TAMPER-PROOF SHOPLIFTING ALARM
First Claim
1. A shoplifting alarm comprising a housing, a plurality of circuit jacks mounted on a wall of said housing, a number of continuity loop segments attachable to said jacks for completing a continuity loop, an alarm circuit including alarm means and relay means, said alarm circuit being contained within said housing, means at the other end of said loops for securing said loops to articles of displayed merchandise, means for preventing substantial separation of said loop segments from said housing, said continuity loop and said relay means being so coupled to said alarm means as to delay energization thereof until a break occurs in one of said loop segments, said relay means including a controlled semiconductor having a triggering electrode, circuit means for connecting said semiconductor in series with said alarm means and a source of electric potential so that said alarm means are energized in the conductive state of said semiconductor, a triggering circuit for connecting said triggering electrode to said source, and a shunting continuity circuit including said continuity loop segments connected across at least a portion of said triggering circuit to prevent the application of source potential to said electrode.
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Accused Products
Abstract
I disclose a shoplifting alarm comprising a housing, a plurality of circuit jacks mounted on a wall of said housing, a number of loop segments attachable to said jacks for completing an alarm circuit including alarm means and being contained within said housing, means at the other end of each of said loops for securing said loops to articles of displayed merchandise, and means for preventing substantial separation of said loop segments from said housing.
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Citations
10 Claims
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1. A shoplifting alarm comprising a housing, a plurality of circuit jacks mounted on a wall of said housing, a number of continuity loop segments attachable to said jacks for completing a continuity loop, an alarm circuit including alarm means and relay means, said alarm circuit being contained within said housing, means at the other end of said loops for securing said loops to articles of displayed merchandise, means for preventing substantial separation of said loop segments from said housing, said continuity loop and said relay means being so coupled to said alarm means as to delay energization thereof until a break occurs in one of said loop segments, said relay means including a controlled semiconductor having a triggering electrode, circuit means for connecting said semiconductor in series with said alarm means and a source of electric potential so that said alarm means are energized in the conductive state of said semiconductor, a triggering circuit for connecting said triggering electrode to said source, and a shunting continuity circuit including said continuity loop segments connected across at least a portion of said triggering circuit to prevent the application of source potential to said electrode.
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2. The combination according to claim 1 wherein said triggering circuIt includes opposing resistance means coupled to said source and to said triggering electrode, and one of said resistance means being coupled in series with said continuity circuit.
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3. The combination according to claim 2 wherein each of said loop segments includes electrical shield means extending along the length thereof, and the other of said resistance means are connected between said shield means and a loop conductor of each loop segment so that severing or removing one of said loop conductors or shorting said shield means thereto will trigger said controlled semiconductor.
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4. The combination according to claim 1 wherein a normally open lock switch is coupled to said alarm circuit in parallel with said controlled semiconductor such that momentary closure of said normally open switch means resets said semiconductor to its nonconductive condition to deenergize said alarm means after said semiconductor has been triggered to energize said alarm means.
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5. A shoplifting alarm circuit including a controlled rectifier having a gating electrode, circuit means for connecting said rectifier in series with alarm means and a source of electric potential so that said alarm means are energized in the conductive state of said rectifier, a triggering circuit for connecting said gating electrode to said source, and a shunting continuity circuit connected across at least a portion of said triggering circuit to prevent the application of source potential to said gating electrode, said continuity circuit including a plurality of conductive loop segments shaped for securance to respective articles of merchandise, said alarm means being connected to the anode-cathode of said rectifier so that a break in one of said segments causes said rectifier and said source to energize said alarm means, said alarm means continuing to be energized through said anode-cathode although a circuit is reestablished through said one segment.
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6. The combination according to claim 5 wherein said alarm circuit includes resettable circuit means for actuating said alarm means upon interrupting the continuity of one of said continuity loop segments, electrically latchable means forming part of said relay means for continuing the energization of said alarm means upon restoration of said continuity, and resetting means for unlatching said latchable means.
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7. The combination according to claim 5 wherein said triggering circuit includes opposing resistance means coupled to said source and to said triggering electrode, and one of said resistance means being coupled in series with said continuity circuit.
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8. The combination according to claim 7 wherein said loop segment includes electrical shield means extending along the length thereof, and the other of said resistance means are connected between said shield means and a loop conductor of each loop segment so that severing or removing said loop conductor or shorting said shield means thereto will trigger said controlled semiconductor.
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9. The combination according to claim 5 wherein output terminal means are coupled to said circuit and are mounted in a wall of said housing for external access, said output terminal being connected to said circuit generally in parallel with said alarm means for the actuation of auxiliary external alarm means or recording apparatus connected to said terminal means upon energization of said alarm means.
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10. The combination according to claim 5 wherein a plurality of shorting jacks each including a shorting continuity segment are secured to said housing respectively adjacent each of said circuit jacks and engageable therewith for bypassing unused ones of said circuit jacks.
Specification