Abstract:
One embodiment of an anti-siphon fuel filler assembly includes a tube having a first end region adapted to be positioned in a fuel tank for allowing fuel to flow therethrough into said tank, the first end region including a first crimp and a second crimp, and a restriction structure positioned in the tube between the first crimp and the second crimp, the restriction structure including apertures sized for allowing fuel to flow therethrough while preventing the insertion of a siphon hose into the tank.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention is particularly intended for use on fuel tanks on commercial vehicles, although it may be used on any fuel tank connected to any type of engine. Fuel tanks typically include a filler tube inlet or opening through which fuel is filled into the fuel tank. On commercial vehicles the fuel tanks may be quite large. Due to high cost of fuel, these large fuel tanks may be susceptible to illegal siphoning of the fuel from the fuel tank.  
         [0002]     Siphoning of fuel from a fuel tank generally involves placing a hose through the filler tube inlet or opening and down into the fuel held within the fuel tank. A suction pressure is then applied to the opposite end of the hose such that fuel within the tank flows upwardly and out of the tank through the hose. Siphoning generally cannot be accomplished if the hose cannot be placed downwardly into the tank and into the fuel held within the tank.  
         [0003]     In order to prevent siphoning of fuel from fuel tanks, anti-siphon devices have been developed. One such anti-siphon device is described in U.S. Pat. No. 4,630,748, entitled Anti-Siphon Fuel Filler Assembly, wherein a tube is inserted into the tank inlet opening. A lower end of the tube is completely compressed together across the tube&#39;s diameter and then welded to form a lower restriction in the tube. Holes are cut or stamped in the lower region of the tube thereby allowing fuel to pass therethrough during filling of the fuel tank. The welded end of the tube generally prevents a hose from being placed downwardly into the fuel tank.  
         [0004]     The compressing and welding required for such prior art anti-siphon devices is labor intensive and requires certain manufacturing tools such as heavy duty compressing and welding machines. Accordingly, the prior art manufacturing process results in a device having a relatively large manufacturing cost.  
         [0005]     There is a need, therefore, for an anti-siphon fuel filler assembly that can be manufactured without expensive compressing and welding equipment, and which can be manufactured with reduced labor intensive manufacturing steps.  
       SUMMARY OF THE INVENTION  
       [0006]     One embodiment of an anti-siphon fuel filler assembly includes a tube having a first end region adapted to be positioned in a fuel tank for allowing fuel to flow therethrough into said tank, the first end region including a first crimp and a second crimp, and a restriction structure positioned in the tube between the first crimp and the second crimp, the restriction structure including apertures sized for allowing fuel to flow therethrough while preventing the insertion of a siphon hose into the tank. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]      FIG. 1  is an isometric view of one embodiment of an anti-siphon fuel filler assembly of the present invention.  
         [0008]      FIG. 2  is a cross-sectional side view of the anti-siphon fuel filler assembly taken along line  2 - 2  of  FIG. 1 , and shown installed on a fuel tank.  
         [0009]      FIG. 3  is an end view of the anti-siphon fuel filler assembly taken along line  3 - 3  of  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0010]      FIG. 1  is an isometric view of one embodiment of an anti-siphon fuel filler assembly of the present invention. Anti-siphon fuel filler assembly  10  in the embodiment shown comprises an elongate cylindrical body portion  12  including a first end region  14  and a second end region  16 . First end region  14  is adapted to be received within a fuel filler tube or opening of a fuel tank (see  FIG. 2 ) and second end region  16  is adapted to extend outwardly from or be positioned flush with a fuel tank opening (see  FIG. 2 ). Second end region  16  may include a lip  18  or another type of outwardly extending projection so as to secure the tube against movement through the opening and into the fuel tank (see  FIG. 2 ). Accordingly, lip  18  may have an outer diameter  20  that is greater than an outer diameter  22  of body portion  12  of assembly  10 . An O-ring  24  may be placed around an exterior  26  of body  12  and adjacent lip  18  to provide a seal between lip  18  and the opening of a fuel tank (see  FIG. 2 ) when the assembly is secured thereto.  
         [0011]     Body  12 , in a central region  28  thereof, may include a plurality of apertures  30  which may allow fluid and/or air to pass therethrough. Central region  28  may further include one or more retaining or deflection members, such as a tang  32 , extending outwardly from body  12 . Tang  32  generally extends outwardly from body  12  in an upper region of assembly  10 , toward second region  16  of body  12 , such that tang  32  acts to retain body  12  within a fuel tank once assembly  10  is inserted therein. In particular, tang  32  extends outwardly from body  12  to define a diameter  34  (see  FIG. 2 ) that may be larger than the diameter of an opening (see  FIG. 2 ) of a fuel tank such that assembly  10  is not easily removed from the opening in the direction through which the assembly was inserted. Accordingly, tang  32  and lip  18  together generally will retain assembly  10  in place on a fuel tank and against tampering or removal of the assembly from the fuel tank after installation thereof.  
         [0012]     Body  12  of assembly  10 , in the embodiment shown, is manufactured by the process of extrusion, such that body  12  may be seamless along its length  36 . Lip  18 , apertures  30  and tang  32  may be formed in body  12  after the extrusion process. Body  12  may be manufactured of aluminum but any durable material such as steel or heavy duty plastic may be utilized.  
         [0013]     Still referring to  FIG. 1 , first end region  14  of body  12  may include a first crimp  40  and a second crimp  42  which may secure an anti-siphon insert  44  within an interior  46  of body  12 . First crimp  40  may comprise a set of crimped regions, two of which,  40   a  and  40   b , are visible in this figure, that may each extend at least partially around a perimeter  48  of body  12 . In the embodiment shown, perimeter  48  defines a circumference of cylindrical body  12 . First crimps  40   a  and  40   b  may be indented or inwardly protruding regions of body  12  that extend partially into interior  46  of body  12  such that crimped regions  40   a  and  40   b  define an inner diameter (see  FIG. 3 ) that is smaller than an inner diameter (see  FIG. 3 ) of body  12 . In the embodiment shown, length  36  of body  12  may be in a range of approximately seven to twelve inches, and first crimps  40   a  and  40   b  may be positioned approximately {fraction (3/4)} of an inch from a lower end  50  of body  12 . Crimps  40   a  and  40   b  may extend into interior  46  of body  12  approximately {fraction (1/16)} of an inch. First crimp  40 , including  40   a  and  40   b , may be added to body  12  after extrusion of body  12 . Projection of first crimp  40  into interior  46  of body  12  only through a potion of interior  46 , such as only {fraction (1/16)} of an inch, generally requires less compression force than completely compressing body  12  across its diameter. Accordingly, the crimping process of the present invention requires reduced sized crimping machinery than the heavy duty compressing machinery of prior art devices. Accordingly, the present invention has reduced manufacturing costs when compared to prior art anti-siphon assemblies.  
         [0014]     Second crimp  42  may comprise a crimped region that extends completely around perimeter  48  at lower end  50  of body  12 . Second crimp  42  may be manufactured on body  12  after extrusion thereof. Second crimped region  42  may be an indentation or an inwardly protruding region of body  12  that defines an inner diameter (see  FIG. 3 ) that is smaller than an inner diameter (see  FIG. 3 ) of body  12 . Second crimp  42  may extend into interior  46  of body  12  approximately {fraction (1/8)} of an inch and may define an angle (see  FIG. 2 ) of approximately 45 degrees with respect to length  36  of body  12 . Accordingly, crimps  40  and  42  may retain insert  44  within interior  46  and between the first and second crimped regions  40  and  42 .  
         [0015]      FIG. 2  is a cross-sectional side view of the anti-siphon fuel filler assembly  10  taken along line  2 - 2  of  FIG. 1 , and shown installed on a fuel tank  52 . In particular, assembly  10  may be installed within a filler tube  54  that is installed in an opening  56  of fuel tank  52 . Filler tube  54  may be secured within opening  56  by any means, such as by welding, such that filler tube  54  generally is fixedly secured within opening  56 . Outer diameter  22  of anti-siphon assembly  10  may be only slightly smaller than an inner diameter  58  of filler tube  54  such that assembly  10  fits snugly therein. Filler tube  54  may have a length  60  that extends into an interior  62  of fuel tank  52  less than length  36  of anti-siphon assembly  10 . Moreover, length  60  of filler tube  54  is generally less than a length  61  of a portion of body  12  that extends from lip  18  to tang  32 . Accordingly, when assembly  10  is positioned within filler tube  54 , tangs  32  may be memory biased to extend outwardly into interior  62  of fuel tank  52  such that outer diameter  34  of tangs  32  is greater than inner diameter  58  of filler tube  54  thereby retaining anti-siphon assembly  10  in place within filler tube  54 .  
         [0016]     Still referring to  FIG. 2 , first crimp  40  is shown extending inwardly into interior  46  of body  12  a distance  64  of approximately {fraction (1/16)} inch. Crimp  42  is shown extending inwardly into interior  46  of body  12  a distance  66  of approximately {fraction (1/8)} inch and defining an angle  68  of approximately forty-five degrees. In other embodiments, crimps  40  and/or  42  may extend into interior  46  any distance less than the radius or midway point of a cross section of interior  46  such that crimps  40  and/or  42  do not meet one another. In other words, crimps  40  and/or  42  do not completely close off interior  46  of body  12  of assembly  10  but merely act as projections to secure an anti-siphon insert  44  therein.  
         [0017]      FIG. 3  is an end view of the anti-siphon fuel filler assembly  10  taken along line  3 - 3  of  FIG. 1 . Tang  32  and lip  18  are shown extending outwardly from body  12 . End  50  of body  12  is shown having second crimp  42  therein. Anti-siphon insert  44  is shown secured within interior  46  of body  12  between crimps  40  and  42 . Insert  44  may have a cross sectional shape which may be described as a snowflake or a hub-and-spoke arrangement. The hub-and-spoke shape of insert  44  may include a central hub  70  having a plurality of spokes  72  extending outwardly therefrom. Central hub  70  may define an aperture  74  positioned therein and spokes  72  may define a plurality of apertures  76  positioned therebetween. Apertures or openings  74  and  76  may sized so as to allow fuel and air to easily flow through insert  44 , but may be sized so as to prevent insertion of a siphon hose therethrough and into interior  62  of fuel tank  52 . The cylindrically symmetrical shape of insert  44  may add strength and stability to insert  44  such that insert  44  may not be easily broken or damaged by a vandal attempting to force a hose into tank  52  or a pry bar into filler assembly  10  to remove the insert therefrom. Of course, other shapes and designs of insert  44  may be utilized in other embodiments of the present invention. Insert  44  may be manufactured of aluminum but any durable material such as steel or heavy duty plastic may be utilized.  
         [0018]     Insert  44  typically may have a structure that is symmetrical about a central point of the insert, such as the snowflake or hub-and-spoke shape as shown, such that the insert may be easily manufactured by the process of extrusion. In particular, insert  44  may be extruded as a single, long piece of material and then cut across its cross-section and along its length to define individual inserts  44 . Insert  44  generally will have an outer diameter  78  that that is slightly smaller than the inner diameter  80  of body  12  such that insert  44  is snugly received therein. Moreover, the outer diameter  78  of insert  44  generally will be larger than the inner diameter  82  of body  12  at first crimp  40  and the inner diameter  84  of body  12  at second crimp  42 . Accordingly, insert  44  may retained within body  12  between crimps  40  and  42  such that the method of the present invention may include: providing body  12 , creating a first crimp, placing an insert  44  within body  12 , then creating a second crimp opposite the first insert to secure insert  44  within body  12  and between the two crimps. This extrusion and cutting process of insert  44 , and the process of placing the insert within body  12  between the creation of crimps  40  and  42 , may result in an anti-siphon device  10  that is relatively inexpensive to manufacture and assemble yet which provides high strength and reliability.  
         [0019]     In the above description numerous details have been set forth in order to provide a more through understanding of the present invention. It will be obvious, however, to one skilled in the art that the present invention may be practiced using other equivalent designs.