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Staff-location and signalling system for use in mines

  • US 4,495,495 A
  • Filed: 01/18/1982
  • Issued: 01/22/1985
  • Est. Priority Date: 01/20/1981
  • Status: Expired due to Fees
First Claim
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1. A staff-location and signalling system for operation in a mine, comprising:

  • at least one base station adapted to be located in the mine area and comprising a transmitter for transmitting radio signals;

    at least one first signal receiver;

    at least one secondary wave-guide adapted to extend through at least part of the mine area for transmitting radio signals between said at least one base station and said first signal receiver at a distance therefrom;

    a miner'"'"'s lamp adapted to be carried by a person in the mine area;

    the first signal received being associated with said lamp and adapted to respond to coded radio signals transmitted by said at least one base station; and

    a normally-closed working-current circuit connecting said associated miner'"'"'s lamp to a source of working current;

    said at least one first signal receiver being adapted to open and close said circuit so that the miner'"'"'s lamp can be switched off and on in accordance with said coded radio signals.

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