(19)
(11)EP 2 899 517 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
27.07.2022 Bulletin 2022/30

(21)Application number: 15151942.8

(22)Date of filing:  21.01.2015
(51)International Patent Classification (IPC): 
G01J 5/00(2022.01)
(52)Cooperative Patent Classification (CPC):
G01J 5/0014; G01J 5/0803; G01J 5/04; G01J 5/54; G08B 29/145; G08B 17/113; G01J 5/0018; G08B 17/12; G01J 5/52

(54)

Apparatuses, systems and methods for self-testing optical fire detectors

Vorrichtungen, Systeme und Verfahren zur Selbstprüfung optischer Rauchdetektoren

Appareils, systèmes et procédés d'autotest de détecteurs d'incendie optique


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 27.01.2014 US 201414164409

(43)Date of publication of application:
29.07.2015 Bulletin 2015/31

(73)Proprietor: Kidde Technologies, Inc.
Wilson, NC 27896 (US)

(72)Inventors:
  • Bell, Ken
    Raleigh, NC 27610 (US)
  • Thebert, Robert
    Raleigh, NC 27613-7271 (US)

(74)Representative: Dehns 
St. Bride's House 10 Salisbury Square
London EC4Y 8JD
London EC4Y 8JD (GB)


(56)References cited: : 
EP-A2- 1 039 426
US-A1- 2003 058 114
US-A1- 2013 286 391
US-A- 5 914 489
US-A1- 2013 228 692
US-B1- 8 564 879
  
      
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    FIELD



    [0001] The present disclosure generally relates to apparatuses, systems, and methods for testing optical flame detectors ("OFDs") and, more specifically, to OFDs comprising self-test systems.

    BACKGROUND



    [0002] Testing and calibration of infrared OFDs in the mid-infrared wavelengths relies on heat sources (e.g., heater elements, black bodies or flaming fires). For various reasons (e.g., speed, convenience, accuracy, precision, and expense), none of these solutions are particularly commercially satisfactory. In addition, none of the solutions are particularly suitable for field testing of an infrared flame detection system.

    [0003] A prior art smoke detector is disclosed in US 2013/0286391. A prior art multispectral infrared simulation target array is disclosed in US 8,564,879. A prior art fire detection system is disclosed in US 2003/0058114.

    SUMMARY



    [0004] From one aspect, the present invention provides an optical flame detector in accordance with claim 1.

    [0005] From another aspect, the present invention provides a self-testing fire suppression system in accordance with claim 4.

    [0006] These features and elements as well as the operation of the disclosed embodiments will become more apparent in light of the following description and accompanying drawings.

    BRIEF DESCRIPTION OF THE DRAWINGS



    [0007] The subject matter of the present disclosure is particularly pointed out and distinctly claimed in the concluding portion of the specification. A more complete understanding of the present disclosure, however, may best be obtained by referring to the detailed description and claims when considered in connection with the drawing figures, wherein like numerals denote like elements.

    FIG. 1 illustrates a cross-sectional view of a first self-testing OFD, in accordance with the disclosure; and

    FIG. 2 illustrates a cross-sectional view of a second self-testing OFD, in accordance with various embodiments.


    DETAILED DESCRIPTION



    [0008] The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the inventions, it should be understood that other embodiments may be realized and that logical, chemical and mechanical changes may be made without departing from the scope of the inventions. Thus, the detailed description herein is presented for purposes of illustration only and not of limitation. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Also, any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option. Additionally, any reference to without contact (or similar phrases) may also include reduced contact or minimal contact.

    [0009] Microelectromechanical systems ("MEMS") based infrared sources may enable construction of more accurate and precise test equipment to test and/or verify operation of flame detection sensors and/or systems. Moreover, this test equipment may reduce and/or eliminate the need for other types of heat sources (e.g., heater elements, black bodies, flaming fires, and/or the like). In various embodiments, MEMS systems may be micromachines, micro systems technology and/or the like that have a typical size from approximately 20 micrometers to approximately 1 millimeter.

    [0010] In various embodiments, a testing system comprising one or more MEMS infrared emitters may be integrally installed in and used to test infrared OFDs. In this regard, the OFD may comprise multiple MEMS infrared emitters with each MEMS infrared emitter emitting a particular wavelength of infrared. For example, the OFD may comprise a first MEMS infrared emitter emitting mid infrared and a second MEMS infrared emitter emitting near infrared. Accordingly, the OFD may be capable of testing multi-channel infrared detectors. In this regard, the OFDs may detect infrared at one wavelength and/or various wavelengths. The infrared spectrum is typically regarded as electromagnetic radiation of wavelengths 700 nm to 1 mm. Mid infrared may be regarded as between 3 µm to 8 µm. Near infrared may be regarded as between 0.75 µm to 1.4 µm. Short wavelength infrared may be regarded as between 1.4 µm to 3 µm. Wavelengths typically emitted by a MEMS infrared emitters may include, for example, approximately 0.9 µm, approximately 2.8 µm and/or approximately 4.3 µm.

    [0011] In various embodiments, a MEMS infrared emitter may be a film-like device (e.g., a film resistor). In this regard, the MEMS infrared emitter may have characteristics similar to a resistor in a circuit. The MEMS infrared emitter may have nearly zero mass. Nearly zero mass may allow for rapid heating and cooling of the MEMS infrared emitter (e.g., heating in milliseconds). In various embodiments, the MEMS infrared source may behave like a heater. In this regard, the MEMS infrared source may sweep through a plurality of infrared wavelengths (e.g., wavelengths from approximately 0.75 µm to 8 µm). In various embodiments, a MEMS infrared emitter may have a longer life than typical heating sources used for sensor testing.

    [0012] In various embodiments and with reference to FIG. 1, an OFD 100 may comprise a detector 110 (e.g., a sensor) and an infrared source 120. Detector 110 and infrared source 120 may be housed within body 130. Body 130 includes an opening including a window 140. Window 140 optically and/or operatively couples detector 110 and the environment surrounding OFD 100. OFD 100 may also be operatively and/or electrical coupled to a fire suppression system 150. Fire suppression system 150 may include a fire suppression system (e.g., a sprinkler system), a controller, a power source, a data collection system, a notification system and/or the like. Moreover, fire suppression system 150 may comprise any suitable microprocessor, circuitry, a hardware-software system, and/or the like configured to control self-testing operations and /or emissions from infrared source 120.

    [0013] Infrared source 120 may comprise a single MEMS infrared emitter or an array of multiple MEMS infrared emitters and light emitting diodes ("LED") emitters that are capable of emitting visible light and/or IR. In this regard, the array may comprise a plurality of MEMS infrared emitters. The array may also comprise one or more infrared emitters and one or more LED emitters. The LED emitters are configured to produce a first set of wavelengths (e.g., shorter wavelengths such as, for example, 0.9 µm). The one or more infrared emitters are configured to produce a second set of wavelengths (e.g., longer wavelengths, such as, for example, 2.8 µm and 4.3 µm). Moreover, the LED emitters and infrared emitters are configured to operate at different times.

    [0014] In various embodiments, infrared source 120 may be installed at a specified distance and orientation relative to detector 110. In this regard, infrared source 120 may be an appropriate distance from detector 110 to insure proper self-testing and/or infrared emission detection. Moreover, infrared source 120 may be configured to directly illuminate detector 110.

    [0015] In various embodiments, OFD 100 and/or fire suppression system 150 may comprise a user input 152. User input 152 may be operatively coupled to and/or in electronic communication with infrared source 120 and/or fire suppression system 150. In this regard, the user input may be capable of communicating an input to perform and/or initiate a self-test to at least one of infrared source 120 and/or fire suppression system 150. In various embodiments, user input 152 may comprise a switch. In various embodiments, user input 152 may comprise an electronic interface configured to receive input from another electronic device. For example, user input 152 may comprise a Universal Serial Bus ("USB") interface. In such embodiments, the USB interface of user input 152 may receive logical commands from another electronic device such as a cell phone, smart phone, tablet, personal digital assistant, laptop computer, desktop computer, and combinations of the same.

    [0016] In various embodiments, window 140 is operatively coupled and/or formed in body 130 of OFD 100. Window 140 allows detector 110 to monitor and/or evaluate and environment within which OFD 100 is installed. Window 140 may comprise one or more coatings, screens, lenses and/or the like. In this regard, window 140 is capable of reflecting emission 122 from infrared source 120 to detector 110. In this regard, infrared source 120 may be positioned so as not to obstruct the field of monitoring of detector 110, but may still be capable of creating emission 122 to conduct a self-test of detector 110.

    [0017] In various embodiments, window 140 may be glass, sapphire, a crystal structure and/or the like. Window 140 may comprise a transparent structure and/or film configured to modify and/or condition emissions that interact with window 140. Window 140 is configured to filter emissions from infrared source 120. In this regard, detector 110 is exposed to and/or detects particular wavelengths based on and/or in response to the filtering.

    [0018] In various embodiments and with reference to FIG. 2, OFD 200 comprises a plurality of detectors 210 (shown as 210A and 210B in FIG. 2). The plurality of detectors 210 are housed in body 230. OFD also comprises a plurality of infrared sources 220 (shown as 220A and 220B in FIG. 2).

    [0019] In various embodiments, OFD 200 comprises a first infrared source 220A and a second infrared source 220B. In this regard, OFD 200 may be capable of testing for multiple wavelengths. First infrared source 220A is capable of creating a first emission 222A having a first wavelength. First emission 222A is directed to first detector 210A and is reflected from first window 240A. First infrared source is capable of creating a second emission 224A having the first wavelength. Second emission 224A is directed to second detector 210B. First emission 222A and second emission 224A may be substantially similar.

    [0020] In various embodiments, second infrared source 220B is capable of creating a third emission 222B and a fourth emission 224B. Third emission 222B and fourth emission 224B has a second wavelength. Third emission 222B is reflected from second window 240B and directed to second detector 210B. Fourth emission 224B is directed to first detector 210A. Third emission 222B and fourth emission 224B may be substantially similar.

    [0021] In various embodiments, user input 252 may be in electronic communication with fire suppression system 250 and/or first infrared source 220A and second infrared source 220B. In this regard, an input at user input 252 may cause first emission 222A, second emission 224A, third emission 222B, and/or fourth emission 224B.

    [0022] In various embodiments, the plurality of infrared sources 220 may be selectable. For example and in response to an input at user input 252, at least one of first infrared source 220A and second infrared source 220B may be activated and may produce infrared emissions having wavelengths of, for example, approximately 0.9 µm, approximately 2.8 µm and/or approximately 4.3 µm. The plurality of infrared sources 220 are caused to emit infrared individually and/or in a preselected pattern.

    [0023] Infrared sources 220 are MEMS-based high output infrared sources and LED based near infrared sources 220. Infrared sources 220 may be configured in an array. In this regard, infrared sources 220 may be arranged to produce emissions that simulate a fire. Infrared sources 220 may have rapid response rates.

    [0024] In an arrangement not claimed, OFD 200 may comprise a single infrared source 220. In this regard, infrared source 220 may be capable a creating a plurality of emissions having various wavelengths including, for example, first emission 222A, second emission 224A, third emission 222B, and/or fourth emission 224B.

    [0025] In various embodiments, field testing of OFD 200 in operating environment may be challenging to conventional systems. If OFD 200 should be tested using a flicker effect for activation and space around installed OFD 200 is limited, testing may be challenging and/or impossible with conventional testing systems and procedures. Conventional testing systems and procedures that are bright enough to activate OFD 200 may be of significant size. Moreover, the flicker function may require a mechanical chopper to introduce the time varying output. In this regard, the constraints created by limited space in environment where OFD 200 is installed to make integral testing capabilities more efficient and desirable.

    [0026] In various embodiments, infrared source 220 may be a MEMS-based high output infrared source that has reproducible output in the infrared spectrum of emissions having wavelengths of approximately 1 µm to approximately 20 µm. In OFD 200, infrared source 220 may be capable of producing full output infrared emissions in tens of milliseconds.

    [0027] In various embodiments, OFD 200 may comprise infrared source 220 mounted within the casing of OFD 200 such that, if activated by a self-test command, detector 210 of OFD 200 may detect the emission. In response to, successful detection of infrared source 220, electrical amplification circuitry and alarm logic of OFD 200 may generate a signal and/or indicate to flame suppression system 250 to indicate that the self-test was successful. A successful self-test of OFD 200 may indicate that detector 210 is capable of detecting emissions and that the controller unit and/or alarm output circuitry of OFD 200 is operational.

    [0028] In various embodiments, one or more infrared sources and detectors may be mounted on separate boards and/or in separate locations. Moreover, these separate infrared sources and/or detectors may be optically coupled. In this regard, the infrared source (e.g., infrared source 120 as shown in FIG. 1) may be in a "direct line of sight" with a detector (e.g., detector 110 as shown in FIG. 1).

    [0029] Benefits, other advantages, and solutions to problems have been described herein with regard to specific embodiments. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and/or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in a practical system. However, the benefits, advantages, solutions to problems, and any elements that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as critical, required, or essential features or elements of the inventions. The scope of the inventions is accordingly to be limited by nothing other than the appended claims, in which reference to an element in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more." Moreover, where a phrase similar to "at least one of A, B, or C" is used in the claims, it is intended that the phrase be interpreted to mean that A alone may be present in an embodiment, B alone may be present in an embodiment, C alone may be present in an embodiment, or that any combination of the elements A, B and C may be present in a single embodiment; for example, A and B, A and C, B and C, or A and B and C.

    [0030] Systems, methods and apparatus are provided herein. In the detailed description herein, references to "one embodiment", "an embodiment", "various embodiments", etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described. After reading the description, it will be apparent to one skilled in the relevant art(s) how to implement the disclosure in alternative embodiments.


    Claims

    1. An optical flame detector (200) comprising:

    a body (230);

    a first infrared source (220A) housed within the body (230) configured to produce a first emission (222A, 224A), wherein the first infrared source (220A) is a MEMS device;

    a second infrared source (220B) housed within the body (230) configured to produce a second emission (222B, 224B), wherein the second infrared source (220B) is an LED emitter, wherein the first emission (222A, 224A) has a first wavelength and the second emission (222B, 224A, 224B) has a second wavelength, and the first infrared source (220A) and the second infrared source (220B) are configured to operate at different times.

    a first window (240A) coupled to the body (230) configured to filter and reflect the first emission (222A) from the first infrared source (220A) and the second emission (224B) from the second infrared source (220B);

    a second window (240B) coupled to the body (230) configured to filter and reflect the first emission (224A) from the first infrared source (220A) and the second emission (222B) from the second infrared source (220B);

    a first detector (210A) housed within the body (230) configured to monitor an environment through the first window (240A) and to receive the first emission (222A) from the first infrared source (220A) reflected by the first window (240A) and to receive the second emission (224B) from the second infrared source (240B) reflected by the first window (240A); and

    a second detector (210B) housed within the body (230) configured to monitor the environment through the second window (240B) and to receive the first emission (224A) from the first infrared source (220B) reflected by the second window (240B) and to receive the second emission (222B) from the second infrared source (220B) reflected by the second window (240B).


     
    2. The optical flame detector of claim 1, wherein the first infrared source (220A) is capable of producing a plurality of emissions (222A, 222B, 224A, 224B) having wavelengths of approximately 1 µm to approximately 20 µm.
     
    3. The optical flame detector of any preceding claim, wherein the infrared source (220) is collocated on the same surface as the detector (210).
     
    4. A self-testing fire suppression system (250) comprising the optical flame detector (200) of any preceding claim.
     


    Ansprüche

    1. Optischer Flammendetektor (200), umfassend:

    ein Gehäuse (230);

    eine erste Infrarotquelle (220A), die in dem Gehäuse (230) untergebracht und dazu konfiguriert ist, eine erste Emission (222A, 224A) zu erzeugen, wobei die erste Infrarotquelle (220A) eine MEMS-Vorrichtung ist;

    eine zweite Infrarotquelle (220B), die in dem Gehäuse (230) untergebracht und dazu konfiguriert ist, eine zweite Emission (222B, 224B) zu erzeugen, wobei die zweite Infrarotquelle (220B) ein LED-Emitter ist, wobei die erste Emission (222A, 224A) eine erste Wellenlänge aufweist und die zweite Emission (222B, 224A, 224B) eine zweite Wellenlänge aufweist, und die erste Infrarotquelle (220A) und die zweite Infrarotquelle (220B) für einen Betrieb zu unterschiedlichen Zeiten konfiguriert sind.

    ein erstes Fenster (240A), das an das Gehäuse (230) gekoppelt und dazu konfiguriert ist, die erste Emission (222A) von der ersten Infrarotquelle (220A) und die zweite Emission (224B) von der zweiten Infrarotquelle (220B) zu filtern und zu reflektieren;

    ein zweites Fenster (240B), das an das Gehäuse (230) gekoppelt und dazu konfiguriert ist, die erste Emission (224A) von der ersten Infrarotquelle (220A) und die zweite Emission (222B) von der zweiten Infrarotquelle (220B) zu filtern und zu reflektieren;

    einen ersten Detektor (210A), der in dem Gehäuse (230) untergebracht und dazu konfiguriert ist, eine Umgebung durch das erste Fenster (240A) zu überwachen und die durch das erste Fenster (240A) reflektierte erste Emission (222A) von der ersten Infrarotquelle (220A) aufzunehmen und die durch das erste Fenster (240A) reflektierte zweite Emission (224B) von der zweiten Infrarotquelle (240B) aufzunehmen; und

    einen zweiten Detektor (210B), der in dem Gehäuse (230) untergebracht und dazu konfiguriert ist, eine Umgebung durch das zweite Fenster (240B) zu überwachen und die durch das zweite Fenster (240B) reflektierte erste Emission (224A) von der ersten Infrarotquelle (220B) aufzunehmen und die durch das zweite Fenster (240B) reflektierte zweite Emission (222B) von der zweiten Infrarotquelle (220B) aufzunehmen.


     
    2. Optischer Flammendetektor nach Anspruch 1, wobei die erste Infrarotquelle (220A) dazu in der Lage ist, eine Vielzahl von Emissionen (222A, 222B, 224A, 224B), die Wellenlängen von etwa 1 µm bis 20 µm aufweisen, zu erzeugen.
     
    3. Optischer Flammendetektor nach einem vorangehenden Anspruch, wobei die Infrarotquelle (220) an derselben Fläche wie der Detektor (210) angeordnet ist.
     
    4. Selbstprüfendes Brandunterdrückungssystem (250), umfassend einen optischen Flammendetektor (200) nach einem vorangehenden Anspruch.
     


    Revendications

    1. Détecteur optique de flamme (200) comprenant :

    un corps (230) ;

    une première source infrarouge (220A) logée à l'intérieur du corps (230) conçue pour produire une première émission (222A, 224A), dans lequel la première source infrarouge (220A) est un dispositif MEMS ;

    une seconde source infrarouge (220B) logée à l'intérieur du corps (230) conçue pour produire une seconde émission (222B, 224B), dans lequel la seconde source infrarouge (220B) est un émetteur DEL, dans lequel la première émission (222A, 224A) a une première longueur d'onde et la seconde émission (222B, 224A, 224B) a une seconde longueur d'onde, et la première source infrarouge (220A) et la seconde source infrarouge (220B) sont conçues pour fonctionner à des moments différents.

    une première fenêtre (240A) couplée au corps (230) conçue pour filtrer et réfléchir la première émission (222A) de la première source infrarouge (220A) et la seconde émission (224B) de la seconde source infrarouge (220B) ;

    une seconde fenêtre (240B) couplée au corps (230) conçue pour filtrer et réfléchir la première émission (224A) de la première source infrarouge (220A) et la seconde émission (222B) de la seconde source infrarouge (220B) ;

    un premier détecteur (210A) logé à l'intérieur du corps (230) conçu pour surveiller un environnement à travers la première fenêtre (240A) et pour recevoir la première émission (222A) de la première source infrarouge (220A) réfléchie par la première fenêtre (240A) et pour recevoir la seconde émission (224B) de la seconde source infrarouge (240B) réfléchie par la première fenêtre (240A) ; et

    un second détecteur (210B) logé à l'intérieur du corps (230) conçu pour surveiller l'environnement à travers la seconde fenêtre (240B) et pour recevoir la première émission (224A) de la première source infrarouge (220B) réfléchie par la seconde fenêtre (240B) et pour recevoir la seconde émission (222B) de la seconde source infrarouge (220B) réfléchie par la seconde fenêtre (240B).


     
    2. Détecteur optique de flamme selon la revendication 1, dans lequel la première source infrarouge (220A) est capable de produire une pluralité d'émissions (222A, 222B, 224A, 224B) ayant des longueurs d'onde d'environ 1 µm à environ 20 µm.
     
    3. Détecteur optique de flamme selon une quelconque revendication précédente, dans lequel la source infrarouge (220) est colocalisée sur la même surface que le détecteur (210).
     
    4. Système d'extinction d'incendie à autotest (250) comprenant le détecteur optique de flamme (200) selon une quelconque revendication précédente.
     




    Drawing








    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description