Centrifugal fan and air conditioning device with same

Abstract

The utility model provides a centrifugal fan and an air conditioning device with the same. The centrifugal fan comprises a volute provided with an air inlet, an air outlet, a first through hole and an air duct, the air inlet is communicated with the air outlet through the air duct, and the first through hole is communicated with the air duct; the first through hole is arranged close to a volute tongue of the volute; the shielding structure is movably arranged at the first through hole so as to shield or avoid at least part of the first through hole; and when the shielding structure avoids the first through hole, the first through hole communicates with the environment where the air duct and the centrifugal fan are located. The centrifugal fan effectively solves the problem that in the prior art, large noise is generated in the operation process of a centrifugal fan, and the use experience of a user is affected.

Description

Technical Field

[0001] The utility model relates to the technical field of air-conditioning devices, and in particular, to a centrifugal fan and an air-conditioning device having the same. Background Art

[0002] Currently, there are usually three types of fans in household air conditioners: the cross-flow fan of the indoor unit of the air conditioner, the axial-flow fan of the outdoor unit of the air conditioner, and the centrifugal fan of the fresh air system. Among them, the axial-flow fan is outdoors, and the cross-flow fan and the centrifugal fan are both indoors. Therefore, the cross-flow fan and the centrifugal fan have an important impact on indoor comfort. Since the cross-flow fan is larger in volume than the centrifugal fan, and the inlets and outlets of the cross-flow fan are much larger than those of the centrifugal fan, the cross-flow fan can obtain a larger air volume and heat exchange capacity at a lower rotational speed during operation; while the centrifugal fan needs a higher rotational speed to meet a certain fresh air volume. Therefore, whether evaluated from the fan structure and rotational speed requirements, the noise of the centrifugal fan has always been the main factor affecting indoor noise comfort.

[0003] In the prior art, the noise of the centrifugal fan is usually reduced by reducing the rotational speed of the impeller of the centrifugal fan. However, the above method will result in insufficient supply of fresh air indoors, affecting the user experience. Summary of the Utility Model

[0004] The main purpose of the present utility model is to provide a centrifugal fan and an air-conditioning device having the same, so as to solve the problem that the centrifugal fan in the prior art generates relatively large noise during operation, affecting the user experience.

[0005] To achieve the above object, according to one aspect of the present utility model, there is provided a centrifugal fan, including: a volute having an air inlet, an air outlet, a first through hole, and an air duct, the air inlet is communicated with the air outlet through the air duct, and the first through hole is communicated with the air duct; the first through hole is disposed close to the volute tongue of the volute; a shielding structure, the shielding structure is movably disposed at the first through hole to shield or avoid at least a part of the first through hole; wherein, when the shielding structure avoids the first through hole, the first through hole is communicated with both the air duct and the environment where the centrifugal fan is located.

[0006] Furthermore, the diameter of the first through hole is greater than or equal to 1 mm and less than or equal to 10 mm.

[0007] Furthermore, the centrifugal fan also includes an impeller, and the volute includes: a first cover plate, having a second through hole; a volute body, including an arc-shaped side plate and a volute tongue, the first through hole is arranged on the arc-shaped side plate, and the first cover plate is covered on one side of the volute body; a second cover plate is covered on the other side of the volute body and has a third through hole; wherein the first cover plate, the volute body and the second cover plate are surrounded to form an air duct, the second through hole and the third through hole form an air inlet, and the impeller is arranged in the air duct; the opening rate of the first through hole on the volute body is greater than or equal to 1% and less than or equal to 50%.

[0008] Furthermore, there are a plurality of first through holes, and the plurality of first through holes are arranged at intervals along the thickness direction of the volute body and / or the circumferential direction of the arc-shaped side plate.

[0009] Furthermore, the centrifugal fan also includes: a first driving device; a transmission assembly, the first driving device is drivingly connected to the shielding structure through the transmission assembly to drive the shielding structure to move between the shielding position and the avoidance position.

[0010] Furthermore, the first driving device has a driving shaft, and the transmission assembly includes: a gear structure, which is drivingly connected to the driving shaft; a rack structure, which is arranged on the shielding structure, and the rack structure is meshed with the gear structure; the extension direction of the rack structure is consistent with the movement direction of the shielding structure.

[0011] Furthermore, the centrifugal fan also includes: a first matching part, which is arranged on the volute; and a second matching part, which is arranged on the shielding structure; wherein, one of the first matching part and the second matching part is a protrusion, and the other of the first matching part and the second matching part is a recess, and the protrusion extends into the recess to slide along the extension direction of the recess; the extension direction of the recess is consistent with the movement direction of the shielding structure.

[0012] Furthermore, the centrifugal fan further includes: a bracket, which is arranged on the first cover plate, and the first driving device is installed on the volute through the bracket; wherein the bracket is located outside the air duct.

[0013] Further, there is one rack structure; or, there are multiple rack structures, and the multiple rack structures are arranged at intervals along the thickness direction of the volute; and / or, the rack structure is located on the side of the shielding structure away from the first through hole; and / or, the centrifugal fan also includes a limiting structure, and during the movement of the shielding structure, the limiting structure is used to limit and stop the shielding structure.

[0014] According to another aspect of the utility model, an air conditioning device is provided, comprising the above-mentioned centrifugal fan.

[0015] Applying the technical solution of the present utility model, the centrifugal fan includes a volute and a shielding structure. The volute has an air inlet, an air outlet, a first through hole, and an air duct. The air inlet is communicated with the air outlet through the air duct, and the first through hole is communicated with the air duct. The first through hole is arranged near the volute tongue of the volute. The shielding structure is movably arranged at the first through hole to shield or avoid at least part of the first through hole. Wherein, when the shielding structure avoids the first through hole, the first through hole is communicated with both the air duct and the environment where the centrifugal fan is located. In this way, by opening the first through hole near the volute tongue to communicate with the external environment, the air static pressure inside the volute tongue is effectively increased, the air static pressure near the volute tongue is balanced, the "turbulent kinetic energy" is reduced, and thus the aerodynamic noise of the centrifugal fan is effectively weakened from the source, solving the problem that the centrifugal fan in the prior art generates a large amount of noise during operation, which affects the user experience. At the same time, the shielding structure can not only control the on-off state between the first through hole and the outside and the area communicated with the outside at different rotational speeds of the centrifugal fan, thereby adjusting the size of the balanced static pressure area at different impeller rotational speeds and avoiding additional noise and air volume loss; but also cover the first through hole when the centrifugal fan stops running to prevent foreign objects from entering the centrifugal fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings forming a part of this application are used to provide a further understanding of the present utility model. The schematic embodiments of the present utility model and their descriptions are used to explain the present utility model and do not constitute an improper limitation of the present utility model. In the drawings:

[0017] Figure 1 A three-dimensional structural schematic diagram of the shielding structure of the centrifugal fan according to the embodiment of the present utility model when in the shielding position is shown;

[0018] Figure 2 It shows Figure 1 The three-dimensional structural schematic diagram of the centrifugal fan in after removing the shielding structure;

[0019] Figure 3 It shows Figure 1 The side view of the centrifugal fan in ;

[0020] Figure 4 It shows Figure 3 The A-A cross-sectional view of the centrifugal fan in ;

[0021] Figure 5 It shows Figure 4 The B-B cross-sectional view of the centrifugal fan in ;

[0022] Figure 6 It shows Figure 1 The three-dimensional structural schematic diagram of the first cover plate and the volute body of the centrifugal fan in after assembly;

[0023] Figure 7shows Figure 1 Schematic three - dimensional structure diagram after assembly of the first driving device, transmission component and shielding structure of the centrifugal fan in Figure 1 ;

[0024] Figure 8 shows Figure 1 Bottom view of the second cover plate of the centrifugal fan in Figure 1 ;

[0025] Figure 9 Shows the cross - section static pressure contour map of the centrifugal fan in the prior art;

[0026] Figure 10 Shows the cross - section static pressure contour map of the centrifugal fan according to the present utility model;

[0027] Figure 11 Shows the cross - section turbulent kinetic energy contour map of the centrifugal fan in the prior art;

[0028] Figure 12 Shows the cross - section turbulent kinetic energy contour map of the centrifugal fan according to the present utility model;

[0029] Figure 13 Shows the static pressure contour maps of the centrifugal fan in the prior art and the centrifugal fan according to the present utility model at a distance of 1 m from the air outlet.

[0030] Among them, the above - mentioned drawings include the following reference numerals:

[0031] 10, volute; 11, air inlet; 12, air outlet; 13, first through - hole; 14, volute tongue; 15, first cover plate; 16, volute body; 17, second cover plate; 18, reinforcing rib;

[0032] 20, shielding structure;

[0033] 30, first driving device; 31, driving shaft;

[0034] 41, gear structure; 42, rack structure;

[0035] 50, first mating part;

[0036] 60, bracket;

[0037] 70, limiting structure;

[0038] 80, impeller;

[0039] 90, second driving device. Detailed implementation manners

[0040] It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present utility model will be described in detail below with reference to the drawings and in combination with the embodiments.

[0041] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as those commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0042] In the present utility model, unless otherwise stated, the orientation terms such as "upper" and "lower" are usually in reference to the direction shown in the drawings, or in the vertical, perpendicular or gravitational directions; similarly, for the convenience of understanding and description, "left" and "right" are usually in reference to the left and right shown in the drawings; "inner" and "outer" refer to the inner and outer of the contour of each component itself, but the above orientation terms are not used to limit the present utility model.

[0043] In order to solve the problem that the centrifugal fan in the prior art generates relatively large noise during operation, which affects the user experience, the present application provides a centrifugal fan and an air-conditioning device having the same.

[0044] As Figures 1 to 8 shown, the centrifugal fan includes a volute 10 and a shielding structure 20. The volute 10 has an air inlet 11, an air outlet 12, a first through hole 13 and an air duct. The air inlet 11 is communicated with the air outlet 12 through the air duct, and the first through hole 13 is communicated with the air duct; the first through hole 13 is arranged near the volute tongue 14 of the volute 10. The shielding structure 20 is movably arranged at the first through hole 13 to shield or avoid at least part of the first through hole 13. Wherein, when the shielding structure 20 avoids the first through hole 13, the first through hole 13 is communicated with both the air duct and the environment where the centrifugal fan is located.

[0045] Applying the technical solution of this embodiment, by opening the first through hole 13 in the part near the volute tongue 14 to communicate with the external environment, the air static pressure inside the volute tongue is effectively increased, the air static pressure near the volute tongue is balanced, the "turbulent kinetic energy" is reduced, and thus the aerodynamic noise of the centrifugal fan is effectively weakened from the source, solving the problem that the centrifugal fan in the prior art generates relatively large noise during operation, which affects the user experience. At the same time, the shielding structure 20 can not only control the on-off state between the first through hole 13 and the outside and the area communicated with the outside at different centrifugal fan speeds, and then adjust the size of the balanced static pressure area at different impeller speeds, avoiding the generation of additional noise and air volume loss; but also cover the first through hole 13 when the centrifugal fan stops running, preventing foreign objects from entering the centrifugal fan.

[0046] Optionally, the diameter of the first through hole 13 is greater than or equal to 1 mm and less than or equal to 10 mm. In this way, while ensuring the communication between the first through hole 13 and the external environment, the above setting of the diameter of the first through hole 13 can improve the structural strength of the volute 10, and further extend the service life of the volute 10.

[0047] In this embodiment, the diameter of the first through hole 13 is 5 mm.

[0048] It should be noted that the value of the first through hole 13 is not limited to this and can be adjusted according to the working conditions and usage requirements. Optionally, the diameter of the first through hole 13 is 2 mm, or 3 mm, or 4 mm, or 6 mm, or 7 mm, or 8 mm, or 9 mm.

[0049] As Figures 1 to 6 and Figure 8 shown, the centrifugal fan further includes an impeller 80. The volute 10 includes a first cover plate 15, a volute body 16, and a second cover plate 17. The first cover plate 15 has a second through hole. The volute body 16 includes an arc-shaped side plate and a volute tongue 14. The first through hole 13 is provided on the arc-shaped side plate. The first cover plate 15 is covered on one side of the volute body 16. The second cover plate 17 is covered on the other side of the volute body 16 and has a third through hole. Among them, the first cover plate 15, the volute body 16, and the second cover plate 17 surround to form an air duct. The second through hole and the third through hole form an air inlet 11. The impeller 80 is arranged in the air duct. In this way, the above setting further ensures that the first through hole 13 is arranged close to the volute tongue 14, thereby effectively balancing the air static pressure inside the volute tongue and reducing the "turbulent kinetic energy" near the volute tongue, effectively weakening the aerodynamic noise of the centrifugal fan from the source. At the same time, the above setting makes the structure of the volute 10 simpler, easier to process and implement, and reduces the processing cost of the centrifugal fan.

[0050] Specifically, the first cover plate 15 and the second cover plate 17 are arranged parallel to each other.

[0051] Optionally, the opening ratio of the first through hole 13 on the volute body 16 is greater than or equal to 1% and less than or equal to 50%. In this way, while ensuring the connection between the first through hole 13 and the external environment, the above setting of the opening ratio of the first through hole 13 can improve the structural strength of the volute 10, and thus extend the service life of the volute 10.

[0052] In this embodiment, the opening ratio of the first through hole 13 on the volute body 16 is 30%.

[0053] It should be noted that the value of the opening ratio of the first through hole 13 is not limited to this and can be adjusted according to the working conditions and usage requirements. Optionally, the opening ratio of the first through hole 13 is 5%, or 8%, or 10%, or 15%, or 20%, or 25%, or 35%, or 40%, or 45%.

[0054] Optionally, there are multiple first through holes 13, and the multiple first through holes 13 are arranged at intervals along the thickness direction of the volute body 16 and / or the circumferential direction of the arc-shaped side plate. In this way, the above setting makes the distribution of the first through holes 13 on the volute body 16 more flexible and diverse to meet different usage requirements and working conditions, and also improves the processing flexibility of the staff.

[0055] In this embodiment, a plurality of first through holes 13 are arranged at intervals along the thickness direction of the volute body 16 and the circumferential direction of the arc-shaped side plate.

[0056] In other embodiments not shown in the drawings, a plurality of first through holes are arranged at intervals along the thickness direction of the volute body.

[0057] In other embodiments not shown in the drawings, a plurality of first through holes are arranged at intervals along the circumference of the arc-shaped side plate.

[0058] like Figure 7 As shown, the centrifugal fan further includes a first drive device 30 and a transmission assembly. The first drive device 30 is connected to the shielding structure 20 through the transmission assembly to drive the shielding structure 20 to move between the shielding position and the avoidance position. In this way, the above arrangement improves the automation level of the shielding structure 20, thereby reducing the labor intensity of the staff. At the same time, the above arrangement makes the movement of the shielding structure 20 more stable, avoids vibration and noise, and improves the user experience.

[0059] like Figure 7 As shown, the first driving device 30 has a driving shaft 31, and the transmission assembly includes a gear structure 41 and a rack structure 42. The gear structure 41 is drivingly connected to the driving shaft 31, and the rack structure 42 is arranged on the shielding structure 20, and the rack structure 42 is meshed with the gear structure 41; the extension direction of the rack structure 42 is consistent with the movement direction of the shielding structure 20. In this way, after starting the first driving device 30, the driving shaft 31 of the first driving device 30 drives the gear structure 41 to rotate synchronously, and the gear structure 41 drives the rack structure 42 meshed therewith to move, thereby driving the shielding structure 20 to switch between the shielding position and the avoidance position, so as to adjust the on-off state of the first through hole 13 and the outside world and the area connected to the outside world.

[0060] Optionally, the first driving device 30 is a motor, and the driving shaft 31 is a motor shaft.

[0061] like Figure 6As shown, the centrifugal fan also includes a first matching portion 50 and a second matching portion. The first matching portion 50 is arranged on the volute 10, and the second matching portion is arranged on the shielding structure 20. Among them, one of the first matching portion 50 and the second matching portion is a protrusion, and the other of the first matching portion 50 and the second matching portion is a recessed portion, and the protrusion extends into the recessed portion to slide along the extension direction of the recessed portion; the extension direction of the recessed portion is consistent with the movement direction of the shielding structure 20. In this way, in the process of the first driving device 30 driving the shielding structure 20 to move, the above-mentioned setting of the first matching portion 50 and the second matching portion increases the contact area between the shielding structure 20 and the volute 10, thereby improving the movement stability of the shielding structure 20, and avoiding the two from separating from each other and affecting the normal use of the shielding structure 20. At the same time, the above-mentioned setting makes the structural selection of the first matching portion 50 and the second matching portion more flexible to meet different usage requirements and working conditions.

[0062] In this embodiment, the first matching portion 50 is a protrusion, and the second matching portion is a recess. The protrusion extends into the recess to slide along the extension direction of the recess; the extension direction of the recess is consistent with the movement direction of the shielding structure 20.

[0063] Optionally, there is one first matching portion 50 ; or, there are multiple first matching portions 50 , and the multiple first matching portions 50 are arranged at intervals along the thickness direction of the volute 10 .

[0064] Optionally, there is one second matching portion; or, there are multiple second matching portions, and the multiple second matching portions are arranged in a one-to-one correspondence with the multiple first matching portions 50 .

[0065] like Figure 7 As shown, the centrifugal fan further includes a bracket 60, which is arranged on the first cover plate 15, and the first drive device 30 is installed on the volute 10 through the bracket 60. The bracket 60 is located outside the air duct. In this way, the above arrangement makes the disassembly and assembly of the first drive device 30 easier and simpler, and reduces the difficulty of disassembly and assembly.

[0066] Optionally, there is one rack structure 42; or, there are multiple rack structures 42, and the multiple rack structures 42 are spaced apart along the thickness direction of the volute 10; and / or, the rack structure 42 is located on the side of the shielding structure 20 away from the first through hole 13; and / or, the centrifugal fan also includes a limiting structure 70, and during the movement of the shielding structure 20, the limiting structure 70 is used to limit and stop the shielding structure 20.

[0067] In this embodiment, there is only one rack structure 42, so that the structure of the transmission assembly is simpler, easier to process and realize, and the processing cost and difficulty of the centrifugal fan are reduced.

[0068] In this embodiment, the first driving device 30 is located outside the volute 10, which makes the maintenance and replacement of the first driving device 30 easier and simpler, and reduces the operation difficulty of the staff.

[0069] Optionally, the first through hole 13 is a circular hole, or a polygonal hole, or an oval hole.

[0070] In this embodiment, the control principle of the shielding structure 20 is as follows:

[0071] First, identify the startup state of the centrifugal fan. If it is started up, then continue to identify the wind gear of the centrifugal fan. If it is in the first gear, then control the first driving device 30 to drive the shielding structure 20 to shield 3 / 4 of the opening area of the first through hole 13; if it is in the second gear, then control the first driving device 30 to drive the shielding structure 20 to shield 1 / 2 of the opening area of the first through hole 13; if it is in the third gear, then control the first driving device 30 to drive the shielding structure 20 to shield 1 / 4 of the opening area of the first through hole 13; if it is in the fourth gear, then control the first driving device 30 to drive the shielding structure 20 to move to not shield the first through hole 13; if it is identified that the centrifugal fan is in the shutdown state, then control the first driving device 30 to drive the shielding structure 20 to move to completely shield the first through hole 13.

[0072] As Figure 8 shown, reinforcing ribs 18 are arranged on the surface of the second cover plate 17 away from the first cover plate 15.

[0073] As Figure 5 shown, the centrifugal fan further includes a second driving device 90, and the second driving device 90 is drivingly connected to the impeller 80 to drive the impeller 80 to rotate.

[0074] As Figure 9 and Figure 10 shown, the comparison between the two shows that the above setting of the first through hole 13 can improve the static pressure of the volute 10 at this place and can effectively reduce the oscillation of air particles caused by static pressure imbalance.

[0075] As Figure 11 and Figure 12 shown, the comparison between the two shows that the above setting of the first through hole 13 can reduce the turbulent kinetic energy of the volute 10 at this place.

[0076] As Figure 13 shown, the average sound pressure level of the centrifugal fan in this embodiment is reduced by 10.6 dB compared with that in Comparative Examples 100 to 5000 Hz, that is, the noise of the centrifugal fan in this embodiment is greatly improved compared with the noise of the centrifugal fan in the prior art.

[0077] This application also provides an air-conditioning device (not shown), including the above-mentioned centrifugal fan.

[0078] As can be seen from the above description, the above embodiments of the present utility model achieve the following technical effects:

[0079] The centrifugal fan includes a volute and a shielding structure. The volute has an air inlet, an air outlet, a first through hole, and an air duct. The air inlet is communicated with the air outlet through the air duct, and the first through hole is communicated with the air duct. The first through hole is arranged near the volute tongue of the volute. The shielding structure is movably arranged at the first through hole to shield or avoid at least part of the first through hole. Wherein, when the shielding structure avoids the first through hole, the first through hole is communicated with both the air duct and the environment where the centrifugal fan is located. In this way, by opening the first through hole in the part near the volute tongue to communicate with the external environment, the air static pressure inside the volute tongue is effectively increased, the air static pressure near the volute tongue is balanced, the "turbulent kinetic energy" is reduced, and thus the aerodynamic noise of the centrifugal fan is effectively weakened from the source, solving the problem that the centrifugal fan in the prior art generates a large amount of noise during operation, which affects the user experience. At the same time, the shielding structure can not only control the on-off state between the first through hole and the outside and the area communicated with the outside at different rotational speeds of the centrifugal fan, thereby adjusting the size of the balanced static pressure area at different rotational speeds of the impeller and avoiding additional noise and air volume loss; but also cover the first through hole when the centrifugal fan stops running to prevent foreign objects from entering the centrifugal fan.

[0080] Obviously, the above-described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0081] It should be noted that the terms used herein are only for describing specific embodiments, and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0082] It should be noted that the terms "first", "second", etc. in the description, claims, and drawings of the present application 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 under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0083] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, various modifications and variations can be made to the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A centrifugal fan, characterized in that: include: A volute (10) having an air inlet (11), an air outlet (12), a first through hole (13) and an air duct, wherein the air inlet (11) is connected to the air outlet (12) through the air duct, and the first through hole (13) is connected to the air duct; the first through hole (13) is arranged close to a volute tongue (14) of the volute (10); A shielding structure (20), wherein the shielding structure (20) is movably arranged at the first through hole (13) to shield or avoid at least a portion of the first through hole (13); wherein, when the shielding structure (20) avoids the first through hole (13), the first through hole (13) is connected to both the air duct and the environment in which the centrifugal fan is located.

2. The centrifugal fan according to claim 1, characterized in that: The diameter of the first through hole (13) is greater than or equal to 1 mm and less than or equal to 10 mm.

3. The centrifugal fan according to claim 1, characterized in that: The centrifugal fan further comprises an impeller (80), and the volute (10) comprises: A first cover plate (15) having a second through hole; A volute body (16) comprises an arc-shaped side plate and the volute tongue (14), wherein the first through hole (13) is arranged on the arc-shaped side plate, and the first cover plate (15) is covered on one side of the volute body (16); a second cover plate (17), which is disposed on the other side of the volute body (16) and has a third through hole; The first cover plate (15), the volute body (16) and the second cover plate (17) surround and form the air duct, the second through hole and the third through hole form the air inlet (11), and the impeller (80) is arranged in the air duct; the opening rate of the first through hole (13) on the volute body (16) is greater than or equal to 1% and less than or equal to 50%.

4. The centrifugal fan according to claim 3, characterized in that: There are a plurality of the first through holes (13), and the plurality of the first through holes (13) are arranged at intervals along the thickness direction of the volute body (16) and / or the circumferential direction of the arc-shaped side plate.

5. The centrifugal fan according to claim 3, characterized in that: The centrifugal fan also includes: A first driving device (30); A transmission assembly, wherein the first driving device (30) is drivingly connected to the shielding structure (20) via the transmission assembly, so as to drive the shielding structure (20) to move between a shielding position and an avoidance position.

6. The centrifugal fan according to claim 5, characterized in that: The first driving device (30) has a driving shaft (31), and the transmission assembly comprises: A gear structure (41) drivingly connected to the drive shaft (31); A rack structure (42) is arranged on the shielding structure (20), and the rack structure (42) is meshed with the gear structure (41); the extension direction of the rack structure (42) is consistent with the movement direction of the shielding structure (20).

7. The centrifugal fan according to claim 1, characterized in that: The centrifugal fan also includes: A first matching portion (50) is arranged on the volute (10); A second matching portion, arranged on the shielding structure (20); One of the first matching portion (50) and the second matching portion is a protrusion, and the other of the first matching portion (50) and the second matching portion is a recessed portion, and the protrusion extends into the recessed portion to slide along the extension direction of the recessed portion; the extension direction of the recessed portion is consistent with the movement direction of the shielding structure (20).

8. The centrifugal fan according to claim 5, characterized in that: The centrifugal fan also includes: a bracket (60) disposed on the first cover plate (15), wherein the first driving device (30) is mounted on the volute (10) via the bracket (60); Wherein, the bracket (60) is located outside the air duct.

9. The centrifugal fan according to claim 6, characterized in that: The rack structure (42) is one; or, the rack structure (42) is multiple, and the multiple rack structures (42) are arranged at intervals along the thickness direction of the volute (10); and / or, The rack structure (42) is located on a side of the shielding structure (20) away from the first through hole (13); and / or, The centrifugal fan further comprises a limiting structure (70), and during the movement of the shielding structure (20), the limiting structure (70) is used to limit and stop the shielding structure (20).

10. An air conditioning device, characterized in that: A centrifugal fan comprising any one of claims 1 to 9.

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