A fault detection method for a gas stove and a gas stove

Abstract

The present invention discloses a fault detection method for a gas stove and a gas stove having the fault detection ability. After the gas valve of the gas stove is operated to be opened, the actual opening degree of the gas valve is collected, and the alarm threshold is calculated and updated according to the collected actual opening degree of the gas valve; the actual flame temperature of the burner is collected, and when the actual flame temperature is less than the alarm threshold, a fault alarm is output. The fault detection method of this embodiment calculates the alarm threshold according to the actual opening degree of the valve and judges the fault alarm according to the alarm threshold, which can not only ensure the rapid detection of the fault alarm, but also avoid misjudgment and improve the accuracy of fault detection and alarm.

Description

Technical Field

[0001] The present invention relates to the technical field of gas stoves, and particularly to a method for detecting faults of a gas stove and a gas stove having the fault detection ability. Background Art

[0002] The commonly used flame detection method for current stoves is: judging whether there is a flame by detecting a thermocouple fixed at the inner ring position of the burner head. When there is a flame, the temperature of the thermocouple rises and the output voltage increases; when there is no flame, the temperature of the thermocouple drops and the output voltage decreases. Therefore, the detection of whether the flame goes out can be realized by detecting the magnitude of the voltage output by the thermocouple, and then the judgment of two faults of accidental flameout and failed flameout can be completed.

[0003] Currently, when detecting the above two faults, a method of comparing the output voltage of the thermocouple with a preset fixed threshold is generally used for judgment. When the electromagnetic valve is opened to control the stove to work during combustion, if the output voltage of the thermocouple does not reach the set threshold, it is considered that an accidental flameout fault occurs; after the electromagnetic valve is closed to control the stove to go out, if the output voltage of the thermocouple exceeds the set threshold, it is considered that a failed flameout fault occurs.

[0004] However, this fault detection method has a defect: the temperature of the thermocouple is related to the firepower. When the alarm threshold set for the accidental flameout fault is large, if the firepower is adjusted to the minimum, there may be false alarms; if the alarm threshold for accidental flameout is set small, when an accidental flameout occurs during high-fire combustion, the delay in triggering the alarm is relatively long. Similarly, when the alarm threshold set for the failed flameout fault is large, if the electromagnetic valve is not successfully closed and the firepower is small at this time, the alarm will not be triggered; if the alarm threshold for failed flameout is set small, even if the stove is normally turned off, it may be misjudged because the temperature of the thermocouple does not drop in time due to the high firepower before turning off the stove. Summary of the Invention

[0005] The present invention provides a method for detecting faults of a gas stove, which improves the accuracy of fault detection.

[0006] To achieve the above technical purpose, the present invention is realized by the following technical solutions:

[0007] A method for detecting faults of a gas stove includes:

[0008] Operate the gas valve of the gas stove to open,

[0009] Collect the actual opening degree of the gas valve, and calculate and update the alarm threshold according to the collected actual opening degree of the gas valve;

[0010] Collect the actual flame temperature of the cooking range. When the actual flame temperature is less than the alarm threshold, output a fault alarm.

[0011] Furthermore, set a first sampling period. Within each first sampling period, collect the actual opening degree of the gas valve. Based on the n actual opening degrees of the gas valve continuously collected, calculate and update the alarm threshold. Set a second sampling period. Within each second sampling period, collect the actual flame temperature of the cooking range and compare it with the alarm threshold. When the actual flame temperature is less than the alarm threshold, output a fault alarm. The first sampling period is greater than the second sampling period.

[0012] Even further, collect the actual flame temperature of the cooking range through a temperature detection device and output a voltage detection signal. Generate a voltage sampling value based on the voltage detection signal, and the voltage sampling value reflects the actual flame temperature of the cooking range. The alarm threshold is the voltage threshold corresponding to the normal flame temperature at the actual opening degree of the gas valve.

[0013] The process of collecting the actual opening degree of the gas valve, calculating and updating the alarm threshold based on the collected actual opening degree of the gas valve includes:

[0014] Collect the actual opening degree B of the gas valve.

[0015] Obtain the ideal voltage detection value according to the preset correspondence between the valve opening degree and the ideal voltage detection value.

[0016] Calculate and update the alarm threshold according to the obtained ideal voltage detection value.

[0017] Even more further, after collecting the actual opening degree B of the gas valve, first correct the actual opening degree B of the gas valve to obtain the corrected valve opening degree A i ; then obtain the ideal voltage detection value corresponding to the valve opening degree A i according to the preset correspondence between the valve opening degree and the ideal voltage detection value;

[0018] The correction formula is:

[0019]

[0020] where B ∈ [0, 1]; when B = 1, it means the valve is fully open and the valve is in the maximum fire position; when B = 0.2, the valve is in the minimum fire position; when B = 0, it means the valve is fully closed.

[0021] Even more, the correspondence between the valve opening degree and the ideal voltage detection value is:

[0022]

[0023] where Ui is the ideal voltage detection value, U max is the ideal voltage detection value when the valve is in the maximum fire position, U min is the ideal voltage detection value when the valve is in the minimum fire position.

[0024] Further, the alarm threshold is calculated and updated according to the obtained ideal voltage detection value, and the calculation formula is:

[0025]

[0026] where U alm is the alarm threshold, K is a constant, 0.7 ≤ K ≤ 0.9; W i is the weight of U i ; the sum of weights is 1.

[0027] Furthermore, when it is continuously determined m times that the actual flame temperature of the burner head collected is less than the alarm threshold, a fault alarm is output; where m > 1.

[0028] Even further, the fault detection method further includes: after operating the gas valve to close, delaying for a set time, collecting the actual flame temperature of the burner head, and when the actual flame temperature is greater than a preset fixed threshold, outputting a fault alarm.

[0029] Still further, when it is continuously determined M times that the actual flame temperature of the burner head collected is greater than the fixed threshold, a fault alarm is output; where M > 1.

[0030] A gas stove, comprising:

[0031] A valve opening acquisition device for collecting the actual opening of the gas valve;

[0032] A temperature detection device for collecting the actual flame temperature of the burner head;

[0033] A controller for, after operating the gas valve of the gas stove to open, controlling the valve opening acquisition device to collect the actual opening of the gas valve, calculating and updating the alarm threshold according to the collected actual opening of the gas valve; controlling the temperature detection device to collect the actual flame temperature of the burner head, and outputting a fault alarm when the actual flame temperature is less than the alarm threshold.

[0034] Further, the temperature detection device is a thermocouple, the thermocouple collects the actual flame temperature of the burner head, outputs a voltage detection signal to the controller, and the controller generates a voltage sampling value according to the voltage detection signal.

[0035] Even further, the controller includes:

[0036] A correction module, configured to receive the actual opening B of the gas valve collected by the gas valve opening acquisition device, and correct the actual opening B of the gas valve to obtain the corrected valve opening A i ;

[0037] A detection value calculation module, configured to obtain the valve opening A according to the corresponding relationship between the preset valve opening and the ideal voltage detection value i The corresponding ideal voltage detection value;

[0038] A threshold calculation module, configured to calculate and update the alarm threshold according to the obtained ideal voltage detection value;

[0039] An AD conversion module, configured to receive the voltage detection signal output by the temperature detection device, and perform analog-to-digital conversion on the received voltage detection signal to generate a voltage sampling value;

[0040] A judgment and alarm module, configured to output a fault alarm when the voltage sampling value is less than the alarm threshold.

[0041] Compared with the prior art, the advantages and positive effects of the present invention are: the fault detection method for a gas stove and the gas stove having the fault detection ability of the present invention collect the actual opening of the gas valve after the gas valve of the gas stove is opened, calculate and update the alarm threshold according to the collected actual opening of the gas valve; collect the actual flame temperature of the burner head, and output a fault alarm when the actual flame temperature is less than the alarm threshold. The fault detection method of this embodiment calculates the alarm threshold according to the actual valve opening and judges the fault alarm according to the alarm threshold, which can not only ensure the rapid detection of the fault alarm, but also avoid misjudgment, and improve the accuracy of fault detection and alarm.

[0042] After reading the specific embodiments of the present invention in conjunction with the drawings, other features and advantages of the present invention will become clearer. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0044] Figure 1 is a flowchart of an embodiment of the fault detection method for a gas stove proposed by the present invention;

[0045] Figure 2 is Figure 1 a flowchart of an embodiment of step S1 in;

[0046] Figure 3 It is a structural block diagram of an embodiment of the gas stove proposed by the present invention. Specific Embodiments

[0047] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0048] It should be noted that in the description of the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0049] Embodiment 1

[0050] The fault detection method for the gas stove in this embodiment provides a fast and reliable method for judging accidental flameout and failed flameout of the stove. Accidental flameout refers to the situation where no flame is detected during normal combustion; failed flameout means that when some stoves detect problems such as dry burning, they will control the gas valve to close, but the valve fails to close successfully. Below, with reference to specific drawings, the fault detection method of this embodiment will be described in detail.

[0051] The fault detection method for the gas stove in this embodiment, after the gas valve of the gas stove is opened, the following steps are executed, as shown in Figure 1 shown.

[0052] Step S1: Collect the actual opening degree of the gas valve, and calculate and update the alarm threshold according to the collected actual opening degree of the gas valve. The alarm threshold directly or indirectly reflects the normal flame temperature at the collected actual opening degree of the gas valve.

[0053] Step S2: Collect the actual flame temperature of the burner head, and output a fault alarm when the actual flame temperature is less than the alarm threshold.

[0054] When the collected actual flame temperature of the burner head is less than the alarm threshold, it indicates that the stove is not burning normally and accidental flameout may occur. At this time, an alarm is triggered to prompt the user. The alarm methods include sound and light alarm, text message alarm, network alarm, etc. At the same time of the alarm, the gas source can also be directly cut off to avoid accidents.

[0055] The fault detection method of this embodiment calculates and updates the alarm threshold according to the collected actual opening degree of the gas valve, and judges the fault according to the alarm threshold, which can not only ensure fast fault detection, but also avoid misjudgment, and improve the accuracy of fault detection and alarm.

[0056] In order to facilitate the acquisition of the actual flame temperature of the cooking hob, the calculation and update of the alarm threshold, the fault judgment, etc., a temperature detection device is installed on the cooking hob. The actual flame temperature of the cooking hob is collected through the temperature detection device. The temperature detection device outputs a voltage detection signal and sends it to the controller of the gas stove. The controller performs analog-to-digital conversion on the received voltage detection signal to generate a voltage sampling value, and the voltage sampling value reflects the actual flame temperature of the cooking hob. Correspondingly, the alarm threshold is the voltage threshold corresponding to the normal flame temperature at the actual opening degree of the gas valve collected; when the voltage sampling value is less than the voltage threshold, a fault alarm is output. In this embodiment, the temperature detection device is preferably a thermocouple, and the thermocouple collects the actual flame temperature of the cooking hob and outputs a voltage detection signal.

[0057] In this embodiment, a first sampling period is set. Within each first sampling period, the actual opening degree of the gas valve is collected. According to the continuously collected n actual opening degrees of the gas valve, the alarm threshold is calculated and updated. A second sampling period is set. Within each second sampling period, the actual flame temperature of the cooking hob is collected and compared with the alarm threshold. When the actual flame temperature is less than the alarm threshold, a fault alarm is output. The first sampling period is greater than the second sampling period. Therefore, the frequency of calculating and updating the alarm threshold is less than the frequency of collecting the actual flame temperature of the cooking hob (i.e., the frequency of performing fault judgment), avoiding resource waste. This is because if the frequency of calculating the alarm threshold is high and the frequency of collecting the actual flame temperature of the cooking hob is low, it is possible that the calculated alarm threshold has not been used yet and is updated again, resulting in waste of computing resources. Therefore, in this embodiment, the frequency of calculating and updating the alarm threshold is less than the frequency of collecting the actual flame temperature of the cooking hob. It is possible that the same alarm threshold is used for two alarm judgments to make the most of the already calculated threshold and avoid resource waste.

[0058] As a preferred design scheme of this embodiment, step S1 specifically includes the following steps, see Figure 2 as shown.

[0059] S11. Collect the actual opening degree B of the gas valve.

[0060] For the valve of the gas stove, generally the middle position is the maximum firepower position, and adjusting in both directions will reduce the firepower. For some valves, the initial position (such as 0°) and the maximum firepower position (such as 90°) form a 90-degree angle, and the maximum firepower position (such as 90°) and the final position (such as 180°) form a 90-degree angle; for some valves, the initial position (such as 0°) and the maximum firepower position (such as 90°) form a 90-degree angle, but the maximum firepower position (such as 90°) and the final position (such as 210°) form a 120-degree angle, or even larger. The adjustment between the initial position and the maximum firepower position is called: forward adjustment; the adjustment between the maximum firepower position and the final position is called: reverse adjustment.

[0061] The valve opening is a quantity approximately representing the firepower. When the valve is in the initial position, it is fully closed and there is no firepower. At this time, the valve opening is the smallest, denoted as B zero = 0; when the valve is in the maximum firepower position, it is fully open and the firepower is the largest. At this time, the valve opening is the largest, denoted as B max = 1; when the valve is in the final position, the valve will not be fully closed. At this time, the firepower is very small, which is the minimum firepower. At this time, the valve opening is the minimum allowable opening, denoted as B min , for example, B min = 0.2. The actual valve opening is denoted as B. When B = 0, it means the valve is fully closed; when B = 1, it means the valve is fully open

[0062] An annular slide rheostat linked coaxially with the valve is used to detect the valve opening. It is required that the resistance value of the slide rheostat changes uniformly as it slides. The method of measuring the resistance value of the slide rheostat can refer to the existing public technologies. For example, by dividing the voltage with a fixed resistor and detecting the voltage after voltage division to calculate the resistance value. Assume that the measured resistance value of the slide rheostat is R, the resistance value of the slide rheostat when the valve is in the initial position is R1, the resistance value of the slide rheostat when the valve is in the maximum firepower position is R2, and the resistance value of the slide rheostat when the valve is in the final position (i.e., the minimum firepower position) is R3. Then for a continuous slide rheostat, there must be: R1 > R2 > R3, or R3 > R2 > R1

[0063] When adjusting between the initial position and the maximum firepower position, that is, during forward adjustment, the calculation formula for the actual valve opening B of the valve is:

[0064]

[0065] If the calculated B is less than 0.2, then let B = 0.2

[0066] When adjusting between the maximum firepower position and the minimum firepower position, that is, during reverse adjustment, the calculation formula for the actual valve opening B of the valve is:

[0067]

[0068] By detecting the resistance value R of the slide rheostat, the actual opening B of the gas valve can be obtained. Of course, in addition to calculating the actual opening of the valve according to the resistance value of the slide changer as described above, the actual opening of the gas valve can also be obtained through other devices such as sensors

[0069] S12. Correct the actually measured opening B of the gas valve to obtain the corrected valve opening A i .

[0070] After the firepower of the stove changes, the change in the temperature of the thermocouple (or the voltage output signal) lags. Moreover, the temperature at the thermocouple end is the same within a certain range of relatively high firepower. Since the actual opening B of the valve and the actually measured thermocouple temperature are not linear, it is necessary to correct the actually measured valve opening B collected to improve the accuracy of the ideal voltage detection value obtained in the subsequent steps.

[0071] According to the correction formula

[0072]

[0073] correct the actual valve opening B to obtain the corrected valve opening A i , so as to eliminate the non-linear influence as much as possible, making the ideal voltage detection value generated by the ideal voltage detection signal of the subsequent temperature detection device linearly related to the valve opening A i and improving the accuracy of the ideal voltage detection value obtained in the subsequent steps. Among them, B ∈ [0, 1]; when B = 1, it means the valve is fully open and the valve is at the maximum firepower position; when B = 0.2, the valve is at the minimum firepower position; when B = 0, it means the valve is fully closed.

[0074] Of course, S12 can also be deleted, that is, the collected valve opening is not corrected. Although there is a certain error in the finally obtained ideal detection value, time is saved.

[0075] S13. Obtain the valve opening A corresponding to the ideal voltage detection value according to the preset correspondence between the valve opening and the ideal voltage detection value i and the corresponding ideal voltage detection value.

[0076] The ideal voltage detection signal output by the temperature detection device is an analog signal. After analog-to-digital conversion, a digital signal is generated, that is, the ideal voltage detection value. Therefore, the correspondence between the valve opening and the ideal voltage detection value specifically refers to the correspondence between the valve opening and the ideal voltage detection value generated by the ideal voltage detection signal output by the temperature detection device.

[0077] The correspondence between the valve opening and the ideal voltage detection value is:

[0078]

[0079] Among them, A i is the corrected valve opening, and U i is the ideal voltage detection value; U max is the ideal voltage detection value when the valve is at the maximum firepower position. At this time, the valve opening is the maximum value B max , that is, the valve is fully open and at the maximum firepower position; U minIt is the ideal voltage detection value when the valve is in the minimum firepower position. At this time, the valve opening is the minimum allowable opening B min , the valve is in the minimum firepower position.

[0080] This formula indicates the ideal voltage detection value U generated by the ideal voltage detection signal output by the temperature detection device i and the valve opening A i The linear relationship between them. Through this formula, the ideal voltage detection value can be conveniently and accurately obtained, which is simple and convenient with a small amount of calculation.

[0081] S14. Calculate and update the alarm threshold according to the obtained ideal voltage detection value.

[0082] Due to the temperature detection device, especially the thermocouple, when the stove firepower changes, the change of the temperature (or voltage output signal) of the thermocouple is lagged. Therefore, it is necessary to consider the ideal voltage detection value obtained in the historical sampling period, and it is necessary to calculate and update the alarm threshold according to the latest obtained n ideal voltage detection values. Therefore, in this embodiment, in order to further improve the accuracy of the alarm threshold, the specific steps of S14 include: judging whether the total number of the obtained ideal voltage detection values is ≥n. When the total number of the obtained ideal voltage detection values is ≥n, calculate and update the alarm threshold according to the latest obtained n ideal voltage detection values; where n≥1.

[0083] If the total number of the obtained ideal voltage detection values is less than n, wait for the next first sampling period, continue to collect the actual opening of the gas valve, obtain the ideal voltage detection value, and calculate and update the alarm threshold according to the latest obtained n ideal voltage detection values until the total number of the obtained ideal voltage detection values is ≥n; then execute S2.

[0084] The alarm threshold calculation formula is:

[0085]

[0086] Among them, U alm is the alarm threshold, K is a constant, 0.7≤K≤0.9; U i is the ideal voltage detection value; W i is the weight of U i ; the sum of the weights is 1. In this embodiment, 0.7≤K≤0.9. If the value of K is too large, it will cause U alm to be too large, which is likely to cause untimely alarm; if the value of K is too small, it will cause U alm to be too small, which is likely to cause frequent alarms and a high misjudgment rate. Therefore, K is selected in the above value range, which can not only ensure fast and timely alarm but also avoid misjudgment. As a preferred solution, K = 0.8.

[0087] When n > 1, when the gas valve is just opened, it may not have obtained n ideal voltage detection values yet. At this time, it can wait until n ideal voltage detection values are obtained, and then calculate the alarm threshold for fault judgment. In subsequent sampling periods, after each new ideal voltage detection value is obtained, calculate the alarm threshold according to the latest n ideal voltage detection values in chronological order. Among them, the n weights remain unchanged and are assigned to the n ideal voltage detection values according to chronological order.

[0088] This formula comprehensively considers n ideal voltage detection values and weights to calculate the alarm threshold, and can obtain a relatively accurate and reasonable alarm threshold, providing an accurate and reasonable judgment basis for subsequent fault judgment and improving the accuracy of fault judgment.

[0089] Assume n = 10, and the 10 ideal voltage detection values obtained latest in chronological order are: U1, U2, U3, U4, U5, U6, U7, U8, U9, U 10 . The 10 weights assigned according to chronological order are: W1, W2, W3, W4, W5, W6, W7, W8, W9, W 10 ; The sum of the weights is 1. For example, the 10 weights are: 0.02, 0.03, 0.04, 0.05, 0.08, 0.09, 0.15, 0.2, 0.2, 0.15.

[0090] By designing S11~S14, correct the actual opening B of the gas valve collected, then obtain the corresponding ideal voltage detection value, and finally calculate the alarm threshold, an alarm threshold that changes with the change of the valve opening can be obtained, improving the accuracy of the obtained alarm threshold, and further improving the accuracy of subsequent fault judgment.

[0091] The fault detection method for gas stoves in this embodiment, after the gas valve of the gas stove is opened, collect the actual opening of the gas valve, calculate and update the alarm threshold according to the collected actual opening of the gas valve; collect the actual flame temperature of the burner head, and when the actual flame temperature is less than the alarm threshold, output a fault alarm. The fault detection method of this embodiment calculates the alarm threshold according to the actual opening of the valve and makes a fault alarm judgment according to the alarm threshold, which can not only ensure rapid detection of fault alarms, but also avoid misjudgment and improve the accuracy of fault detection and alarm.

[0092] The fault detection method for gas stoves in this embodiment calculates the alarm threshold according to the actual opening of the valve, and obtains an alarm threshold that changes with the change of the actual opening of the valve, avoiding the problems of false alarms or long alarm delays caused by using fixed alarm values.

[0093] The real-time output signal of the thermocouple can be directly collected. However, when a fault occurs (such as accidental flameout), the temperature of the thermocouple will change unexpectedly. At this time, the alarm has not been triggered yet. If the alarm threshold is calculated based on the actual temperature change of the thermocouple, the calculation result will be incorrect. Therefore, in this embodiment, the real-time output signal of the thermocouple is not directly used to calculate the alarm threshold. Instead, an ideal value is estimated according to the actual opening of the valve (equivalent to the detected value corresponding to the virtual thermocouple output signal), and different weights are assigned according to the chronological order, and then the calculation of the alarm threshold is completed to provide a relatively accurate alarm threshold, thereby improving the timeliness and accuracy of alarm judgment.

[0094] To prevent the problem that the temperature of the thermocouple is significantly too low at the minimum firepower, resulting in misjudgment of the fault or even inability to maintain the flame, air holes can be added in the direction of the burner head towards the thermocouple, so that there is still a part of the flame surrounding or completely surrounding the thermocouple probe at the minimum firepower, to further improve the accuracy of alarm judgment.

[0095] To further improve the accuracy of fault detection, in this embodiment, when it is continuously judged m times that the actual flame temperature of the burner head collected is less than the alarm threshold, a fault alarm is output; where m > 1. For example, m = 2, when it is continuously judged 2 times that the actual flame temperature of the burner head collected is less than the alarm threshold, a fault alarm is output.

[0096] The gas valve is a solenoid valve, which can be manually closed by turning the knob on the stove top panel or automatically closed by the controller driving the gas valve. However, due to stove failures, after the valve is manually or automatically operated to close, the valve may not close properly, still have a certain opening, and still have a flame. Therefore, in this embodiment, the fault detection method further includes the following steps:

[0097] After operating the gas valve of the gas stove to close, delay for a set time, collect the actual flame temperature of the burner head, and judge whether the actual flame temperature is greater than a preset fixed threshold; when the actual flame temperature is greater than the fixed threshold, it means that the thermocouple temperature is too high and the stove fails to turn off the fire. At this time, a fault alarm is output to prompt the user. The alarm methods include sound and light alarm, text message alarm, network alarm, etc. At the same time of the alarm, the gas source can also be directly cut off to avoid accidents.

[0098] To further improve the accuracy of fault detection, in this embodiment, after operating the gas valve of the gas stove to close, delay for a set time, collect the actual flame temperature of the burner head. When it is continuously judged M times that the actual flame temperature of the burner head collected is greater than the fixed threshold, a fault alarm is output; where M > 1. For example, M = 2, when it is continuously judged 2 times that the actual flame temperature of the burner head collected is greater than the fixed threshold, a fault alarm is output. M and m can be equal or not equal.

[0099] As another preferred design solution of this embodiment, when the cooking appliance fails to ignite successfully, there is no need to collect the actual opening degree of the valve at this time. To avoid unnecessary calculations, a fixed threshold is adopted. When the actual flame temperature of the burner head collected is less than the fixed threshold, a fault alarm is output.

[0100] Embodiment Two

[0101] Based on the design of the fault detection method in Embodiment One, this embodiment proposes a gas stove, which mainly includes a burner head, a valve opening degree acquisition device, a temperature detection device, a controller, etc., as shown in Figure 3 shown.

[0102] The valve opening degree acquisition device is used to collect the actual opening degree of the gas valve and send it to the controller. For example, the valve opening degree acquisition device collects the actual opening degree of the valve through a ring-shaped sliding rheostat coaxially linked with the valve.

[0103] The temperature detection device is installed on the burner head and is used to collect the actual flame temperature of the burner head and output a detection signal to the controller.

[0104] The controller is used to control the valve opening degree acquisition device to collect the actual opening degree of the gas valve after the gas valve of the gas stove is opened, calculate and update the alarm threshold according to the collected actual opening degree of the gas valve, and the alarm threshold directly or indirectly reflects the normal flame temperature at the actual opening degree of the gas valve; control the temperature detection device to collect the actual flame temperature of the burner head, and output a fault alarm when the actual flame temperature is less than the alarm threshold.

[0105] In this embodiment, the temperature detection device is preferably a thermocouple. The thermocouple collects the actual flame temperature of the burner head and outputs a voltage detection signal to the controller. The controller performs analog-to-digital conversion on the received voltage detection signal to generate a voltage sampling value. The voltage sampling value reflects the actual flame temperature; correspondingly, the alarm threshold is the voltage threshold corresponding to the normal flame temperature at the opening degree of the gas valve; when the voltage sampling value is less than the voltage threshold, a fault alarm is output.

[0106] As a preferred design solution of this embodiment, the controller includes a correction module, a detection value calculation module, a threshold calculation module, an AD conversion module, a judgment alarm module, etc., as shown in Figure 3 shown.

[0107] The correction module is used to receive the actual opening degree B of the gas valve collected by the valve opening degree acquisition device, correct the actual opening degree B of the gas valve, and obtain the corrected valve opening degree A i , and send it to the detection value calculation module.

[0108] A detection value calculation module, configured to obtain the valve opening degree A according to the preset corresponding relationship between the valve opening degree and the ideal voltage detection value i and send the corresponding ideal voltage detection value to the threshold calculation module.

[0109] A threshold calculation module, configured to calculate and update the alarm threshold according to the obtained ideal voltage detection value; send the alarm threshold to the alarm judgment module.

[0110] An AD conversion module, configured to receive the voltage detection signal output by the temperature detection device, perform analog-to-digital conversion on the received voltage detection signal to generate a voltage sampling value, and send it to the alarm judgment module.

[0111] An alarm judgment module, configured to output a fault alarm when the voltage sampling value is less than the alarm threshold.

[0112] In the gas stove of this embodiment, after the gas valve of the gas stove is opened, the valve opening degree acquisition device is controlled to acquire the actual opening degree of the gas valve, and the alarm threshold is calculated and updated according to the acquired actual opening degree of the gas valve; the temperature detection device is controlled to acquire the actual flame temperature of the burner head, and a fault alarm is output when the actual flame temperature is less than the alarm threshold. In the gas stove of this embodiment, the alarm threshold is calculated according to the actual valve opening degree, and the fault alarm judgment is made according to the alarm threshold, which can not only ensure the rapid detection of the fault alarm, but also avoid misjudgment, and improve the accuracy of the fault detection and alarm.

[0113] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fault detection method for a gas stove, characterized in that, Including: Operate the gas valve of the gas stove to open. Collect the actual opening degree of the gas valve, and calculate and update the alarm threshold according to the collected actual opening degree of the gas valve. Collect the actual flame temperature of the burner head, and output a fault alarm when the actual flame temperature is less than the alarm threshold. Set a first sampling period. Within each first sampling period, collect the actual opening degree of the gas valve, and calculate and update the alarm threshold according to the continuously collected n actual opening degrees of the gas valve. Set a second sampling period. Within each second sampling period, collect the actual flame temperature of the burner head, compare it with the alarm threshold, and output a fault alarm when the actual flame temperature is less than the alarm threshold. The first sampling period is greater than the second sampling period.

2. The fault detection method according to claim 1, wherein, Collect the actual flame temperature of the burner head through a temperature detection device, and output a voltage detection signal. Generate a voltage sampling value according to the voltage detection signal, and the voltage sampling value reflects the actual flame temperature of the burner head. The alarm threshold is the voltage threshold corresponding to the normal flame temperature at the actual opening degree of the gas valve. The process of collecting the actual opening degree of the gas valve and calculating and updating the alarm threshold according to the collected actual opening degree of the gas valve includes: Collect the actual opening degree B of the gas valve. Obtain the ideal voltage detection value according to the preset corresponding relationship between the valve opening degree and the ideal voltage detection value. Calculate and update the alarm threshold according to the obtained ideal voltage detection value.

3. The fault detection method according to claim 2, wherein After collecting the actual gas valve opening B, first correct the actual gas valve opening B to obtain the corrected valve opening A i ; Then, the valve opening A is obtained according to the corresponding relationship between the preset valve opening and the ideal voltage detection value i The corresponding ideal voltage detection value; The correction formula is: where B ∈ [0, 1]; when B = 1, it means the valve is fully open and the valve is at the maximum fire position; when B = 0.2, the valve is at the minimum fire position; when B = 0, it means the valve is fully closed.

4. The fault detection method according to claim 3, wherein The corresponding relationship between the valve opening degree and the ideal voltage detection value is: Among them, U i is the ideal voltage detection value, U max is the ideal voltage detection value when the valve is in the maximum fire power position, and U min is the ideal voltage detection value when the valve is in the minimum fire power position.

5. The fault detection method according to claim 4, wherein The formula for calculating and updating the alarm threshold according to the obtained ideal voltage detection value is: Among them, U alm is the alarm threshold, K is a constant, 0.7 ≤ K ≤ 0.9; W i is the weight of U i ; the sum of the weights is 1.

6. The fault detection method according to claim 1, characterized in that When it is continuously judged m times that the actual flame temperature of the collected burner head is less than the alarm threshold, output a fault alarm; where m > 1.

7. The fault detection method according to any one of claims 1 to 6, characterized in that The fault detection method further includes: After operating the gas valve to close, delay for a set time, collect the actual flame temperature of the burner head, and output a fault alarm when the actual flame temperature is greater than the preset fixed threshold.

8. The fault detection method according to claim 7, wherein, When it is continuously judged M times that the actual flame temperature of the collected burner head is greater than the fixed threshold, output a fault alarm; where M > 1.

9. A gas stove, characterized in that, Including: A valve opening degree collection device for collecting the actual opening degree of the gas valve. A temperature detection device for collecting the actual flame temperature of the burner head. A controller for controlling the valve opening degree collection device to collect the actual opening degree of the gas valve after operating the gas valve of the gas stove to open, calculating and updating the alarm threshold according to the collected actual opening degree of the gas valve; controlling the temperature detection device to collect the actual flame temperature of the burner head, and outputting a fault alarm when the actual flame temperature is less than the alarm threshold. It is also used to set a first sampling period. Within each first sampling period, the actual opening degree of the gas valve is collected, and based on the continuously collected n actual opening degrees of the gas valve, the alarm threshold is calculated and updated; A second sampling period is set. Within each second sampling period, the actual flame temperature of the burner is collected and compared with the alarm threshold. When the actual flame temperature is lower than the alarm threshold, a fault alarm is output; The first sampling period is greater than the second sampling period.

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