Electric burglar alarm system with exit and entry delay

Claim 1

AN ELECTRIC BURGLAR ALARM SYSTEM, SAID SYSTEM HAVING SERIALLY CONNECTED DETECTOR SWITCHES INCLUDING A DETECTOR SWITCH OPENED AND CLOSED UNDER CONTROL OF OPENING AND CLOSING OF AN ACCESS OPENING THROUGH WHICH ENTRY TO AND EXIT FROM THE CONFINES OF THE PREMISES GUARDED BY SAID SYSTEM IS AVAILABLE AND WHICH IS CLOSED EXCEPT WHEN SAID OPENING IS OPEN, A SOURCE OF CURRENT, CONTROL MEANS TOTALLY INACCESSIBLE FROM ANY LOCATION OUTSIDE THE PREMISES GUARDED BY SAID SYSTEM INCLUDING A MAIN SWITCH FOR STOPPING AND STARTING FLOW OF CURRENT FROM SAID SOURCE TO SAID DETECTOR SWITCH, A LOCK UP SWITCH OPERABLE BETWEEN A FIRST POSITION ENGAGING A FIRST CONTACT AND A SECOND POSITION ENGAGING A SECOND CONTACT AND BIASED TOWARD SAID SECOND POSITION, A FIRST RELAY, CONNECTIONS BETWEEN SAID RELAY AND SAID MAIN SWITCH TO ESTABLISH A CIRCUIT INCLUDING SAID DETECTOR SWITCH TO ENERGIZE SAID RELAY WHILE SAID DETECTOR SWITCH IS CLOSED AND SAID MAIN SWITCH IS IN "ON" POSITION, SAID RELAY BEING OPERATIVE WHILE ENERGIZED TO HOLD SAID LOCK UP SWITCH IN SAID FIRST POSITION, TIME DELAY MEANS OPERABLE IN RESPONSE TO ENERGIZATION OF SAID FIRST RELAY WHEN SAID RELAY IS INITIALLY ENERGIZED TO PREVENT DEENERGIZATION OF SAID FIRST RELAY PENDING EXPIRATION OF A FIRST TIME INTERVAL OF PREDETERMINED DURATION NOTWITHSTANDING OPENING OF SAID DETECTOR SWITCH DURING SUCH INTERVAL, A SECOND RELAY, CONNECTIONS BETWEEN SAID SECOND RELAY AND SAID SECOND CONTACT OF SAID LOCK UP SWITCH TO ESTABLISH A CIRCUIT TO ENERGIZE SAID SECOND RELAY UPON DEENERGIZATION OF SAID FIRST RELAY, TIME DELAY MEANS OPERABLE TO PREVENT ENERGIZATION OF SAID SECOND RELAY PENDING EXPIRATION OF A SECOND TIME INTERVAL OF PREDETERMINED DURATION NOTWITHSTANDING DEENERGIZATION OF SAID FIRST RELAY DURING SAID TIME INTERVAL, AN ELECTRICALLY OPERABLE ALARM AND A NORMALLY OPEN ALARM OPERATING SWITCH WHICH CLOSES UNDER CONTROL OF SAID RELAY WHEN SAID SECOND RELAY IS ENERGIZED.