WO2020103602A1

WO2020103602A1 - Centrifugal fan, air duct system, and air conditioner

Info

Publication number: WO2020103602A1
Application number: PCT/CN2019/110757
Authority: WO
Inventors: 刘雷明; 邹云辉; 程春雨; 余明养; 孙小洪
Original assignee: 珠海格力电器股份有限公司
Priority date: 2018-11-20
Filing date: 2019-10-12
Publication date: 2020-05-28
Also published as: CN111197584A; EP3855023B1; EP3855023A1

Abstract

A centrifugal fan, an air duct system, and an air conditioner. The centrifugal fan comprises a volute casing body (113) and centrifugal fan blades (200) disposed in the volute casing body (113). The volute casing body (113) comprises a bottom plate (100), a front plate (308), and a side plate (101) between the bottom plate (100) and the front plate (308). The air inlet of the centrifugal fan blades (200) is disposed on the front plate (308). A volute tongue (309) is disposed on the side plate (101). The volute tongue (309) is inclined from one side of the bottom plate (100) toward one side of the front plate (308), so that a volute tongue clearance is gradually reduced from one side of the bottom plate (100) toward one side of the front plate (308). Due to different space distances, the interference between the airflow at the exit of the centrifugal fan blades (200) and the stationary volute casing body (113) is different, resulting in different noise spectra, thereby reducing the noise of the centrifugal fan, avoiding howling caused by the noise having the same frequency due to resonance, and improving the sound quality of the centrifugal fan.

Description

Centrifugal fan, air duct system and air conditioner

Cross-reference of related applications

This application requires the priority of the Chinese patent application entitled "A Centrifugal Fan, Air Duct System, and Air Conditioner" filed on November 20, 2018, with the application number 201811389839.3, and the full text of which is hereby incorporated as reference.

Technical field

This application relates to the technical field of air conditioning, and in particular to a centrifugal fan, air duct system and air conditioner.

Background technique

The role of the centrifugal fan volute is to concentrate and divert the gas from the impeller, and convert part of the kinetic energy of the gas into a static pressure. When the impeller rotates, the periodic collision between the air flow brought by the impeller and the volute and the air flow periodically passing through the minimum gap between the blade and the volute will produce a periodic rotation noise. Traditional centrifugal fan volutes mostly adopt the form of a straight volute tongue with a constant radius of the volute tongue. For example, the volute of a centrifugal fan used in an air conditioner has such a structure: an impeller is provided in the volute, and the volute includes a front plate and side plates , The bottom plate and the volute tongue, the front plate is provided with an air inlet, the bottom plate is opposed to the front plate, the impeller axis is perpendicular to the plane of the bottom plate, the longitudinal symmetry plane of the volute tongue is parallel to the impeller axis, the longitudinal symmetry plane refers to the The tongue is divided into two symmetrical planes in the direction from the end of the air inlet to the end of the bottom plate. The volute gap of this structure, that is, the minimum gap between the outer circumference of the impeller, that is, the tip of the blade and the volute, does not change along the axis of the impeller in a section perpendicular to the axis of the impeller. Therefore, since the volute gap is equal in the entire axis direction, the noise of the same frequency is superimposed, resulting in periodic peak noise, resulting in relatively high rotational noise of the centrifugal fan of this structure.

At present, for air conditioners using centrifugal fans, some centrifugal fans have two air outlets. The larger the air output, the total air volume of the air conditioner is increased. However, while the total air volume of the air conditioner is increased, the noise will increase accordingly.

Summary of the invention

Therefore, the technical problem to be solved by the present application is to overcome the defects of the centrifugal fan in the prior art that the noise is large, thereby providing a centrifugal fan, an air duct system and an air conditioner with low noise.

To solve the above technical problems, a centrifugal fan provided by the present application includes a volute body, a centrifugal fan blade disposed in the volute body, the volute body includes a bottom plate, a front plate, and a bottom plate The side plate between the front plate and the air inlet of the centrifugal fan blade is provided on the front plate, the side plate has a volute tongue, and the volute tongue faces the side from the side of the bottom plate The side of the front plate is inclined so that the volute gap gradually decreases from the side of the bottom plate toward the side of the front plate, and the volute gap C at the front plate is smaller than the volute gap at the bottom plate D, and the difference between the volute gap D and the volute 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 adopts a conical arc, and the radius of the arc corresponding to each volute gap of the volute tongue gradually decreases from the side of the bottom plate to the side of the front plate.

The radius of the volute is 15-20mm.

The side diffuser section surface of the centrifugal air duct of the centrifugal fan is inclined from the side of the bottom plate toward the side of the front plate, passes through the center of the centrifugal fan blade, and is located on the The tangent line of the arc segment at the bottom plate is the first tangent line, passing through the center of the centrifugal fan blade, and the tangent line tangent to the arc segment of the volute located on the front plate is the second tangent line , The angle formed by the projection of the first tangent line and 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 volute opening of the air duct of the centrifugal fan is L5, the outlet distance of the expansion section of the centrifugal air duct is L6, the ratio of L6 and L5 is M, and 2≤M≤3.

This application also provides an air duct system, including:

The air duct body, including the air outlet on the A side and the air outlet on the B side;

A centrifugal fan is provided on the air duct body and is located between the A-side air outlet and the B-side air outlet. The centrifugal fan includes at least one first centrifugal fan, the first The centrifugal fan has two first air ducts, which are the first A-side air duct communicating with the A-side air outlet and the first B-side air duct communicating with the B-side air outlet. The centrifugal fan adopts the above Of a centrifugal fan.

Two centrifugal fans are provided, including one first centrifugal fan and one second centrifugal fan. The second centrifugal fan has a second air channel, and the second centrifugal fan is disposed near the A side. The first centrifugal fan is disposed near the B side, and the second air passage communicates with the A side air outlet.

A guide cavity is provided on one side of the second centrifugal fan, and the guide cavity connects the first A-side air duct of the first centrifugal fan and the A-side air outlet.

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

The present application also provides an air conditioner, including the above-mentioned air duct system.

The technical solution of this application has the following advantages:

1. A centrifugal fan provided by the present application, because the volute gap gradually decreases from the side of the bottom plate to the side of the front plate, such that the air flow and the static The interference between the main body of the volute produces different noise spectrum, which effectively reduces the aerodynamic noise of the centrifugal fan, avoids the howling noise caused by the resonance of the same frequency noise, improves the sound quality of the centrifugal fan, and effectively reduces The total noise of the centrifugal fan.

2. A centrifugal fan provided by the present application, the side diffuser section surface of the centrifugal air duct of the centrifugal fan is inclined from one side of the bottom plate toward one side of the front plate, passing through the center of the centrifugal fan blade , And the tangent line that is tangent to the arc-shaped section of the volute located at the bottom plate is the first tangent line, passing through the center of the centrifugal fan blade, and the tang of the volute located on the front plate The tangent line of the arc-shaped section is a second tangent line, and the angle formed by the projection of the first tangent line and the second tangent line on the plane perpendicular to the axial direction of the centrifugal fan blade is the inclination angle β , The side diffuser section surface is inclined from the side of the bottom plate toward the side of the front plate, so that the arrangement can prevent the air flow from forming a vortex at this position and affecting the normal flow.

3. A centrifugal fan provided by the present application, the volute opening of the air duct of the centrifugal fan is L5, the exit distance of the expansion section of the centrifugal air duct is L6, the ratio of L6 and L5 is M, and 2≤M ≤3, this setting can ensure that the air output of the centrifugal fan reaches the optimal value.

4. An air duct system provided by the present application, comprising: an air duct body including an air outlet on the A side and an air outlet on the B side; a centrifugal fan provided with a plurality of air duct bodies and located on the A Between the side air outlet and the B-side air outlet, the centrifugal fan includes at least one first centrifugal fan, and the first centrifugal fan has two first air passages, which are respectively in communication with the A-side air outlet The first A-side air duct, and the first B-side air duct communicating with the B-side air outlet, the centrifugal fan adopts the above-mentioned centrifugal fan. Since the first centrifugal fan has two first air ducts, they are the first A-side air duct communicating with the A-side air outlet of the air duct body, and the first B-side air duct communicating with the B-side air outlet of the air duct body , The A-side air outlet will have a suction effect on the first A-side air duct, the B-side air outlet will have a suction effect on the first B-side air duct, and the A-side air outlet has a larger air volume , The air output of the air outlet on the B side is large, the total air output of the air duct system is large, and because the centrifugal fan adopts one of the above centrifugal fans, the noise of the centrifugal fan is small, so the air duct system has increased the total The air output reduces the noise again.

5. An air duct system provided by the present application, two centrifugal fans are provided, including one first centrifugal fan and one second centrifugal fan, and the second centrifugal fan has one second air duct. The second centrifugal fan is located near the A side, the first centrifugal fan is located near the B side, the second air duct communicates with the air outlet on the A side, and the air output of the air outlet on the A side of the air duct system increases, thereby Increased the total air output of the air duct system.

6. An air duct system provided by the present application, a guide cavity is provided on one side of the second centrifugal fan, the guide cavity connects the first A-side air duct of the first centrifugal fan The air outlet on the A side is connected. The air outlet of the second centrifugal fan will affect the pressure distribution in the deflector cavity and form a negative pressure, which will form a suction effect on the air outlet of the first A side air duct of the first centrifugal fan. Therefore, the air output of the air outlet on the A side is increased.

7. An air duct system provided by the present application, wherein the volute body of the first centrifugal fan is aligned with the volute body of the second centrifugal fan. The air duct system has a compact structure and a small footprint.

8. An air conditioner provided by the present application includes the above-mentioned air duct system, the air output of the air conditioner is large, and the noise is small.

BRIEF DESCRIPTION

In order to more clearly explain the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings required for the specific embodiments or the description of the prior art. The drawings are some embodiments of the present application. For those of ordinary skill in the art, without paying any creative labor, other drawings can also be obtained based on these drawings.

1 is a front view of an air duct system provided in Example 1 of this application;

2 is a side view of the air duct system shown in FIG. 1;

3 is a cross-sectional view of an air duct system shown in FIG. 1;

4 is a schematic structural diagram of a centrifugal fan provided in Example 1 of this application;

5 is a schematic structural diagram of a centrifugal fan provided in Example 1 of this application;

6 is a front view of an air duct system provided in Example 2 of this application;

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

8 is a schematic structural view of the front view direction of the volute structure provided in Example 4;

9 is a schematic structural view of the volute structure of FIG. 8 in a rear view direction;

10 is a cross-sectional view of the centrifugal fan provided in Example 4;

11 is an exploded view of the centrifugal fan provided in Example 4;

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

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

14 is a side view of a heat exchange fan assembly provided in Example 5. FIG.

Description of reference signs:

100-base plate, 101-side plate, 102-fixed end, 103-cavity, 104-motor frame, 105-first arc-shaped reinforcing rib, 106-first connecting rib, 107-connecting column, 108-section Two arc-shaped reinforcing ribs, 109-second connecting ribs, 110-motor, 111-reinforced block, 112-nut with packing, 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-diversion cavity, 308-front plate, 309-volute tongue, 310-side diffuser section surface, 311-first side plate, 312-second side plate.

detailed description

The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, but not all of them. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

In the description of this application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, with a specific orientation The construction and operation cannot therefore be understood as a limitation of this application. In addition, the terms "first", "second", and "third" are for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense, for example, it can be fixed connection or detachable Connected, or connected integrally; either mechanically or electrically; directly connected, or indirectly connected through an intermediary, or internally connected between two components. For those of ordinary skill in the art, the specific meaning of the above terms in this application can be understood in specific situations.

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

Example 1

This 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 FIGS. 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, and the air inlet of the centrifugal fan blade 200 Set on the front plate 308, the side plate 101 has a volute tongue 309, the volute tongue 309 is inclined from the side of the bottom plate 100 toward the side of the front plate 308, so that the volute tongue gap The side of the bottom plate 100 gradually decreases toward the side of the front plate 308, the volute gap C at the front plate 308 is smaller than the volute gap D at the bottom plate 100, and the volute gap D The difference from the volute gap C is E, which is 4% -6% of the diameter of the impeller of the centrifugal fan blade 200. The arc surface of the volute tongue 309 adopts a conical arc, and the radius of the arc corresponding to each volute gap of the volute tongue 309 is pressed from the side of the bottom plate 100 to the side of the front plate 308 The linear law gradually decreases, and the radius of the volute tongue 309 is 15-20 mm. The side diffuser section surface 310 of the centrifugal air duct of the centrifugal fan is inclined from the side of the bottom plate 100 toward the side of the front plate 308, passes through the center of the centrifugal fan blade 200, and is in contact with the volute tongue The tangent line of the arc section of 309 located at the bottom plate 100 is the first tangent line, passes through the center of the centrifugal fan blade 200, and is the arc shape of the volute 309 on the front plate 308 The tangent line of the tangent segment is the second tangent line, and the angle formed by the projection of the first tangent line and the second tangent line on the plane perpendicular to the axial direction of the centrifugal fan blade 200 is the inclination angle β, Among them, 7 ° ≤β≤12 °. The side plate 101 in this embodiment includes a vertical first side plate 311 and a second side plate 312 inclined with respect to the first side plate 311, the volute of the air duct of the centrifugal fan has an opening degree of L5 , The volute opening degree is the minimum distance from the centrifugal wind wheel to the first side plate 311, the exit distance of the centrifugal air duct diffuser section is L6, and the centrifugal air duct diffuser section exit distance refers to the The minimum distance between the volute tongue 309 and the second side plate 312, the ratio of L6 to L5 is M, and 2≤M≤3. Since the volute gap gradually decreases from the side of the bottom plate 100 toward the side of the front plate 308, the air flow at the outlet of the centrifugal fan blade 200 and the stationary volute body 113 interfere differently due to different spatial distances , Generate different noise spectrum, which effectively reduces the aerodynamic noise of the centrifugal fan, avoids the howling noise caused by the same frequency noise due to resonance, improves the sound quality of the centrifugal fan, and effectively reduces the total noise value of the centrifugal fan.

This embodiment also provides an air duct system, including an air duct body and a plurality of centrifugal fans provided on the body, the centrifugal fan adopts the above-mentioned centrifugal fan. As shown in FIGS. 1-3, the air duct body includes an A-side air outlet 302 and a B-side air outlet 303. In this embodiment, the A side is the upper side and the B side is the lower side. The centrifugal fan includes a first centrifugal fan 300 and a second centrifugal fan 301. The first centrifugal fan 300 has two first air ducts, which are respectively the first A-side air ducts communicating with the A-side air outlet 302 304, a first B-side air duct 305 communicating with the B-side air outlet 303; the second centrifugal fan 301 has a second air duct 306, the second centrifugal fan 301 is disposed near the A side, and the first A centrifugal fan 300 is disposed near the B side, and the second air duct 306 communicates with the air outlet 302 on the A side; a guide cavity 307 is provided on one side of the second centrifugal fan 301, and the guide cavity 307 will The first A-side air duct 304 of the first centrifugal fan 300 communicates 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.

Since the air outlet of the second centrifugal fan 301 at the A-side air outlet 302 will affect the pressure distribution in the deflector cavity 307, a negative pressure is formed, which will cause the air outlet of the first A-side air duct 304 of the first centrifugal fan 300 The suction effect can increase the air output of the A-side air outlet 302. It has been verified that under the same conditions, the first centrifugal fan 300 of this form has two air channels. Compared with the prior art, the first centrifugal fan 300 has only one air channel, the air volume can be increased by 150m ³ / h—200m ³ / h, and because the centrifugal fan uses the above-mentioned centrifugal fan, the noise of the centrifugal fan is small, so the air duct system not only increases 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 centrifugal fans are set as the first centrifugal fan 300 with two air ducts.

Example 2

The difference between this embodiment and the above embodiment is that the A side is the lower side and the B side is the upper side. As shown in FIGS. 6 and 7, the first centrifugal fan 300 on the upper side has two air passages, respectively The first A-side air duct 304 communicating with the A-side air outlet 302, the first B-side air duct 305 communicating with the B-side air outlet 303; the second centrifugal fan 301 located on the lower side has a second air duct 306 The second air channel 306 communicates with the air outlet 302 on the A side.

The first centrifugal fan 300 can emit air up and down at the same time, and the second centrifugal fan 301 can emit air downward, which improves the total air output, and at the same time avoids the phenomenon that the air flow interferes with each other when the upper and lower centrifugal fans are both on the upper and lower sides . When it is used in the air-conditioning field, under heating conditions, the lower outflow air volume accounts for a larger amount, which can improve the "carpet-type" heating effect, avoiding the concentration of hot air above the indoor level, increasing human comfort, giving users a better Comfortable experience; when used in the field of freezing storage, especially when the storage items are mostly at the bottom of the room, this air duct system can be used for cooling conditions, and the proportion of the outflow air volume can greatly increase the indoor cold air The cooling effect is gradually increased from bottom to top.

Example 3

This embodiment provides an air conditioner having the air duct system provided in Embodiment 1 or Embodiment 2. The air output of the air conditioner is large, and the noise is small.

Example 4

As shown in FIGS. 8 and 9, a volute structure provided in this embodiment includes a volute body 113. The volute body 113 includes a bottom plate 100 and a side plate 101 disposed on the bottom plate 100. A cavity 103 suitable for mounting the fixed end 102 of the motor 110 and a connecting portion suitable for connecting to the motor frame 104 are provided on the bottom plate 100 in an area enclosed by the side plate 101.

The volute structure of this embodiment directly integrates the motor mounting plate with the volute body 113, which not only saves the development cost of additional newly developed molds; it also saves the manual transfer of newly added parts and the process of screwing, Improve the assembly efficiency; and after the motor mounting plate is integrated with the volute body 113, there will be no abnormal noise caused by the friction between the motor mounting plate and the volute, which improves the experience and improves the 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 also provided with a The first reinforced structure where the protruding end is reinforced.

Specifically, in this embodiment, it is preferable that the first reinforcing structure includes a first arc-shaped stiffener 105 disposed around the cavity 103, and one end is connected to the side wall of the protruding end of the cavity 103, The first connection stiffener 106 connected to the first arc-shaped stiffener 105 at the other end. Such a reinforcement structure can reliably reinforce the protruding ends of the cavity 103 in four directions of front, back, left, and right, and prevent the fixed end 102 from shaking in the cavity 103.

The connecting portion may have various structures. In this embodiment, the connecting portion preferably includes a plurality of connecting posts 107 that surround the cavity 103 and protrude from the inner side wall of the bottom plate 100. The connecting post 107 is provided with a threaded hole, and the connecting post 107 is outside the first arc-shaped reinforcement 105. The four legs of the electrical frame 104 are screwed to the four connecting posts 107 through screws, respectively.

Further, in order to ensure a stable and reliable connection between the motor frame 104 and the bottom plate, the bottom plate 100 is also provided with a second reinforcement structure that reinforces the connection column 107.

Specifically, the second reinforcement structure includes:

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

The second connection reinforcement 109 is provided on both sides of the connection column 107, and one end of the second connection reinforcement 109 on each side is connected to the first connection reinforcement 106, and the other end is connected to the first Two connection reinforcement 109 connection;

The third connection reinforcement rib is provided with a plurality of connection ribs connected between the connection post 107 and the first arc-shaped reinforcement 105, and between the connection post 107 and the second arc-shaped reinforcement rib 108, respectively Between the connecting post 107 and the second connecting reinforcement 109 on each side.

Such a reinforcement structure can reliably reinforce the connecting post 107 in four directions of front, back, left, and right, and prevent the connecting post 107 from shaking under external force.

Further, a plurality of reinforcing blocks 111 surrounding the second arc-shaped reinforcing ribs 108 and spaced on the bottom plate 100 are also included. The reinforcement block 111 can reinforce the bottom plate 100.

Preferably, one side of the reinforcing block 111 is connected to the outer wall of the second arc-shaped reinforcing rib 108, so that the reinforcing block 111 can simultaneously reinforce the second arc-shaped reinforcing rib 108, thereby ensuring the stability of the connecting column reliability.

As shown in FIGS. 10 and 11, a centrifugal fan in this embodiment includes a centrifugal fan blade 200, a motor 110, and a motor frame 104, and further includes a volute structure as described above, and the fixed end 102 of the motor 110 Installed in the cavity 103, the output shaft of the motor 110 is connected to the centrifugal fan blade 200 through the motor frame 104, and the motor frame 104 is connected to the connecting portion to fix the motor 110 at The volute structure. Since the centrifugal fan of this embodiment has the above-mentioned volute structure, the generation of abnormal noise is avoided, and the user experience is good and the comfort is good.

An air conditioner of this embodiment has the centrifugal fan as described above. Not only does it avoid the occurrence of abnormal sounds, it has good comfort, but also has low development costs.

The assembly process of the centrifugal fan in this embodiment:

Install the fixed end 102 of the motor 110 provided with vibration-damping rubber into the cavity 103 on the volute structure, and then pass the through hole on the motor frame 104 through the output shaft of the motor 110 and fixedly connect to the bottom plate of the volute structure At 100, the fixed end 102 and the cavity 103 are compressed, and the motor 110 is locked since then. Install the centrifugal fan blade 200 on the output shaft of the motor 110, and finally screw in the output shaft of the motor 110 with a nut 112 to lock the centrifugal fan blade 200.

Example 5

As shown in FIGS. 12-14, a specific embodiment of a heat exchange fan assembly includes a centrifugal fan and a heat exchanger 201. The centrifugal fan includes a centrifugal fan blade 200, the diameter of the centrifugal fan blade 200 is L2; the heat exchanger 201 is provided on the air inlet side of the centrifugal fan, and the width of the heat exchanger 201 is L1, In order to make the heat exchanger 201 completely in the flow field driven by the centrifugal fan blade 200, so that the heat exchanger 201 can fully exchange heat with the air, it is necessary to satisfy L2≥L1; the width of the heat exchanger 201 and the centrifugal fan blade The ratio of the diameter of 200 is F. In order to ensure the heat exchange area of the heat exchanger 201, in this embodiment, 0.8 ≦ F ≦ 1. In this embodiment, to increase the contact area between the heat exchanger 201 and the air, the heat exchanger 201 uses a bent heat exchanger, and the surface of the heat exchanger 201 near the centrifugal fan blade 200 is concave The concave surface of the heat exchanger 201, the width L1 of the heat exchanger 201 refers to the distance between the two end points of the concave surface in the direction parallel to the end of the centrifugal fan blade 200, the lowest point of the concave surface and the centrifugal fan blade The distance between the inlet side of 200 is L3, and L3 <L2, the ratio of L2 and L3 is G, in order to allow air to pass through the heat exchanger 201 smoothly, and to ensure the best surface wind speed of the heat exchanger 201, Satisfying 1.5≤G≤1.77, the concave surface is an arc surface. As shown in FIG. 2, the inlet angle of the centrifugal fan blade 200 is α, and 135 ° ≦ α ≦ 145 °, where α is the diameter of the end face of the centrifugal fan blade 200 The angle of the straight line of the center of 200, this setting ensures the effective heat exchange area of the heat exchanger 201, because the height of the heat exchanger covered by the centrifugal fan blade is L4, and L4 = 2 * [L3 * tan ( α / 2)], so the product of L4 and the width L1 of the heat exchanger 201 is the effective heat exchange area of the heat exchanger 201.

Specifically, during operation, the air enters between the heat exchanger 201 and the centrifugal fan blade 200, is heat-extracted by the heat exchanger 201, is sucked in by the centrifugal fan, and is discharged from the upper end of the centrifugal fan. Since the ratio of the width of the heat exchanger 201 to the diameter of the centrifugal fan blade 200 satisfies 0.8 ≤ F ≤ 1, and the ratio of L2 to L3 satisfies 1.5 ≤ G ≤ 1.77, the cooperation between the centrifugal fan and the heat exchanger 201 is optimized The wind field makes the heat exchange between the air and the heat exchanger 201 uniform, giving full play to the capacity of the heat exchanger 201.

In an alternative embodiment, the heat exchanger 201 does not use a bending heat exchanger, and the width of the heat exchanger 201 means that the two ends of the heat exchanger 201 near the centrifugal fan blade 200 are in contact with the centrifugal wind The distance of the ends of the leaf 200 in parallel directions.

This embodiment also provides an air conditioner including the heat exchange fan assembly described above. Because the heat exchange performance of the heat exchanger 201 is better, the performance of the air conditioner is better.

Obviously, the above examples are only examples for clear explanation, and are not limitations on the implementation. For those of ordinary skill in the art, other different forms of changes or changes can be made based on the above description. There is no need to exhaustively list all implementations. The obvious changes or changes derived from this are still within the scope of protection created by this application.

Claims

A centrifugal fan is characterized by comprising a volute body (113), a centrifugal fan blade (200) disposed in the volute body (113), the volute body (113) includes a bottom plate (100), A front plate (308) and a side plate (101) provided between the bottom plate (100) and the front plate (308), and the air inlet of the centrifugal fan blade (200) is provided on the front plate (308) 308), the side plate (101) has a volute tongue (309), the volute tongue (309) is inclined from the side of the bottom plate (100) toward the side of the front plate (308) to The worm tongue gap is gradually reduced from the side of the bottom plate (100) toward the side of the front plate (308), and the volute gap C at the front plate (308) is smaller than that at the bottom plate (100) Volute gap D, and the difference between the volute gap D and the volute gap C is E.
The centrifugal fan according to claim 1, wherein E is 4% -6% of the diameter of the impeller of the centrifugal fan blade (200).
A centrifugal fan according to claim 2, wherein the arc surface of the volute tongue (309) adopts a conical arc, and the arc corresponding to each volute gap of the volute tongue (309) The radius of is gradually reduced from the side of the bottom plate (100) to the side of the front plate (308).
A centrifugal fan according to claim 3, wherein the radius of the volute (309) is 15-20mm.
A centrifugal fan according to claim 3, characterized in that the side diffuser section surface (310) of the centrifugal air duct of the centrifugal fan is directed from the side of the bottom plate (100) toward the front plate (308) ) Is inclined on one side, passing through the center of the centrifugal fan blade (200), and the tangent line that is tangent to the curved section of the volute (309) at the bottom plate (100) is the first tangent line, The tangent line passing through the center of the centrifugal fan blade (200) and tangent to the curved section of the volute tongue (309) on the front plate (308) is a second tangent line, the first tangent line The angle formed by the projection of the second tangent line on the plane perpendicular to the axial direction of the centrifugal fan blade (200) is the inclination angle β.
A centrifugal fan according to claim 5, wherein 7 ° ≤β≤12 °.
The centrifugal fan according to claim 6, characterized in that the volute opening of the air duct of the centrifugal fan is L5, the outlet distance of the expansion section of the centrifugal air duct is L6, and the ratio of L6 to L5 is M , And 2≤M≤3.
An air duct system, characterized in that it includes:

The air duct body includes the A-side air outlet (302) and the B-side air outlet (303);

A centrifugal fan is provided on the air duct body and is located between the A-side air outlet (302) and the B-side air outlet (303). The centrifugal fan includes at least one first centrifuge A fan (300), the first centrifugal fan (300) has two first air channels, which are the first A-side air channel (304) communicating with the A-side air outlet (302), and the B The first B-side air duct (305) communicating with the side air outlet (303), the centrifugal fan adopts a centrifugal fan according to any one of claims 1-7.
An air duct system according to claim 8, wherein two centrifugal fans are provided, including one first centrifugal fan (300), one second centrifugal fan (301), and the second The second centrifugal fan (301) has a second air duct (306), the second centrifugal fan (301) is disposed near the A side, the first centrifugal fan (300) is disposed near the B side, and the second air duct (306) communicates with the A-side air outlet (302).
An air duct system according to claim 9, wherein:

A guiding cavity (307) is provided on one side of the second centrifugal fan (301), the guiding cavity (307) connects the first A-side air duct (304) of the first centrifugal fan (300) ) Communicates with the A-side air outlet (302).
An air duct system according to claim 10, characterized in that

The volute body (113) of the first centrifugal fan (300) is aligned with the volute body (113) of the second centrifugal fan (301).
An air conditioner characterized by comprising an air duct system according to any one of claims 8-11.