sealing door prevents water, water vapor, dust, etc. from entering into the space between the lower and upper doors. In prior systems with one sealing door a drain is provided to remove water (either directly entering or condensed water vapor), dust, or excess fuel drips from fueling just upstream of the lower door. By providing two sealing doors, water and dust cannot access the lower door. Although some fuel may puddle upstream of the lower door after a fueling event, the fuel is trapped, with no drain to the exterior, between lower and upper doors. If such fuel evaporates, it causes the lower door to open and vents the fuel vapors to the fuel tank, a desirable disposition for the vapors. The two sealing doors are contained in separate components to facilitate interchangeability and serviceability.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present development relates to a fuel filler assembly for an automotive vehicle. 
         [0003]    2. Background Art 
         [0004]    Capless fuel filler systems are known to provide a sealing door through which a fuel supply nozzle can be inserted for fueling purposes. The upstream side of the sealing door is subjected to ambient conditions. Water may splash up from the vehicle and collect at the upstream side of the sealing door. Also, water vapor may condense and collect near the sealing door. To prevent the collection of water and then entry of the water into the fuel tank during subsequent fueling, a drain is provided to drain away the fluid to a benign location. 
         [0005]    It is also known that when fueling a vehicle some fuel drips off of the fuel filler nozzle when withdrawing the nozzle from the fuel filler system. In the prior art, this fuel collected on the upstream side of the sealing door is also drained away with the same drain. 
         [0006]    It is desirable to eliminate the drain system from the fuel filler system for weight, cost, and complexity reasons. Furthermore, it is desirable to avoid draining away fuel drips, even though the quantity is a small fraction of the fuel delivered during fueling. 
         [0007]    Another issue related to fuel filler pipes is to prevent misfueling. Fuel filler pipes on automotive vehicles are provided with an opening into which a fuel supply nozzle is inserted during refueling. Fuel filler pipes are sized to coordinate with the fuel supply nozzle. It is known, for example, that a diesel fuel supply nozzle is greater in diameter than a gasoline fuel supply nozzle. To prevent misfueling of, for example, a gasoline-fueled vehicle, the vehicle&#39;s fuel filler neck is smaller than the diesel fuel supply nozzle, thereby preventing putting diesel fuel in a gasoline tank. However, the reverse is not prevented by this measure alone. 
         [0008]    There are no international standards on fuel supply nozzles. Thus, even within certain countries, the fuel supply nozzle diameter used for a particular kind of fuel varies from region to region. On a global basis, fuel supply nozzle diameter depends on both the type of fuel being dispensed and the geographic region, thereby further complicating the issue of misfueling. 
         [0009]    It is known in the art to overcome the misfueling problem by installing a misfueling inhibitor (MFI) in the fuel filler pipe assembly. One type of MFI has an aperture of a diameter which prevents entry of a fuel supply nozzle with too great a diameter. The MFI also has two or more latches arranged near a flapper door, the latches facing toward the opening. Walls of a fuel supply nozzle having a diameter in an appropriate range can depress all of the latches thereby allowing the door to open and fuel to be dispensed. A fuel supply nozzle of a smaller diameter engages fewer than all the latches at a time thereby preventing the flapper door from opening. Another type of MFI has an upper portion which blocks nozzles of too large a diameter. After making it through the upper portion, the nozzle encounters a ring with a slot removed, which is connected to a latching mechanism on a flapper door. A nozzle which is too small easily slides through the ring without unlatching the door. However, a large enough nozzle spreads the ring apart thereby unlatching the door allowing the nozzle to be inserted all the way through the MFI. In these non-limiting examples, only a fuel supply nozzle of the appropriate diameter, or small range in diameter, can both enter the MFI and actuate the latch(es) on the flapper door on the MFI. 
         [0010]    An automotive manufacturer with global customers wishing to prevent misfueling is obligated to provide a wide variety of fuel filler pipes with a range of MFIs for global supply. If a vehicle intended for a particular region has a fuel filler assembly with a MFI for that region is then transferred to another region requiring a different MFI than was installed, the entire fuel filler assembly need be replaced. 
       SUMMARY 
       [0011]    To solve at least one problem in the prior art, a fuel fill assembly adapted to be installed into a fuel fill pipe of an automotive vehicle is disclosed which has an upper piece including an upper selectively-openable closure and a lower piece including a lower selectively-openable closure. The upper piece releasably couples with the lower piece. The upper closure includes: an upper seal, a frame defining an upper port adapted to accept a fuel supply nozzle, an upper flapper door coupled to the frame by a hinge with the upper seal set into a groove in the upper flapper door, and a spring coupled between the upper flapper door and the frame. The spring urges the upper flapper door to a closed position with a force to cause the upper seal to deform against the frame. In an alternative embodiment, the upper seal is set into a groove in the frame. 
         [0012]    The lower closure includes: a frame defining a lower port, the lower port adapted to accept a fuel supply nozzle, a lower flapper door coupled to the frame by a hinge; and a seal set into a frame groove in the frame or a door groove in the upper flapper door, and a spring coupled between the lower flapper door and the frame. The spring urges the lower flapper door to a closed position with a force sufficient to deform the seal between the lower flapper door and the frame. 
         [0013]    The upper piece and lower piece are releasably coupled using a threaded connection, a bayonet coupler, a slot-and-tab coupler, a twist lock coupler, or any known removable coupling system can be employed. 
         [0014]    The fuel fill assembly, in one embodiment, is installed into an automotive vehicle having a fuel fill pipe. The fuel fill assembly includes a sealing member fitted onto an external surface of the lower piece. The sealing member, made of a resilient material, seals between an exterior surface of the lower piece and an interior surface of the fuel fill pipe. The lower piece may also include a fuel guide coupled downstream end of the lower piece. A fuel guide is optional depending on the geometry of the fuel fill pipe and the fuel dispensing systems provided in the region in which the vehicle is refueled. In other embodiments, the fuel fill assembly has valves to provide pressure and vacuum relief to the fuel system depending on the application. In some applications, vacuum relief can be achieved through the upper and lower sealing doors; thus, no pressure or vacuum relief is added. However, for pressure and lower vacuum relief, additional valves are included in the full assembly depending on system requirements in various markets. 
         [0015]    Also disclosed is a fuel fill assembly adapted to be installed into a fuel fill pipe of an automotive vehicle having upper and lower pieces. The upper piece includes: an upper frame defining an upper aperture adapted to accept a fuel supply nozzle, an upper articulating door coupled to the upper frame by an upper hinge, an upper spring coupled between the upper frame and the upper articulating door, and an upper seal between the upper articulating door and the upper frame. The lower piece includes: a lower frame defining a lower aperture adapted to accept the fuel supply nozzle, a lower articulating door coupled to the lower frame by a lower hinge, a lower spring coupled between the lower frame and the lower articulating door, and a lower seal between the lower articulating door and the lower frame. The lower and upper springs bias the lower and upper articulating doors to cover the lower and upper apertures, respectively. The lower and upper seals are deformed by force exerted by the lower and upper springs, respectively. 
         [0016]    The seals are located in a door groove or a frame groove. In one embodiment, the upper piece also includes a misfuel inhibitor located between the lower and upper articulating doors. The misfuel inhibitor prevents insertion of a fuel supply nozzle having a diameter that is outside of predetermined range. In another embodiment, the misfuel inhibitor is integrated with the upper articulating door. The misfuel inhibitor prevents opening of the upper articulating door by fuel supply nozzles having a diameter greater than an upper limit diameter and fuel supply nozzles having a diameter less than or equal to a lower limit diameter. In yet another alternative, the lower piece further has a misfuel inhibitor. Alternatively, the misfuel inhibitor is integrated with the lower articulating door to prevent opening of the lower articulating door by fuel supply nozzles having a diameter greater than an upper limit diameter and fuel supply nozzles having a diameter less than a lower limit diameter. 
         [0017]    As installed in an automotive vehicle having a fuel tank, the lower and upper articulating doors swing toward the fuel tank when opened. Pressure buildup in a space in between the lower and upper articulating doors exerts a closing force on the upper articulating door and an opening force on the lower articulating door. 
         [0018]    In one embodiment, the fuel fill assembly is installed into an automotive vehicle having a fuel fill pipe with a sealing member set into a circumferential groove in an external surface of the lower piece. The sealing member forms a seal between an exterior surface of the lower piece and an interior surface of the fuel fill pipe. 
         [0019]    Some prior art systems provide two doors in a fuel assembly with only a lower door having a seal. Such system largely prevents water from splashing into the space in between the two doors. However, it doesn&#39;t prevent water vapor from entering the upper door and condensing in the space between the two doors or from fuel vapors trapped between the two doors from vaporizing and exiting out the non-sealing upper door. Thus, such prior art systems are typically supplied with drains to remove water buildup. By providing two sealing doors, according to an embodiment of the present disclosure, water vapor and water are prevented from entering through the upper door obviating the need for a drain thereby reducing complexity, weight, and cost. 
         [0020]    Another advantage is that any excess fuel dripping off a fuel supply nozzle after a fueling operation is trapped between lower and upper doors. Because the doors both open inward, any pressure increase due to vaporization of the trapped fuel causes the upper door to be sealed with a greater force and cause the lower door to open, if the pressure due to vaporization is sufficient to act against the spring force. When the lower door opens, fuel vapors are introduced into the tank and its associated fuel vapor recovery system. Consequently, emission of such fuel vapors into the atmosphere is avoided. 
         [0021]    An advantage of the present invention is that the vehicle can travel through the assembly process with only the lower piece of the fuel assembly attached. Because the lower piece has a flapper door, debris is prevented from entering the fuel tank. But, fuel can be supplied to the vehicle through the flapper door. 
         [0022]    Yet another advantage of the present development is that if the upper piece of the fuel assembly needs to be replaced, for example by virtue of damage caused, for example, by vandalism or by the vehicle owner moving among regions with different fuel supply nozzle diameters, the entire fuel filler system need not be replaced. Instead, the existing upper piece of the fuel filler assembly can be decoupled from the lower piece and an appropriate replacement upper piece is coupled with the lower piece. In embodiments in which the lower and upper pieces can be decoupled nondestructibly, the replacement can be accomplished with minimal effort and cost and with minimal risk of destruction to the system and/or vehicle. In another embodiment, the upper piece is destroyed in the process of removal to avoid the possibility that it could be installed onto another vehicle for which it is not intended. In such an embodiment, the lower piece is unharmed in the process so that it can couple with a replacement upper piece of the appropriate specification for the region in which its operation is intended. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  shows a portion of a vehicle with a fuel tank; 
           [0024]      FIG. 2  shows a fuel fill assembly according to an embodiment of the disclosure; 
           [0025]      FIG. 3  shows a misfuel inhibitor according to the prior art; 
           [0026]      FIG. 4A  shows a flapper door with a groove according to an embodiment of the present disclosure; 
           [0027]      FIG. 4B  shows a cross section of the flapper door of  FIG. 4A ; 
           [0028]      FIG. 4C  shows a cross section of the flapper door cooperating with a frame; 
           [0029]      FIG. 5A  shows a flapper door according to an embodiment of the present disclosure; 
           [0030]      FIG. 5B  shows a cross section of the flapper door of  FIG. 5A  cooperating with a frame with a groove; 
           [0031]      FIGS. 6 and 7  show a portion of a lower piece according to an embodiment of the present disclosure; 
           [0032]      FIG. 8  shows a portion of an upper piece adapted to engage with lower piece of  FIG. 7  according to an embodiment of the present disclosure; and 
           [0033]      FIG. 9  is a cross section of lower piece of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION 
       [0034]    As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. The representative embodiments used in the illustrations relate generally to a capless fuel fill assembly for an automotive vehicle. However, the fuel fill assembly may be incorporated into various other types of vehicles, such as boats, private airplanes, etc. Those of ordinary skill in the art may recognize similar applications or implementations whether or not explicitly described or illustrated. 
         [0035]    In  FIG. 1 , a portion of an automotive vehicle  10  is shown which has a fuel fill pipe  12  leading to a fuel tank  14 . Inside the fuel fill pipe  12  is a fuel assembly  16 . 
         [0036]      FIG. 2  is a cross-sectional representation of fuel fill pipe  12  and the fuel fill assembly. The fuel fill assembly  16  includes an upper piece  18  and a lower piece  20 , which are releasably coupled together. That is, upper piece  18  can be decoupled from lower piece  20  while lower piece  20  remains installed within fuel fill pipe  12 . In  FIG. 1 , upper piece  18  and lower piece  20  are coupled together via a threaded connection  22 . Upper piece  18  and lower piece  20  seal at connection  22 . By a suitable selection of thread type, the threads can provide the desired seal. Alternatively, a resilient seal is provided at the connection between the two pieces. While a threaded connection is shown in  FIG. 2 , any suitable other connection alternative, can be used, in place of threads. For example, a tab-and-slot connection is provided between upper piece  18  and lower piece  20 , which is discussed in regards to  FIGS. 6-9 . 
         [0037]    Within upper piece  18 , a misfuel inhibitor  24  is installed. Misfuel inhibitor  24  is discussed below in more detail in relation to  FIG. 3 . In the embodiment shown in  FIG. 2 , upper piece  18  has an upper flapper door  26  located on the upstream end of upper piece  18  mating with a frame  27 , with flapper door  26  covering an upper port, or aperture, defined in frame  27 . Upper flapper door  26  has a hinge  28  about which upper flapper door  26  rotates to open. Upper flapper door  26  is biased toward a closed position by spring  30 . Upper flapper door  26  is also equipped with a seal  32 , shown as an  0 -ring in the embodiment in  FIG. 2 . Although upper piece  18  is shown in  FIG. 2  as having a misfuel inhibitor  24 , in some alternative embodiments, misfuel inhibitor  24  is integrated into an upper selectively-openable closure  33 . In other embodiments, misfuel inhibitor  24  is included in lower piece  20 . Or, in other embodiments, no misfuel inhibitor is installed. Upper selectively-openable closure  33 , in one embodiment, is an assembly including: door  26 , frame  27 , hinge  28 , spring  30 , and seal  32 . 
         [0038]    Continuing to refer to  FIG. 2 , lower piece  20  contains a lower flapper door  36  which rotates about a hinge  38 . As shown in  FIG. 2 , flapper door  36  is biased to a closed position in which flapper door  36  abuts frame  39 . Flapper door  36  is biased towards frame  39  by spring  40 . A lower port, or aperture, is defined in frame  39 ; the port is covered by flapper door  36 , as shown in  FIG. 2 . Seal  42  is deformed under force applied to door  36  by spring  40  to provide sealing. Seal  42  is shown as an  0 -ring in  FIG. 2 ; but such example is not intended to be limiting; other seal types are also contemplated. Fuel fill pipe  12  is coupled to fuel tank  14  (not shown in  FIG. 2 ). To prevent fuel tank vapors from being released from the vehicle by passing through the space between fuel fill pipe  12  and fuel assembly  16 , a sealing member  44  is placed between lower piece  20  and fuel fill pipe  12  and set into a groove  43  on lower piece  20 . In an alternative embodiment, a groove (not shown) is formed in fuel fill pipe  12  and sealing member  44  is placed in the groove in fuel fill pipe  12 . An additional seal, similar to sealing member  44 , can be positioned or placed at the top of pipe interfacing with upper piece  18  and frame  27  to substantially completely seal the inner diameter of fuel fill pipe  12  to protect against the intrusion of dust, dirt, debris water or any other corrosive elements. In some embodiments, tabs  46  are on the upper surface of lower piece  20 . As lower piece  20  is installed into fuel fill pipe  12 , tabs  46  are bend inwards and ride on the inside surface of fuel fill pipe  12 . When lower piece  20  is at its installed position, tabs  46  snap into slots  47  to secure lower piece  20  within fuel pipe  12 . Lower piece  20  is coupled to a flow guide  48 , which directs the fuel into fuel fill pipe  12  in such a way to substantially prevent backsplash. The guide is desirable where, due to geometry of the filler system on the vehicle or poor dispensing flow quality, backsplash is more prevalent. 
         [0039]    Any suitable misfuel inhibitor  24  can be employed. 
         [0040]      FIG. 3  shows an exemplary misfuel inhibitor  24  as seen from a downstream side, i.e., with the door opening outward. Various misfuel inhibitor  24  designs are known, such as those shown in US 2008/0237230 A1 and WO 2008/127916 A1, which are incorporated by reference in their entirety. Misfuel inhibitor  24  has a flapper door  50 , which is biased by coil spring  52  and rotates about bearing pin  54 . Across from pin  54 , flapper door  50  has a projection  53  which latches into notches  58  emanating from slot  60  of ring  62 . As shown in  FIG. 3  in which ring  62  is undisturbed, projection  53  prevents flapper door  50  from rotating open. However, when a cylindrical object, such as a fuel supply nozzle, of an appropriate diameter is inserted into misfuel inhibitor  24  (through the end not shown in  FIG. 3 ), the object causes ring  62  to spread apart along slot  60  allowing projection  53  to be released from notches  58  thereby allowing the flapper door  50  to open. Projection  53  and ring  62  with notches  58  provide a non-limiting example of a latching device that can be included in a misfuel inhibitor  24 . 
         [0041]    As described above, misfuel inhibitor  24  can be integrated into upper selectively openable closure  33 . Alternatively, misfuel inhibitor  24  can be integrated into lower selectively openable closure (includes door  36 , spring  40 , hinge  38 , seal  42 , and frame  39 ). 
         [0042]    In  FIG. 4A , a flapper door  100  is shown which has a plate  102  with a groove  104  into which a seal can be placed, molded or manufactured. Flapper door  100  may represent either one or both of doors  26  and  36 . Flapper door  100  has arms with holes  108  through which a pin can be inserted, for flapper door  100  to rotate about to open and close off a fuel filler port. A cross section of plate  102  with groove  104  is shown in  FIG. 4B . In  FIG. 4C , a cross section of plate  102  is shown with the groove having a seal  110  inserted. Seal  110  is overmolded into the groove or provided by any known process. Seal  110  in  FIG. 4C  is shown proximate frame  112 , also shown in cross section. Frame  112  has a port defined therein. Plate  102  of flapper door  100  cooperates with frame  112 , in particular, a spring force (spring not shown) biasing plate  102  toward frame  112  causes seal  110  to deform to seal between the two sides of plate  102 . The cooperation of seal  110  with frame  112  seals off the port defined in frame  112 . 
         [0043]    Alternatively, the seal is applied to the frame as shown in  FIGS. 5A and 5B . A flapper door  120  has a plate  122  with arms  126  and holes  128  to accommodate a pin about which flapper door  120  can rotate. A spring (not shown) can be associated with the pin and flapper door  120  to cause flapper door  120  to be biased toward a closed position. A cross section of plate  122  is shown in  FIG. 5B  proximate to a frame  132  which has a port defined therein. Frame  132  has grooves in which seal  134  is affixed. Seal  134  can be overmolded onto frame  132 ; alternatively, any other process known to one skilled in the art can be used. Due to spring force, seal  134  is deformed against plate  122  to seal between the two sides of plate  122 . Frame  132  may represent either frame or both frames  27   39 . 
         [0044]    In  FIG. 6 , one inner piece  200  of a tab and slot coupler is shown. There are engagement features  202  which each have an installation guide  204  and an orifice  206 . Indexing features  208  are included to aid in indexing engagement features  202  properly during installation. 
         [0045]    A portion of the circumference of lower piece  200  is shown in  FIG. 7 . The piece is shown flat for the purposes of illustrating the coupling joint. In  FIG. 7 , there is a ramp portion  209 . The ramp cannot be seen from this view, but will become apparent in regards to  FIG. 9 .  FIG. 8  shows a portion of an upper piece  210 . It has a raised portion  212 , which couples with installation guide  204  when moved in the direction of arrow  214 . A raised button  216  is partially surrounded by break out orifices  218 . As shown, raised button  216  is connected to upper piece  200  on about one-third of the periphery and is contiguous to orifices  218  for about two-thirds of the periphery. 
         [0046]    In  FIG. 9 , a cross-section of lower piece  200  is shown. Orifice  206  is visible. The ramp of ramp portion  209  can be seen from the view in  FIG. 9 . During assembly, upper piece  210  moves relative to lower piece  200 , as illustrated by arrow  214  in  FIG. 8 . Button  218  rides on ramp  209  until it falls into orifice  206 . Lower piece  200  and upper piece  210  flex as button  218  rides over ramp  209  during assembly. Upon disassembly, however, button  218  is held in place by the thick section, t, of ramp  209 . Button  216  is torn out of lower piece  200  during disassembly. Orifices  218  allow some flex of button  216  within lower piece  200  during assembly to negotiate ramp  209 . However, orifices  218  weaken the connection between button  216  with upper piece  210  such that button  216  rips out upon removal. This ensures that upper piece  210  is not reused in an improper application. 
         [0047]    While the best mode has been described in detail with respect to particular embodiments, those familiar with the art will recognize various alternative designs and embodiments within the scope of the following claims. While various embodiments may have been described as providing advantages or being preferred over other embodiments with respect to one or more desired characteristics, as one skilled in the art is aware, one or more characteristics may be compromised to achieve desired system attributes, which depend on the specific application and implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. The embodiments described herein that are characterized as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications.