Abstract:
A fuelling fixture for vehicles includes a fuelling nipple configured to attach to a filling connection and a pot-like housing. The pot-like housing encloses the fuelling nipple and is configured to receive a filler cap enclosing the fuelling nipple.

Description:
FIELD OF THE INVENTION 
     The invention relates to a fuelling fixture for vehicles equipped with a fuelling nipple, to which a filling connection may be attached. 
     BACKGROUND OF THE INVENTION 
     Fuelling fixtures of this kind are already widely used for filling gas-powered vehicles. In this connection, particularly natural gas vehicles are increasingly gaining in importance due to their relatively low pollutant emissions and fuel consumption. On these vehicles, the fuelling fixture in mounted on the outside of the vehicle, but sometimes also on the inside of the vehicle or behind the body lids, in order to enable in this way a filling connection to be attached to the fuelling nipple of the vehicle. In this case, the fuelling fixture is connected to the gas tank of the vehicle by means of a high pressure hose. In this process, the fuelling nipple is often fastened to the vehicle body only by means of locknuts. 
     However, this attachment method bears a problem in that the fuelling nipple projects relatively far from the body area. Moreover, the filling opening of the fuelling nipple is often only closed with a plastic cap, which can, however, not fully prevent the fuelling nipple from getting dirty, especially when it is used in a dusty environment, or from freezing in winter. Therefore, there is a risk of foreign bodies or dirt particles entering the gas lines of the vehicle during fuelling, which can lead to excessive filter loading or even to inoperability. 
     SUMMARY OF THE INVENTION 
     It is therefore the object of the invention to provide a fuelling fixture for vehicles, which enables safe and secure installation und eliminates contamination of the fuelling nipple. 
     An aspect of the invention involves a fuelling fixture for vehicles. The fuelling fixture includes a fuelling nipple configured to attach to a filling connection and a pot-like housing. The pot-like housing encloses the fuelling nipple, and is configured to receive a filler cap enclosing the fuelling nipple. 
     The positioning of the fuelling nipple in a pot-like housing, into which a filler cap enclosing the fuelling nipple may be inserted or screwed, ensures complete covering of the fuelling nipple towards the outside. This ensures an absolutely dust-proof accomodation of the fuelling nipple. In addition, this pot-like housing, particularly in the embodiment having two housing sleeves fitted into each other, may be attached securely and stably to the body of the vehicle. This prevents any parts projecting from the body towards the outside, so that any risk of damage to the fuelling nipple is eliminated. 
     Moreover, it is preferred that upon insertion of the filler cap a sensor or micro-switch for immobilizing the vehicle is activated, which will prevent the vehicle from being started with the filling connection attached. Rather, the filling connection must be disconnected and the filler cap properly inserted in the pot-like housing for a starting of the vehicle to be possible. This safely prevents any accidents—as have already occurred in the past—occurring due to the vehicle being started and driven off whilst the filling connection is attached. 
     Further, by means of the filler cap screwed into the pot-like housing, a reliable seal is achieved, so that even in the case of a defective safety valve in the fuelling nipple, any uncontrolled escaping of gas is prevented. This is particularly important in cases where the fuelling fixture is installed in the passenger compartment or in a compartment in communication therewith (e.g. in the boot of a hatchback vehicle). The complete enclosure of the fuelling nipple thus allows a covered ventilation line to be connected to the pot-like housing in a simple manner, which can be used, if necessary, to branch of f any gas escaping from the fuelling nipple in a controlled manner to a safe place (e.g. under the bottom of the vehicle). 
     Further advantageous embodiments of the fuelling fixture are the subject matters of the subclaims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Three embodiment examples of the fuelling fixture will be explained and described below in more detail with reference to the drawings, wherein: 
     FIG. 1 shows a sectional view of a fuelling fixture; 
     FIG. 2 shows a fuelling fixture similar to FIG. 1, but with an additional ventilation line connected, and 
     FIG. 3 shows a rotated view of a further simplified fuelling fixture similar to FIG.  1 . 
     FIG. 4 shows another rotated view of a further simplified fuelling fixture similar to FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows a longitudinal section of a fuelling fixture  1 , in which a central, rotationally symmetrical fuelling nipple  8  is shown unsectioned. In this figure, reference literal A identifies the outlet side of the fuelling nipple  8 , while the fuelling side is identified by the reference literal B. From the fuelling side B, a filling connection (not shown), such as disclosed in European Patent 0 340 879, may be connected to the fuelling nipple  8 . It goes without saying that the filling connection is attached with the filler cap  4  removed. During fuelling, gas flows from the fuelling nipple  8  via a filling line  12  on the outlet side A to a tank (not shown) in the vehicle. 
     The fuelling fixture  1  has a bell—or pot-like housing  2  which surrounds the fuelling nipple  8 . Into this pot-like housing  2 , the above-mentioned filler cap  4  may be screwed, so that the fuelling nipple  8  is completely enclosed. The pot-like housing consists here of two also pot-like housing sleeves  2   a,    2   b  fitted into each other, such that due to the counter-directed screwing of the two housing sleeves  2   a  and  2   b  by means of several screws  6 , the pot-like housing  2  is fixed to the body  11  of the vehicle, of which a section is shown. As is evident from the bottom half of FIG. 1, the screws  6  provided on the front side C of the housing  2 , pull the radially inner housing sleeve  2   b  with a ring-shaped collar  2   c  against the outer housing sleeve  2   a,  whereby the body sheet  11  of the vehicle is clamped therebetween, so that the fuelling fixture  1  is securely fastened to the body  11 . Thus, the fuelling fixture  1  is essentially flush with the outer surface of the body  11 , with the filler cap  4  also terminating flush with the outer surface of the housing  2 . In this way, the detachable fasteners themselves, namely the screws  6  and the screw-fastening of the filling line  12 , are accomodated internally of the body, so that any manipulation is prevented. 
     The same applies to the screw-fastening of the fuelling nipple  8  by means of a union nut  8   b,  by which the fuelling nipple  8  rests in a secure manner with a ring-shaped flange  8   a  on the inner housing sleeve  2   b.  By this means, secure fastening of the fuelling nipple  8  is achieved. The outer housing sleeve  2   b  may also be made of plastics, since the large-area contact with the body sheet  11  provides secure support. Because screw-fastening with the filler cap  4  is preferred, the radially inner housing sleeve  2   b  is made of steel. On the bearing area of the housing sleeves  2   a  or  2   b,  a ring seal  3  is provided to ensure that they rest securely and in a sealing manner on the edge of the section of the body. Such a seal may also be provided on the opposite ring-shaped collar  2   c  of the inner housing sleeve  2   a.  Further, a ring seal  4   a  is provided between the inner housing sleeve  2   a  and the filler cap  4 , such that the interior of the fuelling fixture  1  is completely sealed. Preferably, the filler cap  4  is connected by means of a screw-thread  4   b,  but the screw-in movement may also be accomplished by bayonet fixing, or the cap may, as shown in FIG. 3, be simply inserted and locked by means of a lock  14  and a key  15 . 
     Additionally, several blind bores  5  are preferably provided in the filler cap  4 , which may be used for torsion identification or coding of the filler cap  4 . For instance, two such bores  5  may be arranged at an accurately defined pitch angle of e.g. 170°, so that the filler cap  4  can be opened only by means of a corresponding insertion key having pins offset at the same angle of 170° and fitting into bores  5 . An insertion key of this kind may preferably be located in a convenient manner at the filling connection or inside of the vehicle, so that this insertion key is always at hand when needed for fuelling. The first variant also allows a specific allocation of a certain type of gas or filling pressure to be realized. 
     Further, on the front side C a receptacle  7 ′ for a sensor  7  (see FIG. 2) is provided in the inner housing sleeve  2   b,  which sensor  7  determines the proper insertion state of the filler cap  4 . This ensures that, when the filler cap  4  is inserted, the fuelling fixture  1  is properly locked and disconnected from the filling connection. This sensor  7  may respond to contact with the filler cap  4 , since the latter is screwed in down to the micro-switch or the sensor  7 . Preferably, however, in order to prevent spark formation, the sensor  7  is formed as an inductive switch (e.g. as a Hall sensor or Reed contact), the filler cap consisting of a magnetizable material such as steel, so that the filler cap  4  activates the sensor  7  in the screwed-in position as illustrated here. This “activation” will always occur in such a manner that the vehicle is immobilized when the filler cap  4  is off, while the vehicle can be started when the filler cap  4  is properly inserted. 
     Moreover, a bore  13  serving as fluid passage is provided below the fastening nut  8   b  of the fuelling nipple  8 , which allows controlled ventilation from the interior D between the filler cap  4  and the fuelling nipple  8  to take place. For example, a thin hose may be connected here, which can be used to branch off any gas escaping in the case of a defective fuelling nipple  8  to a safe place. 
     FIG. 2 shows a preferred embodiment of the fluid passage  13 , the fuelling fixture otherwise having the same construction. Namely, a coaxial ventilation line  10  is fitted over the filling line  12 , which ventilation line is fixed to the connection thread  8   c  of the fuelling nipple  8  by means of a sleeve  10 ′. By means of a ring seal  9  between the sleeve  10 ′ and the union nut  8   b,  sealing towards the outside is achieved, so that any gas escaping from the fuelling nipple  8  may flow through the fluid passage  13  along the connection thread  8   c  to the ventilation line  10 , as indicated by a dashed and dotted line. To create this fluid passage  13 , it is e.g. sufficient to mill a narrow axial groove along the connection thread  8   c  of the fuelling nipple  8  up to the bearing surface  8   a,  so that a passage to the interior D is generated. 
     It is noted here again that due to the seal  4   a  in the area of the screw-thread  4   b  of the filler cap  4 , any escaping of gas towards the outside on the filling side B is securely prevented, while the ventilation line  10  may be guided to a safe place on the vehicle such under the bottom of the vehicle. In this connection, several seals  4   a  may also be provided on the outer perimeter or also on the front side of the filler cap  4 . 
     FIG. 3 shows a further simplified version of the fuelling fixture, which is otherwise constructed in a way similar to FIGS. 1 and 2. In this figure, the same reference numerals have been used for components having identical functions. FIG. 3 shows sectional views of the fuelling fixture, which are rotated relative to each other. In contrast to FIGS. 1 and 2, the screws  6  for fastening the threaded sleeves  2   a  and  2   b  together, which are fitted into each other, are screwed in from the interior D of the housing  2 . This simplifies the mounting operation of the housing substantially. In this case, the screws  6  engage in extensions  2   a  of the outer housing part  2   a.  Moreover, several reinforcement ribs  2   f  are provided on the inner housing part  2   b  in the corner area, which engage in corresponding grooves of the filler cap  4 . This solution is provided especially in cases where the filler cap  4  is not screwed into the housing  2 , but is locked, as shown in the bottom half, with a conventional lock  14  and key  16  (partially shown). During locking, a bolt  15  of the lock  14  engages in a ring-shaped groove of the fuelling nipple  8 , so that the filler cap is locked in the axial and torsional directions. However, the bolt  15  of the lock  14  could engage also in a corresponding profiled section of the housing  2 . 
     Of importance is further the embodiment of the outer housing sleeve  2   a  shown in the bottom half of FIG. 3, which has several spring-loaded catch hooks  2   d  on its perimeter. This enables the two housing parts  2   a  and  2   b  to be fitted together, with the catch hooks  2   d  engaging in the inner housing sleeve  2   b.  This enables fixing of the two housing sleeves  2   a  and  2   b  to each other during mounting and transport to be achieved. 
     Thus, a fuelling fixture  1 , which can be readily fixed to the vehicle body, is provided, which ensures particularly secure encapsulation of the fuelling nipple  8 . Thus, by means of the encapsulation, not only secure fastening but also complete dust-tightness of the fuelling nipple  8  is enabled, and freezing is securely prevented. Moreover, the components of the fuelling fixture  1  serve several functions, e.g. the filler cap  4  can activate the sensor  7  in a preferred manner for immobilisation, so that starting of the vehicle with the filler cap  4  removed is securely prevented.