Abstract:
The invention is based on the insight that a filling system obtained by combining a “Kruse” compatible threaded socket and an annular magnet as required for the operation of the “Elaflex” nozzle, will exhibit air exchange problems related to the difference in the positioning of the respective air intake openings of the “Kruse” bottle and the “Elaflex” nozzle. More particularly, the invention is based on the insight that by judiciously providing a chamber in fluid communication with the volume of air or vapor in the tank, filling may be made possible with a “Kruse” bottle as well as with an “Elaflex” nozzle.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application is a continuation of U.S. patent application Ser. No. 13/502,444, filed Apr. 17, 2012, which is a U.S. national stage entry under 35 U.S.C. §371 of International Application No. PCT/EP2010/065477, filed Oct. 14, 2010, which claims priority to European application No. 09173578.7, filed on Oct. 21, 2009. The disclosures of all of the aforesaid applications are incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention pertains to the field of filling systems for fluid tanks of motor vehicles, and more particularly systems for filling a tank with urea for use in vehicular emission control systems. 
         [0004]    2. Description of the Related Art 
         [0005]    As is generally known, motor vehicles require several different fluids for their operation, which may include fuel, cooling fluids, and urea. A general concern in the design of containers for these fluids is the need to prevent inadvertent filling of a container with a different fluid than the one for which it is intended. Such an erroneous fill-up can seriously damage the system that receives the wrong fluid, and, in the case of fluids for emission control systems such as urea-based NOx decomposition systems, it may cause non-compliance to the emission standards which the system in question is intended to ensure meeting. 
         [0006]    Another concern in the design of filling systems for containers of vehicle fluids is the need to remove any vapor or gas present in the container during the process of filling the container with the desired fluid. 
         [0007]    With respect to urea tanks, used for example in vehicles adapted to remove the NOx from the engine&#39;s exhaust fumes, the above concerns are addressed by two known systems. 
         [0008]    The “Elaflex” system dispenses a urea solution from a nozzle spout with a diameter of approximately 19 mm and a compatibly sized socket mounted on the tank to receive the nozzle. The diameter of the socket is chosen in such a way that use of a standardized diesel or gasoline nozzle is physically prevented. Furthermore, in an approach similar to the one disclosed in U.S. Pat. No. 5,562,133 to Mitchell, the Elaflex socket contains a magnet of annular shape that cooperates with a magnetically actuated valve in the nozzle to authorize its operation. A disadvantage of the “Elaflex” system is that filling can only take place at a compatible filling station. 
         [0009]    The “Kruse” system dispenses a urea solution from a bottle, which is screwed in an inverted position onto a threaded socket mounted on the tank. To allow the fluid to flow out of the “Kruse” bottle and into the tank, the bottle must be pressed down in order to switch the valve mounted on the bottle&#39;s protruding axis into an open position. The system will then on the one hand provide a flow of urea solution from the bottle into the tank, and on the other hand provide a corresponding flow of air and vapor from the tank to the bottle. A disadvantage of the “Kruse” system is that the fluid is dispensed rather slowly, compared to the “Elaflex” system. 
         [0010]    Whereas each of the systems described above has its own advantages and disadvantages, some of which may be more pertinent to particular users than to others, it is particularly inconvenient and disadvantageous that vehicle designers have to choose compatibility with a single system, thereby precluding the use of the other system by the end user. 
       SUMMARY 
       [0011]    It is an object of the present invention to reconcile the authorization system based on the presence of a annular magnet with a bottle-based system requiring a coupling. 
         [0012]    This object is reached by the operation of the characterizing features of the independent claims. 
         [0013]    The invention is based on the insight that a filling system obtained by combining a “Kruse” compatible threaded socket and an annular magnet as required for the operation of the “Elaflex” nozzle, will exhibit air exchange problems related to the difference in the positioning of the respective air intake openings of the “Kruse” bottle and the “Elaflex” nozzle. More particularly, the invention is based on the insight that by judiciously providing a chamber in fluid communication with the volume of air or vapo the tank, filling may he made possible with a “Kruse” bottle as well as with an “Elaflex” nozzle. 
         [0014]    According to an aspect of the present invention, there is provided a fitting for the filling opening of a vehicular fluid tank, comprising a tubular main body having a first end for connection with said tank and a second end adapted to receive a spout, the main body being adapted to be equipped with a magnet substantially spanning the circumference of said main body for authorizing a flow in said spout, and a tubular coupling section at said second end, wherein said tubular coupling section is adapted to detachably couple to a bottle having a fluid outlet and an air intake, wherein the fitting comprises a chamber between the second end and the magnet, wherein, when in use, an end of a first ventilation conduit is present in the chamber, the first ventilation circuit being in fluid communication with a volume of gas present at the tank side of the fitting, such that in the coupled position of the bottle the air intake is located in the chamber and the fluid outlet flows out in the direction of the first end, and wherein, in use, an end of a second ventilation conduit is present in the tubular main body on the tank side of the magnet, the second ventilation conduit being in fluid communication with the volume of gas present at the tank side of the fitting. 
         [0015]    European Patent 1 502 794 to Jost Automotive GmbH discloses a device for avoiding wrong refueling in motor vehicles, in particular in relation to containers for urea. This device consists of a fitting for receiving a spout, the fitting including a magnet as used in the “Elaflex” system. The tank opening exhibits a protrusion with an outer thread to receive a cap. 
         [0016]    In an exemplary embodiment of the fitting of the present invention, the bottle is a screw-on bottle, and said tubular coupling section has a thread for detachably coupling to the bottle. In a particular embodiment, the tubular coupling section is adapted for being coupled with a Kruse bottle, such that the fluid outlet substantially seals the chamber from the first end in the coupled position of the Kruse bottle. This embodiment has the advantage that it allows the vehicle&#39;s operator to use either an “Elaflex” dispenser or a “Kruse” bottle, depending on the availability of either source, with the same tank, while still preventing a filling of the tank with improper fluids. 
         [0017]    In an exemplary embodiment of the fitting of the present invention, the tubular main body comprises a peripheral groove for holding the magnet, and one of the first ventilation conduit and the second ventilation conduit extends substantially axially through said groove. In a particular embodiment, said one of said first ventilation conduit and said second ventilation conduit is embedded in an axial ridge intersecting said radial groove. 
         [0018]    The fluid communication between the chamber and the volume of gas present at the tank side of the fitting may be provided by the combined operation of the first ventilation conduit and the second ventilation conduit, i.e., the first ventilation conduit may provide fluid communication between the chamber and the tank side of the main body, which is in fluid communication with the volume of gas via the second conduit. 
         [0019]    The fluid communication between the tank side of the main body and the volume of gas present at the tank side of the fitting may be provided by the combined operation of the first ventilation conduit and the second ventilation conduit, i.e., the second ventilation conduit may provide fluid communication between the tank side of the main body and the chamber, which is in fluid communication with the volume of gas via the first conduit. 
         [0020]    In a more particular embodiment, the fitting comprises a magnet consisting of an interrupted ring situated in said peripheral groove, wherein the interruption is adapted to flank said one of said first ventilation conduit and said second ventilation conduit. In a more particular embodiment, the interrupted ring extends over a sector measuring between 20° and 40°. A sector in this range balances the proper operation of the magnet with a limited pressure drop between the compartments. It is an advantage of this embodiment that only a single ventilation conduit passes on the outside of the main body, while the other ventilation. conduit provides ventilation between the tank side and the coupling side of the main body with a minimal use of space and ensuring a relatively high flow level. 
         [0021]    In an exemplary embodiment, one of said first ventilation conduit and said second ventilation conduit is formed by a central cavity of the tubular main body, said central cavity receiving a part of the bottle in the coupled position, wherein the central cavity is dimensioned with a radius that exceeds a radius of the received part of the bottle in an amount sufficient to provide fluid communication between the chamber and the tank side of the main body. 
         [0022]    The fluid communication between the chamber and the volume of gas present at the tank side of the fitting may be provided by the combined operation of the first ventilation conduit a d the second ventilation conduit, i.e., the first ventilation conduit may provide fluid communication between the chamber and the tank side of the main body, which is in fluid communication with the volume of gas via the second conduit. 
         [0023]    The fluid communication between the tank side of the main body and the volume of gas present at the tank side of the fitting may be provided by the combined operation of the first ventilation conduit and the second ventilation conduit, i.e., the second ventilation conduit may provide fluid communication between the tank side of the main body and the chamber, which is in fluid communication with the volume of gas via the first conduit. 
         [0024]    In an exemplary embodiment, the fitting of the present invention comprises a funnel shaped section at the first end. 
         [0025]    In an exemplary embodiment, the fitting of the present invention comprises a connecting flange near the second end, and the tubular coupling section protrudes beyond the flange. 
         [0026]    In an exemplary embodiment, the fitting of the present invention comprises a constricted zone with a reduced inner diameter, substantially equal to the diameter of the spout and the outlet of the bottle. 
         [0027]    An exemplary embodiment of the present invention provides a vehicular fluid tank comprising a fitting according to the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    The foregoing and other advantages of the present invention will be further clarified in relation to the enclosed Figures, in which: 
           [0029]      FIG. 1   a  illustrates a fitting according to the prior art “Elaflex” filling system; 
           [0030]      FIG. 1   b  provides an exploded view of the fitting of  FIG. 1   a,  drawing attention to the presence of an annular magnet therein; 
           [0031]      FIG. 2  provides a sectional view of a fitting according to the prior art “Kruse” filling system; 
           [0032]      FIGS. 3-6  provide sectional views of various embodiments of a fitting according to the invention, drawing attention to the different parts of the main body to be ventilated;  FIG. 7  illustrates an essentially annular magnet with a sector-shaped opening of approximately 40° as characteristic of an embodiment of the present invention; 
           [0033]      FIG. 8  illustrates a substantially annular magnet composed of three parts extending over approximately 100° each, as characteristic of an embodiment of the present invention; 
           [0034]      FIG. 9  illustrates an exemplary embodiment of a fitting according to the invention with a flange; and 
           [0035]      FIG. 10  illustrates an exemplary embodiment of a fitting attached to a vehicle vehicular fluid tank. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0036]      FIG. 1  illustrates fitting  100  according to the prior art “Elaflex” filling system. In  FIG. 1   a,  the fitting  100  is assembled for use, while  FIG. 1   b  provides an exploded view, drawing attention to the different parts comprised in the fitting. The “Elaflex” fitting  100  is equipped with a ring magnet  102 , the magnetic field of which acts on a magnetically actuated switch present in an “Elaflex” compatible spout. Only when an appropriate magnetic field is applied to this switch, a flow of urea solution through the spout is authorized. This prevents filling up a tank intended for a different fluid with a urea solution, because other tanks would not be equipped with a magnet. The circular symmetry of the magnetic field provided by the ring magnet  102  ensures proper operation regardless of the angular positioning of the fitting in the fluid tank, and regardless of the angular positioning of the spout in the fitting. 
         [0037]    A further preventive measure against inadvertent filling of the urea tank with a different fluid is provided by the diameter of the inner tube  103  of the fitting  100 . The diameter of this inner tube  103  is less than the diameter of a standardized spout for dispensing gasoline or diesel fuel. Hence, it is mechanically impossible to enter such a fuel spout in the fitting  100  of a urea tank. 
         [0038]    The “Elaflex” spout will shut off when it detects that the level of liquid in the tank has reached the spout. More specifically, the spout will shut off when the spout opening is no longer in contact with air, i.e. no longer ventilated. This implies a need for proper ventilation of the space in which the spout opening is placed, in order for the spout to function properly up to the point where the tank is full. 
         [0039]    Furthermore, the air and/or vapor present in the tank needs to be able to escape from the tank at the rate at which the urea solution is fed into it. If the spout is not equipped with an internal vapor recovery system, these gases will typically escape through the part of the inner tube  103  that is not obstructed by the spout. It is therefore important that the air and/or vapor be allowed to efficiently reach the opening at the tank side of the fitting. 
         [0040]    The above ventilation constraints are easily met with the “Elaflex” fitting illustrated in  FIG. 1 , because it is relatively short and straight, posing no particular obstruction for the described air return paths. 
         [0041]      FIG. 2  illustrates an embodiment of a fitting according to the “Kruse” system. 
         [0042]      FIG. 3  illustrates an embodiment of the fitting according to the present invention. 
         [0043]    The fitting  300  comprises a tubular main body  301  having a first end  302  for connection with said tank and a second end  303  adapted to receive a spout. Optionally, the tubular main body  301  has a funnel shaped section  308  at the first end  302 . 
         [0044]    The fitting may be produced from polyamide, polyethylene, or other materials with suitable properties. As illustrated in  FIG. 10 , the fitting may be permanently attached to the filling opening of a fluid tank by means of welding or any other suitable attachment process. Alternatively, the first end may be formed as a hose tail for attaching a flexible hose leading to the fluid tank. 
         [0045]    The main body  301  is adapted to be equipped with a magnet  304  substantially spanning the circumference of the main body  301  for authorizing a flow in the spout. The fitting further comprises a tubular coupling section  305  at said second end  303 . The tubular coupling section  305  is adapted to detachably couple to a bottle such that a protruding part of this bottle substantially seals the fitting both near the tubular coupling section  305  and near the magnet  304 , thus creating a closed chamber  307  between the tubular coupling section  305  and the magnet  304 . 
         [0046]    As illustrated in  FIG. 9 , the tubular coupling section  305  is optionally provided in the form of a threaded protrusion extending beyond a plane or a flange at the second end  303 . 
         [0047]    In the embodiment illustrated in  FIG. 3 , a first ventilation conduit  306  is embedded in a ridge passing through a constricted zone  311  holding the magnet  304 . The main body  301  is also ventilated at the tank side, outside the chamber  307 . A second ventilation conduit  309  is provided for this purpose. The second ventilation conduit  309  is in fluid communication with a volume of gas present at the tank side of the fitting. The first ventilation conduit  306  is in fluid communication with that volume of gas via the second ventilation circuit  309 . 
         [0048]    It is possible to achieve a similar result with a configuration in which the first ventilation circuit provides direct fluid communication between the chamber  307  and the volume of gas at the tank side, the first ventilation conduit passing on the outside of the main body  301 , and in which the second ventilation conduit is embedded in a ridge passing through the constricted zone  311  holding the magnet  304 . The second ventilation conduit  306  is in fluid communication with the volume of gas at the tank side via the first ventilation circuit  309 . 
         [0049]    In the embodiment illustrated in  FIG. 4 , the first ventilation conduit  306  and the second ventilation conduit  309  are bifurcations of a single ventilation conduit  310  in fluid communication with a volume of gas present at the tank side of the fitting  300 . 
         [0050]    In the embodiment illustrated in  FIG. 5 , the fitting comprises a first ventilation conduit  306  ending in the chamber  307 , the first ventilation conduit  306  being in fluid communication with a volume of gas present at the tank side of the fitting The main body  301  is also ventilated at the tank side, outside the chamber  307 , by means of separate second ventilation conduit  309 . The second ventilation conduit  309  is also in fluid communication with a volume of gas present at the tank side of the fitting. 
         [0051]    In the embodiment illustrated in  FIG. 6 , the first ventilation conduit  306  is formed by a central cavity of the tubular main body  301 , the central cavity receiving a part of the bottle  312  in the coupled position, wherein the central cavity is dimensioned with a radius that exceeds a radius of the received part of the bottle  312  in an amount sufficient to provide fluid communication between the chamber  307  and the tank side of the fitting. 
         [0052]    It is possible to achieve a similar result with a configuration in which the first ventilation conduit  306  provides direct fluid communication between the chamber  307  and the volume of gas at the tank side, the first ventilation conduit passing on the outside of the main body  301 , and in which the second ventilation conduit is formed by a central cavity of the tubular main body  301 , the central cavity receiving a part of the bottle  311  in the coupled position, wherein the central cavity is dimensioned with a radius that exceeds a radius of the received part of the bottle  311  in an amount sufficient to provide fluid communication between the chamber  307  and the tank side of the main body. The second ventilation conduit  306  is in fluid communication with the volume of gas at the tank side via the first ventilation circuit  309 . 
         [0053]      FIG. 7  provides a perspective view of a magnet in the shape of an interrupted ring, as may be used in the embodiment illustrated in  FIG. 3 . The sector over which the ring is interrupted preferably measures between 20° and 40°. 
         [0054]      FIG. 8  provides a perspective view of a magnet in the shape of a ring with two interruptions, i.e., a magnet consisting of three separate sector-shaped elements. The concept of a substantially annular magnet or a magnet consisting of an interrupted ring, as used in the present application., must be understood to also refer to combinations of multiple parts, substantially extending along a ring, as illustrated in an exemplary way in  FIG. 8 .