Condensate water prevention device for smoke barrier of intelligent range hood and control method

Abstract

The invention discloses a smoke barrier condensate water prevention device of an intelligent extractor hood and a control method, and the smoke barrier condensate water prevention device of the intelligent extractor hood comprises a smoke barrier; the smoke barrier comprises a glass panel; the condensate water prevention device for the smoke barrier further comprises a heating film layer and a PVDF piezoelectric film layer which are arranged on the inner surface of the glass panel, the heating film layer is tightly attached to the glass panel, the PVDF piezoelectric film layer covers the side, away from the glass panel, of the heating film layer, and the whole formed by the heating film layer and the PVDF piezoelectric film layer is divided into n independent units.

Description

Technical Field

[0001] This invention relates to smart kitchen appliances, and more particularly to a smoke baffle anti-condensation device for a smart range hood, a smart range hood using the smoke baffle anti-condensation device, as well as a water droplet recognition method and a smoke baffle anti-condensation control method for the smart range hood. Background Technology

[0002] Range hoods have become an indispensable kitchen appliance in modern homes. They operate on the principles of fluid dynamics, using a fan system installed inside to draw in and exhaust cooking fumes, and a filter to remove some of the grease particles.

[0003] To improve smoke collection, range hoods are typically equipped with smoke deflectors. Cooking gases generally contain moisture in addition to oil fumes, especially during steaming or boiling, which produces a lot of steam. Water droplets easily condense on the lower surface of the smoke deflector (steaming generates more moisture than frying or stir-frying, and users generally choose medium or low settings for steaming due to lower airflow and noise levels, while frying or stir-frying uses higher settings). Since range hoods are installed above the cooktop and pots, the rising fumes and moisture easily condense on the glass and metal surfaces of the smoke deflector. These water droplets can drip into the pots, affecting the user experience (some users even feel the food is unclean upon seeing water droplets in the pot), or condense on the smoke deflector or control panel (some control areas are integrated into the smoke deflector), affecting button operation.

[0004] Therefore, there is a range hood, such as the range hood disclosed in Chinese Patent Application No. 202022736959.5, which is a top-mounted range hood and includes a smoke collection hood and a smoke gathering plate. The bottom of the smoke collection chamber of the smoke collection hood is provided with a smoke inlet. The smoke gathering plate covers the smoke inlet and can be flipped outwards. The smoke gathering plate is provided with a heating element, which is configured to heat the rear wall of the smoke gathering plate when it is flipped out. The smoke gathering plate is a hollow sandwich plate and the heating element is provided in the sandwich cavity.

[0005] The existing range hoods described above, by incorporating heating elements installed within the hollow cavity of the smoke-collecting plate, achieve both anti-condensation and prevent direct contact with high-temperature steam, thus extending their service life and allowing for a more compact structure. However, they lack the ability to detect condensate and cannot remove it as needed. Summary of the Invention

[0006] The first technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a condensation prevention device for the smoke baffle of an intelligent range hood, in which the heating module is reused to detect and remove condensation, thereby simplifying the structure.

[0007] The second technical problem to be solved by the present invention is to provide an intelligent range hood that uses the above-mentioned smoke baffle anti-condensation device.

[0008] The third technical problem to be solved by the present invention is to provide a method for water droplet recognition in the above-mentioned intelligent range hood.

[0009] The fourth technical problem to be solved by the present invention is to provide a method for controlling condensation on the baffle plate of the above-mentioned intelligent range hood.

[0010] The technical solution adopted by the present invention to solve the first technical problem mentioned above is: a smoke baffle anti-condensation device for an intelligent range hood, comprising a smoke baffle; characterized in that: the smoke baffle comprises a glass panel; The smoke baffle anti-condensation device also includes a heating film layer and a PVDF piezoelectric film layer disposed on the inner surface of the glass panel. The heating film layer is attached to the glass panel, and the PVDF piezoelectric film layer covers the side of the heating film layer away from the glass panel. The whole consisting of the heating film layer and the PVDF piezoelectric film layer is divided into n independent units.

[0011] The heating area of ​​the smoke baffle is divided into n independent units. Each unit has a heating film layer and a PVDF piezoelectric film layer. When the film vibrates, water droplets will change the vibration characteristics of the film (elastic change and viscosity change), thereby achieving a sub-second response to the initial micron-level water droplet condensation. It can accurately identify water droplets in different areas and can also heat different areas to assist in water removal, preventing dripping into the pot. It has lower power consumption and can realize intelligent detection of water droplet condensation and intelligent regional water removal to prevent dripping, thus improving the user's cooking experience.

[0012] Preferably, the cross-sectional area of ​​each independent unit on a section parallel to the inner surface of the glass panel is a×a cm², where the value of a ranges from 1 to 10.

[0013] The technical solution adopted by the present invention to solve the second technical problem mentioned above is: an intelligent range hood, including an air inlet and a fan, characterized in that: a smoke baffle and anti-condensation device as described above is applied to the range hood, the smoke baffle is used to open and close the smoke inlet on the air inlet, and when the smoke baffle is in the open state, the first glass panel is the lower surface of the smoke baffle or the inner surface facing the air inlet.

[0014] To facilitate automatic control, the range hood also includes a main controller, and the fan has a fan drive module. The fan drive module, the heating film layer of each independent unit, and the PVDF piezoelectric film layer of each independent unit are all electrically connected to the main controller.

[0015] The technical solution adopted by the present invention to solve the third technical problem mentioned above is: a method for identifying water droplets on the baffle plate of an intelligent range hood, using the range hood described above, characterized by including the following steps: 1) Signal generation and acquisition: 1.1) The main controller applies alternating current to the PVDF piezoelectric film layer of each unit and scans the frequency from low to high; 1.2) The main controller measures the voltage of the PVDF piezoelectric thin film layer. and current ; 1.3) Calculate the complex impedance spectrum: ; in, Where M is the mechanical loss resistance and M is the equivalent mass. It is an elastic flexibility; 2) Extract parameters from the acquired signals: Establish the equation: The solution is obtained by scanning at more than three frequency points and solving the system of equations. M The precise value; 3) Condensation criterion formula: When both conditions are met: It was determined to be water droplet condensation, of which: , This is the baseline value under dry conditions.

[0016] The first technical solution adopted by the present invention to solve the fourth technical problem mentioned above is: a method for controlling condensation in the smoke baffle of a range hood, characterized in that:

[0017] 1) Turn on the range hood;

[0018] 2) The main controller obtains the reference value of the elastic compliance. and the reference value of impedance ;

[0019] 3) Identification is performed using the water droplet identification method for the smoke baffle as described above;

[0020] 4) Calculate the overall coverage rate :

[0021] in, This represents the total area of ​​the units where water droplets condense. This represents the total area of ​​all units. Scene differentiation and decision-making are based on the rate of increase *s* of the number of independent units with water droplets and the coverage. , According to The current coverage rate is obtained through the calculation method. According to The calculation method used to obtain the previous coverage rate; if ,and (Return to step 3); if ,and If so, increase the fan speed of the range hood and proceed to step 5); if ,and If water droplets are detected, the individual units will be heated in designated areas, and the fan airflow will be increased, proceeding to step 5); where, and The preset coverage value. and The preset speed threshold; 5) Use the water droplet identification method of the smoke baffle as described above again to identify the current water droplet condensation state, verify the effect, and return to step 3).

[0022] Preferably, in step 5), the specific steps for effect verification are as follows: 5.1) Trigger local fast scan: Water droplet identification is performed only on independent units that have undergone heat treatment; 5.2) Determine the corresponding independent unit If the reduction is greater than 50%, mark the process as successful; otherwise, increase the heating voltage or time, and then return to step 5.1.

[0023] The second technical solution adopted by the present invention to solve the fourth technical problem mentioned above is: a method for controlling condensation in the smoke baffle of a range hood, characterized in that: 1) Start the range hood; 2) Identify whether the user is operating manually. If yes, enter manual operation mode. If no, determine whether smart mode is enabled. If yes, proceed to step 3). Otherwise, repeat this step. 3) Activate the default gear or the gear last selected by the user; 4) The main controller applies alternating current to the PVDF piezoelectric thin film layer of a single independent unit, and scans the frequency from low to high; 5) The independent unit is identified using the water droplet identification method for the smoke baffle as described above; 6) Cyclicly scan each PVDF piezoelectric thin film layer; 7) Calculate the overall coverage rate : in, This represents the total area of ​​the units where water droplets condense. This represents the total area of ​​all units. 8) Calculate the rate at which the number of independent cells with water droplets increases. : , According to The current coverage rate is obtained through the calculation method. According to The calculation method used to obtain the previous coverage rate; 9) And s is compared with the corresponding preset threshold: if If so, proceed to step 10); and Then proceed to step 11); if and Then wait for a certain period of time and return to step 2); where, and The preset coverage value. and The preset speed threshold; 10) Indicates the current cooking mode: Set the range hood fan to medium speed and check. If the condition is met, the independent unit with water droplets is continuously heated locally, and then proceed to step 12); if not, the independent unit with water droplets is intermittently heated, and then proceed to step 12). 11) Indicates that the current mode is frying / stir-frying: Set the range hood fan to high or keep it at high to intermittently heat the individual units with water droplets, and then proceed to step 12). 12) Check again whether the water droplets have been removed. If yes, turn off the heating and wait for a certain time before returning to step 4. If no, increase the heating voltage or time and wait for a certain time before returning to step 4.

[0024] Compared with the prior art, the advantages of this invention are as follows: the heating area of ​​the smoke baffle is divided into n independent units, each unit has a heating film layer and a PVDF piezoelectric film layer. When the film vibrates, water droplets will change the vibration characteristics of the film (elastic change and viscosity change), thereby realizing a sub-second response to the initial micron-level water droplet condensation, accurately identifying water droplets in the area, and also enabling regional heating to assist in water removal, preventing dripping into the pot. It has lower power consumption and can realize intelligent detection of water droplet condensation and intelligent regional water removal to prevent dripping, thus improving the user's cooking experience. Attached Figure Description

[0025] Figure 1This is a side view of the range hood installed according to an embodiment of the present invention (small air volume for steaming and cooking); Figure 2 This is a side view of the range hood installed according to an embodiment of the present invention (large air volume for steaming and cooking); Figure 3 This is a partial sectional side view (vertical section) of the smoke baffle of the range hood according to an embodiment of the present invention; Figure 4 This is a cross-sectional side view (horizontal section, without condensation) of the smoke baffle of the range hood according to an embodiment of the present invention; Figure 5 This is a cross-sectional side view (horizontal section, micro-condensation) of the smoke baffle of the range hood according to an embodiment of the present invention; Figure 6 This is a cross-sectional side view (horizontal section, showing obvious condensation) of the smoke baffle of the range hood according to an embodiment of the present invention; Figure 7 This is a control principle diagram of a range hood according to an embodiment of the present invention; Figure 8 This is a flowchart illustrating the signal generation and acquisition process of the PVDF piezoelectric thin film layer in the range hood according to an embodiment of the present invention; Figure 9 This is a flowchart illustrating the water droplet recognition and scene recognition process of a range hood according to an embodiment of the present invention. Figure 10 This is a control flowchart of the first embodiment of the range hood of the present invention; Figure 11 for Figure 10 The sub-flowchart for effect verification in the flowchart described above; Figure 12 This is a control flowchart of the second embodiment of the range hood of the present invention. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0027] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Since the embodiments disclosed in this invention can be arranged in different directions, these terms indicating direction are only for illustration and should not be regarded as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity. In addition, features defined with "first" and "second" may explicitly or implicitly include one or more of such features.

[0028] See Figure 1 and Figure 2 A range hood includes an air inlet 1 and a smoke baffle 2. The air inlet 1, as shown in this embodiment, has a smoke inlet (not shown, representing prior art) on its front side (the side facing the user during use). The smoke baffle 2 is movable relative to the air inlet 1, thus having a closed state and an open state. When the smoke baffle 2 is in the closed state, it covers the front side of the air inlet 1, closing the smoke inlet. When the smoke baffle 2 is in the open state, it opens to the front of the smoke inlet of the air inlet 1, forming a smoke-collecting space between the front of the smoke inlet and the smoke baffle 2. In this embodiment, the smoke baffle 2 is horizontal when in the open state, but the invention is not limited to this open state; it can also be tilted relative to the vertical direction, etc.

[0029] Noise generally increases significantly with increasing airflow, so a higher airflow does not necessarily mean a better experience. Many users choose low to medium settings in steaming / cooking mode to save energy (gas heating and range hood electricity) and reduce noise. However, this causes moisture to easily accumulate on the lower surface of the smoke baffle 2. (See [link / reference]). Figure 1 As indicated by the middle arrow, water droplets then fall into the pot. Moisture and other vapors are drawn towards the flue gas inlet by a greater lateral velocity, reducing the amount passing near the lower surface of the baffle plate 2. (See [reference]). Figure 2 As shown by the middle arrow, this can initially reduce the formation of water droplets on the lower surface of the baffle. However, when water condensation is severe, increasing the airflow cannot solve the problem of condensation dripping. It is necessary to use additional auxiliary heating of the glass surface to increase the evaporation rate of the water film and droplets, so as to prevent dripping into the pot and affecting the cooking experience and food safety.

[0030] For this reason, see Figure 3 and Figure 4In this invention, the smoke baffle 2 includes a glass panel 21 (which is the lower surface or the inner surface facing the air inlet 1 during operation). A heating film layer 22 and a PVDF piezoelectric film layer 23 are disposed on the inner surface of the glass panel 21. The heating film layer 22 can be tightly attached to the glass panel 21, and the PVDF piezoelectric film layer 23 covers the side of the heating film layer 22 away from the glass panel 21. Both can be the same size and shape. The overall area formed by the heating module 22 and the PVDF piezoelectric film layer 23 is divided into a×a cm² (the area on a cross section parallel to the inner surface of the glass panel 21, such as...). Figure 3 The horizontal plane shown is defined as n independent units, preferably a∈[1,10]cm, as shown. Figure 4 The diagram shows an independent heating control area of ​​a = 5 cm. This can be understood as a combination module consisting of n heating film layers 22 and PVDF piezoelectric film layers 23, which are independently (spaced out, without electrical connection) filled within the smoke baffle 2. Each PVDF piezoelectric film layer 23 is connected to a drive module (signal generator) that can output a sweep frequency signal such as 10kHz-1MHz (Vdrive = 5Vpp). Figure 4 The middle indicates that no water droplets have condensed. Figure 5 The middle part indicates the micro-condensation of water droplets. Figure 6 The middle part indicates that water droplets have clearly condensed. Figure 5 and Figure 6 The circles in the image represent water droplets.

[0031] See Figure 7 The range hood of this invention is an intelligent range hood, which may include a main controller 3 for intelligent detection and control. The main controller 3 has a processor, and the fan drive module 34 (fan not shown, can be in any existing form and installation location), each heating film layer 22, and each PVDF piezoelectric film layer 23 are all electrically connected to the main controller 3. Furthermore, the main controller 3 may also be electrically connected to a switch module 31, a storage module 32, and a lamp module 33, which are identical to those in the prior art. Additionally, the smoke baffle drive module 24 for driving the smoke baffle 2 is also electrically connected to the main controller 3.

[0032] The principle behind the water droplet detection using the aforementioned smoke baffle 2 is as follows: When the PVDF piezoelectric film layer 23 vibrates, the water droplets act like weights attached to the drum surface, altering the vibration characteristics—the more water, the slower the vibration (elastic change) and the faster the energy consumption (viscosity change). Based on this, a sub-second response to the initial micron-sized water droplet condensation is achieved, accurately identifying water droplets in specific areas. It also allows for zoned heating to assist in water removal, preventing dripping into the pot. With lower power consumption, it enables intelligent detection of water droplet condensation and intelligent zoned water removal to prevent dripping, enhancing the user's cooking experience. Detection sensitivity: Can identify water droplets with a diameter of 0.5mm or larger; Response time: From condensation to trigger action <0.8 seconds; Energy saving effect: Saves 40-60% more electricity than traditional constant temperature heating methods.

[0033] Based on this, for water droplet identification methods, please refer to... Figure 9 It includes the following steps:

[0034] 1) Signal generation and acquisition, see [link to documentation] Figure 8 :

[0035] 1.1) The drive module (signal generator) in the main controller 3 applies AC current to the PVDF piezoelectric film layer 23 of each unit, such as a voltage of 5V, and the frequency f is scanned from low to high (10kHz~1MHz);

[0036] 1.2) The main controller 3 measures the voltage of the PVDF piezoelectric thin film layer 23. and current , The amplitude and current can be obtained by conversion using the resistance method. Each contains a real part and an imaginary part; The angular frequency is ω = 2πf;

[0037] 1.3) Calculate the complex impedance spectrum: ;

[0038] Among them, the real part R m Mechanical loss resistance (reflecting surface viscous damping or energy loss) is related to the viscous resistance of water droplets; imaginary part. Includes equivalent mass M (related to the mass of the attached material) and elastic compliance. Information related to adhesion stiffness;

[0039] 2) Parameter extraction (frequency sweep and least squares fitting) of the acquired signals:

[0040] Establish the equation:

[0041]

[0042] The solution is obtained by scanning at three or more frequency points (e.g., 100kHz, 500kHz, 1MHz) and solving the system of equations. M The precise value is obtained through a method similar to reconstructing the shape of a three-dimensional object using photographs taken from multiple angles.

[0043] 3) Condensation criterion formula:

[0044] When both conditions are met: When water droplets are condensed, the specific parameters can be adjusted according to the height distance between the air inlet and the cookware of different machines. R m0 This is the baseline value under dry conditions (automatically calibrated upon startup or pre-calibrated in the laboratory). , ;

[0045] Water droplets condensing can also cause the surface to harden. Increased vibration energy loss (R) m Increase).

[0046] The condensation area can then be estimated:

[0047] Once a single water droplet is detected, the overall water droplet condensation state can be statistically analyzed, and the overall coverage rate can be calculated. :

[0048]

[0049] in, This represents the total area of ​​the units where water droplets condense (the number of units with water droplets multiplied by the area of ​​each unit). The total area of ​​all cells (total number of cells multiplied by cell area) is used to convert condensation into water droplet coverage (from 0 to 100%).

[0050] get Then, scene recognition and decision-making can be performed:

[0051] According to the rate s of increase of the humidity unit Coverage can distinguish between scenarios with large humidity differences, such as steaming / boiling and frying / stir-frying. This represents the current detected coverage. The coverage rate detected last time. The time difference between the two tests; see the table below:

[0052]

[0053] Table 1. Correspondence between cooking modes, water droplet coverage scenarios, and execution actions.

[0054] in the above table That is .

[0055] The specific water removal plan and workflow are as follows:

[0056] 1. Micro (initial) condensation treatment Triggering a transient pressurization for a period of time, such as 3 minutes, and suddenly increasing the wind speed (e.g., +50%) can generate fluid shear force to peel off micro water droplets. Specifically, the wind speed can be adjusted using the following control equation to ensure a smooth change in wind speed V (or flow rate Q and rotational speed N), so that people do not perceive sudden changes in noise:

[0057] in, Adjust the wind speed to the target. Given the current wind speed, the hyperbolic tangent tanh function can ensure a smooth change in wind speed.

[0058] 2. Treatment to prevent obvious water droplet condensation ( ): This involves zoned gradient heating, where target heating temperatures or heating power are defined in stages for the central and edge regions (higher temperatures are needed for evaporation in the central region, while heat diffusion is utilized at the edges). The following is a reference for defining target heating temperatures:

[0059] Central area temperature =

[0060] Edge zone temperature =

[0061] Then adjust the fan speed N according to the condensation area ratio k:

[0062]

[0063] The edge region includes at least the outermost ring of units, while the central region can be the middle unit, or it can include the middle unit and the outermost ring of units, or it can be the part within the outermost ring of units, which can be selected as needed.

[0064] In the above text, each unit is tested separately because: 1. Spatial resolution requirements: The smoke baffle 2 has a large area (usually >0.2㎡, such as 900mm long and 300mm wide), and testing the whole panel will cover up local condensation. Therefore, testing in areas with side lengths of 1~10cm can pinpoint the exact location; 2. Energy saving considerations: Heating only the actual condensation area saves more than 60% energy compared to overall heating. For example, if only 20% of the area is condensed, only the corresponding zone heating film layer 22 is activated.

[0065] See Figure 10 The anti-condensation water control method for the range hood of the present invention is calculated and controlled by the main controller 3, and includes the following steps:

[0066] 1) The range hood is turned on, performs a self-test, and initializes the system;

[0067] 2) The main controller 3 reads or calibrates the reference elastic flexibility from the storage module 32. and reference impedance ;

[0068] 3) Water droplet identification is performed using the method described above;

[0069] 4) Based on the coverage calculated after water droplet identification as described above, a pattern matching decision is made, as shown in Table 1: If there is no water, return to step 3); if there is slight condensation, then transiently increase the pressure and proceed to step 5); if there is obvious condensation, then zone heating is performed on the units where water droplets are detected, and the fan air volume is increased, and proceed to step 5).

[0070] 5) Identify the current water droplet condensation state, verify the effect, and then return to step 3). Before returning to step 3), parameters can be updated adaptively (such as fan speed and heating time when condensation is obvious).

[0071] See Figure 11 In step 5), the specific steps are as follows:

[0072] 5.1) Trigger local fast scan: Water droplet identification is performed only on independent units that have undergone heat treatment;

[0073] 5.2) Determine the corresponding independent unit If the decrease is greater than 50%, mark the process as successful. If not, upgrade the processing strategy, such as extending the heating time (e.g., 15 seconds) or increasing the pressure (e.g., by 20%), and then return to step 5.1.

[0074] See Figure 12 An alternative control method implementation includes the following steps:

[0075] 1) Start the range hood;

[0076] 2) Identify whether the user is operating manually. If yes, enter manual operation mode. If no, determine whether smart mode is enabled. If yes, proceed to step 3). Otherwise, repeat this step.

[0077] 3) Activate the default gear or the gear last selected by the user, and start intelligent detection;

[0078] 4) Apply AC current and perform frequency sweep detection on a single PVDF piezoelectric thin film layer 23 unit, in the same manner as the previous embodiment;

[0079] 5) Data analysis and processing: This unit involves the determination and marking of water droplet condensation.

[0080] 6) Cyclicly scan each PVDF piezoelectric thin film layer 23;

[0081] 7) Calculate the total condensate area or proportion, and estimate... ;

[0082] 8) Calculate the rate s of increase based on the number of independent units with water droplets;

[0083] 9) And s is compared with the corresponding preset threshold: if If so, proceed to step 10); and Then proceed to step 11); if and If no accumulation occurs, it means there is no accumulation and no processing is needed for now. It can be ignored and returned to step 2 after a certain period of time (Δt1).

[0084] 10) Indicates the current cooking mode: Set the range hood fan to medium speed and check. If the condition is met, the independent unit with water droplets is continuously heated locally, and then proceed to step 12); if not, the independent unit with water droplets is intermittently heated (pulse heating), and then proceed to step 12.

[0085] 11) Indicates that the current mode is frying / stir-frying: Set the range hood fan to high or keep it at high to intermittently heat the individual units with water droplets, and then proceed to step 12).

[0086] 12) Check again whether the water droplets have been removed. If yes, turn off the heating and wait for a certain time (Δt2) before returning to step 4. If no, increase the heating voltage or time and wait for a certain time (Δt2) before returning to step 4.

Claims

1. A smoke baffle anti-condensation device for an intelligent range hood, comprising a smoke baffle (2); characterized in that: The smoke baffle (2) includes a glass panel (21); The smoke baffle anti-condensation device also includes a heating film layer (22) and a PVDF piezoelectric film layer (23) disposed on the inner surface of the glass panel (21). The heating film layer (22) is attached to the glass panel (21), and the PVDF piezoelectric film layer (23) covers the side of the heating film layer (22) away from the glass panel (21). The whole consisting of the heating film layer (22) and the PVDF piezoelectric film layer (23) is divided into n independent units.

2. The anti-condensation device for the smoke baffle of the intelligent range hood according to claim 1, characterized in that: The cross-sectional area of ​​each independent unit on the section parallel to the inner surface of the glass panel (21) is a×a cm², where the value of a ranges from 1 to 10.

3. A smart range hood, comprising an air inlet (1) and a fan, characterized in that: The range hood is equipped with a smoke baffle anti-condensation device as described in claim 1 or 2. The smoke baffle (2) is used to open and close the smoke inlet on the air inlet body (1). When the smoke baffle (2) is in the open state, the glass panel (21) is the lower surface of the smoke baffle (2) or the inner surface facing the air inlet body (1).

4. The intelligent range hood according to claim 3, characterized in that: The range hood also includes a main controller (3), and the fan has a fan drive module (34). The fan drive module (34), the heating film layer (22) of each independent unit, and the PVDF piezoelectric film layer (23) of each independent unit are all electrically connected to the main controller (3).

5. A method for identifying water droplets on the baffle plate of an intelligent range hood, using the intelligent range hood according to claim 4, characterized in that: Includes the following steps: 1) Signal generation and acquisition: 1.1) The main controller (3) applies alternating current to the PVDF piezoelectric film layer (23) of each unit and scans the frequency from low to high; 1.2) The main controller (3) measures the voltage of the PVDF piezoelectric thin film layer (23). and current ; 1.3) Calculate the complex impedance spectrum: ; in, Where M is the mechanical loss resistance and M is the equivalent mass. It is an elastic flexibility; 2) Extract parameters from the acquired signals: Establish the equation: The solution is obtained by scanning at more than three frequency points and solving the system of equations. M The precise value; 3) Condensation criterion formula: When both conditions are met: It was determined to be water droplet condensation, of which: , This is the baseline value under dry conditions.

6. A method for controlling condensation in the baffle plate of an intelligent range hood, characterized in that: 1) Turn on the range hood; 2) The main controller (3) obtains the reference value of the elastic flexibility. and the reference value of impedance ; 3) Identification is performed using the water droplet identification method for the smoke baffle as described in claim 5; 4) Calculate the overall coverage rate : in, This represents the total area of ​​the units where water droplets condense. This represents the total area of ​​all units. Scene differentiation and decision-making are based on the rate of increase *s* of the number of independent units with water droplets and the coverage. , According to The current coverage rate is obtained through the calculation method. According to The calculation method used to obtain the previous coverage rate; if ,and (Return to step 3); if ,and If so, increase the fan speed of the range hood and proceed to step 5); if ,and If water droplets are detected, the individual units will be heated in designated areas, and the fan airflow will be increased, proceeding to step 5); where, and The preset coverage value. and The preset speed threshold; 5) Use the water droplet identification method of the smoke baffle as described in claim 5 again to identify the current water droplet condensation state, verify the effect, and return to step 3).

7. The method for controlling condensation prevention in the baffle plate of an intelligent range hood according to claim 6, characterized in that: In step 5), the specific steps for verifying the effect are as follows: 5.1) Trigger local fast scan: Water droplet identification is performed only on independent units that have undergone heat treatment; 5.2) Determine the corresponding independent unit If the reduction is greater than 50%, mark the process as successful; otherwise, increase the heating voltage or time, and then return to step 5.

1.

8. A method for controlling condensation in the smoke baffle of an intelligent range hood, characterized in that: 1) Start the range hood; 2) Identify whether the user is operating manually. If yes, enter manual operation mode. If no, determine whether smart mode is enabled. If yes, proceed to step 3). Otherwise, repeat this step. 3) Activate the default gear or the gear last selected by the user; 4) The main controller (3) applies alternating current to the PVDF piezoelectric thin film layer (23) of a single independent unit and scans the frequency from low to high; 5) The independent unit is identified using the water droplet identification method for the smoke baffle as described in claim 5; 6) Cyclicly scan each PVDF piezoelectric thin film layer (23); 7) Calculate the overall coverage rate : in, This represents the total area of ​​the units where water droplets condense. This represents the total area of ​​all units. 8) Calculate the rate at which the number of independent cells with water droplets increases. : , According to The current coverage rate is obtained through the calculation method. According to The calculation method used to obtain the previous coverage rate; 9) And s is compared with the corresponding preset threshold: if If so, proceed to step 10); and Then proceed to step 11); if and Then wait for a certain period of time and return to step 2); where, and The preset coverage value. and The preset speed threshold; 10) Indicates the current cooking mode: Set the range hood fan to medium speed and check. If the condition is met, the independent unit with water droplets is continuously heated locally, and then proceed to step 12); if not, the independent unit with water droplets is intermittently heated, and then proceed to step 12). 11) Indicates that the current mode is frying / stir-frying: Set the range hood fan to high or keep it at high to intermittently heat the individual units with water droplets, and then proceed to step 12). 12) Check again whether the water droplets have been removed. If yes, turn off the heating and wait for a certain time before returning to step 4. If no, increase the heating voltage or time and wait for a certain time before returning to step 4.

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