CN110017293B

CN110017293B - Centrifugal fan

Info

Publication number: CN110017293B
Application number: CN201910185722.1A
Authority: CN
Inventors: 张雅婷; 黄祥荣
Original assignee: Delta Electronics Inc
Current assignee: Delta Electronics Inc
Priority date: 2014-11-25
Filing date: 2014-11-25
Publication date: 2021-07-30
Anticipated expiration: 2034-11-25
Also published as: CN105697396A; CN110017293A; US20160146216A1

Abstract

A centrifugal fan comprises a fan frame, an impeller and a motor. The fan frame is provided with a bottom plate, a side wall and a plurality of flow deflectors. The side wall and the guide vanes are arranged on the bottom plate. The bottom plate, the side wall and the plurality of flow deflectors form an accommodating space and an air outlet together. The impeller is arranged in the accommodating space, and a flow passage is formed between the impeller and the side wall. The motor is connected with the impeller and drives the impeller to rotate. Wherein the flow deflectors are arranged along the extending direction of the flow channel and sequentially face the air outlet at intervals, and the distance between the flow deflector closer to the air outlet and the impeller is larger.

Description

Centrifugal fan

The invention relates to a divisional application of an invention patent application with the Chinese application number of 201410689760.8, the application date of 2014 being 11/25 and the name of the invention being 'centrifugal fan'.

Technical Field

The present invention relates to a centrifugal fan, and more particularly, to a centrifugal fan capable of increasing an air inlet amount and making an air outlet amount more uniform.

Background

In recent years, with the development of technology, electronic products (such as notebook computers) are gradually developed towards high performance, high speed and high frequency, which causes the operation burden of internal components of the electronic products to be greatly increased, and the heating temperature of the electronic products to be higher and higher, if the electronic products cannot be effectively cooled, the stability of the electronic products will be affected, and even the service life of the electronic products will be shortened.

Fig. 1 is a top view of a conventional centrifugal fan 1, as shown in fig. 1, the conventional centrifugal fan 1 has an air outlet O1 and an air inlet (not shown), and a sidewall 11 is disposed beside a flow passage P1 of the centrifugal fan 1. Since the surface of the sidewall 11 facing the flow passage P1 is a continuous and closed plane, the air inlet amount of the centrifugal fan 1 is mainly limited by the size and position of the air inlet, and is difficult to be greatly increased. In addition, the centrifugal fan 1 shown in fig. 1 also has a problem of uneven air output, which is concentrated in the strong wind region H.

In order to solve the above problems, centrifugal fans different from the above structure have been proposed, and fig. 2 is a top view of another conventional centrifugal fan 2. Centrifugal fan 2 has bottom plate 21, lateral wall 22 and air inlet structure 23. The air intake structure 23 includes an air inlet 231 and an air guiding plate 232. The air inlet 231 is disposed on the side wall 22, the air guiding sheet 232 is disposed on a side of the air inlet 231, and the air guiding sheet 232 extends toward the flow passage P2. Although the purpose of the air inlet 231 is to help increase the air inlet volume of the centrifugal fan 2, the air guiding sheet 232 occupies a part of the original air channel P2, so that the air flow channel P2 is limited in space, and thus, in actual practice, the air volume inside the centrifugal fan 2 cannot be actually increased. In addition, the above structure causes the centrifugal fan 2 to have the problems of large and small internal wind pressure, poor fan characteristics, large operation noise and the like. Furthermore, when dust inside the centrifugal fan 2 or dust outside the centrifugal fan 2 is blown to the air inlet structure 23, the dust is easily accumulated on the flow guide portions 2321 of the air guide pieces 232, so that wind resistance near the air inlet 231 is increased, and it is difficult for external air flow to enter the centrifugal fan 2 through the air inlet 231.

In view of the above, in addition to the recent trend toward thinner electronic devices, the thinner electronic devices will be compressed into the internal space, so how to provide a centrifugal fan capable of effectively increasing the air intake amount and making the air output amount more uniform without increasing the volume is one of the important issues at present.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a centrifugal fan capable of increasing an intake air volume efficiently and making an output air volume more uniform without increasing a volume.

To achieve the above objective, a centrifugal fan according to the present invention includes a fan frame, an impeller, and a motor. The fan frame is provided with a bottom plate, a side wall and a plurality of flow deflectors. The side wall and the guide vanes are arranged on the bottom plate. The bottom plate, the side wall and the plurality of flow deflectors form an accommodating space and an air outlet together. The impeller is arranged in the accommodating space, and a flow passage is formed between the impeller and the side wall. The motor is connected with the impeller and drives the impeller to rotate. The guide vanes are arranged along the extending direction of the flow channel and sequentially face the air outlet at intervals, and the distance between the guide vanes and the impeller, which are closer to the air outlet, is larger.

In one embodiment, any two adjacent guide vanes partially overlap in a predetermined direction.

In one embodiment, the predetermined direction is perpendicular to a tangential direction of rotation of the impeller.

In an embodiment, the plurality of flow deflectors at least include a first flow deflector and a second flow deflector, a distance between the second flow deflector and the air outlet is smaller, and the second flow deflector and the impeller are respectively disposed on two opposite sides of the first flow deflector.

In one embodiment, a gap is formed between any two adjacent guide vanes, an external air flow flows into the centrifugal fan from the gap, and the flow direction of the external air flow is along the extending direction of the flow channel.

In one embodiment, the sidewall has a throat portion, and the throat portion and the plurality of flow deflectors are respectively disposed on two opposite sides of the impeller.

In an embodiment, the plurality of flow deflectors are arc-shaped.

In one embodiment, when the motor drives the impeller to rotate reversely, dust inside the centrifugal fan is discharged out of the centrifugal fan from between any two adjacent guide vanes.

In view of the above, the centrifugal fan of the present invention has the flow deflectors arranged along the extending direction of the flow channel and spaced toward the air outlet, so that the external air flow can flow into the fan from between two adjacent flow deflectors, thereby achieving the effect of increasing the inlet air volume. In addition, the air flow flowing into the fan can flow to the air outlet along the flow deflector, so that the air outlet volume is more uniform.

Drawings

Fig. 1 is a plan view of a conventional centrifugal fan.

Fig. 2 is a top view of another prior art centrifugal fan.

Fig. 3A is an exploded view of a centrifugal fan according to a preferred embodiment of the invention.

Fig. 3B is a top view of the centrifugal fan shown in fig. 3A.

Fig. 3C is a schematic view of the centrifugal fan reversing.

Fig. 4 is a schematic view of a variation of the guide vane of the present invention.

Wherein the reference numerals are as follows:

1. 2, 3, 4: centrifugal fan

11. 22: side wall

21. 311: base plate

23: air inlet structure

231: air inlet

232: air guide sheet

2321: drainage part

31: fan frame

312: side wall

3121: throat part

3122: flow guiding part

313. 3131, 3132, 313 a: flow deflector

3131 a: first end

3131 b: second end

3132 a: third terminal

3132 b: fourth terminal

314: top board

32: impeller

321: wheel hub

322: fan blade

33: motor with a stator having a stator core

D: gap

d: distance between two adjacent plates

d1, d 2: direction of rotation

d 3: preset direction

H: strong wind zone

O1, O2: air outlet

O3: air inlet

P1, P2, P3: flow passage

S: containing space

Detailed Description

A centrifugal fan according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings, in which like elements are described with like reference numerals.

Fig. 3A is an exploded view of a centrifugal fan 3 according to a preferred embodiment of the present invention, and fig. 3B is a top view of the centrifugal fan 3 shown in fig. 3A. For simplicity of illustration, the top plate 314 of FIG. 3A is omitted from FIG. 3B for ease of understanding. Referring to fig. 3A and fig. 3B, in the present embodiment, the centrifugal fan 3 includes a fan frame 31, an impeller 32, and a motor 33. The centrifugal fan 3 may be disposed in an electronic product as a heat dissipation system of the electronic product. The electronic product may be a notebook computer, for example.

The fan frame 31 has a bottom plate 311, a sidewall 312 and a plurality of guide vanes 313. In the embodiment, the centrifugal fan 3 has three flow deflectors 313 as an example, however, the number of the flow deflectors 313 is not limited in the invention, and the number of the flow deflectors 313 can be adjusted according to actual requirements.

The sidewalls 312 and the plurality of baffles 313 are disposed on the bottom plate 311. The bottom plate 311, the side wall 312 and the plurality of baffles 313 together form an accommodating space S and an air outlet O2.

The impeller 32 includes a hub 321 and a plurality of blades 322, the impeller 32 is disposed in the accommodating space S and sleeved on the motor 33, and the motor 33 is connected to the impeller 32 and drives the impeller 32 to rotate. A flow path P3 (fig. 3B) is formed between the impeller 32 and the sidewall 312. In the present embodiment, the fan frame 31 further includes a top plate 314, and the top plate 314 has an air inlet O3. When the impeller 32 is operated, the external air flow flows into the centrifugal fan 3 from the air inlet O3, flows to the air outlet O2 along the flow path P3, and is then exhausted from the air outlet O2.

In the present embodiment, the flow deflectors 313 are sequentially disposed along the extending direction of the flow path P3 and are spaced toward the air outlet O2. In detail, the sidewall 312 of the present embodiment has a throat portion 3121 and a flow guiding portion 3122, and the throat portion 3121 and the flow guiding portion 3122 are respectively located at two ends of the sidewall 312. The baffles 313 are sequentially spaced from the position adjacent to the flow guide portion 3122 toward the air outlet O2, and the baffles 313 and the throat portion 3121 are respectively disposed on opposite sides of the impeller 32. Since the guide vanes 313 are spaced apart from each other, a gap D is formed between any two adjacent guide vanes 313. In the present embodiment, the distance D of the gap D is preferably between 0.5 mm and 10 mm. Therefore, when the impeller 32 is operated, the external air flow can flow into the centrifugal fan 3 from the gap D and flow along the extending direction of the flow passage P3, thereby achieving the effect of increasing the inlet air volume.

In the present embodiment, the flow deflectors 313 can guide the external airflow flowing into the centrifugal fan 3 to the original position with smaller air output, taking fig. 3B as an example, the external shape of the flow deflector 313 is arc-shaped, and the external airflow can be guided by the flow deflector 313 to a position closer to the center point of the air outlet O2, so that the air output near the air outlet O2 is more uniform. It is specifically noted that the shape of the baffle 313 can be adjusted according to the flow guiding requirement of the fan, and is not limited to the shape shown in the drawings.

The relative positions of the guide vanes 313 will be described in detail below.

In the present embodiment, the flow guiding plates 313 include at least a first flow guiding plate 3131 and a second flow guiding plate 3132. Compared with the first flow deflector 3131, the distance between the second flow deflector 3132 and the air outlet O2 is smaller. The second flow guiding plate 3132 and the impeller 32 are disposed on two sides of the first flow guiding plate 3131, respectively.

In detail, the first flow guiding plate 3131 has a first end 3131a and a second end 3131b, and the second end 3131b is adjacent to the second flow guiding plate 3132. The second deflector 3132 has a third end 3132a and a fourth end 3132b, wherein the third end 3132a is adjacent to the first deflector 3131. The third end 3132a and the impeller 32 are disposed at two sides of the second end 3131b, respectively. That is, the second guide vane 3132 is disposed outside the first guide vane 3131.

In the centrifugal fan 3 of the present embodiment, the guide plates 313 located closer to the air outlet O2 are located at outer sides, so that the guide plates 313 are not compressed into the space of the entire flow channel, and the compression of the air volume inside the centrifugal fan 3 can be avoided.

In addition, in the present embodiment, two adjacent guide vanes 313 partially overlap in a predetermined direction. For example, the rotation direction of the impeller 32 is a direction d1, the tangential component thereof is a direction d2, the predetermined direction d3 is perpendicular to the direction d2, and the first guide vane 3131 and the second guide vane 3132 are partially overlapped in the predetermined direction d 3. In this way, when the impeller 32 is running in the forward direction, the airflow inside the centrifugal fan 3 can be prevented from escaping from the gap D between the first guide vane 3131 and the second guide vane 3132.

In the present embodiment, a gap D is also formed between the first end 3131a of the first deflector 3131 and the flow guide portion 3122, and the gap D can increase the amount of the incoming air. The distance between the first flow guiding plate 3131 and the impeller 32 is greater than the distance between the side wall 312 and the impeller 32, so that the first flow guiding plate 3131 is prevented from being compressed into the flow passage space.

As a whole, the distance between the side wall 312 and the impeller 32, the distance between the first guide vane 3131 and the impeller 32, and the distance between the second guide vane 3132 and the impeller 32 are sequentially increased to make the width of the entire flow passage wider and wider, so that there is enough space inside the centrifugal fan 3 for the external airflow flowing from the gap D to flow, so as to increase the air volume inside the centrifugal fan 3.

In addition, in the embodiment, when the motor 33 (as shown in fig. 3A) drives the impeller 32 to rotate reversely, as shown in fig. 3C, fig. 3C is a schematic diagram illustrating that the centrifugal fan 3 rotates reversely, a reverse airflow is generated inside the centrifugal fan 3, and the dust inside the centrifugal fan 3 can be discharged out of the centrifugal fan 3 from the gap D between any two adjacent guide vanes along the reverse airflow, thereby achieving the effect of reverse dust removal. Since the guide vane 313 is in a corresponding arc shape with the flow direction of the flow field, the dust inside the centrifugal fan 3 can be discharged from the gap D along the arc shape of the guide vane 313.

Fig. 4 is a schematic view of a variation of a flow deflector of the present invention, and please refer to fig. 4, which is different from the flow deflector 313 in that the flow deflector 313a shown in fig. 4 is approximately rectangular in shape from a top view, and the rest of the related contents are substantially the same as those of the previous embodiment.

In summary, in the centrifugal fan of the present invention, the flow deflectors are disposed along the extending direction of the flow channel and spaced toward the air outlet, so that the external air flow can flow into the fan from between two adjacent flow deflectors, thereby achieving the effect of increasing the inlet air volume. In addition, the air flow flowing into the fan can flow to the air outlet along the flow deflector, so that the air outlet volume is more uniform.

Compared with the prior art, the flow channel of the centrifugal fan can not be compressed due to the arrangement of the flow deflector, and the centrifugal fan can further avoid the problem that the air pressure in the fan is suddenly large and suddenly small, so that the fan characteristic is improved and the running noise is reduced. In addition, the dust in the fan can be smoothly discharged without accumulating at the position of the gap.

The foregoing is by way of example only, and not limiting. It is intended that all equivalent modifications or variations not departing from the spirit and scope of the present invention shall be included in the appended claims.

Claims

1. A centrifugal fan, comprising:

the fan frame is provided with a bottom plate, a side wall and a plurality of flow deflectors, wherein the side wall and the plurality of flow deflectors are arranged on the bottom plate, and the bottom plate, the side wall and the plurality of flow deflectors jointly form an accommodating space and an air outlet;

the impeller is arranged in the accommodating space, and a flow channel is formed between the impeller and the side wall; and

a motor connected with the impeller and driving the impeller to rotate,

the guide vanes are arranged along the extending direction of the flow channel and sequentially face the air outlet at intervals, and the distance between the guide vane and the impeller, which is closer to the air outlet, is larger, so that the width of the whole flow channel, which is closer to the air outlet, is wider; and

wherein a gap is formed between any two adjacent guide vanes;

the plurality of flow deflectors at least comprise a first flow deflector and a second flow deflector, the distance between the second flow deflector and the air outlet is smaller, and the second flow deflector and the impeller are respectively arranged on two opposite sides of the first flow deflector;

the distance between the side wall and the impeller, the distance between the first flow deflector and the impeller, and the distance between the second flow deflector and the impeller are sequentially increased, so that the width of the whole flow channel is increased.

2. The centrifugal fan as claimed in claim 1, wherein any two adjacent guide vanes partially overlap in a predetermined direction.

3. The centrifugal fan of claim 2, wherein the predetermined direction is perpendicular to a tangential direction of rotation of the impeller.

4. The centrifugal fan as described in claim 1, wherein an external air flow flows into the centrifugal fan from the gap, and the flow direction of the external air flow is along the extending direction of the flow channel.

5. The centrifugal fan as claimed in claim 1, wherein the sidewall has a throat portion, and the throat portion and the plurality of guide vanes are respectively disposed at opposite sides of the impeller.

6. The centrifugal fan of claim 1, wherein the plurality of baffles are arcuate.

7. The centrifugal fan of claim 1, wherein dust inside the centrifugal fan is discharged out of the centrifugal fan from between any two adjacent guide vanes when the motor drives the impeller to rotate in reverse.