Anti-theft device for motor vehicle fuel tank

Abstract

An anti-siphoning device for vehicle fuel tanks includes a barrier in the form of a honeycomb with hexagonal openings located between the fuel tank inlet and the tank itself. The device includes a retractable extension to accommodate a fuel refilling nozzle and openings to allow air in and out of the tank, which makes the refilling process easier.

1 . An anti-siphoning device for motor vehicle fuel tanks comprising a cylindrical housing securable within the fuel tank inlet; anchoring means for securing the housing within the inlet, a buffer to prevent insertion of a siphon tube element and an extensible neck element movable from a first position in which insertion of a fuel pump nozzle is prevented, to a second position in which the device has sufficient depth to receive the fuel pump nozzle for the purposes of filling the tank, the housing defining a passage between the tank inlet and the housing for free flow of air into and out of the tank during filling, the passage being in communication with the atmosphere by means of one or more air vents located in the housing. 
     
     
         2 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the buffer element and extensible neck element comprise a pair of concentric cylindrical elements locatable within the cylindrical housing. 
     
     
         3 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the buffer element comprises the innermost cylinder and includes at the upper end thereof a grid affixed thereto. 
     
     
         4 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which and the neck element is slidable between the housing and the buffer element. 
     
     
         5 . An anti-siphoning device for motor vehicle fuel tanks as claimed in any of  claim 1  in which the housing includes a pair of vertical slots including at the upper ends thereof a horizontal slot, in which guide formations on the perimeter of the neck element are slidable. 
     
     
         6 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 5  in which the guide formations permit vertical movement of the neck element as well as providing a means to retain the neck element in the extended position during filling. 
     
     
         7 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the housing includes a circumferential flange at the top end thereof with the air vents being located spaced apart around the collar. 
     
     
         8 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the bottom end of the cylindrical housing includes one or more formations for retaining the buffer and neck elements and preventing them from slipping into the tank. 
     
     
         9 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 8  in which the formation comprises an inwardly directed circumferential flange providing a ledge on which the bases of the neck and buffer elements rest. 
     
     
         10 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 8  in which the formation comprise welds. 
     
     
         11 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the neck element includes at the upper end thereof a collar about the opening thereof to engage the inner diameter of the housing, the collar being provided with a pull-ring or the like formation for lifting it into the extended position required for filling. 
     
     
         12 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 3  in which the grid is circular in shape and comprises a plurality of hexagonal apertures within the perimeter of the circle. 
     
     
         13 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the grid is circular in shape and comprises a plurality of square apertures within the perimeter of the circle. 
     
     
         14 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the cylindrical housing is securable within the tank inlet by means of a mounting plate which comprises a ring element including two or three spaced-apart lugs each adapted to receive a bolt 
     
     
         15 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which an adaptor is provided to secure the housing in the tank inlet. 
     
     
         16 . An anti-siphoning device for motor vehicle fuel tanks according to  claim 15  in which flanges engage cutout formations in the adaptor and the adaptor has either two or three cut outs. 
     
     
         17 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 16  in which, when the device is fitted, lugs are inserted into the cutouts in the adaptor and the ring element is rotated until the tugs abut against stopper elements at which point the bolts in the lugs are tightened and further bolts are inserted to prevent reverse rotation of the ring element. 
     
     
         18 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 7  in which the circumferential flange of the cylindrical housing engages by means of feet located on the underside of the flange and bolts extend through the circumferential flange of the cylindrical housing. 
     
     
         19 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 18  in which the position of the housing and neck and buffer elements is adjustable by tightening or loosening the bolts to draw them closer to the top of the tank inlet or urge them further away, respectively. 
     
     
         20 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 18  in which the dimensions of the feet differ to facilitate fitment in different vehicles. 
     
     
         21 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 1  in which the housing is provided with a series of spaced-apart spring clips, and the mounting plate is replaced by a circlip ring which fits underneath the circumferential flange of the cylindrical housing and engages the circular groove in the inlet, the spring clips being biased to engage the underside of the circlip to prevent removal. 
     
     
         22 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 15  in which the adaptor is internally screw-threaded to engage the correspondingly screw-threaded tank inlet/filler neck, the circumferential flange being held between the tank inlet and a lip formation in the underside of the adaptor. 
     
     
         23 . An anti-siphoning device for motor vehicle fuel tanks as claimed in  claim 22  in which the adaptor is secured with dowel pins which prevent the adaptor being unscrewed. 
     
     
         24 . (canceled)