A range hood and a control method thereof

Abstract

The present application relates to a kind of range hood and its control method, wherein the range hood includes: casing, with oil fume passage;It is characterized by further comprising: emitting module, be located in oil fume passage, the emitting module can emit the light of first wavelength and second wavelength, the absorption capacity of water vapor to the light of first wavelength is lower than the absorption capacity of water vapor to the light of second wavelength, and / or the scattering ability of water vapor to the light of first wavelength is lower than the scattering ability of water vapor to the light of second wavelength;Receiving module, be located in oil fume passage and with the emitting module opposite arrangement, the receiving module receives the light signal emitted by the emitting module;Controller is connected with receiving module, the controller is configured to: can be analyzed to the light signal received by receiving module, obtains the water vapor and oil fume condition in oil fume passage.This range hood can realize the differentiation of water vapor and oil fume in oil fume passage, to realize the identification of different cooking scene.

Description

Technical Field

[0001] This invention relates to the field of oil fume purification technology, and in particular to an oil fume extractor and its control method. Background Technology

[0002] As an essential kitchen appliance in every household, the range hood works by using a high-speed rotating impeller in the casing to draw in cooking fumes from the air inlet, filter the fumes using the impeller, and then expel the filtered fumes from the air outlet, thus purifying the kitchen air.

[0003] Traditional range hoods operate with fixed speeds or settings, requiring users to manually select the appropriate setting based on different scenarios such as stir-frying or steaming. However, users typically engage in various cooking activities that affect the amount of smoke generated in the cooking area, such as stir-frying, adding ingredients, or lifting the lid to create a sudden surge of smoke or steam. Traditional range hoods with fixed speeds or settings struggle to adapt to these unexpected situations.

[0004] To address this technical problem, Chinese invention patent ZL201911272109.X (authorization announcement number CN110848781B) discloses a range hood, including: a fan, a fan drive assembly for driving the fan, a smoke collection chamber disposed on the smoke inlet, a particulate matter sensor for collecting particulate matter concentration in the fumes at preset time intervals, and a controller; the controller is used to receive the particulate matter concentration collected by the particulate matter sensor at preset time intervals. Although this range hood can select the corresponding cooking mode based on the particulate matter concentration, it has the following limitations: because the above-mentioned range hood detects the particulate matter concentration in the fumes, this detection method cannot distinguish between water vapor and oil fumes, resulting in inaccurate judgment of the cooking scenario. Therefore, further improvements to the existing technology are needed. Summary of the Invention

[0005] The first technical problem to be solved by the present invention is to provide a range hood that can distinguish between water vapor and oil fumes in the fume duct, in contrast to the above-mentioned prior art.

[0006] The second technical problem to be solved by the present invention is to provide a control method for the above-mentioned range hood, which can realize automatic control of different cooking scenarios and dynamically adjust the fan speed of the range hood.

[0007] The technical solution adopted by the present invention to solve the first technical problem mentioned above is: a range hood, comprising:

[0008] The casing has an oil fume duct;

[0009] Its features also include:

[0010] The emitting module is located in the fume duct. The emitting module can emit light of a first wavelength and a second wavelength. The absorption capacity of water vapor for the first wavelength light is lower than that of water vapor for the second wavelength light, and / or the scattering capacity of water vapor for the first wavelength light is lower than that of water vapor for the second wavelength light.

[0011] A receiving module is located inside the fume duct and is positioned opposite to the transmitting module. The receiving module receives the light signal emitted by the transmitting module.

[0012] A controller, connected to a receiving module, is configured to analyze the light signals received by the receiving module to obtain information on water vapor and oil fumes in the fume channel.

[0013] To reduce interference between the first and second wavelengths of light and improve comparability, the transmitting module emits the first and second wavelengths of light in an alternating manner of odd and even periods, with the odd and even periods being the same.

[0014] The transmitting module includes two transmitting units: a first transmitting unit that transmits light of a first wavelength and a second transmitting unit that transmits light of a second wavelength.

[0015] To reduce costs, the first transmitting unit and the second transmitting unit share the same receiving module.

[0016] Preferably, the first wavelength and the second wavelength are substantially similar.

[0017] The technical solution adopted by the present invention to solve the second technical problem mentioned above is: a control method for a range hood as described above, wherein a fan is provided inside the casing, characterized by comprising the following steps:

[0018] Step 1: Acquire the optical signals received by the receiving module during the odd and even periods respectively, and denote the optical signal received by the receiving module during the odd period as I. 奇 The optical signal received by the receiving module during an even period is denoted as I. 偶 ;

[0019] Step 2, determine I 奇 Or I 偶 Is it less than the set threshold I? a If yes, proceed to step 3; otherwise, proceed to step 4.

[0020] Step 3, Determine |I 奇 -I 偶|If the difference is greater than the preset difference △I, it is determined that the current oil fume channel is mainly filled with water vapor. The fan in the casing is switched to a low level or kept at a low level, and the process proceeds to step 5. If not, it is determined that the current oil fume channel is mainly filled with oil fumes. The fan in the casing is switched to a high level or kept at a high level, and the process proceeds to step 5.

[0021] Step 4: Determine that the current fume duct is mainly filled with air, turn off the fan inside the casing, and proceed to Step 5;

[0022] Step 5: After waiting for the set time, proceed to Step 1 again.

[0023] Preferably, the light signals received by the receiving module in step 1 during odd and even periods are light flux.

[0024] To improve the accuracy of the determination, step 4, when determining that the current fume duct is mainly composed of air, also includes the following determination:

[0025] The controller determines whether the stove is turned on. If it is, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly filled with air.

[0026] Alternatively, it can determine if there is a heat source below the range hood. If so, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly composed of air.

[0027] Furthermore, in step 3, when it is determined that the current fume duct is mainly filled with water vapor, the controller determines that the current stove is in a steaming or boiling cooking scenario.

[0028] Furthermore, in step 3, when it is determined that the current fume duct is mainly filled with oil fumes, the controller determines that the current stove is in a stir-fry cooking scenario.

[0029] Compared with the prior art, the advantages of the present invention are as follows: by setting a transmitting module that emits two wavelengths of light and a receiving module that receives light signals in the fume duct, the water vapor and oil fumes in the fume duct can be distinguished due to the different absorption or scattering abilities of water vapor, oil fumes and air. In addition, air can also be distinguished, thereby enabling the identification of different cooking scenarios and changing the fan speed according to different cooking scenarios, thus improving the user experience. Attached Figure Description

[0030] Figure 1 This is a schematic diagram illustrating the use of the range hood in an embodiment of the present invention;

[0031] Figure 2 for Figure 1 Installation diagram of the transmitting and receiving modules;

[0032] Figure 3 This is a flowchart of the range hood control method in an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the light signal emitted by the transmitting module in an embodiment of the present invention;

[0034] Figure 5 This is a schematic diagram of the light signal received by the receiving module in a scenario where cooking has not yet begun or cooking has ended, as described in an embodiment of the present invention.

[0035] Figure 6 This is a schematic diagram of the light signal received by the receiving module during a stir-fry cooking scenario in an embodiment of the present invention;

[0036] Figure 7 This is a schematic diagram of the light signal received by the receiving module during a steaming or boiling cooking scenario in an embodiment of the present invention. Detailed Implementation

[0037] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0038] like Figure 1 As shown, the range hood in this embodiment includes a housing 1 and a fan. The housing 1 has a fume duct 10, and the fan is located within the fume duct 10. This fan uses existing technology and will not be described in detail here. A cooktop a is located below the range hood.

[0039] The range hood in this embodiment also includes a transmitting module, a receiving module 3, and a controller. Both the transmitting module and the receiving module 3 are located within the fume duct 10, with the receiving module 3 positioned opposite to the transmitting module. Figure 2 As shown, in this embodiment, the receiving module 3 and the transmitting module are respectively located on the left and right side walls of the housing 1. The transmitting module can emit light of a first wavelength and a second wavelength. The absorption capacity of water vapor for the first wavelength light is lower than that for the second wavelength light, and / or the scattering capacity of water vapor for the first wavelength light is lower than that for the second wavelength light. The receiving module 3 receives the light signal emitted by the transmitting module. The controller is connected to the receiving module 3 and is configured to analyze the light signal received by the receiving module 3 to obtain the water vapor and oil fume conditions in the fume channel 10. The controller in this embodiment can directly adopt the controller configured in existing range hoods.

[0040] The transmitting module includes two transmitting units: a first transmitting unit 21 that emits light of a first wavelength and a second transmitting unit 22 that emits light of a second wavelength. To reduce costs, the first transmitting unit 21 and the second transmitting unit 22 share the same receiving module 3. In this embodiment, both transmitting units can be infrared emitting tubes, and the receiving module can be an infrared receiving tube. The working principles of the transmitting unit and the receiving module are existing technologies and will not be elaborated here.

[0041] The transmitting module emits light of the first wavelength and the second wavelength in an alternating pattern of odd and even periods, with the odd and even periods being the same. In this embodiment, the first wavelength and the second wavelength are basically close, wherein the first wavelength is the sensitive wavelength of water vapor (the band in which water vapor has significant absorption characteristics in the infrared spectrum of this wavelength, such as 2.59um or 2.6um), and the second wavelength is the non-sensitive wavelength of water vapor (such as 2.50um, or similar values, such as 2.45um), but the second wavelength has a certain absorption and scattering ability for oil fumes.

[0042] like Figure 3 As shown, this embodiment also involves the control method of the above-mentioned range hood, which includes the following steps:

[0043] Step 1: Acquire the optical signals received by the receiving module during the odd and even periods respectively, and denote the optical signal received by the receiving module during the odd period as I. 奇 The optical signal received by the receiving module during an even period is denoted as I. 偶 ;

[0044] In this embodiment, the light signals received by the receiving module during odd and even periods are light flux.

[0045] In this embodiment, before step 1, it also includes controlling whether the range hood is turned on in manual operation or smart mode. If smart mode is turned on, then the smart monitoring mode is activated and the process proceeds to step 1.

[0046] Step 2, determine I 奇 Or I 偶 Is it less than the set threshold I? a If yes, proceed to step 3; otherwise, proceed to step 4.

[0047] The set threshold I in this embodiment a This was confirmed through experiments or experience.

[0048] Step 3, Determine |I 奇 -I 偶|If the difference is greater than the preset difference △I, it is determined that the current oil fume channel is mainly filled with water vapor. The fan in the casing is switched to a low level or kept at a low level, and the process proceeds to step 5. If not, it is determined that the current oil fume channel is mainly filled with oil fumes. The fan in the casing is switched to a high level or kept at a high level, and the process proceeds to step 5.

[0049] In this embodiment, the fan has at least two speed settings, and the higher the speed setting, the higher the fan speed. The low and high speed settings mentioned above are relative to the current speed setting of the fan.

[0050] When the current fume duct is determined to be mainly filled with water vapor, the controller determines that the current stove is in a steaming or boiling cooking scenario; when the current fume duct is determined to be mainly filled with oil fumes, the controller determines that the current stove is in a stir-fry cooking scenario; the preset difference ΔI in this embodiment is obtained through experiments or experience.

[0051] Step 4: Determine that the current fume duct is mainly filled with air, turn off the fan inside the casing, and proceed to Step 5;

[0052] Step 5: After waiting for the set time, proceed to Step 1 again.

[0053] In addition, step 4, when determining that the current fume duct is mainly composed of air, also includes the following judgment:

[0054] The controller determines whether the stove is turned on. If it is, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly filled with air. Alternatively, the controller determines whether there is a heat source below the range hood. If it is, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly filled with air.

[0055] To verify the effectiveness of the method in this invention, experiments were conducted in the following three scenarios in this embodiment, as detailed below:

[0056] Scenario 1: No cooking or cooking completed;

[0057] Scenario 2: Stir-fry cooking scenario;

[0058] Scenario 3: Steaming and boiling cooking scenarios;

[0059] The light signals emitted by the transmitting module in scenarios one, two, and three are all as described above. Figure 4 As shown, where Figure 4The first time period (t0~t1) corresponds to the first cycle, the second time period (t1~t2) corresponds to the second cycle, ... the sixth time period (t5~t6) corresponds to the sixth cycle. The first, third and fifth cycles correspond to odd cycles, and the second, fourth and sixth cycles correspond to even cycles. The odd cycle corresponds to the first transmitting unit emitting light of the first wavelength, and the even cycle corresponds to the second transmitting unit emitting light of the second wavelength.

[0060] The light signal received by the receiving module in the following scenario is as follows: Figure 5 As shown, the light signal received by the receiving module in scenario two is as follows: Figure 6 As shown, the light signal received by the receiving module in scenario three is as follows: Figure 7 As shown; I2 > I3. In scenario one, the proportion of oil fumes and water vapor in the fume duct is very small, and the inhaled airflow is mainly air, so the air has little impact on the light. In scenario two, the proportion of oil fumes in the fume duct is very large, and the light is affected by the absorption or scattering of oil fumes, thus causing... Figure 6 The optical flux of the receiving module is greater than Figure 5 The light flux of the receiving module is affected by water vapor absorption or scattering in scenario three, resulting in a decrease in the light flux of the receiving module. However, since water vapor has different absorption or scattering capabilities for different wavelengths of light, the light flux of the receiving module is different in odd and even periods.

Claims

1. A range hood, comprising: The casing (1) has an oil fume duct (10); Its features also include: The emitting modules (21, 22) are located in the fume duct (10). The emitting modules (21, 22) can emit light of a first wavelength and a second wavelength. The absorption capacity of water vapor for the first wavelength light is lower than that of water vapor for the second wavelength light, and / or the scattering capacity of water vapor for the first wavelength light is lower than that of water vapor for the second wavelength light. The receiving module (3) is located in the fume duct (10) and is positioned opposite to the transmitting module (21, 22). The receiving module (3) receives the light signal emitted by the transmitting module (21, 22). The controller is connected to the receiving module (3) and is configured to analyze the light signal received by the receiving module (3) to obtain the water vapor and oil fume conditions in the fume channel (10).

2. The range hood according to claim 1, characterized in that: The transmitting modules (21, 22) emit light of the first wavelength and the second wavelength in an alternating manner of odd and even periods, and the odd and even periods are the same.

3. The range hood according to claim 2, characterized in that: The transmitting module (21, 22) includes two transmitting units, namely a first transmitting unit (21) that transmits light of a first wavelength and a second transmitting unit (22) that transmits light of a second wavelength.

4. The range hood according to claim 3, characterized in that: The first transmitting unit (21) and the second transmitting unit (22) share the same receiving module (3).

5. The range hood according to any one of claims 2 to 4, characterized in that: The first wavelength and the second wavelength are basically the same.

6. A control method for a range hood as described in any one of claims 2 to 5, wherein a fan is provided inside the casing, characterized in that... Includes the following steps: Step 1: Acquire the optical signals received by the receiving module during the odd and even periods respectively, and denote the optical signal received by the receiving module during the odd period as I. 奇 The optical signal received by the receiving module during an even period is denoted as I. 偶 ; Step 2, determine I 奇 Or I 偶 Is it less than the set threshold I? a If yes, proceed to step 3; otherwise, proceed to step 4. Step 3, Determine |I 奇 -I 偶 |If the difference is greater than the preset difference △I, it is determined that the current oil fume channel is mainly filled with water vapor. The fan in the casing is switched to a low level or kept at a low level, and the process proceeds to step 5. If not, it is determined that the current oil fume channel is mainly filled with oil fumes. The fan in the casing is switched to a high level or kept at a high level, and the process proceeds to step 5. Step 4: Determine that the current fume duct is mainly filled with air, turn off the fan inside the casing, and proceed to Step 5; Step 5: After waiting for the set time, proceed to Step 1 again.

7. The control method according to claim 6, characterized in that: In step 1, the light signals received by the receiving module during odd and even periods are light flux.

8. The control method according to claim 6, characterized in that: Step 4, when determining that the current fume duct is mainly composed of air, also includes the following judgment: The controller determines whether the stove is turned on. If it is, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly filled with air. Alternatively, it can determine if there is a heat source below the range hood. If so, the controller determines that the current receiving module is malfunctioning; otherwise, it determines that the current fume duct is mainly composed of air.

9. The control method according to any one of claims 6 to 8, characterized in that: In step 3, when it is determined that the current fume duct is mainly filled with water vapor, the controller determines that the current stove is in a steaming or boiling cooking scenario.

10. The control method according to any one of claims 6 to 8, characterized in that: In step 3, when it is determined that the current fume duct is mainly filled with oil fumes, the controller determines that the current stove is in a stir-fry cooking scenario.

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