Air guide mechanism, refrigeration type range hood and control method

Abstract

A kind of air guide mechanism, refrigeration type range hood and control method, the air guide mechanism includes outer frame and the grid assembly installed in outer frame, grid assembly can be moved relative to outer frame under the impact of airflow, elastic member is provided between grid assembly and outer frame, the direction of force of elastic member to grid assembly is opposite to the moving direction of grid assembly under the impact of airflow, grid assembly includes the air guide fin of interval distribution, the windward surface of air guide fin is flexible curved surface, air guide fin has air guide fin inner cavity that can guide into external gas, flexible curved surface is deformed accordingly with the air pressure change inside air guide fin inner cavity, change air guide fin air outlet direction, the refrigeration type range hood is installed with air guide mechanism at the side wall vent of fan frame, to adjust hot end air outlet area and air outlet direction.The refrigeration type range hood control method can comprehensively control the relevant balance of range hood main air inlet, hot end air inlet, and minimize the interference of heat dissipation airflow to the internal flow field of range hood, to ensure the effect of range hood.

Description

Technical Field

[0001] This invention relates to range hoods, and more particularly to an air guiding mechanism, a refrigerated range hood, and a control method. Background Technology

[0002] In hot weather or during cooking, the temperature in the cooking area can easily rise, reducing the user's cooking experience. To solve this problem, cooling range hoods were invented. These hoods integrate a cooling function to lower the temperature in the cooking area. When operating in cooling mode, the heat dissipation module generates heat and needs to be dissipated. Currently, the heat dissipation channel of the heat dissipation module is connected to the exhaust duct, and the heat from the heat dissipation module is exhausted through the exhaust duct. For example, the Chinese utility model patent with patent number 202222717737.8 (authorization announcement number CN 218864269 U) discloses a "Refrigerated Range Hood". This refrigerated range hood includes a casing, an exhaust chamber inside the casing, a range hood fan installed inside the exhaust chamber, and a compressor, condenser, and evaporator installed outside the exhaust chamber. The compressor, condenser, and evaporator are connected through refrigerant pipes. A heat dissipation channel and an air outlet channel are provided inside the casing and outside the exhaust chamber. The condenser is located in the heat dissipation channel, and the air outlet of the heat dissipation channel is connected to the exhaust chamber. The evaporator is located in the air outlet channel. The heat from the condenser is discharged to the outside through the heat dissipation channel and the exhaust chamber. Common heat dissipation solutions for existing refrigerated range hoods include: 1. Connecting the heat dissipation outlet of the heat dissipation module to the high-pressure area of ​​the range hood casing. Although this heat dissipation method does not affect the internal flow field of the range hood and does not interfere with the range hood's smoke extraction effect, it is extremely expensive. 2. The heat dissipation outlet is connected to the low-pressure area of ​​the range hood casing. While this method is low-cost and relatively simple in structure, the direct connection between the heat dissipation outlet and the exhaust duct can easily interfere with the internal airflow of the range hood, affecting its smoke extraction performance. In conclusion, existing cooling-type range hoods require further improvement. Summary of the Invention

[0003] The first technical problem to be solved by the present invention is to provide an air guiding mechanism that can adjust the air outlet area and air outlet direction, in view of the above-mentioned existing technology.

[0004] The second technical problem to be solved by the present invention is to provide a cooling range hood that can adjust the air outlet area and air outlet direction of the hot end air outlet, in view of the above-mentioned existing technology.

[0005] The third technical problem to be solved by the present invention is to provide a control method for a refrigerated range hood that can comprehensively control the main air intake, the hot end air intake, and reduce the interference of the internal flow field of the range hood, in view of the above-mentioned existing technology.

[0006] The technical solution adopted by the present invention to solve the first technical problem mentioned above is as follows: an air guiding mechanism, comprising an outer frame and a grille assembly installed inside the outer frame, characterized in that: the grille assembly can move relative to the outer frame under the impact of airflow, an elastic element is provided between the grille assembly and the outer frame, the direction of the force exerted by the elastic element on the grille assembly is opposite to the direction of movement of the grille assembly under the impact of airflow, the grille assembly includes spaced air guiding vanes, the windward surface of the air guiding vanes is a flexible curved surface, the air guiding vanes have an inner cavity that can introduce external gas, the flexible curved surface deforms accordingly with the change of air pressure inside the inner cavity of the air guiding vanes, thereby changing the air outlet direction of the air guiding vanes.

[0007] The grille assembly can have various structures. Preferably, the grille assembly includes a movable frame, on which a rack is mounted. The rack is arranged along the moving direction of the movable frame, and each of the air guide vanes has a gear at its end that meshes with the rack.

[0008] In order to close the air guide vane, a one-way damper is installed on the movable frame to tend the air guide vane to the closed state, and the output shaft of the one-way damper is mounted on one of the gears.

[0009] The elastic element can have various structures. Preferably, the elastic element is a compression spring disposed between the movable frame and the outer frame.

[0010] To guide the movement of the movable frame, the outer frame and the movable frame have a mutually cooperating sliding guide structure. For example, a groove can be formed on the outer frame, and a slide rail that can slide within the groove can be provided on the movable frame; or, a groove can be formed on the movable frame, and a slide rail that can slide within the groove can be provided on the outer frame.

[0011] The technical solution adopted by the present invention to solve the second technical problem mentioned above is as follows: a refrigerated range hood, comprising a casing, a fan frame installed inside the casing, a range hood fan installed inside the fan frame, and a compressor, a heat dissipation module, and a refrigeration module installed inside the casing and outside the fan frame. The feature is that a ventilation opening is provided on the side wall of the fan frame, the air outlet of the heat dissipation module is connected to the air inlet of the range hood fan through the ventilation opening, and a guide mechanism is installed at the ventilation opening to adjust the air outlet area and air outlet direction of the ventilation opening.

[0012] In order to blow cool air out of the range hood casing, the heat dissipation module includes a condenser and a cooling fan. The air outlet of the cooling fan is connected to the ventilation port through an air guide shroud. The refrigeration module includes an evaporator and an air outlet fan. An air conditioning outlet is opened on the casing, and the air outlet fan is connected to the air conditioning outlet.

[0013] In order to enable the air guide vane to adjust its outer contour according to the air pressure, thereby changing the interception area and lift, and thus changing the air intake direction, an air pressure guide pipe is provided on the outside of the fan frame. A pressure control valve is installed on the air pressure guide pipe. One end of the air pressure guide pipe is connected to the inner cavity of the air guide vane of the air guide mechanism, and the other end of the air pressure guide pipe is connected to the air outlet of the fume extractor.

[0014] To achieve intelligent control of the cooling fan, the range hood fan, and the pressure control valve, a first wind speed sensor is installed at the main air inlet of the range hood, a second wind speed sensor is installed at the air outlet of the range hood, and a temperature sensor for detecting the condenser temperature is installed on the heat dissipation module. The system also includes a controller. The signal output terminals of the first wind speed sensor, the second wind speed sensor, and the temperature sensor are all electrically connected to the signal input terminal of the controller. The controller can control the speed of the cooling fan, the speed of the range hood fan, and the opening degree of the pressure control valve according to the received signals.

[0015] The technical solution adopted by the present invention to solve the third technical problem mentioned above is: a control method for a range hood, characterized in that: the control method is applied to the aforementioned refrigerated range hood, and the control method includes the following steps: 1) Turn on the range hood; 2) Determine if the cooling mode is turned on; If enabled, the cooling fan will turn on, and then proceed to step 3). If not opened, the pressure control valve will be closed and the cooling fan will be shut off; 3) Determine the relationship between the condenser temperature T detected by the temperature sensor and the critical temperature T1. Calculate the corresponding main air inlet airflow Q1 based on the wind speed detected by the first wind speed sensor, and calculate the corresponding outlet airflow Q2 based on the wind speed detected by the second wind speed sensor. Determine the relationship between Q1 and the first critical airflow Q1', and the relationship between Q2 and the second critical airflow Q2'. The critical temperature T1 is the maximum limiting temperature of the condenser, the first critical airflow Q1' is the minimum airflow of the main air inlet to meet the no-smoke emission condition, and the second critical airflow Q2' is the maximum airflow of the outlet to meet the operating noise condition of the range hood. If T > T1, Q1 < Q1', and Q2 > Q2', then maintain the cooling fan speed, increase the pressure control valve opening, and then return to step 3). If T < T1, Q1 > Q1', and Q2 > Q2', then reduce the cooling fan speed and return to step 3). If T < T1, Q1 > Q1' and Q2 < Q2', then maintain the current opening of the pressure control valve, maintain the current speed of the cooling fan, and maintain the current speed of the fume extraction fan. If T > T1, Q1 > Q1' and Q2 < Q2', then determine whether the current speed of the cooling fan is less than the maximum achievable critical speed of the cooling fan. If the current speed is less than the critical speed, then increase the current speed of the cooling fan. If the current speed is equal to the critical speed, then increase the opening of the pressure control valve. If T < T1, Q1 < Q1', and Q2 < Q2', then reduce the speed of the cooling fan (522), reduce the hot end airflow Q3, where Q3 = Q1 - Q2, and then return to step 3). If T > T1, Q1 < Q1', and Q2 < Q2', then increase the speed of the fume extractor fan, increase the air volume at the outlet Q2, and then return to step 3).

[0016] Compared with the prior art, the advantages of this invention are as follows: This cooling range hood adopts an air guide mechanism that can adjust the air outlet area and air outlet direction. The air guide vane is hollow inside and can aerodynamically change the wing contour. The air guide vane assembly changes the position of the grille assembly by different wing shapes and different lift on the left and right sides. The area of ​​the hot end air outlet can be steplessly adjusted, and the outer contour of the hot end air outlet wing guide vane can be aerodynamically adjusted to change the interception area and lift, thereby changing the air intake direction. The control method of this cooling range hood can comprehensively control the relevant balance of the main air intake and the hot end air intake of the heat dissipation module, ensuring that the range hood can automatically adjust the hot end air intake reasonably under different working conditions and different pressures, ensuring the smoke extraction effect while ensuring the heat dissipation requirements of the cooling system, and minimizing the interference of the heat dissipation airflow on the internal flow field of the range hood. At the same time, this air guide mechanism has no additional motor drive structure, which is low in cost, reliable, and can realize stepless automatic adjustment of the air outlet area and direction. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the air guide mechanism according to an embodiment of the present invention; Figure 2 for Figure 1 The diagram shows the air guide mechanism without its outer frame. Figure 3 This is a schematic diagram of the air guide vane in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a refrigerated range hood according to an embodiment of the present invention; Figure 5 for Figure 4 The diagram shows the structure of the range hood from another angle; Figure 6 for Figure 4 The diagram shows the structure of the range hood after the casing has been removed. Figure 7 for Figure 6 The diagram shows the structure of the range hood from another angle; Figure 8 This is a schematic diagram of the connection of the air conditioning components according to an embodiment of the present invention; Figure 9 This is a flowchart illustrating the control method according to an embodiment of the present invention. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0019] like Figures 1 to 3 As shown, the air guiding mechanism of this embodiment includes an outer frame 11 and a grille assembly 12 installed inside the outer frame 11. The grille assembly 12 includes a movable frame 122 and spaced-apart air guiding plates 121. The outer frame 11 and the movable frame 122 have mutually cooperating sliding guide structures. For example, a groove can be formed on the outer frame 11, and a slide rail that can slide within the groove can be provided on the movable frame 122; or, a groove can be formed on the movable frame 122, and a slide rail that can slide within the groove can be provided on the outer frame 11. Through the cooperation of the groove and the slide rail, the movable frame 122 can easily slide along the outer frame 11 under the action of external force. Figure 1 The direction indicated by arrow A is backward. A compression spring 126 is installed between the rear side of the movable frame 122 and the outer frame 11. The compression spring 126 keeps the grille assembly 12 inclined to move forward. Figure 3 As shown, one side of the air guide vane 121 is flat, and the other side is curved, i.e., it adopts an airfoil-shaped air guide vane. When the airflow passes along the two sides of the air guide vane 121 along arrows B and C, it generates lift acting on the flat side of the air guide vane. Figure 1 and Figure 2 It can be seen that the lift force can make the air guide vane 121 move backward, that is, the direction of the force exerted by the compression spring 126 on the grille assembly 12 is opposite to the direction of movement of the grille assembly 12 under the impact of airflow.

[0020] In this embodiment, a rack 123 is mounted on the movable frame 122, and the rack 123 is arranged along the moving direction of the movable frame 122. Each air guide vane 121 has a gear 124 at its end that meshes with the rack 123. Therefore, under the impact of airflow and the action of lift, all air guide vanes 121 can move synchronously, that is, the grille assembly 12 can move relative to the outer frame 11 under the impact of airflow.

[0021] A one-way damper 125 is installed on the movable frame 122 to tend towards the closed state of the air guide vanes 121. The output shaft of the one-way damper 125 is mounted on one of the gears 124. Since all gears 124 can be linked, under the action of the one-way damper 125, all air guide vanes 121 can be made to close synchronously. In this embodiment, when the air guide vanes 121 are closed, the curved surface is the windward surface. When the airflow passes through the air guide vanes 121, it will generate an impact force that impacts the curved surface of the air guide vanes. This impact force causes the air guide vanes 121 to tend to open. If the impact force is greater than the resistance of the one-way damper, the air guide vanes open, and the greater the impact force, the greater the opening angle of the air guide vanes 121. If the impact force is less than the resistance of the one-way damper, the air guide vanes 121 close. Furthermore, in this embodiment, the windward surface of the air guide 121 is a flexible curved surface. The air guide 121 has an inner cavity that can introduce external gas. The flexible curved surface deforms accordingly with the change of air pressure inside the inner cavity of the air guide, thereby changing the air outlet direction of the air guide 121. For example, when the gas pressure inside the inner cavity of the air guide increases, the curved surface of the air guide 121 expands, thereby changing the force on the air guide 121 and further steplessly adjusting the air outlet direction of the air guide mechanism. At the same time, the larger the curved surface of the air guide 121, the greater the lift.

[0022] like Figures 4 to 8 As shown, the cooling range hood of this embodiment integrates an air conditioning component into the range hood. Specifically, it includes a housing 2, a fan frame 3 installed inside the housing 2, and a range hood fan 4 installed inside the fan frame 3. A compressor 51, a heat dissipation module 52, and a cooling module 53 are installed inside the housing 2 and outside the fan frame 3. The heat dissipation module 52 includes a condenser 521 and a cooling fan 522, and the cooling module 53 includes an evaporator 531 and an outlet fan 532. The compressor 51, condenser 521, and evaporator 531 are connected via refrigerant piping. Their working principle can be referenced from existing air conditioners and will not be described in detail here. An air conditioning outlet 21 is opened on the housing 2, and the outlet of the outlet fan 532 is connected to the air conditioning outlet 21. During cooling, cold air is blown out from the housing 2.

[0023] In this embodiment, a ventilation opening is provided on the side wall of the fan frame 3. The air outlet of the cooling fan 522 is connected to the ventilation opening through the air guide shroud 523. Thus, the air outlet of the cooling fan 522 is connected to the air inlet of the fume extractor 4 through the ventilation opening. The air guide mechanism 1 is installed at the ventilation opening. Under the action of the lift and the spring force of the compression spring 126, the front and rear positions of the grille assembly 12 are adjusted, thereby changing the ventilation area of ​​the ventilation opening, i.e., the area of ​​the hot end air inlet. An air pressure guide pipe 6 is provided on the outside of the fan frame 3. A pressure control valve 7 is installed on the air pressure guide pipe 6. One end of the air pressure guide pipe 6 is connected to the inner cavity of the air guide vane of the air guide mechanism 1, and the other end of the air pressure guide pipe 6 is connected to the air outlet of the fume extractor 4. The airflow from the air outlet of the fume extractor 4 can enter the inner cavity of the air guide vane, thereby changing the profile of the air guide vane 121 according to different air pressures and adjusting the air outlet direction of the air guide mechanism 1. When the cooling is off, there is no airflow to dissipate heat at the hot end air inlet, and the air guide vane 121 closes due to the resistance of the one-way damper 125, thereby preventing oil fumes from polluting the condenser 521.

[0024] A first wind speed sensor 81 is installed at the main air inlet of the range hood. This sensor detects the wind speed at the main air inlet and calculates the airflow Q1 based on this speed. The airflow Q1 must meet the minimum requirement for preventing smoke escape; that is, Q1 must be greater than the first critical airflow Q1'. A second wind speed sensor 82 is installed at the air outlet of the range hood. This sensor detects the wind speed at the outlet and calculates the airflow Q2 based on this speed. The airflow Q2 must be less than the airflow under maximum noise conditions; that is, Q2 must be less than the second critical airflow Q2'. Furthermore, based on the airflow Q1 and Q2, the airflow at the vent, i.e., the hot-end airflow Q3, can be calculated as Q3 = Q2 - Q1. In addition, a temperature sensor 9 is installed on the heat dissipation module 52 to detect the temperature of the condenser 521. In order to ensure the cooling effect, the condenser temperature T needs to be lower than the critical temperature T1. When the condenser temperature T reaches the critical temperature T1, the air conditioner's energy efficiency decreases. At this time, it is necessary to increase the speed of the cooling fan 522 to accelerate the heat dissipation effect on the condenser 521 and reduce the condenser temperature T.

[0025] In this embodiment, the signal output terminals of the first wind speed sensor 81, the second wind speed sensor 82, and the temperature sensor 9 are all electrically connected to the signal input terminal of the controller. The controller can control the speed of the cooling fan 522, the speed of the fume extractor fan 4, and the opening degree of the pressure control valve 7 according to the received signals.

[0026] like Figure 9 As shown, the control method for the refrigerated range hood in this embodiment includes the following steps: 1) Turn on the range hood; 2) Determine if the cooling mode is turned on; If activated, cooling fan 522 will turn on, and then proceed to step 3). If not opened, pressure control valve 7 will be closed and cooling fan 522 will be shut off; 3) Determine the relationship between the condenser temperature T detected by temperature sensor 9 and the critical temperature T1. Calculate the corresponding main air inlet airflow Q1 based on the wind speed detected by the first wind speed sensor 81, and calculate the corresponding outlet airflow Q2 based on the wind speed detected by the second wind speed sensor 82. Determine the relationship between Q1 and the first critical airflow Q1', and the relationship between Q2 and the second critical airflow Q2'. The critical temperature T1 is the maximum limiting temperature of the condenser, the first critical airflow Q1' is the minimum airflow of the main air inlet under the condition of no smoke leakage, and the second critical airflow Q2' is the maximum airflow of the outlet under the condition of no noise during the operation of the range hood. If T > T1, Q1 < Q1', and Q2 > Q2', then maintain the cooling fan speed of 522, increase the opening of pressure control valve 7, and then return to step 3). If T < T1, Q1 > Q1', and Q2 > Q2', then reduce the speed of the cooling fan 522 and return to step 3). If T < T1, Q1 > Q1' and Q2 < Q2', then maintain the current opening of pressure control valve 7, maintain the current speed of cooling fan 522, and maintain the current speed of fume extraction fan 4; If T > T1, Q1 > Q1' and Q2 < Q2', then determine whether the current speed of the cooling fan 522 is less than the maximum achievable critical speed of the cooling fan 522. If the current speed is less than the critical speed, then increase the current speed of the cooling fan 522. If the current speed is equal to the critical speed, then increase the opening of the pressure control valve 7. If T < T1, Q1 < Q1', and Q2 < Q2', then reduce the speed of the cooling fan (522), reduce the hot end airflow Q3, where Q3 = Q1 - Q2, and then return to step 3). If T > T1, Q1 < Q1', and Q2 < Q2', then increase the speed of the range hood 4, increase the air volume Q2 at the outlet, and then return to step 3).

[0027] exist Figure 3 As shown, T1 critical is the critical temperature T1, Q1 critical is the first critical temperature Q1', Q2 critical is the second critical air volume Q2', and S critical is the maximum achievable critical speed of the cooling fan.

[0028] As can be seen from the above control method, this control method collects the wind speed at the main air inlet, the wind speed at the main air outlet, and the condenser temperature T, and controls the curvature of the guide vane 121 through the pressure control valve 7, thereby adjusting the force and angle of the guide vane 121, thus achieving the optimal values ​​of Q1, Q2, and Q3. It controls the position of the hot end air inlet relative to the volute air inlet of the range hood 4, controls the air inlet area at the heat dissipation end, and adjusts the stepless adjustment of the hot end air inlet wind speed and the air outlet angle of the guide vane, thereby reducing turbulence under different operating conditions.

[0029] When the cooling function is off, the air guide vane 121 is closed to prevent backflow of fumes and contamination of the condenser 521. When the cooling function is on, the air guide vane 121 opens, and the heat from the condenser 521 enters the exhaust fan 4 through the cooling fan 522, and is ultimately exhausted through the exhaust fan 4. When the back pressure of the range hood is high, the grille assembly 12 moves backward to increase the area of ​​the hot-end air inlet, reduce internal turbulence, and ensure effective fume extraction.

[0030] The specification and claims of this invention use terms indicating direction, such as "front," "rear," "upper," "lower," "left," "right," "side," "top," and "bottom," to describe various exemplary structural parts and elements of the invention. However, these terms are used herein merely for ease of explanation and are determined based on the exemplary orientations shown in the accompanying drawings. Since the embodiments disclosed in this invention can be arranged in different orientations, these terms indicating direction are for illustrative purposes only and should not be considered as limitations. For example, "upper" and "lower" are not necessarily limited to directions opposite to or consistent with the direction of gravity.

Claims

1. An air guiding mechanism, comprising an outer frame (11) and a grille assembly (12) installed within the outer frame (11), characterized in that: The grille assembly (12) can move relative to the outer frame (11) under the impact of airflow. An elastic element is provided between the grille assembly (12) and the outer frame (11). The direction of the force exerted by the elastic element on the grille assembly (12) is opposite to the direction of movement of the grille assembly (12) under the impact of airflow. The grille assembly (12) includes spaced-apart guide vanes (121) and wind deflectors located on the outside of the guide vanes. The first side of the guide vane (121) is a flexible curved surface, and the second side of the guide vane is a plane. When the airflow passes through the two sides of the guide vane, it generates a lift force acting on the plane side of the guide vane. The guide vane (121) has a guide vane cavity (1211) that can introduce external gas. The flexible curved surface deforms accordingly with the change of air pressure inside the guide vane cavity (1211), thereby changing the airflow. The air outlet direction of the air guide vane (121); the grille assembly (12) includes a movable frame (122), on which a rack (123) is mounted, the rack (123) is arranged along the moving direction of the movable frame (122), and each end of the air guide vane (121) is equipped with a gear (124) that meshes with the rack (123); a one-way damper (125) is mounted on the movable frame (122) to make the air guide vane (121) tend to be closed, and the output shaft of the one-way damper (125) is mounted on one of the gears (124); the outer frame (11) and the movable frame (122) have a sliding guide structure that cooperates with each other, and the movable frame (122) can slide along the outer frame (11) under the action of external force.

2. The air guiding mechanism according to claim 1, characterized in that: The elastic element is a compression spring (126) located between the movable frame (122) and the outer frame (11).

3. A refrigerated range hood, comprising a housing (2), a fan frame (3) installed inside the housing (2), a range hood fan (4) installed inside the fan frame (3), and a compressor (51), a heat dissipation module (52), and a refrigeration module (53) installed inside the housing (2) and outside the fan frame (3), characterized in that: Ventilation openings are provided on the side wall of the fan frame (3). The air outlet of the heat dissipation module (52) is connected to the air inlet of the fume extractor (4) through the ventilation openings. The air guiding mechanism (1) described in claim 1 or 2 is installed at the ventilation openings. The air outlet area and air outlet direction of the ventilation openings are adjusted by the air guiding mechanism (1).

4. The refrigerated range hood according to claim 3, characterized in that: The heat dissipation module (52) includes a condenser (521) and a heat dissipation fan (522). The air outlet of the heat dissipation fan (522) is connected to the ventilation port through the air guide shroud (523). The refrigeration module (53) includes an evaporator (531) and an air outlet fan (532). An air conditioning air outlet (21) is opened on the casing (2). The air outlet of the air outlet fan (532) is connected to the air conditioning air outlet (21).

5. The refrigerated range hood according to claim 4, characterized in that: A pressure guide pipe (6) is provided on the outside of the fan frame (3). A pressure control valve (7) is installed on the pressure guide pipe (6). One end of the pressure guide pipe (6) is connected to the inner cavity (1211) of the air guide plate of the air guide mechanism (1), and the other end of the pressure guide pipe (6) is connected to the air outlet of the fume extractor (4).

6. The refrigerated range hood according to claim 5, characterized in that: A first wind speed sensor (81) is installed at the main air inlet of the range hood, and a second wind speed sensor (82) is installed at the air outlet of the range hood fan (4). A temperature sensor (9) for detecting the temperature of the condenser (521) is installed on the heat dissipation module (52). The range hood also includes a controller. The signal output terminals of the first wind speed sensor (81), the second wind speed sensor (82), and the temperature sensor (9) are all electrically connected to the signal input terminal of the controller. The controller can control the speed of the heat dissipation fan (522), the speed of the range hood fan (4), and the opening degree of the pressure control valve (7) according to the received signals.

7. A control method for a range hood, characterized in that: This control method is applied to the refrigerated range hood according to claim 6, and the control method includes the following steps: 1) Turn on the range hood; 2) Determine if the cooling mode is turned on; If turned on, the cooling fan (522) will turn on, and then proceed to step 3). If not opened, the pressure control valve (7) will be closed and the cooling fan (522) will be closed; 3) Determine the relationship between the condenser temperature T detected by the temperature sensor (9) and the critical temperature T1. Calculate the corresponding main air inlet air volume Q1 based on the wind speed detected by the first wind speed sensor (81). Calculate the corresponding air outlet air volume Q2 based on the wind speed detected by the second wind speed sensor (82). Determine the relationship between Q1 and the first critical air volume Q1', and the relationship between Q2 and the second critical air volume Q2'. The critical temperature T1 is the maximum limiting temperature of the condenser. The first critical air volume Q1' is the minimum air volume of the main air inlet under the condition of no smoke leakage. The second critical air volume Q2' is the maximum air volume of the air outlet under the condition of no noise during the operation of the range hood. If T > T1, Q1 < Q1' and Q2 > Q2', then maintain the speed of the cooling fan (522), increase the opening of the pressure control valve (7), and then return to step 3). If T < T1, Q1 > Q1' and Q2 > Q2', then reduce the speed of the cooling fan (522) and then return to step 3). If T < T1, Q1 > Q1' and Q2 < Q2', then maintain the current opening of the pressure control valve (7), maintain the current speed of the cooling fan (522), and maintain the current speed of the fume extractor (4); If T > T1, Q1 > Q1' and Q2 < Q2', then determine whether the current speed of the cooling fan (522) is less than the maximum achievable critical speed of the cooling fan (522). If the current speed is less than the critical speed, then increase the current speed of the cooling fan (522). If the current speed is equal to the critical speed, then increase the opening of the pressure control valve (7). If T < T1, Q1 < Q1', and Q2 < Q2', then reduce the speed of the cooling fan (522), reduce the hot end airflow Q3, where Q3 = Q1 - Q2, and then return to step 3). If T > T1, Q1 < Q1' and Q2 < Q2', then increase the speed of the fume extractor (4), increase the air volume at the outlet Q2, and then return to step 3).

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