TWI765190B - flame detection method - Google Patents

Abstract

The present invention provides a flame detection method, which adopts a sensing device to detect the infrared radiation generated by the flame in the environment, and generates a sensing signal, and then processes the sensing signal through an amplifying unit and a converting unit, and finally processes the sensing signal. The unit judges whether it is a flame signal and judges its flame level value, and also provides two sensing devices or three sensing devices to detect the environment at the same time. The difference is that it can judge whether it is an interference signal or a human body heat signal at the same time. The interference signal or human body heat signal does not need to judge whether it is a flame signal and determine the flame level value, and then compare the condition threshold to judge whether it is a fire alarm signal, which can greatly improve the accuracy of flame detection and reduce the false alarm rate, and Not affected by thermal radiation, hands, high temperature objects, sunlight and human body heat in the environment.

Description

flame detection method

The present invention relates to a flame detection method.

The flame is composed of various combustion products, intermediates, high-temperature gases, hydrocarbons and inorganic substances as the main body of high-temperature solid particles. The thermal radiation of the flame has discrete-spectrum gas radiation and continuous-spectrum solid radiation. The flame radiation intensity and wavelength distribution of different combustors are different, but in general, the 1~2μm near-infrared wavelength region corresponding to the flame temperature has the largest radiation intensity. For example, the wavelength of flame radiation intensity when gasoline is burned.

The flame sensor is composed of high-temperature solid particles with various combustion products, intermediates, high-temperature gases, hydrocarbon substances and inorganic substances as the main body. The thermal radiation of the flame has discrete-spectrum gas radiation and continuous-spectrum solid radiation. Different combustion The flame radiation intensity and wavelength distribution of the object are different, but in general, the near-infrared wavelength domain and the ultraviolet light domain corresponding to the flame temperature have a large radiation intensity. According to this characteristic, a flame sensor can be made.

The functional use of the far-infrared flame sensor, which can be used to detect fire sources or some other heat sources with wavelengths in the range of 700nm to 1000nm. In robot competitions, far-infrared flame probes play a very important role. Far-infrared flame sensing The detector can detect infrared light with wavelengths in the range of 700nm to 1000nm, and the detection angle is 60. When the wavelength of infrared light is around 880nm, its sensitivity reaches the maximum. The far-infrared flame probe converts the change of the intensity of the external infrared light into the change of the current, which is reflected as the change of the value in the range of 0 to 255 through the A/D converter. The stronger the external infrared light, the smaller the value; the weaker the infrared light, the larger the value.

In the prior art, it is known from Patent No. TW I421475 B that the pyroelectric element in the infrared filter is used to selectively pass the infrared rays of the first selected wavelength (4.3 μm to 4.4 μm) and the infrared rays of the second selected wavelength (3.9 μm) respectively. The first selected wavelength is composed of a specific wavelength generated by the resonant radiation of _CO2 gas caused by the flame, and the second selected wavelength is a reference wavelength other than the specific wavelength. After the signal of sensing flame wavelength and the signal of sensing non-flame wavelength are combined, they are processed by related components to determine whether there is flame generation in the environment.

While the detector of the patent number CN 206249521U includes a radiation sensing device and a processing unit, the radiation sensing device includes a first radiation sensor for sensing radiation of a first wavelength and outputting a first signal, and a first radiation sensor for sensing a second The radiation of the wavelength and the second radiation sensor that outputs the second signal, the first wavelength is a wavelength different from the wavelength range of the characteristic spectrum of the flame to be measured, and the second wavelength is the characteristic wavelength of the flame to be measured, that is, the spectrum of the flame to be measured includes The second wavelength, while the first wavelength is not included in the spectrum of the flame to be measured. When judging, when the first signal exists, the processing unit judges that there is no combustion flame, because the spectrum of the flame to be measured does not include the first wavelength, and the first wavelength is used to judge the signal to be measured. , indicating that the signal to be measured is not a burning flame, and the processing unit judges that there is no burning flame, so the new type also needs to be equipped with two radiation sensors, one for sensing flame wavelengths, and the other for sensing non-flame wavelengths.

However, in the prior art, an additional element for sensing non-flame wavelengths must be provided, and the two signals must be used as the way to judge the flame. How to simplify the design of the flame detector and simplify the judgment process while taking into account its accuracy , which is a subject to be overcome by those skilled in the related fields.

The main purpose of the present invention is to provide a flame detection method, which uses the infrared spectrum in the middle range to analyze the infrared radiation generated in the flame, and the infrared sensor can detect the carbon dioxide component generated in the flame and receive the signal. The analysis is combined with applicable digital and analog data processing to output alarm data.

In order to achieve the above object, a first embodiment of the present invention discloses a flame detection method, the steps of which include: detecting an infrared ray through a sensing device to generate a sensing signal; receiving the sensing signal to an amplifying unit, and performing a filtering signal processing and an amplifying signal processing to generate an amplified signal; receiving the amplified signal to a converting unit, and performing analog-to-digital conversion to generate a digital signal; receiving The digital signal is sent to a processing unit, and judges whether the digital signal is a flame signal according to a first threshold value; when the digital signal is the flame signal, the processing unit confirms that the digital signal is the flame signal according to a second threshold value flame signal; when the digital signal is confirmed as the flame signal, the processing unit interprets a flame level value of the flame signal according to the peak value of the digital signal; the processing unit judges a flame level value as a condition threshold according to the flame level value comparison fire alarm; and wherein the wavelength of the infrared rays is 3 μm to 5 μm.

In the first embodiment of the present invention, the sensing device is provided with an infrared sensing probe.

The first embodiment of the present invention further includes: the processing unit generates a warning signal to an alarm unit according to the fire alarm signal, and drives a warning light signal.

A second embodiment of the present invention discloses a flame detection method, the steps of which include: detecting an infrared ray through a first sensing device and a second sensing device to generate a first sensing signal and a second sensing signal sensing signal; receiving the first sensing signal and the second sensing signal to an amplifying unit, and performing a filtering signal processing and an amplified signal processing to generate a first amplified signal and a second amplified signal; receiving The first amplified signal and the second amplified signal are sent to a conversion unit, and analog-to-digital conversion is performed to generate a first digital signal and a second digital signal; the first digital signal is received to a processing unit, and according to a The first threshold value determines whether the first digital signal is an interference signal; when the first digital signal is not an interference signal, the second digital signal is received to the processing unit, and the second digital signal is determined according to a second threshold value Whether the signal is a flame signal; when the second digital signal is the flame signal, the processing unit confirms that the second digital signal is the flame signal according to a third threshold value; when the second digital signal is confirmed as the flame signal When , the processing unit interprets a flame level value of the flame signal according to the peak value of the second digital signal; the processing unit determines a fire alarm signal according to the flame level value comparison with a condition threshold; and the wavelength of the infrared ray 3μm to 5μm.

In the second embodiment of the present invention, both the first sensing device and the second sensing device are provided with an infrared sensing probe.

The second embodiment of the present invention further includes: the processing unit generates a warning signal to an alarm unit according to the fire alarm signal, and drives a warning light signal.

A third embodiment of the present invention discloses a flame detection method, the steps of which include: a flame detection method, the steps of which include: detecting through a first sensing device, a second sensing device and a third sensing device measuring an infrared ray to generate a first sensing signal, a second sensing signal and a third sensing signal; receiving the first sensing signal, the second sensing signal and the third sensing signal to a an amplifying unit that performs a filtering signal processing and an amplified signal processing to generate a first amplified signal, a second amplified signal and a third amplified signal; receives the first amplified signal, the second amplified signal and the third amplified signal Amplify the signal to a conversion unit, and perform analog-to-digital conversion to generate a first digital signal, a second digital signal and a third digital signal; receive the first digital signal to a processing unit, and according to a first threshold value to determine whether the first digital signal is a human body thermal energy signal; when the first digital signal is not a human body thermal energy signal, receive the second digital signal to the processing unit, and determine the second digital signal according to a second threshold value Whether it is an interference signal; when the second digital signal is not the interference signal, receive the third digital signal to the processing unit, and judge whether the third digital signal is a flame signal according to a third threshold value; when the When the third digital signal is the flame signal, the processing unit confirms that the third digital signal is the flame signal according to a fourth threshold value; when the third digital signal is confirmed to be the flame signal, the processing unit determines the third digital signal to be the flame signal The peak value of the digital signal interprets a flame level value of the flame signal; the processing unit judges a fire alarm signal according to the flame level value comparison with a condition threshold; and the wavelength of the infrared rays is 3 μm to 5 μm.

In the third embodiment of the present invention, the first sensing device, the second sensing device and the third sensing device are all provided with an infrared sensing probe.

The third embodiment of the present invention further includes: the processing unit generates a warning signal to an alarm unit according to the fire alarm signal, and drives a warning light signal.

S1~S47: Steps

1: Sensing device

11: Sensing signal

2: Amplifying unit

21: Amplify the signal

3: Conversion unit

31: digital signal

4: Processing unit

41: Warning Signal

5: Alarm unit

51: Warning lights

6: The first sensing device

61: The first sensing signal

7: Second sensing device

71: Second sensing signal

8: Amplification unit

81: The first amplified signal

82: Second amplified signal

9: Conversion unit

91: The first digital signal

92: Second digital signal

10: Processing unit

101: Warning Signal

11: Alarm unit

111: Warning light signal

12: The first sensing device

121: The first sensing signal

13: Second sensing device

131: Second sensing signal

14: The third sensing device

141: The third sensing signal

15: Amplification unit

151: The first amplified signal

152: Second amplified signal

153: The third amplified signal

16: Conversion unit

161: The first digital signal

162: Second digital signal

163: The third digital signal

17: Processing unit

171: Warning Signal

18: Alarm unit

181: Warning light signal

Figure 1: It is a flow chart of the method of the first embodiment of the present invention; Figure 2: It is a partial flow chart of the first embodiment of the present invention; Figure 3: It is the first embodiment of the present invention. Schematic diagram of method execution; Figure 4: It is a flow chart of the method of the second embodiment of the present invention; Figure 5: It is a schematic diagram of the execution of the method of the second embodiment of the present invention; Figure 6: It is the first embodiment of the present invention. The flow chart of the method of the third embodiment; and FIG. 7 : it is a schematic diagram of the execution of the method of the third embodiment of the present invention.

In order to make your examiners have a further understanding and understanding of the features of the present invention and the effects achieved, I would like to add examples and explanations, and the explanations are as follows: Hereinafter, the present invention will be described in detail by illustrating various embodiments of the present invention by means of the drawings. The concepts of the invention may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein.

The present invention is a flame detection method, which detects infrared rays through a sensing device, and the wavelength of the infrared rays detected is 3 μm to 5 μm. The amplified signal is generated, and further analog-to-digital conversion is performed by the conversion unit to generate a digital signal. Finally, the processing unit judges whether the digital signal is a flame signal according to the first threshold value. The two thresholds confirm that the digital signal is a flame signal.

First, please refer to FIG. 1 , which is a flow chart of the method according to the first embodiment of the present invention, as shown in the figure; the steps of the flame detection method of the present invention include: Step S1 : detecting an infrared ray through a sensing device to generating a sensing signal; step S3: receiving the sensing signal to an amplifying unit, and performing a filtering signal processing and an amplified signal processing to generate an amplified signal; Step S5: Receive the amplified signal to a conversion unit, and perform analog-to-digital conversion to generate a digital signal; Step S7: Receive the digital signal to a processing unit, and determine whether the digital signal is a digital signal according to a first threshold value flame signal; step S9: the processing unit confirms that the digital signal is the flame signal according to a second threshold value; step S11: the processing unit interprets a flame level value of the flame signal according to the peak value of the digital signal; and step S13: The processing unit judges a fire alarm according to the flame level value and a condition threshold value.

As shown in step S1, please also refer to FIG. 3, which is a schematic diagram of the execution of the method according to the first embodiment of the present invention. As shown in the figure, this embodiment detects infrared rays through the sensing device 1, wherein the wavelength of the infrared rays is 3 μm to 5 μm to generate the sensing signal 11, wherein the sensing device 1 is provided with an infrared sensing probe, which uses the infrared spectrum in the middle range to analyze the infrared radiation generated in the flame, and the infrared sensing probe used in this embodiment The composition of the carbon dioxide produced by the flame can be judged by the wavelength band measured, wherein the carbon dioxide produces carbon dioxide resonance emission in the flame, so if the wavelength band of the infrared radiation measured by the sensing device 1 is 4.4 μm, it means that it is possible to measure the presence of flames.

As shown in step S3, the amplified signal 21 of this embodiment includes a first-stage amplifying circuit and a second-stage amplifying circuit. The first-stage amplifying circuit performs filtering signal processing on the sensing signal 11 received by the sensing device 1, and the first-stage amplifying circuit processes the sensing signal 11 received by the sensing device 1. The second-stage amplifying circuit processes the sensing signal 11 after filtering the signal to amplify the signal, and finally generates the amplified signal.

As shown in step S5, the conversion unit 3 performs analog-to-digital conversion on the amplified signal to be judged, that is, the amplified signal originally an analog signal is converted into a digital signal 31, which is provided to the processing unit 4 for the judgment step.

As shown in step 7, the processing unit 4 receives the digital signal 31, and determines whether the digital signal 31 is a flame signal according to the first threshold value. In the first embodiment, the flame signal is judged by Whether it is a flame is determined by comparing the peak value of the digital signal 31 with the first threshold value, and the first threshold value is set to 0.8V. Therefore, when the peak value of the digital signal 31 is lower than 0.8V, it is determined as a non-flame signal, and the processing unit 4 Control the sensing device 1 to return to step S1 to re-detect. On the contrary, if the digital signal 31 is determined to be a flame signal, that is, when the peak value of the digital signal 31 is higher than 0.8V, it is determined to be a flame signal, and the processing unit 4 proceeds to step S9.

As shown in step S9, the processing unit 4 will confirm whether the digital signal 31 is a flame signal according to the second threshold value, and the second threshold value is set to 0.4V, so when the peak value of the digital signal 31 is lower than 0.4V, it is determined to be a non-flame signal , then the processing unit 4 controls the sensing device 1 to return to step S1 for re-detection. On the contrary, if the digital signal 31 is confirmed as a flame signal, that is, when the peak value of the digital signal 31 is higher than 0.4V, it is identified as a flame signal, then proceed to step S11.

As shown in step S11, the processing unit 4 will judge the flame level value according to the peak value of the digital signal 31, wherein the flame level value is further divided into the first level flame level value is more than 2V; the second level flame level value is 1.5V -2V; the third-level flame level value is 1V-1.5V; and below 1V is judged as non-flame.

As shown in step S13, the processing unit 4 compares the condition threshold value and then judges whether it is a fire according to the flame degree value, wherein the condition threshold value is counted at the same time after the processing unit 4 has completed 1-15 peak records ranging from 1 to 15 times. The number of the first-level flame level value, the second-level flame level value, and the third-level flame level value, when the number of flame level values meets the conditions of large fire, medium fire or small fire, it is judged as a fire alarm. The condition is that the first-level flame level value reaches three times; the medium-fire condition is that the first-level flame level value and the third-level flame level value are once each, and the second-level flame level value is three times; the small fire condition is the first-level flame level value. Once each with the second level flame level value and the third level flame level value up to five times.

Referring to FIG. 2, which is a partial flow chart of the first embodiment of the present invention, as shown in the figure; the flame detection method of the present invention further comprises: Step S2: the processing unit generates a warning signal to a fire alarm signal according to the fire alarm signal. alarm unit, and drive a warning light.

As shown in step S2, when the processing unit 4 judges that the number of times the flame level value does not meet the large fire condition, the medium fire condition or the small fire condition, it is judged that it is not a fire alarm, and the processing unit 4 will control the sensing device 1 to re-detect environment, then return to step S1, on the contrary, when the processing unit 4 judges that the number of times of the flame level value meets the big fire condition or the medium fire condition or the small fire condition, then judges the fire alarm signal, and will continue to execute step S6 to generate the warning signal 41 to the alarm unit 5, and drive the warning light 51.

Next, in order to achieve the flame detection method of the present invention, please refer to FIG. 4 , which is a flow chart of the method according to the second embodiment of the present invention. As shown in the figure, the difference between the second embodiment of the present invention and the first embodiment is that the second embodiment adopts the first sensing device and the second sensing device, and simultaneously receives the first sensing signal and the second sensing The signal is used as detection, and the steps include: Step S15: Detect an infrared ray through a first sensing device and a second sensing device, and generate a first sensing signal and a second sensing signal; Step S17: Receive the first sensing signal and the second sensing signal to an amplifying unit, and perform a filtering signal processing and an amplified signal processing to generate a first amplified signal and a second amplified signal; Step S19: Receive the The first amplified signal and the second amplified signal are sent to a conversion unit, and analog-to-digital conversion is performed to generate a first digital signal and a second digital signal; Step S21: Receive the first digital signal to a processing unit, and Determine whether the first digital signal is an interference signal according to a first threshold; Step S23: Receive the second digital signal to the processing unit, and determine whether the second digital signal is a flame signal according to a second threshold ; Step S25: the processing unit confirms that the second digital signal is the flame signal according to a third threshold value; Step S27: the processing unit interprets a flame level value of the flame signal according to the peak value of the second digital signal; and step S29: The processing unit judges a fire alarm according to the flame level value comparing with a condition threshold value.

As shown in step S15, please also refer to FIG. 5, which is a schematic diagram of the execution of the method according to the second embodiment of the present invention. As shown in the figure, this embodiment adopts the first sensing device 6 and the second sensing device 7 Detects infrared rays, generates a first sensing signal 61 and a second sensing signal 71 respectively, and detects the carbon dioxide component in the flame through the combination of the two sensing devices, which can reduce the false alarm rate, and is free from heat radiation, hand or high temperature Object influence.

In this embodiment, both the first sensing device 6 and the second sensing device 7 are provided with an infrared sensing probe. As in step S17 and step S19, the amplifying unit 8 and the converting unit 9 in this embodiment are the same as those in the first embodiment, and the difference is only in the number of signals sensed by the sensing device, that is, receiving the first sensing signal 61 and the second sensing signal The test signal 71 is subjected to filtering signal processing and amplifying signal processing to generate a first amplified signal 81 and a second amplified signal 82, and receives the first amplified signal 81 and the second amplified signal 82 for analog-to-digital conversion to generate the first digital signal 91 and the second amplified signal 82. The second digital signal 92 will not be repeated here.

As shown in step S21, in this embodiment, the processing unit 10 receives the first digital signal 91, and determines whether the first digital signal 91 is an interference signal according to the first threshold value. In the second embodiment, the interference signal determination is performed by By comparing the peak value of the first digital signal 91 with the first threshold value to determine whether it is interference, and the first threshold value is set to 0.4V, therefore, when the peak value of the digital signal is higher than 0.4V, it is determined to be an interference signal, and the processing unit 10 Control the first sensing device 6 and the second sensing device 7 to return to step S23 for re-detection. On the contrary, if the first digital signal 91 is determined as a non-interference signal, that is, when the peak value of the first digital signal 91 is lower than 0.4V, it is determined as non-interference signal, the processing unit 10 proceeds to step S23.

As shown in step S23, the processing unit 10 receives the second digital signal 92, and determines whether the second digital signal 92 is a flame signal according to the second threshold value. In the second embodiment, the flame signal is judged through the second digital signal. The peak value of 92 is compared with the second threshold value to determine whether it is a flame, and the second threshold value is set to 0.8V. Therefore, when the peak value of the second digital signal 92 is lower than 0.8V, it is determined to be a non-flame signal, and the processing unit 10 controls The first sensing device 6 and the second sensing device 7 return to step S15 for re-detection. On the contrary, if the second digital signal 92 is determined as a flame signal, that is, when the peak value of the second digital signal 92 is higher than 0.8V, it is determined as a flame signal , the processing unit 10 proceeds to step S25.

As shown in step S25, the processing unit 10 will confirm whether the second digital signal 92 is a flame signal according to the third threshold value, and the third threshold value is set to 0.4V, so when the peak value of the second digital signal 92 is lower than 0.4V If it is determined that it is not a flame signal, the processing unit 10 controls the first sensing device 6 and the second sensing device 7 to return to step S1 to detect again. On the contrary, if the second digital signal 92 is confirmed to be a flame signal, that is, the second digital signal 92 is a flame signal. When the peak value is higher than 0.4V, it is identified as a flame signal, then step S27 and step S29 are executed successively. The method of interpreting the flame level value of this embodiment is the same as that of the first embodiment, the difference is only that the processing unit of this embodiment is based on the first embodiment. The peak value of the two digital signals 92 is judged to determine its flame level value, and whether it reaches the fire alarm signal to generate a warning signal 101 , and the fire alarm signal determined by the flame level value is continuously executed in step S2 of the first embodiment, and is transmitted according to the fire alarm signal. The warning signal 101 drives the warning light signal 111 of the warning unit 11, so the process thereof will not be repeated.

Next, in order to achieve the flame detection method of the present invention, please refer to FIG. 6 , which is a flow chart of the method according to the third embodiment of the present invention. As shown in the figure, the difference between the third embodiment of the present invention and the first embodiment is that the third embodiment adopts a first sensing device, a second sensing device and a third sensing device, and simultaneously receives the first sensing device The signal, the second sensing signal and the third sensing signal are used for detection, and the steps include: Step S31 : Detecting an infrared ray through a first sensing device, a second sensing device and a third sensing device, And generate a first sensing signal, a second sensing signal and a third sensing signal; Step S33: Receive the first sensing signal, the second sensing signal and the third sensing signal to amplify unit, and perform a filtering signal processing and an amplified signal processing to generate a first amplified signal, a second amplified signal and a third amplified signal; Step S35: Receive the first amplified signal, the second amplified signal and the The third amplifies the signal to a conversion unit, and performs analog-to-digital conversion to generate a first digital signal, a second digital signal and a third digital signal; Step S37: Receive the first digital signal to a processing unit, and determining whether the first digital signal is a human body thermal energy signal according to a first threshold value; Step S39: Receive the second digital signal to the processing unit, and determine whether the second digital signal is an interference signal according to a second threshold; Step S41: Receive the third digital signal to the processing unit, and determine whether the second digital signal is an interference signal; The third threshold value determines whether the third digital signal is a flame signal; Step S43 : the processing unit confirms that the third digital signal is the flame signal according to a fourth threshold value Step S45 : The processing unit determines according to the third digital signal and step S47 : the processing unit judges a fire alarm signal by comparing the flame level value with a condition threshold value.

As shown in step S31, please also refer to FIG. 7, which is a schematic diagram of the execution of the method according to the third embodiment of the present invention. As shown in the figure, this embodiment adopts the first sensing device 12 and the second sensing device 13 And the third sensing device 14 detects the environment, and generates a first sensing signal 121, a second sensing signal 131 and a third sensing signal 141 respectively, and detects the carbon dioxide component in the flame through the combination of the three sensing devices, At the same time, it outputs extremely high-accuracy alarm data for potentially dangerous phenomena, and is not affected by thermal radiation, hands, high-temperature objects, sunlight and human body heat, and can be used as outdoor or explosion-proof flame detection.

In this embodiment, the first sensing device 12 , the second sensing device 13 and the third sensing device 14 are all provided with an infrared sensing probe. As in step S33 and step S35, the amplifying unit 15 and the converting unit 16 of this embodiment are the same as the first embodiment, and the difference is only in the number of sensing signals, that is, receiving the first sensing signal 121 and the second sensing signal 131 and the third sensing signal 141 to perform filtering signal processing and amplifying signal processing to generate a first amplified signal 151, a second amplified signal 152 and a third amplified signal 153, and receive the first amplified signal 151, the second amplified signal 152 and the third amplified signal 153. The three-amplified signal 153 performs analog-to-digital conversion to generate a first digital signal 161 , a second digital signal 162 and a third digital signal 163 , so the process is not repeated here.

In step S37, in this embodiment, the processing unit 17 receives the first digital signal 161, and determines whether the digital signal is a human body thermal energy signal according to the first threshold value. The human body thermal energy signal is judged by comparing the peak value of the first digital signal 161 with the first threshold value to determine whether it is human body thermal energy, and the first threshold value is set to 0.4V, so when the peak value of the first digital signal 161 is higher than 0.4V If it is identified as a human body thermal energy signal, the processing unit 17 controls the first sensing device 12, the second sensing device 13 and the third sensing device 14 to return to step S31 to detect again. On the contrary, if the first digital signal 161 determines that it is not human body thermal energy The signal, that is, when the peak value of the first digital signal 161 is lower than 0.4V, is determined as a non-human body thermal energy signal, and the processing unit 17 proceeds to step S39.

As shown in step S39, the processing unit 17 receives the second digital signal 162, and determines whether the second digital signal 162 is an interference signal according to the second threshold value. In the third embodiment, the interference signal is determined through the second digital signal. The peak value of 162 is compared with the second threshold value to determine whether it is interference, and the second threshold value is set to 0.4V. Therefore, when the peak value of the second digital signal 162 is higher than 0.4V, it is determined to be an interference signal, and the processing unit 17 controls the first digital signal. The first sensing device 12 , the second sensing device 13 and the third sensing device 14 return to step S31 for re-detection. On the contrary, if the second digital signal 162 determines a non-interference signal, that is, the peak value of the second digital signal 162 is lower than 0.4 When V is determined to be a non-interference signal, the processing unit 17 proceeds to step S41.

As shown in step S41, the processing unit 17 receives the third digital signal 163, and determines whether the third digital signal 163 is a flame signal according to the third threshold value. In the third embodiment, the flame signal is judged through the third digital signal The peak value of 163 is compared with the third threshold value to determine whether it is a flame, and the third threshold value is set to 0.8V. Therefore, when the peak value of the third digital signal 163 is lower than 0.8V, it is determined to be a non-flame signal, and the processing unit 17 controls The first sensing device 12 , the second sensing device 13 and the third sensing device 14 return to step S31 for re-detection. On the contrary, if the third digital signal 163 is determined to be a flame signal, that is, the peak value of the third digital signal 163 is higher than When 0.8V is identified as a flame signal, the processing unit 17 proceeds to step S43.

As shown in step S43, the processing unit 17 will confirm whether the third digital signal 163 is a flame signal according to the fourth threshold value, and the fourth threshold value is set to 0.4V, so when the peak value of the third digital signal 163 is lower than 0.4V If it is determined that it is not a flame signal, the processing unit 17 controls the first sensing device 12, the second sensing device 13 and the third sensing device 14 to return to step S31 to re-detect. On the contrary, if the third digital signal 163 is confirmed to be a flame signal, That is, when the peak value of the third digital signal 163 is higher than 0.4V If it is identified as a flame signal, step S45 and step S47 are executed successively. The method of interpreting the flame level value of this embodiment is the same as that of the first embodiment, the difference is only that the processing unit of this embodiment is based on the peak value of the third digital signal 163 The fire alarm signal 171 is generated by interpreting the flame level value and whether the fire alarm signal is reached, and the fire alarm signal determined by the flame level value is then executed in step S2 of the first embodiment, and the alarm signal 171 is sent to the alarm unit according to the fire alarm signal. 18 drives its warning light 181, so its process will not be repeated.

To sum up, the present invention is a flame detection method, which uses a sensing device to detect infrared rays in a flame, and determines the composition of carbon dioxide by analyzing the wavelength of the infrared rays, and increases the number of sensing devices, which greatly improves the performance of the flame detection method. Improve the accuracy of flame detection and reduce the false alarm rate, and make the sensing device not affected by thermal radiation, hands, high-temperature objects, sunlight and human body heat.

Therefore, the present invention is indeed novel, progressive and available for industrial use, and it should meet the requirements for patent application in my country's patent law.

However, the above descriptions are only preferred embodiments of the present invention, and are not intended to limit the scope of implementation of the present invention. All changes and modifications made in accordance with the shape, structure, features and spirit described in the scope of the patent application of the present invention are equivalent. , shall be included in the scope of the patent application of the present invention.

S1~S7: Steps

Claims (6)

A flame detection method, the steps comprising: detecting an infrared ray through a first sensing device and a second sensing device to generate a first sensing signal and a second sensing signal; receiving the first sensing The signal and the second sensing signal are sent to an amplifying unit, and a filtering signal processing and an amplifying signal processing are performed to generate a first amplified signal and a second amplified signal; the first amplified signal and the second amplified signal are received The signal is sent to a conversion unit, and analog-digital conversion is performed to generate a first digital signal and a second digital signal; the first digital signal is received to a processing unit, and the first digital signal is judged according to a first threshold value Whether it is an interference signal; when the first digital signal is not an interference signal, receive the second digital signal to the processing unit, and judge whether the second digital signal is a flame signal according to a second threshold value; when the first digital signal is a flame signal; When the two digital signals are the flame signal, the processing unit confirms that the second digital signal is the flame signal according to a third threshold value; when the second digital signal is confirmed to be the flame signal, the processing unit determines the second digital signal to be the flame signal The peak value of the signal interprets a flame level value of the flame signal; the processing unit judges a fire alarm signal according to the flame level value comparison with a condition threshold; and the wavelength of the infrared rays is 3 μm to 5 μm. The flame detection method as described in claim 1, wherein the first sensing device and the second sensing device are both provided with an infrared sensing probe. The flame detection method described in item 1 of the scope of the patent application further comprises: the processing unit generates a warning signal to an alarm unit according to the fire warning signal, and drives a warning light signal. A flame detection method, the steps comprising: Detecting an infrared ray through a first sensing device, a second sensing device and a third sensing device to generate a first sensing signal, a second sensing signal and a third sensing signal; receiving The first sensing signal, the second sensing signal and the third sensing signal are sent to an amplifying unit, and a filtering signal processing and an amplified signal processing are performed to generate a first amplified signal and a second amplified signal and a third amplified signal; receive the first amplified signal, the second amplified signal and the third amplified signal to a conversion unit, and perform analog-to-digital conversion to generate a first digital signal, a second digital signal and a a third digital signal; receive the first digital signal to a processing unit, and determine whether the first digital signal is a human body thermal energy signal according to a first threshold value; when the first digital signal is not a human body thermal energy signal, receive the The second digital signal is sent to the processing unit, and according to a second threshold value, it is determined whether the second digital signal is an interference signal; when the second digital signal is not the interference signal, the third digital signal is received to the processing unit , and judges whether the third digital signal is a flame signal according to a third threshold value; when the third digital signal is the flame signal, the processing unit confirms that the third digital signal is the flame according to a fourth threshold value signal; when the third digital signal is confirmed as the flame signal, the processing unit interprets a flame level value of the flame signal according to the peak value of the third digital signal; the processing unit compares a condition threshold value according to the flame level value It is judged as a fire alarm; and wherein the wavelength of the infrared rays is 3 μm to 5 μm. The flame detection method as described in claim 4, wherein the first sensing device, the second sensing device and the third sensing device are all provided with an infrared sensing probe. The flame detection method described in Item 4 of the scope of the application further includes: The processing unit generates a warning signal to an alarm unit according to the fire alarm signal, and drives a warning light signal.

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