A method for determining and controlling the working condition of abnormal combustion of a cooking appliance, and a cooking appliance

Abstract

The application discloses a kind of stove abnormal combustion's sub-condition determination control method, stove, the method includes the following steps: by abnormal combustion protection switch receiving on-off instruction, shield protection logic when closing, then execute subsequent steps when starting;Real-time acquisition burner temperature data using thermistor located between outer ring fire cover and center fire cover on burner burner head cover plate;According to temperature threshold value determination single burner or multiple burner working condition, when switching mode, synchronous switching abnormal determination standard;According to corresponding working condition, adopt different temperature rise slope interval and limit temperature threshold, temperature is greater than or equal to 100 DEG C, start slope determination, any condition satisfies, it is determined that abnormal combustion;Determine abnormality, output instruction cuts off stove main gas passage.The application can accurately identify abnormal combustion of stove under different working conditions, and consider safety protection and use demand, quickly cut off gas to reduce safety risk.

Description

Technical Field

[0001] This invention relates to the field of household gas stove technology, and in particular to a method for determining and controlling abnormal combustion conditions in a stove, and a stove in general. Background Technology

[0002] Gas stoves, widely used cooking appliances in homes and commercial settings, are prone to abnormal combustion conditions such as dry burning, backfire, and flame leakage, which can easily lead to safety accidents. Therefore, abnormal combustion protection technology has become the core of gas stove safety design. However, existing abnormal combustion protection technologies for gas stoves still have many unresolved defects, resulting in poor protection effectiveness and limited user experience. The specific shortcomings of existing patented technologies are as follows: Lack of independent on / off control mechanism for protective functions: In existing technologies, the abnormal combustion protection logic of gas stoves is mostly in a forced-on state, and users cannot choose to turn it on or off according to the cooking scenario. For example, the protection solutions disclosed in patents CN202511939027, CN202010254567, and CN201810087296 do not have an independent on / off switch for the protection function, and the protection logic is always in a continuous running or forced-on state. This means that in special cooking scenarios such as prolonged high-temperature stir-frying or dry-frying, the protection logic is easily triggered and cuts off the gas, interfering with normal cooking; while some stoves without protection functions have no safety guarantee at all and cannot meet users' dual needs for safety and flexibility of use.

[0003] The design of the temperature measurement location is unreasonable, and the accuracy and coverage of temperature acquisition are insufficient: The existing temperature measurement element arrangement has obvious defects: Patent CN202010254567 uses an infrared temperature probe installed at the range hood to achieve protection by collecting the temperature of the stove plate or pot, but it is far from the core combustion area and cannot quickly capture temperature changes in conditions such as backfire and flame leakage, and is easily affected by ambient airflow and flame deviation; Although patent CN201810087296 optimizes the hardware structure of the non-contact sensor (adding a heat insulation cover), it still takes the bottom of the pot as the main detection object, and does not change the fundamental problem that the temperature measurement position is far from the core combustion area; Patent CN202511939027 uses dual-point temperature measurement of the bottom of the pot and the stove body, but the core detection object is still the temperature of the pot body, which can only respond to dry burning conditions, and the contact temperature measurement is easily affected by the displacement, deformation of the pot, and foreign objects attached to the bottom of the pot, resulting in temperature measurement distortion. In addition, these solutions all require additional drilling or modification of the stove structure, resulting in poor compatibility, high modification costs, and the inability to achieve concealed installation using the original stove structure.

[0004] The lack of consideration for differences in combustion conditions and the use of a single judgment standard lead to compatibility defects: when a gas stove operates with a single burner versus multiple burners simultaneously, there are significant differences in the burner's heat output power and the distribution of the internal heat field—when a single burner operates, the heat radiation is low and the temperature rises slowly, while when multiple burners operate, the heat radiation is superimposed and the base temperature rises. Existing patented technologies do not provide a normalized distinction for these conditions: Patent CN202010254567 only uses a single logic of "fixed temperature threshold + duration" to determine whether it is dry-burning or empty-burning; Patent CN201810087296 only focuses on sensor hardware optimization and lacks a software judgment logic for condition adaptation design; although Patent CN202511939027 temporarily judges whether the flame is adjusted after determining dry-burning and adjusts the judgment conditions accordingly, it does not establish a normalized condition identification and adaptation system, and is essentially still a localized optimization of a single judgment standard. The above design results in the protection being easily triggered by slight temperature fluctuations under low load conditions (single burner operation), and under high load conditions (multiple burners operation), abnormal combustion is missed due to insufficient temperature threshold adaptation, resulting in low protection accuracy.

[0005] The logic for determining abnormal combustion is simplistic, leading to blind spots and the risk of false triggering. Existing technologies lack comprehensiveness: Patent CN202010254567 uses only a fixed temperature threshold as the core criterion, failing to identify slow-rising dry-burning conditions and resulting in delayed protection response; Patent CN202511939027 introduces temperature rise rate determination but does not limit its activation temperature range, making it prone to false triggering due to ambient temperature fluctuations or instantaneous temperature rises at low temperatures; Patent CN201810087296 does not involve software logic innovation, relying solely on sensor hardware to improve temperature measurement accuracy, failing to address the inherent defects of a single-logic approach. Furthermore, existing solutions lack a dual protection logic of "dynamic temperature rise recognition + extreme temperature fallback," resulting in either blind spots or high false triggering rates, making it difficult to comprehensively and accurately identify various abnormal combustion conditions such as dry burning, backfire, and flame leakage.

[0006] In summary, existing abnormal combustion protection technologies for gas stoves have significant shortcomings in terms of functional flexibility, temperature measurement accuracy, adaptability to operating conditions, and judgment precision. They cannot effectively balance safety protection and user experience, and there is an urgent need for a technical solution that can solve the above problems. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to provide a method for determining and controlling abnormal combustion in a stove under different operating conditions, and a stove that can accurately identify abnormal combustion under different operating conditions, taking into account both safety protection and usage needs, and quickly cutting off the gas supply to reduce safety risks.

[0008] To address the aforementioned technical problems, the first aspect of this invention discloses a method for determining and controlling abnormal combustion conditions in a stove, comprising the following steps: (1) Function opening and closing judgment steps: The user's opening and closing instructions are received in real time through the abnormal combustion protection function opening and closing switch configured on the stove; when the closing instruction is received, all abnormal combustion protection control logic is blocked; when the opening instruction is received, the following steps (2) to (5) are executed. (2) Temperature acquisition steps: The temperature data of the corresponding burner area is collected in real time by the thermistor temperature sensor arranged on the burner head cover plate of each burner of the stove and located in the area between the outer ring fire cover and the center fire cover of the burner; the burner head cover plate is the upper sealing cover plate of the burner mixing chamber. (3) Real-time operating condition identification steps: operating condition is determined based on the collected temperature data; when the temperature of only a single burner is ≥ the preset effective combustion temperature threshold, it is determined to be a single burner operating condition; when the temperature of at least two burners is ≥ the effective combustion temperature threshold, it is determined to be a multi-burner operating condition; when the operating condition is switched, the judgment criteria for abnormal combustion are switched synchronously and automatically. (4) Abnormal combustion judgment steps: Based on the currently identified operating conditions, the corresponding differentiated judgment criteria are used to judge the abnormality. If any judgment condition is met, it is judged as an abnormal combustion state. Among them, the single burner operating condition is set with a first temperature rise slope judgment range and a first limit temperature threshold, and the multi-burner operating condition is set with a second temperature rise slope judgment range and a second limit temperature threshold. The temperature rise slope judgment is only activated when the collected temperature is ≥100℃. (5) Safety protection execution steps: When it is determined that the combustion state is abnormal, the control command is output to cut off the main gas passage of the stove.

[0009] As an optional implementation, in the first aspect of the present invention, in step (2), the burner cover is a flat metal mounting surface that is built into the burner and does not require additional openings. It is sealed and fitted with the combustion chamber of the burner to provide an installation reference for the outer ring burner cover, the center burner cover and the temperature sensor.

[0010] As another optional implementation, in the first aspect of the present invention, in step (2), the thermistor temperature sensor is an NTC thermistor, whose temperature sensing surface is attached to the surface of the corresponding burner cover plate and is fixed by a high-temperature resistant fixing structure to collect the radiation temperature of the corresponding burner area in a non-contact manner.

[0011] As another optional implementation, in the first aspect of the present invention, in step (3), the effective combustion temperature threshold is the lowest critical temperature that distinguishes the burner standby state from the effective combustion state; and in step (4), the temperature rise slope is the ratio of the temperature change per unit time to time, i.e., temperature rise slope = ΔT / Δt, where ΔT is the temperature change per unit time in K, and Δt is the preset unit time.

[0012] As another optional implementation, in the first aspect of the present invention, the preset unit time is 15 seconds; the reference value of the effective combustion temperature threshold is 50°C.

[0013] As another optional implementation, in the first aspect of the invention, in step (4): The first temperature rise slope determination range is: the detected temperature is in the range of 100℃~210℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~5K / 15s; the first extreme temperature threshold is 210℃. The second temperature rise slope determination range is: the detection temperature is in the range of 100℃~220℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~6K / 15s; the second extreme temperature threshold is 220℃.

[0014] The second aspect of this invention discloses a stove, including a burner assembly, a temperature measuring module, a control module, a gas on / off execution unit, an abnormal combustion protection function on / off switch, and a power supply module; The burner assembly includes at least one independent burner, and each burner is provided with at least one NTC thermistor. The NTC thermistors constitute the temperature measurement module. The thermistor temperature sensor is arranged on the burner head cover plate of the corresponding burner and is located in the area between the outer ring fire cover and the center fire cover of the burner. The burner head cover plate is the upper sealing cover plate of the burner head mixing chamber. The abnormal combustion protection function on / off switch is fixed to the operating area of ​​the stove panel, and its signal output terminal is electrically connected to the IO pin of the control module. The gas on / off control unit is connected in series in the main gas passage of the stove, and its control terminal is electrically connected to the drive output terminal of the control module. The sampling input terminal of the control module is electrically connected to the signal output terminal of the temperature measurement module. The control module has a built-in differentiated anomaly determination logic unit corresponding to the single burner working condition and the multi-burner working condition respectively. The differentiated anomaly determination logic unit executes the control method according to any one of claims 1-6. The output terminal of the power module is electrically connected to the power supply terminals of the temperature measurement module, the control module, the gas on / off execution unit, and the abnormal combustion protection function on / off switch, respectively.

[0015] As an optional implementation, in the second aspect of the present invention, the burner cover is a flat metal mounting surface integrated with the burner, which is sealed and fitted with the combustion chamber of the burner, and a fixing mounting lug for fixing the burner cover to the stove body is integrally provided on its side; the thermistor temperature sensor is an NTC thermistor, whose temperature sensing surface is closely attached to the surface of the burner cover and is fixed by a high-temperature resistant fixing structure.

[0016] As another optional implementation, in the second aspect of the present invention, the temperature measurement range of the NTC thermistor is -40℃ to 300℃, the response time is ≤0.5s, and the temperature measurement accuracy is ±1%; and the gas on / off actuator is a normally closed gas solenoid valve with an on / off response time ≤0.3s.

[0017] As another optional implementation, in the second aspect of the present invention, the abnormal combustion protection function on / off switch is a waterproof and oil-proof switch, which is connected in series with an LED status indicator light, which is used to visually display the on / off status of the abnormal combustion protection function on / off switch; the control module adopts a microcontroller, which has a built-in AD sampling unit and a built-in multi-channel independent sampling channel matching the number of burners, and each NTC thermistor is connected to an independent sampling channel.

[0018] The third aspect of the present invention discloses a control device for determining the working condition of an abnormal combustion stove, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps in the method disclosed in the first aspect of the present invention.

[0019] The fourth aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method disclosed in the first aspect of the present invention.

[0020] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: Compared to existing technologies, this invention's embodiments utilize a pre-set function activation / deactivation logic to balance stove safety with personalized user needs. Users can independently activate or deactivate the protection logic based on cooking scenarios, avoiding conflicts between the protection logic and specific cooking conditions and enhancing the user experience. The temperature measurement layout between the outer ring burner and the central burner allows for simultaneous monitoring of the combustion status of both the inner and outer rings. Compared to traditional temperature measurement locations such as the outside of the burner or the bottom of the pot, this approach can more quickly and accurately capture temperature changes in abnormal conditions such as dry burning, backfire, and flame leakage. Furthermore, a real-time dynamic identification mechanism for single / multiple burner operating conditions is established, automatically switching differentiated anomaly judgment standards based on the actual combustion status of the stove, adapting to the internal heat field distribution and heat distribution under different operating conditions. The output characteristics address industry pain points such as false triggering under low load conditions and delayed identification under high load conditions caused by a single judgment standard. It adopts a dual anomaly judgment logic of "dynamic recognition of temperature rise slope + fallback of extreme temperature threshold". It clearly defines the 100℃ start threshold for temperature rise slope judgment. It can identify abnormal combustion temperature change characteristics in advance by using temperature rise slope to achieve pre-emptive protection against abnormal conditions, and it can also provide fallback protection by using extreme temperature threshold to eliminate the protection blind spot of single judgment logic. At the same time, it avoids false triggering in the low temperature stage, which greatly improves the accuracy and reliability of protection. When an abnormal combustion state is judged, the main gas circuit of the stove is directly cut off. The action is direct and the response is reliable. It can quickly terminate abnormal combustion and reduce the risk of stove safety accidents. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a flowchart illustrating a method for determining and controlling abnormal combustion in a stove according to an embodiment of the present invention. Figure 2 This is another flowchart illustrating a method for determining and controlling abnormal combustion in a stove, as disclosed in an embodiment of the present invention. Figure 3 This is a partial structural schematic diagram of a stove disclosed in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a stove abnormal combustion condition judgment and control device disclosed in an embodiment of the present invention. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1 See Figures 1-2 This invention discloses a method for determining and controlling abnormal combustion conditions in a stove, comprising the following steps: (1) Function activation / deactivation judgment steps: The abnormal combustion protection function of the stove is turned on and off in real time by receiving the user's turn-on and turn-off instructions; when the turn-off instruction is received, all abnormal combustion protection control logic is blocked; when the turn-on instruction is received, the following steps (2) to (5) are executed.

[0025] (2) Temperature acquisition steps: Temperature data for the corresponding burner area is collected in real time by a thermistor temperature sensor located on the burner head cover plate of each burner in the stove, in the area between the outer ring burner cap and the center burner cap. The burner head cover plate is the upper sealing cover plate of the burner head mixing chamber.

[0026] (3) Real-time operating condition identification steps: Operating conditions are determined based on the collected temperature data: when the temperature corresponding to only a single burner is ≥ the preset effective combustion temperature threshold, it is determined to be a single burner operating condition; when the temperature corresponding to at least two burners is ≥ the effective combustion temperature threshold, it is determined to be a multi-burner operating condition. The criteria for determining abnormal combustion are automatically switched synchronously during operating condition switching.

[0027] (4) Steps for determining abnormal combustion: Based on the currently identified operating conditions, corresponding differentiated judgment criteria are used to determine anomalies. If any judgment condition is met, it is determined to be an abnormal combustion state. Specifically, the single burner operating condition is set with a first temperature rise slope judgment range and a first limit temperature threshold, while the multi-burner operating condition is set with a second temperature rise slope judgment range and a second limit temperature threshold. The temperature rise slope judgment is only activated when the collected temperature is ≥100℃.

[0028] (5) Safety protection implementation steps: When an abnormal combustion state is detected, a control command is output to cut off the main gas supply to the stove.

[0029] The "real-time acquisition" and "real-time identification" mentioned in this method refer to the control module cyclically performing temperature acquisition and operating condition determination at a fixed sampling frequency. This is a dynamic cyclical execution process. When the operating condition changes, the abnormal combustion determination standard switches synchronously without delay, and there is no blind spot in the determination time. The "shielding all abnormal combustion protection control logic" in this method means that after the shutdown command takes effect, the control module no longer performs operating condition identification, abnormal combustion determination, and safety protection actions. It only retains the functions of temperature acquisition and on / off status detection. The stove can still perform basic operations such as ignition and firepower adjustment normally. This method is applicable to all types of household / commercial gas stoves, including single-burner stoves, double-burner stoves, and multi-burner stoves. For single-burner stoves, the determination standard for single burner operating condition is only applicable. For three-burner and above multi-burner stoves, the single burner operating condition corresponds to the scenario where only one burner is burning, and the multi-burner operating condition corresponds to the scenario where two or more burners are burning simultaneously. The operating condition determination is exclusive. At any given time, it can only be determined as either single burner operating condition or multi-burner operating condition. There is no scenario where both operating conditions are effective at the same time.

[0030] The temperature measuring point is selected in the burner head cover area between the outer ring burner cap and the central burner cap. This location is the core temperature-sensitive area of ​​the stove's combustion zone: during dry burning, radiant heat from the bottom of the pot quickly accumulates here; during backfire, the flame burns in the opposite direction from the mixing chamber and directly acts on this area; during flame leakage, the flame leaks from the gap between the burner caps and first contacts this area. It has the characteristics of high temperature response sensitivity and can truly reflect the combustion state. At the same time, this location is the original structure of the stove burner head. The NTC thermistor is fixed by the flat metal surface of the burner head cover, without the need for additional drilling and modification, achieving concealed installation and direct compatibility with existing stove production lines.

[0031] This invention employs a pre-configured function activation / deactivation logic that balances cooktop safety with personalized user needs. Users can independently activate or deactivate the protection logic based on their cooking scenario, avoiding conflicts between the protection logic and specific cooking conditions and enhancing the user experience. The temperature measurement layout between the outer and central burner caps allows for simultaneous monitoring of the combustion status of both the inner and outer rings. Compared to traditional temperature measurement locations such as the outside of the burner or the bottom of the pot, this approach can more quickly and accurately detect temperature changes in abnormal conditions such as dry burning, backfire, and flame leakage. Furthermore, a real-time dynamic identification mechanism for single / multi-burner operating conditions is established, automatically switching differentiated anomaly judgment standards based on the actual combustion status of the cooktop, adapting to the internal heat field distribution and heat output characteristics of the cooktop under different operating conditions. This system addresses industry pain points such as false triggering under low load conditions and delayed identification under high load conditions caused by a single judgment standard. It adopts a dual anomaly judgment logic of "dynamic recognition of temperature rise slope + fallback of extreme temperature threshold". It clearly defines the 100℃ start threshold for temperature rise slope judgment. It can identify abnormal combustion temperature change characteristics in advance through temperature rise slope to achieve pre-emptive protection against abnormal conditions, and it can also provide fallback protection through extreme temperature threshold to eliminate the protection blind spot of single judgment logic. At the same time, it avoids false triggering in the low temperature stage, which greatly improves the accuracy and reliability of protection. When an abnormal combustion state is judged, the main gas circuit of the stove is directly cut off. The action is direct and the response is reliable. It can quickly terminate abnormal combustion and reduce the risk of stove safety accidents.

[0032] In an optional embodiment, in step (2), the burner cover is a flat metal mounting surface that comes with the burner and does not require additional openings. It is sealed and fitted with the combustion chamber of the burner, providing an installation reference for the outer ring burner cover, the center burner cover and the temperature sensor.

[0033] The phrase "no additional drilling required" means that the temperature sensor is directly installed on the existing flat area of ​​the burner head cover, without the need for additional installation holes on the burner head cover, thus preserving the sealing performance of the burner head mixing chamber. The burner head cover and the burner head mixing chamber are sealed together to prevent gas leakage within the mixing chamber and ensure the combustion stability and safety of the burner.

[0034] This embodiment clarifies that the burner cover is an existing structure integrated into the burner, requiring no additional drilling or modification of the burner body. It can be directly adapted to existing mainstream stove production lines, resulting in low modification costs and easy mass production and promotion. The embodiment also clarifies the sealing and installation reference functions of the burner cover, ensuring consistency in the installation positions of the outer ring burner cap, center burner cap, and temperature sensor, thus improving the stability of temperature measurement accuracy and protection during mass production. Using a flat metal mounting surface as the installation reference ensures a tight fit between the temperature sensor and the mounting surface, improving heat transfer efficiency and guaranteeing accurate temperature measurement and response speed.

[0035] In another optional embodiment, in step (2), the thermistor temperature sensor is an NTC thermistor, whose sensing surface is attached to the surface of the corresponding burner cover plate and fixed by a high-temperature resistant fixing structure, so as to collect the radiation temperature of the corresponding burner area in a non-contact manner.

[0036] The non-contact acquisition refers to the thermistor not directly contacting the combustion flame or the heated cookware, but monitoring the combustion status by collecting the heat radiation from the burner area and the heat conduction temperature of the burner cover. The high-temperature resistant fixing structure is a fixing method adapted to the high-temperature working environment of the stove, including but not limited to high-temperature resistant ceramic adhesive bonding, high-temperature resistant buckle fixing, and other fixing methods that do not damage the structure of the burner cover.

[0037] Non-contact temperature measurement eliminates the reliance on physical contact with the bottom of the pot in traditional contact temperature measurement. The NTC thermistor reflects the combustion state by collecting the ambient radiation temperature of the combustion zone and the conduction temperature of the burner cover. Scenarios such as the range hood blowing the flame off course, the pot shifting / deforming, or oil and foreign matter adhering to the bottom of the pot will not affect the effectiveness of temperature collection, thus eliminating the misjudgment defects of contact temperature measurement from the root.

[0038] This embodiment explicitly uses an NTC thermistor as the temperature sensing element, which has a wide temperature measurement range, fast response speed, and low cost, making it suitable for the usage scenarios and mass production needs of household stoves. The clearly defined installation method of attaching and fixing the sensing surface ensures full contact between the thermistor and the burner cover, reducing temperature measurement errors and improving the accuracy of temperature acquisition. The use of a non-contact radiation temperature measurement method prevents the thermistor from directly contacting the flame, avoiding issues such as shortened component lifespan and accuracy degradation caused by high-temperature burning, thus improving the long-term reliability of the product. The high-temperature resistant fixing structure ensures secure installation under long-term high-temperature conditions, adapting to the high-temperature working environment of the stove's combustion zone and preventing protective failure due to component detachment.

[0039] In another optional embodiment, in step (3), the effective combustion temperature threshold is the lowest critical temperature that distinguishes the burner standby state from the effective combustion state.

[0040] The baseline calibration value of the effective combustion temperature threshold is 50℃. This value is the minimum critical temperature for stable combustion after the burner of a household stove is ignited. It can effectively distinguish between ambient temperature and burner operating temperature, and avoid misjudgment of operating conditions caused by ambient temperature interference. This threshold can be fine-tuned according to the rated heat load of the stove, the burner material, and the ambient temperature. The fine-tuning range is 45℃~55℃.

[0041] This embodiment clarifies the core judgment criteria for operating condition identification, which can accurately distinguish between the burner's unignited standby state and the effective combustion state after ignition, avoiding misidentification of operating conditions caused by ambient temperature interference in the standby state, and ensuring the accuracy of operating condition judgment; this threshold can be flexibly adapted to different stoves' combustion power and burner structure, and has good product versatility.

[0042] In another optional embodiment, in step (4), the temperature rise slope is the ratio of the temperature change per unit time to time, i.e., temperature rise slope = ΔT / Δt, where ΔT is the temperature change per unit time in Kelvin (K), and Δt is the preset unit time. Optionally, the preset unit time can be 15 seconds; the baseline value of the effective combustion temperature threshold can be 50°C.

[0043] Optionally, the unit of temperature change ΔT in the formula is Kelvin (K). The temperature change of 1K is equal to 1℃. The temperature difference in degrees Celsius can be used directly for calculation without conversion obstacles. The temperature rise slope is continuously calculated using a sliding window method. That is, every time a new temperature data is collected, the temperature rise slope value in the most recent 15 seconds is updated to ensure real-time identification of abnormal temperature rise.

[0044] This embodiment clarifies the standardized calculation method for the temperature rise slope, unifies the statistical time window for temperature change, eliminates the ambiguity in the calculation of the temperature rise slope, and ensures the consistency and repeatability of temperature rise judgment under different operating conditions. The 15-second time window not only ensures the stability of temperature data acquisition and avoids the distortion of slope calculation caused by instantaneous temperature fluctuations, but also allows for rapid response to abnormal temperature rises, taking into account both the anti-interference capability and response speed of the judgment.

[0045] In yet another optional embodiment, in step (4): The first temperature rise slope determination range is: the detected temperature is in the range of 100℃~210℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~5K / 15s; the first extreme temperature threshold is 210℃. The second temperature rise slope determination range is: the detection temperature is in the range of 100℃~220℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~6K / 15s; the second extreme temperature threshold is 220℃.

[0046] The temperature range, temperature rise slope range, and extreme temperature threshold mentioned are all measured calibration values ​​of household stoves with rated heat loads of 3.8kW to 5.2kW. These values ​​can be fine-tuned according to the stove's combustion power, burner structure, and material characteristics. In this embodiment, the two judgment conditions are logically related as "OR," namely, the temperature rise slope judgment condition and the extreme temperature threshold judgment condition. If either condition is met, it is determined to be an abnormal combustion state; both conditions do not need to be met simultaneously. When the collected temperature exceeds the extreme temperature threshold of the corresponding operating condition, regardless of whether the temperature rise slope falls into the abnormal range, it is directly determined to be an abnormal combustion state, and safety protection actions are executed to achieve fallback protection.

[0047] There are fundamental differences in the heat output power of the burner and the heat field distribution inside the stove when a single burner is burning and when multiple burners are burning simultaneously: when a single burner is working, the heat radiation is small, the temperature rise in the burner area is relatively slow, and the upper limit of the normal cooking temperature is low; when multiple burners are working simultaneously, the heat radiation from both burners is superimposed, the overall base temperature of the stove's internal cavity rises, and the upper limit of the normal cooking temperature is correspondingly increased. This invention, based on an effective combustion temperature threshold of 50℃, distinguishes between single-burner and multi-burner operating conditions of stoves and sets differentiated anomaly judgment criteria for different operating conditions: for single-burner operating conditions, a limit temperature threshold of 210℃ and an abnormal temperature rise slope range of 1K / 15s~5K / 15s are set to adapt to its low-load thermal field characteristics; for multi-burner operating conditions, a limit temperature threshold of 220℃ and an abnormal temperature rise slope range of 1K / 15s~6K / 15s are set to adapt to its high-load thermal field characteristics, achieving accurate matching between protection standards and actual combustion conditions, and solving the industry pain point of "easy false triggering under low load and easy missed detection under high load" of a single judgment criterion.

[0048] During normal cooking, when the temperature rises above 100℃, the heat absorption of the cookware, heat radiation, and heat dissipation from the environment reach a dynamic equilibrium, and the temperature in the burner area rises slowly with a stable temperature rise slope within a small range. However, in abnormal combustion states such as dry burning, backfire, and leaking flames, without continuous heat absorption from food, heat accumulates rapidly, and the temperature rise slope changes abruptly, falling into a pre-defined abnormal range. By dynamically determining the temperature rise slope, the temperature change patterns of abnormal combustion can be accurately identified, triggering protection before the temperature reaches the danger threshold, thus solving the problem of delayed protection in traditional fixed temperature threshold determination. At the same time, an extreme temperature threshold is set as a fallback judgment. 210℃ and 220℃ are the highest safe temperatures that a household stove can reach during normal cooking (including stir-frying) under single-burner and multi-burner conditions, respectively. Once the temperature reaches this threshold, regardless of whether the temperature rise slope falls into the abnormal range, it is directly judged as abnormal combustion, avoiding missed detection due to slope calculation errors or extreme conditions, thus constructing a dual safety system of "dynamic early identification + static fallback protection".

[0049] This embodiment clarifies the differentiated judgment parameters under single / multi-burner operating conditions, accurately adapting to the thermal field characteristics of single burner under low load and multi-burner under high load. This ensures that false protection is not triggered in normal cooking scenarios, while accurately identifying abnormal combustion states such as dry burning, backfire, and flame leakage. The clearly defined numerical ranges and thresholds provide a direct execution benchmark for control program writing, facilitating direct implementation by those skilled in the art, while ensuring the consistency of protection performance of batch products. These parameters are actual measured calibration values ​​for mainstream household stoves, adapting to all cooking scenarios of household stoves, including stir-frying, stewing, and deep-frying, balancing protection safety and stove performance.

[0050] Example of actual working conditions: 1. Single-sided stir-fry (normal working condition): Turn on the left burner of the stove. In single-sided working condition, the temperature rises to 190℃. The temperature rises by 1.8K within 15 seconds. The temperature rise slope is 0.12K / 15s. It does not fall into the abnormal range. The protection function does not start. The stove works normally. 2. Single-sided dry burning (abnormal working condition): In single-sided working condition, after the food in the pot is burned dry, the temperature rises to 160℃, and the temperature rises by 4.2K within 15 seconds. The temperature rise slope is 2.8K / 15s, which falls into the abnormal range. The control module immediately outputs a command, and the gas solenoid valve closes the valve within 0.2s to cut off the gas supply and extinguish the flame. 3. Dual-sided stewing (normal operating condition): With both burners on, the temperature rises to 210℃ in dual-sided operation. The temperature rises by 0.9K within 15 seconds, and the temperature rise slope is 0.06K / 15s. It does not fall into the abnormal range, and the protection function is not activated. 4. Double-sided backfire (abnormal operating condition): In the double-sided operating condition, backfire occurs at the burner head, the temperature rises to 200℃, the temperature rises by 5.8K within 15 seconds, the temperature rise slope = 3.87K / 15s, falling into the abnormal range, the gas solenoid valve quickly closes the valve to achieve safety protection; 5. Extreme temperature protection (abnormal operating conditions): In unilateral operating conditions, if the temperature rises rapidly to 210℃ due to dry burning, regardless of the temperature rise slope, the control module will directly output a valve shut-off command to achieve protection. 6. Function switch off (temporary working condition): When the user manually turns off the firewall function switch, the indicator light goes out, the protection logic is blocked, and the stove can complete various temporary abnormal cooking operations. Turning the switch back on restores the protection function.

[0051] Example 2 See Figure 3 This invention discloses a stove, including a burner assembly, a temperature measuring module, a control module, a gas on / off execution unit, an abnormal combustion protection function on / off switch, and a power module; The burner assembly includes at least one independent burner, and each burner is equipped with at least one NTC thermistor 1. The NTC thermistors 1 constitute the temperature measurement module. The thermistor temperature sensor is arranged on the burner head cover plate 3 of the corresponding burner and is located in the area between the outer ring flame cap (not shown in the figure) and the center flame cap (not shown in the figure) of the burner. The burner head cover plate 3 is the upper sealing cover plate of the mixing chamber of the burner head 2. The abnormal combustion protection function on / off switch is fixed to the operating area of ​​the stove panel, and its signal output terminal is electrically connected to the IO pin of the control module. The gas on / off control unit is connected in series in the main gas passage of the stove, and its control terminal is electrically connected to the drive output terminal of the control module. The sampling input terminal of the control module is electrically connected to the signal output terminal of the temperature measurement module. The control module has built-in differentiated anomaly determination logic units corresponding to single burner working conditions and multi-burner working conditions, respectively. The differentiated anomaly determination logic units execute the control method described in Embodiment 1. The output terminal of the power module is electrically connected to the power supply terminals of the temperature measurement module, the control module, the gas on / off execution unit, and the abnormal combustion protection function on / off switch, respectively.

[0052] Appendix Figure 3 In the diagram, 5 is the outer ring flame mixing outlet, and 6 is the center flame mixing outlet. Conventionally, the center flame mixing outlet 6 is directly connected to the center flame cap, and the outer ring flame mixing outlet 5 is directly connected to the outer ring flame cap. The outer ring flame cap is the annular flame cap, and the center flame cap is located inside the ring of the outer ring flame cap; both are existing designs.

[0053] Optionally, when the control module determines that the combustion state is abnormal through its built-in logic, it immediately outputs a high-level drive signal to the gas on / off execution unit to forcibly cut off the main gas passage of the stove, terminate the abnormal combustion, and complete the safety protection action.

[0054] In an optional embodiment, the burner cover 3 is a flat metal mounting surface integrated with the burner 2, which is sealed to the gas mixing chamber of the burner 2, and a fixed mounting lug 4 is integrally provided on its side for fixing the burner cover 3 to the stove body; the thermistor temperature sensor is an NTC thermistor 1, whose temperature sensing surface is closely attached to the surface of the burner cover 3 and is fixed by a high-temperature resistant fixing structure.

[0055] Optionally, the high-temperature resistant fixing structure includes, but is not limited to, high-temperature resistant ceramic adhesive bonding, high-temperature resistant buckle fixing, and other fixing methods that do not damage the original structure of the burner cover plate 3. Its long-term temperature resistance is not lower than 300℃, which is suitable for the high-temperature working environment of the stove combustion area.

[0056] Optionally, by inserting fixing screws into the through holes of the support lugs 4, the entire burner cover 3 can be locked and fixed on the mounting surface of the stove bottom shell, ensuring that the installation position of the burner cover 3 does not shift or shake.

[0057] In another optional embodiment, the NTC thermistor 1 has a temperature measurement range of -40℃ to 300℃, a response time of ≤0.5s, and a temperature measurement accuracy of ±1%.

[0058] The parameters of the NTC thermistor 1 are the preferred calibration values ​​for the temperature measurement scenario of household stove burners, and can be finely adjusted within a reasonable range according to the rated heat load of the stove and the structure of the burner 2.

[0059] In another optional embodiment, the gas on / off actuator is a normally closed gas solenoid valve with an on / off response time ≤0.3s.

[0060] Normally closed gas solenoid valves are safety shut-off valves specifically designed for household gas stoves. In abnormal conditions such as power failure or control module malfunction, they can automatically remain closed to eliminate the risk of gas leakage.

[0061] In another optional embodiment, the abnormal combustion protection function on / off switch is a waterproof and oil-proof switch, which is connected in series with an LED status indicator. The LED status indicator is used to visually display the on / off status of the protection function controlled by the abnormal combustion protection function on / off switch. The control module adopts a microcontroller (such as a single-chip microcomputer), which has a built-in 12-bit AD sampling unit with a sampling frequency of 10 times / second, and has built-in multi-channel independent sampling channels matching the number of burners. Each NTC thermistor 1 is connected to an independent sampling channel.

[0062] Optionally, the preferred operating logic of the LED status indicator is as follows: it stays on when the abnormal combustion protection function is turned on, turns off when the function is turned off, and flashes as an alarm when abnormal combustion triggers the protection, thus realizing a visual prompt of the full function status.

[0063] Optionally, the multi-channel independent sampling channels, each channel uniquely corresponds to an NTC thermistor 1 of a burner. The sampling and calculation processes of each channel are completely independent and do not interfere with each other, which can avoid signal crosstalk when multiple burners 2 are working at the same time and ensure the accuracy of operating condition determination.

[0064] The protection function (firewall function) on / off switch is electrically connected to the control module. When the switch is turned on, the control module executes all the abnormal combustion protection logic of this invention. When the switch is turned off, the control module blocks the protection command output, and the stove returns to normal working state, which can adapt to the user's special cooking scenario needs. At the same time, the switch is connected in series with an LED status indicator to realize the visual display of the function's on / off status and ensure the accuracy of user operation.

[0065] Taking a household double-burner stove as an example, let's illustrate the electrical connection relationships of each module: Power module: It adopts an AC / DC power module with dual output of AC220V to DC3.3V / 5V. The AC input terminal is connected to the mains power, the DC3.3V output terminal is connected to the power supply pin of the control module, and the DC5V output terminal is connected to the power supply pin of the gas solenoid valve, LED indicator and function on / off switch. Temperature measurement module: The NTC thermistors of the left and right burners are connected at one end to the 3.3V reference voltage pin of the control module, and at the other end to the AD1 and AD2 independent sampling channel pins of the control module respectively. They are also grounded through a 10KΩ pull-down resistor, forming a voltage divider sampling circuit. Function on / off switch: One end is connected to the IO input pin of the control module, and the other end is connected to the DC5V power supply terminal. When the switch is closed, a high-level signal is input to the control module to enable the protection logic; when the switch is open, a low-level signal is input to disable the protection logic. LED indicator: The anode is connected to the DC5V power supply terminal after a 220Ω current-limiting resistor in series, and the cathode is connected to the IO output pin of the control module. The control module controls the on / off and flashing of the indicator by outputting high and low levels. Gas on / off control unit: It adopts a dual-path normally closed gas solenoid valve, which corresponds to the gas passage of the left and right burners respectively. The control terminal of the solenoid valve is connected to the output terminal of the MOS tube drive circuit of the control module. The control module controls the on / off of the solenoid valve through the drive circuit.

[0066] Example 3 Please see Figure 4 , Figure 4 This is a schematic diagram of the structure of a stove abnormal combustion condition judgment and control device disclosed in an embodiment of the present invention, including a memory 201, a processor 202 and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps in the method disclosed in Embodiment 1.

[0067] Example 4 This invention discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method disclosed in Embodiment 1.

[0068] The content disclosed in the embodiments of this invention is only a preferred embodiment of the invention and is used only to illustrate the technical solutions of the invention, not to limit it. Although the invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this invention.

Claims

1. A method for determining and controlling abnormal combustion conditions in a stove, characterized in that, Includes the following steps: (1) Function opening and closing judgment steps: The user's opening and closing instructions are received in real time through the abnormal combustion protection function opening and closing switch configured on the stove; when the closing instruction is received, all abnormal combustion protection control logic is blocked; when the opening instruction is received, the following steps (2) to (5) are executed. (2) Temperature acquisition steps: The temperature data of the corresponding burner area is collected in real time by the thermistor temperature sensor arranged on the burner head cover plate of each burner of the stove and located in the area between the outer ring fire cover and the center fire cover of the burner; the burner head cover plate is the upper sealing cover plate of the burner mixing chamber. (3) Real-time operating condition identification steps: operating condition is determined based on the collected temperature data; when the temperature of only a single burner is ≥ the preset effective combustion temperature threshold, it is determined to be a single burner operating condition; when the temperature of at least two burners is ≥ the effective combustion temperature threshold, it is determined to be a multi-burner operating condition; when the operating condition is switched, the judgment criteria for abnormal combustion are switched synchronously and automatically. (4) Abnormal combustion judgment steps: Based on the currently identified operating conditions, the corresponding differentiated judgment criteria are used to judge the abnormality. If any judgment condition is met, it is judged as an abnormal combustion state. Among them, the single burner operating condition is set with a first temperature rise slope judgment range and a first limit temperature threshold, and the multi-burner operating condition is set with a second temperature rise slope judgment range and a second limit temperature threshold. The temperature rise slope judgment is only activated when the collected temperature is ≥100℃. (5) Safety protection execution steps: When it is determined that the combustion state is abnormal, the control command is output to cut off the main gas passage of the stove.

2. The working condition determination and control method according to claim 1, characterized in that, In step (2), the burner cover is a flat metal mounting surface that comes with the burner and does not require additional openings. It is sealed and fitted with the combustion chamber of the burner, providing an installation reference for the outer ring burner cover, the center burner cover and the temperature sensor.

3. According to the working condition determination and control method of claim 1, in step (2), the thermistor temperature sensor is an NTC thermistor, whose temperature sensing surface is attached to the surface of the corresponding burner cover plate and is fixed by a high temperature resistant fixing structure to collect the radiation temperature of the corresponding burner area in a non-contact manner.

4. The working condition determination and control method according to claim 1, characterized in that, In step (3), the effective combustion temperature threshold is the lowest critical temperature that distinguishes between the burner standby state and the effective combustion state; and in step (4), the temperature rise slope is the ratio of the temperature change per unit time to the time, i.e., temperature rise slope = ΔT / Δt, where ΔT is the temperature change per unit time in K, and Δt is the preset unit time.

5. The working condition determination and control method according to claim 4, characterized in that, The preset unit time is 15 seconds; the baseline value of the effective combustion temperature threshold is 50°C.

6. The working condition determination and control method according to claim 5, characterized in that, In step (4): The first temperature rise slope determination range is: the detected temperature is in the range of 100℃~210℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~5K / 15s; the first extreme temperature threshold is 210℃. The second temperature rise slope determination range is: the detection temperature is in the range of 100℃~220℃, and the temperature rise slope in 15 seconds is in the range of 1K / 15s~6K / 15s; the second extreme temperature threshold is 220℃.

7. A stove, characterized in that, It includes the burner assembly, temperature measurement module, control module, gas on / off actuator, abnormal combustion protection function on / off switch, and power supply module; The burner assembly includes at least one independent burner, and each burner is provided with at least one NTC thermistor. The NTC thermistors constitute the temperature measurement module. The thermistor temperature sensor is arranged on the burner head cover plate of the corresponding burner and is located in the area between the outer ring fire cover and the center fire cover of the burner. The burner head cover plate is the upper sealing cover plate of the burner head mixing chamber. The abnormal combustion protection function on / off switch is fixed to the operating area of ​​the stove panel, and its signal output terminal is electrically connected to the IO pin of the control module. The gas on / off control unit is connected in series in the main gas passage of the stove, and its control terminal is electrically connected to the drive output terminal of the control module. The sampling input terminal of the control module is electrically connected to the signal output terminal of the temperature measurement module. The control module has a built-in differentiated anomaly determination logic unit corresponding to the single burner working condition and the multi-burner working condition respectively. The differentiated anomaly determination logic unit executes the control method according to any one of claims 1-6. The output terminal of the power module is electrically connected to the power supply terminals of the temperature measurement module, the control module, the gas on / off execution unit, and the abnormal combustion protection function on / off switch, respectively.

8. The stove according to claim 7, characterized in that, The burner head cover is a flat metal mounting surface that comes with the burner head. It is sealed to the combustion chamber of the burner head. A fixing lug is integrally provided on its side for fixing the burner head cover to the stove body. The thermistor temperature sensor is an NTC thermistor. Its temperature sensing surface is closely attached to the surface of the burner head cover and is fixed by a high-temperature resistant fixing structure.

9. The stove according to claim 7, characterized in that, The NTC thermistor has a temperature measurement range of -40℃ to 300℃, a response time of ≤0.5s, and a temperature measurement accuracy of ±1%; and the gas on / off actuator is a normally closed gas solenoid valve with an on / off response time of ≤0.3s.

10. The stove according to claim 7, characterized in that, The abnormal combustion protection function on / off switch is a waterproof and oil-proof switch, which is connected in series with an LED status indicator. The LED status indicator is used to visually display the on / off status of the abnormal combustion protection function on / off switch. The control module adopts a microcontroller, which has a built-in AD sampling unit and a multi-channel independent sampling channel matching the number of burners. Each NTC thermistor is connected to an independent sampling channel.

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