Fan and air treatment device

Abstract

The utility model relates to the technical field of air treatment, and discloses a fan and an air treatment device. The fan comprises a volute provided with an air inlet and an air outlet, and a volute tongue is constructed in the volute; the impeller is rotationally arranged in the volute; the backflow baffles are arranged in the volute, arranged on the side, facing the air outlet, of the impeller at intervals and used for preventing airflow of the air outlet from flowing back; one end of the backflow baffle is attached to the volute tongue and extends in the direction away from the air outlet. The backflow baffle is arranged in the volute and can prevent airflow of the air outlet from flowing back to the impeller, the pressure of the air outlet is increased, the exhaust air volume is increased, airflow backflow is reduced, the exhaust air volume is increased, and noise of the fan is reduced.

Description

Technical Field

[0001] This application relates to the field of air handling technology, such as a fan and an air handling device. Background Technology

[0002] Currently, with the increasing airtightness of buildings in the industry, people are living indoors for extended periods, resulting in more and more indoor pollutants, including formaldehyde, CO2, odors, and dust.

[0003] Related technologies include devices with fresh air functions that can provide fresh air by introducing outdoor air into the room through a fan, or by introducing stale indoor air into the room through a fresh air duct, thereby improving indoor air quality.

[0004] In the process of implementing the embodiments of this disclosure, at least the following problems were found in the related art:

[0005] In related technologies, because the fan outlet is connected to the fresh air duct, the high resistance of the fresh air duct causes excessively high airflow pressure at the outlet, making exhaust difficult. This results in backflow airflow in the gap between the fan and the side volute, causing reduced airflow, turbulent airflow, and high noise.

[0006] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this application, and therefore may include information that does not constitute prior art known to those skilled in the art. Utility Model Content

[0007] To provide a basic understanding of some aspects of the disclosed embodiments, a brief summary is given below. This summary is not intended as a general commentary, nor is it intended to identify key / important components or describe the scope of protection of these embodiments, but rather as a prelude to the detailed description that follows.

[0008] This disclosure provides a fan and an air handling device to reduce backflow, increase air volume, reduce airflow turbulence, and reduce noise levels.

[0009] This disclosure provides a fan, which includes: a volute having an air inlet and an air outlet, and a volute tongue being constructed inside the volute; an impeller rotatably disposed inside the volute; and a return baffle disposed inside the volute, spaced apart on the side of the impeller facing the air outlet, for preventing airflow from the air outlet from flowing back; wherein one end of the return baffle is abutting against the volute tongue and extends in a direction away from the air outlet.

[0010] Optionally, the wall surface of the return baffle facing the impeller extends in an arc shape, and the wall surface of the return baffle facing the impeller matches the impeller.

[0011] Optionally, there are multiple reflux baffles, with two of the multiple reflux baffles located at opposite ends of the volute tongue.

[0012] Optionally, the return flow baffle includes a mounting surface and a windward surface and a return flow surface disposed at both ends of the mounting surface. The mounting surface is connected to the inner wall surface of the volute. The windward surface faces the impeller, and the return flow surface faces away from the impeller. The distance between the windward surface and the return flow surface gradually decreases along the direction away from the mounting surface.

[0013] Optionally, the windward and return surfaces gradually converge in a linear or non-linear manner along the direction away from the mounting surface, and form a closed connection at the ends of the windward and return surfaces away from the mounting surface.

[0014] Optionally, the cross-sectional area of ​​the return baffle gradually decreases in a linear or non-linear manner along the direction away from the volute tongue; and / or, the ends of the windward and return surfaces away from the volute tongue form a closed connection.

[0015] Optionally, the volute defines a connected fan cavity and an air outlet cavity. The impeller is located inside the fan cavity, and the air outlet cavity has an air outlet. The air outlet cavity includes a first cavity wall and a second cavity wall arranged opposite to each other. The first cavity wall is provided with a volute tongue, and one end of the return baffle is attached to the volute tongue. The distance between the return surface of the return baffle and the second cavity wall is greater than the distance between the windward surface of the return baffle and the outer edge of the impeller.

[0016] Optionally, the distance between the return surface of the return baffle and the second cavity wall is greater than half the distance between the second cavity wall and the impeller.

[0017] Optionally, along the thickness direction of the fan, the height of a return air baffle is greater than or equal to 1 / 5 of the width of the air outlet and less than or equal to 1 / 3 of the width of the air outlet; and / or, the impeller includes a plurality of fan blades spaced apart circumferentially, and the fan further includes: a return air baffle connected to the air inlet side of the plurality of fan blades and disposed near the outer edge of the fan blades, and extending in a ring shape along the circumference of the impeller; wherein, along the radial direction of the impeller, the length of the return air baffle is less than the length of the fan blades, and the outer edge of the return air baffle does not protrude beyond the outer edge of the fan blades.

[0018] This disclosure also provides an air handling device, which includes a fan as described in any of the above embodiments.

[0019] The fan and air handling device provided in this disclosure can achieve the following technical effects:

[0020] In this embodiment of the fan, a backflow baffle is provided inside the volute. The backflow baffle can prevent the airflow from the outlet from flowing back to the impeller, thereby increasing the outlet pressure, increasing the exhaust air volume, reducing airflow backflow, increasing exhaust volume, and reducing fan noise. Furthermore, the backflow baffle is in close contact with the volute tongue, which can prevent airflow from flowing back through the gap between the volute tongue and the backflow baffle, thus improving the backflow prevention effect.

[0021] The above general description and the description below are exemplary and illustrative only and are not intended to limit this application. Attached Figure Description

[0022] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations and drawings do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are shown as similar elements. The drawings are not to be scaled. And wherein:

[0023] Figure 1 This is a schematic diagram of the structure of a fan provided in an embodiment of this disclosure;

[0024] Figure 2 This is a schematic diagram of the structure of an impeller from one perspective, provided in an embodiment of this disclosure;

[0025] Figure 3 This is a structural schematic diagram of an impeller from another perspective, provided in an embodiment of this disclosure;

[0026] Figure 4 This is a partial structural schematic diagram of a fan provided in an embodiment of this disclosure;

[0027] Figure 5 This is a partial structural schematic diagram of another fan provided in an embodiment of this disclosure;

[0028] Figure 6 This is a partial structural schematic diagram of a volute provided in an embodiment of this disclosure;

[0029] Figure 7 This is a structural schematic diagram of a fan provided in an embodiment of the present disclosure from another perspective;

[0030] Figure 8 This is a partial structural schematic diagram of another fan provided in an embodiment of this disclosure;

[0031] Figure 9 This is a partial structural schematic diagram of an air handling device provided in an embodiment of this disclosure;

[0032] Figure 10 This is a partial structural schematic diagram of another air handling device provided in an embodiment of this disclosure;

[0033] Figure 11 This is a partial structural schematic diagram of another air handling device provided in an embodiment of this disclosure;

[0034] Figure 12 This is a partial structural schematic diagram of another air handling device provided in an embodiment of this disclosure;

[0035] Figure 13This is a partial structural schematic diagram of another air handling device provided in an embodiment of this disclosure;

[0036] Figure 14 This is a schematic diagram of the structure of an air handling device provided in an embodiment of this disclosure.

[0037] Figure label:

[0038] 10. Shell; 101. Fresh air inlet; 102. First indoor outlet; 103. First stale air inlet; 104. Second indoor outlet; 105. Stale air outlet; 20. Volute; 21. Impeller; 22. Return air baffle; 23. Fixing plate; 24. Fan blade; 25. Return flow baffle; 251. Windward side; 252. Return flow side; 26. Volute tongue; 27. Air outlet cavity; 271. Air outlet; 28. Fan cavity; 29. ​​Air inlet; 201. First impeller ; 202, Second impeller; 203, First purification device; 204, Second purification device; 205, Fan motor; 206, Partition plate; 207, First cover plate; 208, Second cover plate; 30, Anti-backflow plate; 40, Inner purification plate; 50, Air duct switching plate; 501, Second air outlet housing; 502, Third air outlet housing; 503, Conversion housing; 60, Outer shell; 601, Heat exchange air inlet; 701, Fresh air inlet duct; 702, Fresh air outlet duct. Detailed Implementation

[0039] To provide a more detailed understanding of the features and technical content of the embodiments of this disclosure, the implementation of the embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for illustrative purposes only and are not intended to limit the embodiments of this disclosure. In the following technical description, for ease of explanation, several details are used to provide a full understanding of the disclosed embodiments. However, one or more embodiments may still be implemented without these details. In other cases, well-known structures and devices may be simplified in their depiction to simplify the drawings.

[0040] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this disclosure are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for describing embodiments of this disclosure herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0041] In this disclosure, the terms "upper," "lower," "inner," "middle," "outer," "front," and "rear," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for better description of the embodiments of this disclosure and their implementations, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to require them to be constructed and operated in a specific orientation. Furthermore, some of the aforementioned terms may be used to indicate other meanings besides orientation or positional relationship; for example, the term "upper" may in some cases indicate a dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in the embodiments of this disclosure according to the specific circumstances.

[0042] Furthermore, the terms "set up," "connect," and "fix" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this disclosure according to the specific circumstances.

[0043] Unless otherwise stated, the term "multiple" means two or more.

[0044] The term "and / or" describes an association between objects, indicating that three relationships can exist. For example, A and / or B means: A or B, or A and B.

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in the present disclosure can be combined with each other.

[0046] In related technologies, the fan casing can be divided into a high-pressure side and a low-pressure side according to the air pressure. The high-pressure side is usually located near the air outlet of the centrifugal fan, while the low-pressure side is usually located near the air inlet of the centrifugal fan. During the operation of the fan, the airflow on the high-pressure side will flow to the airflow on the low-pressure side, causing airflow backflow, which makes the airflow turbulent, thereby affecting the fan's exhaust volume and increasing the fan noise.

[0047] Combination Figures 1 to 14 As shown, this disclosure provides a fan, such as... Figures 1 to 3As shown, the fan includes a volute 20 and an impeller 21. The volute 20 has an air inlet 29 and an air outlet 271. The impeller 21 is rotatably disposed inside the volute 20 and includes a plurality of fan blades 24 spaced apart circumferentially. A return air baffle 22 is connected to the air inlet side of the plurality of fan blades 24 and extends in a ring along the circumference of the impeller 21. The length of the return air baffle 22 is less than the length of the fan blades 24 along the radial direction of the impeller 21, and the outer edge of the return air baffle 22 does not protrude beyond the outer edge of the fan blades 24.

[0048] In this embodiment, the impeller 21 rotates within the volute 20, driving airflow from the inlet 29 into the volute 20 and out through the outlet 271. The return air baffle 22 prevents airflow from flowing back from the high-pressure area to the low-pressure area within the volute 20, reducing airflow backflow and effectively minimizing backflow on the inlet side, thus reducing turbulence losses and improving the overall aerodynamic performance of the fan. It also increases fan pressure, increases exhaust volume, and reduces noise. The presence of the return air baffle 22 guides airflow more evenly into the fan blades 24, reducing local pressure fluctuations and further enhancing the fan's operational stability and noise control. Furthermore, the outer edge of the return air baffle 22 does not protrude beyond the outer edge of the fan blades 24, ensuring the connection strength of the multiple fan blades 24 of the impeller 21 while increasing the outer diameter of the impeller 21 and the size of the fan blades 24, thereby increasing the outer diameter of the impeller 21 and improving airflow.

[0049] In addition, when the fan is used in a fresh air system, the high-pressure fan of this embodiment can overcome the strong wind resistance in the exhaust pipe, increase the exhaust air volume, and transport indoor pollutants such as formaldehyde, CO2, odors, and dust to the outside, making the indoor air cleaner.

[0050] Optionally, the outer edge of the return air baffle 22 is flush with the outer edge of the fan blade 24.

[0051] In this embodiment, the outer edge of the return air baffle 22 is flush with the outer edge of the fan blade 24, ensuring a smooth transition of airflow as it enters the fan blade 24 and reducing the possibility of airflow separation and vortex generation. This structure not only effectively reduces the fan's energy loss but also improves the concentration and directionality of the airflow, thereby enhancing the fan's output efficiency and pressure stability. Furthermore, the flush design between the return air baffle 22 and the outer edge of the fan blade 24 reduces fan operating noise and improves overall quietness. While ensuring efficient fan operation, the design also maintains structural simplicity and practicality.

[0052] Optionally, along the radial direction of the impeller 21, the ratio of the length of the return air baffle 22 to the length of the fan blade 24 is greater than or equal to 1 / 4 and less than or equal to 1 / 2.

[0053] In this embodiment, the length of the return air baffle 22 is within the aforementioned range, which ensures efficient fan operation while achieving optimal airflow control. Specifically, a length greater than or equal to 1 / 4 of the fan blades effectively blocks airflow recirculation from the intake side, reducing energy loss. Simultaneously, it avoids the situation where a return air baffle 22 longer than 1 / 2 of the fan blades 24 increases wind resistance or hinders smooth airflow entry. This improves the fan's aerodynamic efficiency while ensuring airflow stability and uniformity, thereby optimizing the overall fan performance.

[0054] Optionally, along the radial direction of the impeller 21, the ratio of the length of the return air baffle 22 to the length of the fan blade 24 is greater than or equal to 1 / 3 and less than or equal to 1 / 2.

[0055] In this embodiment, the length of the return air baffle 22 is within the aforementioned range, which significantly improves the aerodynamic performance and operating efficiency of the fan. This design not only enhances the stability of the fan's outlet air pressure and flow rate but also further reduces operating noise, improving the overall quietness. Furthermore, the minimum length of the return air baffle 22 is greater than 1 / 3, thus ensuring high efficiency while also achieving a lightweight and compact structure.

[0056] Optionally, the fan also includes a fixing plate 23, which is located on the side of the plurality of fan blades 24 away from the air inlet 29. The fixing plate 23 is connected to the plurality of fan blades 24 and extends along the circumference of the impeller 21. The outer edge of the fixing plate 23 is located on the side of the outer edge of the fan blades 24 facing the center of the impeller 21.

[0057] In this embodiment, the impeller 21 is located away from the return air baffle 22, and the outer edge of the fixing plate 23 is located radially inside the outer edge of the fan blade 24. This facilitates the manufacturing and production of the impeller 21, as well as its demolding. Furthermore, the fixing plate 23 increases the strength of the impeller 21, reduces vibration and deformation during rotation, thereby improving the fan's operational stability and reliability. The inward retraction of the fixing plate 23 also avoids interference between the fixing plate 23 and the volute 20, reducing noise and frictional losses, and optimizing the overall flow field distribution of the fan.

[0058] Optionally, along the thickness direction of the impeller 21, the inner ring wall of the projection of the return air baffle 22 abuts against the outer ring wall of the projection of the fixed plate 23.

[0059] In this embodiment, the return air baffle 22 and the fixing plate 23 create a continuous and stable airflow channel within the fan, effectively reducing airflow leakage and turbulence on the inlet and outlet sides, enhancing the fan's airtightness, and improving airflow guidance and concentration, thereby significantly improving the fan's output efficiency and pressure stability. Furthermore, the return air baffle and fixing plate 23 can fix the fan blades 24 radially from both sides of the impeller 21's thickness direction, improving the structural strength of the fan blades 24 and enhancing the fan's operational reliability and service life.

[0060] Optionally, the fixing plate 23 is in the shape of a circular piece, and the central part of the fixing plate 23 is recessed to form a motor mounting part, which is used to install the fan motor 205.

[0061] In this embodiment, the fixing plate 23 is in the shape of a circular plate, which can improve the airtightness of the fan, ensure the stability of the airflow, and facilitate the installation of the fan motor 205 so that the fan motor 205 can be connected to the impeller 21 to drive the impeller 21 to rotate.

[0062] Optionally, such as Figure 8 As shown, there are multiple impellers 21, including a first impeller 201 and a second impeller 202. The fan also includes a fan motor 205, which is connected to both the first impeller 201 and the second impeller 202. The first impeller 201 and the second impeller 202 are arranged side by side, and the fan motor 205 is located between the first impeller 201 and the second impeller 202.

[0063] In this embodiment, the first impeller 201 and the second impeller 202 are connected by a fan motor 205, which enables the two impellers 21 to rotate synchronously. This further reduces the space occupied by the fan and fan motor 205, making the structure more compact, easier to integrate with other devices, reducing the occupied area, increasing the versatility of use, and thus improving the user experience.

[0064] Optionally, such as Figure 9 As shown, the volute 20 includes a partition 206, a first cover plate 207, and a second cover plate 208. The partition 206 has a motor cavity, in which a fan motor 205 is located, and the motor shafts at opposite ends of the fan motor 205 extend out of opposite sides of the partition 206. The first cover plate 207 has a first air inlet 29, which covers one side of the partition 206 and encloses a first fan cavity 28 with one end of the partition 206. A first impeller 201 is located in the first fan cavity 28 and is driven connected to one motor shaft of the fan motor 205. The second cover plate 208 has a second air inlet 29, which covers the other side of the partition 206 and encloses a second fan cavity with the other end of the partition 206. A second impeller 202 is located in the second fan cavity and is driven connected to the other motor shaft of the fan motor 205.

[0065] In this embodiment, two impellers 21 are respectively disposed on both sides of the partition plate 206 and covered by a first cover plate 207 and a second cover plate 208. This allows the two impellers 21, the fan motor 205, and the corresponding volutes 20 of the two fans to be connected to form an integrated structure, facilitating installation, movement, and disassembly. It also facilitates the cooperation between the two impellers 21 and one fan motor 205, enabling one fan motor 205 to drive the rotation of both impellers 21.

[0066] Optionally, such as Figures 2 to 7 As shown, the fan also includes a return flow baffle 25, which is disposed inside the volute 20. The return flow baffle 25 is spaced apart on the side of the impeller 21 facing the air outlet 271 to prevent the airflow from the air outlet 271 from flowing back. One end of the return flow baffle 25 is abutted (fitted or close to) the volute tongue 26 and extends away from the air outlet 271.

[0067] The return flow baffle 25 of this embodiment prevents airflow backflow, avoiding backflow within the gap between the volute 20 and the impeller 21. This ensures the fan's output airflow, prevents airflow turbulence, and reduces noise. The presence of the return flow baffle 25 optimizes the flow field distribution inside the volute 20, reducing the generation of eddies and turbulence, further reducing fan energy loss and operating noise. Furthermore, one end of the return flow baffle 25 is in contact with the volute 20, preventing airflow leakage in the volute tongue 26 region, improving the fan's airtightness and operational reliability. The return flow baffle 25 also increases the pressure at the air outlet 271, thereby increasing the fan's exhaust volume.

[0068] In addition, the backflow baffle 25 can improve the sealing of the volute 20, reduce backflow airflow, prevent air leakage, reduce airflow turbulence, and reduce noise.

[0069] Optionally, the wall surface of the return baffle 25 facing the impeller 21 extends in an arc shape, and the wall surface of the return baffle 25 facing the impeller 21 matches the impeller 21.

[0070] In this embodiment, the wall surface of the return baffle 25 facing the impeller 21 is matched with the impeller 21. This allows the wall surface of the return baffle 25 to better conform to the rotation trajectory of the impeller 21, reducing turbulence and energy loss generated in the gap between the return baffle 25 and the impeller 21. This not only improves the smoothness of the airflow but also enhances the airflow guidance effect, making the airflow more concentrated towards the air outlet 271, thereby improving the fan's outlet pressure and flow stability. In addition, the matching design of the arc-shaped wall surface of the return baffle 25 with the impeller 21 reduces the impact of airflow on the return baffle 25, reduces operating noise and vibration, and further improves the fan's quietness and operational reliability.

[0071] Optionally, there may be multiple reflux baffles 25, with two of the multiple reflux baffles 25 located at opposite ends of the volute 20 of the volute tongue 26.

[0072] In this embodiment, return flow baffles 25 are provided at both ends of the volute tongue 26. This prevents airflow backflow from both ends of the volute tongue 26, reducing airflow leakage and loss, and ensuring normal airflow output from the fan. Furthermore, the cooperation between the two return flow baffles 25 and the volute tongue 26 increases the structural strength inside the volute housing 20, improving the overall operational reliability of the fan.

[0073] Optionally, the return baffle 25 includes a mounting surface and a windward surface 251 and a return surface 252 disposed at both ends of the mounting surface. The mounting surface is connected to the inner wall surface of the volute 20. The windward surface 251 faces the impeller 21, and the return surface 252 faces away from the impeller 21. The distance between the windward surface 251 and the return surface 252 gradually decreases along the direction away from the mounting surface.

[0074] In this embodiment, the mounting surface is tightly connected to the inner wall of the volute 20, ensuring the stability of the baffle and the overall structure. The windward surface 251 faces the impeller 21, effectively guiding airflow, reducing turbulence and energy loss, thereby improving airflow efficiency. The return surface 252 faces away from the impeller 21, and the distance between it and the windward surface 251 gradually decreases in the direction away from the mounting surface. This tapering design helps to form a smooth airflow channel, further reducing airflow resistance, preventing airflow backflow, and improving the overall performance of the fan. In addition, the structure of the return baffle 25 can also effectively reduce noise and vibration, extending the service life of the fan.

[0075] Optionally, the cross-sectional area of ​​the return baffle 25 gradually decreases in a linear or non-linear manner along the direction away from the volute tongue 26.

[0076] In this embodiment, the length of the return baffle 25 gradually tapers away from the volute tongue 26. This optimizes the airflow performance within the volute 20. As the airflow passes through the return baffle 25, it is gradually compressed and accelerated, reducing turbulence and flow losses, improving airflow efficiency, reducing airflow resistance, preventing backflow or eddies, and ensuring airflow stability and continuity. The gradually decreasing cross-sectional area of ​​the return baffle 25 helps to evenly distribute airflow pressure, reduce local high-pressure areas, and lower noise and vibration.

[0077] Optionally, the windward side 251 and the return side 252 form a closed connection away from the ends of the volute tongue 26.

[0078] In this embodiment, the windward surface 251 and the return surface 252, which are opposite to the ends of the volute tongue 26, form a closed connection to create a complete airflow channel, preventing airflow leakage or backflow, ensuring the unidirectional and continuous flow of airflow, thereby improving the operating efficiency of the system.

[0079] Optionally, the volute 20 defines a connected fan chamber 28 and an air outlet chamber 27. The impeller 21 is located inside the fan chamber 28. The air outlet chamber 27 has an air outlet 271. The air outlet chamber 27 includes a first chamber wall and a second chamber wall arranged opposite to each other. The first chamber wall is provided with a volute tongue 26. One end of the return baffle 25 is in contact with the volute tongue 26. The distance between the return surface 252 of the return baffle 25 and the second chamber wall is greater than the distance between the windward surface 251 of the return baffle 25 and the outer edge of the impeller 21.

[0080] In this embodiment, the impeller 21 is located within the fan cavity 28 and is responsible for driving the airflow out of the outlet 271. The outlet cavity 27 then directs the airflow through the outlet 271. The first cavity wall of the outlet cavity 27 is provided with a volute tongue 26, and one end of the return baffle 25 is in close contact with the volute tongue 26, ensuring structural stability and airflow continuity. The return baffle 25 forms a gradually expanding airflow channel because the distance between its return surface 252 and the second cavity wall is greater than the distance between its windward surface 251 and the outer edge of the impeller 21. This structure effectively reduces turbulence and energy loss in the outlet cavity 27, while preventing airflow backflow and improving system operating efficiency. Furthermore, the larger distance between the return surface 252 and the second cavity wall helps to evenly distribute airflow pressure, reduce local high-pressure areas, and decrease noise and vibration.

[0081] Optionally, the distance between the return surface 252 of the return baffle 25 and the second cavity wall is greater than half the distance between the second cavity wall and the impeller 21. This ensures an unobstructed airflow path, guarantees air volume, reduces airflow resistance, and maintains overall efficiency.

[0082] Optionally, along the thickness direction of the fan, the height of a return baffle 25 is greater than or equal to 1 / 5 of the width of the air outlet 271, and less than or equal to 1 / 3 of the width of the air outlet 271.

[0083] In this embodiment, the height of the return baffle 25 is within this range, which can significantly improve the airflow control effect of the return baffle 25. The appropriate height ensures that the return baffle 25 can effectively guide the airflow, reduce turbulence and energy loss, and avoid causing excessive resistance to the airflow. A height greater than 1 / 5 of the width of the air outlet 271 allows the return baffle 25 to fully intercept and guide the airflow, prevent backflow, and improve the operating efficiency of the fan; while a height less than or equal to 1 / 3 of the width of the air outlet 271 avoids excessive obstruction of the airflow by the return baffle 25, ensuring smooth airflow and reducing pressure loss.

[0084] Optionally, along the thickness direction of the fan, the height of a return flow baffle 25 is greater than or equal to 1 / 4 of the width of the air outlet 271, and less than or equal to 1 / 3 of the width of the air outlet 271. This can improve the effect of the return flow baffle 25 in blocking backflow.

[0085] This disclosure also provides an air handling apparatus, which includes a fan as described in any of the preceding embodiments.

[0086] The air handling apparatus of this disclosure includes the fan of any of the above embodiments, and therefore has the beneficial effects of the fan of any of the above embodiments, which will not be described again here.

[0087] Optionally, such as Figures 9 to 14 As shown, the air handling unit includes a fresh air module, which includes a housing 10, a first fan, and a first purification device 203. The housing 10 defines a first airflow channel having a fresh air inlet 101, a first indoor outlet 102, and a first stale air inlet 103. The first fan is located within the first airflow channel, with its inlet connected to the fresh air inlet 101 and / or the first stale air inlet 103, and its outlet connected to the first indoor outlet 102. The first purification device 203 is located within the first airflow channel and is used to purify the airflow flowing into the fresh air inlet 101 and / or the first stale air inlet 103. The fan includes a first impeller 201. Here, the fresh air inlet is connected to the outside, and both the first indoor outlet and the first stale air inlet are connected to the interior.

[0088] In this embodiment, the first fan drives outdoor airflow into the first airflow channel and then into the room through the first indoor outlet 102, providing fresh air to the room. The first fan also drives indoor airflow into the first airflow channel from the first stale air inlet 103, and after purification through the first airflow channel, it flows into the room through the first indoor outlet 102. Thus, the air handling device, by setting up the first airflow channel and the first purification device 203, can effectively distinguish between fresh air and stale indoor air. Fresh air flows in from the fresh air inlet 101, passes through the first airflow channel, and is purified by the first purification device 203 before being sent into the room through the first indoor outlet 102. This provides fresh air to the room while also purifying impurities, ensuring indoor air quality. Stale indoor air flows in from the first stale air inlet 103, is purified by the first purification device 203, and then returns to the room through the first indoor outlet 102. This separation process significantly improves the air purification effect, ensuring continuous optimization of indoor air quality. Furthermore, the first airflow channel can also simultaneously connect with both the fresh air inlet and the first stale air inlet, allowing both fresh air and stale indoor air to flow in at the same time, thus regulating the fresh air temperature.

[0089] The air inlet of the first fan is connected to the fresh air inlet 101 and / or the first stale air inlet 103, allowing the device to flexibly switch between fresh air mode and internal circulation mode according to actual needs. In fresh air mode, the device introduces fresh outdoor air; in internal circulation mode, the device purifies indoor air. This flexible airflow control method can meet the air handling needs of different scenarios. Through reasonable design of airflow channels and fan layout, the air handling unit can effectively reduce energy consumption during operation. At the same time, the first purification device 203 has a long service life, reducing the cost and resource waste of frequent filter replacements, making it more energy-efficient and environmentally friendly.

[0090] Furthermore, the fresh air inlet 101, the first stale air inlet 103, and the first indoor outlet 102 of the casing 10 are integrated into the same airflow channel, resulting in a compact structure that facilitates installation and spatial layout. Moreover, the modular design of the first purification device 203 and the fan facilitates disassembly and maintenance, extending the lifespan of the device.

[0091] Optionally, the first purification device 203 includes a high-efficiency filter. For example, the first purification device 203 includes HEPA filtration, activated carbon adsorption, etc.

[0092] In this embodiment, the first purification device 203 is disposed within the first airflow channel and is used to purify indoor stale air flowing in from the first stale air inlet 103 and / or fresh air flowing in from the fresh air inlet 101. Through multi-layer filtration or high-efficiency purification technology, particulate matter, odors, and harmful substances in the air can be effectively removed, further improving the cleanliness of indoor air.

[0093] Optionally, such as Figure 12 As shown, the air handling unit also includes an anti-backflow plate 30 and an internal purification plate 40. The anti-backflow plate 30 is movably disposed at the fresh air inlet 101 and is used to open or close the fresh air inlet 101. The internal purification plate 40 is movably disposed at the first turbid air inlet 103 and is used to open or close the first turbid air inlet 103. When the anti-backflow plate 30 opens the fresh air inlet 101 and the internal purification plate 40 closes the first turbid air inlet 103, the fresh air flowing into the fresh air inlet 101 is driven by the first fan to flow through the first airflow channel and then out to the room from the first indoor outlet 102. When the anti-backflow plate 30 closes the fresh air inlet 101 and the internal purification plate 40 opens the first turbid air inlet 103, the airflow in the room is driven by the first fan to flow into the first airflow channel from the first turbid air inlet 103 and then out to the room from the first indoor outlet 102 after being purified by the first purification device 203.

[0094] In this embodiment, the anti-backflow plate 30 is movably disposed at the fresh air inlet 101, and can be opened or closed as needed. When the outdoor air quality is poor (such as smog, dust, etc.), the anti-backflow plate 30 closes the fresh air inlet 101, effectively preventing outdoor pollutants from flowing back into the room and ensuring the cleanliness of the indoor air. This design significantly enhances the environmental adaptability of the air handling device, and is particularly suitable for areas with severe pollution. The internal purification plate 40 is movably disposed at the first turbid air inlet 103, and can be opened or closed as needed. When the anti-backflow plate 30 closes the fresh air inlet 101 and the internal purification plate 40 opens the first turbid air inlet 103, the device enters the internal circulation mode. The first fan drives the indoor airflow to flow in from the first turbid air inlet 103, and after being purified by the first purification device 203, it is sent back into the room from the first indoor outlet 102. This mode can efficiently purify indoor air and is suitable for scenarios where the outdoor air quality is poor or where rapid improvement of indoor air quality is required. Through the coordinated operation of the anti-backflow plate 30 and the internal purification plate 40, the air purification device can flexibly switch between fresh air mode and internal circulation mode according to actual needs. In fresh air mode, the anti-backflow plate 30 opens the fresh air inlet 101, and the internal purification plate 40 closes the first stale air inlet 103, allowing the device to introduce fresh outdoor air. In internal circulation mode, the anti-backflow plate 30 closes the fresh air inlet 101, and the internal purification plate 40 opens the first stale air inlet 103, allowing the device to circulate and purify indoor air. This flexible mode switching function can meet the air treatment needs in different scenarios and improve the user experience.

[0095] Furthermore, the design of the anti-backflow plate 30 and the internal purification plate 40 enables the air purification device to automatically select the optimal operating mode based on indoor and outdoor air quality, avoiding unnecessary energy consumption. For example, when outdoor air quality is good, the fresh air mode is used first; when outdoor air quality is poor, it automatically switches to the internal circulation mode to reduce the introduction of outdoor pollutants and lower energy consumption. Moreover, the anti-backflow plate 30 and the internal purification plate 40 adopt a movable design, with a simple structure and easy automation control. Through motor drive or manual adjustment, the opening and closing states of the fresh air inlet 101 and the first stale air inlet 103 can be quickly and accurately controlled, ensuring the efficient operation of the air handling device. By adding the anti-backflow plate 30 and the internal purification plate 40, the air handling device of this invention not only possesses the functions of anti-backflow and internal circulation purification, but also achieves flexible airflow mode switching and energy-efficient operation, significantly improving the device's practicality, environmental adaptability, and user experience.

[0096] Optionally, such as Figures 9 to 12As shown, the housing 10 also defines a second airflow channel with a second turbid air inlet and a turbid air outlet 105. The turbid air outlet 105 is connected to the outside. The fan also includes a second fan, which includes a second impeller 202. The second fan is located within the receiving cavity and is connected between the second turbid air inlet and the turbid air outlet 105. The second fan can drive the indoor airflow to flow from the second turbid air inlet into the second airflow channel and then out of the turbid air outlet 105. Here, the second turbid air inlet is connected to the indoor environment, and the turbid air outlet 105 is connected to the outside environment.

[0097] In this embodiment, the second airflow channel is used to treat indoor stale air. The second fan drives the indoor stale air to flow into the second airflow channel through the second stale air inlet, and then exhausts it to the outside through the stale air outlet 105, thus achieving indoor exhaust. This independent airflow channel design avoids the mixing of stale air and fresh air, ensuring the cleanliness of indoor air while reducing pollution to the outdoor environment. Through the stale air exhaust function of the second airflow channel, the device can quickly exhaust indoor stale air, preventing pollutants from accumulating indoors. By setting up the second airflow channel and the second fan, the air handling capacity of the air handling device is further enhanced. Fresh air flows into the room through the first airflow channel to supplement fresh air, and the second airflow channel can exhaust stale air to the outside, thereby improving indoor and outdoor air circulation and rapidly improving indoor air quality. When circulating within the first airflow channel, the airflow flowing in through the first stale air inlet 103 passes through the first purification device 203 and flows into the room, while the airflow in the second airflow channel can exhaust air to the outside, also improving indoor air quality.

[0098] Optionally, the air handling device further includes a second purification device 204, which is disposed in the second airflow channel and is used to purify the airflow flowing in from the second turbid air inlet. The second fan can drive the indoor airflow to flow into the second airflow channel from the second turbid air inlet and flow out from the turbid air outlet 105 after being purified by the second purification device 204.

[0099] In this embodiment, the second airflow channel is used to treat indoor stale air. The second fan drives the indoor stale air to flow into the second airflow channel through the second stale air inlet, and then, after being purified by the second purification device 204, it is discharged to the outside through the stale air outlet 105, thus achieving indoor exhaust. The purification function of the second purification device 204 further improves the cleanliness of the indoor air, providing users with a healthier and more comfortable air environment. By setting up the second airflow channel, the second fan, and the second purification device 204, the air handling methods of the air handling device are further enhanced. Fresh air flows into the room through the first airflow channel to supplement fresh air, and the second airflow channel can discharge stale air to the outside, thereby improving the indoor and outdoor air circulation and rapidly improving the indoor air quality.

[0100] Optionally, the housing 10 also has a second indoor outlet 104, which is connected to the second airflow channel. The air handling unit also includes a duct switching plate 50, which is movably disposed in the second airflow channel and is used to adjust the connection between the outlet of the second fan and the stale air outlet 105 or the outlet of the second fan and the second indoor outlet 104, so that the airflow driven by the second fan from the second stale air inlet flows from the stale air outlet 105 to the outside or flows into the room through the second indoor outlet 104. Here, the second indoor outlet is connected to the room.

[0101] In this embodiment, the air duct switching plate 50 is movably disposed within the second airflow channel, and can adjust the connection state between the outlet of the second fan and the stale air outlet 105 or the second indoor outlet 104 according to actual needs. When the air duct switching plate 50 connects the outlet of the second fan with the stale air outlet 105, the air handling device enters the stale air discharge mode, purifying the indoor stale air and discharging it outdoors; when the air duct switching plate 50 connects the outlet of the second fan with the second indoor outlet 104, the air handling device enters the internal circulation mode, returning the purified airflow to the room. This flexible mode switching function can meet the air handling needs in different scenarios, improve the practicality of the device, and increase air handling efficiency and energy utilization. Furthermore, through the setting of the air duct switching plate 50, the connection between the outlet of the second fan and the stale air outlet 105 or the second indoor outlet 104 can be flexibly adjusted, achieving controllable adjustment of the airflow direction, thereby improving the flexibility and versatility of air handling and increasing air handling efficiency. Through the design of the air duct switching plate 50, the second airflow channel can not only discharge stale air but also return the purified airflow to the room. This dual-function integration allows the device to achieve both stale air exhaust and internal circulation purification within a single structure, saving space and cost. Furthermore, the air duct switching plate 50 enables the air handling unit to automatically select the optimal operating mode based on indoor and outdoor air quality. For example, when outdoor air quality is poor, the air handling unit can switch to internal circulation mode to prevent the introduction of outdoor pollutants; when indoor air quality is poor, the air handling unit can switch to stale air exhaust mode to quickly expel polluted indoor air. This intelligent operation not only improves air handling efficiency but also reduces energy consumption, making it more energy-efficient and environmentally friendly.

[0102] In one specific embodiment, when the anti-backflow plate 30 opens the fresh air inlet 101, the inner purification plate 40 closes the first turbid air inlet 103, and the air duct switching plate 50 switches to connect the outlet of the second fan with the turbid air outlet 105, the air handling device operates in super ventilation mode. Fresh outdoor air flows into the room through the fresh air inlet 101, the first airflow channel, and the first indoor outlet 102 to replenish the indoor air with fresh air. At the same time, the turbid air in the room flows into the second airflow ventilation duct through the second turbid air inlet and is then discharged to the outside through the turbid air outlet. This enables rapid ventilation and thus rapidly improves the indoor air quality.

[0103] In another specific embodiment, when the anti-backflow plate 30 opens the fresh air inlet 101, the inner purification plate 40 closes the first turbid air inlet 103, and the air duct switching plate 50 switches to connect the outlet of the second fan with the second indoor outlet 104, the air handling unit operates in the fresh oxygen mode. Fresh outdoor air flows into the room through the fresh air inlet 101, the first airflow channel, and the first indoor outlet 102 to replenish the room with fresh air. At the same time, the turbid air in the room flows into the second airflow ventilation duct through the second turbid air inlet and is purified by the second purification device 204. Then it flows into the room from the second indoor outlet 104. In this way, the air handling unit can simultaneously replenish fresh air and purify indoor airflow, thus achieving both fresh air and purification functions.

[0104] In another specific embodiment, when the anti-backflow plate 30 closes the fresh air inlet 101, the inner purification plate 40 opens the first turbid air inlet 103, and the air duct switching plate 50 switches to connect the outlet of the second fan with the turbid air outlet 105, the air handling device operates the rapid deodorization mode. The indoor turbid air flows into the room through the first turbid air inlet 103, the first airflow channel, and the first indoor outlet 102, realizing indoor airflow purification. At the same time, the indoor turbid air flows into the second airflow ventilation duct through the second turbid air inlet and then is discharged to the outside from the turbid air outlet. This can discharge the indoor turbid air, thereby enabling indoor purification and outdoor turbid air discharge to be carried out simultaneously. Through indoor purification and exhaust, indoor odors can be quickly discharged.

[0105] In another specific embodiment, when the anti-backflow plate 30 closes the fresh air inlet 101, the inner purification plate 40 opens the first turbid air inlet 103, and the air duct switching plate 50 switches to connect the outlet of the second fan with the second indoor outlet 104, the air handling device operates in ultra-purification mode. The turbid air in the room flows into the room through the first turbid air inlet 103, the first airflow channel, and the first indoor outlet 102, thereby purifying the indoor airflow. At the same time, the turbid air in the room flows into the second airflow ventilation duct through the second turbid air inlet and then flows into the room from the second indoor outlet 104. In this way, the fan can purify the indoor air at the same time and quickly.

[0106] Optionally, the exhaust air outlet 105 and the second indoor outlet 104 have different air outlet directions in the horizontal plane.

[0107] In this embodiment, the exhaust outlet 105 and the second indoor outlet 104 have different airflow directions in the horizontal plane, which can meet the airflow direction requirements of different spatial layouts and improve the adaptability and practicality of air handling. The air handling device of this embodiment effectively solves the technical problems such as single airflow direction, insufficient switching between exhaust and indoor circulation, and single exhaust direction, significantly improving the flexibility and efficiency of air handling, while meeting the needs of diverse usage scenarios.

[0108] Optionally, housing 10 defines a second fan cavity, with a second fan located within the second fan cavity. Housing 10 includes a second air outlet housing 501 and a third air outlet housing 502. The second air outlet housing 501 defines a first exhaust duct with a turbid air outlet 105, the inlet of which communicates with the outlet of the second fan cavity. The third air outlet housing 502 defines a second exhaust duct with a second indoor outlet 104, the inlet of which communicates with the outlet of the second fan cavity. The duct switching plate 50 is movable to a first position and a second position. When the duct switching plate 50 moves to the first position, it closes the inlet of the second exhaust duct, allowing the outlet of the second fan cavity to communicate with the first exhaust duct. When the duct switching plate 50 moves to the second position, it closes the inlet of the first exhaust duct, allowing the outlet of the second fan cavity to communicate with the second exhaust duct.

[0109] In this embodiment, the second exhaust housing 501 and the third exhaust housing 502 respectively define a first exhaust duct with a turbid air outlet 105 and a second exhaust duct with a second indoor outlet 104. This dual-channel design allows the air handling unit to flexibly select the airflow path according to actual needs, realizing the function of turbid air discharge or internal circulation purification, meeting the air handling needs in different scenarios. Through the intelligent control of the duct switching plate 50, the air handling unit can automatically select the optimal operating mode according to the indoor and outdoor air quality, and the connection between the two exhaust ducts and the second fan can be realized by the movement of one duct switching plate 50.

[0110] Optionally, the housing 10 further includes a conversion housing 503, which defines a conversion cavity that connects the outlet of the second fan cavity with the inlet of the first exhaust duct and the inlet of the second exhaust duct; wherein the duct switching plate 50 is movably disposed within the conversion cavity.

[0111] In this embodiment of the present disclosure, the outlet of the second fan is connected to the first exhaust channel and the second exhaust channel through a conversion cavity. This facilitates the setting of the air duct conversion plate, so that the outlet of the second fan can be connected to the first exhaust channel or the second exhaust channel through a single air duct conversion plate.

[0112] Optionally, the bottom of the conversion chamber is connected to the outlet of the second fan chamber, the top of the conversion chamber is connected to the first exhaust duct, and the side of the conversion chamber is connected to the second exhaust duct; wherein, when the duct switching plate 50 moves to the first position, the duct switching plate 50 blocks the space between the side of the conversion chamber and the inlet of the second exhaust duct; when the duct switching plate 50 moves to the second position, the duct switching plate 50 blocks the space between the top of the conversion chamber and the inlet of the first exhaust duct.

[0113] In this embodiment of the present disclosure, the conversion chamber is connected to the top of the second fan, and the first exhaust duct and the second exhaust duct are respectively connected to the top and side of the conversion chamber. This ensures that the positions of the first exhaust duct and the second exhaust duct do not interfere with each other, and also ensures that the turbid air outlet 105 and the second indoor outlet 104 face different directions, thereby realizing multi-directional air outlet of the air handling device.

[0114] Optionally, the extension direction of the first exhaust duct is opposite to the extension direction of the second exhaust duct.

[0115] In this embodiment, the two exhaust ducts extend in opposite directions, which makes the exhaust directions of the stale air outlet 105 and the second indoor outlet 104 opposite. Thus, the stale air outlet 105 is generally connected to the external fresh air duct and will be close to the wall, while the second indoor outlet 104 faces the room and is opposite to the exhaust direction of the stale air outlet 105. This can ensure the air outlet range and improve the aesthetics of the air handling device.

[0116] Optionally, the air handling unit also includes a housing 60, with the fresh air module located within the housing 60. The air handling unit also includes a heat exchange assembly, comprising a heat exchanger and a heat exchange fan, both located within a receiving cavity. Optionally, the air handling unit is located below the receiving cavity, while the heat exchanger and heat exchange fan are located above it. This integrates the air handling unit into the air conditioner, enabling it to perform both cooling and heating functions, as well as fresh air and air purification, thereby improving the air conditioner's versatility in terms of airflow and usage.

[0117] Optionally, the outer casing 60 also has a heat exchange air inlet 601 and a heat exchange air outlet 271. The outer casing 60 has corresponding ventilation openings for the fresh air inlet 101, the stale air outlet 105, the first stale air inlet 103, the first indoor outlet 102, and the second indoor outlet 104. At least one of the ventilation openings corresponding to the fresh air inlet 101, the stale air outlet 105, the first stale air inlet 103, and the first indoor outlet 102 is located on the side wall of the outer casing 60 in the same direction as the heat exchange air inlet 601. The ventilation opening corresponding to the second indoor outlet 104 is located on the side wall of the outer casing 60 in the same direction as the heat exchange air outlet 271.

[0118] Optionally, the air handling unit also includes a fresh air outlet duct 702, which is connected to a stale air outlet 105. The inner wall of the stale air outlet 105 has an internal thread, and the outer wall of the fresh air outlet duct 702 has an external thread. The fresh air outlet duct 702 is threadedly connected to the stale air outlet 105.

[0119] Optionally, the air handling unit also includes a fresh air inlet duct 701, which is connected to the fresh air inlet 101. The air handling unit also includes a connecting pipe, one end of which is threadedly connected to the fresh air outlet duct 702, and the other end of which is detachably connected to the fresh air inlet 101.

[0120] In this embodiment, the diameter of the fresh air inlet duct 701 is larger than the diameter of the fresh air outlet duct 702. Therefore, the air volume of the fresh air inlet duct 701 is larger. Thus, the fresh air inlet duct 701 is connected to the fresh air inlet 101 through the connecting pipe 703, which can improve the connection stability of the fresh air inlet duct 701 and prevent the fresh air inlet duct 701 from deviating, bending or separating from the fresh air inlet 101 due to airflow.

[0121] Optionally, the air handling unit is a cabinet-type air conditioner. It should be understood that the air conditioner could also be any other type of air conditioner.

[0122] The foregoing description and accompanying drawings fully illustrate embodiments of the present disclosure to enable those skilled in the art to practice them. Other embodiments may include structural and other changes. The embodiments represent only possible variations. Individual components and functions are optional unless explicitly required, and the order of operation may vary. Parts and features of some embodiments may be included or substituted for parts and features of other embodiments. Embodiments of the present disclosure are not limited to the structures described above and shown in the accompanying drawings, and various modifications and changes may be made without departing from its scope. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A fan, characterized in that, include: The volute has an air inlet and an air outlet, and the volute has a volute tongue inside. The impeller rotates within the volute casing; A backflow baffle is installed inside the volute and spaced apart on the side of the impeller facing the air outlet to prevent the airflow from flowing back from the air outlet. One end of the return baffle is attached to the volute tongue and extends away from the air outlet.

2. The fan according to claim 1, characterized in that, The wall surface of the return baffle facing the impeller extends in an arc shape, and the wall surface of the return baffle facing the impeller matches the impeller.

3. The fan according to claim 1, characterized in that, There are multiple reflux baffles, and two of the multiple reflux baffles are located at opposite ends of the volute tongue.

4. The fan according to claim 1, characterized in that, The return flow baffle includes a mounting surface and a windward surface and a return flow surface disposed at both ends of the mounting surface. The mounting surface is connected to the inner wall surface of the volute. The windward surface faces the impeller, and the return flow surface faces away from the impeller. The distance between the windward surface and the return flow surface gradually decreases along the direction away from the mounting surface.

5. The fan according to claim 4, characterized in that, Along the direction away from the mounting surface, the windward and return surfaces gradually converge in a linear or nonlinear manner, forming a closed connection at the ends of the windward and return surfaces away from the mounting surface.

6. The fan according to claim 1, characterized in that, Along the direction away from the volute tongue, the cross-sectional area of ​​the return baffle gradually decreases in a linear or non-linear manner; and / or, The windward and return surfaces form a closed connection away from the ends of the volute tongue.

7. The fan according to claim 4, characterized in that, The volute defines a connected fan chamber and an air outlet chamber. The impeller is located inside the fan chamber. The air outlet chamber has an air outlet and includes a first chamber wall and a second chamber wall arranged opposite to each other. The first chamber wall has a volute tongue. One end of the return baffle is attached to the volute tongue. The distance between the return surface of the return baffle and the second chamber wall is greater than the distance between the windward surface of the return baffle and the outer edge of the impeller.

8. The fan according to claim 7, characterized in that, The distance between the return surface of the return baffle and the second cavity wall is greater than half the distance between the second cavity wall and the impeller.

9. The fan according to any one of claims 1 to 8, characterized in that, Along the thickness direction of the fan, the height of a return baffle is greater than or equal to 1 / 5 of the outlet width and less than or equal to 1 / 3 of the outlet width; and / or, The impeller includes multiple blades spaced circumferentially, and the fan also includes: The return air baffle is connected to the air inlet side of multiple fan blades and is set near the outer edge of the fan blades, and extends in a ring along the circumference of the impeller; Along the radial direction of the impeller, the length of the return air baffle is less than the length of the fan blade, and the outer edge of the return air baffle does not protrude beyond the outer edge of the fan blade.

10. An air handling device, characterized in that, Includes the fan as described in any one of claims 1 to 9.

Images