Abstract:
Embodiments of the present invention provide a cooling apparatus for cooling an electronic component to which the cooling apparatus is attached. In one embodiment, an apparatus for cooling an electronic component comprises a pump; a cooling member configured to be disposed adjacent the electronic component, the cooling member including a plurality of protrusions over which a cooling fluid circulates to dissipate heat generated by the electronic component; a coolant flow control housing coupled to the cooling member, the coolant flow control housing including a distributed flow path over the plurality of protrusions for the cooling fluid to enter the cooling member in a distributed manner over the plurality of protrusions, and an exit path for the cooling fluid to exit the cooling member; and a serialization housing connected between the coolant flow control housing and the pump, the serialization housing including a pump inlet to direct the cooling fluid from the exit path of the coolant flow control housing to the pump for pumping the cooling fluid out of the apparatus.

Description:
FIELD OF THE INVENTION 
       [0001]    The invention relates generally to an apparatus for cooling an electronic component and, more particularly, to a set of housings enabling the construction of a compact water-cooled cold plate with an integrated pump having high performance and reliability. 
       BACKGROUND OF THE INVENTION 
       [0002]    With the recent onslaught of improvements in computer technology, the thermal load generated by personal computers has increased considerably. In order to ensure proper operation of the heat generating devices in the computer including, but not limited to, central processing units, video graphics processing units, and memory modules, liquid cooling systems have become widely used as a means to effectively dissipate the heat generated by these components. As the complexity of the liquid cooling systems increases, there also exists a need to simplify such systems. 
         [0003]    One type of cooling system employs a cold plate that is attached to a housing to form a cavity equipped with one or more inlet and outlet ports to circulate a coolant inside the cavity. The cold plate may be machined so that one of its faces forms a plurality of pins or fins. Such a device is also known as a water-block. A recirculation pump provides circulation of the coolant inside of the water-block. Water-blocks and pumps are separate units. Examples of pumps are found in U.S. Pat. Nos. 6,736,616, 6,713,918, and 6,897,596 B2. 
       SUMMARY OF THE INVENTION 
       [0004]    Embodiments of the present invention provide a cooling apparatus for cooling an electronic component to which the cooling apparatus is attached. The cooling apparatus has a simplified design that is achieved by combining several of its components into one, thus reducing the occupied space and improving flow rate and overall reliability of the cooling apparatus. More specifically, a set of housings enable the construction of a water-cooled cold plate including an integrated or built-in pump used for heat dissipation of electronic devices such as central processing units. The integrated cold plate and pump apparatus may be used in combination with a heat exchanger to form a liquid cooling system to dissipate the heat generated by computer components such as central processing units, video graphics processing units and memory modules. 
         [0005]    The present invention enables the construction of a device including a water-cooled cold plate and a recirculation pump described herein so as to combine them in order to form a single device which can be affixed onto a central processing unit for heat dissipation purposes. To this effect, a set of two housings is disclosed hereafter that represents one possible embodiment of the invention. It is possible to envision variations on the design that would physically combine the two housings into a single part. 
         [0006]    In accordance with an aspect of the present invention, an apparatus for cooling an electronic component comprises a pump; a cooling member configured to be disposed adjacent the electronic component, the cooling member including a plurality of protrusions over which a cooling fluid circulates to dissipate heat generated by the electronic component; a coolant flow control housing coupled to the cooling member, the coolant flow control housing including a distributed flow path over the plurality of protrusions for the cooling fluid to enter the cooling member in a distributed manner over the plurality of protrusions, and an exit path for the cooling fluid to exit the cooling member; and a serialization housing connected between the coolant flow control housing and the pump, the serialization housing including a pump inlet to direct the cooling fluid from the exit path of the coolant flow control housing to the pump for pumping the cooling fluid out of the apparatus. 
         [0007]    In some embodiments, the plurality of protrusions of the cooling member cover an area having a length and a width. The coolant flow control housing includes a flow outlet port to provide the distributed flow path over the plurality of protrusions, the flow outlet port having a generally rectangular shape with a length that is at least about 50% of the length of the area of the plurality of protrusions. The area of the plurality of protrusions is generally square with the length about equal to the width. The plurality of protrusions of the cooling member cover an area having a length and a width, and the coolant flow control housing includes a flow inlet port to provide the exit path for the cooling fluid to exit the cooling member, the flow inlet port having a generally rectangular shape with a length that is at least about 50% of the length of the area of the plurality of protrusions. The flow outlet port overlaps a first portion of the area of the plurality of protrusions on a first side and the flow inlet port overlaps a second portion of the area of the plurality of protrusions on a second side opposite from the first side. The coolant flow control housing includes a generally triangular flow inlet cavity with a vertex that is fluidly coupled to a cooling fluid inlet, and the flow outlet port is disposed adjacent an edge of the generally triangular flow inlet cavity opposite from the vertex. 
         [0008]    In specific embodiments, the coolant flow control housing includes a retention mechanism to attach the apparatus to the electronic component. The serialization housing includes an inlet port to receive a cooling fluid into the apparatus and direct the cooling fluid to the distributed flow path of the coolant flow control housing, and an outlet port for the cooling fluid to exit the apparatus after circulating over the plurality of protrusions of the cooling member. The pump comprises an impeller and an impeller port to receive the cooling fluid. The serialization housing includes a hydraulic cavity to receive the impeller, the hydraulic cavity have a curved wall. The pump inlet is coupled between the exit path of the coolant flow control housing and the impeller port to direct the cooling fluid from the exit path of the coolant flow control housing to the impeller port. The outlet port of the serialization housing is disposed generally tangential to the curved wall of the hydraulic cavity. The cooling member includes a flat surface on a back side of a surface containing the plurality of protrusions, the flat surface being configured to contact the electronic component to be cooled. 
         [0009]    Another aspect of the present invention is directed to an apparatus for coupling a pump with a cooling member for cooling an electronic component to form an integrated cooling device. The apparatus comprises a coolant flow control housing configured to be coupled to the cooling member. The coolant flow control housing includes a flow inlet cavity which diverges from a vertex to an opposite edge disposed opposite from the vertex, the vertex being fluidly coupled to a cooling fluid inlet, the opposite edge having a length substantially larger than a size of the cooling fluid inlet. The coolant flow control housing further includes a generally rectangular flow outlet port disposed adjacent the opposite edge of the flow inlet cavity opposite from the vertex to provide a distributed flow path over the cooling member, and an exit path for the cooling fluid to exit the cooling member. A serialization housing is configured to be connected between the coolant flow control housing and the pump. The serialization housing includes a pump inlet to direct the cooling fluid from the exit path of the coolant flow control housing to the pump for pumping the cooling fluid out of the apparatus. 
         [0010]    In some embodiments, the flow inlet cavity of the coolant flow control housing is generally triangular with the vertex and the opposite edge disposed opposite from the vertex. The serialization housing includes an inlet port to receive a cooling fluid into the integrated cooling device and direct the cooling fluid to the vertex of the flow inlet cavity of the coolant flow control housing, and an outlet port for the cooling fluid to exit the integrated cooling device after circulating over the cooling member. The serialization housing includes a hydraulic cavity to receive a portion of the pump, the hydraulic cavity has a curved wall, and the outlet port of the serialization housing is disposed generally tangential to the curved wall of the hydraulic cavity. 
         [0011]    Another aspect of the invention is directed to an apparatus for coupling a pump with a cooling member for cooling an electronic component to form an integrated cooling device. The cooling member includes a plurality of protrusions over which a cooling fluid circulates to dissipate heat generated by the electronic component. The plurality of protrusions of the cooling member cover an area having a length and a width. The apparatus comprises a coolant flow control housing configured to be coupled to the cooling member. The coolant flow control housing includes a generally rectangular flow outlet port to provide a distributed flow path over the plurality of protrusions for the cooling fluid to enter the cooling member in a distributed manner over the cooling member, and an exit path for the cooling fluid to exit the cooling member. A serialization housing is configured to be connected between the coolant flow control housing and the pump. The serialization housing includes a pump inlet to direct the cooling fluid from the exit path of the coolant flow control housing to the pump for pumping the cooling fluid out of the apparatus. 
         [0012]    In some embodiments, the generally rectangular flow outlet port of the coolant flow control housing has a length that is at least about 50% of the length of the area of the plurality of protrusions of the cooling member. The coolant flow control housing includes a flow inlet port to provide the exit path for the cooling fluid to exit the cooling member. The flow inlet port has a generally rectangular shape with a length that is at least about 50% of the length of the area of the plurality of protrusions of the cooling member. 
         [0013]    These and other aspects of the invention are described in further detail below and shown in the accompanying drawings. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is an exploded perspective view of a cooling apparatus having a water-cooled cold plate with an integrated pump in accordance with an embodiment of the present invention. 
           [0015]      FIG. 2  is a side elevational view of a centrifugal pump. 
           [0016]      FIG. 3  is a cross-sectional view of the centrifugal pump of  FIG. 2  along line A-A. 
           [0017]      FIG. 4  is a top plan view of the centrifugal pump of  FIG. 2 . 
           [0018]      FIG. 5  is a perspective view of the centrifugal pump of  FIG. 2 . 
           [0019]      FIG. 6  is a perspective view of a serialization housing in a preferred embodiment of the cooling apparatus of  FIG. 1 ; 
           [0020]      FIG. 7  is a perspective view of a cold plate in the cooling apparatus of  FIG. 1 . 
           [0021]      FIG. 8  is a perspective view of the cooling apparatus of  FIG. 1 . 
           [0022]      FIG. 9  is a side elevational view of the cooling apparatus of  FIG. 1 . 
           [0023]      FIG. 10  is a cross-sectional view of the cooling apparatus of  FIG. 8  along line A-A. 
           [0024]      FIG. 11  is a top plan view of the cooling apparatus of  FIG. 1 . 
           [0025]      FIG. 12  is a perspective view of a coolant flow control housing in the cooling apparatus of  FIG. 1 . 
           [0026]      FIG. 13  is a partial cross-sectional perspective view of the cooling apparatus of  FIG. 1 . 
           [0027]      FIG. 14  is another partial cross-sectional perspective view of the cooling apparatus of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0028]      FIG. 1  is an exploded perspective view of a cooling apparatus  10  having a water-cooled cold plate with an integrated pump in accordance with an embodiment of the present invention. The cooling apparatus  10  includes a pump body  1  containing a motor composed of a stator, an electronic control circuit board, and a rotor which is also called an impeller. The impeller spins on a single ceramic bearing and entrains the flow in and out of the device assembly. A serialization housing  15  includes a housing body, an inlet fitting, and an outlet fitting providing a flow path in and out of the cooling apparatus  10 . A cavity of the serialization housing  15  encloses the rotor located in the pump  1 . A coolant flow control housing  14  directs the flow coming from the pump  1  to a cold plate  17 , and then out to a heat exchanger that may be situated downstream thereof. The cold plate  17  is configured to attach onto an electronic component such as the central processing unit. The cold plate  17  contains a plurality of pins or fins creating channels therebetween through which the coolant circulates, thus efficiently dissipating the heat generated by the central processing unit into the fluid. 
         [0029]      FIG. 2  is a side elevational view of a centrifugal pump  100 .  FIG. 3  is a cross-sectional view of the centrifugal pump  100  of  FIG. 2  along line A-A. In the centrifugal pump  100 , a fluid enters at the center of the impeller rotational axis, is propelled radially by the high velocity and circular motion of the impeller, and exits tangentially to the pump impeller cavity. The pump  100  includes a pump main body or housing  101 , and a bearing mechanism  109  to support an impeller  103 . The pump  100  further includes a stator and electronic control components (not shown). 
         [0030]    A pump housing cover  102  includes a hydraulic cavity  108 , and a fluid inlet  104  and a fluid outlet  107  to direct the fluid in and out of the pump  100 . The pump motor impeller  103  includes an impeller inlet  105  situated at its geometric center, and a plurality of blades  106  situated on its upper body. The outermost diameter of the impeller  103  may be between about 31 mm and about 44 mm. The fluid inlet port  104  is disposed in the hydraulic cavity  108  of the pump housing cover  102 , and may have a diameter of between about 6 mm and about 13 mm. The fluid outlet port  107  is disposed adjacent the outer diameter of the hydraulic cavity  108  of the pump housing cover  102 , and may have a diameter of between about 6 mm and about 13 mm. The hydraulic cavity  108  of the pump housing cover  102  may have an outermost diameter of between about 35 mm and about 48 mm. 
         [0031]      FIG. 4  is a top plan view and  FIG. 5  is a perspective view of the centrifugal pump  100 . The pump  100  has a pump outlet port  110  and a pump inlet port  111 .  FIG. 5  shows a directional representation (arrow  113 ) of the fluid entering the pump  100  at the pump inlet port  111 , and a directional representation (arrow  112 ) of the fluid exiting the pump  100  at the pump outlet port  110 . As described below, the centrifugal pump  100  can be adapted for use in the cooling apparatus  10  of  FIG. 1  by replacing the pump housing cover  102  and the associated pump inlet port  111  and pump outlet port  110  with the serialization housing  15  of  FIG. 1 . 
         [0032]      FIG. 6  is a perspective view of the serialization housing  15  for serializing the cold plate  17  and the pump  1 . The body of the serialization housing  15  has a generally square shape and may have a length of between about 50 mm and about 70 mm. The body of the serialization housing  15  may have a rectangular shape or other shapes in alternative embodiments. The flow egress or circular outlet port  222  originates from and is tangential to the circular wall formed by the hydraulic cavity  225 , completely traversing the serialization housing  15 . The outlet port  222  may have a diameter of between about 5 mm and about 8 mm. The flow ingress or circular inlet port  223 , which leads to the flow inlet cavity  219  of the coolant flow control housing  14 , completely traverses the serialization body  15 , and may have a diameter of between about 5 and about 8 mm. The flow ingress or circular pump inlet port  224 , which leads to the impeller inlet  205 , completely traverses the serialization body  15 , and may have a diameter of between about 5 mm and about 8 mm. The hydraulic cavity  225  has a generally spiraled shape, a relatively small radius which may be between about 15 mm and about 25 mm, and a depth of between about 6 and about 8 mm. 
         [0033]      FIG. 7  is a perspective view of the cold plate  17  in the cooling apparatus  10  of  FIG. 1 . The cold plate body  117  has a square shape, but may have a rectangular shape or other shapes in alternative embodiments. The lower face of the cold plate body  117  is a flat surface providing a thermal interface joint or contact to an electronic component such as a central processing unit. The upper surface of the cold plate body  117  contains a plurality of protrusions such as pins or fins  118  creating channels through which a coolant may circulate, thus efficiently dissipating the heat generated by the central processing unit into the fluid. The plurality of pins or fins  118  are a matrix of features machined, molded, or extruded into the upper face of the cold plate body  117 , and function to increase the overall surface area in contact with the cooling fluid, thereby enhancing the thermal exchange between the cold plate  17  and the cooling fluid. The length and width of the matrix of features  118  may each be between about 25 mm and about 45 mm, and the height of the features  118  may be between about 1 mm and about 10 mm. 
         [0034]      FIG. 8  is a perspective view of the cooling apparatus  10  of  FIG. 1 . In order to integrate the pump  100  of  FIGS. 2-5  to the cold plate  17  that attaches directly onto an electronic component such as a central processing unit while preserving the flow characteristics of the pump, and at the same time optimizing the flow pattern over the cold plate  17  so as to maximize the heat exchange characteristics of the cold plate  17 , the pump housing cover  102  of  FIGS. 2-5  is replaced by the serialization housing  15  of  FIG. 1  and  FIG. 6 . The primary function of the serialization housing  15  is to serialize the cold plate  17  and the pump  1  by providing a flow path to the impeller inlet  105  of the impeller  103 . The function of the coolant flow control housing  14  is to provide a distributed flow path over the cold plate  17 , an exit path to the coolant flow back to the serialization housing  15 , and a retention mechanism to attach the cooling apparatus  10  onto an electronic component such as a central processing unit. 
         [0035]      FIG. 9  is a side elevational view of the cooling apparatus  10  of  FIG. 1 .  FIG. 10  is a cross-sectional view of the cooling apparatus  10  of  FIG. 9  along line A-A.  FIG. 11  is a top plan view of the cooling apparatus  10 . The pump  1  includes a pump main body or housing  201 , and a bearing mechanism  209  to support an impeller  203 . The pump  1  further includes a stator and electronic control components (not shown). The impeller  203  has an impeller inlet  205  and a plurality of blades  206 . The impeller inlet  205  is situated at the geometric center of the impeller  203 . The plurality of blades  206  form the hydraulic body of the impeller  203 . The bearing mechanism  209  is disposed between the pump main body  201  and the impeller  203 . 
         [0036]    The coolant flow control housing  14  provides a distributed flow path over the plurality of pins  118  of the cold plate body  117  of the cold plate, an exit path to the coolant flow to the serialization housing  15 , and a retention mechanism to attach the cooling apparatus  10  onto an electronic component such as a central processing unit. The coolant flow control housing  14  includes a housing body  214 , a flow inlet cavity  219 , and a flow outlet cavity  220 . The primary function of the serialization housing  15  is to serialize the cold plate  17  and the pump  1  by providing a flow path into the impeller inlet  205  of impeller  203 , and an ingress flow path from a heat exchanger that may be located upstream of the cooling apparatus  10 . An inlet fitting  216  is attached to an inlet port  223  of the serialization housing  15  by mean of a chemical or other bonding method or the like. An outlet fitting  221  ( FIG. 9 ) is attached to an outlet port of the serialization housing  15  by means of a chemical or other bonding method or the like, thereby providing an egress path to the coolant flow to a heat exchanger that may be located downstream of the cooling apparatus  10 . The inlet port  223  of the serialization housing  15  directs flow to an apex of a flow inlet cavity  219  of the coolant flow control housing  14  as described in greater detail below. In addition, a pump inlet port  224  of the serialization housing  15  directs flow of the cooling fluid away from the cold plate  17  and to the impeller inlet  205  of the impeller  203  in pump  1 . The serialization housing  15  further includes a hydraulic cavity  225 . 
         [0037]    As seen in  FIG. 12 , the flow inlet cavity  219  of the coolant flow control housing  14  has a generally triangular shape and has opposite walls that progressively diverge from a vertex  227  to rejoin a generally rectangular flow outlet port  226 , thus distributing the flow over the entire port opening. The flow outlet port  226  is disposed adjacent the opposite edge of the flow inlet cavity  219  disposed opposite from the vertex  227 . The length of the flow outlet port  226  is at least equal to about 50% of that of the pins  118  of the cold plate  17 , thus providing a distributed flow path onto the pins or fins  118 . A flow outlet cavity  220  of a generally rectangular shape includes a flow inlet port  228  of rectangular shape the length of which is at least equal to about 50% of that of pins  118  of cold plate  17 . The primary function of the coolant flow control housing  14  is to provide a distributed flow path over the plurality of pins  118  of the cold plate  17 . 
         [0038]    The coolant flow control housing  14  has a generally square shape featuring four or more feet extending at or about the corners or other areas of the housing  14  so as to provide a retention mechanism to attach the cooling apparatus  10  to an electronic component such as a central processing unit. The coolant flow control housing  14  may have a length and a width of between about 50 mm and about 70 mm. The generally rectangular flow outlet port  226  has a length that is at least about 50% of that of the pins or fins matrix  118  of the cold plate  17 , and a width that is between about 2 mm and about 8 mm. The generally rectangular flow inlet port  228  has a length that is at least about 50% of that of the pins or fins matrix  118  of cold plate  17 , and a width that is between about 2 mm and about 8 mm. 
         [0039]      FIG. 13  is a partial cross-sectional perspective view of the cooling apparatus  10  of  FIG. 1  illustrating the cooling fluid flow path from the device inlet and up to the device impeller  203 . The cooling fluid enters the device inlet fitting  216  of the serialization housing  15 , travels and fills the inlet flow cavity  219  of the coolant flow control housing  14 , enters the flow outlet port  226 , where it is then distributed over/through the plurality of protrusions—i.e. where it travels through the pins or fins  118  of the cold plate  17 . The cooling fluid then enters and fills the flow outlet cavity  220  through the inlet port  228  of the coolant flow control housing  14 , and egresses through the pump inlet port  224  of the serialization housing  15  to the pump impeller  203 . 
         [0040]      FIG. 14  is another partial cross-sectional perspective view of the cooling apparatus  10  of  FIG. 1  illustrating the cooling fluid flow path from the pump impeller  203  and up to the device outlet fitting  216  of the serialization housing  15 , where the cooling fluid enters the impeller inlet port  205  of impeller  203 , is distributed and propelled by centrifugal force through the channels created by blades  206  against the circular walls of hydraulic cavity  225  of the serialization housing  15 , enters the outlet port  222  of the serialization housing  15 , and exits through the outlet fitting  216  of the serialization housing  15  towards a heat exchanger that may be located downstream of the cooling apparatus  10 . 
         [0041]    Although preferred embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this invention. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.