Abstract:
A heat pipe cooling system comprising an evaporator, a pipeline, a working fluid and a thermal connector is provided. The evaporator is connected to a heat-generating element, and the pipeline is connected to the evaporator. The working fluid is injected into a closed loop formed by the evaporator and the pipeline. The thermal connector comprises a first thermal conductive block and a second thermal conductive block. The first thermal conductive block has many first fitting parts and a contact surface. The contact surface is suitable for attaching to one of the surfaces of an object. The second thermal conductive block has many second fitting parts. The second fitting parts are suitable for meshing with the first fitting parts to form a piping channel inside the thermal connector. The piping channel is suitable for enclosing a section of the pipeline or directly serving as a part of the pipeline.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims the priority benefit of People&#39;s Republic of China application serial no. 200510007414.8, filed on Feb. 18, 2005. All disclosure of the People&#39;s Republic of China application is incorporated herein by reference.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a cooling system and its cooling elements. More particularly, the present invention relates to a heat pipe cooling system and a thermal connector thereof.  
         [0004]     2. Description of the Related Art  
         [0005]     To remove the heat produced by a heat-generating device in operation and prevent over-heating due to the rapid accumulation of heat around the heat-generating device, a heat sink is often attached to the surface of the heat-generating device. Furthermore, a fan is also used to force a stream of air over the heat sink and produce a convective current that carries the heat away from the heat sink and prevents the over-heating of the device.  
         [0006]     However, as the quantity of heat generated by the device is increased, the conventional heat dissipation method will become a bottleneck. To match the increase in heat production by a heat-generating device so that the device can operate within a normal operating temperature range, the conventional technique demands an increase in the total surface area of cooling fins on the heat sink or the rotational speed of the fan. Yet, if the heat-generating device is disposed inside the limited space of an enclosed housing, then increasing the surface area of fins will increase the spatial occupation of the cooling fins. On the other hand, if the rotational speed of the fan is increased to provide a more forceful convection, more vibration and noise will be produced in addition to an increase in energy consumption.  
         [0007]     In recent years, a thermal device that conducts heat away through the phase change in a working fluid has been developed. These phase-change thermal devices include two major types: the loop heat pipe and the capillary pump loop, for example. To carry heat away from a heat-generating device, the working fluid in an evaporator absorbs the heat and changes into a gaseous phase. A capillary structure separates the liquid working fluid and the gaseous working fluid. A sufficiently powerful pressure differential is established between the inside and outside of the capillary structure. Then, the pressure differential drives the working fluid to recycle in the loop system. In the recycling process, the heat absorbed by the gaseous working fluid is released inside a condenser so that the working fluid returns to a liquid phase. Because the capillary structure inside the thermal device can produce a sufficiently large capillary force to resist the friction of the working fluid flowing inside the thermal device, the phase-change thermal device is able to carry heat away from a heat source over a long distance to a condenser.  
         [0008]     For example, when a central processing unit (CPU) is disposed inside a limited space within a computer casing, the phase-change thermal device can carry the heat produced by the CPU through a pipeline to a suitable location where heat can be dissipated. Thus, the heat-dissipating device is no longer constrained by the limited space inside the computer casing. Other advantage of the heat pipe cooling system includes a sturdy package, a high thermal conductive capacity, a flexible pipeline routing, a power source free operation and an operation unaffected by gravity.  
       SUMMARY OF THE INVENTION  
       [0009]     Accordingly, at least one objective of the present invention is to provide a thermal connector for linking the pipeline of a heat pipe cooling system to an object and using the object as a condenser for the heat pipe cooling system.  
         [0010]     At least a second objective of the present invention is to provide a heat pipe cooling system for transferring the heat from a heat-generating device to an object and using the object as a condenser of the heat pipe cooling system to remove the heat.  
         [0011]     To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a thermal connector. The thermal connector comprises a first thermal conductive block and a second thermal conductive block. The first thermal conductive block has a plurality of first fitting parts and a contact surface. The contact surface is attached to one of the surfaces of an object. The second thermal conductive block has a plurality of second fitting parts suitable for meshing with the first fitting parts. When the second fitting parts mesh with the first fitting parts, the first thermal conductive block and the second thermal conductive block together form a piping channel inside the thermal connector suitable for enclosing a section of the pipeline or directly serving as a part of the pipeline.  
         [0012]     According to the preferred embodiment of the present invention, each first fitting part of the thermal connector is a spine and a corresponding second fitting part of the thermal connector is a groove.  
         [0013]     According to the preferred embodiment of the present invention, each first fitting part of the thermal connector is a groove and a corresponding second fitting part of the thermal connector is a spine.  
         [0014]     According to the preferred embodiment of the present invention, the piping channel meanders inside the interior of the thermal connector after assembling the first thermal conductive block and the second thermal conductive block together.  
         [0015]     According to the preferred embodiment of the present invention, the seams on the surface after assembling the first thermal conductive block and the second thermal conductive block together are sealed using a soldering material.  
         [0016]     According to the preferred embodiment of the present invention, each first fitting part is tightly fitted into a corresponding second fitting part.  
         [0017]     According to the preferred embodiment of the present invention, the piping channel tightly encloses the connecting pipeline when the piping channel accommodates a section of the connecting pipeline.  
         [0018]     According to the preferred embodiment of the present invention, the thermal connector after assembling the first thermal conductive block and the second thermal conductive block together can be detachably connected to the object such that the contact surface is attached to the surface of the object.  
         [0019]     According to the preferred embodiment of the present invention, the thermal connector after assembling the first thermal conductive block and the second thermal conductive block together can be mounted onto the object using a set of screws. The screws tighten the two together so that the contact surface of the thermal connector is attached to the surface of the object.  
         [0020]     According to the preferred embodiment of the present invention, the thermal connector after assembling the first thermal conductive block and the second thermal conductive block together is attached to the object through magnetic force of attraction so that the contact surface is attached to the surface of the object.  
         [0021]     The present invention also provides a heat pipe cooling system comprising an evaporator, a connecting pipeline, a working fluid and the aforementioned thermal connector. The evaporator is connected to the heat-generating device. The connecting pipeline is linked to the evaporator. The working fluid is injected into a closed loop formed by the evaporator and the pipeline.  
         [0022]     According to the preferred embodiment of the present invention, the heat pipe cooling system further comprises a cooling module connected to the evaporator, and the cooling module comprises a plurality of cooling fins coupling to thermal connector and a fan mounted on the fins.  
         [0023]     In the present invention, the heat from a heat source is transferred to an object attached to the thermal conductive block through the connecting pipeline of a heat pipe cooling system. Then, the heat is dissipated from the surface of the object in a natural or forced convection. Thus, the heat produced by a heat-generating device can be removed through the heat pipe cooling system of the present invention with a very low energy budget.  
         [0024]     It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]     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.  
         [0026]      FIG. 1  is a schematic cross-sectional view of a heat pipe cooling system according to one embodiment of the present invention.  
         [0027]      FIG. 2  is a perspective view of the thermal connector in  FIG. 1 .  
         [0028]      FIG. 3  is an explosion view of the components of the thermal connector in  FIG. 2 .  
         [0029]      FIG. 4  is a perspective view of the first thermal conductive block in  FIG. 3 .  
         [0030]      FIG. 5  is a perspective view of the second thermal conductive block in  FIG. 3 .  
         [0031]      FIG. 6  is a rough sketch showing the external appearance of the heat pipe cooling system in  FIG. 1 .  
         [0032]      FIG. 7  is a rough sketch showing the external appearance of the heat pipe cooling system according to another embodiment of the present invention.  
         [0033]      FIG. 8  is an explosion view of the components of the thermal connector according to another embodiment of the present invention.  
         [0034]      FIG. 9  is a perspective view of the second thermal conductive block in  FIG. 8 .  
         [0035]      FIG. 10  is a rough sketch showing the external appearance of a heat pipe cooling system according to another embodiment of the present invention that uses the thermal connector shown in  FIG. 8 .  
         [0036]      FIG. 11  is a perspective view of a light-emitting diode streetlight using the heat pipe cooling system shown in  FIG. 6 .  
         [0037]      FIG. 12  is a perspective view of a desktop computer using the heat pipe cooling system shown in  FIG. 6 .  
         [0038]      FIG. 13  is a perspective view of a desktop computer using the heat pipe cooling system shown in  FIG. 7 . 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0039]     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.  
         [0040]      FIG. 1  is a schematic cross-sectional view of a heat pipe cooling system according to one embodiment of the present invention. As shown in  FIG. 1 , the heat pipe cooling system  100  mainly comprises an evaporator  110 , a connecting pipeline  120 , a working fluid  130  and a thermal connector  140 . A heat-generating device  150  is attached to the evaporator  110  and the connecting pipeline  120  is linked to the evaporator  110 . The working fluid  130  is injected into the closed loop formed by the evaporator  110  and the connecting pipeline  120 . The evaporator  110  further comprises an evaporation wall  112 , a wick structure  114  and a vaporizing groove  116 . The wick structure  114  is disposed inside the evaporation wall  112  and the plurality of vaporizing grooves  116  is disposed between the evaporation wall  112  and the wick structure  114 .  
         [0041]     When a quantity of heat Q produced by the heat-generating device  150  is conducted to the evaporator  110 , the heat Q passes through the evaporation wall  112  into the wick structure  114 . The liquid phase working fluid  130  soaked up by the wick structure  114  absorbs the heat Q and vaporizes into a gaseous working fluid  130 . Then, the gaseous working fluid  130  flows along the vaporizing groove  116  and the connecting pipeline  120  to the thermal connector  140  where the heat Q is dissipated. As the gaseous working fluid  130  releases the heat Q in the thermal connector  140 , the gaseous working fluid  130  also condenses back to a liquid state and returns to the wick structure  114  inside the evaporator  110  along the connecting pipeline  120  to complete a cycle.  
         [0042]     Note that the main concept behind the present invention is that the thermal connector  140  is designed to attach to an object  160  that serves as a condenser of the heat pipe cooling system  100 . The heat transferred to the object  160  is then removed by natural or forced convection. The object  160  can be a metal casing or any material suitable for exchanging heat with the environment, for example. In the following, the structure of the thermal connector  140  and the applications of the heat pipe cooling system  100  are described in more detail.  
         [0043]      FIG. 2  is a perspective view of the thermal connector in  FIG. 1 .  FIG. 3  is an explosion view of the components of the thermal connector in  FIG. 2 .  FIG. 4  is a perspective view of the first thermal conductive block in  FIG. 3 .  FIG. 5  is a perspective view of the second thermal conductive block in  FIG. 3 . As shown in FIGS.  1  to  5 , the thermal connector  140  mainly comprises a first thermal conductive block  142  and a second thermal conductive block  144 . The first thermal conductive block  142  has a plurality of first fitting parts  146  and each first fitting part  146  is a spine (see  FIG. 4 ), for example. The second thermal conductive block  144  has a plurality of second fitting parts  148  with each second fitting part corresponding to a first fitting part  146 . Furthermore, the second fitting parts  148  are grooves (see  FIG. 5 ), for example. Obviously, in another embodiment, the first fitting parts  146  can be grooves and the second fitting parts  148  can be spines. When the first thermal conductive block  142  and the second thermal conductive block  144  are assembled together, a piping channel  149  is formed inside the thermal connector  140 . Hence, the working fluid  130  can flow in the piping channel  149 . In addition, the first thermal conductive block  142  and the second thermal conductive block  144  can be joined together by applying soldering material to seal the gaps between the two blocks so that the working fluid  130  is prevented from leaking out through the gaps between the two thermal conductive blocks  142  and  144 .  
         [0044]      FIG. 6  is a rough sketch showing the external appearance of the heat pipe cooling system in  FIG. 1 . As shown in  FIGS. 5 and 6 , when the thermal connector  140  and the connecting pipeline  120  are joined together, the piping channel  149  shown in  FIG. 5  can serve as a part of the connecting pipeline  120 . Hence, when the gaseous working fluid  130  moves into the thermal connector  140 , the heat within the gaseous working fluid  130  can be directly transferred to the object  160  via the thermal connector  140  (see  FIG. 1 ). It should be noted that the heat pipe cooling system  100  may use a suitable saddle  118  that matches the geometric shape of the heat-generating device (not shown) to transfer the heat Q uniformly to the evaporator  110 . In addition, the connecting pipeline  120  of the heat pipe cooling system  100  may be suitably bent according to the actual requirements so that the heat pipe cooling system  100  can have a more flexible outward appearance.  
         [0045]      FIG. 7  is a rough sketch showing the external appearance of the heat pipe cooling system according to another embodiment of the present invention. Heat pipe cooling system  100  may further comprises a cooling module  170 . The cooling module  170  comprises a plurality of cooling fins  172  and a fan  174  wherein the fan  174  is mounted on the cooling fins  172 . Therefore, the size of the thermal connector  140  and the air flow of the fan  174  can be flexibly adjusted such that the cooling performance of the heat pipe cooling system  100  can be optimized.  
         [0046]      FIG. 8  is an explosion view of the components of the thermal connector according to another embodiment of the present invention.  FIG. 9  is a perspective view of the second thermal conductive block in  FIG. 8 . As shown in  FIGS. 4, 8  and  9 , the first thermal conductive block  142 ′ can have a plurality of second fitting parts  146 ′ with a spine design, and the second thermal conductive block  144 ′ can have a plurality of second fitting parts  148 ′ with a groove design. Hence, straight piping channels  149 ′ are formed inside the thermal connector  140 ′ to accommodate a portion of the connecting pipeline  120  snugly.  
         [0047]      FIG. 10  is a rough sketch showing the external appearance of a heat pipe cooling system according to another embodiment of the present invention that uses the thermal connector shown in  FIG. 8 . As shown in  FIGS. 8 and 10 , when a portion of the connecting pipeline  120  is disposed inside the thermal connector  140 ′, the piping channel  149  encloses the portion of the connecting pipeline  120 . Thus, the heat Q within the gaseous working fluid  130  inside the connecting pipeline  120  can be transferred to the thermal connector  140  through the wall of the connecting pipeline  120  and then carried away to the object  160  (see  FIG. 1 ).  
         [0048]      FIG. 11  is a perspective view of a light-emitting diode streetlight using the heat pipe cooling system shown in  FIG. 6 . The light-emitting diode streetlight has great potential for public illumination. If the present invention is applied to this type of illumination equipment, the energy cost for installing a cooling system can be significantly reduced. As shown in  FIG. 11 , the evaporator  110  of the heat pipe cooling system  100  is mounted on the light-emitting diode light source  220  of the light-emitting diode streetlight  200  through a saddle  118 . The thermal connector  140  is detachably mounted on a metallic casing  210  using a set of screws or through magnetic force of attraction. Furthermore, a thermal conductive layer such as a layer of thermal conductive paste or a thermal conductive pad is set up between the thermal connector  140  and the metallic casing  210 . Consequently, the metallic casing  210  can be utilized as a condenser of the heat pipe cooling system  100  to remove the heat produced by the light-emitting diode light source  220  through natural convection with the surroundings. Since the heat pipe cooling system  100  is a passive thermal conductive device, there is no need to provide additional energy for transferring the heat from the light-emitting diode light source  220  to the surface of the metallic casing  210 . The heat can be effectively removed through the available surface area of the metallic casing  210  to the surroundings. Therefore, for the light-emitting diode streetlight  200  that needs to operate for a very long period of time, the heat pipe cooling system  100  of the present invention saves a lot of energy.  
         [0049]      FIG. 12  is a perspective view of a desktop computer using the heat pipe cooling system shown in  FIG. 6 . As shown in  FIG. 12 , the evaporator  110  of the heat pipe cooling system  100  is mounted on a heat-generating device  320  inside a desktop computer  300  through a saddle  118 . The heat-generating device  320  is a central processing unit (CPU), a graphic chip or other chip that generates large quantity of heat, for example. The thermal connector  140  is attached to the casing  310  of the desktop computer  300  using a detachable connection such as a set of screws or magnetic force of attraction. Since the thermal connector  140  is attached to a casing  310  fabricated from a metallic material such as aluminum alloy, the entire casing  310  will become the condenser of the heat pipe cooling system  100 . In other words, the heat produced by the heat-generating device can be removed from the desktop computer  300  through the casing  310 .  
         [0050]      FIG. 13  is a perspective view of a desktop computer using the heat pipe cooling system shown in  FIG. 7 . As shown in  FIG. 13 , the heat pipe cooling system  100  with the cooling module  170  shown in  FIG. 7  is installed in a desktop computer  300 . The heat pipe cooling system  100  has a plurality of thermal connector  140  disposed on a side plate  312  of a casing  310  of the desktop computer  300 , and utilizes the side plate  312  to be a condenser thereof.  
         [0051]     In summary, the thermal conductive block in the present invention can transfer the heat from a heat-generating device to an object attached to the thermal conductive block and using the object as a condenser of the heat pipe cooling system. Thus, the heat pipe cooling system of the present invention can remove heat from a heat-generating device with very little expenditure of energy cost.  
         [0052]     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.