CN216206009U - Flame height detection system for gas appliance and gas appliance - Google Patents
Flame height detection system for gas appliance and gas appliance Download PDFInfo
- Publication number
- CN216206009U CN216206009U CN202122635179.6U CN202122635179U CN216206009U CN 216206009 U CN216206009 U CN 216206009U CN 202122635179 U CN202122635179 U CN 202122635179U CN 216206009 U CN216206009 U CN 216206009U
- Authority
- CN
- China
- Prior art keywords
- flame
- signal
- frequency
- oscillation
- detection system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Control Of Combustion (AREA)
Abstract
The utility model relates to a flame height detection system and a gas appliance. The flame height detection system includes: a measurement oscillation device for outputting a measurement oscillation signal; wherein the frequency of the measurement oscillation signal changes according to a change in inductance of an oscillation coil of the measurement oscillation device; the oscillating coil is wound at a flame nozzle of the gas appliance, so that the inductance of the oscillating coil is changed according to the height change of flame generated by the flame nozzle; and the signal processing device is connected with the measurement oscillation device and used for receiving the measurement oscillation signal and obtaining the height of the flame to be measured according to the frequency of the measurement oscillation signal. The flame height detection system can accurately acquire the height of flame to be detected, so that the accuracy of judging the flame combustion condition can be improved, and the use safety of a gas appliance is ensured.
Description
Technical Field
The utility model relates to the technical field of flame detection, in particular to a flame height detection system for a gas appliance and the gas appliance.
Background
For equipment with a combustion device, such as gas appliances such as a gas stove and a gas water heater, an ion flame signal detection system is generally used for detecting flame so as to judge the flame combustion condition and ensure the use safety of the gas appliances; namely, the gas supply is required to be cut off when no flame exists, and accidents caused by gas leakage are avoided. However, in the conventional technology, it is difficult to accurately determine the combustion condition of the flame by determining whether the flame exists according to the detection result, so that the use safety of the gas appliance is easily not guaranteed.
SUMMERY OF THE UTILITY MODEL
The first technical problem solved by the present invention is to provide a flame height detection system for a gas appliance, which can be used for detecting the flame height.
A second technical problem solved by the present invention is to provide a gas appliance that can be used to detect flame height.
The first technical problem is solved by the following technical scheme:
a flame height detection system for a gas appliance, comprising:
a measurement oscillation device for outputting a measurement oscillation signal; wherein the frequency of the measurement oscillation signal changes according to a change in inductance of an oscillation coil of the measurement oscillation device; the oscillating coil is wound at a flame nozzle of the gas appliance, so that the inductance of the oscillating coil is changed according to the height change of flame generated by the flame nozzle;
and the signal processing device is connected with the measurement oscillation device and used for receiving the measurement oscillation signal and obtaining the height of the flame to be measured according to the frequency of the measurement oscillation signal.
Above-mentioned a flame height detection system for gas apparatus can be according to the accurate height that obtains the flame that awaits measuring of the frequency of measuring oscillation signal, can improve the degree of accuracy of judging the flame burning condition, guarantees gas apparatus's safety in utilization.
In one embodiment, a signal processing apparatus includes: the reference oscillation module is used for outputting a reference oscillation signal with a preset frequency; the frequency mixing module is connected with the measurement oscillation device and the reference oscillation module and is used for receiving the measurement oscillation signal and the reference oscillation signal, performing down-conversion processing on the measurement oscillation signal according to the reference oscillation signal and outputting a down-conversion signal; and the signal processing module is connected with the frequency mixing module and used for receiving the frequency reduction signal and obtaining the height of the flame to be measured according to the frequency of the frequency reduction signal. Therefore, the signal processing module can obtain the height of the flame to be detected according to the frequency of the frequency reduction signal, and the convenience of the flame height detection system is improved.
In one embodiment, the distance between the bottom of the oscillating coil and the flame nozzle is a first preset multiple of the diameter of the oscillating coil; the oscillating coil has a diameter that is a second predetermined multiple of the average diameter of the flame produced by the flame nozzle. Therefore, the embodiment can enable the excitation magnetic field and the induction magnetic field of the oscillating coil to be uniformly distributed, and the reliability of the flame height detection system is improved.
In one embodiment, the flame height detection system further comprises a coil fixing bracket; the coil fixing bracket is used for fixing the oscillating coil above the flame nozzle. Therefore, the coil fixing bracket in the embodiment improves the convenience of the flame height detection system.
In one embodiment, the oscillating coil is wound by silver-plated copper wires, and the surface of the oscillating coil is coated with a refractory material. Therefore, the oscillating coil in the embodiment can prevent the electric leakage caused by the fact that the flame to be detected generated by the flame nozzle in the gas appliance passes through the turns of the oscillating coil, and the stability of the flame height detection system is improved.
In one embodiment, the signal processing module comprises: the detection unit is connected with the frequency mixing module and used for receiving the frequency reduction signal, performing half-wave rectification processing on the frequency reduction signal and outputting a first direct current signal; and the signal processing unit is connected with the detection unit and used for receiving the first direct current signal and obtaining the height of the flame to be measured according to the frequency of the first direct current signal. Thus, the present embodiment can improve the efficiency and convenience of the flame height detection system.
In one embodiment, the signal processing unit includes: the frequency divider is connected with the detection unit and used for receiving the first direct current signal and performing frequency division processing on the first direct current signal to obtain a second direct current signal; and the processor is connected with the frequency divider and used for receiving the second direct current signal and obtaining the height of the flame to be measured according to the frequency of the second direct current signal. Therefore, the embodiment can improve the resolution of the first direct current signal, reduce the cost of the flame height detection system and improve the accuracy of the height of the flame to be detected.
In one embodiment, the reference oscillation module is a quartz crystal oscillator. Therefore, the reference oscillation module in the embodiment can output a stable and reliable reference oscillation signal.
In one embodiment, the measurement oscillator is a capacitive three-point oscillator. Therefore, the measurement oscillation device in the present embodiment can cancel the adverse effect caused by the small change in inductance of the oscillation coil.
The second technical problem is solved by the following technical solutions:
a gas appliance comprising a flame height detection system as described in any one of the above system embodiments.
The gas appliance can accurately obtain the height of the flame to be measured according to the frequency of the measured oscillation signal, so that the accuracy of judging the flame combustion condition can be improved, and the use safety of the gas appliance is ensured.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments or the conventional technologies of the present application, the drawings used in the descriptions of the embodiments or the conventional technologies will be briefly introduced below, it is obvious that the drawings in the following descriptions are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a first schematic block diagram of a flame height detection system in one embodiment;
FIG. 2 is a schematic circuit diagram of an exemplary measurement oscillator device;
FIG. 3 is a second schematic block diagram of a flame height detection system in accordance with an embodiment;
FIG. 4 is a circuit schematic of a reference oscillator module in one embodiment;
FIG. 5 is a schematic circuit diagram of a mixer module according to an embodiment;
FIG. 6 is a third schematic block diagram of a flame height detection system in accordance with an embodiment;
FIG. 7 is a schematic circuit diagram of a detector unit in one embodiment;
FIG. 8 is a fourth schematic block diagram of a flame height detection system in accordance with an embodiment;
fig. 9 is a schematic structural view of a coil fixing bracket in one embodiment.
Detailed Description
To facilitate an understanding of the present application, the present application will now be described more fully with reference to the accompanying drawings. Embodiments of the present application are set forth in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.
It will be understood that, as used herein, the terms "first," "second," and the like may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first resistance may be referred to as a second resistance, and similarly, a second resistance may be referred to as a first resistance, without departing from the scope of the present application. The first resistance and the second resistance are both resistances, but they are not the same resistance.
It is to be understood that "connection" in the following embodiments is to be understood as "electrical connection", "communication connection", and the like if the connected circuits, modules, units, and the like have communication of electrical signals or data with each other.
As used herein, the singular forms "a", "an" and "the" may include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises/comprising," "includes" or "including," etc., specify the presence of stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof.
The flame is a plasma, and a large number of ions in a free state exist in the flame, and the ions are distributed in a disordered manner without an external electric field, so that the overall current is 0. When an electric field is applied to the exterior of the flame, the ions will be distributed orderly along the electric field lines, thereby generating an ion current. The traditional ionic current detection method can only judge whether flame exists or not by detecting the ionic current, so that the flame combustion condition is difficult to accurately judge and the use safety of the gas appliance cannot be well ensured. Because the contact reaction area of the fuel gas and the oxygen directly influences the intensity of combustion, and the position of the flame nozzle of the fuel gas appliance is fixed, the average diameter change of flame generated by the flame nozzle is small, namely the flame combustion condition can be accurately judged by detecting the height of the flame.
In one embodiment, as shown in fig. 1, there is provided a flame height detection system for a gas appliance, the flame height detection system comprising a measurement oscillation device 100 and a signal processing device 200. The measurement oscillator 100 is connected to a signal processor 200.
The measurement oscillation apparatus 100 is an apparatus or a device that can be used to output a measurement oscillation signal. Here, the frequency of the measurement oscillation signal changes in accordance with a change in the inductance of the oscillation coil L1 of the measurement oscillation device 100. In one particular example, the measurement oscillation device 100 may be, but is not limited to, an LC oscillator; wherein the frequency of the measurement oscillation signal generated by the LC oscillator is obtained according to the following expression:
wherein f is the frequency of the measurement oscillation signal; l is an inductance of the oscillation coil L1 of the measurement oscillation device 100; c measures the capacitance of the oscillation device 100. Therefore, it can be understood based on the above expression that the frequency of the measurement oscillation signal will decrease as the inductance of the oscillation coil L1 increases.
And because of that,
wherein f is the frequency of the measurement oscillation signal; l is an inductance of the oscillation coil L1 of the measurement oscillation device 100; c measures the capacitance of the oscillation device 100. Therefore, it can be understood based on the above expression that as the inductance variation of the oscillation coil L1 is smaller, the frequency variation of the measurement oscillation signal is also smaller. When the inductance change of the oscillation coil L1 is small, it is necessary to increase the resolution of flame height detection by increasing the frequency of the measurement oscillation signal. Therefore, the measuring oscillator needs to use a high-frequency LC oscillator to output a high-frequency measuring oscillation signal to counteract the adverse effect of small inductance change of the oscillating coil L1. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
In one embodiment, the measurement oscillator device 100 may be, but is not limited to, a capacitance three-point oscillator, so that the capacitance three-point oscillator generates a high-frequency measurement oscillation signal, thereby canceling out the adverse effect of the small inductance change of the oscillation coil L1. In one specific example, as shown in fig. 2, the measurement oscillation device 100 includes an oscillation coil L1, a capacitor C1, a capacitor C2, an inverted schmitt trigger U1, and an inverted schmitt trigger U2. One end of the oscillating coil L1 is connected with the input end of the reverse-phase Schmitt trigger U1, and the other end of the oscillating coil L1 is connected with the output end of the reverse-phase Schmitt trigger U1; one end of the capacitor C1 is connected with the input end of the reverse Schmitt trigger U1, and the other end is grounded; one end of the capacitor C2 is connected with the output end of the reverse Schmitt trigger U1, and the other end is grounded; the input end of the inverse Schmitt trigger U2 is connected with the output end of the inverse Schmitt trigger U1, and the output end of the inverse Schmitt trigger U2 is connected with the signal processing device 200. In addition, the sizes of the capacitor C1 and the capacitor C2 are determined according to the parasitic capacitance in the inverted schmitt trigger U1. The inverting schmitt trigger U2 has a signal buffering effect.
The frequency of the measurement oscillation signal generated by the measurement oscillation device 100 described above is obtained according to the following expression:
wherein f is the frequency of the measurement oscillation signal; l is1To measure the inductance of the oscillating coil L1 of the oscillating device 100; c1To measure the capacitance C1 of the oscillating device 100; c2To measure the capacitance C2 of the oscillating device 100. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
The oscillation coil L1 of the measuring oscillation device 100 was wound around the flame nozzle of the gas appliance so that the inductance of the oscillation coil L1 was changed in accordance with the change in the height of the flame generated by the flame nozzle. Since the flame produced by the flame nozzle is composed of charged particles, the overall charge is electrically neutral due to the equal values of the positive and negative charges. In the ac magnetic field generated by the oscillating coil L1, the charged particles form a circulating current by the lorentz force of the ac magnetic field, and the direction of the induced magnetic field generated by the circulating current is opposite to the direction of the excitation magnetic field generated by the oscillating coil L1, thereby reducing the magnetic flux of the entire magnetic field of the oscillating coil L1. In terms of the definition of the inductance, the inductance of the oscillating coil L1 is equal to the ratio of the number of flux linkages to the excitation current of the oscillating coil L1, and since the magnetic flux of the entire magnetic field of the oscillating coil L1 is reduced, the number of flux linkages of the oscillating coil L1 is also reduced, resulting in the inductance of the oscillating coil L1 becoming smaller. Therefore, as the flame height increases, more charged particles circulate in the flame, and the induced magnetic field generated against the excitation magnetic field corresponding to the oscillating coil L1 increases, which results in a smaller number of magnetic flux linkages in the oscillating coil L1, and thus the inductance of the oscillating coil L1 decreases. Therefore, the larger the flame height, the smaller the inductance of the oscillation coil L1, that is, the inductance of the oscillation coil L1 can be changed according to the change in the flame height generated by the flame nozzle.
In one specific example, assume that the shape function of the flame produced by the flame nozzle is:
R＝F(z)
wherein z is the height of the first cross section of the flame in the vertical direction, and R is the maximum average radius of the first cross section; the first cross-section may be any cross-section of the flame in the vertical direction.
The flame produced by the flame nozzle is divided into a plurality of concentric loops on a first cross section, and assuming that the loop area of the average flame radius r on the first cross section is A (z, r) and the circumference of the average flame radius r on the first cross section is C (z, r). The flame generated by the flame nozzle was burned in the uniform magnetic field generated by the oscillating coil L1, and the magnetic flux density of the oscillating coil L1 was B.
Therefore, according to maxwell's equation, the relationship between the partial induced electric field generated on the sub-loop having the average radius r on the first cross section of the flame generated from the flame nozzle and the magnetic flux density of the oscillation coil L1 is:
wherein phiC(z,r)Edl is the part of the induced electric field generated on the sub-loop with the average radius r on the first section, BsThe superposition of the induced magnetic fields generated by the flame produced by the flame nozzle on all cross sections except the first cross section. However, the induced magnetic field BsOpposite to the direction of the excitation magnetic field generated by the oscillating coil L1.
Assuming that the average conductivity of the flame over the first cross-section is
Time t, so that the portion generated on the first cross section is separatedThe expression for the sub-current density is:
assuming that the thickness of the first cross section is dz and the loop width in the first cross section is dr, the partial reverse magnetic flux density generated by the sub-loop with the loop width dr in the first cross section of the flame generated by the flame nozzle is:
wherein, mu0Is the magnetic permeability in air; x is the abscissa of the first cross section in the rectangular coordinate system; y is a longitudinal coordinate of the first cross section in a rectangular coordinate system;
the magnetic fields generated by all the cross sections of the flame generated by the flame nozzle are added, and assuming that the flame height is H, the magnetic flux density of the oscillation coil L1 is:
B＝B0+∫H,RdBs
wherein R is the maximum average radius of the first cross-section, B0In the case of the flame nozzle, the magnetic flux density in the coil L1 is oscillated to generate a flame.
Suppose that the area of the oscillation coil L1 is AmThe number of turns of the coil is N.
Therefore, when the flame nozzle is not generating flame, the inductance in the oscillating coil L1 is:
wherein, ImThe current in coil L1 was oscillated when the flame nozzle was not producing a flame.
When the flame nozzle generates a flame with a certain height, the inductance in the oscillating coil L1 is:
where I is the current in the oscillation coil L1 when the flame nozzle is not producing a flame.
From the above analysis, it is found that, as the flame height increases, the induced magnetic field generated in the oscillating coil L1 increases, so that the equivalent inductance of the oscillating coil L1 decreases. Therefore, the flame height can be obtained from the inductance of the oscillation coil L1. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
The signal processing device 200 can receive the measurement oscillation signal output by the measurement oscillation device 100, and can obtain the height of the flame to be measured according to the frequency of the measurement oscillation signal. In one embodiment, the signal processing device 200 can be, but is not limited to, a DSP or an FPGA, so as to improve the resolution of the flame height detection system in the flame height detection process. In addition, the processing of the signal processing apparatus 300 is conventional in the signal processing field, and those skilled in the art can implement the above operations by using conventional technical means according to the above control functions to be implemented.
Based on this, the flame height detection system according to the present embodiment is configured such that the inductance of the oscillation coil L1 is changed according to the change in the flame height generated by the flame nozzle by winding the oscillation coil L1 of the measurement oscillation device 100 around the flame nozzle of the gas appliance; according to the inductance change of the oscillating coil L1, the measuring oscillation device 100 outputs a corresponding measuring oscillation signal; and the signal processing device 200 receives the measurement oscillation signal output by the measurement oscillation device 100, and the height of the flame to be measured is accurately obtained according to the frequency of the measurement oscillation signal, so that the accuracy of judging the combustion condition of the flame can be improved, and the use safety of the gas appliance is ensured.
In one embodiment, as shown in fig. 3, the signal processing apparatus 200 includes a reference oscillation module 210, a mixing module 220, and a signal processing module 230. The mixing module 220 is connected to the measurement oscillator 100 and the reference oscillator 210, and the signal processing module 230 is connected to the mixing module 220.
The reference oscillation module 210 may output a reference oscillation signal of a preset frequency. In one embodiment, the reference oscillation module 210 may be, but is not limited to, a quartz crystal oscillator, so that the reference oscillation module 210 outputs a stable and reliable reference oscillation signal.
In one particular example, as shown in fig. 4, the reference oscillation module 210 includes a quartz resonator X1, a resistor R1, a capacitor C3, a capacitor C4, an inverted schmitt trigger U3, and an inverted schmitt trigger U4. One end of the quartz resonator X1 is connected with the input end of the inverse Schmitt trigger U3 and the first end of the resistor R1, and the other end is connected with the output end of the inverse Schmitt trigger U3 and the second end of the resistor R1; one end of the capacitor C3 is connected with the input end of the reverse Schmitt trigger U3, and the other end is grounded; one end of the capacitor C4 is connected with the output end of the reverse Schmitt trigger U3, and the other end is grounded; the input end of the inverse Schmitt trigger U4 is connected with the output end of the inverse Schmitt trigger U3, and the output end of the inverse Schmitt trigger U4 is connected with the frequency mixing module 220. In addition, the inverting schmitt trigger U4 has a signal buffering function. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
The mixing module 220 may receive the measurement oscillation signal output by the measurement oscillation device 100 and the reference oscillation signal output by the reference oscillation module 210, perform down-conversion processing on the measurement oscillation signal according to the reference oscillation signal, and output a down-converted signal.
In one embodiment, the mixing module 220 may be, but is not limited to being, a mixer. The frequency mixer can add or subtract the measurement oscillation signal output by the measurement oscillation device 100 and the reference oscillation signal output by the reference oscillation module 210 based on its own characteristics, and because the output filter of the frequency mixer cannot separate the image frequency and the intermodulation frequency, the preset frequency of the reference oscillation signal output by the reference oscillation module 210 needs to be set to be 10MHz different from the measurement oscillation signal to avoid the frequency pulling effect of the frequency mixer.
In a specific example, the mixing module 220 adopts a circuit structure as shown in fig. 5, the core element of the mixing module 220 includes a frequency conversion tube Q1, and the resistor R6 isThe frequency converter tube Q1 operates to provide a bias current. Collector current I of frequency conversion tube Q1cmAnd a base voltage signal U generated by a filter composed of a capacitor C5, a resistor R2 and a resistor R4 from a signal inputted from the port "MX _ iabAnd an emitter U generated by a signal inputted from the MX _ ib through a filter composed of a capacitor C6, a resistor R3 and a resistor R5eThe relationship between is developed by taylor series:
wherein, UbAnd UeAre square wave signals and are expressed by using a fourier series expansion as follows:
neglecting the collector current I of the frequency conversion tube Q1cmHigher-order terms of order 3 or more in Fourier series expansion, and UbAnd UeTaking only the fundamental wave in the Fourier series expansion to obtain:
therefore, it can be known from the above analysis that the harmonic included in the down-converted signal outputted from the mixing module 220 is very complex, wherein the harmonic is
Harmonics required for flame height detection. Therefore, the frequency is tuned to ω using the resonant tank consisting of the primary inductor of the coupling transformer T1 and the resonant capacitor C7 at the collector of the frequency converter Q1b-ωeThe harmonic wave required by the flame height detection system can be returned through resonanceThe circuit realizes the extraction of the target frequency in the composite signal. If the numbers of turns of 1-2, 3-4 and 4-5 of the coupling transformer T1 are the same, the inductance of the coil 3-5 is LpTherefore, the impedance of the resonant circuit formed by the capacitor C7, the resistor R7 and the primary winding 3-5 of the coupling transformer T1 has the expression:
the output gain of the mixer module 220 is proportional to the impedance of the resonant tank formed by the capacitor C7, the resistor R7 and the primary winding 3-5 of the transformer T1. Mixing module 220 input signal UbOr UeFrom the measurement oscillation device 100 and the reference oscillation module 210, respectively, so ωb-ωeNot a fixed value but fluctuates within a small range. Resistor R7 provides some bandwidth for the mixer output tank and removes other unwanted harmonics. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
The signal processing module 230 may receive the down-converted signal output by the frequency mixing module 220, and obtain the height of the flame to be measured according to the frequency of the down-converted signal. In addition, the processing of the signal processing module 230 is conventional in the signal processing field, and those skilled in the art can implement the above operations by using conventional technical means according to the above control functions that need to be implemented.
In this embodiment, the mixing module 220 performs down-conversion processing on the measurement oscillating signal output by the measurement oscillating device 100 according to the reference oscillating signal output by the reference oscillating module 210, and outputs a down-converted signal with a frequency lower than that of the measurement oscillating signal, so that the signal processing module 230 obtains the height of the flame to be detected according to the frequency of the down-converted signal, thereby improving the convenience of the flame height detection system.
In one embodiment, as shown in fig. 6, the signal processing module 230 includes a wave detecting unit 231 and a signal processing unit 232; the detecting unit 231 is connected to the mixing module 220, and the signal processing unit 232 is connected to the detecting unit 231.
The detecting unit 231 may receive the frequency-reduced signal output by the frequency mixing module 220, perform half-wave processing on the frequency-reduced signal, and output a first direct current signal. In one embodiment, the detection unit 231 may be, but is not limited to, a detector.
In a specific example, as shown in fig. 7, the wave detecting unit 231 includes a resistor R12, a diode D1, and a diode D2; the first end of the resistor R12 is connected to the mixing module 231 and the anode of the diode D1, and is configured to receive the down-converted signal output by the mixing module; the second terminal of the resistor R12 is connected to the cathode of the diode D1, the cathode of the diode D2 and the signal processing unit 232, and the anode of the diode D2 is grounded.
The signal processing unit 232 may receive the first dc signal output by the detection unit, and obtain the height of the flame to be measured according to the frequency of the first dc signal. In addition, the processing of the signal processing unit 232 is conventional technical means in the signal processing field, and the person skilled in the art can implement the above operations by using conventional technical means according to the above control functions that need to be implemented.
In this embodiment, the detection unit 231 performs half-wave rectification processing on the down-converted signal output by the mixing module 220 to output a first direct current signal; therefore, the signal processing unit 232 only needs to count the number of half-waves in the first dc signal, and the frequency of the first dc signal can be obtained; meanwhile, the signal processing unit 232 obtains the height of the flame to be detected according to the frequency of the first direct current signal, so that the efficiency and the convenience of the flame height detection system are improved.
In one embodiment, as shown in fig. 8, the signal processing unit 232 includes a frequency divider 232a and a processor 232 b; the frequency divider 232a is connected to the detection unit 231, and the processor 232b is connected to the frequency divider 232 a.
The frequency divider 232a may receive the first dc signal output by the detection unit 231, and perform frequency division processing on the first dc signal to obtain a second dc signal. In a specific example, since the mixing module 220 performs down-conversion processing on the measurement oscillation signal output by the measurement oscillation device 100, the mixing module 220The frequency of the output down-converted signal is still high, and the frequency mixing module 220 cannot increase the variance of the period of the measurement oscillation signal, which results in insufficient resolution of the measurement oscillation signal, so the signal processing unit 232 is provided with a frequency division chip CD 4060. The first dc signal output from the detection unit 231 is divided by two for 14 times by the frequency division chip CD4060, and the first dc signal with the period T is changed into the first dc signal with the period 214T, a second dc signal. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
The processor 232b may receive the second dc signal output by the frequency divider 232a, and obtain the height of the flame to be measured according to the frequency of the second dc signal. In a specific example, the processor 232b may be but is not limited to a single chip microcomputer, the single chip microcomputer may receive the second direct current signal through an external start pin, start a timer to count after detecting a pulse edge of the second direct current signal, and stop counting until a next pulse edge arrives, so as to obtain a frequency of the second direct current signal; the singlechip can obtain the height of the flame to be measured through the frequency of the second direct current signal. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein. In addition, the processing of the processor 232b is conventional in the signal processing field, and those skilled in the art can implement the above operations by using conventional technical means according to the above control functions to be implemented.
In this embodiment, the frequency divider 232a divides the first dc signal output by the detection unit 231 to obtain a second dc signal, so as to amplify the variance of the signal period of the first dc signal, thereby improving the resolution of the first dc signal and reducing the frequency of the first dc signal; the low-frequency processor 232b can be directly adopted to obtain the accurate height of the flame to be detected according to the frequency of the second direct current signal, so that the cost of the flame height detection system is reduced, and the accuracy of the height of the flame to be detected is improved.
In one embodiment, as shown in fig. 9, the distance H between the bottom of the oscillating coil L1 and the flame nozzle of the gas appliance is a first preset multiple of the diameter D of the oscillating coil L1; the diameter D of the oscillating coil L1 is a second preset multiple of the average diameter of the flame generated by the flame nozzle of the gas appliance;
in one specific example, the second preset multiple may be, but is not limited to, 1.3; the distance H between the bottom of the oscillating coil L1 and the flame nozzle of the gas appliance is obtained based on the following expression:
the above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
In the embodiment, the distance H between the bottom of the oscillating coil L1 and the flame nozzle of the gas appliance is set to be a first preset multiple of the diameter D of the oscillating coil L1, so that the phenomenon that the oscillation of the measuring and oscillating device 100 is stopped due to the fact that the oscillating coil L1 is too close to the flame nozzle made of metal is avoided; the diameter D of the oscillating coil L1 is set to be the second preset multiple of the average diameter of the flame generated by the flame nozzle of the gas appliance, so that the flame generated by the flame nozzle is ensured to be sleeved in the oscillating coil L1 as far as possible, the excitation magnetic field and the induction magnetic field of the oscillating coil L1 can be uniformly distributed, and the reliability of the flame height detection system is improved.
In one embodiment, the flame height detection system further comprises a coil fixing bracket 300; wherein, the coil fixing bracket 300 is used for fixing the oscillating coil L1 above a flame nozzle of a gas appliance; the convenience of the flame height detection system is also improved.
In one embodiment, the coil fixing bracket 300 is made of a ceramic material, so that the insulation and high temperature resistance of the coil fixing bracket are improved, the oscillation coil L1 is prevented from being affected, and the overall service life of the flame height detection system is prolonged.
In a specific example, as shown in fig. 9, the coil fixing bracket 300 is an L-shaped fixing bracket, and the vertical edge of the coil fixing bracket 300 is provided with a first through hole 310 and a second through hole 320, so that both ends of the oscillating coil L1 are fixed on the coil fixing bracket 300 through the first through hole 310 and the second through hole 320, respectively; meanwhile, the bottom side of the coil fixing bracket 300 is provided with a third through hole 330, and the third through hole 330 is used for fixing the coil fixing bracket 300 on the cabinet 500 of the gas appliance by fastening the bolt 400. The above is only a specific example, and the practical application can be flexibly set according to requirements, and is not limited herein.
In one embodiment, the oscillating coil L1 is made of silver-plated copper wire, and the surface of the oscillating coil L1 is coated with a refractory material, so that electric leakage caused by the fact that the flame to be detected generated by the flame nozzle in the gas appliance passes through turns of the oscillating coil is prevented, and the stability of the flame height detection system is improved.
In one embodiment, a gas appliance is provided that includes a flame height detection system of any of the above system embodiments. The gas appliance can accurately obtain the height of the flame to be measured according to the frequency of the measured oscillation signal, so that the accuracy of judging the flame combustion condition can be improved, and the use safety of the gas appliance is ensured.
In the description herein, references to the description of "some embodiments," "other embodiments," "desired embodiments," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the utility model. In this specification, a schematic description of the above terminology may not necessarily refer to the same embodiment or example.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the utility model. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (10)
1. A flame height detection system for a gas appliance, comprising:
a measurement oscillation device (100) for outputting a measurement oscillation signal; wherein the frequency of the measurement oscillating signal varies in accordance with a variation in inductance of an oscillating coil of the measurement oscillating device (100); the oscillating coil is wound at a flame nozzle of a gas appliance, so that the inductance of the oscillating coil is changed according to the height change of flame generated by the flame nozzle;
and the signal processing device (200) is connected with the measurement oscillation device (100) and is used for receiving the measurement oscillation signal and obtaining the height of the flame to be measured according to the frequency of the measurement oscillation signal.
2. Flame height detection system according to claim 1, characterized in that said signal processing means (200) comprise:
a reference oscillation module (210) for outputting a reference oscillation signal of a preset frequency;
the frequency mixing module (220) is connected with the measurement oscillation device (100) and the reference oscillation module (210) and is used for receiving the measurement oscillation signal and the reference oscillation signal, performing down-conversion processing on the measurement oscillation signal according to the reference oscillation signal and outputting a down-converted signal;
and the signal processing module (230) is connected with the frequency mixing module (220) and is used for receiving the frequency reduction signal and obtaining the height of the flame to be measured according to the frequency of the frequency reduction signal.
3. The flame height detection system of claim 1, wherein a bottom of the oscillating coil is a first predetermined multiple of a diameter of the oscillating coil from the flame nozzle; the diameter of the oscillating coil is a second preset multiple of the average diameter of the flame generated by the flame nozzle.
4. The flame height detection system of claim 1, further comprising a coil fixing bracket (300); the coil fixing bracket (300) is used for fixing the oscillation coil above the flame nozzle.
5. The flame height detection system of claim 1, wherein the oscillating coil is wound with silver-plated copper wire, and a surface of the oscillating coil is coated with a refractory material.
6. The flame height detection system of claim 2, wherein the signal processing module (230) comprises:
the detection unit (231) is connected with the frequency mixing module (220) and is used for receiving the frequency reducing signal, performing half-wave rectification processing on the frequency reducing signal and outputting a first direct current signal;
and the signal processing unit (232) is connected with the wave detection unit (231) and is used for receiving the first direct current signal and obtaining the height of the flame to be measured according to the frequency of the first direct current signal.
7. The flame height detection system of claim 6, wherein the signal processing unit (232) comprises:
the frequency divider (232a) is connected with the detection unit (231) and is used for receiving the first direct current signal and dividing the frequency of the first direct current signal to obtain a second direct current signal;
and the processor (232b) is connected with the frequency divider (232a) and is used for receiving the second direct current signal and obtaining the height of the flame to be measured according to the frequency of the second direct current signal.
8. The flame height detection system of claim 2, wherein the reference oscillation module (210) is a quartz crystal oscillator.
9. Flame height detection system according to claim 1, characterized in that the measuring oscillation device (100) is a capacitive three-point oscillator.
10. A gas appliance comprising a flame height detection system according to any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122635179.6U CN216206009U (en) | 2021-10-29 | 2021-10-29 | Flame height detection system for gas appliance and gas appliance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122635179.6U CN216206009U (en) | 2021-10-29 | 2021-10-29 | Flame height detection system for gas appliance and gas appliance |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN216206009U true CN216206009U (en) | 2022-04-05 |
Family
ID=80896617
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122635179.6U Active CN216206009U (en) | 2021-10-29 | 2021-10-29 | Flame height detection system for gas appliance and gas appliance |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN216206009U (en) |
-
2021
- 2021-10-29 CN CN202122635179.6U patent/CN216206009U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Godyak et al. | Experimental setup and electrical characteristics of an inductively coupled plasma | |
| US7212930B2 (en) | Method and apparatus for phase determination | |
| US20160064952A1 (en) | Power transmission device and wireless power transmission system | |
| JP2017034972A (en) | Foreign matter detection device, radio power transmission device and radio power transmission system | |
| JP2019522784A (en) | Non-contact type electrical conductivity and non-conductor dielectric constant change measurement device using RF signal | |
| CN113050014B (en) | Sensitivity coefficient calibration method and system for low-frequency pulse magnetic field sensor | |
| CN216206009U (en) | Flame height detection system for gas appliance and gas appliance | |
| Abd Aziz et al. | A Study on wireless power transfer using tesla coil technique | |
| CN106843366B (en) | A kind of magnetic field adjusting device and method | |
| CN114046725A (en) | Flame height detection system for gas appliance and gas appliance | |
| CN102879640A (en) | Electromagnetic coupling resonance coil parameter measurement system | |
| US6737617B1 (en) | Methods and apparatus for a signal distortion based detection system | |
| Zhou et al. | A new metal detection method based on balanced coil for mobile phone wireless charging system | |
| CN213686924U (en) | Isolated flame detection circuit and gas utensil | |
| CN109061260A (en) | A method of preventing strong magnetic stealing | |
| Coumou et al. | Time-Resolved Electron Density Measurement Characterization of E–H-Modes for Inductively Coupled Plasma Instabilities | |
| Diehl et al. | The electromagnetic modes of a helical resonator | |
| CN207945786U (en) | Internal resistance of cell detection circuit and energy-storage battery air-conditioning | |
| Spang et al. | Relativistic magnetron development for use in a lightweight, repetitively pulsed, portable HPM transmitter | |
| Chen | Modern uses of Langmuir probes | |
| RU2371714C2 (en) | Eddy current control method and device to this end | |
| CN113654678B (en) | Heating temperature measurement circuit, temperature measurement method thereof, cooking device and storage medium | |
| Tao et al. | Design, simulation and test of a double differential D-dot overvoltage sensor | |
| US2302369A (en) | Oscillation generation system | |
| CN209418263U (en) | A kind of integrated inductor and protective device of leakage current |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |