Anti-theft device for vehicles

Claim 1

An anti-theft device in combination with a motor vehicle having a combustion engine, a tank containing fuel for said engine, a fuel line connecting said engine to said tank, means for drawing fuel from said tank and delivering the fuel to said engine to cause the operation of the engine, a fuel gauge associated with said tank for indicating the amount of fuel therein, an electrical power source, said power source connected by an ignition switch to said fuel gauge, said fuel gauge having an indicator means shiftable between full and empty positions for indicating the amount of fuel in said tank when said gauge is energized by said power source, said ignition switch having an on position causing said fuel gauge to be energized and an off position, said anti-theft device comprising a valve connected to said fuel line between said engine and fuel tank, said valve having a normal closed position isolating said tank from said engine, a switch member carried by said vehicle in a hidden location having first and second operative positions, said valve being operatively connected to said power source through said ignition switch and switch member, said valve being shifted into an open position when said ignition switch is shifted into its on position and said member is in its first position, said valve being in its closed position when either said ignition switch is shifted into its off position or said switch member is in its second position, and means associating said switch member with said fuel gauge for causing said indicator means of the fuel gauge to be located in its empty position when said switch member is in its second position whereby said fuel tank will be isolated from said engine and said fuel gauge will indicate empty regardless of the position of said ignition switch.