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Tamper-proof security alarm system

  • US 4,167,733 A
  • Filed: 01/10/1977
  • Issued: 09/11/1979
  • Est. Priority Date: 01/10/1977
  • Status: Expired due to Term
First Claim
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1. A device of the kind described, comprising in combination:

  • (a) a casing,(b) an electrical, gravity-responsive switch construction disposed wholly in the casing, said switch construction being open-circuited when motionless and in a given predetermined position, and being closed-circuited when it experiences either acceleration or arcuate movement, or both,(c) suspension means for suspending the switch construction from a pivotal point above the same for free swinging movement, said suspension means enabling the switch construction, under the force exerted thereon by gravity, to occupy an infinitely large number of different arcuate positions within and with respect to the casing,(d) manually releasable clamping means acting on said suspension means, for normally maintaining the switch construction in any given one of said infinitely large number of arcuate positions with respect to the casing, thereby to normally maintain said switch construction open-circuited except when experiencing said acceleration or arcuate movement or both,(e) a second electrical switch construction connected in parallel with the first-mentioned switch construction,(f) means responsive to operation of said manually releasable means, for closing the circuit of said second electrical switch construction,(g) an electro-responsive device, and(h) circuit means connected with both said switch constructions, for controlling said electro-responsive device.

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