TWI414684B - Cooling fan - Google Patents

Abstract

A cooling fan includes a frame, an impeller and a coil unit. The frame includes an air inlet and an air outlet, with a channel and a flow-guiding portion being formed therebetween. A transition portion is formed between the channel and the flow-guiding portion. The impeller and coil unit are received in the frame. The impeller defines a central axial line from which the flow-guiding portion of the frame radially extends outwards. The impeller further defines a first reference face and a second reference face. The first reference face extends through a top edge of the impeller and is perpendicular to the central axial line. The second reference face extends through a bottom edge of the impeller and is perpendicular to the central axial line. The transition portion is located between the first reference face and the second reference face. In this arrangement, air flowing is improved and noise is reduced.

Description

Cooling fan

The invention relates to a heat dissipating fan, in particular to an axial flow type cooling fan with a flow guiding portion and an air outlet.

Referring to FIG. 1 , a conventional axial flow type cooling fan 7 is disclosed. The heat dissipation fan 7 includes a frame 71 , a fan wheel 72 , and a motor 73 . The fan frame 71 defines a pair of air inlets 711 and an air outlet 712 in the axial direction, and a fan base 713 is disposed inside the fan frame 71; the fan wheel 72 is rotatably coupled to the inside of the fan frame 71; the motor 73 The base 713 of the fan frame 71 is coupled to drive the fan wheel 72 to rotate to provide a heat dissipation effect.

However, the air outlet 712 of the heat dissipation fan 7 has no structural design that can increase the air flow area and provide a flow guiding function, and is easy to form an unstable flow field and generate improper noise, thereby causing a reduction in heat dissipation effect; therefore, in today's electronic products While the performance is continuously improved, the cooling fan 7 cannot fully meet the actual heat dissipation requirements of the electronic product.

For this reason, please refer to FIG. 2, which is the invention patent of the "Fan and its fan frame" of the Republic of China application No. 200942148. The fan frame 81 used in the conventional cooling fan 8 has a passage 811, and the passage 811 An air inlet 812 and an air outlet 813 are respectively formed at two ends; and the fan frame 81 is adjacent to the air outlet 813 to form a flow guiding portion 814 extending radially outward; thereby, when the fan frame is disposed When one of the inner fan wheels 82 is rotated, the air outlet 813 can increase the airflow area of the airflow by the flow guiding portion 814 to improve the heat dissipation effect of the conventional heat dissipation fan 8.

Referring to FIG. 2 again, the portion of the conventional heat dissipation fan 8 that is adjacent to the flow guiding portion 814 is a turning portion (C) adjacent to the air outlet 813. The peripheral circumference of the opening, in other words, the conventional design of the cooling fan 8 will easily cause the depth (d1) of the passage 811 in the axial direction to be much larger than the depth (d2) of the flow guiding portion 814 in the axial direction; therefore, it is easy to cause During the process of the airflow passing through the air inlet 812, the fan wheel 82 sequentially passes through the channel 811 and the flow guiding portion 814. The guiding portion 814 can be used to guide the airflow effect to be rather limited, and the airflow area cannot be effectively improved. Further, the airflow is more likely to concentrate between the passage 811 and the fan wheel 82, so that the fan wheel 82 may generate a large wind-cut noise during the process of guiding the airflow, so that it is necessary to improve.

The object of the present invention is to improve the shortcomings of the above-mentioned conventional cooling fan, and to provide a cooling fan which can further improve the flow guiding effect of the air outlet.

Another object of the present invention is to provide a heat dissipation fan which can effectively reduce wind noise.

The heat dissipation fan according to the present invention comprises: a frame having an air inlet and an air outlet, wherein a channel and a flow guiding portion are formed between the air inlet and the air outlet, the channel and the guiding portion are disposed on the fan a portion of the inner peripheral wall of the frame adjacent to each other forms a turning portion; a fan wheel rotatably couples the inside of the fan frame; and a coil group disposed inside the fan frame for driving the fan wheel to rotate; wherein the fan wheel Defining a central axis, the flow guiding portion of the fan frame is radially outwardly expanded with respect to the central axis, and the fan wheel is further defined with a first reference And a second reference surface, the first reference surface passes through a top edge of the fan wheel and is perpendicular to the central axis, the second reference surface passes through a bottom edge of the fan wheel and is perpendicular to the central axis, and the turning portion is located Between the first reference surface and the second reference surface; wherein the air inlet and the air outlet respectively have a maximum diameter, and a ratio of a maximum diameter of the air outlet to a maximum diameter of the air inlet is 1.2 to 1.9.

The above and other objects, features, and advantages of the present invention will become more apparent from the claims. The heat dissipation fan 1a of the first embodiment of the present invention includes at least one frame 11, a fan wheel 12, and a coil group 13. The fan frame 11 can be a frame of an axial fan; the fan wheel 12 is rotatably coupled to the inside of the fan frame 11; the coil assembly 13 is disposed inside the fan frame 11 for driving the fan wheel 12 Rotate.

The fan frame 11 is formed in the axial direction with respect to one of the air inlets 111 and one of the air outlets 112, and the fan frame 11 is internally provided with a base 113. The base 113 can be connected by a plurality of connecting members 114 (such as ribs or vanes) The inner peripheral wall of the fan frame 11 is connected, and the base 113 is provided with a shaft connecting portion 115. Further, a passage 116 and a flow guiding portion 117 are formed between the air inlet 111 and the air outlet 112 of the fan frame 11. The passage 116 is adjacent to the air inlet 111, and the flow guiding portion 117 is adjacent to the air outlet 112. The passage 116 and the flow guiding portion 117 form a turning portion (C) at a portion adjacent to the inner peripheral wall of the fan frame 11. .

The fan wheel 12 has a hub 121. The outer circumference of the hub 121 is provided with a plurality of blades 122. The hub 121 of the fan wheel 12 rotatably couples the shaft portion 115 of the base 113.

The coil assembly 13 is disposed inside the base 113 of the fan frame 11 to drive the rotation of the fan wheel 12.

Referring to FIG. 4, the main technical feature of the heat dissipation fan 1a according to the first embodiment of the present invention is that the fan wheel 12 defines a central axis (L), and the flow guiding portion 117 of the fan frame 11 is centered on the central axis. (L) is radially outwardly expanded for reference; wherein the fan wheel 12 defines a first reference plane (S1) and a second reference plane (S2), the first reference plane (S1) passing the top of the fan wheel 12 The edge is perpendicular to the central axis (L), the second reference surface (S2) passes toward the bottom edge of the fan wheel 12 and is perpendicular to the central axis (L); again, the channel 116 and the flow guiding portion 117 are mutually The adjacent turning portion (C) is located between the first reference surface (S1) and the second reference surface (S2).

With the above technical features, it is ensured that the turning portion (C) does not excessively approach the air outlet 112, in other words, the height of the air guiding portion 117 in the axial direction will ensure that the fan wheel 12 is introduced into the airflow through the air inlet. After the passage 116 passes through the passage 116 and enters the flow guiding portion 117, the flow guiding portion 117 can more effectively achieve the effect of guiding the airflow, and can also improve the airflow area; further, the cooling fan 1a of the present invention further It is possible to prevent the airflow from being excessively concentrated between the passage 116 and the fan wheel 12, so that the fan wheel 12 does not generate a large wind-cut noise during the process of guiding the airflow.

Referring to FIG. 5, the cooling fan 1b of the second embodiment of the present invention also includes at least one frame 11, a fan wheel 12, and a coil group 13. The difference between the cooling fan 1b of the second embodiment of the present invention and the cooling fan 1a of the first embodiment is that the fan wheel 12 is further defined between the first reference surface (S1) and the second reference surface (S2). a third reference plane (S3), the third reference plane (S3) is perpendicular to the central axis (L), and the distance from the third reference plane (S3) to the first reference plane (S1) is equal to the The distance from the third reference surface (S3) to the second reference surface (S2); in this embodiment, the transition portion (C) adjacent to the channel 116 and the flow guiding portion 117 is located on the first reference surface ( S1) and the third reference plane (S3).

With the above technical features, the height of the flow guiding portion 117 of the cooling fan 1b of the second embodiment in the axial direction will be greater than the height of the flow guiding portion 117 of the cooling fan 1a of the first embodiment in the axial direction, and thus Providing a better guiding airflow effect; however, to ensure that when the fan wheel 12 introduces airflow into the channel 116, the channel 116 can still provide a predetermined pressure accumulating effect; therefore, the embodiment further defines the turning portion (C) The third reference surface (S3) has a first axial distance (d1), and the third reference surface (S3) has a second axial distance (d2) to the first reference surface (S1). An axial distance (d1) is less than or equal to one-half of the second axial distance (d2) to prevent the turning portion (C) from excessively approaching the air inlet 111, thereby affecting the pressure accumulating effect of the passage 116.

Referring to FIG. 6, the heat dissipation fan 1c of the third embodiment of the present invention also includes at least one frame 11, a fan wheel 12, and a coil group 13. The difference between the heat dissipation fan 1c of the third embodiment of the present invention and the heat dissipation fan 1a of the first embodiment is that the fan wheel 12 is also defined with a third reference surface (S3) perpendicular to the center. Axis (L), and The distance from the third reference surface (S3) to the first reference surface (S1) is equal to the distance from the third reference surface (S3) to the second reference surface (S2); in this embodiment, the channel 116 and The turning portion (C) adjacent to each other of the flow guiding portion 117 is located on the third reference surface (S3).

With the above technical feature, the turning portion (C) of the heat radiating fan 1c of the third embodiment is located on the third reference surface (S3) as compared with the heat radiating fan 1a of the first embodiment; After the fan wheel 12 introduces the airflow into the channel 116 through the air inlet 111, the pressure accumulation effect provided by the channel 116, and the guide wheel 117 provide the airflow into the flow guiding portion 117, the guide portion 117 provides The diversion effect will be more balanced to avoid turbulence, and the heat dissipation effect of the cooling fan 1c can be improved.

Moreover, as shown in Figures 4, 5, and 6, the air inlet 111 of the cooling fan 1a, 1b, 1c of the present invention has a maximum diameter (D1), and the air outlet 112 also has a maximum aperture (D2); The above-mentioned turning portion (C) of the present invention is located under the technical concept between the first reference surface (S1) and the second reference surface (S2), and the maximum aperture (D2) of the air outlet 112 is opposite to the air inlet 111. The ratio of the maximum aperture (D1) may be 1.2 to 1.9, preferably 1.7, whereby the overall airflow area can be more effectively improved.

It can be seen from the above that the cooling fans 1a, 1b, and 1c of the present invention can achieve the effect of improving the flow of the air outlet 112 and effectively reducing the wind noise and the like, so as to provide a more complete cooling fan structure.

Although the present invention has been disclosed by the above-described preferred embodiments, it is not intended to limit the invention, and those skilled in the art may The scope of the invention is to be construed as being limited by the scope of the appended claims.

〔this invention〕

1a, 1b, 1c‧‧‧ cooling fan

11‧‧‧Fan frame

111‧‧‧Air inlet

112‧‧‧air outlet

113‧‧‧Base

114‧‧‧Connecting parts

115‧‧‧Axis joint

116‧‧‧ channel

117‧‧‧Drainage Department

12‧‧‧fan wheel

121‧‧·wheels

122‧‧‧ blades

13‧‧‧ coil set

[study]

7‧‧‧ cooling fan

71‧‧‧Fan frame

711‧‧‧ inlet

712‧‧‧air outlet

713‧‧‧Base

72‧‧‧fan wheel

73‧‧‧Motor

8‧‧‧ cooling fan

81‧‧‧Fan frame

811‧‧‧ channel

812‧‧‧air inlet

813‧‧‧air outlet

814‧‧‧Drainage Department

82‧‧‧fan wheel

Figure 1: A cross-sectional view of a first conventional cooling fan.

Figure 2: A cross-sectional view of a second conventional cooling fan.

Fig. 3 is an exploded perspective view showing the heat radiating fan of the first embodiment of the present invention. Combined sectional view.

Fig. 4 is a sectional view showing the combination of the heat radiating fan of the first embodiment of the present invention.

Fig. 5 is a sectional view showing the combination of the heat radiating fan of the second embodiment of the present invention.

Figure 6 is a sectional view showing the combination of the heat radiating fan of the third embodiment of the present invention.

1a. . . Cooling fan

11. . . Fan frame

111. . . Air inlet

112. . . Air outlet

113. . . Pedestal

114. . . Connector

115. . . Shaft joint

116. . . aisle

117. . . Diversion department

12. . . Fan wheel

121. . . Wheel hub

122. . . blade

13. . . Coil set

Claims (5)

A cooling fan includes: a frame having an air inlet and an air outlet, wherein a channel and a flow guiding portion are formed between the air inlet and the air outlet, and the channel and the guiding portion are inside the fan frame a portion of the peripheral wall adjacent to each other forms a turning portion; a wheel is rotatably coupled to the inside of the frame; and a coil set is disposed inside the frame for driving the fan wheel to rotate; wherein the fan defines a center An axis, the flow guiding portion of the fan frame is radially outwardly expanded with respect to the central axis, the fan wheel further defining a first reference surface and a second reference surface, the first reference surface passing the top edge of the fan wheel And perpendicular to the central axis, the second reference surface passes through the bottom edge of the fan wheel and is perpendicular to the central axis, and the turning portion is located between the first reference surface and the second reference surface; wherein the air inlet and the air inlet The air outlets respectively have a maximum diameter, and the ratio of the largest diameter of the air outlet to the maximum diameter of the air inlet is 1.2 to 1.9. The heat dissipation fan of claim 1, wherein the fan wheel further defines a third reference surface, the third reference surface being located between the first reference surface and the second reference surface, the third reference surface The distance from the third reference surface to the first reference surface is equal to the distance from the third reference surface to the second reference surface, and the turning portion is located on the first reference surface and the third reference surface between. The heat dissipation fan of claim 2, wherein the turning portion to the third reference mask has a first axial distance, the third reference The first reference mask has a second axial distance that is less than or equal to one-half of the second axial distance. The heat dissipation fan of claim 1, wherein the fan wheel further defines a third reference surface, the third reference surface being located between the first reference surface and the second reference surface, the third reference surface The distance from the third reference surface to the first reference surface is equal to the distance from the third reference surface to the second reference surface, and the turning portion is located on the third reference surface. According to the heat dissipation fan of claim 1, wherein the ratio of the maximum diameter of the air outlet to the maximum diameter of the air inlet is 1.7.