Intrusion alarm system
First Claim
1. An intrusion alarm system comprising:
- a sound pulse transmitter coupled to an entry means,said transmitter including triggering means for activating said transmitter to emit a high intensity sound pulse having a predetermined discriminating characteristic upon intrusion of said entry means,said transmitter comprising a photoflash unit and means activated by the radiant output of said photoflash unit for emitting said sound pulse,a sound detector spaced from and in sound communication with said transmitter,said detector including discriminating means selectively responsive to said predetermined characteristic of said sound pulse and substantially unresponsive to ambient sound conditions from other means,and means responsive to said detector for producing an alarm signal upon detection of said sound pulse.
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Accused Products
Abstract
An intrusion alarm system and method is provided which includes one or more sound pulse transmitters that are triggered upon the opening of an entryway, such as a door or window, to produce a high-intensity sound pulse having a decibel level above a predetermined minimum. For example, each transmitter may comprise a percussive photoflash unit in combination with a pyrotechnic device which responds to the radiant output of the fired photoflash unit to emit the intense sound pulse. A centralized detector responds to the sound pulse above a predetermined threshold level to produce an alarm signal. Preferably, the detector comprises an electroacoustical transducer arrangement which provides the dual functions of both sound pulse detection and generation of an audible alarm.
24 Citations
14 Claims
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1. An intrusion alarm system comprising:
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a sound pulse transmitter coupled to an entry means, said transmitter including triggering means for activating said transmitter to emit a high intensity sound pulse having a predetermined discriminating characteristic upon intrusion of said entry means, said transmitter comprising a photoflash unit and means activated by the radiant output of said photoflash unit for emitting said sound pulse, a sound detector spaced from and in sound communication with said transmitter, said detector including discriminating means selectively responsive to said predetermined characteristic of said sound pulse and substantially unresponsive to ambient sound conditions from other means, and means responsive to said detector for producing an alarm signal upon detection of said sound pulse. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
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Specification