Stop auto theft

Claim 1

An anti-theft device in combination with motor vehicle having an internal combustion engine and an ignition system, said device comprising: a transformer having a primary winding and a stepped-up secondary winding; a distributor connected to said secondary winding; a starter-connected ignition switch for starting the engine, said switch having a first accessible terminal and a second substantially non-accessible terminal; a voltage source connected to said first accessible terminal of said ignition switch; voltage-dropping means for dropping the voltage of said voltage source, said voltage-dropping means having a third substantially non-accessible terminal connected to said second terminal, and a fourth accessible terminal; a circuit breaker connected to said fourth accessible terminal of ignition switch and set to trip at a predetermined current; a relay having a coil connected to, and energizable by said ignition switch through said circuit breaker, and at least a pair of contacts closable by operating said ignition switch, one of said contacts being connected to said voltage source, said coil being designed to burn out at a current just exceeding said predetermined current, said ignition switch, said voltage dropping means, said circuit breaker and said relay being connected in series across said voltage source; and periodically openable contact means actuable by closure of said pair of contacts, the latter, said contact means, and said voltage source being connected in series with said primary winding, whereby said circuit breaker trips upon a thief shorting said accessible terminals and the relay coil burns out upon the thief shorting said circuit breaker comma thus preventing the closure of said pair of contacts and actuation of said periodically openable contact means.