Centrifugal fan and extractor hood

Abstract

The application provides a centrifugal fan and a range hood, the centrifugal fan comprising an impeller, a volute and a guide ring assembly, the volute having a first side shell and a second side shell arranged oppositely, the guide ring assembly having a first end and a second end, the first end being arranged on the first side shell, the second end being arranged on the second side shell, and the guide ring assembly being formed with a flow guide channel and a receiving cavity between the first end and the second end, the receiving cavity extending from the first end to the second end, a plurality of through holes being arranged on the receiving cavity, the impeller being arranged in the receiving cavity, and the flow guide channel extending from the first end and being at least partially located in the receiving cavity. According to the centrifugal fan, airflow is guided into the receiving cavity through the flow guide channel, and then orderly discharged from the through holes under the action of the impeller, so that the vortex or turbulent flow is avoided, the noise is reduced, and the performance of the centrifugal fan is improved.

Description

TECHNICAL FIELD

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

[0002] As a core component of the range hood, the centrifugal fan plays a decisive role in smoke suction effect. The centrifugal fan includes a volute and an impeller arranged in the volute. When the range hood is running, the impeller rotates to form a negative pressure inside the volute, and the airflow enters the volute through the air guide ring. At present, the air guide ring only has a flow guiding function. After the airflow enters the impeller, vortex or turbulent flow is easily generated, thereby generating a large noise and affecting the use performance of the range hood. SUMMARY

[0003] In order to at least partially solve the problems existing in the prior art, according to one aspect of the present application, a centrifugal fan is provided, and the technical scheme is as follows.

[0004] The centrifugal fan includes an impeller and a volute. The volute has a first side shell and a second side shell arranged oppositely. The centrifugal fan further includes an air guide ring assembly. The air guide ring assembly has a first end and a second end. The first end is arranged on the first side shell, and the second end is arranged on the second side shell. The air guide ring assembly forms a flow guiding channel and a receiving cavity between the first end and the second end. The receiving cavity extends from the first end to the second end. A plurality of through holes are arranged on the receiving cavity. The impeller is arranged in the receiving cavity. The flow guiding channel extends from the first end and is at least partially located in the receiving cavity.

[0005] The centrifugal fan of the present application has the following advantages. On the one hand, based on the flow guiding channel extending into the receiving cavity, the airflow can flow into the receiving cavity under the guidance of the flow guiding channel, thereby improving the airflow turbulence condition when entering the impeller. On the other hand, the impeller is arranged in the receiving cavity with the through holes. The airflow in the receiving cavity can be orderly discharged from the through holes, thereby improving the airflow turbulence condition when flowing out of the impeller. That is, the airflow turbulence condition when entering and flowing out of the impeller is improved, which can effectively reduce the vortex or turbulent flow of the airflow, thereby reducing the noise.

[0006] Exemplarily, the flow guiding channel has a penetration end away from the first end. The flow guiding channel has a flow guiding inner diameter D1 at the penetration end. The receiving cavity has a diameter D2. The impeller includes a disc body having an inner circle and an outer circle. The diameter of the inner circle is D3, and the diameter of the outer circle is D4. D1 < D3, and D2 > D4. In this way, the impeller can be arranged in the receiving cavity, and the airflow can be guided to the inside of the impeller, thereby avoiding the phenomenon of vortex or turbulent flow when the airflow enters the impeller.

[0007] Exemplarily, the disc body comprises a first disc and a second disc, the first disc is arranged in a spaced manner with the second disc, and the first disc and the second disc have a spacing H1 therebetween, and the accommodating cavity has a height H2 from the first end to the second end, H2>H1. In this way, all the exhaust positions of the impeller are located inside the accommodating cavity, and the situation that the gas flows out from the part of the impeller not covered by the accommodating cavity and vortex phenomenon are avoided.

[0008] Exemplarily, the air guide ring assembly comprises a flow guide member and a flow regulating member; the flow guide member defines a flow guide channel which gradually decreases in the air inlet direction; the flow regulating member is connected to the flow guide member, and the flow regulating member defines an accommodating cavity, and a plurality of through holes are arranged on the flow regulating member; wherein, the connection part of the flow regulating member and the flow guide member forms a first end. In this way, the flow guide member can effectively guide the air flow to enter the accommodating cavity quickly and orderly in the air inlet direction, thereby increasing the flow capacity of the air flow in a certain time and a certain flow guide channel, and the air flow can be orderly discharged through the plurality of through holes, avoiding the collision between the air flow and the impeller to generate noise.

[0009] Exemplarily, the flow regulating member comprises a first mounting portion, a flow regulating portion and a second mounting portion, the flow regulating portion is connected to the flow guide member through the first mounting portion, the second mounting portion is connected to one end of the flow regulating portion away from the first mounting portion, the flow regulating portion encloses to form an accommodating cavity, and a plurality of through holes are arranged on the flow regulating portion. In this way, the flow regulating member has the first mounting portion and the second mounting portion, both ends of the flow regulating member are installed and fixed, so that the stability of the flow regulating member is enhanced, avoiding the accidental falling of the flow regulating member caused by a large amount of air flow, so that the air flow can be continuously discharged from the plurality of through holes of the flow regulating portion, and a stable flow regulating effect is achieved.

[0010] Exemplarily, the flow guide member comprises a ring-shaped guide portion, the ring-shaped guide portion has a first guide end and a second guide end, the first guide end is located inside the accommodating cavity, and the second guide end is located outside the accommodating cavity. In this way, the external air flow can be accurately and quickly guided into the accommodating cavity.

[0011] Exemplarily, the flow guide member comprises an extension portion, the extension portion extends from the second guide end in a radial direction away from the first guide end, and the first mounting portion is connected to the extension portion. In this way, the flow guide member and the flow regulating member are connected integrally, avoiding the air flow from being discharged between the flow guide member and the flow regulating member, and the situation that the air flow appears vortex or turbulence between the flow guide member and the flow regulating member.

[0012] Exemplarily, the longitudinal section of the ring-shaped guide portion is arc-shaped. In this way, the friction and resistance to the air flow are reduced, the air flow enters the accommodating cavity more smoothly, and the air flow is effectively guided.

[0013] Exemplarily, the rectifying part is enclosed by the mesh. In this way, the mesh holes uniformly arranged on the mesh form the through holes, which not only can make the airflow orderly discharged to the outside, reduce the vortex and turbulence phenomenon, but also the rectifying part is simple to manufacture and low in cost.

[0014] Exemplarily, the through holes are multiple, and the multiple through holes are arranged in a matrix on the development plane of the rectifying part. In this way, the airflow can be orderly discharged from the through holes, effectively reducing the generation of vortex and turbulence.

[0015] Exemplarily, the through holes have an area S1, and S1 is 2mm2-65mm2. In this way, not only can the problem of too small area of the through holes leading to poor air exhaust, too much airflow retention and vortex or turbulence be avoided, but also the problem of too large area of the through holes leading to too fast airflow discharge and no rectifying effect can be avoided.

[0016] Exemplarily, the sum of the areas of the multiple through holes is S2, the rectifying part has a development area S3, and S2:S3 is 0.4-0.8. In this way, the opening rate of the rectifying part is set to 40%-80%, which not only avoids the problem of too low opening rate leading to poor air exhaust and weakened rectifying effect, but also avoids the problem of too high opening rate leading to too fast airflow discharge through the rectifying part and no rectifying effect.

[0017] Exemplarily, the impeller comprises a blade group having a through airflow channel, the blade group is connected between a first disc and a second disc, the first disc and the second disc each comprise an inner ring and an outer ring, a first disc body is formed between the inner ring of the first disc and the outer ring of the first disc, a second disc body is formed between the inner ring of the second disc and the outer ring of the second disc, and at least one of the first disc body and the second disc body is configured as an arc-shaped part concave towards the blade group. In this way, after the airflow enters the blade group, the first disc body shields part of the airflow close to the end of the through airflow channel of the first disc, the second disc body shields part of the airflow close to the end of the through airflow channel of the second disc, and the arc-shaped part avoids the shielded part of the airflow from being turned too large, causing flow separation of the airflow and vortex of the airflow at the end of the impeller. In this way, the airflow can smoothly flow outwards, avoiding the impact of the backflow vortex on the blade group to generate noise, thereby achieving the purpose of reducing noise.

[0018] Exemplarily, the blade group has a first connecting end and a second connecting end, the through airflow channel has a first port at the first connecting end and a second port at the second connecting end, the first disc body is arranged at the first connecting end to cover the first port, and the second disc body is arranged at the second connecting end to cover the second port. In this way, the airflow can flow outwards along the direction perpendicular to the central axis of the blade group, while shielding the area prone to airflow vortex to inhibit the formation of airflow vortex, thereby improving the smoothness of airflow flow and reducing the noise caused by airflow vortex.

[0019] Exemplarily, the arc-shaped part comprises a first arc-shaped part formed between the inner ring of the first disc and the outer ring of the first disc, the blade set comprises a plurality of blades, and there is a gap between two adjacent blades to form an air passage. Each blade is formed with a first arc-shaped matching part on one side corresponding to the first port, and the first arc-shaped matching part is attached to the first arc-shaped part. In this way, the first arc-shaped matching part and the first arc-shaped part can be more closely attached, the first port can be more tightly shielded, and the situation that the airflow near the first port is turned too much and causes backflow vortex at the end of the air passage can be avoided, thereby achieving the purpose of reducing noise.

[0020] Exemplarily, the arc-shaped part comprises a second arc-shaped part formed between the inner ring of the second disc and the outer ring of the second disc, the blade set comprises a plurality of blades, and there is a gap between two adjacent blades to form an air passage. Each blade is formed with a second arc-shaped matching part on one side corresponding to the second port, and the second arc-shaped matching part is attached to the second arc-shaped part. In this way, the second arc-shaped matching part and the second arc-shaped part can be more closely attached, the second port can be more tightly shielded, and the situation that the airflow near the second port is turned too much and causes backflow vortex at the end of the air passage can be avoided, thereby achieving the purpose of reducing noise.

[0021] Exemplarily, the arc-shaped part comprises a first arc-shaped part and a second arc-shaped part, the first arc-shaped part is formed between the inner ring of the first disc and the outer ring of the first disc, the second arc-shaped part is formed between the inner ring of the second disc and the outer ring of the second disc, the blade set comprises a plurality of blades, and there is a gap between two adjacent blades to form an air passage. Each blade is formed with a first arc-shaped matching part on one side corresponding to the first port, and the first arc-shaped matching part is attached to the first arc-shaped part. Each blade is formed with a second arc-shaped matching part on one side corresponding to the second port, and the second arc-shaped matching part is attached to the second arc-shaped part. In this way, the first arc-shaped matching part and the first arc-shaped part can be more closely attached, the second arc-shaped matching part and the second arc-shaped part can be more closely attached, and the first port and the second port of the air passage can be better shielded, thereby ensuring that the airflow near the two ends of the air passage is shielded, avoiding the situation that the airflow near the two ends of the air passage is turned too much and causes backflow vortex at the two ends of the air passage, thereby achieving the purpose of reducing noise.

[0022] Exemplarily, the first disc body is provided with a first insertion hole, the first arc-shaped matching part is extended with a first insertion part, the first insertion part passes through the first insertion hole and is bent to clasp the first disc body. In this way, the fixing method of the first disc is simple, which is conducive to improving the installation efficiency, and the shielding effect of the airflow near the first port is not damaged due to the fixing of the first disc, and the situation that backflow vortex is generated at the first port due to the fixing of the first disc is avoided.

[0023] Exemplarily, the second disc body is provided with a second insertion hole, the second arc-shaped fitting part is extended with a second insertion part, the second insertion part passes through the second insertion hole and is bent to clasp the second disc body. In this way, the fixing mode of the second disc is simple, which is beneficial to improve the installation efficiency; and the shielding effect of the part of the airflow at the second port is not damaged due to the fixing of the second disc, and the situation of generating the backflow vortex at the second port due to the fixing of the second disc is avoided.

[0024] Exemplarily, the first arc-shaped part forms a circular arc with a radius R1, and the cross section of the blade forms a circular arc with a radius R2, and the ratio of R1 to R2 is 0.5-1.0. In this way, the cross-sectional area of the blade forms a circular arc, that is, the blade presents a certain arc shape, which can guide the airflow; the reasonable ratio of R1 to R2 limits the curvature of the blade, prevents the curvature from being too large to affect the smoothness of the airflow, and reduces the noise.

[0025] Exemplarily, the second arc-shaped part forms a circular arc with a radius R3, and the cross section of the blade forms a circular arc with a radius R2, and the ratio of R3 to R2 is 0.5-1.0. In this way, the cross-sectional area of the blade forms a circular arc, which can guide the airflow; the reasonable ratio of R3 to R2 limits the curvature of the blade, prevents the curvature from being too large to affect the smoothness of the airflow, and reduces the noise.

[0026] Exemplarily, the ratio of D4 to D3 is 1.1-1.4. In this way, it is beneficial to the first disc body and the second disc body to effectively shield the end of the air passage, and to avoid the airflow entering the air passage from overflowing from the end of the air passage.

[0027] Exemplarily, in the direction of the central axis of the blade group, the inner circle of the first disc is farther away from the blade group than the outer circle of the first disc, and the inner circle of the second disc is farther away from the blade group than the outer circle of the second disc. In this way, the first disc and the second disc are mirror image arranged, which can suppress the airflow vortex at both ends of the impeller, and further reduce the noise.

[0028] Exemplarily, the first disc has a first distance B1 between the outer circle of the first disc and the outer circle of the second disc, and a second distance B2 between the inner circle of the first disc and the inner circle of the second disc, and the ratio of B2 to B1 is 1.0-1.3. In this way, it is beneficial to accelerate the exhaust of the airflow and avoid generating airflow vortex, so as to achieve the purpose of reducing the noise.

[0029] According to another aspect of the present application, a range hood is also provided, which comprises a body and the centrifugal fan as described above, and the centrifugal fan is arranged on the body.

[0030] A series of simplified concepts are introduced in the description of the invention, which will be further explained in detail in the detailed description section. This description is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0031] The advantages and features of the present invention will be described in detail below with reference to the accompanying drawings. Attached Figure Description

[0032] The following figures are included as part of this invention for understanding its principles. The figures illustrate embodiments of the invention and their descriptions, serving to explain the principles of the invention. In the figures,

[0033] Figure 1 A front view of a centrifugal fan, as shown in an exemplary embodiment of the present invention;

[0034] Figure 2 for Figure 1 The diagram shows the internal structure of the centrifugal fan.

[0035] Figure 3 for Figure 2 A perspective view of the air guide ring assembly in the centrifugal fan shown;

[0036] Figure 4 for Figure 3 An exploded view of the air guide ring assembly shown;

[0037] Figure 5 for Figure 3 The sectional view of the air guide ring assembly shown;

[0038] Figure 6 for Figure 3 A perspective view of the air guide element in the air guide ring assembly shown;

[0039] Figure 7 for Figure 6 The front view of the guide component is shown;

[0040] Figure 8 for Figure 6 A top view of the flow guide shown;

[0041] Figure 9 for Figure 3 The diagram shows the unfolded plan view of the rectifier section in the air guide assembly.

[0042] Figure 10 The unfolded plan view of the rectifier section with a polygonal through-hole shape;

[0043] Figure 11 The plan view of the rectifier section with a horizontally rectangular through-hole;

[0044] Figure 12 An expanded plan view of a rectifier portion in the shape of a vertical rectangle for a through-hole;

[0045] Figure 13 An expanded plan view of a rectifier portion in the shape of a rectangle for a through-hole;

[0046] Figure 14 An expanded plan view of a rectifier portion in the shape of a diamond for a through-hole;

[0047] Figure 15 A perspective view of an impeller shown in Figure 2

[0048] Figure 16 An exploded view of an impeller shown in Figure 15

[0049] Figure 17 A front view of an impeller shown in Figure 15

[0050] Figure 18 A side sectional view of an impeller shown in Figure 17

[0051] Figure 19 A perspective view of a first disk in Figure 16

[0052] Figure 20 A perspective view of a second disk in Figure 16

[0053] Figure 21 A perspective view of a vane in Figure 16

[0054] Figure 22 A B-B sectional view in Figure 21

[0055] Wherein, the above-mentioned drawings include the following reference signs:

[0056] ​​​​​​​​10, impeller; 110, first disc; 111, first disc body; 1111, first insertion hole; 112, first arc-shaped part; 120, second disc; 121, second disc body; 1211, second insertion hole; 122, second arc-shaped part; 130, blade group; 1301, first connecting end; 1302, second connecting end; 1310, blade; 13111, first arc-shaped matching part; 13112, first insertion part; 13121, second arc-shaped matching part; 13122, second insertion part; 1320, air passage; 13201, air inlet; 13202, air outlet; 13203, first port; 13204, second port; 140, third disc; 1411, third insertion hole; 20, air guide ring assembly; 2010, air guide channel; 2011, insertion end; 2020, accommodating cavity; 2021, through hole; 201, first end; 202, second end; 210, air guide member; 2110, annular guide part; 2111, first guide end; 2112, second guide end; 2120, extension part; 220, rectifier member; 2210, first mounting part; 2220, rectifying part; 2230, second mounting part; 30, volute; 31, first side shell; 32, second side shell; 33, third side shell. DETAILED DESCRIPTION

[0057] In the following description, numerous specific details are provided for a thorough understanding of the present application. One of ordinary skill in the art will recognize, however, that the application can be practiced without one or more of these specific details. In other instances, well-known structures and processes have not been described in order not to unnecessarily obscure the present application.

[0058] For a thorough understanding of the present application, reference is made to the following detailed description taken in conjunction with the accompanying drawings. It is apparent that the present application can be practiced without one or more of the specific details set forth herein. Certain characteristics described herein are well known to those skilled in the art and are not described in detail in order to not unnecessarily obscure the present application.

[0059] Embodiments of the present application provide a centrifugal fan. The centrifugal fan can be applied in various fields, such as daily life, machine manufacturing, aerospace field, etc. Preferably, the centrifugal fan is applied in the cooking field, for example, the centrifugal fan is applied in a range hood. Hereinafter, the centrifugal fan according to embodiments of the present application will be described in detail with reference to the accompanying drawings.

[0060] Reference will now be made to Figures 1 to 3The centrifugal fan can include an impeller 10 and a volute 30. The volute 30 can define an air inlet, and the volute 30 can have a first side shell 31, a second side shell 32, and a third side shell 33. The first side shell 31 is arranged opposite to the second side shell 32, and the third side shell 33 is connected between the first side shell 31 and the second side shell 32. The centrifugal fan can further include a guide ring assembly 20. The guide ring assembly 20 can have a first end 201 and a second end 202. The first end 201 can be arranged on the first side shell 31, and the second end 202 can be arranged on the second side shell 32. The guide ring assembly 20 can form a flow guide channel 2010 and a receiving cavity 2020 between the first end 201 and the second end 202. The receiving cavity 2020 can extend from the first end 201 to the second end 202, and a plurality of through holes 2021 can be arranged on the receiving cavity 2020. The impeller 10 can be arranged in the receiving cavity 2020, and the flow guide channel 2010 can extend from the first end 201 and at least partially located in the receiving cavity 2020. Here, a part of the flow guide channel 2010 is located outside the receiving cavity 2020, so that the external flow can be guided into the receiving cavity 2020 through the flow guide channel 2010.

[0061] The guide ring assembly 20 can be connected and fixed to the volute 30 by screws, and other connection methods such as welding and buckle connection are not excluded. Specifically, the first end 201 of the guide ring assembly 20 is fixedly connected to the first side shell 31 of the volute 30, and the second end 202 is fixedly connected to the second side shell 32 of the volute 30, so that the receiving cavity 2020 axially penetrates the volute.

[0062] The centrifugal fan of the present application can improve the airflow turbulence condition when entering the impeller 10 based on the flow guide channel 2010 extending into the receiving cavity 2020. The impeller 10 is arranged in the receiving cavity 2020 with through holes 2021, so that the airflow can be orderly discharged from the through holes 2021 when the impeller 10 discharges the airflow, thereby improving the airflow turbulence condition when flowing out of the impeller 10. That is, the airflow turbulence condition when entering and discharging the impeller 10 is improved, which can effectively reduce the vortex or turbulent flow of the airflow, thereby reducing the noise and improving the performance of the centrifugal fan.

[0063] In an embodiment of the present application, in combination with the above description Figure 5 and Figure 17, the flow guide channel 2010 can have an extended end 2011 away from the first end 201, the flow guide channel 2010 can have a flow guide inner diameter D1 at the extended end 2011, and the accommodating cavity 2020 can have a diameter D2. The impeller 10 can include a disc body having an inner circle and an outer circle, the diameter of the inner circle can be D3, and the diameter of the outer circle can be D4, D1 < D3, and D2 > D4. In this way, the impeller 10 can be arranged in the accommodating cavity 2020, and the airflow can be guided to the inside of the impeller 10, avoiding the phenomenon of vortex and turbulence when the airflow enters the impeller 10.

[0064] In an embodiment of the present application, referring to Figure 5 and Figure 18 , the disc body can include a first disc 110 and a second disc 120, the first disc 110 and the second disc 120 can be arranged at intervals, and the first disc 110 and the second disc 120 can have a spacing H1 therebetween, the accommodating cavity 2020 has a height H2 from the first end 201 to the second end 202, and H2 > H1. In this way, all the exhaust positions of the impeller 10 can be located inside the accommodating cavity 2020, avoiding the phenomenon of vortex when the gas flows out from the part of the impeller 10 not covered by the accommodating cavity 2020.

[0065] In an embodiment of the present application, referring to Figure 3 and Figure 4 , the air guide ring assembly 20 can include a flow guide 210 and a flow straightener 220; the flow guide 210 can define a flow guide channel 2010, and the flow guide channel 2010 can gradually decrease in the air inlet direction; the flow straightener 220 can be connected to the flow guide 210, the flow straightener 220 can define an accommodating cavity 2020, and a plurality of through holes 2021 can be arranged on the flow straightener 220; wherein the connection between the flow straightener 220 and the flow guide 210 can form the first end 201. The flow guide 210 and the flow straightener 220 can adopt an integrated structure, or can adopt a split structure, etc. The connection mode of the flow guide 210 and the flow straightener 220 can be welding, of course, other connection modes are not excluded, wherein the through holes 2021 opened on the flow straightener 220 can be located on part of the area of the flow straightener 220 (such as only on the flow straightening part 2220 described later), or can be located on the entire flow straightener 220. In this way, the flow guide 210 can effectively guide the airflow to enter the accommodating cavity 2020 quickly and orderly in the air inlet direction, thereby increasing the flow capacity of the airflow in a certain time and in a certain flow guide channel 2010, and the airflow can be orderly discharged through the plurality of through holes 2021, avoiding the collision between the airflow and the impeller 10 to generate noise.

[0066] In an embodiment of the present application, referring to Figure 4The rectifying member 220 can include a first mounting portion 2210, a rectifying portion 2220, and a second mounting portion 2230. The rectifying portion 2220 is connected to the flow guiding member 210 through the first mounting portion 2210, the second mounting portion 2230 is connected to one end of the rectifying portion 2220 away from the first mounting portion 2210, the rectifying portion 2220 encloses a receiving cavity 2020, and a plurality of through holes 2021 are arranged on the rectifying portion 2220. The first mounting portion 2210 and / or the second mounting portion 2230 can be formed by flanging the outer edge of the rectifying portion 2220, or can be detachably mounted relative to the rectifying portion 2220, for example, by threaded connection or buckle connection. The first mounting portion 2210 and / or the second mounting portion 2230 can have a shape similar to the cross section of the rectifying portion 2220, but other shapes are not excluded. The first mounting portion 2210 can be one, and the first mounting portion 2210 can be completely connected to the entire edge of the rectifying portion 2220. The first mounting portion 2210 can be multiple, and the first mounting portion 2210 can be connected to part of the edge of the rectifying portion 2220. The second mounting portion 2230 can be one, and the second mounting portion 2230 can be completely connected to the entire edge of the rectifying portion 2220. The second mounting portion 2230 can be multiple, and the second mounting portion 2230 can be connected to part of the edge of the rectifying portion 2220. In this way, the rectifying member 220 has the first mounting portion 2210 and the second mounting portion 2230, both ends of the rectifying member 220 are fixedly mounted, the stability of the rectifying member 220 is enhanced, accidental falling of the rectifying member 220 caused by a large amount of airflow is avoided, and the airflow can be continuously discharged from the plurality of through holes 2021 of the rectifying portion 2220, thereby achieving a stable rectifying effect. It should be understood that, in order to achieve the rectifying purpose and to avoid vortex or turbulent flow, the through holes 2021 are arranged on the entire area of the rectifying portion 2220.

[0067] When the air guide ring assembly 20 is mounted to the volute 30, a screw can pass through the connecting extension 2120 (which will be described later), the first mounting portion 2210, and the first side shell 31 to fix the first end 201 of the air guide ring assembly 20 to the first side shell 31, and a screw can pass through the second mounting portion 2230 and the second side shell 32 to fix the second end 202 of the air guide ring assembly 20 to the second side shell 32.

[0068] In one embodiment of the present application, in combination with the above description Figures 5 to 8The flow guide 210 can include a ring-shaped guide portion 2110, which can have a first guide end 2111 and a second guide end 2112. The first guide end 2111 can be located inside the accommodating cavity 2020, and the second guide end 2112 can be located outside the accommodating cavity 2020. The first guide end 2111 can be in the same plane as the protruding end 2011. The ring-shaped guide portion 2110 can be generally circular, but is not limited to other shapes such as a square ring or a polygonal ring. In this way, the external airflow can be accurately and quickly guided into the accommodating cavity 2020.

[0069] In one embodiment of the present application, referring to Figure 2 and Figure 8 , the flow guide 210 can include an extension portion 2120 extending radially from the second guide end 2112 away from the first guide end 2111. The first mounting portion 2210 is connected to the extension portion 2120. The extension portion 2120 can be one, and the extension portion 2120 can be connected to the entire edge of the second guide end 2112. The extension portion 2120 can be multiple, and the extension portion 2120 can be connected to part of the edge of the second guide end 2112. The number of extension portions 2120 and their positions can correspond one-to-one to the first mounting portion 2210, and of course can have other corresponding relationships of positions and quantities. In this way, the flow guide 210 is connected to the flow regulator 220 as a whole, avoiding the airflow from being discharged between the flow guide 210 and the flow regulator 220, and causing vortex or turbulent flow between the flow guide 210 and the flow regulator 220.

[0070] In one embodiment of the present application, referring to Figure 6 , the longitudinal section of the ring-shaped guide portion 2110 can be arc-shaped. Of course, it can also be other shapes, as long as it can gradually decrease the flow guide channel 2010 in the air inlet direction. In this way, the friction and resistance to the airflow are reduced, and the airflow is more smoothly introduced into the accommodating cavity 2020, thereby effectively guiding the airflow.

[0071] In one embodiment of the present application, referring to Figures 3 to 5 , the flow regulating portion 2220 can be enclosed by a mesh member. The shape enclosed by the mesh member can be generally cylindrical, or can be other shapes such as a square column. In this way, the uniformly arranged mesh holes on the mesh member form the through holes 2021, which not only allow the airflow to be orderly discharged to the outside, reducing vortex and turbulent flow, but also make the flow regulator 220 simple to manufacture and low in cost. As shown in Figure 9 , the mesh holes on the mesh member (i.e., the through holes 2021) can be circular holes; as shown in Figure 10As shown, the mesh holes (i.e. the through holes 2021) on the mesh member can be hexagonal; in an embodiment not shown, the mesh holes (i.e. the through holes 2021) on the mesh member can also be triangular holes, can also be quadrilateral holes, and can even be one or more of pentagonal holes or polygonal holes. As shown, Figure 11 As shown, the mesh member can be a horizontal grid mesh; as shown, Figure 12 As shown, the mesh member can be a vertical grid mesh; as shown, Figure 13 As shown, the mesh member can be a horizontal-vertical grid mesh; as shown, Figure 14 As shown, the mesh member can also be a diamond grid mesh; in an embodiment not shown, the mesh member can also be other forms of grid mesh.

[0072] In an embodiment of the present application, referring again to Figures 3 to 5 , the through holes 2021 can be multiple, and the multiple through holes 2021 can be arranged in rows and columns on the unfolded plane of the rectifier portion 2220. Of course, the through holes 2021 can be irregularly distributed on the unfolded plane of the rectifier portion 2220, etc. The through holes 2021 can include one or more of circular holes, triangular holes, quadrilateral holes, or polygonal holes. In this way, the airflow can be orderly discharged from the through holes 2021, effectively reducing the generation of vortex and turbulent flow.

[0073] In an embodiment of the present application, referring to Figures 9 to 14 , the through holes 2021 can have an area S1, S1 can be 2mm 2 ~65mm 2 , S1 is for example 2mm 2 , 10mm 2 , 30mm 2 , 50mm 2 , 65mm 2 , etc. If the area of the through holes 2021 is too small, a large amount of airflow will be stagnant in the accommodation cavity 2020, causing the airflow to collide with the inner wall of the accommodation cavity 2020 and easily produce noise. If the area of the through holes 2021 is too large, the airflow is discharged too quickly and does not have a rectifying effect. In an embodiment of the present application, the area of the through holes 2021 is set to 2mm 2 ~65mm 2 , which not only avoids the problem of too small area of the through holes 2021, causing poor air exhaust, too much airflow stagnation, and vortex or turbulent flow; but also avoids the problem of too large area of the through holes 2021, causing the airflow to be discharged too quickly and not having a rectifying effect.

[0074] In an embodiment of the present application, referring again to Figures 9 to 14The sum of the areas of the plurality of through holes 2021 can be S2, the rectifying member 220 can have an unfolded area S3, and S2:S3 can be 0.4-0.8. S2:S3 is, for example, 0.4, 0.6, 0.8, or the like. In this way, the opening ratio on the rectifying member 220 is set to 40%-80%, which not only avoids the problem of too low opening ratio leading to poor air exhaust and weakened rectifying effect, but also avoids the problem of too high opening ratio leading to too fast air exhaust speed when the airflow passes through the rectifying member 220 and failing to achieve the rectifying effect.

[0075] In one embodiment of the present application, in combination with the above Figures 15 to 18 The impeller 10 can include a blade set 130 having a through-flow passage 1320, the blade set 130 can be connected between the first disc 110 and the second disc 120, and the first disc 110 and the second disc 120 can each include an inner ring and an outer ring. The first disc body 111 can be formed between the inner ring of the first disc 110 and the outer ring of the first disc 110. The second disc body 121 can be formed between the inner ring of the second disc 120 and the outer ring of the second disc 120. At least one of the first disc body 111 and the second disc body 121 is configured as an arc-shaped portion recessed toward the blade set 130. Specifically, the first disc body 111 is configured as an arc-shaped portion recessed toward the blade set 130, and the second disc body 121 can be configured as a flat plate or other shapes; or the second disc body 121 is configured as an arc-shaped portion recessed toward the blade set 130, and the first disc body 111 can be configured as a flat plate or other shapes; or the first disc body 111 and the second disc body 121 are both configured as arc-shaped portions recessed toward the blade set 130, and of course can be configured as other shapes. After the blade set 130 is connected to the first disc 110 and the second disc 120, the blade set 130 can be generally cylindrical, and the blade set 130 can have other shapes or structures. In this way, after the airflow enters the blade set 130, the first disc body 111 shields part of the airflow close to the end of the through-flow passage 1320 of the first disc 110, and the second disc body 121 shields part of the airflow close to the end of the through-flow passage 1320 of the second disc 120. By means of the arc-shaped portion, the part of the airflow that is shielded is prevented from being turned too much, which causes flow separation of the airflow and the occurrence of airflow vortex at the end of the impeller 10. In this way, the airflow can flow out smoothly, the impact of the airflow vortex on the blade set 130 is avoided to generate noise, and the purpose of reducing noise is achieved.

[0076] The first disc 110 and the second disc 120 are both hollow discs. When the impeller 10 rotates, the air flow enters the air passage 1320 along the central axis P-P of the blade set 130 through the end of the impeller 10 (i.e. the hollow part of the first disc 110 and / or the hollow part of the second disc 120), and is discharged along the air passage 1320. The air passage 1320 forms an air inlet 13201 near the center of the blade set 130 and an air outlet 13202 away from the center of the blade set 130, so that the air flow can flow radially through the air passage 1320 and be discharged outwardly. In this process, the flow direction of the air flow changes from the axial direction of the impeller 10 to the radial direction, and an angle of rotation is formed. The angle of rotation of the air flow passing through the air passage 1320 near one end of the first disc 110 or the second disc 120 is the largest, and this part of the air flow will cause flow separation at the end of the blade set 130, and a backflow vortex is generated at the end of the impeller 10.

[0077] In one embodiment of the present application, in combination with Figure 16 and Figure 18 , the blade set 130 can have a first connecting end 1301 and a second connecting end 1302, the air passage 1320 can have a first port 13203 at the first connecting end 1301 and a second port 13204 at the second connecting end 1302, the first disc body 111 can be arranged at the first connecting end 1301 to cover the first port 13203, and the second disc body 121 can be arranged at the second connecting end 1302 to cover the second port 13204. In this way, the air flow can flow outwardly along a direction perpendicular to the central axis P-P of the blade set 130, and the area prone to air flow vortex is shielded to inhibit the formation of air flow vortex, thereby improving the smoothness of the air flow and reducing the noise caused by air flow vortex.

[0078] In one embodiment of the present application, in combination with Figure 18 , Figure 19 and Figure 21The arc-shaped portion can include a first arc-shaped portion 112 formed between the inner ring of the first disc 110 and the outer ring of the first disc 110. The vane set 130 can include a plurality of vanes 1310, and adjacent two vanes 1310 can have a gap therebetween to form an air passage 1320. The plurality of vanes 1310 of the vane set 130 can be sequentially and spaced arranged along the circumference of the first disc 110 and the second disc 120, and the spacing distance can be the same, and of course, other arrangement modes can be adopted. The plurality of vanes 1310 of the vane set 130 can be arranged in an arc shape, or can have other shapes, such as a rectangular shape, etc. Each vane 1310 can be formed with a first arc-shaped matching portion 13111 on the side corresponding to the first port 13203, and the first arc-shaped matching portion 13111 can be attached to the first arc-shaped portion 112. The first arc-shaped matching portion 13111 can have a similar bending degree to the first arc-shaped portion 112. The first arc-shaped portion 112 can have other shapes, such as a bevel or a flat plate, etc. The first arc-shaped matching portion 13111 can have a similar shape to the first arc-shaped portion 112, or can have other shapes, etc. In this way, the first arc-shaped matching portion 13111 can be more closely attached to the first arc-shaped portion 112, and the first port 13203 can be more tightly shielded, so that the air flow near the first port 13203 is not excessively bent, and the backflow vortex at the end of the air passage 1320 is avoided, thereby achieving the purpose of reducing noise.

[0079] In one embodiment of the present application, in combination with the description of Figure 18 , Figure 20 and Figure 21 , the arc-shaped portion can include a second arc-shaped portion 122 formed between the inner ring of the second disc 120 and the outer ring of the second disc 120. The vane set 130 can include a plurality of vanes 1310, and adjacent two vanes 1310 can have a gap therebetween to form an air passage 1320. Each vane 1310 can be formed with a second arc-shaped matching portion 13121 on the side corresponding to the second port 13204, and the second arc-shaped matching portion 13121 can be attached to the second arc-shaped portion 122. The second arc-shaped matching portion 13121 can have a similar bending degree to the second arc-shaped portion 122, and the second arc-shaped portion 122 can also have other shapes, such as a bevel or a flat plate, etc. The second arc-shaped matching portion 13121 can have a similar shape to the second arc-shaped portion 122, or can have other shapes, etc. In this way, the second arc-shaped matching portion 13121 can be more closely attached to the second arc-shaped portion 122, and the second port 13204 can be more tightly shielded, so that the air flow near the second port 13204 is not excessively bent, and the backflow vortex at the end of the air passage 1320 is avoided, thereby achieving the purpose of reducing noise.

[0080] In one embodiment of the present application, referring to Figures 18 to 21 The arc-shaped portion can include a first arc-shaped portion 112 formed between the inner ring of the first disc 110 and the outer ring of the first disc 110, and a second arc-shaped portion 122 formed between the inner ring of the second disc 120 and the outer ring of the second disc 120. The vane set 130 can include a plurality of vanes 1310, and adjacent two vanes 1310 can have a gap therebetween to form an air passage 1320. Each vane 1310 can be formed with a first arc-shaped fitting portion 13111 on a side corresponding to the first port 13203, which can be attached to the first arc-shaped portion 112, and a second arc-shaped fitting portion 13121 on a side corresponding to the second port 13204, which can be attached to the second arc-shaped portion 122. The first arc-shaped fitting portion 13111 can have a similar curvature to the first arc-shaped portion 112. The first arc-shaped portion 112 can have other shapes, such as a bevel or a flat plate, etc. The first arc-shaped fitting portion 13111 can have a similar shape to the first arc-shaped portion 112, or other shapes, etc. The second arc-shaped fitting portion 13121 can have a similar curvature to the second arc-shaped portion 122, and the second arc-shaped portion 122 can also have other shapes, such as a bevel or a flat plate, etc. The second arc-shaped fitting portion 13121 can have a similar shape to the second arc-shaped portion 122, or other shapes, etc. In this way, the first arc-shaped fitting portion 13111 and the first arc-shaped portion 112 can be more tightly attached, the second arc-shaped fitting portion 13121 and the second arc-shaped portion 122 can be more tightly attached, and the first port 13203 and the second port 13204 of the air passage 1320 can have better shielding effects, ensuring that the airflow at both ends of the air passage 1320 is shielded, avoiding the situation that the airflow at both ends of the air passage 1320 is turned too large, and causing backflow vortex at both ends of the air passage 1320, thereby achieving the purpose of reducing noise.

[0081] In one embodiment of the present application, referring to Figure 16 and Figure 21The first disc body 111 can be provided with a first insertion hole 1111, the first arc-shaped matching part 13111 can extend a first insertion part 13112, the first insertion part 13112 can pass through the first insertion hole 1111 and be bent to clasp the first disc body 111. The shape of the first insertion hole 1111 can be rectangular or circular, and the shape of the first insertion part 13112 is similar to the shape of the first insertion hole 1111 so that the first insertion part 13112 can be inserted into the first insertion hole 1111. The first insertion part 13112 can be integrally arranged with the blade 1310 or can be detachably arranged. The first insertion part 13112 can be made thin so that it can be bent and folded. Of course, a material that can be bent and folded can also be used. The number of the first insertion part 13112 and the first insertion hole 1111 can be one-to-one correspondence. In this way, the fixing method is simple, the installation efficiency is improved, the stability of the fixing is good, and other matching parts are not needed for fixing, thereby reducing the cost. Of course, this fixing method is not limited, and other threaded fixing or clamping connection can also be used.

[0082] In one embodiment of the present application, in combination with Figure 16 and Figure 21 , the second disc body 121 can be provided with a second insertion hole 1211, the second arc-shaped matching part 13121 can extend a second insertion part 13122, the second insertion part 13122 can pass through the second insertion hole 1211 and be bent to clasp the second disc body 121. The shape of the second insertion hole 1211 can be rectangular or circular, and the shape of the second insertion part 13122 is similar to the shape of the second insertion hole 1211 so that the second insertion part 13122 can be inserted into the second insertion hole 1211. The second insertion part 13122 can be integrally arranged with the blade 1310 or can be detachably arranged. The second insertion part 13122 can be made thin so that it can be bent and folded. Of course, a material that can be bent and folded can also be used. The number of the second insertion part 13122 and the second insertion hole 1211 can be one-to-one correspondence. In this way, the fixing method is simple, the installation efficiency is improved, the stability of the fixing is good, and other matching parts are not needed for fixing, thereby reducing the cost. Of course, this fixing method is not limited, and other threaded fixing or clamping connection can also be used.

[0083] In one embodiment of the present application, in combination with Figure 19 , Figure 21 and Figure 22, the first arc-shaped portion 112 can form a circular arc with a radius R1. The cross section of the blade 1310 can form a circular arc with a radius R2, and the ratio of R1 to R2 is 0.5-1.0, for example, the ratio of R1 to R2 can be 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, etc. In this way, the cross-sectional area of the blade 1310 forms a circular arc, that is, the blade 1310 presents a certain arc shape, which can guide the airflow; the reasonable ratio of R1 to R2 limits the curvature of the blade 1310, prevents the curvature from being too large to affect the smoothness of the airflow, and reduces noise.

[0084] In an embodiment of the present application, in combination with Figures 20 to 22 , the longitudinal section of the second disc 120 can form a circular arc with a radius R3. The cross section of the blade 1310 can form a circular arc with a radius R2, and the ratio of R3 to R2 is 0.5-1.0, for example, the ratio of R1 to R2 can be 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, etc. In this way, the reasonable ratio of R3 to R2 limits the curvature of the blade 1310, prevents the curvature from being too large to affect the smoothness of the airflow, and reduces noise.

[0085] In an embodiment of the present application, in combination with Figure 17 , the first disc 110 and the second disc 120 can each include an inner ring and an outer ring, the diameter of the inner ring can be D3, and the diameter of the outer ring can be D4, and the ratio of D4 to D3 can be 1.1-1.4, for example, the ratio of D4 to D3 can be 1.1, 1.2, 1.3, 1.4, etc. In this way, it is beneficial for the first disc body 111 and the second disc body 121 to effectively block the end of the air passage 1320, preventing the airflow entering the air passage 1320 from overflowing from the end of the air passage 1320.

[0086] In an embodiment of the present application, in combination with Figure 17 , in the direction of the central axis P-P of the blade set 130, the inner ring of the first disc 110 is farther away from the blade set 130 than the outer ring of the first disc 110, and the inner ring of the second disc 120 is farther away from the blade set 130 than the outer ring of the second disc 120, in this way, the first disc 110 and the second disc 120 are mirror image arranged, which can suppress the airflow vortex at both ends of the impeller 10, further reducing noise.

[0087] In an embodiment of the present application, in combination with Figure 18, the first distance B1 between the outer circle of the first disc 110 and the outer circle of the second disc 120, the ratio of B2 to B1 can be 1.0-1.3, for example, the ratio of B2 to B1 is 1.0, 1.1, 1.2, 1.3, etc. By setting up in this way, it is beneficial to accelerate the outflow of air flow and avoid the generation of air flow vortex, so as to achieve the purpose of reducing noise. Here, the second distance B2 can be equal to the height H2 of the accommodating cavity 2020 from the first end 201 to the second end 202.

[0088] In an embodiment of the present application, referring again to Figures 15 to 18 , the first disc 110 and the second disc 120 can also be provided with a third disc 140. The third disc 140 can be provided with a plurality of third insertion holes 1411, and the plurality of blades 1310 can be respectively and correspondingly arranged in the plurality of third insertion holes 1411. The shape of the third insertion hole 1411 is similar to the shape of the cross section of the blade 1310. The number of the third insertion hole 1411 is the same as that of the first insertion hole 1111 and the second insertion hole 1211. Among them, the third disc 140 can be in the form of a flat plate or other shapes, etc. The plurality of blades 1310 are assembled together through the first disc 110, the second disc 120 and the third disc 140, and the motor can be connected to the third disc 140, so as to drive the whole impeller 10 to rotate by the motor. Based on the setting of the third disc 140, not only is it beneficial to assemble the plurality of blades 1310 into the blade group 130, but also meets the needs of motor installation.

[0089] According to another aspect of the present application, a kind of range hood is also provided, comprising body and the centrifugal fan as described above, and the centrifugal fan is arranged on the body. The above-mentioned centrifugal fan is applied to the range hood, avoids or reduces the generation of vortex and reduces noise, and further improves the effect of the range hood on absorbing oil fume, so that the phenomenon of oil fume returning or oil fume not being able to be timely discharged is not easy to occur, and the use experience of user is improved. Since the range hood adopts all the technical solutions of the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0090] In the description of the present application, it should be understood that the orientation words such as "front", "back", "up", "down", "left", "right", "transverse", "vertical", "vertical", "horizontal" and "top", "bottom" and the like indicate the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and in the absence of the opposite description, these orientation words do not indicate and imply that the indicated device or element must have a specific orientation or be constructed and operated in a specific orientation, therefore it cannot be understood as a limitation on the scope of protection of the present application; the orientation words "inner" and "outer" refer to the inner and outer of the contour of each component itself.

[0091] For purposes of the description hereinafter, the terms "upper", "lower", "right", "left", "rear", "front", "vertical", "horizontal", and derivatives thereof shall relate to the application as it is oriented in the drawing figures. However, it is to be understood that the application can assume various alternative orientations and, accordingly, such terms are not to be taken as limitations of the present application, except where so expressly defined by the patentee. All such terms are to be interpreted in the manner that the terms are construed in the section entitled, "Definition of Terms", recited below. It is also to be understood that the following description, together with the accompanying figures, will be used herein to describe the application.

[0092] It is to be understood that the terminology used herein is for the purpose of describing the particular embodiments only and is not intended to be limiting, unless the above context clearly dictates otherwise. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising", when used in this specification, specify the presence of stated features, steps, operations, components, elements, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, components, elements, and / or groups thereof.

[0093] It will be understood that the terms "first", "second", etc. are used herein solely to distinguish one element from another, without necessarily requiring or implying an order of precedence or sequence. It will be further understood that where a term is used in the singular, it is also intended to encompass the plural, unless the context clearly dictates otherwise.

[0094] The application has been described herein with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description, and it is intended to include all such modifications and alterations insofar as they come within the scope of the claims or the equivalent scope. It will be appreciated that those skilled in the art, upon attaining an understanding of the nature of the application, can readily devise their own modifications and alterations of the specific embodiments illustrated and described herein, without departing from the spirit and scope of the application. The scope of the application is to be limited only by the claims and equivalents thereof.

Claims

1. A centrifugal fan comprising an impeller and a volute having first and second side shells disposed opposite to each other, characterized in that, The centrifugal fan further comprises a guide ring assembly having a first end and a second end, the first end is arranged on the first side shell, the second end is arranged on the second side shell, and the guide ring assembly forms a guide passage and a receiving cavity between the first end and the second end, the receiving cavity extends from the first end to the second end, a plurality of through holes are arranged on the receiving cavity, the impeller is arranged in the receiving cavity, the guide passage extends from the first end and is at least partially located in the receiving cavity, the guide passage has an extending end away from the first end, the guide passage has an inner diameter D1 at the extending end, the receiving cavity has a diameter D2, the impeller comprises a disc body having an inner ring and an outer ring, the diameter of the inner ring is D3, the diameter of the outer ring is D4, D1 < D3, and D2 > D4.

2. The centrifugal fan of claim 1, wherein The disc body comprises a first disc and a second disc, the first disc and the second disc are arranged in a spaced manner, and the first disc and the second disc have a spacing H1, the receiving cavity has a height H2 from the first end to the second end, and H2 > H1.

3. The centrifugal fan of claim 1, wherein The guide ring assembly comprises a guide member and a rectifying member; The guide member defines the guide passage, and the guide passage gradually decreases in the air inlet direction; The rectifying member is connected to the guide member, the rectifying member defines the receiving cavity, and a plurality of through holes are arranged on the rectifying member; The connection between the rectifying member and the guide member forms the first end.

4. The centrifugal fan of claim 3, wherein The rectifying member comprises a first mounting portion, a rectifying portion, and a second mounting portion, the rectifying portion is connected to the guide member through the first mounting portion, the second mounting portion is connected to one end of the rectifying portion away from the first mounting portion, the rectifying portion encloses the receiving cavity, and a plurality of through holes are arranged on the rectifying portion.

5. The centrifugal fan of claim 4, wherein The guide member comprises an annular guide portion having a first guide end and a second guide end, the first guide end is located in the receiving cavity, and the second guide end is located outside the receiving cavity.

6. The centrifugal fan of claim 5, wherein The guide member comprises an extension portion extending radially from the second guide end away from the first guide end, and the first mounting portion is connected to the extension portion.

7. The centrifugal fan of claim 5, wherein The longitudinal section of the annular guide portion is arc-shaped.

8. The centrifugal fan of claim 4, wherein The rectifying portion is enclosed by a mesh member.

9. The centrifugal fan of claim 4, wherein The plurality of through holes are arranged in rows and columns on the development plane of the rectifying portion.

10. The centrifugal fan of claim 3, wherein The through hole has an area S1, S1 is 2 mm 2 65 mm 2 .

11. The centrifugal fan of claim 3, wherein The sum of the areas of the plurality of through holes is S2, the rectifying member has a development area S3, and S2:S3 is 0.4-0.

8.

12. The centrifugal fan of claim 2, wherein The impeller comprises a blade group having a ventilation flow channel, the blade group is connected between the first disc and the second disc, the first disc and the second disc both comprise the inner ring and the outer ring, the inner ring of the first disc and the outer ring of the first disc form a first disc body, the inner ring of the second disc and the outer ring of the second disc form a second disc body, and at least one of the first disc body and the second disc body is configured as an arc-shaped portion concave to the blade group.

13. The centrifugal fan of claim 12, wherein The vane set has a first connecting end and a second connecting end, the air passage has a first port at the first connecting end and a second port at the second connecting end, the first disc body is arranged at the first connecting end to cover the first port, and the second disc body is arranged at the second connecting end to cover the second port.

14. The centrifugal fan of claim 13, wherein The arc-shaped portion includes a first arc-shaped portion formed between the inner ring of the first disc and the outer ring of the first disc, the vane set includes a plurality of vanes, adjacent two vanes have a gap to form the air passage, each vane is formed with a first arc-shaped fitting portion on a side corresponding to the first port, and the first arc-shaped fitting portion is attached to the first arc-shaped portion.

15. The centrifugal fan of claim 13, wherein The arc-shaped portion includes a second arc-shaped portion formed between the inner ring of the second disc and the outer ring of the second disc, the vane set includes a plurality of vanes, adjacent two vanes have a gap to form the air passage, each vane is formed with a second arc-shaped fitting portion on a side corresponding to the second port, and the second arc-shaped fitting portion is attached to the second arc-shaped portion.

16. The centrifugal fan of claim 13, wherein The arc-shaped portion includes a first arc-shaped portion formed between the inner ring of the first disc and the outer ring of the first disc and a second arc-shaped portion formed between the inner ring of the second disc and the outer ring of the second disc, the vane set includes a plurality of vanes, adjacent two vanes have a gap to form the air passage, each vane is formed with a first arc-shaped fitting portion on a side corresponding to the first port and a second arc-shaped fitting portion on a side corresponding to the second port, the first arc-shaped fitting portion is attached to the first arc-shaped portion, and the second arc-shaped fitting portion is attached to the second arc-shaped portion.

17. The centrifugal fan according to claim 14 or 16, characterized in that The first disc body is provided with a first insertion hole, the first arc-shaped fitting portion is extended with a first insertion portion, the first insertion portion passes through the first insertion hole and is bent to clasp the first disc body.

18. The centrifugal fan according to claim 15 or 16, characterized in that The second disc body is provided with a second insertion hole, the second arc-shaped fitting portion is extended with a second insertion portion, the second insertion portion passes through the second insertion hole and is bent to clasp the second disc body.

19. The centrifugal fan according to claim 14 or 16, characterized in that The first arc-shaped portion forms a circular arc with a radius R1, the cross section of the vane forms a circular arc with a radius R2, and the ratio of R1 to R2 is 0.5-1.

0.

20. The centrifugal fan of claim 15 or 16, wherein The second arc-shaped portion forms a circular arc with a radius R3, the cross section of the vane forms a circular arc with a radius R2, and the ratio of R3 to R2 is 0.5-1.

0.

21. The centrifugal fan of claim 12, wherein The ratio of D4 to D3 is 1.1-1.

4.

22. The centrifugal fan of claim 12, wherein In the direction of the central axis of the vane set, the inner ring of the first disc is farther away from the vane set than the outer ring of the first disc, and the inner ring of the second disc is farther away from the vane set than the outer ring of the second disc.

23. The centrifugal fan of claim 12, wherein The outer ring of the first disc and the outer ring of the second disc have a first distance B1, and the inner ring of the first disc and the inner ring of the second disc have a second distance B2, and the ratio of B2 to B1 is 1.0-1.

3.

24. A range hood characterized by The centrifugal fan includes a body and a centrifugal fan as claimed in any one of claims 1-23, and the centrifugal fan is arranged on the body.

Images