Automatic fire extinguishing system

• US 4,821,805 A
• Filed: 06/28/1983
• Issued: 04/18/1989
• Est. Priority Date: 06/28/1982
• Status: Expired due to Fees

• Current Assignee: Hochiki Kabushiki Kaisha
• Original Assignee: Hochiki Kabushiki Kaisha
• Inventors: Nakayama, Hiroshi, Fukui, Hisao, Saito, Yoshifusa, Matsuoka, Naoya
• Primary Examiner(s): Kashnikow, Andres
• Assistant Examiner(s): Weldon, Kevin P.
• Application Number:
  US06/508,657
• Time in Patent Office: 2,121 Days
• Field of Search: 169/54, 169/61, 169/1, 250/554, 356/1, 356/4, 356/44, 356/152, 239/263.1
• US Class Current: 169/5
• CPC Class Codes: A62C 37/00 Control of fire-fighting equipment heat-sensitive devices G01K

Abstract

An automatic fire extinguishing system wherein at least two fire detecting sensors are provided. The sensors are disposed at a distance from each other and movable in the horizontal and vertical directions to scan the region to be protected for detecting the angles of a fire source in the horizontal and vertical directions. A distance to the fire source is obtained from the angles of the fire source detected by the respective sensors. A discharge nozzle is set based on the fire source position determined by the angles and the distance of the fire source.

Claims

1. An automatic fire extinguishing system comprising:

at least two fire detecting sensors disposed at a distance from each other, each being rotatably directable in the horizontal and vertical directions to scan a region to be protected;

driving means for controllably directing the scan of said fire detecting sensors in the horizontal and vertical directions;

first angular determining means operating to determine the vertical angle of a detected fire source as the lowermost angle at which the boundary of said fire source is detected by said sensors in the vertical scan thereof;

second angular determining means operating to determine the horizontal angle of a detected fire source as the average of the boundary of said fire source detected by said sensors in the horizontal scan thereof;

at least one discharge nozzle for fire extinguishing fluid rotatably directable in the horizontal and vertical directions;

computing means arranged to compute the horizontal distance from said discharge nozzle to said fire source based upon said vertical angle and said horizontal angle as determined by said first and second angular determining means;

driving means for controllably directing said discharge nozzle in the horizontal and vertical directions; and

control means for directing said nozzle driving means in the horizontal and vertical directions and operable under control of said computing means to direct said fire extinguishing fluid from said nozzle at said detected fire source in accordance with said vertical and horizontal angles thereof and said distance thereto.

2. An automatic fire extinguishing system as recited in claim 1 wherein said vertical angle of said discharge nozzle is directed upwardly from said determined vertical angle by an amount based upon said computed horizontal distance from said discharge nozzle to said fire source whereby said fire extinguishing fluid is properly directed at said fire source.

3. An automatic fire extinguishing system as recited in claim 1 wherein said fire detecting sensors employ pyroelectric transducers.

4. An automatic fire extinguishing system as recited in claim 1 further comprising means in said discharge nozzle controllable to vary the discharge area thereof, and control means for varying said discharge area in accordance with said computed distance to said fire.

5. An automatic fire extinguishing system as recited in claim 1 further comprising a fixed general monitoring fire sensor responsive to a fire within the region to be protected and operable to actuate operation of said fire extinguishing system in response to detection of a fire.

6. An automatic fire extinguishing system as recited in claim 1 wherein said driving means for directing said fire detecting sensors scans in the vertical direction upwardly from a low angle, and said vertical angle of a detected fire is determined at the lowermost angle at which the boundary of said fire source is detected.