CN118066143A - Fan device for air conditioner - Google Patents

Abstract

The invention provides a fan device which comprises a volute and an impeller arranged in the volute, wherein the volute comprises a volute front plate, a volute rear plate, a volute wall and a volute tongue, the volute wall surrounds the impeller in a ring shape, the volute front plate and the volute rear plate are respectively arranged on two sides of the volute wall, air inlets are respectively formed in the volute front plate and the volute rear plate, the volute wall, the volute front plate and the volute rear plate surround to form an air outlet, and the volute tongue is connected to the volute wall on one side of the air outlet, wherein the volute tongue is inwards concave towards the air outlet to form an inner concave part; at the peak of the concave portion, the maximum distance of concave inward of the concave portion accounts for 1-8% of the height of the air outlet. With the fan device according to the present invention, wind noise can be reduced without changing the ventilation amount of the fan device.

Description

Fan device for air conditioner

Technical Field

The invention relates to the technical field of air conditioning, in particular to a fan device for an air conditioning device.

Background

Air conditioning units are typically provided with fan means to generate an air flow that is conditioned by the air conditioning unit to achieve a predetermined air flow conditioning requirement. Common fan assemblies in air conditioning units include centrifugal fans having a volute, the volute of such fans typically comprising a volute wall with a smooth volute tongue structure thereon, such volute being easy to machine.

However, in the air conditioning apparatus, when the fan apparatus is operated, the air flow blown out as the fan impeller rotates reaches the smooth volute tongue at the same time, and when the flow velocity increases, a large pulse force is generated between the air flow and the volute tongue. As the fan impeller rotates, the pulse force superposition produces a significant air flow resonance noise.

At present, a multi-layer volute tongue structure with different shapes is proposed to solve the problem of noise caused by air flow resonance. For example, one conventional volute tongue structure includes two volute tongues and one volute tongue, wherein the outer side of one volute tongue is convex outward gradually protruding from the front and rear ends toward the middle and the outer side of the other volute tongue is concave inward gradually protruding from the front and rear ends toward the middle. However, the double-layer volute tongue is inconvenient to process and manufacture, and the manufacturing cost is correspondingly increased. In addition, since one of the tongues is of a concave structure, this will result in an increase in the gap between the tongue and the fan, which reduces the performance of the fan. The two volute tongue steps can lead to the reduction of the fluency of circulating air flow, possibly generate vortex and generate noise instead.

On the other hand, aiming at the double-carbon target, higher requirements are put forward on the energy-saving performance of the air conditioner, and meanwhile, the comfort requirements of users on the air conditioner are continuously improved. Users always want to be able to reach the desired temperature, humidity, air cleanliness, etc. more quickly, which requires a higher speed of operation of the fan unit in the air conditioning unit, but which at the same time causes more severe air flow resonances, which make the noise more noticeable. In addition, home offices are more common after epidemic situations occur, and extreme weather such as summer heat frequently occurs in the present year, and new requirements are also put on the silencing of the air conditioning apparatus during long-time high-load operation.

Accordingly, there is a need for a fan assembly that reduces fan noise without affecting the smoothness of the fan airflow and without significantly increasing manufacturing difficulties.

Disclosure of Invention

The invention provides a fan device for an air conditioning device, which comprises a volute and an impeller volute arranged in the volute, wherein the impeller volute comprises a volute front plate, a volute rear plate, a volute wall and a volute tongue, the volute wall surrounds an impeller and is annular, the volute front plate and the volute rear plate are respectively arranged at two sides of the volute wall, the volute front plate and the volute rear plate are respectively provided with an air inlet, the volute wall, the volute front plate and the volute rear plate are surrounded to form an air outlet, and the volute tongue is connected to the volute wall at one side of the air outlet; wherein the volute tongue is concave towards the air outlet to form an inner concave part, and the maximum inward concave distance of the inner concave part is 1-8% of the height of the air outlet at the vertex of the inner concave part.

The volute tongue is concave towards the air outlet to form an inner concave part, so that the height of the air outlet in the width direction from the front plate of the volute to the rear plate of the volute is changed, and meanwhile, the maximum distance of the inner concave part is controlled within the range of 1-8% of the height of the air outlet, so that noise is reduced under the condition that the air quantity is not attenuated basically.

According to one aspect of the invention, the fan device is a multi-wing centrifugal fan device, the impeller of the multi-wing centrifugal fan having a center plate arranged perpendicular to the direction of the rotation axis of the impeller, the center plate being in the same plane perpendicular to the rotation axis as the apex of the concave portion, wherein the concave portion is arranged symmetrically with respect to the apex and the plane in which the center plate lies.

For the multi-wing centrifugal fan, the air inlets are symmetrically arranged at the left side and the right side, and when the top points of the concave parts are corresponding to the middle disc, the noises generated by the blades at the two sides of the middle disc can be mutually counteracted, so that the noises generated by the fan device are further eliminated.

According to a further aspect of the invention, the radius at the connection of the volute tongue with the volute front plate and the volute rear plate is R1, the radius at the apex of the inner recess is R2, the maximum inward concave distance of the apex of the inner recess Δr=r2-R1, wherein,

Wherein U is the airflow velocity at the vertex of the volute tongue, deltaT is the time interval between the airflow blown by two adjacent blades and flapping on the volute tongue, omega is the rotating speed of the impeller, N is the number of the blades of the impeller, epsilon is a constant, epsilon is 2 when the blades on two sides of a middle disc of the impeller are arranged in a staggered manner, and epsilon is 1 when the blades on two sides of the middle disc are arranged in an aligned manner.

Thus, ΔR is set to ensure that the time interval between impingement of the same blade-slapping airflow onto the volute tongue is within ΔT, which will help reduce the total sound value produced by the same blade-slapping airflow onto the volute tongue.

According to a further aspect of the invention, the volute wall, the volute front plate and the volute rear plate are surrounded to form a rectangular air outlet, the rectangular area is S, the concave part is inwards concave to enable the area of the air outlet to be reduced by S1, and the ratio of the area S1 to the area S is in the range of 1-4%.

According to a further aspect of the invention, the radius at the junction of the volute tongue with the volute front plate and the volute rear plate is R1, and the radius at the apex of the concave portion of the volute is R2, wherein R1: R2 is 1:1.1-1.5, and the radius of the impeller is R, R2: r is 1: 1.3-1:1.7.

According to still another aspect of the present invention, the inner surface of the concave portion of the volute tongue and the horizontal plane of the opposite volute tongue where the two ends of the volute tongue are connected with the volute front plate and the volute rear plate are seen in the direction perpendicular to the air outlet form an included angle alpha,

Wherein, the maximum inward concave distance of the peak of the concave part is DeltaR, and A is the distance from the peak to the volute front plate or the volute rear plate.

According to a further aspect of the invention, a first edge of the volute tongue is connected to the volute wall and a second edge of the volute tongue is located in the air outlet, wherein the second edge is provided with a tooth-like structure, which is any one of sharp teeth and round teeth.

The edge of the volute tongue is provided with the tooth-shaped structure, so that the airflow can be divided when the airflow passes through the air outlet, and the auxiliary noise reduction effect is achieved.

According to a further aspect of the invention, the toothed structure has a plurality of teeth, each of said teeth having an end shaped at substantially 90 ° and said ends being provided with rounded corners, the distance between the ends of two adjacent teeth being in the range 0.5mm-1 mm.

According to yet another aspect of the invention, the tooth structure has a plurality of teeth, each tooth having a tooth height L1 and a tooth width L2, L1: l2 is 1:2.

By adopting the fan device, the set height of the air outlet is reduced by deforming the volute tongue towards the air outlet, so that the time points of the air flow beaten by the same blade in the impeller to impact on the volute tongue are staggered, and the noise can be reduced on the premise of ensuring the air quantity and the air flow smoothness.

The volute tongue is provided with arch-shaped parts with different radiuses at different positions, the radius R1 of the end part of the volute tongue connected with the volute front plate and the volute rear plate is smaller, the radius R2 at the vertex of the concave part at the middle position of the volute tongue is larger, the height occupied by the concave part is controlled by the radius difference of the volute tongue and the volute rear plate, and the size of the volute tongue is easy to accurately control.

The present invention also provides an air conditioning apparatus having the above-described fan apparatus, the air conditioning apparatus further having an air flow caused by the fan apparatus flowing into the heat exchanger, disposed downstream of the fan apparatus. The outlet vortex tongue of the fan device reduces noise, and the vortex tongue extension part at the downstream of the vortex tongue is further smoothly guided, so that the air flow finally passing through the heat exchanger is quite uniform, thereby ensuring the heat exchanger to have high-efficiency heat exchange performance.

Drawings

For a more complete understanding of the present invention, reference is made to the following description of exemplary embodiments taken in conjunction with the accompanying drawings, in which:

fig. 1 illustrates a perspective view of a scroll case of a fan apparatus for an air conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 2 shows an end view of an air outlet of a volute of a fan device for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 3 shows a side view of a volute of a fan apparatus for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 4 shows an end view of an air outlet of a fan apparatus for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 5 shows a partial perspective view of a volute of a fan apparatus for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 6 shows an enlarged partial schematic view of a volute tongue of a fan apparatus for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 7 is a partially enlarged schematic view showing a tooth-like structure of a volute tongue of a fan device for an air-conditioning apparatus according to a preferred embodiment of the present invention.

Fig. 8 is a perspective view showing an air conditioning apparatus adapted to mount a fan apparatus according to a preferred embodiment of the present invention.

Fig. 9 is a perspective view showing an internal structure of an air conditioning apparatus mounted with a fan apparatus according to a preferred embodiment of the present invention.

List of reference numerals

1 Air conditioning device

100 Fan device

10 Spiral case

11 Volute wall

12 Spiral case front plate

13 Spiral case back plate

16 Volute tongue

161 Inner concave part

162 Vertex

17 Tooth structure

171 Tooth portion

20 Impeller

21 Middle plate

22-Blade

50 Air outlet

60 Air inlets

L axis of rotation

L1 tooth height

L2 tooth width

200. Heat exchanger

Detailed Description

The present invention will be further described with reference to specific embodiments and drawings, in which more details are set forth in the following description in order to provide a thorough understanding of the present invention, but it will be apparent that the present invention can be embodied in many other forms than described herein, and that those skilled in the art may make similar generalizations and deductions depending on the actual application without departing from the spirit of the present invention, and therefore should not be construed to limit the scope of the present invention in terms of the content of this specific embodiment.

Fig. 4 shows a fan apparatus 100 according to a preferred embodiment of the present invention. The fan apparatus 100 is used for an air conditioning apparatus, and the fan apparatus 100 is installed in a housing of the air conditioning apparatus for causing an air flow to flow from an air flow inlet of the air conditioning apparatus to an air flow outlet of the air conditioning apparatus in a predetermined direction. As shown in fig. 4, the fan apparatus 100 mainly includes a scroll casing 10 and an impeller 20 disposed in the scroll casing 10, and the impeller 20 rotates about a rotation axis L in the scroll casing 10 by a driving device (not shown).

Fig. 1, 2 and 3 show perspective, end and side views, respectively, of a volute 10 of a fan apparatus 100 according to a preferred embodiment of the invention. The volute 10 mainly comprises a volute front plate 12, a volute rear plate 13, a volute wall 11 and a volute tongue 16. As shown in fig. 1, the volute wall 11 is generally annular and is configured to enclose the impeller 20 therein, and the generally annular volute wall 11 may be spliced from a plurality of wall components. The volute front plate 12 and the volute rear plate 13 have substantially corresponding shapes, which are provided on both sides of the volute wall 11, respectively. Preferably, the impeller 20 inside the volute 10 is a double-sided air inlet impeller 20, and correspondingly, two air inlets 60 are respectively formed in the middle parts of the volute front plate 12 and the volute rear plate 13, and air flows enter the space inside the volute 10 along the rotation axis L (see fig. 4) of the impeller 20.

As shown in fig. 1 and 2, the volute 10 has an air outlet 50, which air outlet 50 is surrounded by the volute wall 11, the volute front plate 12 and the volute rear plate 13, and the air outlet 50 directs the flow of air to flow out of the volute 10 in a direction perpendicular to the rotation axis L.

Preferably, as shown in fig. 2, the volute wall 11 has two generally parallel and straight outlet edge portions, the volute front plate 12 and the volute rear plate 13 have mutually parallel and straight outlet edge portions, and the outlet edge portions of the volute wall 11 are substantially perpendicular with respect to the outlet edge portions of the volute front plate 12 and the volute rear plate 13. Thus, the scroll wall 11, the scroll front plate 12 and the scroll rear plate 13 are combined together to form one rectangular air outlet 50, the relative distance between the inner surfaces of the two outlet edge portions of the scroll wall 11 is defined as the set height of the air outlet 50, and the distance between the scroll front plate 12 and the scroll rear plate 13 is defined as the set width of the air outlet 50.

Further, at the air outlet 50, the volute tongue 16 is connected to an outlet edge portion of one side of the volute wall 11, as shown in fig. 2, the volute tongue 16 being located below the air outlet 50. With respect to the direction of the air outlet 50, the volute tongue 16 is recessed toward the inside of the air outlet 50 on the periphery of the air outlet 50 to form an inner recess 161, and the inner recess 161 is arranged such that the lower surface of the air outlet 50 formed by the volute tongue 16 is not parallel to the rotation axis L of the impeller 20, but is inclined in two stages with respect to the rotation axis L, so that the actual height of the air outlet 50 is inconsistent in the width direction of the air outlet 50, the actual height of the air outlet 50 is smaller in the middle position in the width direction, and is larger in the two end positions, that is, the gap between the outer periphery of the impeller 20 and the volute tongue 16 is nonuniform, and the gap gradually increases from the middle to the two end sides. In the preferred embodiment, the recess 161 has an apex 162 where the recess 161 is recessed inwardly by a maximum distance, i.e., where the actual height of the outlet 50 at the apex 162 is a minimum.

The volute tongue in the conventional fan device is conventionally designed to have a circular arc shape, and has a uniform radius in the horizontal direction of the air outlet. As shown in fig. 5, the volute tongue 16 itself is also a substantially circular arc-shaped member, the convex surface of the circular arc being directed toward one side of the air outlet 50, but unlike the conventional volute tongue, the circular arc shape of the volute tongue 16 has a larger radius R2 at both ends near the front plate 12 and the rear plate 13, and has a smaller radius R1 at both ends near the front plate 12 and the rear plate 13, and the radius of the volute tongue 16 of the circular arc becomes uniformly and gradually smaller in the horizontal direction toward both ends of the front plate 12 and the rear plate 13, that is, the radius becomes gradually smaller linearly from R2 to R1.

It is particularly advantageous if the recess 161 of the volute tongue 16 is recessed towards the interior of the air outlet by a distance of 1-8% of the set height of the air outlet 50, in other words, the actual height of the air outlet 50 at the apex 162 of the recess 161 is reduced by 1-8% relative to its set height. More specifically, the recessed distance is designed to be 5-8% of the set height of the air outlet 50.

The structure of the volute tongue 16 has a significant influence on the noise of the fan apparatus 100, and by configuring the volute tongue 16 to have the concave portion 161 so that the lower periphery of the air outlet 50 is obliquely arranged with respect to the rotation axis L of the impeller 20, the noise reduction effect can be achieved by reasonable superposition of the audio when the volute tongue 16 changes the flow direction of the air flow at the air outlet 50, and the concave distance occupies 1-8% of the set height of the air outlet 50, so that the air flow is not substantially attenuated while the noise is reduced.

In other alternative embodiments, the concave portion 161 may be configured to have an arc shape in the width direction, that is, the concave portion 161 is arc-shaped in a direction parallel to the rotation axis L, and the highest point of the arc shape is the apex of the concave portion. Whether a curved or straight angled recess, the shape of the side surface of the recess 161 of the volute tongue 16 facing the air outlet 50 is continuously and smoothly varying, which minimizes the flow resistance to the air flow.

On the other hand, the relationship between noise and airflow attenuation can be balanced by setting the ratio of the area occupied by the concave portion 161 to the set area (i.e., the product of the set height and the set width) of the air outlet 50. Specifically, for the air outlet 50 formed by surrounding the volute walls 11, the volute front plate 12, and the volute rear plate 13, the rectangular area thereof is S, and the concave portion 161 of the volute tongue 16 reduces the area of the rectangular air outlet 50 by S1, it is preferable that the ratio of the area S1 to the area S is in the range of 1-4%.

In the preferred embodiment, the fan apparatus 100 is a multi-wing centrifugal fan apparatus 100, and as described above, the impeller 20 of the multi-wing centrifugal fan apparatus 100 is a double-sided inlet impeller. Specifically, the impeller 20 has a center plate 21 arranged perpendicularly to the rotation axis direction of the impeller 20, and both the left and right sides of the center plate 21 have blades 22, the blades 22 extending in a direction parallel to the rotation axis, and the lengths of the blades 22 on both sides being the same. The blades 22 on both sides may be aligned or may be offset as shown in fig. 4. The center plate 21 is located approximately at the widthwise middle position from the widthwise direction of the air outlet 50. As shown in fig. 4, the recess 161 in the tongue 16 is particularly arranged with its apex 162 aligned with the central disk 21 of the impeller 20, which lie in the same plane perpendicular to the axis of rotation, this arrangement being capable of symmetrically varying the air flow on both sides of the central disk 21, so as to achieve an optimal noise reduction.

As shown in fig. 5, the volute tongue 16 is a component attached to the volute wall 11 that has an arcuate configuration with its arcuate face facing the outer surface of the impeller 20. To form the concave portion 161, the arcuate surfaces have different radii at the intermediate and both ends thereof. Specifically, the radius at the junction of the volute tongue 16 with the volute front plate 12 and the volute rear plate 13 is R1, and the radius at the apex 162 of the concave portion 161 is R2, so that the maximum distance Δr at which the apex 162 of the concave portion 161 is recessed inward is the difference between R2 and R1, as shown in fig. 4. The preferred maximum distance Δr for the inward recession of the apex 162 of the fillet 161 can be calculated using equation 1 below:

Where U is the airflow velocity at the apex of the volute tongue 16, ω is the impeller rotational speed, N is the number of blades 22 of the impeller, Δt is the time interval between the adjacent two blades blowing out the airflow to flap on the volute tongue, ε is a constant, when the blades 22 on both sides of the middle plate 21 of the impeller 20 are arranged in a staggered manner, that is, the blades 22 on both sides of the middle plate 21 are not on a straight line, ε=2, and when the blades on both sides of the middle plate 21 are arranged in an aligned manner, that is, the blades 22 on both sides of the middle plate 21 are correspondingly arranged on a straight line, ε=1.

That is, preferably, ΔR should be set such that the time interval between the impingement of the air stream from the same blade onto the volute tongue is within ΔT, which will help reduce the total sound value produced by the impingement of the air stream from the same blade onto the volute tongue. On the other hand, preferably, the radius between the volute tongue 16 and the connection between the volute front plate 12 and the volute rear plate 13 is R1, and the radius at the vertex 162 of the concave portion 161 of the volute tongue 16 is R2, wherein R1 and R2 are preferably equal to 1: 1.1-1.5. On the other hand, the impeller 20 generally has a generally cylindrical shape about an axis of rotation, and a measured impeller radius from the axis of rotation L is R, then R2: r is preferably set at 1: 1.3-1:1.7.

Fig. 6 shows an enlarged partial schematic view of the volute tongue 16 of the fan apparatus 100 for an air-conditioning apparatus according to the preferred embodiment of the present invention. As shown in fig. 6, the inner surface of the concave portion 161 of the volute tongue 16 preferably has an angle α of less than 5 ° with respect to a horizontal plane (i.e., a horizontal plane parallel to the rotation axis L of the impeller 22) at which both ends of the volute tongue 16 are connected to the volute front plate 12 and the volute rear plate 13, viewed in a direction perpendicular to the air outlet 50, that is:

Wherein, the maximum inward concave distance of the vertex 162 of the concave portion 161 of the volute tongue 16 is Δr, and a is the distance between the vertex 162 and the volute front plate 12 or the volute rear plate 13.

In a preferred embodiment, the included angle α may be selected to be in the range of 1.5 ° to 3 °, and the two included angles near the volute front plate 12 and the rear plate 13 are symmetrically arranged.

On the other hand, the volute tongue 16 is provided with a tooth-like structure 17 at the middle edge of the air outlet 50, so that when the air flows out from the air outlet 50 of the volute 10, the tooth-like structure 17 can cut the air flow to further reduce noise.

As shown in fig. 7, the tooth-like structure 17 of the edge of the volute tongue 16 preferably has a plurality of teeth 171, and the teeth 171 may be rounded teeth or pointed teeth. In a preferred embodiment, the end of each tooth 171 forms a substantially 90 ° corner, and is preferably provided with a rounded chamfer. The distance d between the ends of two adjacent teeth 171 is preferably in the range of 0.5mm-1 mm.

Further, as shown in fig. 7, the tooth-like structure of the edge of the volute tongue 16 preferably has a plurality of teeth 171, each having a tooth height L1 and a tooth width L2, L1: l2 is 1:2. The plurality of teeth 171 may be equally spaced on the edge of the volute tongue 16. Preferably, the tooth height L1 is set to 1mm and the tooth width is set to 2mm.

Preferably, the plurality of teeth 171 and the concave portion 161 are symmetrically arranged with respect to a plane of the middle disk 21 of the impeller 20, which allows the teeth 171 to uniformly cut the air flow on both sides of the middle disk 21.

By adopting the fan device, the set height of the air outlet is reduced by deforming the volute tongue towards the air outlet, and the noise can be reduced on the premise of ensuring the air quantity and the air flow smoothness.

The volute tongue is provided with arch-shaped parts with different radiuses at different positions, the radius R1 of the end part of the volute tongue connected with the volute front plate and the volute rear plate is smaller, the radius R2 at the vertex of the concave part at the middle position of the volute tongue is larger, the height occupied by the concave part is controlled by the radius difference of the two parts, and the size of the concave part of the volute tongue is easy to accurately control.

Fig. 8 and 9 show an outer perspective view and an inner perspective view, respectively, of an air conditioning device 1 having a fan device according to the present invention.

The air conditioning apparatus 1 includes an indoor unit casing, a heat exchanger 200 mounted inside the casing, and a fan apparatus 100, and further includes a fan motor that drives the fan apparatus 100. The fan assembly provides an airflow to a downstream heat exchanger. The fan apparatus has the scroll casing 10 of the above-described structure. It should be appreciated that when the fan apparatus 100 is installed inside the housing, the volute tongue may be located above or below the air outlet with respect to the installed position of the air-conditioning apparatus 1, depending on the arrangement of the air-handling apparatus 100 within the housing.

The fan device according to the invention is particularly advantageous in combination with an air-conditioning device. The air conditioning device is significantly reduced in noise, especially when the fan motor is operated at high speed, thereby improving user comfort. Meanwhile, for the downstream heat exchanger for receiving the air flow, no loss exists in the aspects of the air quantity and fluency of the air flow entering the downstream heat exchanger, and the working efficiency of the heat exchanger is ensured.

For the fan device provided in the air-conditioning apparatus shown in fig. 8 and 9, there are preferably 38 to 48 blades, and a center tray supporting the blades is included, and air inlets are symmetrically arranged on both left and right sides of the center tray. Meanwhile, the rotation speed of the impeller may be set in the range of 1000-1500rpm per minute, and at this time, ΔR may be in the range of 3mm to 6 mm.

More specifically, in one specific example, a fan device for an air conditioning device has 41 blades, and includes a center plate supporting the blades, air inlets are symmetrically arranged on both left and right sides of the center plate, and Δr is set to 3mm and α is selected to 1.7 ° correspondingly when the rotational speed is set to 1300 rpm. In another specific example, a fan device for an air conditioning device has 45 blades and includes a center tray supporting the blades, air inlets are symmetrically arranged at both left and right sides of the center tray, and Δr is set to 4mm and α is selected to be 2.3 ° when the rotational speed is set to 1100 rpm. In contrast to equation 1 above, the value of Δr in these examples is more preferably selected to be in the range of 1/3 to 2/3 of u×Δt, and the dimensions are set such that the attenuation of the outlet air volume is significantly reduced.

While the invention has been described in terms of preferred embodiments, it is not intended to be limiting, but rather to the invention, as will occur to those skilled in the art, without departing from the spirit and scope of the invention. Therefore, any modification, equivalent variation and modification of the above embodiments according to the technical substance of the present invention fall within the protection scope defined by the claims of the present invention.

Claims (10)

1. A fan device for an air conditioning device, the fan device comprising a volute and an impeller arranged in the volute, the volute comprising a volute front plate, a volute rear plate, a volute wall and a volute tongue, the volute wall being annular around the impeller, the volute front plate and the volute rear plate being respectively arranged on two sides of the volute wall, the volute front plate and the volute rear plate being respectively provided with an air inlet,

The volute casing wall, the volute casing front plate and the volute casing rear plate are surrounded to form an air outlet, and the volute tongue is connected to the volute casing wall at one side of the air outlet;

The method is characterized in that:

the volute tongue is concave towards the air outlet to form an inner concave part;

at the peak of the concave part, the maximum distance of the concave part to be concave inwards accounts for 1-8% of the height of the air outlet.

2. A fan apparatus for an air conditioning apparatus as recited in claim 1, wherein the fan apparatus is a multi-wing centrifugal fan apparatus having an impeller of the multi-wing centrifugal fan having a center plate arranged in a direction perpendicular to a rotation axis of the impeller, the center plate being in a same plane as an apex of the concave portion perpendicular to the rotation axis,

Wherein the concave portions are symmetrically arranged about the apex and a plane in which the center plate lies.

3. A fan apparatus for an air conditioner as defined in claim 2, wherein,

The radius of the connection part of the volute tongue and the volute front plate and the volute rear plate is R1, the radius of the vertex of the inner concave part is R2, the maximum distance delta R=R2-R1 of the inward concave of the vertex of the inner concave part,

Wherein,

Wherein U is the airflow velocity at the vertex of the volute tongue, ω is the rotational speed of the impeller, N is the number of blades of the impeller, ε is a constant, ΔT is the time interval between the air streams blown by two adjacent blades and flapped on the volute tongue, ε is 2 when the blades on two sides of the middle disc of the impeller are arranged in a dislocation manner, and ε is 1 when the blades on two sides of the middle disc are arranged in an aligned manner.

4. A fan apparatus for an air conditioner as defined in claim 1, wherein,

The volute wall, the volute front plate and the volute rear plate are surrounded to form a rectangular air outlet, the rectangular area is S, the concave part is inwards concave to enable the area of the air outlet to be reduced by S1, and the ratio of the area S1 to the area S is in the range of 1-4%.

5.A fan apparatus for an air conditioner as defined in claim 1, wherein,

The radius of the connection part of the volute tongue and the volute front plate and the volute rear plate is R1, the radius of the vertex of the concave part of the volute tongue is R2, wherein R1:R2 is as follows: in the range of 1.1-1.5,

And the radius of the impeller is R, R2: r is 1: 1.3-1:1.7.

6. A fan apparatus for an air conditioner as defined in claim 1, wherein,

The peak of the fillet is recessed inward by a maximum distance deltar,

The included angle between the inner surface of the concave part of the volute tongue and the horizontal plane of the connection part of the volute tongue, the volute front plate and the volute rear plate is alpha, which is opposite to the volute tongue, when the direction perpendicular to the air outlet is observed,

Wherein A is the distance from the vertex to the front plate of the volute or to the rear plate of the volute.

7. A fan apparatus for an air conditioner as defined in claim 1, wherein,

The first edge of the volute tongue is connected with the volute wall, the second edge of the volute tongue is positioned in the air outlet,

Wherein the second edge is provided with a toothed structure, and the toothed structure is any one of sharp teeth and round teeth.

8. The fan apparatus as claimed in claim 7, wherein the tooth structure has a plurality of teeth, each of the teeth has an end formed at substantially 90 ° and is provided with a circular arc chamfer, and a distance between the ends of adjacent two of the teeth is in a range of 0.5mm to 1 mm.

9. The fan apparatus as claimed in claim 7, wherein the tooth structure has a plurality of teeth, each of the teeth having a tooth height L1 and a tooth width L2, L1: l2 is 1:2.

10. An air conditioning device, the air conditioning device comprising:

the fan apparatus as claimed in any one of claims 1 to 9; and

A heat exchanger disposed downstream of the fan device to cause an airflow caused by the fan device to flow into the heat exchanger.