Bilateral air suction centrifugal fan and air purifier

Abstract

The utility model relates to the technical field of air purification, in particular to a bilateral air suction centrifugal fan and an air purifier, the centrifugal fan comprises a volute, a centrifugal impeller and a motor, two sides of the volute are respectively provided with a first air inlet shell and a second air inlet shell which are used for air inlet, and the volute is further provided with an air outlet channel; the first air inlet shell and the second air inlet shell communicate with the air outlet channel. The motor is arranged on the first air inlet shell, and an output shaft of the motor is coaxially connected with the centrifugal impeller. The second air inlet shell is in a plane shape perpendicular to the output shaft of the motor, and the first air inlet shell is in a conical surface shape, so that the actual air inlet area of the first air inlet shell is enlarged, the air inlet amount difference between the two sides of the centrifugal impeller is reduced, and the load of the first air inlet channel and the load of the second air inlet channel at the two ends of the centrifugal impeller are close to or even consistent. Therefore, the risk of eccentric oscillation caused by uneven stress of the centrifugal impeller is reduced or even avoided, and the requirements for dynamic balance and manufacturing precision of the centrifugal impeller can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of air purification, and more specifically, to a double-sided air suction centrifugal fan and an air purifier. Background Art

[0002] In the structural design of the air purifier, since the motor installation cannot avoid blocking the size of the air inlet, the air intake volume at both ends of the product will be inconsistent, and the purification volume at both ends will also be inconsistent, resulting in differences in the life of the filters on both sides, and the overall purification efficiency cannot be balanced.

[0003] The prior art discloses a high-efficiency, large-air-volume, double-sided air-inlet impeller fan, in which two back-to-back impellers are connected together on an impeller center disk, and the impeller center disk is penetrated by hollow holes evenly distributed along its circumference. When the air intake of the impeller on the motor side is blocked by the motor, air can be smoothly supplied from the other side to make up for the imbalance defect on both sides. However, in fact, the air intake on both sides of the impeller is inconsistent. When used for air purification, the degree of use of the filters on both sides is different, resulting in differences in the life of the filters on both sides, and the overall purification efficiency cannot be balanced.

[0004] The prior art also discloses a noise-reducing centrifugal impeller and a range hood, comprising a rear disc and a plurality of blades fixed on the rear disc, wherein the blades are evenly distributed around the rear disc, and a preset distance is provided between two adjacent blades; the blades are composed of a leading edge of the blade close to the blade rotation axis and a trailing edge of the blade away from the blade rotation axis, and the leading edge of the blade is provided with a plurality of through holes penetrating the leading edge of the blade, and the width of the leading edge of the blade is less than or equal to 2 / 3 of the width of the blade. In this scheme, the purpose of uniform air intake on both sides is achieved by designing the width of different parts of the blade, but this structural design will have higher requirements on the manufacturing accuracy and dynamic balance of the impeller, and it is easy to cause the impeller to scrape the air duct. Utility Model Content

[0005] The utility model aims to overcome the deficiencies of the prior art and provide a double-sided suction centrifugal fan and an air purifier. By adjusting the inclination of the air inlet on the motor installation side, the sizes of the air inlet surfaces on both sides of the centrifugal fan are made consistent, thereby achieving uniform air intake on both sides. At the same time, the risk of eccentric oscillation caused by uneven force on the centrifugal impeller is avoided, thereby reducing the requirements for dynamic balance and manufacturing accuracy of the centrifugal impeller.

[0006] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0007] A double-sided suction centrifugal fan is provided, comprising a volute, a centrifugal impeller and a motor, wherein a first air inlet shell and a second air inlet shell for air intake are respectively provided on both sides of the volute, and the volute is provided with air outlet ducts respectively connected with the first air inlet shell and the second air inlet shell; a first air inlet duct and a second air inlet duct are respectively provided on both sides of the centrifugal impeller, the first air inlet shell is connected with the air outlet duct through the first air inlet duct, and the second air inlet shell is connected with the air outlet duct through the second air inlet duct; the motor is installed on the first air inlet shell, and the output shaft of the motor is coaxially connected with the centrifugal impeller; the second air inlet shell is in the shape of a plane perpendicular to the output shaft of the motor, the first air inlet shell is in the shape of a cone whose busbar forms an angle with the output shaft of the motor, and the outer diameter of the first air inlet shell gradually decreases in the direction away from the centrifugal impeller.

[0008] The double-sided suction centrifugal fan of the utility model, when in use, a motor drives the centrifugal impeller to rotate at a high speed, and external air is sucked into the first air inlet duct and the second air inlet duct from the first air inlet shell and the second air inlet shell respectively, and the air then flows out from the centrifugal impeller to the air outlet duct for discharge, wherein, the motor installation occupies a part of the air inlet area of ​​the first air inlet shell, so that the actual air inlet area of ​​the first air inlet shell is reduced, the first air inlet shell is designed to be conical, and the outer diameter size of the first air inlet shell gradually decreases in the direction away from the centrifugal impeller, that is, the first air inlet shell protrudes in the direction away from the wind wheel, thereby expanding the actual air inlet area of ​​the first air inlet shell, reducing the difference between the actual air inlet area of ​​the first air inlet shell and the air inlet area of ​​the second air inlet shell, and then reducing the difference in air intake volume on both sides of the centrifugal impeller, so that the load of the first air inlet duct at both ends of the centrifugal impeller is close to or even consistent, thereby reducing or even avoiding the risk of eccentric oscillation caused by uneven force on the centrifugal impeller, reducing noise, and reducing the dynamic balance and manufacturing accuracy requirements for the centrifugal impeller.

[0009] Furthermore, a mounting frame is provided on the inner side of the middle portion of the first air inlet shell, and the motor is mounted on the mounting frame.

[0010] Furthermore, the first air inlet shell is provided with a plurality of first ventilation slots, the second air inlet shell is provided with a plurality of second ventilation slots, and the difference between the sum of the areas of the plurality of first ventilation slots and the area of ​​the first ventilation slots covered by the orthographic projection of the mounting frame on the first air inlet shell is equal to the sum of the areas of the plurality of second ventilation slots.

[0011] Furthermore, the included angle between the busbar of the first air inlet housing and the output shaft of the motor is 80° to 85°.

[0012] Further, the centrifugal impeller includes a center disk, a plurality of first blades and a plurality of second blades, the plurality of first blades are evenly distributed on the periphery of one side of the center disk, the plurality of second blades are evenly distributed on the periphery of the other side of the center disk, two adjacent first blades are spaced apart, two adjacent second blades are spaced apart, the plurality of first blades and the center disk form the first air inlet duct, the plurality of second blades and the center disk form the second air inlet duct, and the output shaft of the motor is coaxially connected to the center disk.

[0013] Furthermore, it also includes a first front disk and a second front disk, the two ends of a plurality of the first blades are respectively connected to the central disk and the first front disk, and the two ends of a plurality of the second blades are respectively connected to the central disk and the second front disk.

[0014] The utility model also provides an air purifier, comprising a shell, a first filter assembly, a second filter assembly, a first air inlet grille, a second air inlet grille, an air outlet grille and the above-mentioned double-sided air suction centrifugal fan, the centrifugal fan being installed in the shell, and a first air suction port and a second air suction port are respectively provided on both sides of the shell, and the first air suction port is connected to the first air inlet duct through the first air inlet shell, and the second air suction port is connected to the second air inlet duct through the second air inlet shell, the first air inlet grille is installed on one side of the shell to install the first filter assembly in the first air suction port, the second air inlet grille is installed on the other side of the shell to install the second filter assembly in the second air suction port, and the air outlet grille is installed in the air outlet duct.

[0015] When the air purifier of the utility model is in use, a motor drives the centrifugal impeller to rotate at a high speed, and external air enters from the first air inlet grille and the second air inlet grille respectively, and is filtered by the first filter assembly and the second filter assembly respectively, and then enters the first air inlet duct and the second air inlet duct of the centrifugal impeller through the first air inlet shell and the second air inlet shell respectively. Under the action of centrifugal force, the air is thrown out from the centrifugal impeller to the air outlet duct and is discharged from the air outlet grille, thereby achieving air purification. In the utility model, since the first air inlet shell is in the shape of a cone with the busbar forming an angle with the output shaft of the motor, the air inlet area of ​​the first ventilation slot is larger than the air inlet area of ​​the second ventilation slot, and the excess part is offset by the area occupied by the installed motor, so that the air inlet areas on both sides of the centrifugal fan are adjusted to be basically consistent, thereby achieving the purpose of balancing the air intake volume at both ends of the centrifugal impeller, making the load of the first air inlet duct and the load of the second air inlet duct consistent, thereby avoiding the risk of eccentric oscillation caused by uneven force on the centrifugal impeller and reducing the manufacturing accuracy and dynamic balance requirements of the centrifugal impeller; at the same time, by balancing the air intake volume on both sides, it can ensure that the use and life of the first filter assembly and the second filter assembly on both sides are consistent, keep the purification performance on both sides of the air purifier consistent, and make the overall purification efficiency balanced and stable.

[0016] Furthermore, the first filter component includes a first primary filter and a first multi-effect composite filter, the first primary filter is located between the first air inlet grille and the first multi-effect composite filter, and the second filter component includes a second primary filter and a second multi-effect composite filter, the second primary filter is located between the second air inlet grille and the second multi-effect composite filter.

[0017] Furthermore, the first air suction port and the second air suction port are respectively provided with ultraviolet purification modules for sterilizing and disinfecting the flowing air.

[0018] Furthermore, an anti-leakage air outlet net is provided in the air outlet duct.

[0019] Compared with the background technology, the double-sided suction centrifugal fan and air purifier of the utility model have the following beneficial effects:

[0020] The air inlet areas on both sides of the centrifugal fan are adjusted to be basically the same, so as to achieve the purpose of balancing the air inlet volume at both ends of the centrifugal impeller, so that the load of the first air inlet duct is consistent with the load of the second air inlet duct, thereby avoiding the risk of eccentric vibration caused by uneven force on the centrifugal impeller and reducing the manufacturing accuracy and dynamic balance requirements for the centrifugal impeller;

[0021] By balancing the air intake on both sides, the usage and life of the first filter assembly and the second filter assembly on both sides can be guaranteed to be consistent, the purification performance on both sides of the air purifier can be kept consistent, and the overall purification efficiency can be balanced and stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of a double-sided suction centrifugal fan in an embodiment of the utility model;

[0023] Figure 2 for Figure 1 Sectional view of AA in the middle;

[0024] Figure 3 for Figure 2 A magnified view of the part B in the middle;

[0025] Figure 4 It is an exploded view of the air purifier in the embodiment of the utility model.

[0026] In the attached drawings: 1-volute; 11-first air inlet housing; 12-second air inlet housing; 13-mounting frame; 14-air outlet; 2-centrifugal impeller; 21-center disk; 22-first blade; 23-second blade; 24-first front disk; 25-second front disk; 3-motor; 4-housing; 5-first filter assembly; 51-first primary filter; 52-first multi-effect composite filter; 6 second filter assembly; 61-second primary filter; 62-second multi-effect composite filter; 7 first air inlet grille; 8 second air inlet grille; 9 air outlet grille; 10-leakage-proof air outlet net. DETAILED DESCRIPTION

[0027] The utility model is further described below in conjunction with specific implementation methods. The drawings are only used for exemplary descriptions, and are only schematic diagrams, not actual pictures, and cannot be understood as limitations on this patent; in order to better illustrate the embodiments of the utility model, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of the actual product; for those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0028] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, it is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0029] Embodiment 1

[0030] A double-sided suction centrifugal fan, such as Figures 1 to 3 As shown, it includes a volute 1, a centrifugal impeller 2 and a motor 3. The volute 1 is provided with a first air inlet shell 11 and a second air inlet shell 12 for air intake on both sides, and the volute 1 is provided with an air outlet 14 respectively connected with the first air inlet shell 11 and the second air inlet shell 12; the centrifugal impeller 2 is provided with a first air inlet duct and a second air inlet duct on both sides, the first air inlet shell 11 is connected with the air outlet duct 14 through the first air inlet duct, and the second air inlet shell 12 is connected with the air outlet duct 14 through the second air inlet duct; the motor 3 is installed on the first air inlet shell 11, and the output shaft of the motor 3 is coaxially connected with the centrifugal impeller 2; the second air inlet shell 12 is in a plane shape perpendicular to the output shaft of the motor 3, the first air inlet shell 11 is in a conical shape with a busbar forming an angle with the output shaft of the motor 3, and the outer diameter of the first air inlet shell 11 gradually decreases in the direction away from the centrifugal impeller 2.

[0031] When the double-sided suction centrifugal fan is in use, the motor 3 drives the centrifugal impeller 2 to rotate at a high speed, and the external air is sucked into the first air inlet duct and the second air inlet duct from the first air inlet shell 11 and the second air inlet shell 12 respectively, and the air then flows out from the centrifugal impeller 2 to the air outlet duct 14 for discharge, wherein the motor 3 is installed to occupy part of the air inlet area of ​​the first air inlet shell 11, so that the actual air inlet area of ​​the first air inlet shell 11 is reduced, and the first air inlet shell 11 is designed to be conical, and the outer diameter of the first air inlet shell 11 gradually decreases in the direction away from the centrifugal impeller 2. Small, that is, the first air inlet shell 11 protrudes away from the wind wheel, thereby expanding the actual air inlet area of ​​the first air inlet shell 11, reducing the difference between the actual air inlet area of ​​the first air inlet shell 11 and the air inlet area of ​​the second air inlet shell 12, and then reducing the difference in air intake volume on both sides of the centrifugal impeller 2, so that the load of the first air inlet duct at both ends of the centrifugal impeller 2 and the load of the second air inlet duct are close to or even consistent, thereby reducing or even avoiding the risk of eccentric oscillation caused by uneven force on the centrifugal impeller 2, reducing noise, and reducing the dynamic balance and manufacturing accuracy requirements of the centrifugal impeller 2.

[0032] like Figure 3 As shown, the angle between the busbar of the first air inlet housing 11 and the output shaft of the motor 3 is 80° to 85°. When the angle between the busbar of the first air inlet housing 11 and the output shaft of the motor 3 is adjusted to 80° to 85°, the air inlet areas on both sides of the centrifugal fan are basically the same, achieving the purpose of balancing the air inlet volume on both sides of the centrifugal impeller 2, making the loads at both ends of the centrifugal impeller 2 consistent, thereby avoiding the risk of eccentric oscillation caused by uneven force on the centrifugal impeller 2.

[0033] like Figure 3 As shown, the centrifugal impeller 2 includes a central disk 21, a plurality of first blades 22 and a plurality of second blades 23, the plurality of first blades 22 are evenly distributed around one side of the central disk 21, the plurality of second blades 23 are evenly distributed around the other side of the central disk 21, two adjacent first blades 22 are arranged at intervals, two adjacent second blades 23 are arranged at intervals, the plurality of first blades 22 and the central disk 21 form a first air inlet, the plurality of second blades 23 and the central disk 21 form a second air inlet, and the output shaft of the motor 3 is coaxially connected to the central disk 21. During implementation, the motor 3 drives the central disk 21 to rotate coaxially, thereby driving the plurality of first blades 22 and the plurality of second blades 23 to rotate at high speed, and the air in the first air inlet and the second air inlet is thrown out from the gaps between the first blades 22 and the gaps between the second blades 23 under the action of centrifugal force and discharged from the air outlet, so that the volute 1 forms a negative pressure, and the air is pressed into the first air inlet and the second air inlet through the first air inlet shell 11 and the second air inlet shell 12 respectively under the action of atmospheric pressure.

[0034] like Figure 3As shown, the centrifugal impeller 2 further includes a first front disk 24 and a second front disk 25, and the two ends of the first blades 22 are respectively connected to the center disk 21 and the first front disk 24, and the two ends of the second blades 23 are respectively connected to the center disk 21 and the second front disk 25. During implementation, the installation positions and gaps of the first blades 22 are fixed by the center disk 21 and the first front disk 24, and the installation positions and gaps of the second blades 23 are fixed by the center disk 21 and the second front disk 25, so as to ensure the stability of the centrifugal impeller 2 during high-speed rotation.

[0035] Embodiment 2

[0036] This embodiment is similar to the first embodiment, except that Figure 3 As shown, a mounting frame 13 is provided inside the middle of the first air inlet housing 11, and the motor 3 is mounted on the mounting frame 13. Due to the heavy weight of the motor 3, the plane structural strength of the upper volute 1 of the conventional centrifugal fan for mounting the motor 3 is relatively weak. In this embodiment, the first air inlet housing 11 is in a conical shape with a busbar and an output shaft of the motor 3 forming an angle, which can enhance the strength of the first air inlet housing 11. The motor 3 is then mounted by the mounting frame 13, which can improve the stability of the installation of the motor 3.

[0037] The first air inlet shell 11 is provided with a plurality of first ventilation slots, and the second air inlet shell 12 is provided with a plurality of second ventilation slots. The difference between the sum of the areas of the plurality of first ventilation slots and the area of ​​the first ventilation slots covered by the orthographic projection of the mounting frame 13 on the first air inlet shell 11 is equal to the sum of the areas of the plurality of second ventilation slots. In this embodiment, since the first air inlet shell 11 is in the shape of a cone whose busbar forms an angle with the output shaft of the motor 3, the air inlet area of ​​the first ventilation slot is larger than the air inlet area of ​​the second ventilation slot, and the excess part is offset by the area occupied by the motor 3, so that the air inlet areas on both sides of the centrifugal fan are adjusted to be basically consistent, achieving the purpose of balancing the air inlet volume at both ends of the centrifugal impeller 2, making the load of the first air inlet duct consistent with the load of the second air inlet duct, thereby avoiding the risk of eccentric vibration caused by uneven force on the centrifugal impeller 2 and reducing the noise value. At the same time, in this embodiment, only the structure of the first air inlet shell 11 needs to be designed, which reduces the manufacturing accuracy and dynamic balance requirements for the centrifugal impeller 2.

[0038] Embodiment 3

[0039] An air purifier, such as Figure 4As shown, it includes a shell 4, a first filter component 5, a second filter component 6, a first air inlet grille 7, a second air inlet grille 8, an air outlet grille 9 and the above-mentioned double-sided air suction centrifugal fan, the centrifugal fan is installed in the shell 4, and the first air suction port and the second air suction port are respectively provided on both sides of the shell 4, and the first air suction port is connected with the first air inlet duct through the first air inlet shell 11, and the second air suction port is connected with the second air inlet duct through the second air inlet shell 12, the first air inlet grille 7 is installed on one side of the shell 4 to install the first filter component 5 in the first air suction port, the second air inlet grille 8 is installed on the other side of the shell 4 to install the second filter component 6 in the second air suction port, and the air outlet grille 9 is installed in the air outlet duct 14.

[0040] When the above-mentioned air purifier is in use, the motor 3 drives the centrifugal impeller 2 to rotate at a high speed, and the external air enters from the first air inlet grille 7 and the second air inlet grille 8 respectively, and is filtered through the first filter component 5 and the second filter component 6 respectively, and then enters the first air inlet duct and the second air inlet duct of the centrifugal impeller 2 through the first air inlet shell 11 and the second air inlet shell 12 respectively. Under the action of centrifugal force, the air is thrown out from the centrifugal impeller 2 to the air outlet duct 14 and discharged from the air outlet grille 9, thereby achieving air purification. In the present embodiment, since the first air inlet shell 11 is in the shape of a cone with a busbar forming an angle with the output shaft of the motor 3, the air inlet area of ​​the first ventilation slot is larger than the air inlet area of ​​the second ventilation slot, and the excess part is offset by the area occupied by the installed motor 3, so that the air inlet areas on both sides of the centrifugal fan are adjusted to be basically consistent, thereby achieving the purpose of balancing the air inlet volume at both ends of the centrifugal impeller 2, making the load of the first air inlet duct and the load of the second air inlet duct consistent, thereby avoiding the risk of eccentric oscillation caused by uneven force on the centrifugal impeller 2, and reducing the manufacturing accuracy and dynamic balance requirements of the centrifugal impeller 2; at the same time, by balancing the air inlet volume on both sides, the usage and life of the first filter assembly 5 and the second filter assembly 6 on both sides can be guaranteed to be consistent, the purification performance on both sides of the air purifier is kept consistent, and the overall purification efficiency is balanced and stable.

[0041] like Figure 4 As shown, the first filter assembly 5 includes a first primary filter 51 and a first multi-effect composite filter 52, the first primary filter 51 is located between the first air inlet grille 7 and the first multi-effect composite filter 52, and the second filter assembly 6 includes a second primary filter 61 and a second multi-effect composite filter 62, the second primary filter 61 is located between the second air inlet grille 8 and the second multi-effect composite filter 62. The first primary filter 51 and the second primary filter 61 are used to intercept and filter large particles, and the first multi-effect composite filter 52 and the second multi-effect composite filter 62 are used to filter out small particles of dust and other impurities, and can effectively remove harmful gases such as odors in the air. By using the first primary filter 51 and the first multi-effect composite filter 52 in combination, and the second primary filter 61 and the second multi-effect composite filter 62 in combination, efficient purification of the air is achieved.

[0042] like Figure 4 As shown, a leak-proof outlet net 10 is provided in the air outlet duct 14. When air passes through the leak-proof outlet net 10 and is thrown out from the centrifugal impeller 2, the leak-proof outlet net 10 can prevent objects from falling into the air purifier.

[0043] The first air inlet and the second air inlet are respectively provided with ultraviolet purification modules for sterilizing and disinfecting the flowing air. The ultraviolet purification module may include a plurality of UVA patch lamps and UVC patch lamps to enhance the sterilization and disinfection effect of the ultraviolet purification module.

[0044] In the specific contents of the above-mentioned specific implementation methods, the various technical features can be combined in any non-contradictory manner. In order to make the description concise, not all possible combinations of the above-mentioned technical features are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0045] Obviously, the above embodiments of the utility model are only examples for clearly explaining the utility model, and are not intended to limit the implementation methods of the utility model. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made on the basis of the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the utility model should be included in the protection scope of the claims of the utility model.

Claims

1. A double-sided suction centrifugal fan, comprising a volute (1), a centrifugal impeller (2) and a motor (3), wherein a first air inlet shell (11) and a second air inlet shell (12) for air intake are respectively arranged on both sides of the volute (1), and the volute (1) is provided with an air outlet duct (14) respectively connected to the first air inlet shell (11) and the second air inlet shell (12); a first air inlet duct and a second air inlet duct are respectively arranged on both sides of the centrifugal impeller (2), the first air inlet shell (11) is connected to the air outlet duct (14) through the first air inlet duct, and the second air inlet shell (12) is connected to the air outlet duct (14) through the second air inlet duct; the motor (3) is mounted on the first air inlet shell (11), and the output shaft of the motor (3) is coaxially connected to the centrifugal impeller (2); characterized in that: The second air inlet housing (12) is in the shape of a plane perpendicular to the output shaft of the motor (3), the first air inlet housing (11) is in the shape of a cone whose generatrix forms an angle with the output shaft of the motor (3), and the outer diameter of the first air inlet housing (11) gradually decreases in a direction away from the centrifugal impeller (2).

2. The double-sided suction centrifugal fan according to claim 1, characterized in that: A mounting frame (13) is provided on the inner side of the middle portion of the first air inlet shell (11), and the motor (3) is mounted on the mounting frame (13).

3. The double-sided suction centrifugal fan according to claim 2, characterized in that: The first air inlet shell (11) is provided with a plurality of first ventilation slots, and the second air inlet shell (12) is provided with a plurality of second ventilation slots, and the difference between the sum of the areas of the plurality of first ventilation slots and the area of ​​the first ventilation slots covered by the orthographic projection of the mounting frame (13) on the first air inlet shell (11) is equal to the sum of the areas of the plurality of second ventilation slots.

4. The double-sided suction centrifugal fan according to claim 1, characterized in that: The included angle between the busbar of the first air inlet housing (11) and the output shaft of the motor (3) is 80° to 85°.

5. The double-sided suction centrifugal fan according to claim 1, characterized in that: The centrifugal impeller (2) comprises a central disk (21), a plurality of first blades (22) and a plurality of second blades (23); the plurality of first blades (22) are evenly distributed on the periphery of one side of the central disk (21); the plurality of second blades (23) are evenly distributed on the periphery of the other side of the central disk (21); two adjacent first blades (22) are arranged at intervals; two adjacent second blades (23) are arranged at intervals; the plurality of first blades (22) and the central disk (21) form the first air inlet duct; the plurality of second blades (23) and the central disk (21) form the second air inlet duct; and the output shaft of the motor (3) is coaxially connected to the central disk (21).

6. The double-sided suction centrifugal fan according to claim 5, characterized in that: It also includes a first front disk (24) and a second front disk (25), wherein two ends of a plurality of the first blades (22) are respectively connected to the central disk (21) and the first front disk (24), and two ends of a plurality of the second blades (23) are respectively connected to the central disk (21) and the second front disk (25).

7. An air purifier, characterized in that: The invention comprises a shell (4), a first filter assembly (5), a second filter assembly (6), a first air inlet grille (7), a second air inlet grille (8), an air outlet grille (9) and a double-sided air suction centrifugal fan as claimed in any one of claims 1 to 5, wherein the centrifugal fan is installed in the shell (4), and a first air suction port and a second air suction port are respectively provided on both sides of the shell (4), and the first air suction port is connected to the first air inlet duct through the first air inlet shell (11), and the second air suction port is connected to the second air inlet duct through the second air inlet shell (12), the first air inlet grille (7) is installed on one side of the shell (4) to install the first filter assembly (5) in the first air suction port, the second air inlet grille (8) is installed on the other side of the shell (4) to install the second filter assembly (6) in the second air suction port, and the air outlet grille (9) is installed in the air outlet duct (14).

8. The air purifier according to claim 7, characterized in that: The first filter assembly (5) comprises a first primary filter (51) and a first multi-effect composite filter (52), wherein the first primary filter (51) is located between the first air inlet grille (7) and the first multi-effect composite filter (52), and the second filter assembly (6) comprises a second primary filter (61) and a second multi-effect composite filter (62), wherein the second primary filter (61) is located between the second air inlet grille (8) and the second multi-effect composite filter (62).

9. The air purifier according to claim 8, characterized in that: The first air suction port and the second air suction port are respectively provided with ultraviolet purification modules for sterilizing and disinfecting the flowing air.

10. The air purifier according to claim 7, characterized in that: An anti-leakage air outlet net (10) is provided in the air outlet duct (14).

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