HEAT DISSIPATION MODULE WITH WIND STOP FUNCTION

Abstract

A heat dissipation module includes a centrifugal fan and a heat dissipation fin array. The centrifugal fan includes at least one axial air inlet and a radial air outlet, wherein the radial air outlet is defined between a first sidewall and an opposite second sidewall with a tongue potion. The heat dissipation fin array is located at the radial air outlet of the centrifugal fan. The heat dissipation fin array and the radial air outlet substantially share an equal length L. The heat dissipation fin array has a middle wind stop section which is closer to the second sidewall than the first sidewall. The wind stop section has a length ranging from about 0.1 L to about 0.42 L.

Description

BACKGROUND

1. Field of Invention

The present invention relates to a heat dissipation module. More particularly, the present invention relates to a heat dissipation module equipped with a centrifugal fan.

2. Description of Related Art

A heat dissipation module equipped with a centrifugal fan is used in most notebook computers as their system coolers. The heat dissipation module includes a centrifugal fan, a heat pipe and a heat dissipation fin array. An first end of the heat pipe is used to connect with a heat source, e.g., a CPU, while a second opposite end of the heat pipe is used to connect with the heat dissipation fin array, thereby transferring heat from the heat source to the heat dissipation fin array. The heat dissipation fin array is fastened to an air outlet of the centrifugal fan. When an impeller of the centrifugal fan rotates, airflows carry the heat on the heat dissipation fin array out of the notebook computer.

However, the notebook computers are designed to be thin and compact, the dissipation modules inside them are also designed to be thinner. When the notebook computers are designed to be less than 20 mm in thickness, a gap between the dissipation module and a top cover or between the dissipation module and a bottom cover becomes narrower. Thus, the centrifugal fan may draw not enough input air from its axial air inlet and perform not very well in the heat dissipation efficiency. For the forgoing reasons, there is a need for dealing the heat dissipation efficiency issue due to the thinner notebook computer design.

SUMMARY

It is therefore an objective of the present invention to provide a heat dissipation module with a wind stop function.

In accordance with the foregoing and other objectives of the present invention, a heat dissipation module includes a centrifugal fan and a heat dissipation fin array. The centrifugal fan includes at least one axial air inlet and a radial air outlet, wherein the radial air outlet is defined between a first sidewall and an opposite second sidewall with a tongue potion. The heat dissipation fin array is located at the radial air outlet of the centrifugal fan. The heat dissipation fin array and the radial air outlet substantially share an equal length L. The heat dissipation fin array has a middle wind stop section which is closer to the second sidewall than the first sidewall. The wind stop section has a length ranging from about 0.1 L to about 0.42 L.

According to another embodiment disclosed herein, the length of the wind stop section is about 0.26 L.

According to another embodiment disclosed herein, the wind stop section begins 0.48 L from the first sidewall and ends 0.74 L from the first sidewall.

According to another embodiment disclosed herein, a heat pipe which has a first end connected with the heat dissipation fin array and a second opposite end connected with a heat source.

According to another embodiment disclosed herein, the wind stop section is a wind-stop sponge contained within the heat dissipation fin array.

According to another embodiment disclosed herein, the wind stop section is a wind-stop tape disposed at a side of the heat dissipation fin array which faces the radial air outlet.

According to another embodiment disclosed herein, the wind stop section is a wind-stop tape disposed at a side of the heat dissipation fin array which faces away from the radial air outlet.

According to another embodiment disclosed herein, the length of the wind stop section is about 0.1 L.

According to another embodiment disclosed herein, the wind stop section begins 0.56 L from the first sidewall and ends 0.66 L from the first sidewall.

According to another embodiment disclosed herein, the length of the wind stop section is about 0.42 L.

According to another embodiment disclosed herein, the wind stop section begins 0.4 L from the first sidewall and ends 0.82 L from the first sidewall.

According to another embodiment disclosed herein, the centrifugal fan comprises an impeller with multiple blades, and each blade has a free end curved forward in a rotation direction of the impeller.

Thus, the heat dissipation module disclosed herein employs its wind-stop section on the heat dissipation fin array to deal with the reverse flow issue at the radial air outlet of the centrifugal fan, thereby resolving the hot spot issue on the heat dissipation module as well as the temperature over-spec. on the bottom cover of the notebook computer.

It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,

FIG. 1 illustrates a perspective view of a heat dissipation module according to a first embodiment of this invention;

FIG. 2 illustrates a top view of the heat dissipation module in FIG. 1 with a wind stop section added and a top cover of the centrifugal fan removed;

FIG. 3 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a second embodiment of this invention;

FIG. 4 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a third embodiment of this invention;

FIG. 5 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a fourth embodiment of this invention; and

FIG. 6 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a fifth embodiment of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.

FIG. 1 illustrates a perspective view of a heat dissipation module according to a first embodiment of this invention. The heat dissipation module 100 illustrated in FIG. 1 is used in most notebook computers as their system cooler. The heat dissipation module 100 includes a centrifugal fan 102, a heat pipe 110 and a heat dissipation fin array 112. The heat dissipation fin array 112 includes multiple dissipation fins which are arranged in parallel with an airflow direction of a radial air outlet 102a. A first end 110a of the heat pipe 110 is used to connect with a heat source, e.g., a CPU, (not illustrated in the drawings) while a second opposite end 110b of the heat pipe 110 is used to connect with the heat dissipation fin array 112, thereby transferring heat from the first end 110a to the second end 110b and the heat dissipation fin array 112. The heat dissipation fin array 112 is fastened to a radial air outlet 102a of the centrifugal fan to 102. When an impeller 108 of the centrifugal fan 102 rotates, airflows are drawn into the centrifugal fan 102 from an axial air inlet 102b and output from the radial air outlet 102a. Therefore, the heat upon the heat dissipation fin array 112 is carried out of the notebook computer by the airflows.

When a thickness of a notebook computer is less than 20 mm, i.e. a thickness of a present ultrabook computer, a gap between the centrifugal fan 102 and a top cover of a notebook computer or between the centrifugal fan 102 and a bottom cover of the notebook computer becomes narrower. The centrifugal fan 102 is equipped an impeller 108 with multiple blades 108a, and each blade 108a has a free end 108b curved forward in a rotation direction 120 of the impeller 108 (also referring to FIG. 2). When the notebook computer operates with a high load, e.g., playing a 3-D game or a 100% run CPU, a hot spot 113 is detected on the heat dissipation fin array 112. This hot spot 113 results in a temperature over-spec. by about 10 degrees on the bottom cover of the notebook computer.

An extensive search has been conducted and the problem source has been found to be a reverse flow 140 at the radial air outlet 102a of the centrifugal fan 102. When the gap between the centrifugal fan 102 and a top cover of the notebook computer or between the centrifugal fan 102 and a bottom cover of the notebook computer becomes too narrow, the centrifugal fan 102 draws less airflows from its (upper or lower) axial air inlet 102b, the reverse flow 140 occurs at the radial air outlet 102a of the centrifugal fan 102. Several solutions below are developed to deal with the reverse flow 140 at the radial air outlet 102a.

FIG. 2 illustrates a top view of the heat dissipation module in FIG. 1 with a wind stop section added and a top cover of the centrifugal fan removed. The centrifugal fan 102 is equipped an impeller 108 with multiple blades 108a, and each blade 108a has a free end 108b curved forward in a rotation direction 120 of the impeller 108. In order to prevent the reverse flow issue at the radial air outlet 102a, which is defined between a first sidewall 102c and an opposite second sidewall 102b with a tongue potion 102d, a wind stop section 112a is designed within the heat dissipation fin array 112. In order to specifically define the wind stop section 112a, the length L of the radial air outlet 102a is used. In this embodiment, the heat dissipation fin array 112 and the radial air outlet 102a substantially share the equal length L. The wind stop section 112a is middle within the heat dissipation fin array 112 and is closer to the second sidewall 102b than the first sidewall 102c. In this embodiment, the wind stop section 112a is a wind-stop sponge or other wind-stop materials contained within the heat dissipation fin array 112. The wind stop section 112a is about 0.26 L in length, which begins 0.48 L from the first sidewall 102c and ends 0.74 L from the first sidewall 102c.

FIG. 3 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a second embodiment of this invention. FIG. 4 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a third embodiment of this invention. More searches have been conducted on the reverse flow issue for other types of centrifugal fans. The wind stop section varies within a range. In FIG. 3, a narrower wind stop section 112a′ is a wind-stop sponge or other wind-stop materials contained within the heat dissipation fin array 112. The wind stop section 112a′ is about 0.1 L in length, which begins 0.56 L from the first sidewall 102c and ends 0.66 L from the first sidewall 102c. In FIG. 4, a wider wind stop section 112a″ is a wind-stop sponge or other wind-stop materials contained within the heat dissipation fin array 112. The wind stop section 112a″ is about 0.42 L in length, which begins 0.4 L from the first sidewall 102c and ends 0.82 L from the first sidewall 102c. In sum, the wind stop section may have a length ranging from about 0.1 L to about 0.42 L.

FIG. 5 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a fourth embodiment of this invention. FIG. 6 illustrates a top view of a heat dissipation module with a top cover of the centrifugal fan removed according to a fifth embodiment of this invention. In the first, second and third embodiments, the wind-stop section is contained within the heat dissipation fin array 112. In the fourth embodiment of FIG. 5, the wind stop section 112b is a wind-stop tape attached to a side of the heat dissipation fin array 112 which faces the radial air outlet 102a of the centrifugal fan 102. In the fifth embodiment of FIG. 6, the wind stop section 112c is a wind-stop tape attached to a side of the heat dissipation fin array which faces away from the radial air outlet 102a of the centrifugal fan 102.

With the wind stop section of the heat dissipation fin array, the reverse flow issue can be resolved so as to deal with the hot spot issue on the heat dissipation module as well as the temperature over-spec. on the bottom cover of the notebook computer.

According to the above-discussed embodiments, the heat dissipation module disclosed herein employs its wind-stop section on the heat dissipation fin array to deal with the reverse flow issue at the radial air outlet of the centrifugal fan, thereby resolving the hot spot issue on the heat dissipation module as well as the temperature over-spec. on the bottom cover of the notebook computer.

It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.

Claims

1. A heat dissipation module comprising:

a centrifugal fan comprising at least one axial air inlet and a radial air outlet, wherein the radial air outlet is defined between a first sidewall and an opposite second sidewall with a tongue potion; and

a heat dissipation fin array disposed at the radial air outlet of the centrifugal fan, wherein the heat dissipation fin array and the radial air outlet substantially share an equal length L, the heat dissipation fin array has a middle wind stop section which is closer to the second sidewall than the first sidewall, the wind stop section has a length ranging from about 0.1 L to about 0.42 L.

2. The heat dissipation module of claim 1, wherein the length of the wind stop section is about 0.26 L.

3. The heat dissipation module of claim 2, wherein the wind stop section begins 0.48 L from the first sidewall and ends 0.74 L from the first sidewall.

4. The heat dissipation module of claim 1 further comprising a heat pipe which has a first end connected with the heat dissipation fin array and a second opposite end connected with a heat source.

5. The heat dissipation module of claim 1, wherein the wind stop section is a wind-stop sponge contained within the heat dissipation fin array.

6. The heat dissipation module of claim 1, wherein the wind stop section is a wind-stop tape disposed at a side of the heat dissipation fin array which faces the radial air outlet.

7. The heat dissipation module of claim 1, wherein the wind stop section is a wind-stop tape disposed at a side of the heat dissipation fin array which faces away from the radial air outlet.

8. The heat dissipation module of claim 1, wherein the length of the wind stop section is about 0.1 L.

9. The heat dissipation module of claim 8, wherein the wind stop section begins 0.56 L from the first sidewall and ends 0.66 L from the first sidewall.

10. The heat dissipation module of claim 1, wherein the length of the wind stop section is about 0.42 L.

11. The heat dissipation module of claim 10, wherein the wind stop section begins 0.4 L from the first sidewall and ends 0.82 L from the first sidewall.

12. The heat dissipation module of claim 1, wherein the centrifugal fan comprises an impeller with multiple blades, and each blade has a free end curved forward in a rotation direction of the impeller.