AUTOMATIC SECURITY SYSTEM

• US 3,662,112 A
• Filed: 12/22/1969
• Issued: 05/09/1972
• Est. Priority Date: 12/22/1969
• Status: Expired due to Term

• Current Assignee: Stephen J. Martin
• Original Assignee: Stephen J. Martin
• Inventors: Martin, Stephen J.
• Primary Examiner(s): Claffy, Kathleen H.
• Assistant Examiner(s): Stewart, David L.
• Application Number:
  US04/887,250
• Time in Patent Office: 869 Days
• Field of Search: 179/5,5P,2A,18BD,18BE,18BF,1HF,1MN,1CN
• US Class Current: 379/40
• CPC Class Codes: H04M 11/045 using recorded signals, e.g. speech

Abstract

An automatic security system for use with public telephone facilities to centrally monitor various alarm events occurring at any one of a plurality of remote locations. The system includes a central monitoring complex having a number of operator stations connected to a local public telephone exchange, and a plurality of subscriber unit circuits, one for each remote location to be monitored, also coupled to public telephone exchange apparatus by conventional telephone lines. A number of sensing devices at each remote location operate in response to various alarm conditions to energize the subscriber unit causing automatic dialing of the central complex whereupon one of the operator stations will receive the call. The system includes solid-state circuitry for enabling effective operator station control of the various functions of the subscriber unit during an emergency by utilizing timed command tone signals.

Claims

1. An automatic security system for use with a telephone system comprising a subscriber unit connected by a first telephone line to the telephone system and including dialing means connected to said first telephone line for applying dialing pulses corresponding to a preselected telephone number to said first telephone line in response to the occurrence of a predetermined condition, communication circuit means connected to said first telephone line for transmitting and receiving audio communication signals along said first telephone line, and control circuit means connected to said dialing means, said communication circuit means and said first telephone line for selectively controlling said dialing means and said communication circuit means in response to command signals appearing on said first telephone line and having first and second predetermined envelope variations, respectively;

and an operator station including circuit means connecting said operator station to a second telephone line of the telephone system upon receipt of a ring signal from the telephone system in response to the dialing of said preselected number by said subscriber unit dialing means, and command signal generating means connected to said second telephone line by said circuit means and having first and second operative modes for selectively applying command signals having said first and second predetermined envelope variations to said second telephone line for transmission to said first telephone line by the telephone system whereby operation of said subscriber unit can be remotely controlled from said operator station.

2. The invention as recited in claim 1 wherein said dialing means includes pulsing means coupled to said first telephone line for electrically generating pulse signals corresponding to said preselected telephone number, and sensing means connected between said first telephone line and said pulsing means for energizing said pulsing means in response to a dial tone signal applied to said first line by the telephone system.

3. The invention as recited in claim 2 wherein said pulsing means includes dialing relay means connected to said first telephone line, and recording means connected to said dialing relay means and said sensing means for selectively operating said dialing relay means in accordance with preselected dialing signals generated by said recording means.

4. The invention as recited in claim 3 wherein said dialing means includes reset means connected to said recording means for de-energizing said pulsing means in response to a reset signal generated by said recording means and having a predetermined duration.

5. The invention as recited in claim 4 wherein said reset means includes a first reset timing means coupled To said recording means, and a second reset timing means connected to said first reset timing means and said pulsing means, each of said first and second reset timing means producing an output signal a predetermined time after an input signal is applied thereto, said predetermined time being less than said predetermined duration of said reset signal and greater than one-half said predetermined duration of said reset signal.

6. The invention as recited in claim 3 wherein said control circuit means includes tone receiver means coupled to said first telephone line for detecting said command signals on said first telephone line and producing output signals in response thereto having first and second time durations corresponding to said first and second predetermined envelope variations, respectively, of said command signals.

7. The invention as recited in claim 6 wherein said tone receiver means includes frequency selective filter means connected with said first telephone line, amplifier means connected with said filter means, envelope detecting means connected with said amplifier means, and waveshaping means connected with said envelope detecting means to produce said first and second time duration output signals in response to said first and second predetermined envelope variations of said command signals, respectively.

8. The invention as recited in claim 6 wherein said control means includes transmit-receive logic circuit means connected to said tone receiver means and said communication means for alternately enabling transmission and reception of audio communication signals by said communication means in response to output signals from said tone receiver means having said first time duration.

9. The invention as recited in claim 8 wherein said communication circuit means includes transducer means, transmit means coupled between said transducer means and said first telephone line for applying sounds picked-up by said transducer means to said first line, and receive means coupled between said transducer means and said first telephone line for audibly reproducing communication signals appearing on said first telephone line.

10. The invention as recited in claim 9 wherein said transmit-receive logic means includes flip-flop means coupled to said tone receiver means and having first and second alternately energized output terminals, and switching means coupled to said output terminals of said flip-flop means and said transmit and receive means of said communication circuit means for alternately energizing said transmit and receive means.

11. The invention as recited in claim 1 wherein said dialing means includes tape deck means storing dialing signals corresponding to said preselected telephone number, identification signals identifying the subscriber unit, and a hang-up signal.

12. The invention as recited in claim 11 wherein said tape deck means includes a tape head for picking up said dialing and identification signals from a magnetic tape, amplifier means connected to said tape head for amplifying said signals, and transformation circuit means connected between said amplifier means and said first telephone line for supplying said dialing and identification signals to said first telephone line.

13. The invention as recited in claim 12 wherein said dialing signals on said magnetic tape are tone burst signals, and said transformation circuit means includes a tone detector and a dialing relay connected to said tone detector and said first telephone line for momentarily opening said first telephone line in accordance with said tone burst dialing signals whereby dialing pulses corresponding to said preselected telephone number are applied to said telephone system.

14. The invention as recited in claim 13 wherein said identification signals on said magnetic tape are tone burst signals, and said dialing relay momentarily opens said first telephone line in accordance with said identification signals whereby a pulse train identifying said subscriber uNit is applied through said telephone system to said second telephone line.

15. The invention as recited in claim 14 wherein said hang-up signal on said magnetic tape is a tone signal having a predetermined time duration, and said dialing relay is responsive to said hang-up signal to open said first telephone line for a time interval corresponding to said predetermined time duration whereby said subscriber unit is disconnected from said telephone system.

16. The invention as recited in claim 15 wherein said dialing signal, said identification signals, and said hang-up signals are stored on said magnetic tape in sequence and are separated by blank intervals.

17. The invention as recited in claim 16 wherein said tape is looped upon itself such that said dialing signals, said identification signals and said hang-up signal are continuously repeated when said tape deck means is energized.

18. The invention as recited in claim 17 wherein said dialing means includes dial tone sensing means coupled to said first telephone line for energizing said tape deck in response to a dial tone signal on said first telephone line, and tape reset means responsive to said hang-up signal to de-energize said tape deck.

19. The invention as recited in claim 1 wherein said command signal generating means includes tone signal generating means, switch means connected to said tone signal generating means and said second telephone line, first command circuit means connected to said switch means for opening and closing said switch means to selectively apply said tone signals to said second telephone line in accordance with a first predetermined timing sequence when said command signal generating means is in said first operative mode, and second command circuit means connected to said switch means for opening and closing said switch means to selectively apply said tone signals to said second telephone line in accordance with a second predetermined timing sequence when said command signal generating means is in said second operative mode whereby command signals having said first and second predetermined envelope variations are applied to said second telephone line for transmission to said first telephone line.

20. The invention as recited in claim 19 wherein said first command circuit means includes first timing circuit means connected to said switch means for closing said switch means for a preset time interval.

21. The invention as recited in claim 20 wherein said timing circuit means includes latching means for conducting current to close said switch means when in a conductive state, and charging means coupled to said switch means and said latching means for extinguishing said latching means after said latching means has been in said conductive state for said preset time interval whereby said current flow to said switch means is established for said preset time interval.

22. The invention as recited in claim 21 wherein said second command circuit means includes contact means for selectively establishing a conductive path to said switch means for energizing said switch means, and indicator means coupled to said contact means for generating a visually perceptible signal after a particular time interval has elapsed subsequent to the establishment of said conductive path.

23. The invention as recited in claim 1 wherein said circuit means includes ringing signal detector means connected to said second telephone line, filter means connected to said ringing detector, and switching means connected to said filter means and said second telephone line for closing said second telephone line upon the application of a ringing signal to said second telephone line by the telephone system.

24. The invention as recited in claim 1 wherein said control circuit means includes dial inhibit means for disabling said dialing means in response to a command signal having an envelope variation which is periodic at a predetermined frequency.

25. The invention as recited in claim 24 wherein saiD dial inhibit means includes staircase generator means connected to said first telephone line for building up a voltage level at an output terminal in response to the receipt at said subscriber unit of a signal having at least said predetermined frequency, and first switch means connected with the output terminal of said staircase generator means and said dialing means for disabling said dialing means upon actuation in response to the voltage level of said staircase generator when said command signal having said periodic envelope variation is applied to said first telephone line.

26. The invention as recited in claim 25 wherein said dialing means includes dialing relay means for selectively opening and closing said first telephone line, and second switch means connected in series with said dialing relay means and further connected to said first switch means of said dial inhibit means for blocking current flow through said dialing relay means in response to the actuation of said first switch means.

27. The invention as recited in claim 26 wherein said command signal generating means includes tone generator means, and means selectively connecting said tone generator means to said second telephone line in accordance with a periodic time sequence signal having said predetermined frequency whereby command signals are applied to said second telephone line for transmission by the telephone system to said first telephone line for disabling said dialing means.

28. The invention as recited in claim 27 wherein said means selectively connecting said tone generator means to said second telephone line includes timing circuit means for generating a pulse train having a frequency which is twice said predetermined frequency, bistable means connected with said timing means for alternately switching between first and second states in response to each pulse of said timing circuit means pulse train, and contact means connected with said bistable means, said tone generator means and said second telephone line for connecting said tone generator means to said second telephone line when said bistable means is in said first state.

29. In an automatic security system including a plurality of subscriber units connected to a telephone system by a like plurality of subscriber telephone lines, an operator station comprising control switch means connected to said operator telephone line and having first and second operative positions, communication circuit means connected to said operator telephone line by said control switch means when said control switch means is in said first operative position for transmitting and receiving audio communication signals along said telephone line, tone generator means connected to said operator telephone line by said control switch means when said control switch means is in said second operative position, control circuit means connected to said control switch means for actuating said control switch means between said first and second operative positions in accordance with one of a plurality of preselected timing sequences whereby a like plurality of envelope modulated command signals are applied to said operator telephone line for transmission by the telephone system to said plurality of subscriber telephone lines, said control circuit means including timing means connected to said control switch means for momentarily actuating said control switch means between said first and second operative positions in accordance with a preselected timing sequence whereby a single pulse envelope modulated command signal is applied to said operator telephone line, and said timing means including controlled rectifier means connected to actuate said control switch means when in a conductive state, storage means connected with said controlled rectifier means for building up an electrical charge thereacross when said controlled rectifier is conductive, and transistor switch means connected between said storage means and said controlled rectifier meAns for renderring said controlled rectifier non-conductive when said electrical charge has reached a predetermined value.

30. The invention as recited in claim 29 wherein said transistor switch means comprises a unijunction transistor.

31. In an automatic security system including an operator station connected to a telephone system by an operator telephone line, a plurality of subscriber units each comprising dial tone sensing means connected to a subscriber telephone line for generating an output signal in response to the occurrence of first and second predetermined conditions, dialer means connected to said dial tone sensing means and said subscriber telephone line for applying dialing pulses corresponding to a preselected telephone number to said subscriber telephone line in response to said output signal from said dial tone sensing means, communication circuit means connected to said first telephone line and having a first mode for transmitting audio communication signals along said subscriber telephone line and a second mode for receiving audio communication signals appearing on said subscriber telephone line, and control circuit means connected to said dialer means, said communication means and said subscriber telephone line for disabling said dialer means in response to a command signal appearing on said subscriber telephone line and having a first predetermined envelope variation, and for alternately switching said communication circuit means between said first and second modes in response to a command signal appearing on said subscriber telephone line and having a second predetermined envelope variation.

32. The invention as recited in claim 31 wherein said communication circuit means includes transducer means, transmit means connected between said transducer means and said subscriber telephone line for applying audio signals picked up by said transducer means to said subscriber telephone line, receive means connected between said subscriber telephone line and said transducer means for audibly reproducing audio signals appearing on said subscriber telephone line, and bistable means connected to said transmit means, said receive means, and said control circuit means for alternately energizing said transmit and receive means in response to command signals having said second predetermined envelope variations whereby said communication circuit means is alternately switched between said first and second modes.

33. The invention as recited in claim 32 wherein said transmit means comprises a transmit audio amplifier for amplifying sounds picked up by said transducer means.

34. The invention as recited in claim 33 wherein said receive means includes a receive audio amplifier adapted to amplify audio sounds appearing on said telephone line for reproduction by said transducer means.

35. The invention as recited in claim 34 wherein said receive means further includes a tone filter connected between said receive audio amplifier and said subscriber telephone line for blocking passage of said command signals to said receive audio amplifier.

36. The invention as recited in claim 35 wherein said transducer means comprises a speaker-microphone.