Multiple sensor interconnected alarm system responsive to different variables

• US 4,401,976 A
• Filed: 01/14/1981
• Issued: 08/30/1983
• Est. Priority Date: 01/16/1980
• Status: Expired due to Fees

• Current Assignee: Hans-Gunther Stadelmayr
• Original Assignee: Hans-Gunther Stadelmayr
• Inventors: Stadelmayr, Hans-Gunther
• Primary Examiner(s): Swann, III, Glen R.
• Application Number:
  US06/225,000
• Time in Patent Office: 958 Days
• Field of Search: 340/522, 340/541, 340/508, 340/554, 367/94
• US Class Current: 340/522
• CPC Class Codes: G08B 13/00 Burglar, theft or intruder alarms
• CPC Class Codes: G08B 13/19 using infrared-radiation detection systems G08B13/194 takes precedence
• CPC Class Codes: G08B 29/046 prevention of tampering with detection circuits
• CPC Class Codes: G08B 29/16 Security signalling or alarm systems, e.g. redundant systems
• CPC Class Codes: G08B 29/183 Single detectors using dual technologies G08B13/1672, G08B13/2448, G08B13/2494 take precedence

Abstract

An alarm, safeguarding and monitoring system for a room zone includes a plurality of sensors disposed at different positions and responsive to different physical phenomena, such as an ultrasonic sensor, an infrared sensor and a microwave sensor. The sensor outputs are individually coupled to majority decision, central processing unit and alarm generator circuits by a plurality of redundant signal links to minimize malfunction in the event of disruption or tampering.

Claims

1. Alarm, safeguarding and monitoring system having a plurality of sensors in one room, comprising:

at least three sensors which respond to physical phenomena of a different nature which always occur in every alarm event, said sensors being disposed to cover the same monitoring zone, and means responsive to output signals from said sensors for generating an alarm signal according to the majority principle.

2. Alarm, safeguarding and monitoring system according to claim 1, wherein three sensors respond to three different physical phenomena.

3. Alarm, safeguarding and monitoring system, according to claim 2, wherein at least two of the sensors work according to the Doppler principle and are disposed angularly with respect to one another.

4. Alarm, safeguarding and monitoring system according to claim 3, wherein the sensors working according to the Doppler principle are disposed orthogonally with respect to one another.

5. Alarm, safeguarding and monitoring system according to claim 3, wherein the outputs of the individual sensors working according to the Doppler principle are fed to an OR circuit, whose output is coupled to said alarm signal generating means.

6. Alarm, safeguarding and monitoring system according to claim 3, wherein different types of sensors are integrated in one casing.

7. Alarm, safeguarding and monitoring system according to claim 3, wherein individual signal connections between different functional groups have at least three signal paths which are independent of one another and whose outputs are processed by a majority logic circuit.

8. Alarm, safeguarding and monitoring system according to claim 3, wherein an activate/deactivate circuit has at least two signal paths which are independent of one another.

9. Alarm, safeguarding and monitoring system according to claim 3, wherein an on/off circuit and peripheral monitoring and actuating units are not connected via any system wiring, so that even if these units are located this does not lead to the location or destruction of a central processing unit.

10. Alarm, safeguarding and monitoring system according to claim 9, wherein coding of the central processing unit ensues via an external unit which has no direct connecting path to the central processing unit.

11. Alarm, safeguarding and monitoring system according to claim 10, wherein in the case of permanent connection leads to on/off switches, monitoring and actuating units, a galvanic interruption is inserted into the connection leads.

12. Alarm, safeguarding and monitoring system according to claim 11, wherein the galvanic interruption is effected via a relay circuit.

13. Alarm, safeguarding and monitoring system according to claim 2, wherein two ultrasonic sensors and one infrared sensor are provided.

14. Alarm, safeguarding and monitoring system according to claim 2, wherein two microwave sensors and one infrared sensor are provided.

15. Alarm, safeguarding and monitoring system according to claim 2, wherein two sensor pairs disposed angularly to one another, each pair comprising a microwave sensor and an ultrasonic sensor, and one infrared sensor are provided.

16. Alarm, safeguarding and monitoring system according to claim 15, wherein the infrared sensor is disposed separate from the sensor pairs.