CN101119627B - Heat dissipation device and its fan frame structure - Google Patents

Abstract

The invention provides a heat dissipation device and a fan frame structure used by the same. The heat dissipation device comprises a fan wheel and a fan frame structure. The impeller includes a hub and a plurality of blades annularly arranged around the hub. The fan frame structure comprises an outer frame; a flow guide part formed on one side of the outer frame; and a plurality of static blades arranged in the outer frame corresponding to the position of the flow guide part and used for guiding the airflow passing through the blades and improving the static pressure of the airflow blown out by the heat dissipation device.

Description

Heat dissipation device and its fan frame structure

This application is a divisional application of Chinese Patent Application No. 03142983.1 with the filing date of June 11, 2003 and the title of the invention is "Heat Dissipation Device and Fan Frame Structure Used therein". the

technical field

The present invention relates to a cooling device and its fan frame structure, in particular to an axial flow fan and its fan frame structure. the

Background technique

In general electronic products (such as computers), since the electronic components in them generate a lot of heat during operation, if they are kept at high temperature, it will easily lead to wear and tear of the electronic components and shorten their lifespan. Therefore, in order to prevent electronic components from malfunctioning, cooling fans are generally provided therein to dissipate the heat generated inside to the outside. the

Conventional computer cooling fans mainly include a fan frame 11 and an impeller 12 with a plurality of blades, and the structure of the fan frame 11 mostly uses rod-shaped ribs 13 to support the base in the fan fan frame, as shown in Figures 1A and 1B. Show. When the fan rotates, the wind pressure of the airflow passing through the blades changes from the wind pressure P0 of the wind inlet side A to the wind pressure P1 of the wind outlet side B, that is, the wind pressure change is ΔP=P1-P0, and the wind pressure change is more A larger value means the greater the resistance of the fan, that is, the worse the heat dissipation effect. Carefully analyzing the influence of the shape of the ribs on the wind pressure of the fan, it will be found that the presence of the ribs will generate wind resistance. Because the rotation of the fan does work on the air to generate airflow, the airflow will form a cyclone due to turbulence after passing through the ribs, resulting in the loss of wind pressure and reducing the heat dissipation efficiency of the fan. the

Therefore, how to reduce the wind resistance generated by the ribs and how to use the tangential velocity of the airflow to increase the wind pressure are the purpose and focus of the development of the present invention. the

In view of the deficiencies of the conventional technology, the present invention finally creates the heat dissipation device of the present invention and the fan frame structure used therefor through careful experiments and researches and a persistent spirit. the

Contents of the invention

The main purpose of the present invention is to provide a cooling fan and the fan frame structure used therein, which utilizes the change of the stationary vanes and the area on the fan frame, and reduces the speed in the axial and radial directions at the same time, so as to greatly increase the fan performance. static pressure. the

Another object of the present invention is to provide a heat dissipation device and its fan frame structure, which can provide performances of low noise, high air volume and high air pressure, thereby achieving a better heat dissipation effect. the

According to the idea of the present invention, the heat dissipation device includes a fan wheel and a fan frame structure. The fan wheel includes a hub and a plurality of blades arranged around the hub. The fan frame structure is used to accommodate the fan wheel, which includes an outer frame; a guide part formed on one side of the outer frame; The outer frame is used to guide the airflow flowing through the blades and increase the static pressure of the airflow blown out by the cooling device. the

Preferably, the outer diameter of the hub can be gradually reduced from one end to the other end of the hub. the

Preferably, the air guide part is located on the air inlet side or the air outlet side of the fan frame structure. the

Preferably, the depth of the guide part is greater than half of the height of the vane. Alternatively, the height of the vane is preferably greater than one-fifth of the thickness of the outer frame. the

Wherein, the vane is arranged at the position of the guide part in the outer frame. the

Preferably, the outer frame is a square, rectangular or circular frame. Its material can be metal or plastic. the

In addition, the heat dissipation device further includes a base connected to the outer frame by the plurality of vanes or ribs. Preferably, one end of the plurality of vanes is connected to the base, and the other free end extends toward the flow guiding portion. Alternatively, one end of the plurality of vanes is connected to the guide part, and the other free end extends toward the base. Alternatively, the plurality of vanes are radially arranged and connected between the base and the inner surface of the outer frame. In addition, the outer frame, the base, the flow guiding part and the plurality of vanes can be made by integral injection molding. the

And the air guide part can be formed on the wind inlet side or the wind outlet side of the outer frame. If the air guiding parts are respectively formed on the air inlet side and the air outlet side of the outer frame, the two air guiding parts can also be symmetrically arranged as mirror images. the

To sum up the above, the heat dissipation device and its fan frame structure provided by the present invention use the vanes on the fan frame and the change in area, while reducing the axial and radial speeds, so as to greatly increase the static pressure of the fan. In addition, it can also provide low noise, high air volume and high air pressure performance, thereby achieving a better heat dissipation effect. the

Description of drawings

FIG. 1A is a bottom view of a conventional cooling fan. the

FIG. 1B is an internal sectional view of the conventional cooling fan shown in FIG. 1A . the

FIG. 2A is a perspective view of a preferred embodiment of the cooling fan of the present invention. the

FIG. 2B is a cross-sectional view of the cooling fan shown in FIG. 2A . the

FIG. 3A is a perspective view of a fan frame structure in the cooling fan shown in FIG. 2A . the

Fig. 3B and Fig. 3C are the upper view and the lower view of the fan frame structure shown in Fig. 3A. the

Fig. 4 is a schematic diagram of the arrangement of the moving blades and the stationary blades in the cooling fan of the present invention. the

Fig. 5 is a perspective view of another preferred embodiment of the fan frame structure of the present invention. the

Explanation of reference signs

11: fan frame 12: impeller

13: Rib 25: Hub

26: Blade 21: Frame

22: Base 231: Diverter

24: Static leaf 232: Another deflector

251: Bevel

Detailed ways

Please refer to FIG. 2A and FIG. 2B , which show a first preferred embodiment of the cooling fan of the present invention. The cooling fan includes a fan wheel and a fan frame structure. The fan wheel includes a hub 25 and a plurality of blades 26 arranged around the hub. As for the structure of the fan frame, please refer to Fig. 3A to Fig. 3C, which includes an outer frame 21, a base 22, a guide part (or guide angle) 231 and a plurality of vanes 24, wherein the plurality of The vane 24 can be connected between the base 22 and the inner guide part 23 of the outer frame. In other words, the plurality of vanes are arranged radially and connected between the base 22 and the inner surface of the outer frame. The space is used to guide the airflow flowing through the blades and increase the static pressure of the airflow blown out by the cooling fan. In addition, the plurality of vanes can also be designed such that one end is only connected to the base, while the other free end extends toward the flow guiding portion 23 , and vice versa. the

As shown in FIG. 2B , in addition to providing an air guide portion 231 on the air outlet side of the fan frame structure, another air guide portion 232 may also be formed on the air inlet side of the fan frame structure. The two guide parts respectively located on the air inlet side and the air outlet side of the fan frame structure can be symmetrically arranged as mirror images. In addition, along the direction from the air outlet side to the air inlet side (arrow direction D), the outer diameter of the hub gradually decreases from one end to the other end of the hub, forming a slope 251 . the

Now, please refer to Fig. 4, it is in order to explain the design principle of the present invention, wherein Va represents the speed of axial direction, Vt represents the speed of tangential direction, P0 is the pressure before the rotating blade of air-flow through fan wheel, and P1 is that air-flow passes through The pressure behind the rotating blades of the fan wheel, P2 is the pressure after the airflow passes through the stator blades. According to Bernulli Equation:

P2+0.5×ρ×Va ² ＝P1+0.5×ρ(Va ² +Vt ² )

Therefore, the change in pressure ΔP=P2-P1=0.5×ρ×Vt2

However, the present invention uses the design of the stationary vane to make Vt close to 0. In addition, as shown in Figure 2B, the static pressure can be increased by using the change relationship of the areas A1 and A2 in the figure:

ΔP＝0.5×ρ×[(Q/A1) ² -(Q/A2) ² ]

Where ρ is the air density and Q is the air flow. the

By the above method, that is, the design and area of the vanes on the fan frame are changed, and the axial and radial speeds are reduced at the same time, so as to greatly increase the static pressure of the fan. Of course, in order to achieve this purpose, the height of the vane and the depth of the guide part in the present invention need to be somewhat limited. Preferably, the depth h1 of the guide part is at least one-half of the height h2 of the vane. Alternatively, the height h2 of the vane is at least greater than one-fifth of the thickness H of the outer frame. In addition, the change relationship from the area A0 to the area A1 can achieve the purpose of reducing the disturbance. the

The outer frame, the base, the deflector and the plurality of stationary vanes can be made by one-piece injection molding, and the outer frame used can be a square, rectangular or circular frame, such as the circle shown in Figure 5 Shaped frame, the position of the guide part can expand radially outward. As for its material, it can be plastic or metal, such as aluminum frame. the

To sum up the above, the heat dissipation device and its fan frame structure provided by the present invention use the vanes on the fan frame and the change in area, while reducing the axial and radial speeds, so as to greatly increase the static pressure of the fan. In addition, it can also provide low noise, high air volume and high air pressure performance, thereby achieving a better heat dissipation effect. the

Therefore, the present invention can be modified in various ways by those who are familiar with the art, but they are all within the desired protection of the scope of the patent application. the

Claims (19)

1. fan frame structure that is used for heat abstractor, it comprises:

One housing has a pedestal, the common definition of an impeller wheel hub of this pedestal and this heat abstractor one accommodation space;

One diversion division is formed at the air side of this fan frame structure at least, and this diversion division radially outward expands in this air side to be stretched, and changing the area change in the fan frame structure, and changes the axial velocity of air-flow; And

A plurality of stator blades are disposed between this diversion division and this pedestal, in order to steering current,

Wherein this housing, this pedestal, this diversion division and this a plurality of stator blades are the one ejection formation,

The external diameter of this wheel hub is phased down by direction to the other end of an end past inlet air side along the air side of this wheel hub.

2. fan frame structure as claimed in claim 1, wherein this diversion division also is formed at the inlet air side of this fan frame structure.

3. fan frame structure as claimed in claim 1, wherein the height of this stator blade is greater than 1/5th of the thickness of this housing.

4. fan frame structure as claimed in claim 1, wherein the degree of depth of diversion division is greater than 1/2nd of this stator blade height.

5. fan frame structure as claimed in claim 1, wherein this housing is a square, rectangle or circular frame.

6. fan frame structure as claimed in claim 1, wherein this housing is a metal frame or plastic cement frame.

7. fan frame structure as claimed in claim 1, wherein a wherein end of these a plurality of stator blades is connected in this pedestal, and its another free end extends towards this diversion division place.

8. fan frame structure as claimed in claim 1, wherein a wherein end of these a plurality of stator blades is connected in this diversion division, and its another free end is towards this base extension.

9. fan frame structure as claimed in claim 1, wherein these a plurality of stator blades are arranged radially and are connected between the inner surface of this pedestal and this housing.

10. fan frame structure as claimed in claim 1, wherein this diversion division is formed at the inlet air side and the air side of this housing respectively, and becomes the mirror image balanced configuration.

11. a heat abstractor comprises:

One impeller, it comprises a wheel hub and a plurality of this wheel hub blade on every side that is located on; And

One fan frame structure, in order to ccontaining this impeller, it comprises:

One housing has a pedestal, the common definition of this pedestal and this wheel hub one accommodation space;

One diversion division is formed at the air side of this housing at least, and this diversion division radially outward expands in this air side to be stretched, and changing the area change in the fan frame structure, and changes the axial velocity of air-flow; And

A plurality of stator blades are disposed between this diversion division and this pedestal, in order to directed flow through the air-flow of blade and promote the static pressure of air-flow that this heat abstractor blows out,

Wherein this housing, this pedestal, this diversion division and this a plurality of stator blades are the one ejection formation,

The external diameter of this wheel hub is phased down by direction to the other end of an end past inlet air side along the air side of this wheel hub.

12. heat abstractor as claimed in claim 11, wherein the height of this stator blade is greater than 1/5th of the thickness of this housing.

13. heat abstractor as claimed in claim 11, wherein the degree of depth of this diversion division is greater than 1/2nd of this stator blade height

14. heat abstractor as claimed in claim 11, wherein this housing is a square, rectangle or circular frame.

15. heat abstractor as claimed in claim 11, wherein this housing is a metal frame or plastic cement frame.

16. heat abstractor as claimed in claim 11, wherein a wherein end of these a plurality of stator blades is connected in this pedestal, and its another free end extends towards this diversion division place.

17. heat abstractor as claimed in claim 11, wherein a wherein end of these a plurality of stator blades is connected in this diversion division, and its another free end is towards this base extension.

18. heat abstractor as claimed in claim 11, wherein these a plurality of stator blades are arranged radially and are connected between the inner surface of this pedestal and this housing.

19. heat abstractor as claimed in claim 11, wherein this diversion division is formed at the inlet air side and the air side of this housing respectively, and becomes the mirror image balanced configuration.

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