Patent Publication Number: US-2023136588-A1

Title: Cooling liquid flow control device

Description:
CROSS - REFERENCE TO RELATED APPLICATION 
     This application claims priority to China Application Serial Number 202111300052.7, filed Nov. 4, 2021, which is herein incorporated by reference in its entirety. 
     BACKGROUND 
     Field of Invention 
     The present disclosure relates to a cooling liquid flow control device. 
     Description of Related Art 
     The water-cooling module of the conventional electronic components (for example, CPU) uses a thermally conductive substrate as the substrate, cooperating with the water inlet side and the water outlet side as the internal circulation loop for heat exchange to achieve the effect of heat dissipation of the electronic component, and utilizes the hole position corresponding to the electronic component platform to perform the fixation on the printed circuit board (PCB). 
     However, the conventional water-cooling module does not have the function of controlling the flow rate (for example, the flow rate of the cooling water). Since the water-cooling module cannot control the flow rate, the water-cooling module cannot optimize the heat dissipation of the electronic components in the idle or full load state, and thus cannot adjust the electrical load of the CDU to the system. 
     Therefore, how to propose a cooling liquid flow control device that can solve the aforementioned problems is one of the problems that the industry urgently wants to invest in research and development resources to solve. 
     SUMMARY 
     In view of this, one purpose of present disclosure is to provide a cooling liquid flow control device that can solve the aforementioned problems. 
     In order to achieve the above objective, according to one embodiment of the present disclosure, a cooling liquid flow control device includes a heat dissipation bottom plate, a fixing holder, a cooling module, and a temperature control element. The heat dissipation bottom plate includes a bottom surface configured to be in contact with the heating element on a substrate. The fixing holder is connected to the heat dissipation bottom plate and configured to be fixed with the substrate. The cooling module is connected to a top surface of the heat dissipation bottom plate to form a cavity. The cavity is configured to circulate a cooling liquid. The temperature control element is disposed in the cavity and is configured to deform based on a temperature of the cooling liquid in the cavity, thereby adjusting a flow rate of the cooling liquid in and out of the cavity. 
     In one or more embodiments of the present disclosure, the cooling liquid flow control device further includes a liquid inlet pipe and a liquid outlet pipe. The cavity further includes a first sub-cavity and a second sub-cavity. The first sub-cavity is configured to receive the cooling liquid from the liquid inlet pipe. The second sub-cavity surrounds the first sub-cavity and is configured to deliver the cooling liquid from the first sub-cavity to the liquid outlet pipe. 
     In one or more embodiments of the present disclosure, an opening is between the first sub-cavity and the second sub-cavity, and the opening allows the cooling liquid to circulate between the first sub-cavity and the second sub-cavity. 
     In one or more embodiments of the present disclosure, the cooling module further includes a top plate, an outer surrounding wall, and an inner surrounding wall. The top plate has a liquid inlet hole and a liquid outlet hole, in which the liquid inlet hole connects the liquid inlet pipe and the first sub-cavity, and the liquid outlet hole connects the liquid outlet pipe and the second sub-cavity. The outer surrounding wall extends vertically from an edge of the top plate and surrounds the edge of the top plate, in which the outer surrounding wall is connected to the heat dissipation bottom plate. The inner surrounding wall extends vertically from the top plate and surrounded by the outer surrounding wall, in which the inner surrounding wall is connected to the heat dissipation bottom plate. 
     In one or more embodiments of the present disclosure, the opening is located on the inner surrounding wall. 
     In one or more embodiments of the present disclosure, the temperature control element includes a first metal strip and a second metal strip. The first metal strip has a first coefficient of thermal expansion. The second metal strip is attached to the first metal strip and has a second coefficient of thermal expansion, in which the first coefficient of thermal expansion is less than the second coefficient of thermal expansion. 
     In one or more embodiments of the present disclosure, the temperature control element further includes a stop portion disposed on the second metal strip, and the stop portion is configured to clog and be separated from the liquid inlet hole. 
     In one or more embodiments of the present disclosure, an end of the temperature control element away from the stop portion is connected to an inner surface of the cavity. 
     In one or more embodiments of the present disclosure, the temperature control element is configured to bend toward a side of the second metal strip when the temperature of the cooling liquid is lower than a temperature threshold, so that the stop portion clogs the liquid inlet hole so as not to communicate the liquid inlet pipe and the first sub-cavity. 
     In one or more embodiments of the present disclosure, the temperature control element is configured to bend toward a side of the first metal strip when the temperature of the cooling liquid is higher than a temperature threshold, so that the stop portion is separated from the liquid inlet hole to communicate the liquid inlet pipe and the first sub-cavity. 
     In summary, in the cooling liquid flow control device of the present disclosure, since the temperature control element utilizes the characteristics of bimetallic strip generating deformation based on the temperature of the cooling liquid, the stop portion of the temperature control element can clog, partially clog, or be separated from the liquid inlet hole to achieve the purpose of controlling the flow rate of the cooling liquid. In the cooling liquid flow control device of the present disclosure, since the bimetallic strip is used as the material of the temperature control element, it can not only achieve the power saving effect of the cooling liquid flow control device, but also effectively reduce the installation space of the liquid cooling device. 
     The above-mentioned description is only used to explain the problem to be solved by the present disclosure, the technical means to solve the problem, and the effects produced, etc. The specific details of the present disclosure will be well discussed in the following embodiments and related drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order to make the above and other objectives, features, advantages and examples of the present disclosure more obvious, the description of the accompanying drawings is as follows: 
         FIG.  1    shows a schematic view of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  2    shows another schematic view of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  3 A  shows a partial schematic view of a cooling module of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  3 B  shows another partial schematic view of a cooling module of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  4    shows a schematic view of a temperature control element of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  5    shows a partial top view of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  6    shows a cross-sectional view of a cooling liquid flow control device, in accordance with an embodiment of present disclosure; 
         FIG.  7    shows a schematic view of a stop portion clogging a liquid inlet hole, in accordance with an embodiment of present disclosure; and 
         FIG.  8    shows a schematic view of a stop portion separated from a liquid inlet hole, in accordance with an embodiment of present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, a plurality of embodiments of the present disclosure will be disclosed in diagrams. For clarity of discussion, many details in practice will be described in the following description. However, it should be understood that these details in practice should not limit present disclosure. In other words, in some embodiments of present disclosure, these details in practice are unnecessary. In addition, for simplicity of the drawings, some conventionally used structures and elements will be shown in a simple schematic manner in the drawings. The same reference numbers are used in the drawings and the description to refer to the same or like parts. 
     Hereinafter, the structure and function of each component included in a cooling liquid flow control device of this embodiment and the connection relationship between the components will be described in detail. 
     Reference is made to  FIG.  1    and  FIG.  2   .  FIG.  1    and  FIG.  2    are schematic views of different visual angles of the cooling liquid flow control device  100  according to an embodiment of the present disclosure. In this embodiment, the cooling liquid flow control device  100  includes a heat dissipation bottom plate  110 , a fixing holder  120 , a cooling module  130 , and a temperature control element  140 . The heat dissipation bottom plate  110  has a top surface  110   a  and a bottom surface  110   b . The bottom surface  110   b  is configured to be in contact with a heating element (not shown; for example, CPU) on a substrate (not shown; for example, PCB). The fixing holder  120  is connected to the heat dissipation bottom plate  110  and configured to be fixed to the substrate. Specifically, as shown in  FIG.  1    and  FIG.  2   , the heat dissipation bottom plate  110  is connected to the fixing holder  120  by the fixing element S 1 , the heating element is in contact with the bottom surface  110   b  of the heat dissipation bottom plate  110 , and the heating element is located between the heat dissipation bottom plate  110  and the substrate. When the fixing holder  120  is fixed toward the substrate by the fixing element S 2 , the heat dissipation bottom plate  110  is pressed against the heating element. The cooling module  130  is connected to the top surface  110   a  of the heat dissipation bottom plate  110  to form a cavity C. The cooling module  130  also includes a liquid inlet pipe IT and a liquid outlet pipe OT. The cavity C is configured to circulate cooling liquid. The temperature control element  140  is disposed in the cavity C and is configured to cause a deformation based on the temperature of the cooling liquid in the cavity C, thereby adjusting the flow rate of the cooling liquid in and out of the cavity C. 
     Reference is made to  FIG.  1   ,  FIG.  3 A , and  FIG.  3 B . In this embodiment, the cooling module  130  includes a top plate  132 , an outer surrounding wall  134 , an inner surrounding wall  136 , and a pressing block  138 . The top plate  132  has a liquid inlet hole  132 A and a liquid outlet hole  132 B, the liquid inlet hole  132 A is connected to the liquid inlet pipe IT, and the liquid outlet hole  132 B is connected to the liquid outlet pipe OT. The outer surrounding wall  134  extends vertically from the edge of the top plate  132  and surrounds the edge of the top plate  132 . The inner surrounding wall  136  extends vertically from the top plate  132  and is surrounded by the outer surrounding wall  134 . The inner surrounding wall  136  also has an opening O. The pressing block  138  extends from the top plate  132  and is configured to press against the temperature control element  140  disposed in the cavity C. 
     Please refer to  FIG.  1    and  FIG.  4   , in this embodiment, the temperature control element  140  includes a first metal strip  142 , a second metal strip  144 , and a stop portion  146 . The first metal strip  142  and the second metal strip  144  are attached to each other. In  FIG.  4   , the size of the first metal strip  142  is substantially the same as the size of the second metal strip  144 . Since the first metal strip  142  is located on the back side of the temperature control element  140  in  FIG.  4   , the first metal strip  142  is not fully revealed. The first metal strip  142  has a first coefficient of thermal expansion, and the second metal strip  144  has a second coefficient of thermal expansion, wherein the first coefficient of thermal expansion is different from the second coefficient of thermal expansion. In some embodiments, the first coefficient of thermal expansion is less than the second coefficient of thermal expansion. The stop portion  146  is disposed on one end of the temperature control element  140 , and the stop portion  146  protrudes toward a side of the second metal strip  144 . The stop portion  146  is configured to clog and be separated from the liquid inlet hole  132 A. 
     Reference is made to  FIG.  1   ,  FIG.  5   , and  FIG.  6   . In this embodiment, the cavity C further includes a first sub-cavity C 1  and a second sub-cavity C 2 . Specifically, as shown in  FIG.  5    and  FIG.  6   , because when the cooling module  130  is connected to the heat dissipation bottom plate  110 , the outer surrounding wall  134  and the inner surrounding wall  136  are both connected to the heat dissipation bottom plate  110 , so that the top plate  132 , the inner surrounding wall  136 , and the heat dissipation bottom plate  110  jointly define the first sub-cavity C 1 , while the top plate  132 , the outer surrounding wall  134 , the inner surrounding wall  136 , and the heat dissipation bottom plate  110  jointly define the second sub-cavity C 2 . And, the second sub-cavity C 2  surrounds the first sub-cavity C 1 . The first sub-cavity C 1  is configured to receive the cooling liquid from the liquid inlet pipe IT, the opening O is configured to allow the cooling liquid to circulate between the first sub-cavity C 1  and the second sub-cavity C 2 . The second sub-cavity C 2  is configured to deliver the cooling liquid from the first sub-cavity C 1  to the liquid outlet pipe OT. Therefore, the liquid inlet hole  132 A is connected to the liquid inlet pipe IT and the first sub-cavity C 1 , and the liquid outlet hole  132 B is connected to the liquid outlet pipe OT and the second sub-cavity C 2 . 
     In some embodiments, as shown in  FIG.  4   , the stop portion  146  is substantially disposed on the second metal strip  144 . 
     In some embodiments, an end of the temperature control element  140  away from the stop portion  146  is substantially connected to the inner surface of the cavity C. For example, as shown in  FIG.  4    and  FIG.  6   , the heat dissipation bottom plate  110  may include a positioning column  112 , the temperature control element  140  may include a positioning hole  148 , and the positioning hole  148  is located at an end of the temperature control element  140  away from the stop portion  146 . In this way, the temperature control element  140  can be positioned on the positioning column  112  by the positioning hole  148 , and disposed in the cavity C by the pressing of the pressing block  138 . 
     Please continue to refer to  FIG.  5    and  FIG.  6   .  FIG.  5    and  FIG.  6    show how the cooling liquid circulates in the cooling liquid flow control device  100 , in which the black arrows represent the paths through where the cooling liquid circulates in the cooling liquid flow control device  100 . With the aforementioned structural configuration, when the cooling liquid flows into the first sub-cavity C 1  from the liquid inlet pipe IT, the cooling liquid enters the first sub-cavity C 1  through the liquid inlet hole  132 A. Then, the cooling liquid flows into the second sub-cavity C 2  located outside the first sub-cavity C 1  through the opening O. Then, when the cooling liquid flows into the liquid outlet pipe OT from the second sub-cavity C 2 , the cooling liquid system enters the liquid outlet pipe OT through the liquid outlet hole  132 B. 
     In some embodiments, the opening O and the liquid outlet hole  132 B are respectively close to the opposite sides of the cavity C, so that the cooling liquid can evenly flow through every part of the top plate  132 , so that the heat dissipation efficiency may be better. Compared with the case where the opening O and the liquid outlet hole  132 B are located on the same side of the cavity C, the cooling liquid flows directly into the liquid outlet pipe OT from the liquid outlet hole  132 B through the opening O, and the cooling liquid may not flow through certain parts of the top plate  132 , resulting in poor heat dissipation efficiency. 
     Next, the method of how the cooling liquid flow control device  100  controls the flow rate of the cooling liquid will be discussed. 
     Reference is made to  FIG.  7    and  FIG.  8   .  FIG.  7    and  FIG.  8    show how the temperature control element  140  operates to control the flow rate of the cooling liquid in the cooling liquid flow control device  100 . Since the temperature control element  140  is substantially composed of two metal strips attached to each other (for example, bimetallic strips), and the temperature control element  140  is substantially immersed in the cooling liquid, so the temperature control element  140  can cause deformation based on the temperature of cooling liquid. In more detail, when the temperature of the cooling liquid is lower than a temperature threshold, the temperature control element  140  will bend toward a side of the metal strip having a larger coefficient of thermal expansion. When the temperature of the cooling liquid is higher than the temperature threshold, the temperature control element  140  will bend toward a side of the metal strip with the smaller coefficient of thermal expansion. By this feature, the temperature control element  140  can cause the deformation based on the temperature of the cooling liquid, and to clog and be separated from the liquid inlet hole  132 A through the stop portion  146  disposed on the temperature control element  140 , so as to achieve the purpose of controlling the flow rate of the cooling liquid. 
     In the cooling liquid flow control device  100  of the present disclosure, as shown in  FIG.  7   , when the temperature of the cooling liquid is lower than the temperature threshold, the temperature control element  140  bends toward a side of the second metal strip  144 , causing the stop portion  146  clogs the liquid inlet hole  132 A so as not to communicate the liquid inlet pipe IT and the first sub-cavity C 1 . In a usage scenario, when the heating element located under the heat dissipation bottom plate  110  and in contact with the bottom surface  110   b  generates a relatively little amount of waste heat due to being in an idle state, the temperature of the cooling liquid is lower than the temperature threshold, and the temperature control element  140  bends upward (as shown in  FIG.  7   ) to clog the liquid inlet hole  132 A. Since the stop portion  146  clogs the entire liquid inlet hole  132 A, the cooling liquid from the liquid inlet pipe IT cannot temporarily enter the first sub-cavity C 1  through the liquid inlet hole  132 A. 
     In the cooling liquid flow control device  100  of the present disclosure, as shown in  FIG.  8   , when the temperature of the cooling liquid is higher than the temperature threshold, the temperature control element  140  bends toward a side of the first metal strip  142 , causing the stop portion  146  is separated from the liquid inlet hole  132 A to communicate the liquid inlet pipe IT and the first sub-cavity C 1 . In a usage scenario, when the heating element located under the heat dissipation bottom plate  110  generates a relatively large amount of waste heat due to being in a full load state and, the temperature of the cooling liquid is higher than the temperature threshold, and the temperature control element  140  bends downward (as shown in  FIG.  8   ) to be separated from the liquid inlet hole  132 A. Since the stop portion  146  is separated from the liquid inlet hole  132 A, the cooling liquid from the liquid inlet pipe IT can enter the first sub-cavity C 1  through the liquid inlet hole  132 A. As shown in  FIG.  8   , the maximum extent that the temperature control element  140  bends toward a side of the first metal strip  142  is that the extension direction of the temperature control element  140  is parallel to the extension direction of the heat dissipation bottom plate  110  (that is, the temperature control element  140  contacts the top surface  110   a  of the heat dissipation bottom plate  110  and is parallel thereto). 
     In the cooling liquid flow control device  100  of the present disclosure, when the temperature of the cooling liquid is between the temperature of the cooling liquid in the embodiment of  FIG.  7    and the temperature of the cooling liquid in the embodiment of  FIG.  8   , The temperature control element  140  causes the stop portion  146  partially clogs the liquid inlet hole  132 A to communicate the liquid inlet pipe IT and the first sub-cavity C 1 . In a usage scenario, when the heating element located under the heat dissipation bottom plate  110  is in a partial load state and does not generate that much waste heat in a full load state, so that the temperature of the cooling liquid is lower than that of the cooling liquid in a full load state. The temperature in turn causes the stop portion  146  to clog a part of the liquid inlet hole  132 A. Since the stop portion  146  clogs the part of the liquid inlet hole  132 A, the cooling liquid from the liquid inlet pipe IT can enter the first sub-cavity C 1  through the liquid inlet hole  132 A at a relatively low flow rate. 
     Through the above operations, the cooling liquid flow control device  100  can control the flow rate of the cooling liquid based on the temperature of the cooling liquid in the cavity C, so as to achieve the effect of saving power. 
     In some embodiments, the temperature control element  140  is substantially disposed in the first sub-cavity C 1 , but the present disclosure is not limited thereto. In some embodiments, the temperature control element  140  may also be disposed in the second sub-cavity C 2 . 
     In some embodiments, the stop portion  146  is disposed near the liquid inlet hole  132 A to clog and be separated from the liquid inlet hole  132 A, but the present disclosure is not limited thereto. In some embodiments, the stop portion  146  may also be disposed near the liquid outlet hole  132 B to clog and be separated from the liquid inlet hole  132 A. 
     In some embodiments, as shown in  FIG.  1   ,  FIG.  2   ,  FIG.  6   ,  FIG.  7   , and  FIG.  8   , the fixing element S 2  includes elements such as springs and screws, but the present disclosure is not limited thereto. In some embodiments, the fixing element S 2  may not include a spring. Although the present disclosure discloses that the fixing holder  120  is connected to the substrate by means of locking, the present disclosure does not intend to limit the structure, method, or means for connecting the fixing holder  120  to the substrate. 
     In some embodiments, as shown in  FIG.  1   ,  FIG.  2   ,  FIG.  5   ,  FIG.  7   , and  FIG.  8   , the fixing element S 1  is substantially a screw. Although the present disclosure discloses that the heat dissipation bottom plate  110  and the fixing holder  120  are connected to each other by means of locking (for example, the heat dissipation bottom plate  110  and the fixing holder  120  are locked to each other through the fixing element S 1 ), the present disclosure does not intend to limit the structure, method or means of connecting heat dissipation bottom plate  110  and the fixing holder  120  to each other. 
     In some embodiments, the composition of the cooling liquid may be liquid water (H 2 O), but the present disclosure is not limited thereto. In some embodiments, the composition of the cooling liquid may be ethylene glycol (C 2 H 6 O 2 ) or propylene glycol (C 3 H 8 O 2 ). The above is merely an example for simple description, and the present disclosure does not intend to limit the composition of the cooling liquid. 
     In some embodiments, the heat dissipation bottom plate  110  and the cooling module  130  are substantially separated from each other, but the present disclosure is not limited thereto. In some embodiments, the heat dissipation bottom plate  110  and the cooling module  130  may be integrally formed rather than separately provided. For example, the heat dissipation bottom plate  110  and the cooling module  130  can be integrally formed into a water-cooling case body with a cavity C. 
     In some embodiments, the heat dissipation bottom plate  110  and the cooling module  130  are substantially tightly connected. Alternatively, in some embodiments, the heat dissipation bottom plate  110  and the cooling module  130  may be adhesively connected to each other. Alternatively, in some embodiments, the heat dissipation bottom plate  110  and the cooling module  130  may be buckled and connected to each other. The foregoing is merely examples for simple description, and the present disclosure does not intend to limit the structure, method, or means of connecting the heat dissipation bottom plate  110  and the cooling module  130  to each other. 
     In some embodiments, the first metal strip  142  and the second metal strip  144  may be a combination of metal materials such as copper/aluminum or copper/stainless steel. The present disclosure does not intend to limit the material combination of the first metal strip  142  and the second metal strip  144 . It should be noted that the material combination of the first metal strip  142  and the second metal strip  144  must also consider whether it will chemically react with the cooling liquid to cause rust or damage to the temperature control element  140 . 
     In some embodiments, the temperature control element  140  may include at least two metal strips with different coefficient of thermal expansions. 
     In some embodiments, the stop portion  146  may be a flexible material such as plastic, rubber, or cork to clog the liquid inlet hole  132 A more tightly. The foregoing is only an example for simple description, and the present disclosure does not intend to limit the material of the stop portion  146 . 
     In some embodiments, one end of the temperature control element  140  may be fixed to the pressing block  138 . For example, the pressing block  138  may have a downwardly extending bump passing through the positioning hole  148  to position the temperature control element  140 . In the embodiment in which the pressing block  138  has a bump, the heat dissipation bottom plate  110  does not include the positioning column  112 . The present disclosure does not intend to limit the position where the temperature control element  140  is disposed on the inner surface of the cavity C. 
     In some embodiments, the temperature control element  140  may be locked to the inner surface of the cavity C. Alternatively, in some embodiments, the temperature control element  140  may be adhered to the inner surface of the cavity C. Alternatively, in some embodiments, the temperature control element  140  may be buckled on the inner surface of the cavity C. The present disclosure does not intend to limit the structure, method, or means for the temperature control element  140  to connect to the inner surface of the cavity C. 
     From the above detailed description of the specific embodiments of the present disclosure, it can be clearly seen that in the cooling liquid flow control device of the present disclosure, since the temperature control element utilizes the characteristics of bimetallic strip generating deformation based on the temperature of the cooling liquid, the stop portion of the temperature control element can clog, partially clog, or be separated from the liquid inlet hole to achieve the purpose of controlling the flow rate of the cooling liquid. In the cooling liquid flow control device of the present disclosure, since the bimetallic strip is used as the material of the temperature control element, it can not only achieve the power saving effect of the cooling liquid flow control device, but also effectively reduce the installation space of the liquid cooling device. 
     In an embodiment of the present disclosure, the cooling system of the present disclosure can be applied to a server, which can be used for artificial intelligence (AI) computing, edge computing, or used as a 5G server, cloud server or vehicle networking server. 
     Although the present disclosure has been disclosed as above in the embodiment manner, it is not intended to limit the present disclosure. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. Therefore, the scope of the present disclosure shall be subject to the scope of the attached claims.