A system and method for preventing kitchen fume cross-space escape ventilation

Abstract

This invention relates to the field of residential ventilation and air purification technology, specifically to a ventilation system and control method for preventing kitchen fumes from escaping across spaces. The system includes a main exhaust system for a range hood and a double-layered air curtain above the kitchen doorway. The double-layered airflow forms a stable isolation barrier, preventing fumes from spreading into the living room. The air curtain employs a purely mechanical thermodynamic response structure, utilizing the thermal deformation of a bimetallic strip to drive the displacement of internal partition plates, adaptively adjusting the airflow volume and outlet angle of the two airflow paths, eliminating the need for an electronic control unit. When cooking is stopped, the air curtain evenly directs air downwards, blocking residual fumes; during cooking, it automatically increases the airflow volume on the living room side, enhancing the isolation effect. Coupled with the range hood, it increases the positive pressure at the doorway, improving the efficiency of fume capture and emission, and is adaptable to both closed and open kitchens, as well as open kitchen scenarios. This invention can significantly reduce PM2.5 concentration in the living room, effectively suppressing the cross-space escape of fumes, and has advantages such as simple structure, safety and reliability, low cost, and maintenance-free operation.

Description

Technical Field

[0001] This invention relates to the field of residential ventilation and air purification technology, specifically to a ventilation system and control method for preventing kitchen fumes from escaping across spaces. Background Technology

[0002] In modern homes, the kitchen is a major source of indoor air pollutants. During cooking, the combustion of fuels such as natural gas and liquefied petroleum gas, as well as the cracking and volatilization of cooking oil and food at high temperatures, produce a large amount of complex and highly concentrated pollutants, mainly including PM2.5, ultrafine particulate matter, polycyclic aromatic hydrocarbons, aldehydes and ketones, and volatile organic compounds. These pollutants can cause continuous health damage to the human respiratory, cardiovascular, and immune systems.

[0003] Kitchen fumes are not confined to the kitchen. Due to the temperature difference between indoors and outdoors, the thermal pressure and wind pressure generated by the operation of the range hood and the activities of people, the fumes can easily spread and migrate to other indoor spaces such as the living room and bedroom through building gaps such as door gaps, window gaps, and pipe shafts. This cross-space dispersion of fumes leads to the deterioration of air quality in the entire residential unit, causing cross-contamination in multiple spaces and seriously threatening the health of residents.

[0004] Mechanical ventilation is a key technology for controlling the spread of kitchen fumes and improving indoor air quality. Currently, kitchen ventilation systems generally use range hoods as the main exhaust system. Some technologies create air barriers by setting up directional airflow around the stove or adding an air curtain above the range hood to assist in airflow guidance, thereby improving the efficiency of pollutant capture and emission. However, existing technologies focus on the efficient emission of pollutants within the kitchen and do not provide effective control solutions for the leakage of fumes into other rooms. Especially in common scenarios such as kitchens with open doors, semi-open kitchens, and open-plan kitchens, the lack of reliable fume blocking measures means that the problem of fumes spreading across spaces remains prominent.

[0005] Therefore, existing ventilation devices cannot form a stable and effective airflow isolation when the door is open, resulting in a large amount of oil fume leakage and a wide diffusion range, making it difficult to meet the air quality control requirements of healthy residences. Summary of the Invention

[0006] The purpose of this invention is to provide a ventilation system and control method for preventing kitchen fumes from escaping across spaces. By coupling the main exhaust fan of the range hood with a double-layer air curtain to prevent escaping, the system achieves efficient emission of pollutants and prevents escaping across spaces, thereby improving the health of residential air.

[0007] To achieve the above objectives, the technical solution of this application is as follows: a ventilation system for preventing kitchen fumes from escaping across space, comprising: a main exhaust system for a range hood and a double-layer air curtain device for preventing escaping; the double-layer air curtain device for preventing escaping is disposed above the kitchen door and includes a fan, a main gas chamber, and a secondary gas chamber, wherein the fan is disposed above the main gas chamber and the secondary gas chamber respectively; the main gas chamber and the secondary gas chamber are separated by an intermediate partition plate; a bimetallic strip is disposed on the inner side of the main gas chamber, and the bimetallic strip is connected to the intermediate partition plate through a connecting rod, for sensing changes in airflow temperature and driving the intermediate partition plate to move horizontally, thereby changing the flow cross-sectional area of ​​the main gas chamber and the secondary gas chamber.

[0008] In another embodiment of the present invention, the bimetallic sheet is laminated and composited from brass sheet and Invar sheet; the coefficient of thermal expansion of the brass sheet is greater than that of the Invar sheet, and when the temperature rises, the bimetallic sheet bends toward the Invar sheet.

[0009] In another embodiment of the present invention, a guide vane assembly is connected to the bottom of the intermediate partition plate; the guide vane assembly includes a first guide vane disposed below the main gas chamber and a second guide vane disposed below the auxiliary gas chamber; when the intermediate partition plate moves, it synchronously drives the first guide vane and the second guide vane to rotate, thereby changing the air outlet angle.

[0010] In another implementation of the present invention, the first guide vane and the second guide vane are both linked to the intermediate partition plate via a connecting rod; when the intermediate partition plate moves toward the auxiliary gas chamber, the air outlet angle of the first guide vane and the second guide vane tilts toward the kitchen side.

[0011] In another implementation of the present invention, a first check valve and a second check valve are respectively provided at the air inlets of the main gas chamber and the auxiliary gas chamber.

[0012] In another implementation of the present invention, a first purification chamber and a second purification chamber are respectively provided at the air outlets of the main gas chamber and the auxiliary gas chamber.

[0013] In another implementation of the present invention, the air outlet of the fan is arranged opposite to the air inlets of the main gas chamber and the auxiliary gas chamber located below it, so as to form airflow connection.

[0014] The present invention also provides a control method for preventing kitchen fumes from escaping across a space, applied to the aforementioned ventilation system, comprising: Initial state: The kitchen is not cooking or has stopped cooking, the bimetallic strip is in a straight state, the middle partition is in the center, the main gas compartment and the auxiliary gas compartment have the same space, the first guide vane and the second guide vane have the same angle, and the air curtain is blown downwards evenly. Cooking mode: When cooking is in the kitchen, hot air enters the anti-escape double-layer air curtain device. The bimetallic strip bends due to heat and pushes the middle partition plate towards the auxiliary gas chamber through the connecting rod, making the main gas chamber space larger and the auxiliary gas chamber space smaller. At the same time, it drives the first guide vane and the second guide vane to tilt towards the kitchen side, increasing the air volume and obstruction angle towards the living room side.

[0015] In another implementation of the present invention, during cooking, the main exhaust system of the range hood is coupled with the anti-escape double-layer air curtain device to form a positive pressure airflow barrier in the kitchen door area, preventing the spread of cooking fumes to the living room.

[0016] The present invention also provides an application of the above-mentioned ventilation system for preventing kitchen fumes from escaping across space, used above the doorway connecting the kitchen and living room in a residential building; the main exhaust system of the range hood is used to capture pollutants at the source of cooking, and the anti-escape double-layer air curtain device is used to form an airflow barrier at the doorway to prevent pollutants from escaping across space into the living room.

[0017] By adopting the above technical solution, the present invention can achieve the following technical effects: 1. The anti-escape double-layer air curtain device of the present invention adopts a purely mechanical structure control, without the need for built-in electrical control components. This design completely avoids the safety hazards of electrical components being prone to short circuits, aging, and other failures in the high temperature, high humidity, and greasy environment of the kitchen, thus improving the stability and reliability of equipment operation.

[0018] 2. By eliminating the need for complex electronic sensors, controllers, and related circuitry, this invention not only reduces raw material costs and manufacturing complexity but also decreases subsequent maintenance needs and operating costs. Users do not require professional on-site debugging or replacement of electronic components, solving the problems of complex and costly maintenance associated with traditional electrically controlled air curtain machines.

[0019] 3. By utilizing the thermal response characteristics of the bimetallic strip, this invention achieves fully automatic adaptive adjustment of the airflow parameters. Without manual intervention, the airflow distribution of the air curtain can be matched according to the actual kitchen temperature (i.e., cooking conditions), solving the problems of inconvenience and delayed response of manual adjustment, and ensuring that the oil fume blocking efficiency is always at its optimal state.

[0020] 4. The device adopts a mechanical linkage structure, with a short response link and direct action. The bimetallic strip, when heated, rapidly drives the partition plate and guide vanes, resulting in a fast response. Furthermore, this adjustment process is entirely driven by physical thermal energy, requiring no additional electrical energy consumption, thus achieving zero-energy intelligent control.

[0021] 5. The anti-escape double-layer air curtain device of the present invention is easy to install, does not occupy extra space, and combines practicality and aesthetics, making it easy to promote and install in various residential kitchens.

[0022] 6. By creating a directional high-pressure airflow barrier at the kitchen entrance, this invention effectively prevents cooking fumes from spreading across adjacent spaces such as the living room. While ensuring a healthy living environment, it not only assists the main exhaust system in improving overall smoke extraction efficiency but also significantly reduces the diffusion of pollutants indoors, providing a practical engineering solution for air quality control in healthy homes. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 Schematic diagram of a ventilation system and control method for preventing kitchen fumes from escaping across a space; Figure 2 Schematic diagram of a double-layer air curtain device to prevent leakage; Figure 3 A schematic diagram of the double-layer air curtain device in non-cooking state to prevent leakage; Figure 4 This is a schematic diagram of a bimetallic strip structure; Figure 5 A schematic diagram of the double-layer air curtain device in cooking mode to prevent air leakage; Figure 6 Geometric model diagram for application evaluation of ventilation systems and control methods used to prevent kitchen fumes from escaping across spaces; Figure 7 This is a comparison diagram of the effects of the present invention and a conventional ventilation system under closed conditions; Figure 8 This is a comparison diagram of the effects of the present invention and a conventional ventilation system under door-open conditions; The numbers in the diagram are as follows: 1. Fan; 2. Main gas chamber; 3. Auxiliary gas chamber; 4. First check valve; 5. Bimetallic strip; 6. Connecting rod; 7. First clean chamber; 8. First guide vane; 9. Second check valve; 10. Second clean chamber; 11. Second guide vane; 12. Intermediate partition plate; 13. Brass strip; 14. Invar steel strip. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] The terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature marked with "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0027] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments of the present invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0028] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0029] Example 1 like Figure 1-2As shown, this embodiment provides a ventilation system to prevent kitchen fumes from escaping across spaces. This system uses a range hood as the main exhaust system in the kitchen, where cooking fumes are primarily discharged through the main exhaust system. Simultaneously, a double-layered air curtain device is installed above the doorway connecting the kitchen and living room. This air curtain forms an airflow barrier at the doorway by blowing downwards, preventing pollutants generated during cooking from spreading into the living room. The air curtain device can blow out two layers of airflow, both of which can be independently adjusted in terms of airflow volume and angle. During system operation, the airflow from the air curtain forms a stable isolation layer in the doorway area, blocking the penetration path of kitchen pollutants. The range hood efficiently captures and removes pollutants near the source of cooking. The coupled operation of the main exhaust system and the double-layered air curtain increases positive pressure at the kitchen doorway, promoting airflow towards the range hood exhaust vent, improving the efficiency of the main exhaust system, and preventing kitchen pollutants from penetrating into adjacent rooms or even escaping directly when the door is opened. Overall, this improves the efficiency of pollutant control, enhances indoor air quality, and improves the health of residential buildings.

[0030] This ventilation system mainly includes a main exhaust system for the range hood and a double-layer air curtain device to prevent escaping. The main exhaust system is configured according to the actual conditions of the kitchen, and its structure requires no special requirements. The double-layer air curtain device includes: a fan 1, a main gas chamber 2, and a secondary gas chamber 3. The main gas chamber 2 includes a first check valve 4, a bimetallic strip 5, a connecting rod 6, a first purification chamber 7, and a first guide vane 8. The secondary gas chamber 3 includes a second check valve 9, a second purification chamber 10, and a second guide vane 11. The two chambers are separated by a middle partition plate 12. The bimetallic strip 5 is composed of a brass strip 13 and an Invar strip 14. The coefficient of thermal expansion of the brass strip 13 is much greater than that of the Invar strip 14, allowing it to sense temperature changes and bend. This bending deformation, along with the bending deformation, drives the middle partition plate 12 to move horizontally via the connecting rod 6, simultaneously adjusting the angle of the guide vane to achieve purely mechanical adaptive control.

[0031] Example 2 This embodiment provides a control method for preventing kitchen fumes from escaping across a space, applied to the ventilation system described in Embodiment 1. The main exhaust system of the range hood and the anti-escape double-layer air curtain operate in the following mode: like Figure 3 As shown, when the kitchen is not cooking, the temperature in the kitchen is the same as that in the adjacent rooms. The main exhaust system of the range hood is off, and the bimetallic strip 5 of the anti-escape double-layer air curtain is in a straight, unbent state. The intermediate partition 12 between the main gas chamber 2 and the auxiliary gas chamber 3 is centered, and the main gas chamber 2 and the auxiliary gas chamber 3 have the same space. At this time, if it is necessary to prevent residual fumes in the kitchen from leaking into the adjacent rooms, the fan 1 is started. The air outlet of the fan 1 is evenly distributed to the main gas chamber 2 and the auxiliary gas chamber 3. After passing through the first purification chamber 7 and the second purification chamber 10, the first guide vane 8 and the second guide vane 11 have the same angle, the air volume on both sides is the same, and the air curtain evenly covers the area near the kitchen door.

[0032] like Figure 5 As shown, when cooking is taking place in the galley, hot air diffuses through the gaps into the main gas compartment 2 and the auxiliary gas compartment 3, raising the temperature inside the compartments. Figure 4 As shown, when the temperature rises, the thermal expansion of the brass sheet 13 is much greater than that of the Invar sheet 14. The bimetallic sheet 5 is forced to bend and deform towards the Invar sheet 14, pushing the intermediate partition plate towards the auxiliary gas chamber 3 via the connecting rod 6. After the shift, the space of the main gas chamber 2 becomes larger and the space of the auxiliary gas chamber 3 becomes smaller, allowing more air from the fan to enter the main gas chamber 2. At the same time, the shift of the partition plate synchronously drives the first guide vane 8 and the second guide vane 11 below to rotate. The guide vanes 8 and 11 tilt towards the kitchen side, changing the air supply angle from vertical downward airflow to airflow towards the living room side. The airflow volume on the living room side increases, preventing the spread of cooking fumes into the living room.

[0033] This control method employs a purely mechanical control scheme combining thermo-deformable bimetallic elements and a mechanical linkage mechanism. It utilizes the difference in thermal expansion coefficients of the bimetallic strips to sense the temperature rise during kitchen cooking, and drives the displacement of the intermediate partition plate via a linkage to simultaneously activate the guide vanes, thereby expanding the main gas chamber volume and widening the air outlet area. This automatically increases the blocking air volume without the need for an electronic control unit, achieving adaptive matching between the air curtain outlet parameters and the kitchen pollution status through thermo-coupling and purely mechanical response.

[0034] Example 3 This embodiment provides a specific application of the ventilation system described in Embodiment 1, and verifies its effectiveness through performance evaluation.

[0035] like Figure 6 As shown, the ventilation system is applied to a residential kitchen, which is 2.6m long, 1.6m wide, and 2.6m high. The kitchen is equipped with a range hood, cooking pots, cabinets, a sink, and doors and windows. The adjacent functional room is a living room, which is 8m long, 4m wide, and 2.8m high. The living room is equipped with a television, sofa, coffee table, lighting fixtures, and doors. The kitchen's exhaust system includes a main exhaust system located above the stove and a double-layered air curtain above the kitchen door on the living room side. Both layers have exhaust vents that are 1.21m long and 0.1m wide.

[0036] The study focused on PM2.5 particles generated during kitchen cooking. The PM2.5 release rate was 140 μg / s, and the release process was divided into three stages: an initial 2 minutes as a preheating stage with no release; a subsequent 10 minutes of continuous release; and a final 8 minutes where release ceased. During this period, the main exhaust system of the range hood and the anti-escape double-layer air curtain operated continuously for a total duration of 20 minutes.

[0037] The experimental results show that: Figure 7As shown, when the kitchen door is closed, compared with a conventional range hood exhaust system, the PM2.5 concentration at the sitting breathing height in the living room decreases from 23.4 μg / m³. 3 Reduced to 13.1 μg / m 3 The decrease was 41.12%; the peak PM2.5 concentration in the breathing zone of cooks in the kitchen decreased from 198.72 μg / m³. 3 Reduced to 180.65 μg / m 3 The decrease was 9.09%. For example... Figure 8 As shown, when the kitchen door was open, the PM2.5 concentration at the seated breathing height in the living room increased from 52.3 μg / m³. 3 Reduced to 31.5 μg / m 3 The decrease was 38.70%; the peak PM2.5 concentration in the breathing zone of kitchen workers decreased from 117.34 μg / m³. 3 Decreased to 107.14 μg / m 3 The decrease was 8.69%.

[0038] This ventilation system effectively solves the problem that existing mechanical ventilation systems only focus on emissions within the kitchen and cannot address the issue of cooking fumes escaping across spaces in open or enclosed kitchens. Specifically, the main exhaust system of the range hood centrally discharges major cooking pollutants, while a double-layered air curtain enhances the efficiency of the main exhaust and prevents fumes from escaping to other rooms. It can be used stably with kitchen doors closed, open, and in open kitchen scenarios, significantly reducing the amount of pollutants leaking across spaces, promoting efficient emissions of kitchen pollutants, and providing an engineering solution for controlling air quality in healthy residential kitchens.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A ventilation system for preventing kitchen fumes from escaping across a space, characterized in that, It includes a main exhaust system for a range hood and a double-layer air curtain device to prevent escaping; the double-layer air curtain device is located above the kitchen door and includes a fan (1), a main gas chamber (2) and a secondary gas chamber (3). The fan (1) is located above the main gas chamber (2) and the secondary gas chamber (3) respectively. The main gas chamber (2) and the secondary gas chamber (3) are separated by a middle partition plate (12). A bimetallic strip (5) is provided on the inner side of the main gas chamber (2). The bimetallic strip (5) is connected to the middle partition plate (12) through a connecting rod (6) to sense changes in airflow temperature and drive the middle partition plate (12) to move horizontally, thereby changing the flow cross-sectional area of ​​the main gas chamber (2) and the secondary gas chamber (3).

2. The ventilation system for preventing kitchen fumes from escaping across a space according to claim 1, characterized in that, The bimetallic sheet (5) is laminated with a brass sheet (13) and an Invar sheet (14); the coefficient of thermal expansion of the brass sheet (13) is greater than that of the Invar sheet (14), and when the temperature rises, the bimetallic sheet (5) bends toward the Invar sheet (14).

3. The ventilation system for preventing kitchen fumes from escaping across a space according to claim 1, characterized in that, The bottom of the intermediate partition plate (12) is connected to a guide vane assembly; the guide vane assembly includes a first guide vane (8) disposed below the main gas chamber (2) and a second guide vane (11) disposed below the auxiliary gas chamber (3); when the intermediate partition plate (12) moves, it synchronously drives the first guide vane (8) and the second guide vane (11) to rotate, changing the air outlet angle.

4. A ventilation system for preventing kitchen fumes from escaping across a space, as described in claim 3, is characterized in that... The first guide vane (8) and the second guide vane (11) are linked to the intermediate partition plate (12) through a connecting rod; when the intermediate partition plate (12) moves toward the auxiliary gas chamber (3), the air outlet angle of the first guide vane (8) and the second guide vane (11) tilts toward the kitchen side.

5. A ventilation system for preventing kitchen fumes from escaping across a space, as described in claim 1, is characterized in that... The main gas chamber (2) and the auxiliary gas chamber (3) are respectively equipped with a first check valve (4) and a second check valve (9) at their air inlets.

6. A ventilation system for preventing kitchen fumes from escaping across a space, as described in claim 1, is characterized in that... The main gas chamber (2) and the auxiliary gas chamber (3) are respectively provided with a first purification chamber (7) and a second purification chamber (10) at their air outlets.

7. A ventilation system for preventing kitchen fumes from escaping across a space, as described in claim 5, is characterized in that... The air outlet of the fan (1) is positioned opposite to the air inlets of the main gas chamber (2) and the auxiliary gas chamber (3) located below it, so as to form airflow connection.

8. A control method for preventing kitchen fumes from escaping across a space, applied to the ventilation system of any one of claims 17, characterized in that, include: Initial state: The kitchen is not cooking or has stopped cooking, the bimetallic strip is in a straight state, the middle partition (12) is in the center, the main gas compartment (2) and the auxiliary gas compartment (3) have the same space, the first guide vane (8) and the second guide vane (11) have the same angle, and the air curtain blows out evenly downwards; Cooking status: Cooking is being carried out in the kitchen. Hot air enters the anti-escape double-layer air curtain device. The bimetallic strip is bent by heat and pushes the middle partition plate (12) to shift towards the auxiliary gas chamber (3) through the connecting rod, making the space of the main gas chamber (2) larger and the space of the auxiliary gas chamber (3) smaller. At the same time, it drives the first guide vane (8) and the second guide vane (11) to tilt towards the kitchen side, increasing the air volume and blocking angle towards the living room side.

9. The control method for preventing kitchen fumes from escaping across space according to claim 8, characterized in that, When cooking, the main exhaust system of the range hood and the anti-escape double-layer air curtain device work together to form a positive pressure airflow barrier in the kitchen door area, preventing the spread of cooking fumes into the living room.

10. An application of a ventilation system for preventing kitchen fumes from escaping across a space as described in any one of claims 1-7, characterized in that, It is used above the doorway connecting the kitchen and living room in a residential building; The main exhaust system of the range hood is used to capture pollutants at the source of cooking, and the anti-escape double-layer air curtain device is used to form an airflow barrier at the doorway to prevent pollutants from escaping across the living room.

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