Vehicle security alarm

Security alarm apparatus for use on a motorized vehicle having an ignition switch and an ignition system, said security alarm apparatus comprising

• alarm emitting means;
• disturbance detection means for activating said alarm emitting means;
• means for disabling said alarm emitting means when said ignition switch is on, said disabling means having an input for being connected to said ignition switch;
• and
• means for unidirectional conduction of current between said ignition switch and said ignition system to energize said ignition system when said ignition switch is on, said unidirectional conduction means having a first lead connected to said input of said disabling means and a second lead for being connected to said ignition system so that said unidirectional conduction means is connected between said ignition switch and said ignition system.

Security alarm apparatus for use on a vehicle having an ignition system with an ignition switch, said security alarm apparatus comprising

• means for detecting at least a first disturbance and a second identical disturbance occurring to said vehicle;
• means for providing a first alarm response to said first disturbance and subsequently providing a second alarm response to said second identical disturbance, said second alarm response being qualitatively different from said first alarm response;
• means for disabling said apparatus from providing any alarm response when the ignition switch of the vehicle is on;
• and
• means for blocking said disabling means when the ignition system of the vehicle is energized but the ignition switch is off.

Security system for use in a motorized vehicle having an ignition system and a vehicle battery having a battery voltage, said security system comprising

• turn-on means for (A) permitting said battery voltage to be conducted to said ignition system when said turn-on means is on, (B) providing a modified battery voltage to a security voltage output of said turn-on means whenever said turn-on means is on, but (C) blocking the voltage at said security voltage output from being said modified battery voltage when said turn-on means is off and said ignition system is energized as by hotwiring to said ignition system, and (D) allowing the voltage at said security voltage output to become a second voltage condition distinct from said modified battery voltage when said turn-on means is off and said security voltage output is energized as by hotwiring;
• alarm emitting means capable of being caused to emit an alarm signal;
• sensing means for causing said alarm emitting means to emit an alarm signal when said vehicle is physically disturbed;
• and
• means for (1) disabling said alarm emitting means in response to said modified battery voltage whenever said modified battery voltage appears at said security voltage output and (2) whenever the voltage at said security voltage output becomes said second voltage condition, causing said alarm emitting means to emit an alarm signal.

Article for use in a motorized vehicle security system, said article comprising

• alarm emitting means capable of being caused to emit an alarm signal;
• sensing means for causing said alarm emitting means to emit an alarm signal when said vehicle is physically disturbed;
• means for disabling said alarm emitting means in response to a first voltage condition of an ignition switch conductor indicating that said motorized vehicle has its ignition switch on, thereby to keep said alarm emitting means from emitting an alarm signal even when said vehicle is physically disturbed;
• and
• means for responding to a second distinct nonzero voltage condition of said ignition switch conductor so as to block said second voltage condition from being received by said disabling means and so as to cause said alarm emitting means to emit an alarm signal,
• whereby hotwiring of said vehicle is made detectable.

Security system for use in a motorized vehicle having an ignition system and a vehicle battery having a battery voltage, said security system comprising

• turn-on means for (A) permitting said battery voltage to be conducted to said ignition system when said turn-on means is on, (B) providing a first voltage condition to a security voltage output of said turn-on means whenever said turn-on means is on, but (C) blocking the voltage at said security voltage output from being said first voltage condition when said turn-on means is off and said ignition system is energized as by hotwiring to said ignition system, and (D) allowing the voltage at said security voltage output to become a second voltage condition distinct from said first voltage condition when said turn-on means is off and hotwiring occurs;
• alarm emitting means capable of being caused to emit an alarm signal;
• and
• voltage-sensitive means for causing said alarm emitting means to emit an alarm signal in response to the voltage at said security voltage output only when the voltage at said security voltage output become said second voltage condition.