Optical flame detection device

Abstract

The utility model relates to the technical field of flame detection, in particular to an optical flame detection device which mainly comprises a blue light sensor, an orange light sensor, an exclusive OR circuit module and a main control unit, the blue light sensor is connected with the exclusive OR circuit module through a first amplification comparison unit, and the orange light sensor is connected with the main control unit through a second amplification comparison unit. And the orange light sensor is connected with the XOR circuit module through the second amplification comparison unit. Through the above structure, the blue light sensor and the orange light sensor collect light signals, the amplification and comparison unit is used for receiving and amplifying measured values of the blue light sensor and the orange light sensor, through the light characteristics of real flame, the amplified analog quantity is compared with a standard value, and a digital quantity signal for a subsequent circuit to make logic judgment is output. True value logic or false value logic is output through the XOR circuit module to obtain a final flame recognition result, so that the recognition accuracy of current flame detection is improved as much as possible, and the false alarm rate is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of flame detection, and more specifically, to an optical flame detection device. Background Art

[0002] Spectral signal: The spectral signal of a flame can be easily obtained through filters installed on a set of infrared sensors. For example, a CO2 flame emits light at 4.3 microns, a hydrogen flame emits light at 2.7 microns, and a CH4 flame emits light at 3.3 microns. Light between 3.09 and 3.95 microns is usually used as reference light. The most common way to distinguish a flame from all other light sources is to look at the ratio of this different spectrum.

[0003] Time-varying signal of a flame: The time signal of a flame is generated by the oxygen supply efficiency. An oxygen-rich flame emits blue light. An oxygen-deficient flame has more orange emission. The alternation of blue and orange results in the flickering of the flame. The flickering light may also be caused by vibrating light. Therefore, the flickering light will become a potential false alarm source for many flame detectors. Summary of the Utility Model

[0004] The purpose of the utility model is to provide an optical flame detection device to solve the problem of false alarms in existing flame detectors.

[0005] Specifically, the characteristics of a real flame are as follows: According to the different oxygen contents, the proportions of blue light and orange light generated by the flame at the same moment are different, and it oscillates between 5 Hz and 20 Hz, showing a characteristic of one increasing while the other decreasing. This characteristic applies to any moment. In contrast, the proportions of blue light and orange light emitted by other flickering lights other than real flames at the same moment do not have such a characteristic. Based on this difference, real flames and false flames can be effectively distinguished.

[0006] The embodiments of the utility model are realized through the following technical solutions:

[0007] An optical flame detection device includes a blue light sensor, an orange light sensor, an exclusive OR circuit module, and a main control unit. The blue light sensor is connected to the exclusive OR circuit module through a first amplification and comparison unit. The orange light sensor is connected to the exclusive OR circuit module through a second amplification and comparison unit. The first amplification and comparison unit is used to detect the analog quantity of the blue light sensor, amplify it, and compare it with a standard value, and output a digital quantity signal. The second amplification and comparison unit is used to detect the analog quantity of the orange light sensor, amplify it, and compare it with a standard value, and output a digital quantity signal. The exclusive OR circuit module is connected to the main control unit and is used to receive the signals of the first amplification and comparison unit and the second amplification and comparison unit and output the exclusive OR result to the main control unit.

[0008] Preferably, the first amplification and comparison unit includes a first amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor, and a ninth resistor;

[0009] The blue light sensor is connected to the third resistor, and the third resistor is connected to the non-inverting input terminal of the first amplifier and the fourth resistor;

[0010] The inverting input terminal of the first amplifier is connected to the first resistor and the second resistor, and the output terminal of the first amplifier is connected to the exclusive OR circuit module, the fourth resistor, and the fifth resistor.

[0011] Preferably, the second amplification and comparison unit includes a second amplifier, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor, and a tenth resistor;

[0012] The orange light sensor is connected to the seventh resistor, and the seventh resistor is connected to the non-inverting input terminal of the second amplifier and the eighth resistor;

[0013] The inverting input terminal of the second amplifier is connected to the fifth resistor and the sixth resistor, and the output terminal of the second amplifier is connected to the exclusive OR circuit module, the eighth resistor, and the tenth resistor.

[0014] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0015] Adopting the structure provided by the embodiment of the present invention, it mainly includes a blue light sensor, an orange light sensor, an exclusive OR circuit module, and a main control unit. The blue light sensor is connected to the exclusive OR circuit module through the first amplification and comparison unit, and the orange light sensor is connected to the exclusive OR circuit module through the second amplification and comparison unit. The exclusive OR circuit module is connected to the main control unit, and is used to receive the amplified optical signal and output the exclusive OR result to the main control unit. Through the above structure, the blue light sensor and the orange light sensor are used to collect optical signals. The amplification and comparison unit is used to receive and amplify the measured values of the blue light sensor and the orange light sensor, and compare the amplified analog quantity with the standard value according to the characteristics of the light of the real flame, and output a digital quantity signal for subsequent circuit logic judgment. The exclusive OR circuit module outputs a true logic or a false logic to obtain the final flame recognition result, so as to improve the recognition accuracy of the current flame detection as much as possible and reduce the false alarm rate. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 is a structural schematic diagram of the present utility model;

[0018] Figure 2 is a blue light flame waveform diagram of the present utility model;

[0019] Figure 3 is an orange light flame waveform diagram of the present utility model.

[0020] Icons: R1 - the first resistor, R2 - the second resistor, R3 - the third resistor, R4 - the fourth resistor, R5 - the fifth resistor, R6 - the sixth resistor, R7 - the seventh resistor, R8 - the eighth resistor, R9 - the ninth resistor, R10 - the tenth resistor, U1 - the first amplifier, U2 - the second amplifier, U3 - the exclusive - OR circuit module. Specific embodiments

[0021] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. Components of the embodiments of the present utility model described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0022] Please refer to Figure 1 , an optical flame detection device, comprising a blue light sensor, an orange light sensor, an exclusive - OR circuit module U3 and a main control unit. The blue light sensor is connected to the exclusive - OR circuit module U3 through a first amplification and comparison unit. The orange light sensor is connected to the exclusive - OR circuit module U3 through a second amplification and comparison unit. The first amplification and comparison unit is used to detect the analog quantity detected by the blue light sensor, amplify it and compare it with a standard value, and output a digital quantity signal. The second amplification and comparison unit is used to detect the analog quantity detected by the orange light sensor, amplify it and compare it with a standard value, and output a digital quantity signal. The exclusive - OR circuit module U3 is connected to the main control unit and is used to receive the signals of the first amplification and comparison unit and the second amplification and comparison unit and output an exclusive - OR result to the main control unit.

[0023] Adopting the structure provided by the implementation of the present utility model, it mainly includes a blue light sensor, an orange light sensor, an exclusive-OR circuit module U3, and a main control unit. The blue light sensor is connected to the exclusive-OR circuit module U3 through a first amplification and comparison unit, and the orange light sensor is connected to the exclusive-OR circuit module U3 through a second amplification and comparison unit. The exclusive-OR circuit module U3 is connected to the main control unit, and is used to receive the amplified optical signal and output the exclusive-OR result to the main control unit. Through the above structure, the optical signal is collected by the blue light sensor and the orange light sensor. According to the optical characteristics of the real flame, how the blue light and orange light of the flame should present signals. The exclusive-OR circuit module U3 outputs true logic or false logic to obtain the final flame recognition result, so as to improve the recognition accuracy of the current flame detection as much as possible and reduce the false alarm rate.

[0024] In an exemplary embodiment of the present utility model, the first amplification and comparison unit includes a first amplifier U1, a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, and a ninth resistor R9;

[0025] The blue light sensor is connected to the third resistor R3, and the third resistor R3 is connected to the non-inverting input terminal of the first amplifier U1 and the fourth resistor R4;

[0026] The inverting input terminal of the first amplifier U1 is connected to the first resistor R1 and the second resistor R2, and the output terminal of the first amplifier U1 is connected to the exclusive-OR circuit module U3, the fourth resistor R4, and the fifth resistor R5.

[0027] In an exemplary embodiment of the present utility model, the second amplification and comparison unit includes a first amplifier U1, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, an eighth resistor R8, and a tenth resistor R10;

[0028] The orange light sensor is connected to the seventh resistor R7, and the seventh resistor R7 is connected to the non-inverting input terminal of the second amplifier U2 and the eighth resistor R8;

[0029] The inverting input terminal of the second amplifier U2 is connected to the fifth resistor R5 and the sixth resistor R6, and the output terminal of the second amplifier U2 is connected to the exclusive-OR circuit module U3, the eighth resistor R8, and the tenth resistor R10.

[0030] Wherein, a capacitor can be set between the first amplification and comparison unit and the blue light sensor, or between the second amplification and comparison unit and the orange light sensor to filter out the DC signal. Therefore, the amplifier only acts on the changing signal. Any additional signal will have a true logic of 1. A signal from high to low will be a false logic of 0.

[0031] Wherein, the models of the first amplifier U1 and the second amplifier U2 are LM2903, the model of the exclusive-OR circuit module U3 is 74HC86, and the model of the main control device is TiAC.

[0032] As Figure 2 shown, over time, the blue light oscillates between 5 hz and 20 hz, and what defines the rising is the real fire.

[0033] As Figure 3 shown, over time, the orange light oscillates at the same frequency as the blue light, but lags by 180 degrees, and what defines the rising is the real fire.

[0034] According to the above-mentioned logic value output method of the exclusive-OR circuit module U3, when the blue light is rising, the true value logic 1 is output, and when it drops from high to low, the true value logic is 0. Similarly, when the orange light is rising, the true value logic 1 is output, and when it drops from high to low, the true value logic is 0.

[0035] It should be noted that the above judgment logics can be directly set for the exclusive-OR circuit by the prior art according to the characteristics of the flame.

[0036] Since the orange light lags the blue light by 180 degrees, then, if it is in the state of real fire, when the blue light is rising, the orange light must be dropping, and when the orange light is rising, the blue light must be dropping. The rest are false fires. Therefore, Table 1 can be obtained as follows:

[0037] Table 1 Logic Output Table of Exclusive-OR Circuit Module

[0038]

[0039] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An optical flame detection device, characterized in that, It includes a blue light sensor, an orange light sensor, an exclusive-OR circuit module and a main control unit. The blue light sensor is connected to the exclusive-OR circuit module through a first amplification and comparison unit. The orange light sensor is connected to the exclusive-OR circuit module through a second amplification and comparison unit. The first amplification and comparison unit is used to amplify the analog quantity detected by the blue light sensor and compare it with a standard value, and output a digital quantity signal. The second amplification and comparison unit is used to amplify the analog quantity detected by the orange light sensor and compare it with a standard value, and output a digital quantity signal. The exclusive-OR circuit module is connected to the main control unit, and is used to receive the signals of the first amplification and comparison unit and the second amplification and comparison unit and output an exclusive-OR result to the main control unit.

2. An optical flame detection device according to claim 1, characterized in that, The first amplification and comparison unit includes a first amplifier, a first resistor, a second resistor, a third resistor, a fourth resistor and a ninth resistor; The blue light sensor is connected to the third resistor, and the third resistor is connected to the non-inverting input terminal of the first amplifier and the fourth resistor; The inverting input terminal of the first amplifier is connected to the first resistor and the second resistor, and the output terminal of the first amplifier is connected to the exclusive-OR circuit module, the fourth resistor and the fifth resistor.

3. An optical flame detection device according to claim 1, characterized in that, The second amplification and comparison unit includes a second amplifier, a fifth resistor, a sixth resistor, a seventh resistor, an eighth resistor and a tenth resistor; The orange light sensor is connected to the seventh resistor, and the seventh resistor is connected to the non-inverting input terminal of the second amplifier and the eighth resistor; The inverting input terminal of the second amplifier is connected to the fifth resistor and the sixth resistor, and the output terminal of the second amplifier is connected to the exclusive-OR circuit module, the eighth resistor and the tenth resistor.

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