CN111197584A

CN111197584A - Centrifugal fan, air duct system and air conditioner

Info

Publication number: CN111197584A
Application number: CN201811389839.3A
Authority: CN
Inventors: 刘雷明; 邹云辉; 程春雨; 余明养; 孙小洪; 杨春霞; 郑海文; 王千千; 赵毓斌; 钱强; 陈珠秀; 陈荣华; 梁玉林; 陈诚
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2018-11-20
Filing date: 2018-11-20
Publication date: 2020-05-26
Also published as: WO2020103602A1; EP3855023B1; EP3855023A1

Abstract

The invention provides a centrifugal fan, an air duct system and an air conditioner, wherein the centrifugal fan comprises a volute main body and a centrifugal fan blade arranged in the volute main body, the volute main body comprises a bottom plate, a front plate and a side plate arranged between the bottom plate and the front plate, an air inlet of the centrifugal fan blade is arranged on the front plate, the side plate is provided with a volute tongue, the volute tongue inclines from one side of the bottom plate to one side of the front plate, so that the volute tongue gap is gradually reduced from one side of the bottom plate to one side of the front plate, thus the air flow at the outlet of the centrifugal fan blade is interfered with the static volute main body differently due to different space distances, different noise frequency spectrums are generated, the pneumatic noise of the centrifugal fan is effectively reduced, the howling caused by the resonance effect of the noise with the same frequency is avoided, and the tone quality, effectively reducing the total noise value of the centrifugal fan.

Description

Centrifugal fan, air duct system and air conditioner

Technical Field

The invention relates to the technical field of air conditioners, in particular to a centrifugal fan, an air duct system and an air conditioner.

Background

The centrifugal fan volute is used for concentrating and guiding gas from the impeller and converting partial kinetic energy diffusion of the gas into static pressure. When the impeller rotates, periodic collision between airflow brought by the impeller and the volute tongue and periodic passing through the minimum clearance between the blade and the volute tongue generate periodic rotating noise. The volute of the traditional centrifugal fan mostly adopts a straight volute tongue and a mode that the radius of the volute tongue is not changed, and the volute of the centrifugal fan used on an air conditioner has the following structure: the volute is internally provided with an impeller and comprises a front plate, side plates, a bottom plate and a volute tongue, wherein the front plate is provided with an air inlet, the bottom plate is opposite to the front plate, the axial lead of the impeller is perpendicular to the plane of the bottom plate, the longitudinal symmetry plane of the volute tongue is parallel to the axial lead of the impeller, and the longitudinal symmetry plane is a plane which bisects the volute tongue into two symmetrical parts along the direction from one end of the air inlet to one end of the bottom plate. The volute tongue clearance in the structure mode is that the minimum clearance between the outer circumference of the impeller, namely the blade top end and the volute tongue on the section perpendicular to the axial line of the impeller does not change along the axial direction of the impeller. Therefore, since the volute tongue clearance is equal in the entire axial direction, noises of the same frequency are superimposed to generate periodic peak noises, resulting in relatively high rotational noises of the centrifugal fan of this structure.

At present, the air conditioner using the centrifugal fan has two air outlets, the air outlet volume is large, the total air volume of the air conditioner is improved, and when the total air volume of the air conditioner is improved, the noise is correspondingly increased.

Disclosure of Invention

Therefore, the technical problem to be solved by the present invention is to overcome the defect of the prior art that the centrifugal fan has a relatively high noise, so as to provide a centrifugal fan with a relatively low noise, an air duct system and an air conditioner.

In order to solve the technical problem, the centrifugal fan provided by the invention comprises a volute main body and a centrifugal fan blade arranged in the volute main body, wherein the volute main body comprises a bottom plate, a front plate and a side plate arranged between the bottom plate and the front plate, an air inlet of the centrifugal fan blade is arranged on the front plate, the side plate is provided with a volute tongue, the volute tongue is inclined from one side of the bottom plate to one side of the front plate so that the volute tongue gap is gradually reduced from one side of the bottom plate to one side of the front plate, the volute tongue gap C at the front plate is smaller than the volute tongue gap D at the bottom plate, and the difference between the volute tongue gap D and the volute tongue gap C is E.

E is 4% -6% of the diameter of the impeller of the centrifugal fan blade.

The arc surface of the volute tongue is a conical arc, and the radius of the arc corresponding to the volute tongue gap at each position of the volute tongue is gradually reduced from one side of the bottom plate to one side of the front plate.

The radius of the volute tongue is 15-20 mm.

The side diffusion section of the centrifugal air duct of the centrifugal fan inclines from one side of the bottom plate to one side of the front plate, a tangent line which passes through the center of the centrifugal fan blade and is tangent to the arc-shaped section of the volute tongue, which is located at the bottom plate, is a first tangent line, a tangent line which passes through the center of the centrifugal fan blade and is tangent to the arc-shaped section of the volute tongue, which is located on the front plate, is a second tangent line, and an included angle formed by the projection of the first tangent line and the projection of the second tangent line on a plane perpendicular to the axial direction of the centrifugal fan blade is an inclination angle β.

7°≤β≤12°。

The opening degree of a volute of an air duct of the centrifugal fan is L5, the outlet distance of a diffusion section of the centrifugal air duct is L6, the ratio of L6 to L5 is M, and M is more than or equal to 2 and less than or equal to 3.

The present invention also provides an air duct system, comprising:

the air duct body comprises an air outlet at the side A and an air outlet at the side B;

the centrifugal fan is provided with a plurality of air duct bodies and is positioned between the air outlet at the side A and the air outlet at the side B, the centrifugal fan at least comprises a first centrifugal fan, the first centrifugal fan is provided with two first air ducts which are respectively communicated with the air outlet at the side A and the air duct at the side B, and the centrifugal fan adopts the centrifugal fan.

Centrifugal fan is provided with two, including one first centrifugal fan, a second centrifugal fan, second centrifugal fan has a second wind channel, the second centrifugal fan is close to A side setting, first centrifugal fan is close to B side setting, the second wind channel with A side air outlet intercommunication.

And a flow guide cavity is arranged on one side of the second centrifugal fan, and the flow guide cavity communicates the first A side air duct and the A side air outlet of the first centrifugal fan.

The volute body of the first centrifugal fan is aligned with the volute body of the second centrifugal fan.

The invention also provides an air conditioner which comprises the air duct system.

The technical scheme of the invention has the following advantages:

1. according to the centrifugal fan provided by the invention, the volute tongue clearance is gradually reduced from one side of the bottom plate to one side of the front plate, so that the air flow at the outlet of the centrifugal fan blade is interfered differently with the static volute main body due to different space distances, different noise frequency spectrums are generated, the pneumatic noise of the centrifugal fan is effectively reduced, the howling caused by the resonance action of the noise with the same frequency is avoided, the tone quality of the centrifugal fan is improved, and the total noise value of the centrifugal fan is effectively reduced.

2. According to the centrifugal fan provided by the invention, the side diffusion section surface of the centrifugal air duct of the centrifugal fan inclines from one side of the bottom plate to one side of the front plate, the tangent line which passes through the center of the centrifugal fan blade and is tangent to the arc-shaped section of the volute tongue at the bottom plate is a first tangent line, the tangent line which passes through the center of the centrifugal fan blade and is tangent to the arc-shaped section of the volute tongue at the front plate is a second tangent line, the included angle formed by the projection of the first tangent line and the projection of the second tangent line on the plane which is vertical to the axial direction of the centrifugal fan blade is an inclination angle β, and the side diffusion section surface inclines from one side of the bottom plate to one side of the front plate, so that the normal flow is prevented from being influenced by the vortex formed by airflow at the position.

3. According to the centrifugal fan provided by the invention, the opening degree of the volute of the air duct of the centrifugal fan is L5, the outlet distance of the diffusion section of the centrifugal air duct is L6, the ratio of L6 to L5 is M, and M is more than or equal to 2 and less than or equal to 3, so that the air output of the centrifugal fan can be ensured to reach an optimal value.

4. The invention provides an air duct system, comprising: the air duct body comprises an air outlet at the side A and an air outlet at the side B; the centrifugal fan is provided with a plurality of air duct bodies and is positioned between the air outlet at the side A and the air outlet at the side B, the centrifugal fan at least comprises a first centrifugal fan, the first centrifugal fan is provided with two first air ducts which are respectively communicated with the air outlet at the side A and the air duct at the side B, and the centrifugal fan adopts the centrifugal fan. Because the first centrifugal fan is provided with the two first air channels which are respectively a first A side air channel communicated with the A side air outlet of the air channel body and a first B side air channel communicated with the B side air outlet of the air channel body, the A side air outlet can suck the air out of the first A side air channel, the B side air outlet can suck the air out of the first B side air channel, the air outlet quantity of the A side air outlet is larger, the air outlet quantity of the B side air outlet is larger, the total air outlet quantity of the air channel system is larger, and because the centrifugal fan adopts the centrifugal fan, the noise of the centrifugal fan is smaller, the air channel system not only improves the total air outlet quantity, but also reduces the noise.

5. The air duct system provided by the invention has two centrifugal fans, wherein each centrifugal fan comprises a first centrifugal fan and a second centrifugal fan, the second centrifugal fan is provided with a second air duct, the second centrifugal fan is arranged close to the side A, the first centrifugal fan is arranged close to the side B, the second air duct is communicated with the side A air outlet, and the air outlet quantity of the side A air outlet of the air duct system is increased, so that the total air outlet quantity of the air duct system is increased.

6. According to the air duct system provided by the invention, one side of the second centrifugal fan is provided with the flow guide cavity, the flow guide cavity is used for communicating the first A side air duct of the first centrifugal fan with the A side air outlet, the air outlet of the second centrifugal fan can influence the pressure distribution in the flow guide cavity to form negative pressure, and the suction effect is formed on the air outlet of the first A side air duct of the first centrifugal fan, so that the air outlet quantity of the A side air outlet is increased.

7. According to the air duct system provided by the invention, the volute main body of the first centrifugal fan and the volute main body of the second centrifugal fan are arranged in an aligned manner, so that the air duct system is compact in structure and small in occupied volume.

8. The air conditioner provided by the invention comprises the air duct system, and the air conditioner is large in air outlet quantity and low in noise.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a front view of a duct system provided in embodiment 1 of the present invention;

FIG. 2 is a side view of one of the duct systems shown in FIG. 1;

FIG. 3 is a cross-sectional view of one of the duct systems shown in FIG. 1;

fig. 4 is a schematic structural view of a centrifugal fan provided in embodiment 1 of the present invention;

fig. 5 is a schematic structural view of a centrifugal fan provided in embodiment 1 of the present invention;

FIG. 6 is a front view of a duct system provided in embodiment 2 of the present invention;

FIG. 7 is a cross-sectional view of the side view of FIG. 6;

fig. 8 is a structural schematic view in a front view direction of the scroll structure provided in embodiment 4;

FIG. 9 is a rear view structural schematic of the volute configuration of FIG. 8;

fig. 10 is a sectional view of the centrifugal fan provided in example 4;

FIG. 11 is an exploded view of the centrifugal fan provided in example 4;

FIG. 12 is a cross-sectional view of a heat exchange fan assembly provided in example 5;

FIG. 13 is a cross-sectional view of a heat exchange fan assembly provided in example 5;

fig. 14 is a side view of a hot-exchange fan assembly provided in example 5.

Description of reference numerals:

100-bottom plate, 101-side plate, 102-fixed end, 103-containing cavity, 104-motor frame, 105-first arc-shaped reinforcing rib, 106-first connecting reinforcing rib, 107-connecting column, 108-second arc-shaped reinforcing rib, 109-second connecting reinforcing rib, 110-motor, 111-reinforcing block, 112-nut with pad, 113-volute main body, 200-centrifugal fan blade, 201-heat exchanger, 300-first centrifugal fan, 301-second centrifugal fan, 302-A side air outlet, 303-B side air outlet, 304-first A side air duct, 305-first B side air duct, 306-second air duct, 307-flow guide cavity, 308-front plate, 309-volute tongue, 310-side pressure expansion section surface, 311-first side plate and 312-second side plate.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

The present embodiment provides a centrifugal fan, including a volute body 113 and a centrifugal fan blade 200 disposed in the volute body 113, as shown in fig. 4 and 5, the volute body 113 includes a bottom plate 100, a front plate 308, and a side plate 101 disposed between the bottom plate 100 and the front plate 308, an air inlet of the centrifugal fan blade 200 is disposed on the front plate 308, the side plate 101 has a volute tongue 309, the volute tongue 309 is inclined from one side of the bottom plate 100 to one side of the front plate 308, so that a volute tongue gap gradually decreases from one side of the bottom plate 100 to one side of the front plate 308, a volute tongue gap C at the front plate 308 is smaller than a volute tongue gap D at the bottom plate 100, a difference between the volute tongue gap D and the volute tongue gap C is E, E is 4% -6% of a diameter of an impeller of the centrifugal fan blade 200, an arc surface of the volute tongue 309 adopts a conical arc, a radius of an arc corresponding to a circle corresponding to the arc from one side of the bottom plate 100 to one side of the front plate 308 is equal to or less than a tangent between a tangent line of a centrifugal fan blade 100 and a tangent line 9, a tangent line of a centrifugal fan blade exit of a centrifugal fan blade 9, a centrifugal fan blade 9 is equal to a tangent line, a tangent line of a centrifugal fan blade exit angle between a centrifugal fan blade 9 and a tangent line of a centrifugal fan blade 9, a centrifugal fan blade exit of a centrifugal fan duct tangent line 9, a centrifugal fan duct tangent line 9 mm, a centrifugal fan duct tangent line of a centrifugal fan duct tangent line 9, a centrifugal fan duct tangent line of a centrifugal fan duct tangent line of a centrifugal fan duct tangent duct 20-7, a centrifugal fan duct 20, a centrifugal fan duct.

Because the volute tongue clearance is gradually reduced from one side of the bottom plate 100 to one side of the front plate 308, the air flow at the outlet of the centrifugal fan blade 200 and the static volute main body 113 are interfered differently due to different space distances, and different noise frequency spectrums are generated, so that the aerodynamic noise of the centrifugal fan is effectively reduced, the howling caused by the resonance action of the noise with the same frequency is avoided, the tone quality of the centrifugal fan is improved, and the total noise value of the centrifugal fan is effectively reduced.

The embodiment also provides an air duct system, which comprises an air duct body and a plurality of centrifugal fans arranged on the body, wherein the centrifugal fans adopt the centrifugal fans. As shown in fig. 1 to fig. 3, the air duct body includes an a-side air outlet 302 and a B-side air outlet 303, where the a-side is an upper side and the B-side is a lower side in this embodiment. The centrifugal fans comprise a first centrifugal fan 300 and a second centrifugal fan 301, wherein the first centrifugal fan 300 is provided with two first air ducts, namely a first side-A air duct 304 communicated with the side-A air outlet 302 and a first side-B air duct 305 communicated with the side-B air outlet 303; the second centrifugal fan 301 is provided with a second air duct 306, the second centrifugal fan 301 is arranged close to the side A, the first centrifugal fan 300 is arranged close to the side B, and the second air duct 306 is communicated with the side A air outlet 302; a diversion cavity 307 is arranged on one side of the second centrifugal fan 301, and the diversion cavity 307 communicates the first a-side air duct 304 of the first centrifugal fan 300 with the a-side air outlet 302. As shown in fig. 2, the volute body 113 of the first centrifugal fan 300 is aligned with the volute body 113 of the second centrifugal fan 301.

Because the air outlet of the second centrifugal fan 301 at the side a air outlet 302 affects the pressure distribution in the guiding cavity 307 to form negative pressure, the suction effect is formed on the air outlet of the first side a air duct 304 of the first centrifugal fan 300, and thus the air outlet amount of the side a air outlet 302 can be increased. It is verified that, under the same condition, the first centrifugal fan 300 with the above form has two air channels, and compared with the prior art that the air volume of the first centrifugal fan 300 with only one air channel can be increased by 150m³/h—200m³And because the centrifugal fan adopts the centrifugal fan, the noise of the centrifugal fan is low, so that the air duct system not only improves the total air output, but also reduces the noise.

In an alternative embodiment, there are more than two centrifugal fans on the air duct body, and one or more of the centrifugal fans are set as the first centrifugal fan 300 having two air ducts.

Example 2

The present embodiment is different from the above embodiments in that side a is a lower side, and side B is an upper side, as shown in fig. 6 and 7, the first centrifugal fan 300 located on the upper side has two air ducts, which are respectively a first side a air duct 304 communicated with the side a air outlet 302 and a first side B air duct 305 communicated with the side B air outlet 303; the second centrifugal fan 301 on the lower side has a second air duct 306, and the second air duct 306 communicates with the a-side air outlet 302.

The first centrifugal fan 300 can simultaneously output air from the upper side and the lower side, the second centrifugal fan 301 can output air from the lower side, the total air output is improved, and meanwhile, the phenomenon that air flows are interfered with each other when the upper centrifugal fan and the lower centrifugal fan output air from the upper side and the lower side is avoided. When the air conditioner is used in the field of air conditioners, the lower air outlet volume ratio is large, so that the carpet type heating effect can be improved, hot air is prevented from being concentrated at the upper part of a room and is high, the comfort of a human body is improved, and better comfortable experience is provided for users; when the air duct system is used in the fields of freezing storage and the like, particularly when most of stored articles are positioned at the indoor bottom, the air duct system can be used for refrigerating working conditions, and the air outlet volume ratio is large, so that the gradual 'spreading type' refrigerating effect of indoor cold air from bottom to top can be greatly increased.

Example 3

The present embodiment provides an air conditioner having the duct system provided in embodiment 1 or embodiment 2. The air conditioner has the advantages of large air outlet volume and low noise.

Example 4

As shown in fig. 8 and 9, the volute structure provided by this embodiment includes a volute main body 113, where the volute main body 113 includes a bottom plate 100 and a side plate 101 disposed on the bottom plate 100, and a cavity 103 adapted to be installed on a fixed end 102 of a motor 110 and a connecting portion adapted to be connected to a motor frame 104 are disposed in an area on the bottom plate 100 and surrounded by the side plate 101.

In the volute structure of the embodiment, the motor mounting plate and the volute main body 113 are directly integrated into a whole, so that the development cost of an additional newly-opened mold is saved; the processes of manual transferring and screwing of newly added parts are omitted, and the assembly efficiency is improved; and motor mounting panel and the integrated back of spiral case main part 113 can not produce the abnormal sound problem that motor mounting panel and spiral case friction lead to, have improved and have been used for experience, improve the travelling comfort.

In order to ensure that the fixed end 102 of the motor is stably and reliably installed in the cavity 103, one end of the cavity 103 protrudes from the inner side wall of the bottom plate 100, and the bottom plate 100 is further provided with a first reinforcing structure for reinforcing the protruding end of the cavity 103.

Specifically, in this embodiment, it is preferable that the first reinforcing structure includes a first arc-shaped rib 105 disposed around the cavity 103, and a first connecting rib 106 having one end connected to a side wall of a protruding end of the cavity 103 and the other end connected to the first arc-shaped rib 105. Such a reinforcing structure can reliably reinforce the protruding end of the cavity 103 in four directions, i.e., front, back, left and right, and prevent the fixed end 102 from swinging in the cavity 103.

The connecting portion can be in various structures, in this embodiment, preferably, the connecting portion is a plurality of connecting posts 107 surrounding the cavity 103 and protruding from the inner side wall of the bottom plate 100, the connecting posts 107 are provided with threaded holes, and the connecting posts 107 are located on the outer side of the first circular arc-shaped rib 105. Four support legs of the motor frame 104 are respectively connected to the four connecting columns 107 through screws in a threaded manner.

Further, in order to ensure the stable and reliable connection between the motor frame 104 and the base plate, a second reinforcing structure for reinforcing the connecting column 107 is further arranged on the base plate 100.

Specifically, the second reinforcing structure includes:

a second arc-shaped reinforcing rib 108 concentrically arranged with the first arc-shaped reinforcing rib 105;

the second connecting reinforcing ribs 109 are arranged on two sides of the connecting column 107, one end of each second connecting reinforcing rib 109 on each side is connected with the first connecting reinforcing rib 106, and the other end of each second connecting reinforcing rib 109 is connected with the second connecting reinforcing rib 109;

and a plurality of third connecting reinforcing ribs are respectively connected between the connecting column 107 and the first circular-arc-shaped reinforcing ribs 105, between the connecting column 107 and the second circular-arc-shaped reinforcing ribs 108, and between the connecting column 107 and each side of the second connecting reinforcing ribs 109.

Such a reinforcing structure can reliably reinforce the connection column 107 in four directions, i.e., the front, the rear, the left and the right, and prevent the connection column 107 from shaking under the action of external force.

Further, the base plate comprises a plurality of reinforcing blocks 111 which surround the second arc-shaped reinforcing ribs 108 and are arranged on the base plate 100 at intervals. The reinforcing block 111 is provided to reinforce the base plate 100.

Preferably, one side of the reinforcing block 111 is connected with the outer wall of the second circular arc-shaped reinforcing rib 108, so that the reinforcing block 111 can also reinforce the second circular arc-shaped reinforcing rib 108 at the same time, and the stability and reliability of the connecting column are further ensured.

As shown in fig. 10 and 11, the centrifugal fan of this embodiment includes a centrifugal fan blade 200, a motor 110, a motor frame 104, and a volute structure as described above, a fixed end 102 of the motor 110 is installed in the cavity 103, an output shaft of the motor 110 passes through the motor frame 104 to be connected with the centrifugal fan blade 200, and the motor frame 104 is connected with the connecting portion to fix the motor 110 on the volute structure. The centrifugal fan of this embodiment is because of having foretell spiral case structure, consequently, has avoided the production of abnormal sound, and user experience is good, and the travelling comfort is good.

An air conditioner of this embodiment has the centrifugal fan as described above. Not only avoids the generation of abnormal sound and has good comfort, but also has low development cost.

The assembling process of the centrifugal fan of the embodiment:

the fixed end 102 provided with the vibration damping rubber of the motor 110 is arranged in the cavity 103 on the volute structure, then the through hole on the motor frame 104 penetrates through the output shaft of the motor 110 and is fixedly connected to the bottom plate 100 of the volute structure, so that the fixed end 102 is tightly pressed with the cavity 103, and the motor 110 is locked. The centrifugal fan blade 200 is mounted on the output shaft of the motor 110, and finally the output shaft of the motor 110 is screwed in by the nut 112 with the gasket to lock the centrifugal fan blade 200.

Example 5

As shown in fig. 12-14, the heat exchanger assembly is a specific embodiment of a heat exchanger fan assembly, and includes a centrifugal fan and a heat exchanger 201, where the centrifugal fan includes a centrifugal fan blade 200, the diameter of the centrifugal fan blade 200 is L2, the heat exchanger 201 is disposed on an air inlet side of the centrifugal fan, the width of the heat exchanger 201 is L1, in order to ensure that the heat exchanger 201 is completely located in a flow field driven by the centrifugal fan blade 200, and it is necessary to satisfy L2 ≥ L1, the ratio of the width of the heat exchanger 201 to the diameter of the centrifugal fan blade 200 is F, in order to ensure a heat exchange area of the heat exchanger 201, in this embodiment, 0.8 ≤ F1, in order to increase a contact area between the heat exchanger 201 and air, the heat exchanger 201 employs a bent heat exchanger, the face of the heat exchanger 201 close to the centrifugal fan blade 200 is a concave face, the width L1 of the heat exchanger 201 refers to a distance between two end points of the concave faces of the concave face of the heat exchanger 201 in a direction parallel to the end faces of the centrifugal fan blade 200, the concave face of the heat exchanger 201 is equal to the concave face of the centrifugal fan blade 200, the concave face of the heat exchanger 201 is equal to 6326, the concave face of the heat exchanger 201, the concave face of the heat exchanger 201 is equal to or less than equal to or less than equal to.

Specifically, when the centrifugal fan works, air enters between the heat exchanger 201 and the centrifugal fan blades 200, is absorbed by the centrifugal fan after heat exchange is carried out by the heat exchanger 201, and is discharged from the upper end of the centrifugal fan. Because the ratio of the width of the heat exchanger 201 to the diameter of the centrifugal fan blade 200 satisfies 0.8 and F is less than or equal to 1, and the ratio of L2 to L3 satisfies 1.5 and G is less than or equal to 1.77, the centrifugal fan and the heat exchanger 201 cooperate to form an optimal wind field, so that the air and the heat exchanger 201 exchange heat uniformly, and the capacity of the heat exchanger 201 is fully exerted.

In an alternative embodiment, the heat exchanger 201 does not adopt a bent heat exchanger, and the width of the heat exchanger 201 refers to the distance between two end points of the heat exchanger 201 close to the centrifugal fan blade 200 in a direction parallel to the end of the centrifugal fan blade 200.

The embodiment further provides an air conditioner, which comprises the heat exchange fan assembly, and the heat exchange performance of the heat exchanger 201 is better, so that the performance of the air conditioner is better.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. A centrifugal fan is characterized by comprising a volute main body (113) and centrifugal fan blades (200) arranged in the volute main body (113), the volute body (113) comprises a bottom plate (100), a front plate (308), and a side plate (101) arranged between the bottom plate (100) and the front plate (308), the air inlet of the centrifugal fan blade (200) is arranged on the front plate (308), the side plate (101) is provided with a volute tongue (309), the volute tongue (309) inclines from one side of the bottom plate (100) to one side of the front plate (308), so that the volute tongue clearance is gradually reduced from one side of the bottom plate (100) to one side of the front plate (308), the volute tongue clearance C at the front plate (308) is smaller than the volute tongue clearance D at the bottom plate (100), and the difference between the volute tongue clearance D and the volute tongue clearance C is E.

2. A centrifugal fan according to claim 1, wherein E is 4-6% of the diameter of the impeller of the centrifugal fan blade (200).

3. The centrifugal fan as claimed in claim 2, wherein the arc surface of the volute tongue (309) is a conical arc, and the radius of the arc corresponding to each volute tongue gap of the volute tongue (309) is gradually reduced from one side of the bottom plate (100) to one side of the front plate (308).

4. A centrifugal fan according to claim 3, wherein the radius of the volute tongue (309) is 15-20 mm.

5. The centrifugal fan according to claim 3, wherein the side diffuser (310) of the centrifugal air duct of the centrifugal fan is inclined from one side of the bottom plate (100) to one side of the front plate (308), a tangent line passing through the center of the centrifugal fan (200) and tangent to the arc-shaped section of the volute tongue (309) located at the bottom plate (100) is a first tangent line, a tangent line passing through the center of the centrifugal fan (200) and tangent to the arc-shaped section of the volute tongue (309) located at the front plate (308) is a second tangent line, and a projection of the first tangent line and the projection of the second tangent line on a plane perpendicular to the axial direction of the centrifugal fan (200) form an included angle of β.

6. A centrifugal fan according to claim 5, characterized in that 7 ° ≦ β ≦ 12 °.

7. The centrifugal fan as claimed in claim 6, wherein the opening of the volute of the air duct of the centrifugal fan is L5, the outlet distance of the diffuser section of the centrifugal fan is L6, the ratio of L6 to L5 is M, and M is 2-3.

8. An air duct system, comprising:

the air duct body comprises an A-side air outlet (302) and a B-side air outlet (303);

the centrifugal fan is arranged on the air duct body in a plurality of positions between the air outlet (302) at the side A and the air outlet (303) at the side B, the centrifugal fan at least comprises a first centrifugal fan (300), the first centrifugal fan (300) is provided with two first air ducts, namely a first air duct (304) at the side A communicated with the air outlet (302) at the side A and a first air duct (305) at the side B communicated with the air outlet (303) at the side B, and the centrifugal fan adopts the centrifugal fan in any one of claims 1-7.

9. An air duct system according to claim 8, wherein there are two centrifugal fans, including a first centrifugal fan (300) and a second centrifugal fan (301), the second centrifugal fan (301) has a second air duct (306), the second centrifugal fan (301) is disposed near the side a, the first centrifugal fan (300) is disposed near the side B, and the second air duct (306) is communicated with the side a air outlet (302).

10. An air duct system according to claim 9,

a flow guide cavity (307) is formed in one side of the second centrifugal fan (301), and the first A-side air duct (304) of the first centrifugal fan (300) is communicated with the A-side air outlet (302) through the flow guide cavity (307).

11. An air duct system according to claim 10,

the volute body (113) of the first centrifugal fan (300) is aligned with the volute body (113) of the second centrifugal fan (301).

12. An air conditioner comprising a duct system according to any one of claims 8 to 11.