Abstract:
A tank which has at least one at least partially electrically conductive container, an electric component arranged in the fuel tank, and a cover to close an opening for the electric component, the tank allowing grounding in a simple manner.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority 35 U.S.C. §119 to European Patent Publication No. EP 13188994.1 (filed on Oct. 16, 2013), which is hereby incorporated by reference in its entirety. 
       TECHNICAL FIELD 
       [0002]    Embodiments relate to a tank, more specifically a fuel tank, such as, for example, a fuel tank for a motor vehicle. Such a tank may include at least one at least partially electrically conductive container, an electric built-in component, which is arranged within the tank, and a cover to close an opening for the electric component. 
       BACKGROUND 
       [0003]    In tank systems, there is a requirement to provide grounding of the tank to carry away or prevent a possible static charge in the vehicle. In the case of steel tanks, this grounding is usually achieved either externally by attaching bolts with nuts and/or lugs to the tank. The bolts and/or lugs may be connected to the ground with the aid of an grounding strip, or internally using bolts and/or lugs and an grounding strip which is connected to the ground of an electric built-in component, e.g., a delivery module. 
         [0004]    Welding bolts and/or lugs and installing the grounding strip as well as making enquiries to ensure that installation has been carried out leads to increased costs. In the case of a service, there is the risk that a lack of grounding will arise in the absence of a connection with the ground line. 
         [0005]    A known fuel supply system with grounding is disclosed in German Patent Publication No. DE 10 2007 021 584 A1. As illustrated in  FIG. 1 , the known fuel supply system comprises a cover  3 , which is mounted on the upper surface of a fuel tank  1  in order to close an opening  4  formed in the upper wall. The cover  3  is produced from a plastic and comprises a tubular section which extends into the interior of the fuel tank container  11 . A pump housing  16  is mounted on the lower end of the tubular section. A fuel pump  2  is arranged within the pump housing  16 . A control unit  18  to control a motor of the fuel pump  2  is accommodated within a recessed section. The control unit  18  comprises an ground terminal. An electrically conductive wall of the tubular section is electrically connected to the ground terminal of the control unit  18 . In this prior art example too, the installation of the grounding and the insertion of the grounding spring is associated with a high outlay. Moreover, an additional, loose component is required to establish the connection between the pump and the tank. 
       SUMMARY 
       [0006]    Embodiments relate to a tank having grounding which is accomplished reliably and without the additional installation of individual components. 
         [0007]    Embodiments relate to a tank, more specifically a fuel tank, such as, for example, a fuel tank for a motor vehicle. The fuel tank may include at least one of: an at least partially electrically conductive container, an electric built-in component arranged within the fuel tank, a cover to close an opening for the electric built-in component and which includes at least one plug connection, and a grounding strip to connect an grounding pin of a plug connection to at least one conductive region of the fuel tank, wherein the opening is formed in an upper section of the fuel tank. 
         [0008]    Via the power supply of the electric component, there is a ground connection directly to the ground body of the vehicle. By connecting the ground connection and connecting the power supply to the closure cover on the tank, a reliable and maintenance-neutral ground connection is made available. 
         [0009]    The solution in accordance with embodiments has the advantage that the fuel tank contains a grounding strip which is moulded into the plastic of the cover. This measure reduces the number of parts since the grounding strip is moulded reliably into the cover. The risk that the ground connection will no longer exist after servicing is also minimized. 
         [0010]    It is advantageous if the grounding strip is designed in such a way that it is partially moulded onto the surface of the cover. By this means, direct contact with the tank is established via the closure part and a reliable ground connection is made possible. 
         [0011]    It is advantageous if the grounding strip is composed of a metal film. A metal film can easily be placed as an insert in the injection mould for the cover and then overmoulded. 
         [0012]    It is furthermore advantageous if the grounding strip is produced from a conductive plastic. The cover can then be produced in a simple manner by a two-component injection moulding method. 
         [0013]    It is advantageous if the fuel tank with the cover has a ground pin which establishes the ground connection to the grounding strip. 
         [0014]    In accordance with embodiments, a tank may include at least one of: a container which is at least partially electrically conductive and which forms a tank wall; an electric built-in component arranged in the tank; a cover to close an opening formed in a section of the tank for the electric built-in component, the cover including at least one plug connection having a ground pin; and a grounding strip to connect the ground pin of to at least one conductive region of the container. 
         [0015]    In accordance with embodiments, a vehicle fuel tank may include at least one of: a container which is at least partially electrically conductive and which forms a tank wall; a fuel pump arranged in the container; a cover to close an opening formed in a section of the tank for the fuel pump, the cover including at least one plug connection having a ground pin; a grounding strip to connect the ground pin of to at least one conductive region of the container; and a receiving ring to establish a ground connection between the grounding strip and the container. 
         [0016]    In accordance with embodiments, a fuel tank may include at least one of: a container which is at least partially electrically conductive and which has an opening; a fuel pump arranged in the container; a cover to close an opening formed in a section of the tank for the fuel pump component, the cover including an outer flange region and a ground pin; a grounding strip to connect the ground pin of to at least one conductive region of the container, the grounding strip extending along a surface of the outer flange region; and a receiving ring to connect the cover to the container and establish a ground connection between the grounding strip and the container. 
     
    
     
       DRAWINGS 
         [0017]    Embodiments will be illustrated by way of example in the drawings and explained in the description below. 
           [0018]      FIG. 1  illustrates a fuel tank of the prior art. 
           [0019]      FIG. 2  illustrates a plan view of a cover in accordance with embodiments. 
           [0020]      FIG. 3  illustrates a section through the cover in accordance embodiments. 
       
    
    
     DESCRIPTION 
       [0021]    The solution in accordance with embodiments is illustrated in an example from  FIGS. 2 and 3 . 
         [0022]      FIG. 2  illustrates a plan view of a cover  3  having an outer flange region  3   b , which forms a rim. In the illustrative embodiment, the inner region  3   a  of the cover arches towards the rear out of the plane of the drawing. The cover  3  is to close an opening in a fuel tank, e.g., a service opening for a fuel pump or some other electric built-in component. In this illustrative embodiment, the cover has openings  6 , which are provided, for example, for a fuel line. 
         [0023]    A plug connector  5  is indicated in the lower region of the cover  3 . The plug connector  5  has a plurality of pins. Via the plug connector  5 , the electric built-in component is supplied with electric energy. A grounding strip  7 , which extends from the ground pin  8  to the flange of the outer flange region  3   b,  is depicted in dashed lines. Here, the shape illustrated, by way of example, is curved or kinked, but a straight line connection between the ground pin  8  and the outer flange region  3   b  may also be advantageous. 
         [0024]      FIG. 3  illustrates the cover  3  with the inner flange region  3   a  and the outer flange region  3   b.  The section furthermore illustrates a terminal, which is mounted in one of the openings  6 . The ground pin  8  extends from the upper side of the inner region  3   a  at least as far as the grounding strip. The grounding strip  7  is overmoulded within the plastic layer of the inner region  3   a.  It extends from the ground pin  8  to the rim of the cover  3 . There, it follows the design, which in this case is step-shaped, and extends upwards in the plastic and emerges at the surface in region  7   b.  In region  7   b,  the grounding strip  7  is overmoulded only on one side as it extends over the surface of the flange region  3   b.  This results in the grounding strip  7  extending over its entire extent in a region  7   a  in which it is overmoulded on both sides and is mounted on the surface only in the region of the outer flange region  3   b,  in which it needs to come into contact with the closure part. 
         [0025]    The installation of the cover  3  in the fuel tank  1  is further indicated in  FIG. 3 . The container  11  of the fuel tank  1  has a receptacle  9 . This receptacle  9  may either be impressed in the material or applied in some other way, e.g., by being welded on. The cover  3  rests against the receptacle  9 , and is connected to the container  11  by way of a suitable receiving ring  10 . It is possible here to use a screwed receiving ring  10  or to configure the receptacle  9  and the receiving ring  10  in such a way that a snap joint can be produced. 
         [0026]    By way of the receiving ring  10 , which may be composed of a metallic material, at least on the inside thereof, the ground connection between the grounding strip  7 , which extends along the surface of the outer flange region  3   b,  and the container  11  of the fuel tank is established. In accordance with embodiments, a metal grounding strip  7  may be used, and placed in the injection mould and overmoulded in the production of the cover  3 . During this process, two different regions are produced: a region  7   a  overmoulded on both sides and a region  7   b  overmoulded on one side. An alternative solution is a two-component production of the cover  3 . In this process, a conductive region composed of a conductive plastic may be injected onto a first plastic component, which serves as an insulator, and the conductive region, in turn, is covered by an insulating plastic. 
         [0027]    The ground pin  8  illustrated in  FIG. 3  can be part of a plug connector. In the simplest case, the plug connector  5  may be used to supply energy to an electric built-in component. The plug connector  5  is not depicted in  FIG. 3 . It is also not absolutely essential for the implementation of embodiments. It would also be possible to configure embodiments in such a way that a ground pin is connected to the vehicle by a separate ground lead and is not used in combination with an electric lead. It is also not essential that the fuel tank  1  should be composed completely of a metallic material. It is also possible to use a fuel tank  1  partially comprising plastic. 
         [0028]    The embodiment has been described with reference to a fuel tank  1  but can be applied to any tank that requires grounding. 
         [0029]    The term “coupled” or “connected” may be used herein to refer to any type of relationship, direct or indirect, between the components in question, and may apply to electrical, mechanical, fluid, optical, electromagnetic, electromechanical or other connections. In addition, the terms “first,” “second,” etc. are used herein only to facilitate discussion, and carry no particular temporal or chronological significance unless otherwise indicated. 
         [0030]    Those skilled in the art will appreciate from the foregoing description that the broad techniques of the embodiments may be implemented in a variety of forms. Therefore, while the embodiments have been described in connection with particular examples thereof, the true scope of the embodiments should not be so limited since other modifications will become apparent to the skilled practitioner upon a study of the drawings, specification, and following claims. 
         [0031]    LIST OF REFERENCE SIGNS 
         [0032]      1  fuel tank 
         [0033]      2  fuel pump 
         [0034]      3  cover 
         [0035]      3   a  inner region 
         [0036]      3   b  flange region 
         [0037]      4  opening 
         [0038]      5  plug connector 
         [0039]      6  opening 
         [0040]      7  grounding strip 
         [0041]      7   a  grounding strip region (overmoulded on both sides) 
         [0042]      7   b  grounding strip region (overmoulded on one side) 
         [0043]      8  ground pin 
         [0044]      9  receptacle 
         [0045]      10  receiving ring 
         [0046]      11  container 
         [0047]      16  pump housing 
         [0048]      18  control unit