Range hood

Abstract

The range hood comprises a rack assembly and a fan assembly, and an oil smoke suction opening is formed in the bottom of the rack assembly; the fan assembly is arranged in the rack assembly, the fan assembly is provided with a main air suction port and an auxiliary air suction port which are communicated with the oil smoke suction port, and an air outlet which is communicated with the main air suction port and the auxiliary air suction port, the main air suction port is arranged towards the front side of the rack assembly, and the auxiliary air suction port is arranged towards the rear side of the rack assembly. The auxiliary exhaust inlet is arranged towards the rear side of the rack assembly, and the air outlet is arranged towards the top side of the rack assembly; wherein the center O of the main exhaust inlet and the center P of the auxiliary exhaust inlet do not coincide with each other, and the overall noise of the range hood can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrical appliances, in particular to a range hood. BACKGROUND

[0002] With the continuous improvement of modern families' pursuit of life quality, the range hood has become one of the indispensable devices in the kitchen. The main function of the range hood is to exhaust the oil fume, odor and steam generated during the cooking process to the outside, so as to keep the kitchen environment clean and sanitary.

[0003] The range hood usually comprises a rack assembly and a smoke collecting assembly, wherein the rack assembly is used to support the fan, and the smoke collecting assembly is responsible for collecting and guiding the oil fume to the fan cavity. However, when the fan rotates at high speed, the friction between the blade and the air will generate airflow noise. This part of noise will be concentrated in the range hood and will be emitted from all around the range hood, resulting in a large overall noise of the range hood. SUMMARY

[0004] The embodiments of the present application provide a range hood capable of reducing the overall noise of the range hood.

[0005] The embodiments of the present application provide a range hood, comprising a rack assembly and a fan assembly, wherein the bottom of the rack assembly is provided with a range hood inlet; the fan assembly is arranged in the rack assembly, and the fan assembly is provided with a main air inlet and an auxiliary air inlet communicated with the range hood inlet, and an air outlet communicated with the main air inlet and the auxiliary air inlet, the main air inlet is arranged towards the front side of the rack assembly, the auxiliary air inlet is arranged towards the rear side of the rack assembly, and the air outlet is arranged towards the upper side of the rack assembly; wherein the center O of the main air inlet and the auxiliary air inlet is not coincident with the center P of the rack assembly.

[0006] In some embodiments, the fan assembly comprises a multi-wing centrifugal fan wheel, and the rotation direction of the multi-wing centrifugal fan wheel is clockwise when viewed from the front of the range hood, and the fan blades of the multi-wing centrifugal fan wheel are forward blades.

[0007] In some embodiments, the center O of the main air inlet and the auxiliary air inlet is located on the right side of the center P of the rack assembly.

[0008] And / or, the center O of the main air inlet and the auxiliary air inlet is located on the upper side of the center P of the rack assembly.

[0009] In some embodiments, the rack assembly has a dimension W in the left-right direction and a dimension L in the up-down direction, the center O of the main air inlet and the auxiliary air inlet is located at the upper right side of the center P of the rack assembly, the vertical distance between the center O of the main air inlet and the auxiliary air inlet and the center P of the rack assembly is L1, and the horizontal distance between the center O of the main air inlet and the auxiliary air inlet and the center P of the rack assembly is W1.

[0010] In some embodiments, the W value is not less than 300 mm and not greater than 800 mm, and the L value is not less than 100 mm and not greater than 500 mm.

[0011] In some embodiments, the W value is not less than 300 mm and not greater than 800 mm, and the L value is not less than 100 mm and not greater than 500 mm.

[0012] In some embodiments, the rack assembly includes a front side plate and a rear side plate, the distance h1 between the main air inlet and the rear side plate is greater than the distance h2 between the auxiliary air inlet and the front side plate.

[0013] In some embodiments, the thickness of the rack assembly is H.

[0014] In some embodiments, the H value is not less than 100 mm and not greater than 500 mm.

[0015] In some embodiments, the H value is not less than 100 mm and not greater than 500 mm.

[0016] In some embodiments, a check valve is further included, the check valve is installed at the air outlet and located at the left side of the center line F of the rack assembly extending in the up-down direction, and the check valve is used to prevent backflow of smoke.

[0017] In some embodiments, the distance between the center line E of the air inlet of the check valve extending in the up-down direction and the center line F of the rack assembly extending in the up-down direction is W2.

[0018] In some embodiments, the H value is not less than 100 mm and not greater than 500 mm.

[0019] In some embodiments, the fan assembly includes a volute and an impeller, the impeller is installed in the volute, and the left side, the right side, and the top side of the volute are in abutment with the inner wall surface of the rack assembly.

[0020] In some embodiments, the fan assembly further includes a mounting bearing, the volute is provided with the main air inlet and the auxiliary air inlet on opposite sides in the front-rear direction, the mounting bearing is fixedly connected with the volute and used to fix the impeller in the volute.

[0021] The suction port on the side where the mounting bearing is installed is the auxiliary suction port, and the suction port on the side away from the mounting bearing is the main suction port.

[0022] In some embodiments, the fan assembly further comprises an oil guiding assembly, the bottom of the volute is provided with a flow guiding hole, the oil guiding assembly is fixed with the volute and communicates with the flow guiding hole, and the oil guiding assembly is used to discharge the oil fume in the volute outward.

[0023] In some embodiments, the oil guiding assembly comprises a flow guiding pipe and a mounting member, the rack assembly comprises a rear side plate, the mounting member connects the volute and the rear side plate, the flow guiding pipe communicates with the flow guiding hole and is supported on the mounting member, and the mounting member is provided with an oil leakage hole at one end close to the rear side plate and is used to guide the oil fume guided out of the flow guiding pipe to the oil leakage hole.

[0024] In some embodiments, the flow guiding hole is arranged at the lowest point of the volute.

[0025] In some embodiments, a smoke collecting assembly is further included, the smoke collecting assembly is arranged below the rack assembly and comprises a smoke collecting cover and a condensing plate, the condensing plate comprises a first plate body and a second plate body connected with each other, and the first plate body and the second plate body are arranged at an angle.

[0026] The first plate body is connected to the front side of the smoke collecting cover and is provided with a first smoke suction port communicating with the oil fume suction port, and the second plate body cooperates with the rear back plate of the smoke collecting cover to define a second smoke suction port communicating with the oil fume suction port, in the front-rear direction of the range hood, the first smoke suction port is located at the front side of the second smoke suction port, and the flow cross-sectional area of the first smoke suction port is smaller than that of the second smoke suction port.

[0027] The range hood based on the embodiments of the present application can significantly increase the suction area and suction volume of the range hood by the combined use of the main suction port and the auxiliary suction port, so as to more effectively absorb the oil fume. The auxiliary suction port is arranged towards the rear side of the rack assembly, so as to further suck in the oil fume diffused to the rear side in the cooking process. Moreover, the range hood generates a certain negative pressure when working to attract the oil fume and air to enter. However, if only one suction port is arranged, the negative pressure in the range hood can be too concentrated, leading to uneven distribution of the air pressure inside the range hood. Such imbalance of the air pressure difference not only affects the suction effect of the oil fume, but also can cause airflow turbulence and vortex phenomenon. The arrangement of the auxiliary suction port can effectively suck in the airflow at the rear side, so as to adjust the front-rear air pressure difference, reduce the airflow turbulence and vortex phenomenon, make the airflow distribution more uniform, and improve the discharge efficiency of the oil fume.

[0028] Further, the volute of the present application can abut against the inner wall surface of the rack assembly. Specifically, the left side of the volute abuts against the inner wall surface of the left side plate, the right side of the volute abuts against the inner wall surface of the right side plate, and the upper side of the volute abuts against the inner wall surface of the top side plate, so that the center O of the air suction port and the center P of the rack assembly do not coincide. On the one hand, the size of the rack assembly can be set smaller to adapt to more kitchen layouts and meet the needs of different users; on the other hand, the close abutment of the volute and the rack assembly enhances the stability of the overall structure and reduces vibration and noise during operation. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor based on the drawings shown.

[0030] Figure 1 A structural schematic diagram of a range hood provided by an embodiment of the present application;

[0031] Figure 2 A structural schematic diagram of a rack assembly and a fan assembly provided by an embodiment of the present application (the front side plate is omitted);

[0032] Figure 3 A sectional view schematic diagram of a rack assembly and a fan assembly provided by an embodiment of the present application;

[0033] Figure 4 A structural schematic diagram of a fan assembly provided by an embodiment of the present application;

[0034] Figure 5 A structural schematic diagram of a fan assembly provided by an embodiment of the present application from another perspective;

[0035] Figure 6 A structural schematic diagram of an oil guide assembly provided by an embodiment of the present application;

[0036] Figure 7 A sectional view schematic diagram of a smoke collecting cover provided by an embodiment of the present application.

[0037] BRIEF DESCRIPTION OF DRAWINGS

[0038] 1. A range hood; 100, a frame assembly; 100a, an oil fume suction port; 100b, a fan cavity; 110, a front side plate; 120, a rear side plate; 130, a top side plate; 200, a fan assembly; 200a, a main air suction port; 200b, an auxiliary air suction port; 200c, an air outlet; 210, a volute; 220, a fan wheel; 230, a mounting bearing; 300, a smoke collection assembly; 300a, a first smoke suction port; 300b, a second smoke suction port; 310, a smoke collection cover; 311, a rear back plate; 320, a condensing plate; 321, a first plate body; 322, a second plate body; 330, a guide plate; 340, an oil collection cup; 400, a check valve; 400a, an air inlet; 500, an oil guide assembly; 510, a guide pipe; 520, a mounting member; 520a, an oil leakage hole.

[0039] The purposes, functional features and advantages of the present application will be further described in conjunction with embodiments, with reference to the accompanying drawings. DETAILED DESCRIPTION

[0040] In order to make the purposes, technical solutions and advantages of the present application clearer, the following will further describe the embodiments of the present application in conjunction with the accompanying drawings.

[0041] The following description relates to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following example embodiments do not represent all embodiments consistent with the present application. Instead, they are merely examples of apparatuses and methods consistent with some aspects of the present application as detailed in the appended claims.

[0042] In the description of the present application, it should be understood that the terms "first", "second" and the like are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance. For those skilled in the art, the specific meaning of the above terms in the present application can be understood in specific cases. In addition, in the description of the present application, unless otherwise specified, "multiple" means two or more. The association between the associated objects is described, which means that there can be three relationships, for example, A and / or B, which means that there are three cases of A alone, A and B together, and B alone. The character " / " generally represents a "or" relationship between the associated objects before and after.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more associated listed items.

[0044] The application provides an oil fume extractor 1 which can be used in a kitchen, and is usually installed near a cooking table plane to better capture oil fume and steam generated by a cooking appliance during cooking.

[0045] Please refer to Figure 1 The oil fume extractor 1 comprises a rack assembly 100, a smoke collection assembly 300 and a fan assembly 200. The smoke collection assembly 300 can be installed below the rack assembly 100, near a cooking area, and mainly functions to collect and guide oil fume generated during cooking. Please refer to Figure 3 The rack assembly 100 has a fan cavity 100b, and the fan assembly 200 is arranged in the fan cavity 100b. The fan assembly 200 generates strong negative pressure suction through rotation, rapidly sucks oil fume collected by the smoke collection assembly 300, and accelerates the oil fume to be discharged outdoors through an air duct, so as to reduce the concentration of oil fume in the kitchen and keep the air in the kitchen fresh.

[0046] Please refer to Figure 3 The rack assembly 100 is provided with an oil fume suction port 100a. Oil fume enters the air duct inside the rack assembly 100 through the oil fume suction port 100a, and continues to flow along the air duct until reaching the fan assembly 200. The rack assembly 100 can have a square shape. This design not only gives the product a neat and elegant appearance, but also maximizes the use of the internal space and facilitates the docking and installation of other components such as the smoke collection assembly 300 and the fan assembly 200. The rack assembly 100 can comprise a front side plate 110, a rear side plate 120, a left side plate, a right side plate, a top side plate 130 and a bottom side plate. These plate members are assembled into an integrated body through welding, bolt connection or other means to form a fan cavity 100b with good sealing performance. The bottom side plate is provided with the oil fume suction port 100a.

[0047] It should be noted that the front side plate 110, the rear side plate 120, the left side plate, the right side plate, the top side plate 130 and the bottom side plate can exist as separate plate members; or according to actual conditions, part of the plate bodies can be designed in an integrated manner to form a cover shell. For example, the rear side plate 120, the left side plate and the right side plate of the application are in an integrated structure, so that the installation of these three plate bodies can be completed at one time, greatly improving the installation efficiency. At the same time, this integrated design also reduces the number of joints between the plate bodies, reduces the risk of oil fume leakage and improves the sealing performance of the product. The above-mentioned plate members can be made of stainless steel or aluminum alloy, which has good heat resistance and corrosion resistance.

[0048] The fan assembly 200 is provided with an air inlet communicating with the oil fume suction port. When the fan assembly 200 is running, the negative pressure suction force generated can suck the external oil fume from the oil fume suction port 100a into the fan cavity 100b, and then enter the inside of the fan assembly 200 through the air inlet, and then be guided to the oil fume exhaust pipe by the airflow generated by the rotation of the fan assembly 200, so as to be discharged outdoors, thereby keeping the kitchen air fresh and the health of the cook. Among them, the air inlet of the embodiment of the present application includes a main air inlet 200a and an auxiliary air inlet 200b, which can significantly increase the air suction area and air suction volume of the range hood, thereby more effectively absorbing oil fume. The main air inlet 200a is arranged towards the rear side of the rack assembly 100, and the auxiliary air inlet 200b is arranged towards the front side of the rack assembly 100.

[0049] The combination of the main air inlet 200a and the auxiliary air inlet 200b can significantly increase the air suction area and air suction volume of the range hood, thereby more effectively absorbing oil fume. The main air inlet 200a is arranged towards the front side of the rack assembly 100, which ensures that it can effectively capture and absorb the oil fume generated during cooking, reducing the possibility of oil fume spreading to other areas of the kitchen.

[0050] The auxiliary air inlet 200b is arranged towards the rear side of the rack assembly 100, which can further suck in the oil fume diffused to the rear side during cooking. Moreover, the range hood 1 will generate a certain negative pressure when working to attract oil fume and air into. However, if only one air inlet is provided, the negative pressure in the range hood 1 may be too concentrated, resulting in uneven distribution of air pressure inside the range hood. This imbalance of air pressure difference not only affects the suction effect of oil fume, but also may cause airflow turbulence and vortex phenomenon. The arrangement of the auxiliary air inlet 200b can effectively suck in the airflow at the rear side, thereby adjusting the front and rear air pressure difference, reducing airflow turbulence and vortex phenomenon, making the airflow distribution more uniform, and improving the exhaust efficiency of oil fume.

[0051] Please refer to Figure 2 and Figure 3, the fan assembly 200 includes a volute 210 and an impeller 220, the volute 210 is provided with the main air inlet 200a and the auxiliary air inlet 200b described above, and is also provided with an air outlet 200c, the center O of the main air inlet 200a and the center O of the auxiliary air inlet 200b do not coincide with the center P of the rack assembly 100. The center of the air inlet of the present application can be the axis of the impeller 220, which is beneficial to reduce the wind resistance of the air suction system and facilitate the convergence of the air inlet to the oil fume. The impeller 220 is installed in the volute 210. In order to make the airflow form an effective airflow profile in the volute 210, the center of the impeller 220 is usually not completely coincident with the center of the volute 210. This design is based on the principle of fluid mechanics. By adjusting the relative position between the impeller 220 and the volute 210, the airflow can be guided to flow along a predetermined path, forming a gradually expanding trend. The gradually expanding airflow profile means that the airflow gradually spreads in the volute 210, reducing the flow velocity of the airflow and increasing its static pressure. Therefore, the impeller 220 naturally has a certain offset in the volute 210, and the present application matches the offset position of the impeller 220 in the volute 210 with the offset position of the rack assembly 100, which is beneficial to the miniaturization design of the rack assembly 100.

[0052] Specifically, the volute 210 of the present application can abut the inner wall surface of the rack assembly 100. The left side of the volute 210 abuts the inner wall surface of the left side plate, the right side of the volute 210 abuts the inner wall surface of the right side plate, and the upper side of the volute 210 abuts the inner wall surface of the top side plate 130. In this way, the length dimension (left-right direction) and the height dimension (up-down direction) of the rack assembly 100 will be correspondingly arranged according to the size of the volute 210, and at this time the axis of the impeller 220 will naturally not coincide with the center P of the rack assembly 100, which not only ensures the airflow profile formed by the impeller 220 in the volute 210 to meet the air volume, but also allows the size of the rack assembly 100 to be smaller. This is particularly useful in situations where kitchen space is limited, and a small and compact range hood 1 can adapt to more kitchen layouts and meet the needs of different users.

[0053] In some embodiments, referring to Figure 2 The impeller 220 is a multi-blade centrifugal impeller 220, the rotation direction is clockwise, and the blades of the multi-blade centrifugal impeller 220 are forward blades. In a multi-blade centrifugal fan or other rotating fluid machinery, a forward blade (also known as a forward-curved blade or a forward-swept blade) refers to the inclination direction of the blade, which makes the leading edge closer to the air inlet of the impeller 220 relative to the rotation direction, and the trailing edge is closer to the air outlet 200c of the impeller 220. In other words, the inclination angle of the forward blade (i.e. the angle between the blade chord and the rotation plane of the blade) allows the blade to "push" or "pull" air to flow forward when rotating, i.e. to accelerate the airflow along the rotation direction of the blade and the outlet direction.

[0054] In the present application, the blades of the multi-wing centrifugal impeller 220 are in the same direction as the rotation direction, which can more effectively introduce and accelerate the gas from the axial direction when the impeller rotates. In this process, as the impeller 220 rotates, the blades exert a tangential force on the gas, causing the gas to gain angular momentum and begin to accelerate along the curvature direction of the blades. The accelerated gas enters the volute 210, which is designed in a shape that gradually decelerates the gas during flow. According to Bernoulli's principle, when the gas speed decreases, its pressure will increase accordingly, i.e. the accelerated gas decelerates in the volute 210 and converts into pressure energy, which helps to increase the air volume and pressure of the fan under the same power. Because the blades are in the same direction as the rotation direction, the flow of gas on the blades is smoother, and vortex and turbulent flow phenomena are effectively suppressed. This not only reduces energy loss, but also enables the fan to output greater air volume and higher air pressure under the same power. Moreover, it can also reduce vortex and turbulent flow phenomena, thereby reducing the noise of the fan assembly 200.

[0055] The center O of the main air inlet 200a and the center O of the auxiliary air inlet 200b are located to the right of the center P of the rack assembly 100; or the center O of the main air inlet 200a and the center O of the auxiliary air inlet 200b are located above the center P of the rack assembly 100; or the center O of the main air inlet 200a and the center O of the auxiliary air inlet 200b are located to the right and above the center P of the rack assembly 100. Since the above-mentioned blades are forward blades and the rotation direction is clockwise, the axis of the impeller 220 in the volute 210 will be biased to the right, and the center O of the main air inlet 200a and the center O of the auxiliary air inlet 200b will be located to the right of the center P of the rack assembly 100.

[0056] Specifically, the left side of the volute 210 abuts against the inner wall surface of the left side plate, the right side of the volute 210 abuts against the inner wall surface of the right side plate, and the top side of the volute 210 abuts against the inner wall surface of the top side plate 130, so that the air inlet center O is arranged to the right of the center P of the rack assembly 100, and the bottom of the volute 210 can leave a certain space for installing other components (such as the oil guiding assembly 500 for guiding the tobacco tar in the volute 210 or other components). In this way, the air inlet center O is located to the right and above the center P of the rack assembly 100. The close abutment of the volute 210 and the rack assembly 100 in the present application enhances the stability of the overall structure, reduces vibration and noise during operation, and allows the size of the rack assembly 100 to be smaller.

[0057] In the present application, due to the specific abutment mode of the volute 210 and the rack assembly 100, the center O of the suction port is naturally arranged on the upper right side of the center P of the rack assembly 100. This layout makes the suction port away from the head of the cook during use, reducing the direct impact of noise and oil fume on the cook. Moreover, through the compact design of the volute 210 and reasonable space utilization, it should be pointed out that the fan assembly 200 generally also includes a mounting bearing 230, which is fixed relative to the volute 210, and then the fan wheel 220 is mounted on the mounting bearing 230. It can be understood that the front and back of the volute 210 will be provided with openings communicating with the inner cavity to form the suction port, and the mounting bearing 230 will be generally mounted on one side of the volute 210 and will block at least part of the area of the suction port on that side, resulting in that among the suction ports on the front and back of the volute 210, the area of one suction port will be relatively large (i.e. the main suction port 200a), and the area of the other suction port will be relatively small (i.e. the auxiliary suction port 200b).

[0058] It can be understood that the range hood 1 will generate a certain negative pressure when working to attract oil fume and air into. However, if only one suction port is provided, the negative pressure in the range hood 1 may be too concentrated, resulting in uneven distribution of air pressure inside the range hood. This imbalance of air pressure difference not only affects the suction effect of oil fume, but also may cause airflow turbulence and vortex phenomenon, thereby generating noise. By providing the main suction port 200a and the auxiliary suction port 200b, the present application can not only increase the air volume, thereby increasing the exhaust efficiency of oil fume, but also adjust the front and back air pressure difference, reduce airflow turbulence and vortex phenomenon, make the airflow distribution more uniform, and reduce the generation of noise.

[0059] Please refer to Figure 3 , the distance h1 between the main suction port 200a and the rear side plate 120 is greater than the distance h2 between the auxiliary suction port 200b and the front side plate 110. Since the main suction port 200a has a larger area, its suction force is also stronger. The larger h1 distance helps to form a more stable airflow field at the main suction port 200a. When oil fume or air is sucked in, the larger distance can reduce the direct collision of airflow with the side plate, thereby reducing the occurrence of vortex and turbulence phenomenon, and the stable airflow field helps to improve the suction efficiency and reduce noise and vibration. Since the area of the auxiliary suction port 200b is smaller than that of the main suction port 200a, the suction force is not as strong as that of the main suction port 200a, and the smaller h2 distance may help to enhance the suction force of the auxiliary suction port 200b. Due to the close distance, the rear side plate 120 can have a certain guiding effect on the airflow passing through the auxiliary suction port 200b, making the airflow more easily sucked in and accelerated through the volute 210.

[0060] Please refer to Figure 3 , the dimension defining the front-rear direction of the rack assembly 100 is H; wherein, The application further provides that the ratio of the air volume sucked in by the main air inlet 200a to the air volume sucked in by the auxiliary air inlet 200b ranges from 9:1 to 7:3. Within this ratio range, the main air inlet 200a serves as the main air inlet, and the larger air volume thereof can ensure the formation of a stable air pressure gradient inside the range hood 1. The auxiliary air inlet 200b, although having a smaller air volume, plays a role in supplementing and balancing the air flow, so that the overall air pressure distribution is more uniform. Uniform air flow distribution can reduce the occurrence of vortex and turbulent flow phenomena. Vortex and turbulent flow not only reduce the suction efficiency, but also increase noise and vibration. Through reasonable air volume distribution, the air flow can flow more smoothly through the volute 210 and the fan wheel 220, reducing unnecessary energy loss. The application defines The ratio of the air volume sucked in by the main air inlet 200a to the air volume sucked in by the auxiliary air inlet 200b can be conveniently controlled to range from 9:1 to 7:3. It should be noted that the air inlet area of the main air inlet 200a is not the same as that of the auxiliary air inlet 200b. Therefore, those skilled in the art can set the specific values of h1, h2 and H according to the air volume ratio of the main air inlet 200a to the auxiliary air inlet 200b and the proportional relationship of h1, h2 and H provided in the application.

[0061] In some embodiments, referring to Figure 2 , the size of the rack assembly 100 in the left-right direction is defined as W, and the size in the up-down direction is defined as L; the vertical distance between the center O of the air inlet and the center P of the rack assembly 100 is defined as L1, and the lateral distance between the center O of the air inlet and the center P of the rack assembly 100 is defined as W1; wherein,

[0062] This ratio limits the offset of the air inlet center O in the width direction of the rack assembly 100; This ratio limits the offset of the air inlet center O in the height direction of the rack assembly 100. Specifically, in the case where the same size volute 210 is used and the inner wall surface of the volute 210 and the inner wall surface of the rack assembly 100 abut each other, if the offset of the air inlet center O and the center P of the rack assembly 100 is too large, the position of the shaft center of the fan wheel 220 in the volute 210 will also be offset accordingly. This offset will change the initial direction and speed of the air flow entering the volute 210, thereby destroying the originally designed air flow profile. The air flow profile refers to the flow path and shape of the air flow in the volute 210. When the air inlet center deviates from the center of the rack assembly 100 (and also deviates in the volute 210), the air flow will form unstable vortex or turbulent flow after entering the volute 210, resulting in air volume loss and increased noise.

[0063] If the distance between the shaft of the fan wheel 220 and the volute 210 is kept unchanged, and the volute 210 is offset as a whole, so that the center of the suction port is greatly offset from the center P of the rack assembly 100, the relative position between the volute 210 and the rack assembly 100 is changed. In this case, the size of the rack assembly 100 needs to be set larger to accommodate the offset fan assembly 200, so that the range hood 1 needs a larger installation space.

[0064] In some embodiments, the bottom of the volute 210 is provided with a flow guide hole, which ensures that the oil fume in the volute 210 can be smoothly discharged and avoid accumulation inside the volute 210. The flow guide hole is usually opened at the lowest point of the volute 210. Based on the principle of gravity, the oil in the oil fume can naturally deposit at the bottom of the volute 210 and then be discharged through the flow guide hole. The above-mentioned oil guide assembly 500 is fixed with the volute 210 and communicates with the flow guide hole, and the oil guide assembly 500 is used to guide the position where the oil fume in the volute 210 is discharged outward.

[0065] Please refer back to Figure 3 and Figure 6 The oil guide assembly 500 includes a flow guide pipe 510 and a mounting member 520, the mounting member 520 connects the volute 210 and the rear side plate 120, the flow guide pipe 510 communicates with the flow guide hole and is supported on the mounting member 520, and the mounting member 520 is provided with an oil leakage hole 520a at one end close to the rear side plate 120 and is used to guide the oil fume discharged by the flow guide pipe 510 to the oil leakage hole 520a. The flow guide pipe 510 is installed at the flow guide hole in the present application, which can guide the oil fume to be discharged along a predetermined path, and the flow guide pipe 510 can also play a certain degree of isolation role to reduce the direct propagation of noise generated when the fan wheel 220 operates. Of course, the flow guide pipe 510 can also be made of a material with sound absorption or sound insulation performance, which can further reduce the propagation of noise.

[0066] In the present application, the above-described and the following-described range hood 1, the size (i.e. length) of the rack assembly 100 in the left-right direction is not less than 300 mm and not greater than 800 mm; the size (i.e. height) of the rack assembly 100 in the up-down direction is not less than 300 mm and not greater than 800 mm; and the size (i.e. thickness) of the rack assembly 100 in the front-rear direction is not less than 100 mm and not greater than 500 mm. The range hood 1 provided in the present application can simultaneously meet the advantages of large air volume, good noise reduction effect and small size, which can more quickly absorb and discharge the oil fume and peculiar smell generated during cooking, ensure the fresh air in the kitchen, and will not produce irritating noise during use, so as to provide a more comfortable and quiet cooking environment for the cook, and is also suitable for kitchens with limited space, such as small-sized houses or apartments.

[0067] Please refer to Figure 2The range hood 1 further comprises a check valve 400, which is installed at the air outlet 200c and located at the left side of the center line of the rack assembly 100 extending in the up-down direction, and is used to prevent the backflow of flue gas. In combination with the above, it is continued to be described that, since the suction port of the present application is inclined to the right side of the rack assembly 100, the air outlet 200c of the fan assembly 200 is inclined to the left side of the rack assembly 100, and then the check valve 400 of the present application is inclined to the left side. The main function of the check valve 400 is to prevent the backflow of flue gas to the system or indoor after the flow stops. When the fan stops working or the flow direction of flue gas changes, the check valve 400 will automatically close to ensure that the flue gas will not backflow.

[0068] The transverse distance between the center line E of the air inlet 400a of the check valve 400 extending in the up-down direction and the center line F of the rack assembly 100 extending in the up-down direction is W2; wherein, In this way, it can be ensured that the airflow from the volute 210 can flow to the check valve 400 along the original airflow direction and then enter the exhaust duct. If Less than 0.1 or greater than 0.5, the airflow will be partially hindered when flowing to the check valve 400, the airflow direction will be changed, and vortex and turbulence will be easily generated, resulting in lower flow efficiency of the airflow and noise. Moreover, if Greater than 0.5 means that the distance between the fan assembly 200 and the center line E of the air inlet 400a of the check valve 400 extending in the up-down direction is greater, the distance of the airflow from the impeller 220 to the check valve 400 is longer, and the flow resistance is easily increased, resulting in slower airflow speed and lower flow efficiency.

[0069] Please refer to Figure 1 and Figure 7 The smoke collecting assembly 300 comprises a smoke collecting hood 310 and a condensing plate 320, the condensing plate 320 comprises a first plate body 321 and a second plate body 322 connected together, and the first plate body 321 and the second plate body 322 are arranged at an angle; wherein, the bottom of the rack assembly 100 is provided with an oil smoke suction port 100a. The first plate body 321 is connected to the front side of the smoke collecting hood 310 and is provided with a first smoke suction port 300a communicating with the oil smoke suction port 100a, and the second plate body 322 cooperates with the back plate 311 of the smoke collecting hood 310 to define a second smoke suction port 300b communicating with the oil smoke suction port 100a. In the front-rear direction of the range hood 1, the first smoke suction port 300a is located at the front side of the second smoke suction port 300b, and the flow cross-sectional area of the first smoke suction port 300a is smaller than that of the second smoke suction port 300b.

[0070] Please refer to Figure 7The first plate body 321 is connected to the front side of the smoke collecting hood 310 and is inclined downward from front to back in the front-back direction. One end of the second plate body 322 is connected to one end of the lowest point of the first plate body 321, and the second plate body 322 is also inclined downward from front to back in the front-back direction. Based on this, the opening height of the second smoke inlet 300b is lower than the opening height of the first smoke inlet 300a, and the flow cross-sectional area of the second smoke inlet 300b is larger than the flow cross-sectional area of the first smoke inlet 300a. That is, the strength of the second smoke inlet 300b for collecting oil fume is greater than the strength of the first smoke inlet 300a for collecting oil fume. Therefore, most of the oil fume generated during cooking is collected by the first smoke inlet 300a into the internal air duct of the rack assembly 100. During cooking, the distance between the second smoke inlet 300b and the user is greater than the distance between the first smoke inlet 300a and the user. The first smoke inlet 300a is generally located above the user's head, and the second smoke inlet 300b is generally located in front of the user. Most of the oil fume is collected before reaching the user's head, reducing direct contact between the oil fume and the user and improving the comfort of cooking. Moreover, the distance between the second smoke inlet 300b and the user is greater, so the noise generated has relatively less impact on the user. Although the first smoke inlet 300a is located near the user's head, the noise generated is relatively small because the suction force is weak and the oil fume captured has already moved away from the source.

[0071] Please refer to Figure 7 The smoke collecting hood 310 is provided with an oil collecting cup 340 and a flow guide plate 330. In the front-back direction of the range hood 1, the flow guide plate 330 is inclined downward from back to front and located in the slot of the oil collecting cup 340. The smoke collecting assembly 300 further includes a mounting bracket fixedly connected to the smoke collecting hood 310, and the flow guide plate 330 is mounted on the mounting bracket. The flow guide plate 330 is used to guide the oil fume to flow along a specific path to improve the efficiency of the oil fume entering the second smoke inlet 300b. At the same time, the oil fume with a higher temperature is likely to form oil droplets when it contacts the flow guide plate 330 with a lower temperature. The oil droplets can smoothly slide into the oil collecting cup 340 under the joint action of gravity and the flow guide plate 330, reducing the accumulation and dripping of oil droplets in the smoke collecting hood 310. The oil collecting cup 340 can be detachably mounted on the hood body, and the user can regularly clean the oil droplets in the oil collecting cup 340 to maintain the cleanliness and high efficiency of the range hood 1.

[0072] The same or similar reference numerals in the drawings of the embodiments correspond to the same or similar components; in the description of the present application, it is understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right" and the like are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationships in the drawings are only used for exemplary illustration, and cannot be understood as a limitation on the present application, for those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0073] The above is only a preferred embodiment of the present application, and is not intended to limit the present application, any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A range hood characterized by, The range hood comprises: a rack assembly provided with an oil fume suction port at the bottom; a fan assembly arranged in the rack assembly, the fan assembly being provided with a main suction port and an auxiliary suction port communicating with the oil fume suction port, and an air outlet communicating with the main suction port and the auxiliary suction port, the main suction port being arranged towards the front side of the rack assembly, the auxiliary suction port being arranged towards the rear side of the rack assembly, and the air outlet being arranged towards the top side of the rack assembly; wherein the centers O of the main suction port and the auxiliary suction port are not coincident with the center P of the rack assembly. The fan assembly comprises a multi-wing centrifugal impeller, the rotation direction of the multi-wing centrifugal impeller being clockwise when viewed from the front of the range hood, and the fan blades of the multi-wing centrifugal impeller being forward blades.

2. The hood as claimed in claim 1, wherein, The centers O of the main suction port and the auxiliary suction port are located at the right side of the center P of the rack assembly.

3. The hood as claimed in claim 2, wherein, The centers O of the main suction port and the auxiliary suction port are located at the upper side of the center P of the rack assembly. The dimensions of the rack assembly in the left-right direction are defined as W, and the dimensions of the rack assembly in the up-down direction are defined as L, the centers O of the main suction port and the auxiliary suction port are located at the upper right side of the center P of the rack assembly, the vertical distance between the centers O of the main suction port and the auxiliary suction port and the center P of the rack assembly is defined as L1, and the horizontal distance between the centers O of the main suction port and the auxiliary suction port and the center P of the rack assembly is defined as W1.

4. The hood as claimed in claim 3, wherein, The value of W is not less than 300 mm and not more than 800 mm, and the value of L is not less than 100 mm and not more than 500 mm. wherein 5. The hood as claimed in claim 4, wherein, The rack assembly comprises a front side plate and a rear side plate, the distance h1 between the main suction port and the front side plate is greater than the distance h2 between the auxiliary suction port and the rear side plate.

6. The hood as claimed in claim 2 wherein, The thickness of the rack assembly is defined as H.

7. The hood according to claim 6, characterized in that The value of H is not less than 100 mm and not more than 500 mm. wherein 8. The hood according to claim 7, characterized in that A check valve is further arranged at the air outlet and located at the left side of the center line F of the rack assembly extending in the up-down direction, the check valve being used to prevent the backflow of oil fume.

9. The hood according to claim 2, wherein The distance between the center line E of the air inlet of the check valve extending in the up-down direction and the center line F of the rack assembly extending in the up-down direction is W2.

10. The hood according to claim 9, characterized in that The fan assembly comprises a volute and an impeller, the impeller being arranged in the volute, and the left side, the right side and the top side of the volute all abut the inner wall surface of the rack assembly. wherein 11. The hood as claimed in claim 2 wherein, The fan assembly further comprises a mounting bearing, the volute is provided with the main suction port and the auxiliary suction port at the opposite sides in the front-rear direction respectively, the mounting bearing is fixedly connected with the volute and is used to fix the impeller in the volute; 12. The hood according to claim 11, characterized in that wherein the suction port of the side where the mounting bearing is arranged is the auxiliary suction port, and the suction port of the side away from the mounting bearing is the main suction port. The fan assembly further comprises an oil guiding assembly, the bottom of the volute is provided with a flow guiding hole, the oil guiding assembly is fixed with the volute and communicates with the flow guiding hole, and the oil guiding assembly is used to discharge the oil fume in the volute outward.

13. The hood according to claim 11, wherein ​ 14. The hood according to claim 13, characterized in that The oil guide assembly comprises a guide pipe and a mounting member, the rack assembly comprises a rear side plate, the mounting member connects the volute and the rear side plate, the guide pipe communicates with the guide hole and is supported on the mounting member, and an oil leakage hole is arranged at one end of the mounting member close to the rear side plate and used for guiding the tobacco oil guided out of the guide pipe to the oil leakage hole.

15. The hood according to claim 13, wherein The guide hole is arranged at the lowest point of the volute.

16. The hood according to claim 2, wherein The smoke collection assembly is arranged below the rack assembly and comprises a smoke collection cover and a condensing plate, the condensing plate comprises a first plate body and a second plate body connected with each other, and the first plate body and the second plate body are arranged at an angle. The first plate body is connected to the front side of the smoke collection cover and is provided with a first smoke suction port communicating with the oil smoke suction port, the second plate body cooperates with the rear back plate of the smoke collection cover to define a second smoke suction port communicating with the oil smoke suction port, in the front-rear direction of the range hood, the first smoke suction port is located at the front side of the second smoke suction port, and the flow cross-sectional area of the first smoke suction port is smaller than the flow cross-sectional area of the second smoke suction port.

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