Patent Application
20070251675
The present invention relates generally to a thermal module, and more particularly to a thermal module for dissipating heat generated by electronic components.
Referring to
In operation of the thermal module 30, the base plate 31 absorbs heat from the heat generating component, and transfers the heat to the evaporator section 341 of the heat pipe 34. The evaporator section 341 of the heat pipe 34 transmits the heat to the condenser section 342 of the heat pipe 34 via the evaporation and condensation of the working medium in the heat pipe 34. Then, the heat is transferred to the fin assembly 32 and taken away by the airflow passing through air channels formed between two adjacent fins. Thus, the heat dissipation of the heat-generating component is accomplished.
During the operation of the thermal module 30, the size of contact area between the condenser section 342 of the heat pipe 34 and the fin assembly 32 directly affects the heat dissipation efficiency of the thermal module 30. An effective way to improve the heat dissipation efficiency of the thermal module 30 is to increase the contacting area between the condenser section 342 of the heat pipe 34 and the fin assembly 32. Generally, the heat pipe 34 is flattened to satisfy such requirement. Moreover, the flattened heat pipe 34 can reduce a height of the thermal module 30 whereby the thermal module 30 can be more suitably used in a laptop computer, which is required to have a profile as small as possible. Since the condenser section 342 of the heat pipe 34 is linear shaped, such way of increasing the contact area does not increase the heat dissipation efficiency of the thermal module 30 enough the meet the more and more demanding requirement of heat dissipation for up-to-date laptop computers. Thus, a thermal module which can further increase the contact area between the condenser section 342 of the heat pipe 34 and the fin assembly 32 is needed.
The present invention relates to a thermal module for dissipating heat from a heat-generating electronic component. According to a preferred embodiment of the present invention, the thermal module includes a fin assembly, and a heat pipe including an evaporator section and a curve shaped condenser section. The evaporator section of the heat pipe thermally contacts with the heat-generating electronic component, and the condenser section of the heat pipe is disposed on the fin assembly along a longitudinal direction of the fin assembly. The curve shaped condenser section increases thermal contact area between the heat pipe and the fin assembly, thereby increasing heat dissipation efficiency of the thermal module.
Other advantages and novel features of the present invention will become more apparent from the following detailed description of preferred embodiment when taken in conjunction with the accompanying drawings, in which:
Referring to
The base plate 11 is made of materials having good heat conductivity, such as copper or aluminum, and defines a groove 111 for receiving the heat pipe 14 therein. The base plate 11 has a bottom surface contacting with a heat generating electronic component (not shown), and a top surface contacting with the heat pipe 14.
The heat-dissipating fan 13 is a centrifugal blower connected with an end of the base plate 11 for providing a high-pressure airflow. The heat-dissipating fan 13 includes a casing 131, a stator (not shown) mounted in the casing 131, and a rotor 132 rotatably disposed around the stator. An air inlet 133 is defined in a top wall of the casing 131, while an air outlet 134 is defined in a sidewall of the casing 131 perpendicular to the air inlet 133. A supporting plate 135 extends from a bottom wall of the casing 131 at the air outlet 134 of the heat-dissipating fan 13 to support the fin assembly 12. When the heat-dissipating fan 13 is activated, the rotor 132 rotates in a counterclockwise direction when viewed from the top wall of the heat-dissipating fan 13 of
The fin assembly 12 is mounted to the supporting plate 135 of the heat dissipating fan 13. The fin assembly 12 is stacked by a plurality of fins 121 parallel to each other, and includes an end 123 adjacent to the left side 136 of the air outlet 134 of the heat-dissipating fan 13. Each of the fins 121 perpendicularly extends a flange 124 at a top and a bottom portion thereof. The fins 121 are arranged along a longitudinal direction of the supporting plate 135 of the heat-dissipating fan 13, with the flanges 124 of a left fin 121 abutting against a body of a right fin 121. A supporting surface 122 is formed on a top surface of the fin assembly 12 by the flanges 124 of the fins 121.
The heat pipe 14 is mounted on the fin assembly 12 with a bottom surface thereof intimately contacting with the supporting surface 122 of the fin assembly 12. The heat pipe 14 includes an evaporator section 141 received in the groove 111 of the base plate 11, and a curve shaped condenser section 142 contacting with the fin assembly 12. The configuration of the condenser section 142 according to this preferred embodiment is “S” shaped with two arcs. Alternatively, the condenser section 142 can be serpentine with more than two arcs. The condenser section 142 of the heat pipe 14 includes an arc shaped bending portion 143 formed thereon. The bending portion 143 is disposed adjacent to the left side 136 of the air outlet 134 of the heat-dissipating fan 13, aligning with the end 123 of the fin assembly 12. In the present invention, interface materials such as thermal greases (not shown) are spread on both the top surface of the base plate 11 and the supporting surface 122 of the fin assembly 12, so as to maintain good thermal contact between the evaporator section 141 and the condenser section 142 of the heat pipe 14 and their attached base plate 11 and the fin assembly 12.
In operation of the thermal module 10, the base plate 11 absorbs heat from the heat-generating component, and transfers the heat to the evaporator section 141 of the heat pipe 14. The evaporator section 141 of the heat pipe 14 transmits the heat to the condenser section 142 of the heat pipe 14 via the evaporation and condensation of the working medium in the heat pipe 14. Then, the heat is transferred to the fin assembly 12 and taken away by the airflow passing through air channels formed between two adjacent fins 121. Thus, the heat generated by the heat-generating component is dissipated and a safe temperature maintained.
In the present invention, the condenser section 142 of the heat pipe 14 is bent so as to be “S” shaped, which increases a length of the condenser section 142 of the heat pipe 14 disposed on the fin assembly 12. This increases the thermal contact area between the heat pipe 14 and the fin assembly 12. Thus, the heat pipe 14 will transfer more heat directly to the fin assembly 12, thereby increasing heat dissipation efficiency of the thermal module 10. In the thermal module 10, the configuration and size of condenser section 142 of the heat pipe 14 is designed according to the size of the supporting surface 122 of the fin assembly 12, giving the largest possible contact area between the condenser section 142 of the heat pipe 14 and the fin assembly 12.
Compared to the heat pipe 34 of the related art, the “S” shaped condenser section 142 of the heat pipe 14 has greater contact area between the bending portion 143 of the heat pipe 14 and the end 123 of the fin assembly 12. This makes adequate use of the kinetic energy of the airflow adjacent to the left side 136 of the air outlet 134, further increasing the heat dissipation efficiency of the thermal module 10. The condenser section 142 has the bending portion 143 (i.e., first arc) extended to be proximate to a front edge of the fin assembly 12 distant from the fan 13, and the other bending portion (i.e., a second arc, not labeled) extended to be proximate to a rear edge of the fin assembly 12 close to the fan 13. Thus, the condenser section 142 can have an even contact with the fin assembly 12 to effectively dissipate the heat to the fin assembly 12.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
