Cleaning method of range hood

Abstract

The invention discloses a cleaning method of a range hood, which comprises the following steps: entering a cleaning mode, starting a heating module, and controlling a water pump module to work according to a preset duty ratio; obtaining a theoretical heat energy threshold value required for melting oil dirt in the range hood main body; the actual effective heat energy added into the range hood body in an accumulated mode is obtained; and when the actual effective heat energy is larger than the theoretical heat energy threshold value and lasts for a set time, the heating module and the water pump module are closed, and the fan module is started. The problem that the cleaning energy efficiency of the range hood is low is solved.

Description

Technical Field

[0001] This application relates to the field of range hood technology, and in particular to a method for cleaning range hoods. Background Technology

[0002] Traditional high-temperature steam cleaning technology generally suffers from inherent drawbacks such as crude control, low energy efficiency, and unstable cleaning results. Most range hoods use a simple open-loop control mode of "heating + timed water intake," which cannot cope with complex operating conditions such as changes in ambient temperature, fluctuations in inlet water temperature, unstable voltage, and reduced heater efficiency. This leads to inconsistent cleaning results, either insufficient water leading to the danger of dry burning and energy waste, or excessive water resulting in insufficient steam vaporization rate, insufficient oil dissolving temperature, and ineffective cleaning, while consuming a large amount of water throughout the process. Summary of the Invention

[0003] This application aims to at least partially solve the problem of low energy efficiency in cleaning range hoods. To this end, the first aspect of this application provides a method for cleaning range hoods.

[0004] The cleaning method for a range hood provided above is achieved through the following technical solution:

[0005] A cleaning method for a range hood, the range hood comprising a main body, an acquisition module, a heating module, a water pump module, and a fan module, the cleaning method comprising the following steps: entering a cleaning mode, turning on the heating module, and controlling the water pump module to operate at a preset duty cycle; acquiring the theoretical heat energy threshold required to melt the grease inside the main body of the range hood; acquiring the cumulative actual effective heat energy input into the main body of the range hood; and when the actual effective heat energy is greater than the theoretical heat energy threshold and continues for a set time, turning off the heating module and the water pump module, and turning on the fan module.

[0006] In some embodiments, after the fan module is turned on, the cleaning method further includes the following steps: obtaining and determining whether the running time of the fan module is not less than the target time; if the running time is not less than the target time, restarting the water pump module; after the remaining water in the cleaning system is drained, turning off the fan module and the water pump module, and exiting the cleaning mode.

[0007] In some embodiments, the specific steps for obtaining the cumulative actual effective heat energy input into the main body of the flue gas hood include: obtaining the steam vaporization rate and the cumulative water inflow of the water pump module, and calculating the actual effective heat energy based on the steam vaporization rate and the cumulative water inflow; or obtaining the cumulative steam flow rate and calculating the actual effective heat energy based on the cumulative steam flow rate.

[0008] In some implementations, the actual effective thermal energy is calculated using the following formula: Q total =m va ×H v =(m 水 ×η)×H v In the formula, Q total For actual effective heat energy, m va To calculate the cumulative steam flow rate, H v For the latent heat of vaporization of water, m 水 The cumulative influent flow rate is η, and the steam vaporization rate is η.

[0009] In some embodiments, the specific steps for obtaining the cumulative inflow rate of the water pump module include: obtaining the preset duty cycle of the water pump module; and according to formula m 水 =Q max ×D calculates the influent flow rate, where Q max D is the rated flow rate of the water pump module at 100% duty cycle, and D is the preset duty cycle; the inlet flow rate is accumulated to obtain the cumulative inlet flow rate.

[0010] In some implementations, the preset duty cycle is obtained by: acquiring the inlet water temperature and acquiring the heating time required to heat the water from the inlet water temperature to the target temperature; calculating the preset duty cycle of the water pump module based on the inlet water temperature and the heating time; and controlling the water pump module to operate according to the preset duty cycle.

[0011] In some embodiments, the specific steps of controlling the water pump module to operate according to the preset duty cycle include: acquiring the temperature change trend of the water temperature; adjusting the preset duty cycle according to the temperature change trend; and controlling the water pump module to operate according to the adjusted preset duty cycle.

[0012] In some embodiments, the specific steps of calculating the preset duty cycle of the water pump module based on the inlet water temperature and the heating time include: obtaining the actual heating power by looking up a table or calculation based on the heating time; and calculating the preset duty cycle of the water pump module based on the inlet water temperature and the actual heating power.

[0013] In some implementations, the preset duty cycle is calculated using the following formula: In the formula, η is the target steam vaporization rate, and P u Q represents the actual heating power of the heating module. max Q is the rated flow rate of the pump module at 100% duty cycle. in D is the total influent flow rate, C is the preset duty cycle, and D is the total influent flow rate. p T is the specific heat capacity of water at constant pressure. b and T inThese represent the boiling point of water and the inlet water temperature, H. v It is the latent heat of vaporization of water.

[0014] In some embodiments, the specific steps for obtaining the theoretical thermal energy threshold required to melt the oil stains inside the range hood body include: obtaining the ambient temperature, the melting oil temperature, and the inherent parameters of the range hood body; calculating the temperature rise value between the melting oil temperature and the ambient temperature; calculating the mass of injected steam required to melt the oil stains based on the temperature rise value and the inherent parameters; and calculating the theoretical energy threshold required to melt the oil stains inside the range hood body based on the mass of injected steam.

[0015] In some embodiments, the mass of the injected steam is calculated using the following formula: m s ×h s =m i ×c i ×ΔT+m b ×c b ×ΔT, where m s For the mass of the injected steam, h s For vapor specific enthalpy, m i c i The specific heat capacity of air at constant pressure is given by m, where ΔT is the temperature rise from ambient temperature to melting oil temperature. b c is the total mass of the metal parts inside the main body of the range hood. b This represents the specific heat capacity of the steel plate.

[0016] In some embodiments, before turning on the heating module and controlling the water pump module to operate at a preset duty cycle, the cleaning method further includes the following steps: turning on the water pump module and simultaneously starting to record the pumping time; determining whether the pumping time has reached the preset pumping time; when the pumping time reaches the preset pumping time, obtaining the inlet water temperature of the cleaning system; turning off the water pump module and turning on the heating module to heat the water from the inlet water temperature to the target temperature.

[0017] Compared with the prior art, this application has at least the following beneficial effects:

[0018] This application provides a cleaning method for a range hood. By first melting the grease inside the range hood body to the theoretical heat energy threshold, and when the cumulative actual effective heat energy input exceeds the theoretical heat energy threshold for a set time, the heating module and water pump module are turned off, and the fan module is turned on. The cleaning time is short and the efficiency is high. This enables the range hood to have a grease melting prediction function, which can adaptively and dynamically match the cleaning water volume. The steam generation process is transformed from a "black box" operation into a "white box" optimization process, ultimately achieving efficient, energy-saving, and adaptive intelligent cleaning. Attached Figure Description

[0019] Figure 1The connection block diagram of the range hood in this embodiment is shown;

[0020] Figure 2 The flowchart of the cleaning method in this embodiment is shown. Figure 1 ;

[0021] Figure 3 The flowchart of the cleaning method in this embodiment is shown. Figure 2 .

[0022] In the diagram: 1-Main body of the range hood, 11-Outer shell assembly, 12-Box assembly; 2-Main control module; 3-Acquisition module, 31-Temperature sensor, 32-Timer; 4-Heating module, 41-Heating element, 42-Heating channel; 5-Water pump module; 6-Fan module. Detailed Implementation

[0023] The following embodiments illustrate this application, but this application is not limited to these embodiments. Modifications to the specific implementation of this application or equivalent substitutions for some technical features, without departing from the spirit of this application, should all be covered within the scope of the technical solution claimed in this application.

[0024] refer to Figure 1 This embodiment provides a cleaning method for a range hood. The range hood includes a main body 1, a main control module 2, and a cleaning system. The main body 1 includes a shell assembly 11 and a housing assembly 12 installed on top of the shell assembly. The main control module 2 is installed on the main body 1, preferably on top of the housing assembly 12. The cleaning system includes an acquisition module 3, a heating module 4, a water pump module 5, and a fan module 6 installed inside the housing assembly 12. The acquisition module includes a temperature sensor 31 and a timer 32. The temperature sensor 31 is disposed on the heating module 4 and electrically connected to the main control module 2, and is used to detect the ambient temperature and the inlet water temperature of the heating module 4. This allows for the measurement of temperature parameters affecting steam output, such as ambient temperature and inlet water temperature, using only one temperature sensor in conjunction with an intelligent algorithm, thereby reducing costs. The timer 32 is electrically connected to the main control module and is used to record the heating time of the heating module 4 and the pumping time of the water pump module 5. This allows the actual heating power, heat loss rate and other working parameters that affect steam output to be measured using only one temperature sensor and the timer 32.

[0025] The heating module 4 is preferably a steam generator mounted on the main body of the range hood. This steam generator includes a heating element 41 and a heating channel 42. The inlet of the heating channel 42 is connected to tap water or a cleaning water tank via a water pump module 5. The outlet of the heating channel 42 is connected to a nozzle assembly mounted on the fan module 6. The nozzle assembly sprays the cleaning medium into the fan module to clean it. A temperature sensor 31 is installed on the heating channel 42 to detect the ambient temperature and the inlet water temperature. The heating element 41 heats the water in the heating channel 42 to a target temperature higher than the boiling point of water, thus providing high-temperature steam to the fan module, enabling the range hood to have a steam cleaning function for efficient cleaning. The water pump module 5 may include only an inlet pump, or it may include both an inlet pump and a drain pump. The inlet pump can be configured to pump water into the heating channel of the heating module, and the drain pump can be configured to drain the water stored in the water tank assembly and / or the heating channel of the heating module. When the water pump module 5 includes only an inlet pump, the inlet pump can be controlled to rotate in both directions to have both inlet and drain functions. When the inlet pump rotates in the forward direction, it can deliver water into the heating channel; conversely, when the inlet pump rotates in the reverse direction, it can drain the water stored in the heating channel to prevent water accumulation in the heating channel from forming troughs and breeding bacteria.

[0026] refer to Figure 2-3 The cleaning method includes the following steps:

[0027] A1, enter cleaning mode, turn on the heating module, and control the water pump module to work according to the preset duty cycle;

[0028] Specifically, the range hood's cleaning mode includes a cleaning preparation stage, a steam oil-dissolving cleaning stage, and an oil-removing stage. When entering the cleaning mode, it first enters the cleaning preparation stage, then the steam oil-dissolving cleaning stage, and finally the oil-removing stage. When the range hood enters the cleaning preparation stage, it first obtains the ambient temperature through a temperature sensor, then turns on the water pump module 5 and turns off the heating module 4. At this time, only water enters, but no heating is performed to prevent the heating module from dry burning due to lack of water. The water pump module 5 delivers water to the heating channel of the heating module so that the water can flow through the temperature sensor 31. At this time, the temperature sensor 31 detects the water temperature in the heating channel. This water temperature is at room temperature and its magnitude is positively correlated with the ambient temperature. Then, the water pump module 5 is turned off and the heating module 4 is turned on to heat the water to the target temperature (e.g., 110°C), and then it enters the steam oil-dissolving cleaning stage.

[0029] In step A1, the specific steps of entering the cleaning mode, turning on the heating module, and controlling the water pump module to work according to the preset duty cycle include: entering the steam oil dissolving cleaning stage of the cleaning module, turning on the heating element 41 of the heating module 4, and controlling the water pump module 4 to work according to the preset duty cycle. In the current stage, the heating module continues to work, and the water pump module 4 works according to the preset duty cycle and sprays water periodically to continuously inject steam into the fan module 6, using the steam to heat the fan module 6 and the housing assembly 12 to the temperature at which the oil stains melt.

[0030] The cumulative water volume can be obtained by counting the water volume sprayed by the water pump module in multiple consecutive cycles.

[0031] A2, obtain the theoretical thermal energy threshold required to melt the oil stains inside the main body of the range hood;

[0032] Specifically, after the range hood enters the steam oil-dissolving cleaning stage, the theoretical heat energy threshold Q required to melt the oil stains inside the range hood body is obtained. melt At this time, the oil stains inside the main body of the range hood can be oil stains inside the fan module, or oil stains inside the fan module and the housing assembly 12.

[0033] A3, Obtain the cumulative actual effective heat energy Q invested in the main body of the smoke machine. total ;

[0034] A4. When the actual effective heat energy is greater than the theoretical heat energy threshold and continues for a set time, shut down the heating module and water pump module, and turn on the fan module.

[0035] Specifically, when the actual effective heat energy exceeds the theoretical heat energy threshold, it indicates that sufficient steam has been injected into the main body of the range hood, heating the chamber temperature to above the melting oil temperature. At this point, the oil stains inside the chamber components are melted by the steam. By continuously setting the time (e.g., 60 seconds or more), the oil stains are completely melted. Then, the heating module 4 and water pump module 5, along with the fan module 6, are activated to remove the oil. This maximizes the removal of oil stains from the fan module 6, effectively cleaning the chamber. If the chamber temperature does not reach the melting oil temperature, the oil stains are difficult to remove by removing the oil. If the chamber temperature is much higher than the melting oil temperature, although the oil stains can be removed, the improvement in cleanliness is minimal, and the excess temperature results in a waste of electricity and water. Therefore, activating the oil removal function after the chamber temperature reaches the melting oil temperature and remains there for the set time balances cleanliness and energy consumption.

[0036] As can be seen, the cleaning method for a range hood proposed in this application first melts the grease inside the main body of the range hood using the theoretical heat energy threshold required. Then, when the accumulated actual effective heat energy exceeds the theoretical heat energy threshold for a set time, the heating module and water pump module are shut off, and the fan module is turned on. This results in a short cleaning time and high efficiency, enabling the range hood to have an oil melting prediction function. The core of this prediction is to accurately estimate the preheating state of the cabinet components through a heat energy accumulation algorithm, thereby completely eliminating the reliance on physical temperature sensors and achieving the goal of "minimal water use, lowest energy consumption, and rapid oil dissolution." This cleaning method can adaptively and dynamically match the cleaning water volume, transforming the steam generation process from a "black box" operation into a "white box" optimization process, ultimately achieving efficient, energy-saving, and adaptive intelligent cleaning.

[0037] refer to Figure 3 Furthermore, after turning on the fan module, the cleaning method also includes the following steps:

[0038] A51, obtain and determine whether the running time of the wind turbine module is not less than the target time;

[0039] Specifically, the blower module operates at the target setting, and simultaneously, a timer begins recording the blower module's operating time, i.e., the oil-scraping time. The target setting can be high or medium, but high setting is preferred to improve the oil-scraping effect.

[0040] A52, when the running time is not less than the target time, restart the heating module and water pump module;

[0041] Specifically, the target time can be 60 seconds or more. When the oil removal time (the running time of the fan module) is not less than the target time, the heating module and water pump module are restarted. At this time, the fan module can operate at the target speed or at other operating speeds. While restarting the water pump module, the heating module can remain off or restart simultaneously. By restarting the water pump module, it is easier to spray all the remaining water onto the fan module 6, achieving the purpose of cleaning residual oil stains with residual water.

[0042] A53: After draining the remaining water from the cleaning system, turn off the fan module and water pump module to exit the cleaning mode. Specifically, draining the remaining water can be done by draining the remaining water from the heating module or the water tank assembly, to utilize the remaining water for rinsing while preventing residual water from breeding bacteria in the cleaning system. If the heating module is turned on in step A52, then the heating module will be turned off in step A53.

[0043] refer to Figure 3 Furthermore, in step A1, before turning on the heating module and controlling the water pump module to operate at a preset duty cycle, the cleaning method also includes the following steps:

[0044] A10, obtain the ambient temperature;

[0045] Specifically, when the range hood enters the cleaning mode, it first enters the cleaning preparation stage, and the initial temperature in the heating channel is detected by the temperature sensor 31 of the acquisition module. This initial temperature is used as the ambient temperature.

[0046] A11, turn on the water pump module and start recording the pumping time;

[0047] Specifically, the water pump module 5 is turned on and the heating module 4 is turned off. At this time, only water is introduced, but no heating is performed to prevent the heating module from dry burning due to lack of water. The water pump module 5 delivers water to the heating channel of the heating module so that the water can flow through the temperature sensor 31. At the same time as the water pump module is turned on, the timer starts pumping water and starts recording the pumping time.

[0048] In addition, before the water pump module 5 pumps water to the heating channel of the heating module, the water pump module 5 can be used to drain the water in the heating channel to prevent inaccurate water flow due to water in the heating channel. At this time, the drain pump of the water pump module 5 can be used to drain the water in the heating channel, or the water pump of the water pump module 5 can be reversed until it runs dry to drain the water in the heating channel.

[0049] A12, determine whether the pumping time has reached the preset pumping time;

[0050] A13, when the pumping time reaches the preset pumping time, obtain the inlet water temperature of the cleaning system;

[0051] Specifically, the main control module continuously determines whether the pumping time has reached the preset pumping time. If the pumping time has not reached the preset pumping time, step A12 is executed. If the pumping time has reached the preset pumping time, the inlet water temperature of the cleaning system is acquired, i.e., the inlet water temperature in the heating channel is detected by the temperature sensor 31 of the acquisition module. The preset pumping time is 3-10s, and can be any of 3s, 4s, 5s, 6s, 7s, 8s, or 9s. The length of the preset pumping time is positively correlated with the inlet water volume and negatively correlated with the steam output rate. Manufacturers or users can set it according to specific requirements. It can be seen that by using a single temperature sensor 31, combined with an intelligent algorithm, temperature parameters affecting steam output, such as ambient temperature and inlet water temperature, can be measured. In addition, when the pumping time reaches the preset pumping time, such as when the pumping time is ≥3s, ensure that the water flows through the temperature sensor position and fills the heating channel. Read the temperature at this time as the inlet water temperature. By detecting the inlet water temperature after a period of time, the influence of unstable factors on temperature detection can be reduced, which helps to improve the accuracy of inlet water temperature detection.

[0052] A14, turn off the water pump module and turn on the heating module to heat the water from the inlet temperature to the target temperature.

[0053] Specifically, after obtaining the inlet water temperature of the cleaning system, the water pump module is turned off and the heating module is turned on. The heating time required to heat the water from the inlet water temperature to the target temperature is obtained. At this time, the main control module can calculate the preset duty cycle of the water pump module based on the inlet water temperature and heating time using a formula. After calculating the preset duty cycle of the water pump module, the range hood enters the steam oil dissolving cleaning stage. At this time, the main control module controls the range hood to perform the above steps A1-A4. The target temperature is higher than the boiling point of water, with a target temperature of 105-120℃, preferably 110℃. By turning off the water pump module and turning on the heating module, the water in the heating module can be heated up quickly.

[0054] In A14, the specific steps for heating water from the inlet temperature to the target temperature include: starting a heating timer simultaneously with turning on the heating module; acquiring and determining whether the real-time water temperature is not lower than the target temperature; and acquiring the heating time required to raise the water temperature from the inlet temperature to the target temperature when the real-time water temperature is not lower than the target temperature. In this embodiment, the timer 32 of the acquisition module starts a heating timer simultaneously with turning on the heating module, recording the heating time required to raise the water in the heating module from the inlet temperature to the target temperature. Simultaneously or subsequently, the temperature sensor 31 of the acquisition module collects temperature data at 100ms intervals (or 50ms, 150ms, or 200ms), and sends the temperature data to the main control module. The main control module obtains the real-time water temperature based on the temperature data and compares it with the target temperature. When the real-time water temperature is ≥ the target temperature, it indicates that the water in the heating channel has been heated to vaporization. At this time, the heating module produces high-temperature steam, and the timer is read to obtain the heating time required to raise the water temperature from the inlet temperature to the target temperature. The main control module 2 can calculate the current actual heating power based on heating time, historical data (such as lookup table method), or calculation formula. During the heat loss assessment stage, it can calculate the heat loss rate based on the actual heating power and the theoretical heating power. This method automatically compensates for the impact of grid voltage fluctuations and changes in heating module performance. In addition, the main control module can also calculate the preset duty cycle of the water pump module 5 based on the inlet water temperature and heating time.

[0055] Furthermore, the specific steps for calculating the preset duty cycle of the water pump module based on the inlet water temperature and heating time include: obtaining the actual heating power by looking up a table or calculation based on the heating time; and calculating the preset duty cycle of the water pump module based on the inlet water temperature and the actual heating power.

[0056] Specifically, the system pre-stores the heating time Δt and the actual heating power P. u Relationships, for example, Δt = 20s, P u=600W; Δt=18s, P u =570W; Δt=22s, P u =620W. Once the heating time required to heat the water from the inlet temperature to the target temperature is obtained, the actual heating power can be calculated using a lookup table. This method automatically compensates for the effects of grid voltage fluctuations and heater performance variations. Alternatively, the actual heating power, P, can also be calculated. u = (1-K)×P i Where K is the heat loss rate, P i P represents the total input power of the heating module. i K is a fixed value, which can be obtained by looking up a table or by calculation. In the heat loss assessment stage, the heat loss rate is calculated by the ratio of the actual heating power to the theoretical heating power.

[0057] Specifically, the preset duty cycle is calculated using the following formula:

[0058]

[0059] In the formula, η is the target steam vaporization rate, and P u Q represents the actual heating power (W) of the heating module. max D represents the rated flow rate (kg / s) of the pump module at 100% duty cycle, and C represents the preset duty cycle (%). p The specific heat capacity of water at constant pressure (J / (kg·℃)), T b and T in H represents the boiling point of water (°C) and the inlet water temperature (°C), respectively. v The latent heat of vaporization of water (J / kg).

[0060] In this cleaning system, Q max C p T b H v For a fixed value, P u T i The cleaning efficiency is affected by environmental factors and is therefore variable. To improve cleaning efficiency, the current working environment needs to be measured, and the target steam vaporization rate η needs to be approached 100% by controlling the water inlet flow rate. This ensures that all water is converted into steam for oil melting, thus maximizing cleaning efficiency. In this embodiment, the target steam vaporization rate η can approach 100%, but it can also be designed to be lower than 100%, for example, η∈[80%,100%), meaning η can be 85%, 90%, or 95%. At this point, the preset duty cycle of the water pump module is calculated according to the formula. Thus, the cleaning preparation stage is completed, and the process moves to the next stage, namely the steam oil melting cleaning stage.

[0061] Additionally, the preset duty cycle can also be achieved through... Calculated. In In the formula, η is the target steam vaporization rate, and Q max Q is the rated flow rate of the pump module at 100% duty cycle. in D represents the inlet water flow rate, and D represents the preset duty cycle. The inlet water flow rate is controlled by adjusting the preset duty cycle of the water pump module. By acquiring the inlet water flow rate through the acquisition module and combining it with the core control target (i.e., steam vaporization rate), the preset duty cycle of the water pump module can be calculated.

[0062] The above formulas reveal all the key variables affecting steam generation efficiency and their interrelationships: P u As an energy source; the heat loss rate K, as the system's "efficiency killer," is directly proportional to the inlet water temperature of the heating channel and the ambient temperature difference. Dry burning will cause it to increase sharply, reducing the energy available for vaporization; inlet water flow rate Q in As a core control variable, it is inversely proportional to the gasification rate η. Although reducing the flow rate can increase the gasification rate, dry burning must be strictly avoided; the inlet water temperature T i As an environmental variable, low winter temperatures increase the actual heat required to heat water to its boiling point, significantly reducing steam output. Therefore, the system needs to sense the inlet water temperature and adjust its strategy accordingly, i.e., calculate the ideal inlet water flow rate and determine the rated flow rate of the pump module as Q. max This is converted to control the duty cycle, thereby enabling precise control of the water pump module during the working phase.

[0063] Specifically, after calculating the preset duty cycle of the water pump module, the system transitions to the steam oil-dissolving cleaning stage. At this stage, the main control module activates the heating module and controls the water pump module to operate according to the preset duty cycle. The specific steps for controlling the water pump module to operate according to the preset duty cycle include: acquiring the water temperature change trend; adjusting the preset duty cycle based on the temperature change trend; and controlling the water pump module to operate according to the adjusted preset duty cycle. This improves the self-adaptability of the cleaning system, compensating for the impact of grid voltage fluctuations, performance changes in the heating module and water pump module, etc. In the steam oil-dissolving cleaning stage, the temperature change trend detected by the temperature filtering algorithm can be combined.

[0064] Specifically, after the range hood enters the steam oil-dissolving cleaning stage, the temperature curve fluctuates drastically due to the temperature sensor being located in the heating channel and the periodic operation of the water pump module. When water pump module 5 operates, the inflow of cold water causes a momentary drop in temperature within the heating channel 42; after the water evaporates, the continuous heating by heating module 4 causes a rapid rise in temperature within the heating channel 42. To accurately capture the essence of temperature changes, a temperature filtering algorithm is used to detect the temperature trend. This algorithm is as follows: the interval between two water sprays from water pump module 4 is considered a calculation cycle. At the end of the first spray, the inlet water temperature is lowest, and before the second spray, the inlet water temperature is highest. The time and average temperature of this cycle are statistically analyzed. By continuously statistically analyzing the values ​​for several calculation cycles, the average heating rate of the current stage can be obtained. This method effectively avoids interference from instantaneous fluctuations and can reliably identify the true trend of temperature changes.

[0065] After the temperature change trend is detected using a temperature filtering algorithm, the main control module adjusts the preset duty cycle of the water pump module according to the temperature change trend. If the temperature change trend is zero, it indicates that the temperature remains unchanged, and the preset duty cycle is not adjusted; the water pump module is controlled to operate according to the original preset duty cycle. If the temperature change trend increases, the preset duty cycle is increased, and the water pump module is controlled to operate according to the increased preset duty cycle. If the temperature change trend decreases, the preset duty cycle is decreased, and the water pump module is controlled to operate according to the decreased preset duty cycle. This achieves adaptive and intelligent adjustment of the water pump module's spray volume based on the temperature change trend, i.e., controlling the water pump module's spray volume based on the actual detected temperature change trend. This allows the steam generator to maximize the steam vaporization rate without dry burning, ultimately achieving efficient, safe, water-saving, and adaptive intelligent cleaning.

[0066] The average heating rate R is an extremely sensitive state indicator. During normal vaporization, the temperature reaches dynamic equilibrium slightly above the boiling point, at which point R≈0, indicating that the temperature change trend is zero. When the water volume is slightly low, the temperature shows a slow upward trend, at which point R>0, indicating that the temperature change trend is increasing. When there is a risk of dry burning, the temperature rises sharply, at which point R>>0.

[0067] In this embodiment, if R remains above a positive threshold, it indicates insufficient water in the cleaning system and a tendency for dry burning, confirming an increasing temperature trend. In this case, the main control module increases the preset duty cycle and controls the water pump module according to the increased preset duty cycle to make pumping or spraying water more frequent, increasing the water intake to enhance cooling. If R stabilizes near zero, it indicates the system is in optimal operating condition, confirming a zero temperature trend. In this case, the preset duty cycle is maintained, i.e., the preset duty cycle is not adjusted, and the water pump module is controlled according to the original preset duty cycle. If R is negative, it indicates excessive water intake and a low vaporization rate, confirming a decreasing temperature trend. In this case, the main control module decreases the preset duty cycle and controls the water pump module according to the decreased preset duty cycle to reduce the pumping or spraying frequency and decrease the water intake to enhance vaporization. Through this adaptive control based on trend prediction, the cleaning system can continuously fine-tune the preset duty cycle of the water pump module, so that the vaporization rate of its output steam approaches the theoretical optimal value of 100%, thereby dynamically maintaining the most efficient and safest working state.

[0068] Furthermore, in step A2, the specific steps for obtaining the theoretical thermal energy threshold required to melt the grease inside the range hood body include:

[0069] A21, obtain ambient temperature, melting oil temperature and inherent parameters of the main body of the range hood;

[0070] Specifically, the ambient temperature, melting oil temperature, and inherent parameters of the main body of the range hood are actually detected through step A10 above and pre-stored in the main control module of the range hood. The relevant data can be obtained by retrieving them.

[0071] A22, calculate the temperature rise of the molten oil temperature relative to the ambient temperature;

[0072] A23, based on the temperature rise and inherent parameters, calculate the mass of injected steam required to melt the oil.

[0073] Specifically, according to the law of conservation of energy, the heat brought in by the injected steam = the heat absorbed by the temperature rise of the gas inside the main cavity of the range hood + the heat absorbed by the temperature rise of the components (mainly sheet metal parts) inside the main cavity of the range hood, where the mass of the injected steam is calculated using the following formula: m s ×h s =m i ×c i ×ΔT+m b ×c b ×ΔT, where m s For the mass of injected steam (Kg), h s For the specific enthalpy of steam (100℃ water vapor ≈ 2676 KJ / Kg), m i The original air mass (kg) inside the main body of the range hood, c iΔT is the specific heat capacity of air at constant pressure (≈1.005 KJ / (Kg*K)), ΔT is the temperature rise (°C) from ambient temperature to melting oil temperature, and m b c is the total mass (kg) of the metal parts inside the main body of the range hood. b The specific heat capacity of the steel plate is approximately 0.46 kJ / (kg*K).

[0074] Among them, h s c i and c b Both are constants, m i and m b For each range hood, a fixed value is provided; ΔT is related to the current ambient temperature, m. s This is a value that can be controlled programmatically. During use, the m value for each type of range hood is first calculated based on its structure. i and m b The value is then calculated by detecting the ambient temperature and determining ΔT at the start of each cleaning cycle, thus obtaining the desired final result m. s .

[0075] A24. Based on the mass of the injected steam, calculate the theoretical energy threshold required to melt the oil stains inside the main body of the range hood.

[0076] Specifically, the theoretical thermal energy threshold is calculated using the following formula: m s =Q melt ×ρ×t, where Q melt The theoretical energy threshold required to melt oil contamination, m s For the mass of the injected steam, h s Let ρ be the specific enthalpy of the steam, ρ be the density of the injected steam, and t be the steam injection time. Therefore, the cleaning system can accurately predict the thermal state within the chamber components without any chamber temperature sensors, fundamentally solving traditional problems such as sensor response delay, installation location limitations, and reliability issues. It is evident that the core of the oil melting prediction system is to accurately estimate the preheating state of the chamber through a thermal energy accumulation algorithm, thereby completely eliminating reliance on physical temperature sensors and achieving the goal of "minimal water use, lowest energy consumption, and rapid oil melting."

[0077] Furthermore, in step A3, the specific steps for obtaining the cumulative actual effective thermal energy input into the main body of the flue gas hood include: obtaining the steam vaporization rate η and the cumulative water inflow rate m of the water pump module. 水 Based on the steam vaporization rate and the cumulative influent flow rate (m³) 水 The actual effective heat energy is calculated. Alternatively, the specific steps for obtaining the cumulative actual effective heat energy input into the main body of the flue gas fan include: obtaining the cumulative steam flow rate m. va Based on the cumulative steam flow rate m va The actual effective thermal energy is calculated.

[0078] Specifically, by integrating the preset duty cycle D of the water pump module over time, the cumulative inflow rate m can be accurately calculated. 水 By combining the actual heating power P of the heating module u and inlet water temperature T i The cumulative steam volume m is dynamically calculated and integrated. va The actual effective thermal energy is calculated using the following formula: Q total =m va ×H v =(m 水 ×η)×H v In the formula, Q total For actual effective heat energy, m va To calculate the cumulative steam flow rate, H v For the latent heat of vaporization of water, m 水 The cumulative influent flow rate is η, and the steam vaporization rate is η.

[0079] When Q total Greater than Q melt If the oil stains are completely melted after 60 seconds of continuous operation, the fan module is immediately controlled to spray oil at the highest setting for 60 seconds. At this time, the oil stains on the impeller of the fan module 6 can be sprayed off to the maximum extent. Finally, the water pump module 5 is turned on to spray all the remaining water onto the impeller of the fan module 6, so as to achieve the purpose of cleaning the residual oil stains with water.

[0080] Specifically, obtain the cumulative inflow rate m of the water pump module. 水 The specific steps include: obtaining the preset duty cycle of the water pump module; and according to the formula m 水 =Q max ×D calculates the influent flow rate, where Q max The rated flow rate of the water pump module at 100% duty cycle is given by D, where D is the preset duty cycle; the cumulative inlet flow rate is obtained by accumulating the inlet flow rate m. 水 This allows for accurate calculation of the cumulative inflow rate (m) by integrating the preset duty cycle D of the water pump module over time. 水 .

[0081] In summary, the core advantage of this cleaning method lies in its decision-making based on energy input rather than physical temperature monitoring. This fundamentally avoids problems such as sensor measurement errors, response delays, and installation location limitations, achieving true "sensorless precise temperature control" and "minimum water preheating." The energy invested by this system is precisely used for preheating the tank and melting oil stains, maximizing water and electricity savings and significantly reducing hardware costs and system complexity.

[0082] The above are merely some embodiments of this application. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this application, and these all fall within the protection scope of this application.

Claims

1. A method for cleaning a range hood, characterized in that, The range hood includes a main body, a data acquisition module, a heating module, a water pump module, and a fan module. The cleaning method includes the following steps: Enter cleaning mode, turn on the heating module, and control the water pump module to work according to a preset duty cycle; Obtain the theoretical thermal energy threshold required to melt the oil stains inside the main body of the range hood; Obtain the cumulative actual effective heat energy invested in the main body of the smoke machine; When the actual effective thermal energy is greater than the theoretical thermal energy threshold and continues for a set time, the heating module and the water pump module are turned off, and the fan module is turned on.

2. The cleaning method for a range hood according to claim 1, characterized in that, After the fan module is turned on, the cleaning method further includes the following steps: Obtain and determine whether the running time of the fan module is not less than the target time; The water pump module will be restarted when the running time is not less than the target time. After the remaining water in the cleaning system is drained, the fan module and the water pump module are turned off, and the cleaning mode is exited.

3. The cleaning method for a range hood according to claim 1, characterized in that, The specific steps for obtaining the cumulative actual effective heat energy invested within the main body of the range hood include: Obtain the steam vaporization rate and the cumulative inlet water flow rate of the water pump module, and calculate the actual effective thermal energy based on the steam vaporization rate and the cumulative inlet water flow rate; or Obtain the cumulative steam flow rate, and calculate the actual effective thermal energy based on the cumulative steam flow rate.

4. The cleaning method for a range hood according to claim 3, characterized in that, The actual effective thermal energy is calculated using the following formula: Q total =m va ×H v =(m 水 ×η)×H v , In the formula, Q total For actual effective heat energy, m va To calculate the cumulative steam flow rate, H v For the latent heat of vaporization of water, m 水 The cumulative influent flow rate is η, and the steam vaporization rate is η.

5. A cleaning method for a range hood according to claim 3 or 4, characterized in that, The specific steps for obtaining the cumulative inflow rate of the water pump module include: Obtain the preset duty cycle of the water pump module; According to formula m 水 =Q max ×D calculates the influent flow rate, where Q max D represents the rated flow rate of the pump module at 100% duty cycle, where D is the preset duty cycle. The influent flow rate is accumulated to obtain the cumulative influent flow rate.

6. A cleaning method for a range hood according to claim 1 or 5, characterized in that, The preset duty cycle is obtained in the following way: Obtain the inlet water temperature and the heating time required to heat the water from the inlet water temperature to the target temperature; Calculate the preset duty cycle of the water pump module based on the inlet water temperature and the heating time; The water pump module is controlled to operate according to the preset duty cycle.

7. A cleaning method for a range hood according to claim 6, characterized in that, The specific steps for controlling the water pump module to operate according to the preset duty cycle include: To obtain the temperature change trend of the water; The preset duty cycle is adjusted according to the temperature change trend, and the water pump module is controlled to work according to the adjusted preset duty cycle.

8. A cleaning method for a range hood according to claim 6, characterized in that, The specific steps for calculating the preset duty cycle of the water pump module based on the inlet water temperature and the heating time include: Based on the heating time, the actual heating power is obtained by looking up a table or by calculation. The preset duty cycle of the water pump module is calculated based on the inlet water temperature and the actual heating power.

9. A cleaning method for a range hood according to claim 8, characterized in that, The preset duty cycle is calculated using the following formula: In the formula, η is the target steam vaporization rate, and P u Q represents the actual heating power of the heating module. max Q is the rated flow rate of the pump module at 100% duty cycle. in D is the total influent flow rate, C is the preset duty cycle, and D is the total influent flow rate. p T is the specific heat capacity of water at constant pressure. b and T in These represent the boiling point of water and the inlet water temperature, H. v It is the latent heat of vaporization of water.

10. A cleaning method for a range hood according to claim 1, characterized in that, The specific steps for obtaining the theoretical thermal energy threshold required to melt the grease inside the range hood body include: Obtain ambient temperature, melting oil temperature, and inherent parameters of the main body of the range hood; Calculate the temperature rise of the molten oil relative to the ambient temperature; Based on the temperature rise value and the inherent parameters, the mass of injected steam required to melt the oil stains is calculated; Based on the mass of the injected steam, calculate the theoretical energy threshold required to melt the oil stains inside the main body of the smoke machine.

11. A cleaning method for a range hood according to claim 10, characterized in that, The mass of the injected steam is calculated using the following formula: m s ×h s =m i ×c i ×ΔT+m b ×c b ×ΔT, In the formula, m s For the mass of the injected steam, h s For vapor specific enthalpy, m i c i The specific heat capacity of air at constant pressure is given by m, where ΔT is the temperature rise from ambient temperature to melting oil temperature. b c is the total mass of the metal parts inside the main body of the range hood. b This represents the specific heat capacity of the steel plate.

12. A cleaning method for a range hood according to claim 1, characterized in that, Before activating the heating module and controlling the water pump module to operate at a preset duty cycle, the cleaning method further includes the following steps: Turn on the water pump module and start recording the pumping time simultaneously; Determine whether the pumping time has reached the preset pumping time; When the pumping time reaches the preset pumping time, the inlet water temperature of the cleaning system is obtained; The water pump module is turned off and the heating module is turned on to heat the water from the inlet temperature to the target temperature.

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