A method for self-adapting adjustment of air velocity of a range hood

Abstract

The present application relates to the technical field of range hood, and discloses a range hood wind speed self-adaptive adjusting method, a plurality of fan currents and a plurality of fan rotating speeds are one-to-one corresponding, in the working process, the range hood works under different fan currents; and the increasing trend of oil fume concentration is judged, and an oil fume concentration increasing threshold is set for the corresponding fan current, in the constant current working process of the fan, when the increasing value of the oil fume concentration relative to the reference oil fume concentration exceeds the oil fume concentration increasing threshold, the fan works under the next larger fan current for constant current. The range hood wind increasing of the present application can be divided into multiple stages, under each stage, the working mode of constant current and constant air volume within a certain range is realized, and the wind increasing model can be intelligently corrected along with the increasing trend of the oil fume concentration, the wind resistance sensitivity is effectively improved, and the smoke exhaust effect can be further improved when the exhaust pressure of the public flue is large and the smoke exhaust is not smooth or the flue pressure suddenly changes.

Description

Technical Field

[0001] This invention relates to the field of range hood technology, and in particular to a method for adaptive adjustment of fan speed in a range hood. Background Technology

[0002] A range hood is a kitchen appliance that purifies the environment by extracting and expelling smoke, fumes, and moisture generated during cooking, thus reducing kitchen pollution and purifying the air. Currently, the most advanced methods for adjusting range hood speed primarily involve using infrared sensors to detect the concentration of cooking fumes or combining this with other temperature sensors to adjust the fan speed and achieve different smoke extraction effects. However, while current fume or temperature sensors can achieve some degree of self-adjustment of the range hood's fan speed, in practice, due to variations in cooking ingredients, cooking methods, the measured physical quantities, and even the cooking environment, it's impossible to accurately match the airflow volume with the actual concentration of cooking fumes. This results in a poor user experience, only roughly achieving this single function, and is also relatively expensive.

[0003] Furthermore, since cooking is currently concentrated at noon or in the evening, situations frequently arise where high pressure in the shared exhaust duct leads to poor smoke extraction and even backflow of fumes. Currently, the most advanced methods for resisting pressure and preventing backflow involve using constant current control for the DC fan, achieving constant smoke extraction through automatic multi-speed settings. However, issues such as insufficient or ineffective airflow due to high pressure in the shared exhaust duct or sudden pressure changes can persist. Additionally, while users typically need to manually turn off the range hood after cooking, and relatively intelligent models usually automatically shut off after a one-minute delay, the fixed cleaning time after each cooking session can lead to insufficient cleaning and lingering fumes, or forgetting to turn off the range hood results in excessively long cleaning times and high-power fan operation, consuming excessive energy. Sometimes, the range hood needs to be linked to the cooktop or manually activated during cooking for smoke extraction. Summary of the Invention

[0004] The purpose of this invention is to provide a method for adaptively adjusting the fan speed of a range hood according to the changing trend of oil fume concentration, thereby providing at least a beneficial option or creating conditions to solve one or more technical problems existing in the prior art.

[0005] To achieve the above objectives, the present invention adopts the following technical solution.

[0006] An adaptive control method for the fan speed of a range hood mainly includes the following steps.

[0007] 1) Match several fan currents with several fan speeds one by one. During operation, the range hood operates under constant current at different fan currents.

[0008] 2) Determine the fan speed increase. There is a speed increase threshold corresponding to the fan current. During the constant current operation of the fan, when the increase in fan speed relative to the reference speed exceeds the corresponding speed increase threshold, control the fan to operate at a higher fan current in the next stage for constant current operation.

[0009] 3) To determine the increasing trend of oil fume concentration, a threshold for the increase of oil fume concentration is set for the corresponding fan current. During the constant current operation of the fan, when the increase of oil fume concentration relative to the reference oil fume concentration exceeds the threshold for the increase of oil fume concentration, the fan is controlled to operate at a larger current in the next stage.

[0010] 4) Alternately perform the judgments in steps 2) and 3). When the fan speed exceeds the maximum protection speed or the fan current reaches the maximum protection current, issue a fault alarm for severe duct blockage.

[0011] More preferably, the different fan currents are obtained by setting different multiples on the same base value.

[0012] More preferably, the current of the next stage fan is set as a multiple of the current of the previous stage fan.

[0013] More preferably, the current of each fan is a value obtained through experiments or empirical values.

[0014] More preferably, the reference speed is a fixed constant, which is a value measured experimentally or an empirical value.

[0015] More preferably, the fan speed corresponding to the current fan current is used as the reference speed.

[0016] More preferably, the baseline oil fume concentration is a fixed constant, which is a value measured experimentally or an empirical value.

[0017] More preferably, the oil fume concentration during the operation of the previous stage fan current is used as the benchmark oil fume concentration.

[0018] More preferably, the adaptive control method for range hood wind speed further includes post-cleaning adaptive control, which mainly includes the following steps.

[0019] 1) Set several oil fume concentration ranges and several cleaning times after the range hood, with each oil fume concentration range and cleaning time after the range hood corresponding to the other.

[0020] 2) Set the range of oil fume concentration after cleaning is completed.

[0021] 3) When cleaning after starting, determine the maximum value Q of oil fume within a continuous time period. 烟maxThe range hood is controlled to perform post-cleaning based on the range hood's post-cleaning time corresponding to the range hood's concentration range.

[0022] 4) After cleaning is completed, measure the oil fume value Q. 烟 If Q 烟 If the concentration of oil fumes exceeds the upper limit of the range, perform a follow-up cleaning for N times the duration, where N > 1; if Q 烟 If the concentration falls within the range of oil fume concentration, perform a post-cleaning cycle of M times the duration, where 0 < M ≤ 1; if Q 烟 If the concentration of oil fumes is less than the lower limit of the range, the subsequent cleaning procedure will end.

[0023] More preferably, the continuous time period should be selected within 3-30 seconds.

[0024] The technical solution provided by this invention has at least the following technical effects or advantages.

[0025] 1. Under the maximum speed protection range or maximum protection current, the range hood's air supply can be divided into multiple stages. In each stage, a constant current and constant air volume working mode is achieved within a certain range. Furthermore, the air supply model can be intelligently corrected as the concentration of oil fumes increases, effectively improving the sensitivity to wind resistance. When the pressure in the common exhaust duct is high and the exhaust is not smooth, or when the duct pressure changes suddenly, the highly sensitive DC air supply scheme can further improve its smoke extraction effect.

[0026] 2. After cleaning is completed, measure the oil fume level Q. 烟 And according to Q 烟 The adaptive cleaning time can be adjusted automatically according to cooking needs. For example, the more oil fumes during cooking, the longer the corresponding cleaning time will be. This achieves the best kitchen air quality after cooking while significantly reducing the energy consumption of the range hood fan during high-power operation. Attached Figure Description

[0027] Figure 1 The diagram shows the adaptive adjustment process of a range hood under normal operating conditions.

[0028] Figure 2 The figure shown is a comparison between the wind speed regulation method of the present invention and the existing constant current driven method.

[0029] Figure 3 The diagram shows the adaptive adjustment process of the range hood during the back cleaning operation. Detailed Implementation

[0030] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings, making the technical solution and beneficial effects of the present invention clearer and more explicit. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0031] Additional aspects and advantages of the invention will become apparent in the following description or may be learned by practice of the invention.

[0032] An adaptive control method for range hood fan speed comprises the following basic steps: 1) Assigning a specific pair of fan currents to a specific fan speed. During operation, the range hood operates under constant current conditions at different fan currents. 2) Determining the fan speed increase. A speed increase threshold is set for each fan current. During constant current operation, if the increase in fan speed relative to the reference speed exceeds the corresponding speed increase threshold, the fan is controlled to operate under a higher current than the next lower fan level. 3) Determining the increasing trend of oil fume concentration. A oil fume concentration increase threshold is set for each fan current. During constant current operation, if the increase in oil fume concentration relative to the reference oil fume concentration exceeds the oil fume concentration increase threshold, the fan is controlled to operate under a higher current than the next lower fan level. 4) Alternating between steps 2) and 3). When the fan speed exceeds the maximum protection speed or the fan current reaches the maximum protection current, a fault alarm indicating severe duct blockage is issued.

[0033] Reference Figure 1As shown, an adaptive control method for the range hood's fan speed in one embodiment is as follows: 1) According to the cooking mode, the fan operates with constant current and cross-flow speed at the corresponding current and speed; the current of the fan is defined as I, and the corresponding speed is n; 2) In the first stage of increasing airflow, as the load becomes lighter, the fan speed will increase. When the change in fan speed is greater than n*10%, the fan current is increased to I1, I1=1.2*I, and the corresponding speed is n1. The trend of increasing oil fume concentration is further judged, and the oil fume concentration is compared with the concentration when the fan current is I. When the oil fume concentration increases by more than 15%, the fan current is increased to I1′, I1′=1.5*I, and the corresponding speed is n1′. 3) In the second stage of increasing airflow, as the wind resistance increases, the load will continue to become lighter. Similarly, as the load becomes lighter, the fan speed will increase. When the change in fan speed is greater than n1′*6%, the fan current is increased to I2, I2=1.8*I, and the corresponding speed is n2. Continue to assess the increasing trend of oil fume concentration by comparing it with the concentration when the fan current is I1′. When the oil fume concentration increases by more than 15%, the fan current increases to I2′, where I2′ = 2.0 * I. The corresponding rotational speed at this point is n2′. 3) Continue to assess the changes in fan speed and the increasing trend of oil fume concentration. When the change in fan speed is greater than n2′ * 5%, determine whether it exceeds the maximum protection speed ni or the maximum current Ii. If so, issue a fault message indicating severe duct blockage. If not, the fan operates at constant current and crosswind speed according to the cooking mode and corresponding current and speed.

[0034] Reference Figure 2 As shown, compared with the existing constant current drive method, the adaptive fan speed control method of the range hood provided in this embodiment, when the pressure of the common flue increases, on the basis of the existing constant current constant suction, and combined with the trend of oil fume, further selects whether to double the current to further increase the fan speed based on the trend of increasing oil fume concentration during exhaust, to achieve adaptive smoke extraction model correction, providing reasonable energy efficiency allocation for different cooking scenarios; cruise sensing of exhaust pressure, changing according to smoke, adjusting air volume and air pressure according to smoke volume; achieving rapid pressure boosting and exhaust during peak hours and stir-frying, and energy-saving and stable suction during off-peak hours and stewing, intelligent smoke extraction, making cooking less hectic, and comprehensively improving the intelligent smoke extraction effect. Figure 2 In the diagram, curve A represents the wind pressure and speed variation curve of this embodiment, while curve B represents the wind pressure and speed variation curve of the traditional constant current and constant suction method.

[0035] It should be noted that the current of different fans can be set by multiplying the same base value, or by multiplying the current of the previous stage fan. Depending on the actual needs, the current of each fan can also be a value obtained through experiments or empirical values.

[0036] In some embodiments, the reference oil fume concentration can be a fixed constant, in addition to being the oil fume concentration based on the current of the previous stage fan. Relatively speaking, using the oil fume concentration based on the current of the previous stage fan as the reference oil fume concentration to determine the increasing trend of oil fume concentration has higher accuracy.

[0037] In some embodiments, the reference speed can be either the fan speed corresponding to the current fan current or a fixed constant. Relatively speaking, using the fan speed corresponding to the current fan current as the reference speed to determine the fan speed increase has higher accuracy.

[0038] Reference Figure 3 As shown, in one embodiment, the adaptive control method for range hood fan speed also includes adaptive post-cleaning control, which can automatically adjust the post-cleaning time of the range hood according to cooking needs. For example, the greater the oil fumes during cooking, the longer the corresponding post-cleaning time. At the same time, it has real-time monitoring of oil fume quality, realizing intelligent range hood operation, and can further adjust the post-cleaning time of the range hood to achieve the best kitchen air quality after cooking while fully reducing the energy consumption of the range hood fan operating at high power.

[0039] When cooking, if the range hood is not manually turned on, the range hood sensor detects the oil fume level Q. 烟 ≥Q 标 When the range hood automatically turns on, Q will be activated. 标 The ambient oil fume level that the range hood needs to operate at is the specified value. This value can be an empirical value or an experimental value.

[0040] The specific adaptive control process for post-cleaning is as follows: 1) Set several oil fume concentration ranges and several post-cleaning durations for the range hood, with each oil fume concentration range and post-cleaning duration corresponding to a specific one; 2) When post-cleaning is started, determine the maximum oil fume value Q within a continuous time period. 烟max The range hood is controlled to perform post-cleaning based on the range hood's post-cleaning time corresponding to the range hood's concentration range; 3) When post-cleaning is completed, the oil fume value Q is detected. 烟 If Q 烟 ≥1.5Q 标 If so, continue with a cleanup process that lasts twice as long. If 1.5Q 标 >Q 烟 ≥Q 标 If Q continues for the same duration, then another cleaning session will be performed. 烟 <Q 标 Then the cleaning process ends.

[0041] In this embodiment, the oil fume value is obtained by an oil fume sensor. The preferred continuous time period is 10 seconds, i.e., the maximum oil fume value Q is determined within 10 seconds. 烟maxThe system determines the range of oil fume concentration and then updates the corresponding post-cleaning time. Obviously, those skilled in the art can appropriately change the duration of the continuous time period according to different actual needs, such as selecting a range of 3-30 seconds; this is not limited to this embodiment.

[0042] It should be noted that in some embodiments, other ranges of oil fume concentration can be used instead of 1.5Q. 标 -Q 标 The oil fume value Q after cleaning is completed 烟 If the oil fume concentration exceeds the upper limit of the range, perform a follow-up cleaning for N times the duration, where N > 1; the oil fume value Q at the end of the follow-up cleaning is... 烟 If the fume concentration falls within the range specified by the oil fume concentration, perform a post-cleaning operation for a duration of M times, where 0 < M ≤ 1; the oil fume value Q at the end of the post-cleaning operation... 烟 If the concentration of oil fumes is less than the lower limit of the range, the subsequent cleaning procedure will end.

[0043] It should also be noted that, in the description of this invention, any process or method described in the flowcharts or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process, and the scope of the preferred embodiments of the invention includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order according to the functions involved, as should be understood by those skilled in the art to which the embodiments of the invention pertain.

[0044] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-including system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and programmable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0045] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0046] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0047] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0048] For directional terms, such as "center," "lateral," "longitudinal," "length," "width," "thickness," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," these indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present 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. They should not be construed as limiting the specific protection scope of the present invention.

[0049] In this invention, unless otherwise explicitly specified and limited, the terms "assembly," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can also refer to a mechanical connection; they can refer to a direct connection or a connection through an intermediate medium; or they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0050] In this invention, unless otherwise specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "below," and "over" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Above," "below," and "below" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0051] Based on the above description of the structure and principles, those skilled in the art should understand that this invention is not limited to the specific embodiments described above. Improvements and substitutions made using techniques known in the art based on this invention all fall within the scope of protection of this invention, which should be defined by the claims and their equivalents. Parts not described in the specific embodiments are all prior art or common knowledge.

Claims

1. A method for adaptive control of fan speed in a range hood, characterized in that, The main steps include: 1) Match several fan currents with several fan speeds one by one. During operation, the range hood operates under constant current at different fan currents. 2) Determine the fan speed increase. There is a speed increase threshold corresponding to the fan current. During the constant current operation of the fan, when the increase in fan speed relative to the reference speed exceeds the corresponding speed increase threshold, control the fan to operate at a higher current in the next stage for constant current operation. 3) To determine the increasing trend of oil fume concentration, a threshold for the increase of oil fume concentration is set for the corresponding fan current. During the constant current operation of the fan, when the increase of oil fume concentration relative to the reference oil fume concentration exceeds the threshold for the increase of oil fume concentration, the fan is controlled to operate at a constant current with a larger current at the next stage. 4) Alternately perform the judgments in steps 2) and 3). When the fan speed exceeds the maximum protection speed or the fan current reaches the maximum protection current, issue a fault alarm for severe duct blockage. It also includes post-cleaning adaptive control, which mainly includes the following steps: 1) Set several oil fume concentration ranges and several cleaning times after the range hood, with each oil fume concentration range and the cleaning time after the range hood corresponding to the other. 2) Set the range of oil fume concentration after cleaning is completed; 3) When cleaning after starting, determine the maximum value Q of oil fume within a continuous time period. 烟max The range of oil fume concentration is determined, and the cleaning time of the range hood corresponding to that oil fume concentration range is used to control the range hood to perform post-cleaning. 4) After cleaning is completed, measure the oil fume value Q. 烟 If Q 烟 If the concentration of oil fumes exceeds the upper limit of the range, perform a follow-up cleaning for N times the duration, where N > 1; if Q 烟 If the concentration falls within the range of oil fume concentration, perform a post-cleaning cycle of M times the duration, where 0 < M ≤ 1; if Q 烟 If the concentration of oil fumes is less than the lower limit of the range, the subsequent cleaning procedure will end.

2. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, Different fan currents are obtained by setting different multiples on the same base value.

3. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The current of the next stage fan is obtained by multiplying the current of the previous stage fan.

4. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The current of each fan is a value obtained through experiments or empirical values.

5. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The reference speed is a fixed constant, which is a value obtained experimentally or empirically.

6. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The fan speed corresponding to the current fan current is used as the reference speed.

7. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The baseline oil fume concentration is a fixed constant, which is a value measured experimentally or an empirical value.

8. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, The oil fume concentration during the operation of the first-stage fan current is used as the benchmark oil fume concentration.

9. The adaptive fan speed control method for a range hood according to claim 1, characterized in that, Select a continuous time period between 3 and 30 seconds.

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