Abstract:
A fuel sending unit protective cover assembly is disclosed, for protecting the fuel transducer module mounted to a fuel tank. The protective cover is associated with a locking ring. The locking ring engages the E-ring permanently secured to a fuel tank, by rotational engagement of the locking ring with one or more tabs protruding from the E-ring. The cover body with a plurality of descending legs is configured to engage ascending legs on the E-ring. The cover body is configured to permit installation and removal of the protective cover from the fuel tank without removal or disconnection of fluid conduits and electrical wiring.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates in general to a device for securing and protecting a fuel transducer module in relation to a fuel tank. 
       BACKGROUND 
       [0002]    A fuel transducer module is a common element in a fuel storage vessel, such as a fuel tank utilized in a vehicle. A fuel tank is a vessel having at least one filler opening and at least one outlet. Because the fuel tank is often mounted deep within the structure of a vehicle, and hence, not readily accessible or visible to the operator, a fuel level sensing unit or transducer is typically installed in the tank to transmit, electrically or mechanically, an indication of the quantity of fuel remaining in the tank. 
         [0003]    Because each opening in the fuel tank presents the opportunity for spillage or leakage, it is desirable to minimize the number of openings therein, and accordingly, fuel tank designs may utilize a unified transducer module which includes conduits for fuel and fuel vapors. The module fits over or within an opening in the tank, and is secured to the tank by appropriate seals to prevent leakage. 
         [0004]    In a typical mounting installation for a fuel transducer module, a “hard point” or anchor is permanently affixed to the tank. Typical of such attachment points is an imbedded or encapsulated ring, commonly referred to as an “E-ring” which may be molded into a plastic tank or welded to a metal tank. Such an E-ring typically surrounds a circular opening in the tank, and the fuel transducer module is engaged therewith. To hold the fuel transducer module in position on the tank in relation to the E-ring, a locking ring is provided which engages the E-ring and typically captures a flange on the fuel transducer module between the locking ring and the surface of the fuel tank. Typical of such installations is a fuel-sending unit and locking ring as described in U.S. Pat. No. 5,207,463, issued to Seizert, et al., and described in U.S. Patent Application Publication 2004/0021271, to Tratnik. 
         [0005]    A typical fuel transducer module presents one or more electrical connectors, usually in the form of an electrical union comprised of a socket and a plurality of conductors disposed in each. The transducer module also typically contains one or more fuel conduits or vents which communicate with the interior of the fuel tank. 
         [0006]    In recent years, vehicle crashworthiness standards have evolved which include regulations and engineering specifications designed to reduce the likelihood of fire or explosion in the event of a vehicular accident. In particular, a great deal of attention has been paid to fuel tank design, with due consideration to the positioning of the fuel tanks in vehicles, and the reduction of risk of damage to the fuel tank and its components in a collision. 
         [0007]    Because elements of the fuel transducer protrude outward from the surface of the fuel tank, it is desirable that those components be protected from impact during a collision. As a result, guards have been developed to surround the fuel transducer module, thereby offering a measure of protection against damage to the components of the module during a collision. 
         [0008]    Existing guards utilize either a stamped or drawn construction. These guards have a plurality of openings which allow electrical wiring and tubing to be connected from the vehicle in which the fuel tank is mounted to the fuel transducer module. The guards are typically mounted to the fuel tank or locking ring using threaded fasteners, such as studs. 
         [0009]    The design of currently known guards, however, presents certain practical limitations during fuel tank assembly and repair operations. Attachment of a guard utilizing threaded fasteners is time-consuming, and the manufacture of locking rings containing threaded fasteners is expensive. Additionally, currently known guards require the removal of the electrical connectors, fuel and vent lines from the transducer during the assembly or repair process. 
         [0010]    It is desirable, therefore, to provide a fuel-sending unit protective cover which can be easily attached to and removed from the fuel tank without the need for fasteners or tools, which is simple to manufacture and affordable, and which simplifies vehicle assembly and repair by being installable and removable without disturbing the electrical, fluid and vent connections between a vehicle and its installed fuel tank. 
         [0011]    It is an object of the present invention, to provide a protective guard to surround a fuel transducer module, and to protect said module against damage from external forces. 
         [0012]    It is further an object of the present invention to provide a guard which is easily formed from a single piece of material. 
         [0013]    It is a further object of the present invention to provide a guard which is easily and securely attached to a fuel tank and fuel transducer mounting ring without the need for fasteners, such as nuts, bolts or studs, and which can be affixed to a fuel tank without the use of numerous tools. 
         [0014]    It is a further object of the present invention to provide a guard for a fuel transducer module which is easily installed and removed from a fuel tank, while allowing the fuel transducer module to remain in place, and without requiring disconnection of conduits or electrical wiring harnesses from the transducer. 
       SUMMARY 
       [0015]    A fuel-sending unit protective cover is provided for protecting a fuel transducer module mounted to a fuel tank. The protective cover is associated with a locking ring. The locking ring engages the E-ring permanently secured to a fuel tank, by rotational engagement of the locking ring with one or more tabs protruding from the E-ring. A plurality of slots is provided on the locking ring to engage the tabs of the E-ring, and a fuel transducer module is captured between the surface of the fuel tank and the E-ring. 
         [0016]    A cover body with a plurality of descending legs is configured to engage ascending legs on the E-ring. The distal ends of the descending legs are provided with feet, which, in turn, engage spring clips mounted to the ascending legs of the locking ring. The body of the cover is provided with a socket for engagement with an installation and removal tool. 
         [0017]    The feet of the cover engage detents in the spring clips preventing unintentional rotation of the cover in relation to the E-ring. The cover and its associated legs are configured so that the legs do not interfere with the fuel transducer module when the cover is installed or removed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: 
           [0019]      FIG. 1  is a perspective view of a fuel transducer module associated with a locking ring, as taught in the prior art. 
           [0020]      FIG. 2  is a side view of the present invention in engagement with a locking ring, as positioned on a fuel tank. 
           [0021]      FIG. 3  is a perspective view of the surface of a fuel tank to which is attached a conventional E-ring. 
           [0022]      FIG. 4  is a perspective view of the present invention in partial engagement with the locking ring of the present invention. 
           [0023]      FIG. 5  is a perspective view of the protective cover and locking ring of the present invention in substantial engagement. 
           [0024]      FIG. 5A  is a detailed view of a first portion of the locking ring engaged with the protective cover. 
           [0025]      FIG. 5B  is a detailed view of a second portion of the locking ring engaged with the protective cover. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    The environment in which the invention operates is depicted generally at  FIG. 1 . A fuel tank  12 , typically constructed of either metal or plastic, is formed in the configuration of a generally closed vessel having a top, bottom, and sides. As depicted in  FIG. 1 , an attachment area  14  it is designated on one surface of the fuel tank  12  (usually a top surface) onto which a fuel transducer module  20  will be mounted. Typically, this area  14  of the fuel tank  12  is substantially flat and smooth. An opening is formed in the fuel tank  12  to accommodate portions of the fuel transducer module  20  including associated conduits  22  and fuel-level measuring elements (not shown). The transducer module  20  is also typically equipped with an electrical union  24  in the form of a socket equipped with a plurality of electrical conductors, designed to engage with a mating electrical plug (not shown). The transducer module  20  contains multiple conduits  22  for transmission of fuel, air and fuel vapors to and from the interior of the fuel tank  12 . All of the conduits  22  and electrical unions  24  are mounted to a unitary body, and the entire transducer module  20  is typically pre-manufactured and appropriately configured for the particular fuel tank installation of the type common to motor vehicles. It will be appreciated that fuel transducer modules  20  of this type are designed to be fully pre-assembled prior to installation on the fuel tank  12 . 
         [0027]    The fuel transducer module  20  body is typically cylindrical, having the necessary strength and thickness to provide sufficient mechanical support to the conduits  22  and electrical union  24  mounted to the upper surface of the module  20 , as well as to the conduits  22  and transducer elements mounted to and through the bottom of the transducer module  20 . 
         [0028]    With further reference now to  FIG. 1 ,  FIG. 2  and  FIG. 3 , the placement of the fuel transducer module  20  in relation to the fuel tank  12  will be best understood. To facilitate attachment, the fuel tank  12  is provided with an attached or embedded ring  40 , commonly referred to as an E-ring, and typically manufactured of metal appropriately formed and stamped. The E-ring  40  has an annular body  44 , and protruding therefrom at a plurality of locations around the circumference of the E-ring  40  is a series of tabs  46 . Each tab  46  has an upwardly extending ascender  48 , and a horizontal extension  50  which extends inwardly toward the center of the E-ring  40  substantially parallel to the upper surface of fuel tank  12 . Although  FIG. 2  and  FIG. 3  depict an E-ring  40  of the type generally embedded within a molded plastic tank, it will be appreciated that E-ring  40  can be mounted to the upper surface of the tank  12  as well. For attachment of E-rings  40  to metal tanks, it is known to utilize fasteners or welding to secure the E-ring  40  to the tank  12 , where it functions in substantially the same fashion as an E-ring  40  which is embedded in a molded plastic tank  12 . The E-ring  40  so configured and attached creates the basic point of attachment for the fuel transducer module  20 , when used in conjunction with an appropriate locking ring. 
         [0029]    A locking ring  60  of the type utilized in the present invention is depicted in  FIGS. 2 ,  4 ,  5  and in detail in  FIGS. 5A and 5B . The locking ring  60  comprises an annular body having a central aperture  64 . The outer circumference of the central aperture  64  is turned upward, creating a lip  66 . The lip  66  is provided with a plurality of plateaus  67  and ramp sections  65  which extend upward from the annular body portion at a height above the height of the remaining circumferential lip  66 . Also extending upward from the circumferential lip  66  is a plurality of feet  70   a - c , each comprising an ascender  68 , a toe portion  72 , a heel portion  71  and a slot  74 . The plurality of slots  74  associated with said plurality of ascenders  68  are open in the same circumferential orientation as shown in  FIG. 4 , to allow insertion of a cover element which will be described in detail herein. 
         [0030]    The body of the locking ring  60  is further provided with a plurality of arcurate openings  80 , each said arcurate opening  80  having a wide portion  82  and a narrow portion  84 . The width of the wide portion  82  of each said arcurate opening  80  corresponds to the width of the tab extension  50  of the E-ring tab  46 , so that the locking ring  60  may fit over the tab extensions  50  when the locking ring  60  wide portion  82  of the arcurate opening  80  is aligned with the tab extension  50  of the E-ring tabs  46 . As depicted in  FIG. 2 , once the locking ring  60  has been placed over the E-ring tabs  46 , it will rest substantially on the upper surface of the transducer  20  and of the fuel tank  12 . In this embodiment, a gasket  38 , preferably in the form of an O-ring, is placed between the annular body of the locking ring  60  and the upper surface of the fuel tank  12 , so as to be positioned between the bottom of the fuel transducer module  20  and the upper surface of the fuel tank  12 , thereby creating a fluid-tight seal between said fuel transducer module  20  and said fuel tank  12 . 
         [0031]    The fuel transducer module  20  body is formed with an annular lip  29  having a diameter larger than the diameter of the central aperture  64  of the locking ring  60 . Accordingly, placement of the locking ring  60  over the module  20 , and over the E-ring tabs  46  establishes the initial position for securing the fuel transducer module  20  to the upper surface of the fuel tank  12 . In this configuration, the locking ring  60  is ready for rotation in the direction R. 
         [0032]    From  FIGS. 2 ,  3  and  4 , it will be appreciated that the annular body of the locking ring  60 , adjacent to the narrow portion  84  of the arcurate openings  80 , is provided with a plurality of protrusions  86 . As the locking ring is rotated in direction R, the ascenders  48  of the tabs  46  of the E-ring  40  pass into the narrow portion  84  of the arcurate openings  80  of the locking ring, and at the same time tab extensions  50  engage the protrusions  86  of the locking ring  60 . The height of the ascenders  48  of the tabs  46  of the E-ring  40  is selected to result in engagement between the tab extensions  50  of the E-ring  40  with the protrusions  86  adjacent the arcurate openings  80  of the locking ring  60 . This engagement urges the locking ring  60  downward, toward the E-ring  40 , with the annular lip  29  of the fuel transducer module  20  captured under the annular body  62  of the locking ring  60 , and simultaneously compressing the gasket  38  between the annular lip of the fuel transducer module and the upper surface of the tank  12 . Detents  52  formed in the tab extensions  50  of the E-ring  40  frictionally engage the protrusions  86  adjacent to the narrow portions  84  of the arcurate openings  80 , preventing counter-rotation of the locking ring  60  in relation to the E-ring  40 . 
         [0033]    To facilitate the rotational engagement above described, the locking ring  60  is provided with a plurality of cutouts  76  around its circumference which are designed to engage with a cooperative installation tool (not shown). This tool is provided with a plurality of engaging fingers and a central socket of the type adapted to engage a square drive ratcheting wrench. By placement of the fingers of the tool in the cutouts  76  of the locking ring  60 , and by application of torque in the direction R, the locking ring  60  can be rotated conveniently into the locked configuration, after which the tool may be removed. 
         [0034]    At this stage in the installation process, the transducer module  20  is secured to the mounting surface of the fuel tank  12  by the locking ring  60  and its engagement with the E-ring  40 . With reference now to  FIGS. 2 ,  4 ,  5 ,  5 A and  5 B, securement of the protective cover  100  of the present invention will be fully understood. The protective cover  100  comprises a formed element having a body  102  and a plurality of legs  104 , each of said legs  104  having formed therein a foot  106 . In plan view, it will be appreciated that the legs  104  of the cover  100  are oriented as follows: two of the legs  104  are positioned substantially in diametric opposition, with a third leg  104  positioned approximately at an angle of approximately 60° (ø 1 ) to a first one of the legs  104 , and at an angle of approximately 120° (ø 2 ) to a second one of said first legs  104 . This configuration leaves a substantially semi-circular opening (ø 3 ) unimpeded, thereby allowing installation of the cover  100  even though the fuel transducer module  20  and its conduit and wiring already in place and connected. The cover  100  with its associated body  102  and legs  104 , provides protection to the fuel transducer module  20  in the event of a catastrophic impact to the fuel tank area surrounding the module. Each leg  104  of the cover is formed at its proximal end as a portion of the body  102 , and is bent substantially normal to the body  102 , thereby creating a descending leg  104  element to engage the locking ring  60 . At the distal end of each leg  104  is formed a foot  106  having a heel  108  and a guide  110  designed to engage the locking ring  60  in a manner to be described. Ridges  87  are formed in feet  106  to engage spring elements  79   a - c  as herein described. 
         [0035]    Each foot  70   a - c  of the locking ring  60  has a heel  71 , a toe  72  and a slot  74 . Affixed between the heel  71  and the toe  72  are clips  77   a - c , utilizing fasteners  69 , such as rivets. The clips  77   a - c  are formed of a resilient material, such as spring steel. The clips  77   a - c  each have a spring element  79   a - c  formed therein. One end of each spring element  79   a - c  is provided with a V-shaped detent  75 . Impressed within one surface of the V-shaped detent  75   c  is an impression  88 . This impression engages a gap  78  formed in foot  106 . At the distal end of each spring clip  77   a - c  an upward turned tang  73  is provided to allow engagement of a tool to lift the spring element  79   a , if necessary for removal of the cover. 
         [0036]    Complimentary to the locking ring feet  70   a - c  are cover element feet  106 , each of which is provided with a ridge  87  and a guide  110 . The guide  110  is oriented downwardly, and is configured to engage the outer circumference of the lip  66  of the locking ring  60 . The guides  110 , collectively, therefore, serve to guide and position the cover into juxtaposition with the locking ring  60 . Each foot  106  has a ridge  87  formed therein. As shown in  FIG. 5A , at least one of the foot  106  associated with at least one leg  104  of the cover  100  is provided with a gap  89  formed in ridge  87 . This gap  89  engages the impression  88  formed in the spring element  79   a  of the clip  77   a , effectively locking the spring element  79  into the upturned portion of the ridge  87 . 
         [0037]    To install the cover  100  in relation to the locking ring  60 , the cover  100  is placed on the locking ring  60  so that the undersides of the feet  106  rest on the upturned lip  66  of the annular body of the locking ring  60 , with the feet  106  of the cover adjacent to the feet  70  of the locking ring  60 . The cover is then rotated in direction R, bringing the feet  106  of the cover into the slots  74  of the locking ring feet  70 . This rotation also brings the feet  106  of the cover into engagement with the spring elements  79  of the clips  77 . Further rotation of the cover  100  in direction R brings the detents  75  of the spring elements  79  into engagement with ridges  87  on the cover feet  106 . Simultaneously, the guides  110  of the cover feet  106  serve to guide and position the cover  102  into alignment with the lip  66  of the locking ring  60 . Once fully engaged, the detent of the spring elements  79  locks the cover  100  into the desired positional relationship with the locking ring  60 . 
         [0038]    In one embodiment, the upper section of the protective cover is provided with a socket  120  configured to engage a typical square drive ratchet-type wrench to allow the cover  100  to be rotated into locked relationship with the locking ring  60  by providing the necessary mechanical advantage to impart the necessary torque to the cover  100 . 
         [0039]    By virtue of the angular relationship of the legs of the cover  100 , the cover  100  can be installed on and removed from the locking ring  60  without the necessity of disconnecting any of the electrical or fluid connections associated with the fuel transducer module  20 . 
         [0040]    The foregoing description of the preferred embodiment according to the present invention are provided for the purposes of illustration only, and not for purposes of limitation, the invention being defined by the claims: