rostad

Claim 1

AN AUTOMATIC TELEPHONIC ALARM SYSTEM WHICH TRANSMITS AN ALARM OVER TELEPHONE WIRES FROM A TRANSMITTING STATION HAVING A TELEPHONE CIRCUIT TO A RECEIVING STATION HAVING A TELEPHONE CIRCUIT, WHICH COMPRISES AN ALARM CIRCUIT AT THE TRANSMITTING STATION CONNECTED TO THE TELEPHONE CIRCUIT, A NORMALLY CLOSED PULSE SWITCH IN SAID ALARM CIRCUIT, A PULSE UNIT HAVING MEANS TO BRIEFLY AND REPEATEDLY OPEN SAID PULSE SWITCH TO PRODUCE PULSES WHICH REPRESENT THE TELEPHONE NUMBER OF THE RECEIVING STATION, AN ELECTROMAGNET, A NORMALLY OPEN AUTOMATICALLY OPERATED ALARM SWITCH CLOSABLE TO CAUSE SAID ELECTROMAGNET TO BECOME ENERGIZED, AN ARMATURE MOVABLE FROM A HOLD POSITION PREVENTING OPERATION OF SAID PULSE UNIT TO A RELEASE POSITION ENABLING OPERATION OF SAID PULSE UNIT BY SAID ENERGIZED ELECTROMAGNET, BIASING MEANS URGING SAID ARMATURE TO ITS HOLD POSITION WHEREBY DEENERGIZATION OF SAID ELECTROMAGNET RESULTS IN SAID ARMATURE BEING CONDITIONED TO ASSUME ITS HOLD POSITION, A SOURCE OF POWER OPERABLE UPON MOVEMENT OF SAID ARMATURE TO ITS RELEASE POSITION BY SAID ENERGIZED ELECTROMAGNET TO DRIVE SAID PULSE UNIT AND THEREBY PRODUCE PULSES WHICH REPRESENT THE TELEPHONE NUMBER OF THE RECEIVING STATION, AND ALARM MESSAGE GENERATING MEANS CONNECTED TO THE ALARM CIRCUIT AND OPERBLE BY SAID SOURCE OF POWER IN TIMED RELATIONSHIP WITH PRODUCING PULSES WHICH REPRESENT THE NUMBER OF THE RECEIVING STATION BY SAID PULSE UNIT TO TRANSMIT THE ALARM MESSAGE THROUGH SAID ALARM CIRCUIT AND THE TELEPHONE WIRES TO THE RECEIVING STATION.