Self-checking device of flame detector

Abstract

The utility model discloses a self-checking device of a flame detector, which comprises an infrared sensor, an ultraviolet sensor, an infrared light source and an ultraviolet light source which are connected with a microprocessor, and the infrared sensor and the ultraviolet sensor are respectively connected with the infrared light source and the ultraviolet light source for self-checking and are close to a glass window in front of the sensors; the infrared sensor and the circuit thereof are used for receiving optical radiation energy generated by flames and converting the optical radiation energy into voltage signals; the ultraviolet sensor and the circuit thereof are used for receiving optical radiation energy generated by flames, when the flames exist, the ultraviolet sensor is changed into a conducting state from a high-resistance state, and a microprocessor of the ultraviolet sensor is further connected with an optical radar circuit for shielding detection within an effective distance and a defrosting circuit. The self-checking device of the flame detector realizes self-checking of a light path of the sensor, improves the accuracy of flame detection, and reduces the false alarm rate.

Description

TECHNICAL FIELD

[0001] The utility model relates to the equipment of fire safety detection especially a self -checking device of flame detector. BACKGROUND

[0002] As the key equipment of fire safety monitoring, the core technology of flame detector lies in detecting the specific wavelength light generated by flame to distinguish flame from interference, so as to identify whether there is flame. Once detecting flame, the detector will rapidly send signal to fire alarm system or fire extinguishing system, and start corresponding emergency operation, such as issuing alarm, starting water spray fire extinguishing system or closing related equipment, so as to effectively curb the spread of fire and protect personnel and property safety.

[0003] Generally, the infrared sensor of flame detector is used to detect the carbon dioxide radiation spectrum characteristics generated by carbonaceous substance combustion for flame detection, but it is easy to be disturbed by heat source or light pollution and other interference sources, causing false alarm. There is a glass structure in front of the sensor on the product structure, because the industrial environment used by the self -checking device of flame detector is relatively complex, the condition is relatively bad, the glass is often polluted or there may be objects blocking in front of the detector, resulting in that the detector cannot work normally. In addition, the detector needs to be checked by artificial inspection frequently to confirm whether the function of the detector is normal, which not only consumes time and effort, but also is not suitable for personnel to enter in some dangerous places, so that the stability and reliability of the product cannot be guaranteed. SUMMARY

[0004] The technical problem to be solved by the utility model is to provide a self -checking device of flame detector, realize sensor light path self -checking, improve the accuracy of flame detection and reduce the false alarm rate.

[0005] In order to solve the above technical problem, the utility model provides a self -checking device of flame detector, including infrared sensor, ultraviolet sensor, infrared light source and ultraviolet light source connected with microprocessor, the infrared sensor and ultraviolet sensor are connected with infrared light source and ultraviolet light source for self -checking respectively and are close to the glass window in front of the sensor, the infrared sensor and its circuit are used to receive the light radiation energy generated by flame, and convert it into voltage signal, the ultraviolet sensor and its circuit are used to receive the light radiation energy generated by flame, when there is flame, the ultraviolet sensor changes from high resistance state to conduction state, the microprocessor is still connected with optical radar circuit and defrosting circuit for obstruction detection within effective distance.

[0006] Further, the circuit of infrared sensor includes: power supply filter capacitor C18 and capacitor C21 connected with infrared sensor S1, the two ends of capacitor C18 are connected with monitoring circuit for real -time monitoring and band -pass filter and signal amplification circuit for outputting voltage signal.

[0007] Further, the real-time monitoring circuit comprises: resistors R22 and R26 connected in series and then connected to both ends of capacitor C18, resistors R25 and capacitor C22 connected in series and then connected in parallel with resistor R26; the band-pass filter and signal amplification circuit comprises: operational amplifier U4, whose same direction end is connected to capacitor C17, resistor R20 and one end of capacitor C16, whose opposite direction end is connected to one end of resistor R24 and capacitor C23, and whose output end is connected to one end of resistor R23, and the other end of resistor R23 is connected in series with capacitor C20 and grounded.

[0008] Further, the circuit of the ultraviolet sensor comprises: a voltage circuit required for generating ultraviolet light, a signal expansion signal circuit, an ultraviolet circuit monitoring circuit and a low-pass filter and signal expansion circuit connected with the ultraviolet sensor D5.

[0009] Further, the voltage circuit comprises: transformer T1, one set of pins of which is connected to diode D1 and capacitor C2, and the other set of pins of which is connected to power supply end through capacitor C1, diode D2 and capacitor C5, and diode D2 and one end of triode Q1 are connected; the signal expansion signal circuit comprises: chip U2A and one end of resistor R2, capacitor C6, capacitor C7 and resistor R1 connected with the chip U2A, and the other end of capacitor C7 and resistor R1 is connected with amplifier U1B, and amplifier U1B, resistor R4 and resistor R8 are connected with each other as the expansion signal of UV_T signal for controlling triode Q1 to be turned on, and the ultraviolet circuit monitoring circuit comprises: one end of ultraviolet sensor D5 and resistor R10 connected with the ultraviolet sensor D5, the other end of resistor R10 connected with one end of resistor R12 and capacitor C10, and the other end of capacitor C10 connected with U3.

[0010] Further, the low-pass filter and signal expansion circuit comprises: one end of resistor R19 and resistor R16 connected with ultraviolet sensor D5, the other end of resistor R16 connected with operational amplifier U1A, resistor R16 further connected in parallel with capacitor C13 and capacitor C14, and chip U2B connected with operational amplifier U1A through resistor R17, and chip U2B further connected with capacitor C15, resistor R13 and capacitor C11.

[0011] Further, the circuit of the infrared light source comprises: triode Q2 and resistor R22 connected in sequence with one end of infrared light source D4 and then grounded, and the other end connected with operational amplifier U5, and operational amplifier U5 further connected in parallel with resistor R21 and capacitor C19 and in series with resistor R19, and operational amplifier U5 and triode Q2 connected with each other through resistor R20.

[0012] Further, the circuit of the ultraviolet light source comprises: one end of ultraviolet light source D5 connected with the collector of triode Q3, the emitter of triode Q3 connected with resistor R26 and grounded, and the base of the emitter of triode Q3 connected in sequence with resistor R25 and operational amplifier U6, and operational amplifier U6 further connected with resistor R23, resistor R24 and capacitor C20.

[0013] Further, the optical radar circuit comprises the chip U8 and resistors R44, R45, R46, capacitors C23 and C24 connected with the chip U8.

[0014] Further, the defrosting circuit is further provided, and the heating resistor R27-resistor R35, resistor R37, resistor R40, capacitor C21, operational amplifier U7, resistor R39, triode Q4 and resistor R42 are connected with each other to provide a starting control signal for the heating resistor R27-resistor R35.

[0015] The technical effect of the utility model lies in that the self-checking device of the flame detector realizes sensor light path self-checking, solves the disadvantages of manual inspection, improves product stability and reliability. The self-checking device of the flame detector is often interfered by interference sources and misreported. The problem that the self-checking device of the flame detector needs to be tested by artificial excitation source frequently is solved. The problem that the detector cannot alarm after window frosting and dewing in low-temperature environment is solved. The problem that the detector cannot alarm after glass pollution or detection window is blocked is solved. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is the structural schematic view of the self-checking device of the utility model flame detector;

[0017] Figure 2 It is the circuit structure schematic view of the infrared sensor of the self-checking device of the utility model flame detector;

[0018] Figure 3 It is the circuit structure schematic view of the ultraviolet sensor of the self-checking device of the utility model flame detector;

[0019] Figure 4 It is the infrared light source structure schematic view of the self-checking device of the utility model flame detector;

[0020] Figure 5 It is the ultraviolet light source structure schematic view of the self-checking device of the utility model flame detector;

[0021] Figure 6 It is the optical radar circuit structure schematic view of the self-checking device of the utility model flame detector;

[0022] Figure 7 It is the structure schematic view of the initial frost circuit of the self-checking device of the utility model flame detector. DETAILED DESCRIPTION

[0023] The utility model will be further described below in combination with the drawings and specific embodiments, so that the person skilled in the art can better understand the utility model and can be implemented, but the embodiment is not as the limitation of the utility model.

[0024] The technical solutions in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.

[0025] In the description of the utility model, it needs to be explained that the orientation or position relationship indicated by the terms "upper", "lower", "inner", "outer", "top / bottom end" and the like is the orientation or position relationship shown based on the drawings, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the utility model. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0026] In the description of the utility model, it needs to be explained that, unless otherwise explicitly specified and limited, the terms "mounting", "provided with", "sleeved / connected", "connected" and the like should be understood broadly, for example, "connected" can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be electrically connected; can be directly connected, can be indirectly connected through an intermediate medium, and can be the communication inside two elements. For the person skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0027] As Figure 1 The utility model discloses a self-checking device of flame detector, including infrared sensor, ultraviolet sensor, infrared light source and ultraviolet light source that microprocessor connects, infrared light source and ultraviolet light source are close to the glass window before the sensor and carry out light path self-checking to infrared sensor and ultraviolet sensor;The circuit of infrared sensor is used for receiving the light radiation energy generated by flame, and converts it into voltage signal;The circuit of ultraviolet sensor is used for receiving the light radiation energy generated by flame, when there is flame, ultraviolet tube changes from high resistance state to conducting state, and its microprocessor is also connected with optical radar circuit and defrosting circuit.

[0028] As Figure 2As shown, the infrared sensor circuit includes: the power supply filter capacitor C18 and capacitor C21 connected with infrared sensor S1, the two ends of capacitor C18 are connected with real-time monitoring circuit and the band-pass filter and signal amplification circuit outputting voltage signal. The real-time monitoring circuit includes: the series connection of resistor R22 and resistor R26 connected to the two ends of capacitor C18, and the parallel connection of resistor R25 and capacitor C22 with resistor R26; the band-pass filter and signal amplification circuit includes: operational amplifier U4, whose same direction end is connected with capacitor C17, resistor R20 and one end of capacitor C16, whose opposite phase end is connected with one end of resistor R24 and capacitor C23, and one end of resistor R23 connected with the output end of operational amplifier U4, and the other end of resistor R23 connected with capacitor C20 and grounded.

[0029] Wherein, S1 is an infrared sensor for receiving light radiation energy generated by flame and converting it into voltage signal. Capacitor C18 and capacitor C21 are filter capacitors of power supply for S1. Resistor R22, resistor R26, resistor R25 and capacitor C22 are monitoring circuit of infrared sensor circuit, which monitors whether the sensor is normal in real time. C17, resistor R20, capacitor C16, resistor R21, resistor R24, capacitor C23, U4, resistor R23 and capacitor C20 constitute the band-pass filter and signal amplification circuit of the output voltage signal of infrared sensor.

[0030] The infrared sensor circuit for detecting carbon-containing substance combustion wave band, detecting hydrogen combustion wave band and flame reference judgment is completely consistent, only the wave band of the sensor is different. By comparing different infrared wave band characteristics, such as frequency characteristics and energy ratio, flame and interference can be identified, and the accuracy of flame detection can be improved.

[0031] As shown in Figure 3 The circuit of the ultraviolet sensor includes: voltage circuit, signal expansion signal circuit, ultraviolet circuit monitoring circuit and low-pass filter and signal expansion circuit required for generating ultraviolet light during work and connected with ultraviolet sensor D5. The voltage circuit includes: transformer T1, one group of pins of which are connected with diode D1 and capacitor C2, and the other group of pins of which are connected with capacitor C1, diode D2 and capacitor C5 to the power supply end, and the one end of diode D2 and triode Q1 are connected, which together generate the voltage required for generating ultraviolet light during work;

[0032] The signal expansion signal circuit includes: chip U2A and the one end of resistor R2, capacitor C6, capacitor C7 and resistor R1 connected with U2A, the other end of capacitor C7 and resistor R1 connected with amplifier U1B, and the mutual connection of amplifier U1B, resistor R4 and resistor R8 as the expansion signal of UV_T signal for controlling the conduction of triode Q1. The signal expansion signal circuit is the expansion signal of UV_T signal for controlling the conduction of Q1.

[0033] The ultraviolet circuit monitoring circuit includes: the ultraviolet sensor D5 and one end of the resistance R10 connected therewith, the other end of the resistance R10 connected with the resistance R12 and one end of the capacitor C10, and the other end of the capacitor C10 connected with U3. The monitoring circuit monitors whether the ultraviolet circuit is normal in real time.

[0034] The low-pass filter and signal widening circuit includes: the resistance R19 and one end of the resistance R16 connected with the ultraviolet sensor D5, the other end of the resistance R16 connected with the operational amplifier U1A, the resistance R16 further connected in parallel with the capacitor C13 and the capacitor C14, the chip U2B connected with the operational amplifier U1A through the resistance R17, and the chip U2B further connected with the capacitor C15, the resistance R13 and the capacitor C11.

[0035] As shown in Figure 4 , the infrared light source circuit includes: the triode Q2 and the resistance R22 connected in sequence with one end of the infrared light source D4 and grounded, and the other end connected with the operational amplifier U5, the operational amplifier U5 further connected in parallel with the resistance R21 and the capacitor C19 and in series with the resistance R19, and the operational amplifier U5 and the triode Q2 connected through the resistance R20. The infrared light source circuit constitutes an infrared light source control signal, and the frequency or voltage of the IR_LA1 signal can be adjusted to control the light emitting amount of the infrared light source. After the infrared light source emits light, the infrared light source is reflected through the glass window and the space to the infrared sensor to realize self-checking of the infrared sensor. Several infrared sensors can share the infrared light source, or each infrared sensor can be provided with an infrared light source. The advantage of using this method is that the reflector structure of the outer shell of the detector does not need to be increased, which is conducive to increasing the detection angle of the detector.

[0036] As shown in Figure 5 , the ultraviolet light source circuit includes: the collector of the triode Q3 connected with the external light source D5, the emitter of the triode Q3 connected with the resistance R26 and grounded, the base of the emitter of the triode Q3 connected in sequence with the resistance R25 and the operational amplifier U6, and the operational amplifier U6 further connected with the resistance R23, the resistance R24 and the capacitor C20. The ultraviolet light source circuit constitutes an ultraviolet light source control signal, and the frequency or voltage of the UV_LAMP signal can be adjusted to control the light emitting amount of the ultraviolet light source.

[0037] The ultraviolet light source is placed below the ultraviolet light, and after emitting light, it can directly excite the ultraviolet light to act, thereby realizing self-checking of the ultraviolet sensor.

[0038] As shown in Figure 6As shown, the utility model detector still is equipped with optical radar circuit, including chip U8 and resistance R44, resistance R45, resistance R46, electric capacity C23 and electric capacity C24 connected with it. U8 is optical radar sensor, integrates pixel array and control calculation unit in it, need not additional optical element support. Can provide accurate ranging information to different reflectivity material, color and texture object. Sensor has ambient light suppression performance, can carry out ranging under outdoor sunlight.

[0039] In product application, cooperate special structure to complete effective ranging, realize glass pollution and front effective distance inside shielding detection, can send out prompt in time.

[0040] As Figure 7 As shown, the utility model detector still is equipped with defrosting circuit, including resistance heating resistance R27~resistance R35 network, resistance R37, resistance R40, electric capacity C21, operational amplifier U7, resistance R39, triode Q4 and resistance R42 are connected as control signal of heating resistance R27~resistance R35 start.

[0041] When flame detector runs in the environment of lower temperature, often has glass frost or fog situation. The detector can start defrosting resistance heating when temperature is lower than starting setting threshold value, and turn off defrosting resistance heating when temperature is higher than stopping setting threshold value. Resistance R27~R35 are heating resistance network, can be placed close to glass window on the layout, reach faster heating effect. Resistance R37, resistance R40, electric capacity C21, resistance U7, resistance R39, triode Q4, resistance R42 are control signal of heating resistance start. Heat_EN can be high and low level, also can be pulsating signal, can realize different heating resistance effect. Resistance R38, resistance R43 and heating resistance network realize circuit monitoring function when not starting heating function together. Resistance R41 is NTC resistance, realizes environmental temperature detection function with resistance R36, provides temperature parameter for starting and closing defrosting function.

[0042] The utility model detector still is equipped with alarm output circuit.

[0043] The above-mentioned embodiment is only for fully illustrating the preferred embodiment of the utility model, and the protection scope of the utility model is not limited to this. The equivalent replacement or transformation of the technical personnel in the technical field on the basis of the utility model is all within the protection scope of the utility model. The protection scope of the utility model is accurate with the patent claim.

Claims

1. A self-checking device for a flame detector comprising a microprocessor connected to an infrared sensor, an ultraviolet sensor, an infrared light source and an ultraviolet light source, characterized in that, The infrared sensor and the ultraviolet sensor are respectively connected with infrared light source and ultraviolet light source for self-checking and are arranged close to the glass window in front of the sensor; the infrared sensor and its circuit are used for receiving light radiation energy generated by the flame and converting it into voltage signal; the ultraviolet sensor and its circuit are used for receiving light radiation energy generated by the flame, and when there is flame, the ultraviolet sensor changes from high resistance state to conduction state, and the microprocessor is also connected with optical radar circuit and defrosting circuit for shelter detection.

2. A self-test device for a flame detector as defined in claim 1, characterized in that The circuit of the infrared sensor comprises a power supply filter capacitor C18 and a capacitor C21 connected with the infrared sensor S1, a monitoring circuit for real-time monitoring connected at both ends of the capacitor C18, and a band-pass filter and a signal amplification circuit for outputting voltage signal.

3. A self-test device for a flame detector as defined in claim 2, characterized in that The real-time monitoring circuit comprises a resistor R22 and a resistor R26 connected in series and then connected to both ends of the capacitor C18, and a resistor R25 and a capacitor C22 connected in series and then connected in parallel with the resistor R26; the band-pass filter and the signal amplification circuit comprise an operational amplifier U4, whose same direction end is connected with one end of a capacitor C17, a resistor R20 and a capacitor C16, whose opposite phase end is connected with one end of a resistor R24 and a capacitor C23, and whose output end is connected with one end of a resistor R23, and the other end of the resistor R23 is connected in series with a capacitor C20 and grounded.

4. The self-test apparatus for a flame detector of claim 1, wherein, The circuit of the ultraviolet sensor comprises a voltage circuit for generating ultraviolet light required during working, a signal expansion signal circuit, an ultraviolet circuit monitoring circuit and a low-pass filter and a signal expansion circuit, which are connected with the ultraviolet sensor D5.

5. A self-test device for a flame detector as defined in claim 4, characterized in that The voltage circuit comprises a transformer T1, one group of pins of which are connected to a diode D1 and a capacitor C2, and the other group of pins of which are connected to a power supply end through a capacitor C1, a diode D2 and a capacitor C5, and one end of the diode D2 and a triode Q1; the signal expansion signal circuit comprises a chip U2A and one end of a resistor R2, a capacitor C6, a capacitor C7 and a resistor R1 connected with the chip U2A, and the other end of the capacitor C7 and the resistor R1 is connected with an amplifier U1B, and the amplifier U1B, a resistor R4 and a resistor R8 are connected with each other as an expansion signal of UV_T signal for controlling the triode Q1 to be turned on, and the ultraviolet circuit monitoring circuit comprises one end of the ultraviolet sensor D5 and a resistor R10 connected with the ultraviolet sensor D5, and one end of a resistor R12 and a capacitor C10 connected with the other end of the resistor R10, and the other end of the capacitor C10 is connected with U3.

6. A self-test device for a flame detector as defined in claim 4, characterized in that The low-pass filter and the signal expansion circuit comprise one end of a resistor R19 and a resistor R16 connected with the ultraviolet sensor D5, and the other end of the resistor R16 is connected with an operational amplifier U1A, and the resistor R16 is also connected in parallel with a capacitor C13 and a capacitor C14, and the operational amplifier U1A is connected with a chip U2B through a resistor R17, and the chip U2B is also connected with a capacitor C15, a resistor R13 and a capacitor C11.

7. The self-test apparatus for a flame detector of claim 1, wherein, The circuit of the infrared light source comprises a triode Q2 and a resistor R22 connected in sequence with one end of an infrared light source D4 and grounded, and the other end of the infrared light source D4 is connected with an operational amplifier U5, and the operational amplifier U5 is also connected in parallel with a resistor R21, a capacitor C19 and a resistor R19 connected in series, and the operational amplifier U5 and the triode Q2 are connected with each other through a resistor R20.

8. The self-test apparatus for a flame detector of claim 1, wherein, The circuit of the ultraviolet light source comprises: an external light source D5 connected with the collector of a triode Q3, the emitter of the triode Q3 connected with a resistor R26 and grounded, and the base of the emitter of the triode Q3 connected with a resistor R25 and an operational amplifier U6 in sequence, the operational amplifier U6 further connected with a resistor R23, a resistor R24 and a capacitor C20.

9. The self-test apparatus for a flame detector of claim 1, wherein, The optical radar circuit comprises a chip U8 and resistors R44, R45, R46, a capacitor C23 and a capacitor C24 connected with the chip U8.

10. The self-test apparatus for a flame detector of claim 1, wherein, The defrosting circuit further comprises heating resistors R27-R35 arranged close to the glass window, a resistor R37, a resistor R40, a capacitor C21, an operational amplifier U7, a resistor R39, a triode Q4 and a resistor R42 connected with each other to provide a starting control signal for the heating resistors R27-R35.

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