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Earthquake alarm system

  • US 4,297,690 A
  • Filed: 03/05/1980
  • Issued: 10/27/1981
  • Est. Priority Date: 08/14/1978
  • Status: Expired due to Term
First Claim
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1. An earthquake alarm comprising:

  • a member having a referenced support at one end,a mass attached at the opposite end of said member a fixed distance from said referenced support,said mass being supported to have a preferred vertical position for a movement in a lateral direction only,adjustable mechanical detecting means for limiting the impulse lateral movement of said mass without changing the fixed distance of said mass from said referenced support,said mass being cylindrical and containing an opening at the lowermost end for accepting a vertically aligned adjustable probe attached to said mechanical detecting means and adapted to be selectively located in said opening without touching said mass, andelectrical means connecting said mechanical detecting means with an audio generating device for translating selected impulse movement of said mass into an audible signal.

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