TW201540961A - Centrifugal fan - Google Patents

Abstract

A centrifugal fan includes a housing and an impeller. The housing includes a first sidewall, a second sidewall opposite to the first sidewall, an arc sidewall and a tongue portion. The arc sidewall is connected to the first sidewall and the second sidewall. The tongue portion is disposed at the first sidewall, and opposite to the arc sidewall. The impeller is located between the arc sidewall and the tongue portion. A length of the tongue portion from an end of the tongue portion to another end of the tongue portion adjacent to the first sidewall is greater than the radius of the impeller.

Description

Centrifugal fan

The invention relates generally to a fan, and more particularly to a centrifugal fan.

Due to the trend of thinning electronic products, the thickness of fans in electronic products is limited. However, as the thickness of the fan is reduced, the problem of the wind pressure and the amount of airflow is also reduced. For example, the height of the blades is reduced, reducing the amount of air that can be pushed. In addition, the structure of the blade is also weakened, and it is difficult to push more airflow by increasing the length of the blade.

Therefore, the fan must be redesigned and improved to provide sufficient wind pressure and air output to dissipate the interior of the electronic product in the case of thinner and thinner thickness.

In order to solve the above-mentioned deficiencies of the prior art, it is an object of the present invention to provide a centrifugal fan which can provide sufficient wind pressure and air output in a thinned condition.

In order to achieve the above object, the present invention provides a centrifugal fan including a housing and an impeller. The housing includes a first side wall, a second side wall opposite the first side wall, an arcuate side wall, and a tongue. The curved side wall is coupled to the first side wall and the second side wall. The tongue is disposed on the first side wall and opposite to the curved side wall. The impeller is disposed between the arcuate side wall and the tongue. The tongue is from one end of the tongue to adjacent to the above The length of the other end of the first side wall is greater than the radius of the impeller.

In summary, the centrifugal fan of the present invention can increase the wind pressure of the centrifugal fan by increasing the length of the spiral passage, and can stabilize the flow field of the airflow in the casing, thereby increasing the outflow of the centrifugal fan. The air volume and the reduced airflow flow back through the axial air inlet to the outside of the housing.

1‧‧‧ centrifugal fan

10‧‧‧shell

11‧‧‧floor

12‧‧‧First side wall

13‧‧‧Second side wall

14‧‧‧ curved side walls

141‧‧‧ curved side

15‧‧ ‧Tongue

151‧‧‧

152‧‧‧ curved surface

16‧‧‧ Cover

20‧‧‧ Impeller

21‧‧·wheels

22‧‧‧ fan leaves

30‧‧‧Heat unit

31‧‧‧ Heat sink fins

40‧‧‧Thin heat pipe

A1‧‧‧ axial air inlet

A2‧‧‧radial air outlet

A3‧‧‧Connected

A4‧‧‧ perforation

Ax1‧‧‧Rotary axis

B1‧‧‧ junction

C1‧‧‧ spiral channel

C2‧‧‧Out of the air space

D1‧‧‧Arranged direction

D2‧‧‧ extending direction

E1‧‧‧ first interface

E2‧‧‧ second interface

F1‧‧‧ angle

R1‧‧‧ radius

T1‧‧‧ thickness

W1, W2‧‧‧ width

Fig. 1 is a perspective view of a centrifugal fan of the present invention.

Fig. 2 is an exploded view of the centrifugal fan of the first embodiment of the present invention.

Fig. 3 is a plan view showing a centrifugal fan according to a first embodiment of the present invention.

Fig. 4 is a plan view showing a centrifugal fan according to a second embodiment of the present invention.

Fig. 5 is a perspective view of a centrifugal fan according to a second embodiment of the present invention.

Fig. 6 is a plan view showing a centrifugal fan according to a third embodiment of the present invention.

Fig. 1 is a perspective view of a centrifugal fan 1 of the present invention. Fig. 2 is an exploded view of the centrifugal fan 1 of the first embodiment of the present invention. Fig. 3 is a plan view showing the centrifugal fan 1 of the first embodiment of the present invention. The centrifugal fan 1 can be a thin centrifugal fan 1, which can be disposed in a thin electronic device such as an ultra-thin notebook computer, a tablet computer, or a smart mobile phone.

The centrifugal fan 1 includes a casing 10, an impeller 20, a heat radiating unit 30, and a thin heat pipe 40. The housing 10 has an axial air inlet A1 and a radial air outlet A2. In this embodiment, the axial air inlet A1 is located on one of the top surfaces of the housing 10, and the radial air outlet A2 is located in one of the housings 10. side. In addition, the axial air inlet A1 may be a circular shape, and the radial air outlet A2 may be an elongated shape. impeller 20 is disposed in the housing 10 and corresponds to the axial air inlet A1.

The heat dissipation unit 30 is disposed at the radial air outlet A2. The heat dissipation unit 30 includes a plurality of heat dissipation fins 31 which are disposed at intervals along the arrangement direction D1 at the radial air outlet A2. The thin heat pipe 40 contacts the heat radiating unit 30, and one end of the thin heat pipe 40 can be connected to a heat source (not shown). In another embodiment, the centrifugal fan 1 may not include the heat dissipation unit 30 and/or the thin heat pipe 40.

The impeller 20 is rotatable about a rotation axis Ax1. The rotation axis Ax1 passes through the radial air outlet A2. When the impeller 20 rotates, the impeller 20 draws air from the axial air inlet A1 into the casing 10, and discharges the air in the casing 10 through the radial air outlet A2. In the present embodiment, the impeller 20 can include a hub 21 and a plurality of blades 22 . The blades 22 are radially arranged on the side wall of the hub 21. The height of the blade 22 is between about 2.5 mm and 4 mm, and the length of the blade 22 is between about 10 mm and 20 mm.

The thickness T1 of the casing 10 is between about 3 mm and 5 mm. The housing 10 includes a bottom plate 11, a first side wall 12, a second side wall 13, an arcuate side wall 14, a tongue portion 15, and a cover plate 16 (not shown in Fig. 3). The bottom plate 11 can be a plate-like structure. The first side wall 12, the second side wall 13, the curved side wall 14, and the tongue portion 15 are disposed on the bottom plate 11 and extend perpendicular to the bottom plate 11.

The first side wall 12 can be located at one edge of the bottom plate 11. The second side wall 13 may be located at the other opposite edge of the bottom plate 11 and opposite to the first side wall 12. In this embodiment, the first sidewall 12 and the second sidewall 13 may have a linear structure and extend along an extending direction D2, but are not limited thereto, wherein the extending direction D2 is perpendicular to the array direction D1. The curved side wall 14 can be located at one edge of the bottom plate 11, and the two ends of the curved side wall 14 are respectively connected to the first side wall 12 and the second side wall 13.

The tongue 15 is disposed on the first side wall 12 and opposite to the curved side wall 14. The impeller 20 is disposed between the curved side wall 14 and the tongue portion 15. One of the lengths of the tongue 15 is about 1 to 4 times the radius r1 of the impeller 20, and the aforementioned length of the tongue 15 is defined as the length from one end 151 of the tongue 15 to the other end adjacent to the first side wall 12. One end 151 of the tongue 15 is adjacent to the impeller 20, and the distance between one end 151 of the tongue 15 and the impeller 20 can be between 1.5 mm and 3 mm. In the present embodiment, the length of the tongue portion 15 is greater than three times the radius r1 of the impeller 20. In another embodiment, the length of the tongue 15 is greater than the radius r1 of the impeller 20 or 1.5 or 2 times the radius r1.

The cover plate 16 may be a plate-like structure that is parallel to the bottom plate 11 and spaced apart from the bottom plate 11. The cover plate 16 is coupled to the first side wall 12, the second side wall 13, the curved side wall 14, and the tongue 15. The axial air inlet A1 may be located in the cover plate 16, and the radial air outlet A2 is formed by the bottom plate 11, the first side wall 12, the second side wall 13, and the cover plate 16. In other words, the axial air inlet A1 can be parallel to the bottom plate 11, and the radial air outlet A2 can be perpendicular to the axial air inlet A1.

As shown in FIG. 3, a first interface E1 is defined between one end 151 of the tongue portion 15 and the rotation axis Ax1, and a boundary between the boundary B1 of the second side wall 13 and the curved side wall 14 and the rotation axis Ax1 is defined. Second interface E2. The first interface E1 and the second interface E2 are each defined as a plane. The first interface E1 and the second interface E2 have an angle F1 corresponding to one of the arcuate sidewalls 14 described above. In other words, the rotation axis Ax1 is located on the boundary B1 of the first interface E1 and the second interface E2.

In some embodiments, the angle F1 can be 235 degrees to 360 degrees, or can be 260 degrees to 360 degrees. Since the first interface E1 and the second interface E2 are located on the same plane in this embodiment, the angle F1 is 360 degrees.

As shown in FIGS. 2 and 3, a communication port A3 is formed between one end 151 of the tongue portion 15 and the second side wall 13. In the present embodiment, the communication port A3 is defined as being located on the shortest path between the one end 151 of the tongue portion 15 and the second side wall 13. In addition, in the embodiment, the communication port A3 is located on the second interface E2, and the communication port A3 may be parallel to the radial air outlet A2, perpendicular to the second side wall 13, and/or perpendicular to the bottom plate 11.

The width W1 of the communication port A3 is between 0.3 and 1 times the diameter of the impeller 20. In the present embodiment, the width W1 of the communication port A3 is smaller than the radius r1 of the impeller 20. In another embodiment, the width W1 of the communication port A3 may be less than 0.4 times, 0.6 times, or 0.8 times the diameter of the impeller 20. Further, the width W1 of the communication port A3 is approximately 0.2 to 0.8 times the width W2 of one of the radial air outlets A2. In the present embodiment, the width W1 of the communication port A3 is about 0.25 times the width W2 of the radial air outlet A2. In another embodiment, the width W1 of the communication port A3 is less than 0.4 times or 0.6 times the width W2 of the radial air outlet A2.

In the present embodiment, the tongue portion 15 has an arcuate surface 152, and the curved surface 152 forms a spiral surface with the curved side surface 141 of the curved side wall 14. Both the curved surface 152 and the curved side 141 face the impeller 20 and correspond to the sidewall of the impeller 20. The helical surface is gradually increased from the one end 151 of the tongue 15 to the boundary B1 from the impeller 20. Therefore, a spiral passage C1 is formed between the spiral surface, the impeller 20, and the communication port A3. In other words, the spiral passage C1 is located between the bottom plate 11, the curved side wall 14, the tongue 15, and the cover plate 16.

In addition, an air outlet space C2 is formed between the bottom plate 11, the first side wall 12, the second side wall 13, the tongue portion 15, the cover plate 16, the radial air outlet A2, and the communication port A3. The tongue 15 is located between the spiral passage C1 and the outlet space C2. by The wind pressure of the airflow generated by the impeller 20 gradually increases in the spiral passage C1, and then the airflow is discharged through the communication port A3 and the air outlet space C2 to the radial air outlet A2.

With the structure of the centrifugal fan 1 described above, the length of the spiral passage C1 can be increased. Due to the increase in the length of the spiral passage C1, the wind pressure of the airflow discharged from the centrifugal fan 1 can be further improved. In addition, due to the increase in the length of the spiral passage C1, the flow field of the airflow in the casing 10 is relatively stable, so that the gas can be smoothly sucked into the casing 10 via the impeller 20, thereby increasing the air volume of the centrifugal fan 1. And wind pressure. The above structure can also reduce the flow of air in the impeller 20 to the outside of the casing 10 via the axial air inlet A1, thereby increasing the air volume and the wind pressure of the centrifugal fan 1.

4 is a plan view of a centrifugal fan 1 according to a second embodiment of the present invention, and FIG. 5 is a perspective view of a centrifugal fan 1 according to a second embodiment of the present invention, in which the cover 16 is omitted for the purpose of clarity of illustration. . The second embodiment is mainly different from the first embodiment in that the length of the tongue portion 15 of the second embodiment is shorter than the length of the tongue portion 15 of the first embodiment, and the tongue portion 15 has a through hole A4.

In the present embodiment, the length of the tongue 15 is greater than the diameter of the impeller 20. The first interface E1 and the second interface E2 are located on different planes, and the angle F1 between the first interface E1 and the second interface E2 is about 315 degrees. The width W1 of the communication port A3 is approximately the radius r1 of the impeller 20. The width W1 of the communication port A3 is about 0.3 times the width W2 of one of the radial air outlets A2.

As shown in FIG. 5, the perforation A4 extends through one of the side walls of the tongue 15 and faces the impeller 20. The perforation A4 is connectable to the spiral passage C1 and the outlet space C2. In this embodiment, the through hole A4 can be located at one end 151 and the bottom of the tongue portion 15, and the height of the through hole A4 is smaller than the height of the tongue portion 15, but is not limited thereto. In another implementation In the example, the perforation A4 can be located in the center of the tongue 15 or at the top of the tongue 15.

With the perforation A4 described above, a part of the airflow flowing out of the impeller 20 can flow directly through the tongue 15 (especially near one end of the tongue 15) to the air outlet space C2 to increase the output of the centrifugal fan 1. The air volume, and the size of the perforation A4 relative to the tongue 15, is small, so that the airflow flowing out of the perforation A4 can maintain sufficient wind pressure. It should be noted that the above-mentioned through hole A4 can also be disposed in other embodiments of the disclosure.

Fig. 6 is a plan view of the centrifugal fan 1 of the third embodiment of the present invention, in which the cover 16 is omitted for the purpose of clarity. The main difference between the third embodiment and the first embodiment is that. The length of the tongue portion 15 of the third embodiment is shorter than the length of the tongue portion 15 of the first embodiment. In the present embodiment, the length of the tongue portion 15 is approximately the radius r1 of the impeller 20. The first interface E1 and the second interface E2 are located on different planes, and the angle F1 between the first interface E1 and the second interface E2 is about 270 degrees. The width W1 of the communication port A3 is approximately the diameter of the impeller 20. The width W1 of the communication port A3 is approximately half the width W2 of the radial air outlet A2.

In summary, the centrifugal fan of the present invention can increase the wind pressure of the centrifugal fan by increasing the length of the spiral passage, and can stabilize the flow field of the airflow in the casing, thereby increasing the outflow of the centrifugal fan. The air volume and the reduced airflow flow back through the axial air inlet to the outside of the housing.

The present invention has been described above with reference to various embodiments, which are intended to be illustrative only and not to limit the scope of the invention, and those skilled in the art can make a few changes without departing from the spirit and scope of the invention. With retouching. The above-described embodiments are not intended to limit the scope of the invention, and the scope of the invention is defined by the scope of the appended claims.

1‧‧‧ centrifugal fan

12‧‧‧First side wall

13‧‧‧Second side wall

14‧‧‧ curved side walls

141‧‧‧ curved side

15‧‧ ‧Tongue

151‧‧‧

152‧‧‧ curved surface

20‧‧‧ Impeller

21‧‧·wheels

22‧‧‧ fan leaves

30‧‧‧Heat unit

40‧‧‧Thin heat pipe

A2‧‧‧radial air outlet

A3‧‧‧Connected

Ax1‧‧‧Rotary axis

C1‧‧‧ spiral channel

C2‧‧‧Out of the air space

D1‧‧‧Arranged direction

D2‧‧‧ extending direction

W1, W2‧‧‧ width

R1‧‧‧ radius

B1‧‧‧ junction

E1‧‧‧ first interface

E2‧‧‧ second interface

F1‧‧‧ angle

Claims (10)

A centrifugal fan includes: a casing comprising: a first side wall; a second side wall opposite to the first side wall; an arcuate side wall connected to the first side wall and the second side wall; a tongue Provided on the first side wall and opposite to the curved side wall; and an impeller disposed between the curved side wall and the tongue portion; wherein the tongue portion is from one end of the tongue portion to adjacent to the first side wall The other end has a length greater than the radius of the impeller. The centrifugal fan according to claim 1, wherein the length is 1 to 4 times the radius of the impeller. The centrifugal fan according to claim 1, wherein the tongue has an arcuate surface, and the arcuate surface forms a spiral surface with one of the arcuate side walls. The centrifugal fan according to claim 1, wherein the impeller rotates around a rotating shaft, a first interface is defined between one end of the tongue and the rotating shaft, and the second sidewall and the arc are A second interface is defined between the boundary of the sidewalls and the rotating shaft, wherein the first interface and the second interface have an angle corresponding to one of the curved sidewalls, and the angle is 235 to 360 degrees. The centrifugal fan according to claim 1, wherein a communication port is formed between one end of the tongue and the second side wall, and the communication port is One of the widths is smaller than a diameter of one of the impellers, wherein the communication port is located on a shortest path between one end of the tongue and the second side wall. The centrifugal fan according to claim 1, wherein a communication port is formed between one end of the tongue and the second side wall, the housing has a radial air outlet, and one of the communication ports has a width smaller than The width of one of the radial air outlets is 0.8 times, wherein the communication port is located on one of the shortest paths between one end of the tongue and the second side wall. The centrifugal fan according to claim 6, further comprising a heat dissipating unit disposed at the radial air outlet. The centrifugal fan of claim 1, wherein the impeller comprises: a hub; and a plurality of blades radially arranged on one side wall of the hub; wherein the height of the blade is about 2.5 mm to 4 mm Between the above, the length of the blade is between about 10 mm and 20 mm, and the thickness of the casing is between about 3 mm and 5 mm. The centrifugal fan according to claim 1, wherein the tongue has a through hole penetrating through a side wall of the tongue and facing the impeller. A centrifugal fan according to claim 9, wherein the perforations are located at one end and the bottom of the tongue.