COMBINATION FIRE AND BURGLAR ALARM SYSTEM

• US 3,603,973 A
• Filed: 04/11/1968
• Issued: 09/07/1971
• Est. Priority Date: 04/11/1968
• Status: Expired due to Term

• Current Assignee: Howard O. Hough
• Original Assignee: Howard O. Hough
• Inventors: Hough, Howard O.
• Primary Examiner(s): Caldwell, John W.
• Assistant Examiner(s): Partridge, Scott F.
• Application Number:
  US04/720,587
• Time in Patent Office: 1,244 Days
• Field of Search: 340/333,409,227,276,228,420,258C 307/66
• US Class Current: 340/506
• CPC Class Codes: G08B 19/00 Alarms responsive to two or more different undesired or abnormal conditions, e.g. burglary and fire, abnormal temperature and abnormal rate of flow

Abstract

A fire and burglar alarm system for providing automatic detection of a fire or burglary having active and passive components which are capable of operating at very low power levels continuously until the components are called upon to indicate a fire or burglary. The system is provided with alternate sources of power to insure the reliability of operation. Supervisory circuitry is provided for giving visual indication that all sensors and circuitry are in proper operating conditions. Annunciator circuitry is also provided to give visual indication of exact location or zone of conflagration.

Claims

1. A fire alarm system for indicating a fire in a given area comprising a fire sensor, means for identification of fire area or zone, means for giving a first audio alarm responsive to said fire sensor, said fire sensing responsive alarm means being connected in circuit with said fire sensor, a first power supply for operating said fire alarm system connected to said fire sensor and a second power supply, means responsive to a failure of said first power supply for connecting said second power supply to said fire sensor, and means for preventing the false activation of said first means for giving an audio alarm due to electrical transients generated during the operation of said fire sensor means connected to said means for giving a first audio alarm, thereby preventing the activation of said audio alarm by electrical radiations generated by bolts of lightning and other stray electrical noise, a trouble alarm and means responsive to the failure of said first power supply and to malfunction of said second power supply for actuating said trouble alarm connected to said trouble alarm, means for sensing a burglary connected in series circuit with said fire sensor but capable of activating only the trouble alarm but incapable of inadvertant operation of the fire alarm circuit, and said burglary sensing means causing said series circuit to be broken when a burglary is detected, thereby causing said trouble alarm to activate and said fire alarm remaining in a nonactivated condition.

2. A fire alarm system as defined in claim 1, but further characterized by having visual means for indicating the operability of said first power supply connected in parallel with said first current source.

3. A fire alarm system as defined in claim 1, but further characterized by having a third power supply, said means responsive to a failure of said first power supply for connecting said second power supply to said fire sensor connecting said third power supply to said trouble alarm means.

4. A fire alarm system as defined in claim 3, wherein said first power supply comprises:

a transformer having a secondary winding, means for rectifying an AC current connected to said secondary winding and means for regulating the output voltage of said current rectifying means connected to said current rectifying means.

5. A fire alarm system as defined in claim 1, wherein said first power supply comprises:

a transformer having a secondary winding, means for rectifying an AC currenT connected to said secondary winding and means for regulating the output voltage of said current rectifying means connected to said current rectifying means.

6. A fire alarm as defined in claim 1, but further characterized by having annunciator means for indicating the location of the fire on the premises to be protected.