CN218934850U

CN218934850U - Centrifugal fan

Info

Publication number: CN218934850U
Application number: CN202222970111.8U
Authority: CN
Inventors: 蒋鹭; 穆景阳; 李维强; 余兆开
Original assignee: Aitaisi Thermal System Research And Development Shanghai Co ltd
Current assignee: Aitaisi Thermal System Research And Development Shanghai Co ltd
Priority date: 2022-11-08
Filing date: 2022-11-08
Publication date: 2023-04-28
Anticipated expiration: 2032-11-08

Abstract

The utility model relates to the technical field of centrifugal fans, and discloses a centrifugal fan which comprises an impeller, a lower static ring and a volute, wherein the impeller and the lower static ring are of annular structures and are positioned in the volute, the impeller rotates around the axial direction of the impeller relative to the volute to suck air flow, so that the axial first end of the impeller is an air inlet of the impeller, and the radial outer peripheral surface of the impeller is provided with an air outlet of the impeller. In addition, the lower static pressure ring is arranged at the second end of the impeller in the axial direction and extends towards the first end of the impeller in the axial direction of the impeller, so that the air flow flowing out from the air outlet at the bottom of the impeller is blocked by the lower static pressure ring to form backflow between the bottom of the impeller and the bottom of the volute, the stability of a flow field around the impeller is protected, and the problems of noise and abnormal sound caused by backflow of the centrifugal fan are solved.

Description

Centrifugal fan

Technical Field

The utility model relates to the technical field of centrifugal fans, in particular to a centrifugal fan.

Background

The internal airflow of the blower is very complex, whether the internal flow field is smooth, whether the internal flow field has a turbulent backflow phenomenon or not, and the like, so that the performance of the blower can be influenced, the overall noise of the blower can be influenced, and even the problems of the blower such as rolling and abnormal sound are caused. The prior patent (CN 114352573A) discloses a compact centrifugal fan, which is characterized in that an anti-vortex ring is arranged at an air inlet of an impeller, so that partial airflow is limited to flow to the side surface of the impeller along the axial direction of the impeller in the rotation process of the impeller, and the partial airflow enters the impeller again from a position close to the air inlet to form axial secondary flow, thereby bypassing the problem of the flow field in the volute so as to prevent the centrifugal fan from surging, shaking and the like. However, besides the air inlet of the centrifugal fan, a backflow is easily formed between the bottom of the impeller, namely, the bottom of the volute and the bottom of the impeller after the air flows out of the impeller, and when the backflow is strong, the surrounding flow field is disturbed, so that the sound of the fan is generated.

Therefore, a centrifugal fan is needed to solve the above problems.

Disclosure of Invention

The utility model aims to provide a centrifugal fan which can solve the problem of backflow at an air outlet of an impeller so as to effectively improve the problems of noise and abnormal sound of the centrifugal fan.

The technical scheme adopted by the utility model is as follows:

a centrifugal fan, comprising:

the impeller is in an annular structure, the first axial end of the impeller is an air inlet of the impeller, and the radial outer circumferential surface of the impeller is provided with an air outlet of the impeller;

the lower static ring is arranged at the second axial end of the impeller in a surrounding manner and extends towards the first axial end along the axial direction of the impeller;

the impeller and the lower static ring are both positioned in the volute, and the impeller rotates around the axial direction of the impeller relative to the volute.

Optionally, the lower static ring is uniform in height along the axial direction of the impeller.

Optionally, the height of the lower static ring is not completely uniform along the axial direction of the impeller.

Optionally, the centrifugal fan further comprises a flange, the volute and the lower static ring are both fixed relative to the flange, and the impeller rotates relative to the flange.

Optionally, the lower static ring and the volute are arranged as an integral structural member, and the integral structural member is fixed on the flange plate; or alternatively, the first and second heat exchangers may be,

the lower static ring and the flange plate are arranged into an integrated structural member, and the volute is fixed on the flange plate.

Optionally, the lower static pressure ring comprises an extension part and a connecting part which are connected, the extension part extends along the axial direction of the impeller, and the extension part is connected with the volute or the flange plate through the connecting part.

Optionally, the centrifugal fan further comprises a motor, the motor and the impeller are respectively located at two sides of the flange plate in the axial direction, and an output shaft of the motor penetrates through the flange plate to be connected with the impeller.

Optionally, along the axial direction of the impeller, the distance between the second end and the flange plate is L1, and L1 is more than or equal to 2mm and less than or equal to 10mm.

Optionally, along the radial direction of the impeller, the distance between the impeller and the lower static pressure ring is L2, and L2 is more than or equal to 2mm and less than or equal to 12mm.

Optionally, along the axial direction of the impeller, the height of the impeller is H1, and the height of the lower static ring is H2,0.1H1 is less than or equal to H2 and less than or equal to 0.5H1.

The beneficial effects of the utility model are as follows:

the centrifugal fan comprises an impeller, a lower static ring and a volute, wherein the impeller and the lower static ring are of annular structures and are positioned in the volute, the impeller rotates around the axial direction of the impeller relative to the volute to suck air flow, so that the axial first end of the impeller is an air inlet of the impeller, and the radial outer peripheral surface of the impeller is provided with an air outlet of the impeller. In addition, the lower static pressure ring is arranged at the second end of the impeller in the axial direction and extends towards the first end of the impeller in the axial direction of the impeller, so that the air flow flowing out from the air outlet at the bottom of the impeller is blocked by the lower static pressure ring to form backflow between the bottom of the impeller and the bottom of the volute, the stability of a flow field around the impeller is protected, and the problems of noise and abnormal sound caused by backflow of the centrifugal fan are solved.

Drawings

Fig. 1 is a schematic diagram of a centrifugal fan with a first view angle provided in an embodiment of the present utility model assembled in an air conditioning system;

FIG. 2 is a schematic diagram of a centrifugal fan with a second view angle according to an embodiment of the present utility model assembled in an air conditioning system;

FIG. 3 is a schematic view of a part of the structure of a centrifugal fan according to an embodiment of the present utility model;

fig. 4 is a partial cross-sectional view of a centrifugal fan provided by an embodiment of the utility model.

In the figure:

1. an impeller; 10. a blade; 11. a first end; 12. a second end;

2. a lower static ring; 21. an extension; 22. a connection part;

3. a volute; 31. a volute tongue;

4. a flange plate;

5. and a motor.

Detailed Description

In order to make the technical problems solved, the technical scheme adopted and the technical effects achieved by the utility model more clear, the technical scheme of the utility model is further described below by a specific embodiment in combination with the attached drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the utility model and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the drawings related to the present utility model are shown.

In the description of the present utility model, unless explicitly stated and limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

In the present utility model, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "left", "right", and the like are orientation or positional relationships based on those shown in the drawings, merely for convenience of description and simplicity of operation, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the utility model. Furthermore, the terms "first," "second," and the like, are used merely for distinguishing between descriptions and not for distinguishing between them.

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings.

As shown in fig. 1 to 4, the present embodiment provides a centrifugal fan, which can avoid a backflow phenomenon between the bottom of an impeller 1 and the bottom of a volute 3, thereby ensuring the stability of the flow around the impeller 1 and improving the problems of noise, abnormal sound and the like caused by backflow of the centrifugal fan.

Specifically, centrifugal fan includes impeller 1, lower static pressure ring 2 and spiral case 3, spiral case 3 has annular accommodation chamber, impeller 1 rotates to set up in this accommodation intracavity, impeller 1 is annular structure, it can rotate around self axial, through the rotation of impeller 1, the gas will get into from the axial first end 11 of impeller 1, namely the air intake of impeller 1, then again through the radial outer peripheral face of impeller 1, namely the air outlet of impeller 1, impeller 1 includes a plurality of blades 10, a plurality of blades 10 set up along annular structure's circumference interval, the clearance between two adjacent blades 10 is the air outlet of impeller 1 promptly. However, when the air flow is sucked into the impeller 1 from the air inlet of the impeller 1, and flows into the volute 3 after the impeller 1 rotates, the air flow flowing out of the impeller 1 is liable to form a backflow between the bottom of the impeller 1, that is, the circumferential second end 12 of the impeller 1 and the bottom of the volute 3, and the backflow is strong, not only the surrounding flow field is disturbed, but also the sound of the centrifugal fan is caused. Therefore, in the present embodiment, the lower static pressure ring 2 is disposed around the second end 12 of the impeller 1 in the axial direction, and extends toward the first end 11 of the impeller 1 along the axial direction of the impeller 1, and the lower static pressure ring 2 is located outside the impeller 1 and also located in the volute 3, so that the airflow flowing out from the bottom of the impeller 1 will not flow back to the bottom of the impeller 1 due to the blocking of the lower static pressure ring 2, thereby protecting the stability of the flow field around the impeller 1, and improving the abnormal sound such as the booming caused by the backflow.

Alternatively, the lower static ring 2 is uniform in height along the axial direction of the impeller 1. I.e. provides a consistent blocking effect for the backflow of the air flow at each position of the centrifugal fan.

Alternatively, the height of the lower static ring 2 is not exactly uniform along the axial direction of the impeller 1. The heights of the lower static rings 2 at different backflow positions can be set according to the strength of backflow at the bottom of the impeller 1 of the centrifugal fan under the actual working condition. As shown in fig. 1, in actual use, the backflow in the vicinity of the volute tongue 31 corresponding to the volute 3 is generally the strongest, and thus the lower static ring 2 at the volute tongue 31 is disposed the highest.

Along the axial direction of the impeller 1, the higher the lower static ring 2 is, the larger the influence of the lower static ring 2 on the air outlet flow of the centrifugal fan is, so that a proper height value of the lower static ring 2 is required to be selected according to the actual backflow condition so as to reach the optimal balance point for improving the air outlet flow of the centrifugal fan and reducing the noise of the centrifugal fan. Preferably, the height of the impeller 1 is H1, and the height of the lower static ring 2 is H2, and 0.1H1 is less than or equal to H2 and less than or equal to 0.5H1.

Further, the centrifugal fan further comprises a flange 4, the volute 3 and the lower static ring 2 are fixed relative to the flange 4, and the impeller 1 rotates relative to the flange 4. The volute 3, the lower static ring 2 and the flange 4 are directly connected, and the impeller 1 is directly driven by the driving component and keeps relative rotation with the flange 4 through the bearing component. In addition, because the impeller 1 may deviate along the axial direction thereof during rotation, a certain distance should be kept between the impeller 1 and the lower static pressure ring 2 along the radial direction of the impeller 1, and a certain distance should be kept between the impeller 1 and the flange 4 along the axial direction of the impeller 1, so that the impeller 1 is destroyed because of interference friction or jamming with the lower static pressure ring 2 and the flange 4 caused by the deviation during rotation of the impeller 1.

Preferably, the distance between the second end 12 of the impeller 1 and the flange 4 along the axial direction of the impeller 1 is L1, and L1 is more than or equal to 2mm and less than or equal to 10mm.

Preferably, along the radial direction of the impeller 1, the distance between the impeller 1 and the lower static pressure ring 2 is L2, L2 is less than or equal to 2mm and less than or equal to 12mm, the excessive distance between the impeller 1 and the lower static pressure ring 2 is avoided, and the backflow blocking effect is weakened.

The relative fixation of the lower static pressure ring 2 and the volute 3 and the flange 4 has at least two structures, as shown in fig. 4, in this embodiment, the lower static pressure ring 2 and the volute 3 are arranged as an integral structural member, a side surface of the flange 4, which is close to the impeller 1, is provided with a mounting groove, the integral structural member is provided with a mounting protrusion adapted to the mounting groove, and the mounting protrusion is inserted into the mounting groove, so that the relative fixation of the integral structural member and the flange 4 is realized, and the mounting procedure of the centrifugal fan can be simplified.

In other embodiments, the lower static ring 2 and the flange 4 may be provided as an integral structure, and the volute 3 is fixed to the flange 4. The specific relative positions of the scroll 3 and the lower static ring 2 and the flange 4 may depend on the aforementioned range of the intervals between the impeller 1, the flange 4 and the lower static ring 2.

Optionally, the lower static pressure ring 2 includes an extension 21 and a connection 22 connected, wherein the extension 21 is parallel to the axial direction of the impeller 1 for blocking the swirling air flow, and the connection 22 is directly connected with the flange 4 or the volute 3, i.e. the extension 21 is connected with the flange 4 or the volute 3 through the connection 22, so as to fix the lower static pressure ring 2 by the two structures.

In this embodiment, the driving component is a motor 5, as shown in fig. 4, the motor 5 and the impeller 1 are respectively located at two sides of the flange 4 in the axial direction, and an output shaft of the motor 5 passes through the flange 4 to connect with the impeller 1, that is, the motor 5 is used for driving the impeller 1 to rotate on the flange 4 around the self axial direction.

The above embodiments merely illustrate the basic principle and features of the present utility model, and the present utility model is not limited to the above embodiments, but may be varied and altered without departing from the spirit and scope of the present utility model. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. Centrifugal fan, its characterized in that includes:

the impeller (1) is in an annular structure, a first axial end (11) of the impeller (1) is an air inlet of the impeller (1), and the radial outer circumferential surface of the impeller (1) is provided with an air outlet of the impeller (1);

a lower static pressure ring (2), wherein the lower static pressure ring (2) is annularly arranged at a second end (12) of the impeller (1) in the axial direction and extends towards the first end (11) along the axial direction of the impeller (1);

the impeller (1) and the lower static pressure ring (2) are both positioned in the volute (3), and the impeller (1) rotates around the self axial direction relative to the volute (3).

2. Centrifugal fan according to claim 1, wherein the lower static pressure ring (2) is of uniform height in the axial direction of the impeller (1).

3. Centrifugal fan according to claim 1, wherein the height of the lower static pressure ring (2) is not exactly uniform along the axial direction of the impeller (1).

4. Centrifugal fan according to claim 1, characterized in that the centrifugal fan further comprises a flange plate (4), the volute (3) and the lower static pressure ring (2) are both fixed relative to the flange plate (4), and the impeller (1) rotates relative to the flange plate (4).

5. Centrifugal fan according to claim 4, wherein the lower static ring (2) and the volute (3) are provided as an integral structure, which is fixed to the flange (4); or alternatively, the first and second heat exchangers may be,

the lower static pressure ring (2) and the flange plate (4) are arranged as an integral structural member, and the volute (3) is fixed on the flange plate (4).

6. Centrifugal fan according to claim 5, wherein the lower static ring (2) comprises an extension (21) and a connection (22) connected, the extension (21) extending in the axial direction of the impeller (1), and the extension (21) being connected with the volute (3) or the flange (4) by means of the connection (22).

7. Centrifugal fan according to claim 4, further comprising a motor (5), the motor (5) and the impeller (1) being located on both sides of the flange (4) in the axial direction, respectively, and an output shaft of the motor (5) passing through the flange (4) to connect the impeller (1).

8. Centrifugal fan according to claim 4, wherein the distance between the second end (12) and the flange (4) in the axial direction of the impeller (1) is L1,2mm ∈l1 ∈10mm.

9. Centrifugal fan according to claim 1, wherein the distance between the impeller (1) and the lower static pressure ring (2) in the radial direction of the impeller (1) is L2,2mm ∈l2 ∈12mm.

10. Centrifugal fan according to claim 1, wherein the height of the impeller (1) is H1 and the height of the lower static pressure ring (2) is H2, 0.1H1H 2 0.5H1 or less, along the axial direction of the impeller (1).