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HANDS-FREE EMERGENCY TELEPHONE SYSTEM

  • US 3,800,089 A
  • Filed: 02/24/1972
  • Issued: 03/26/1974
  • Est. Priority Date: 02/24/1972
  • Status: Expired due to Term
First Claim
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1. A hands-free emergency telephone system comprising an outer housing forming an open-faced base for the support and protection of communication circuits, an outer cover plate fastened to said outer housing to form a protective cover over a part of the open face of said outer housing, a door hinged to said outer cover plate and positioned relative thereto to be operable to opened or closed positions through manual closure means, said door in its closed position forming a protective cover substantially over the remaining part of the open face of the outer housing, an inner housing formed by a multiple-faced mounting plate to which is attached an inner cover plate, said inner housing constituting a protective body containing means supporting communication circuits and components including electronic circuits, a microswitch, a microphone, a loudspeaker, and means connecting said microphone and said loudspeaker through said electronic circuits to first terminals of the microswitch, an opening in said inner housing providing access to said microswitch through said housing while preserving the protection to the microswitch afforded by said housing, said mounting plate supporting first electric terminal means connectable to lines terminating at a central office and to second terminals of said microswitch, means securing said inner housing within said outer housing and behind said outer cover plate and the door, said door covering access means to said microswitch and said door, when opened, permitting said microswitch to operate and complete electric connections between said microphone, said loudspeaker and said electronic circuits via the first and second terminals of the microswitch to the first electric terminal means, an opening through one face of said inner housing to permit acoustical coupling into the microphone, said outer housing substantially covering said one face to protect said opening and including space between said one face and said outer housing to enable acOustical coupling to be completed to said opening when the door is open, and a plurality of openings in said inner housing to permit acoustical coupling from the loudspeaker.

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