Abstract:
A cooling apparatus is for dissipating heat from an electronic device. The cooling apparatus includes a casing, an impeller, and a motor. The casing is for absorbing the heat and allowing coolant to flow therein. The impeller is received in the casing. The motor is received in the casing, and is for providing a force to drive the impeller to rotate to force the coolant to flow. The coolant flows between the casing and the motor to take the heat away.

Description:
BACKGROUND 
     1. Field of the Invention 
     The present invention generally relates to cooling apparatuses, and particularly to a cooling apparatus utilizing coolant flow and agitation. 
     2. Description of Related Art 
     In the past, heat generated by a typical central processing unit (CPU) of a computer can be adequately removed by a conventional cooling apparatus utilizing heat sinks and air fans. However, because of recent advances in technology, chip density and CPU speed have increased resulting in more heat being given off by the CPU, as such the conventional cooling apparatus can no longer efficiently remove heat from the CPU. 
     In order to increase the efficiency in removing heat, coolant such as water is used to help cool the CPU. A coolant-cooling apparatus uses a circulating channel between a heat source and a heat-dissipation part, and the coolant flows in the circulating channel. The coolant absorbs heat from the heat source, and transports the heat to the heat-dissipation part. The heat-dissipation part dissipates the heat to air. Furthermore, the coolant-cooling apparatus also utilizes a pump to drive the coolant to flow circularly in the circulating channel. 
     However, the heat source, the heat-dissipation part, and the pump are disposed independently from each other in different position along the circulating channel, resulting in the coolant-cooling apparatus occupying valuable space in the computer. Thus, the coolant-cooling apparatus occupying a large space in a computer is and will be a shortcoming as the computer gets smaller. 
     Therefore, improvements for a cooling apparatus are needed in the industry to address the aforementioned deficiency. 
     SUMMARY 
     A cooling apparatus is for dissipating heat from an electronic device. The cooling apparatus includes a casing, an impeller, and a motor. The casing is for absorbing the heat and allowing coolant to flow therein. The impeller is received in the casing. The motor is received in the casing, and is for providing a force to drive the impeller to rotate to force the coolant to flow. The coolant flows between the casing and the motor to take the heat away. 
     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. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a disassembled view of a cooling apparatus in accordance with an exemplary embodiment. 
         FIG. 2  is disassembly view of the cooling apparatus of  FIG. 1 , viewed from another side. 
         FIG. 3  is an assembly view of the cooling apparatus of  FIG. 1 . 
         FIG. 4  is a cross-sectional view taken along line IV-IV of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made to the drawings to describe a preferred embodiment of the present cooling apparatus. 
     Referring to  FIGS. 1 ,  2 ,  4 , a cooling apparatus  100  in accordance with an exemplary embodiment is used to cool a central processing unit (CPU) (not shown) using water as coolant. The cooling apparatus  100  includes a casing  10 , a motor  20 , and an impeller  30 . The motor  20  and the impeller  30  are received in the casing  10 . The coolant is received in a space enclosed between the casing  10  and the motor  20 . The motor  20  is configured for rotating the impeller  30 . A plurality of vanes  315  is formed on the circular periphery of the impeller  20 . When the motor  20  rotates, it drives the impeller  30  to also rotate, thus the coolant is forced by the vanes  315  to flow. 
     The casing  10  includes a base  11 , a lid  13 , a sealed loop  15 , an inner gasket  17 , and an outer gasket  19 . The base  11  is used for contacting with the CPU to absorb heat from the CPU, and supporting the other components. The lid  13  is used for cooperating with the base  11  to enclose the motor  20  and the impeller  30 . 
     The base  11  includes an annular wall  111  to position the lid  13 . The lid  13  includes a circular top board  130 , a hollow cylindrical sidewall  132  with an inner side surface  137 . The sidewall  132  surrounds the top board  130  and perpendicularly connects with the top board  130 . The lid  13  further includes an intake  131  by which the coolant is admitted into the casing  10 , and an outlet  133  through which the coolant flows out of the casing  10 . The intake  131  is defined in the center of the top board  130  for connecting a water pipe (not labeled). The outlet  133  is defined in the sidewall  132  for connecting another water pipe (not labeled). A speedup member  135  is mounted at the joint between the top board  130  and the sidewall  132 . The speedup member  135  extends surrounding the inner side surface  137 , and the thickness thereof gradually decreases from one end defining the outlet  133  to the other end, thus the thickness of the other end is zero. The sealed loop  15 , the inner gasket  17 , and the outer gasket  19  are clamped between the annular wall  111  and the lid  13  to prevent the coolant from flowing out of the casing  10 . 
     The sealed loop  15  defines an outer recess  157  in its outer side surface (not labeled) and an inner recess  159  in its inner side surface (not labeled). The inner gasket  17  is embedded in the inner recess  159  and is sleeved around the annular wall  111 . The outer gasket  19  is sleeved on the outer recess  157  and is compacted against the inner side surface  137  of the lid  13 . The base  11  also defines a first hole  113  within a range of the annular wall  111  for leading an electrical wire  231  (referring to  FIG. 4 ) to pass therethrough. In the embodiment, the electrical wire  231  is used to transmit electrical signals to the motor  20 . 
     The motor  20  includes a sealed device  21 , a drive coil  23  received in the sealed device  21 , a bearing  25 , and an annular magnet  27  sleeved around the sealed device  21 . The annular magnet  27  can be rotated with respected to the sealed device  21 . 
     The sealed device  21  includes a first cap  211 , a supporting board  213  cooperating with the first cap  211  to protect the drive coil  23  from the coolant, and an annular gasket  215  elastically clamped between the first cap  211  and the supporting board  213  to closely seal a gap therebetween. The supporting board  213  defines a second hole  2131  corresponding to the first hole  113 . The electrical wire  231  is electrically connected to the drive coil  23  through the second hole  2131 . Therefore, the drive coil  23  is protected from the coolant using a combination of the first cap  211 , the supporting board  213 , and the annular gasket  215 . 
     The first cap  211  includes an inner lid surface  2111 , an outer lid surface  2113 , and a bearing housing  2115  formed in the center of the inner lid surface  2111  and the center of the outer lid surface  2113 . When viewed from a side of the inner lid surface  2111 , the bearing housing  2115  extends vertically from the center of the inner lid surface  2111  as a post, while viewed from a side of the outer lid surface  2113 , the bearing housing  2115  is recessed downwardly from the center of the outer surface  2113  to define a cavity thereof. 
     The drive coil  23  sleeves around the bearing housing  2115  via a guiding hole (not labeled) in the center of the drive coil  23 . The bearing  25  is received in the bearing housing  2115 . The annular magnet  27  is tightly wedged into the impeller  30 . 
     The impeller  30  includes a second cap  31  and a shaft  33  protruding vertically from the center of a coping  313  of the second cap  31 . The second cap  31  includes the coping  313 , an annular wall  311  extending downwardly from the coping  313 , and the vanes  315  formed on circular periphery of the annular wall  311 . The annular magnet  27  of the motor  20  is tightly wedged into the second cap  31 . When the motor  20  operates, the annular magnet  27  is driven by a magnetic force generated by the drive coil  23  to rotate, thereby the second cap  31  is also rotated with the annular magnet  27 . The shaft  33  passes through a through hole  251  of the bearing  25 . 
     Therefore, the bearing housing  2115  of the sealed device  21 , the bearing  25 , and the shaft  33  of the impeller  30  collectively form a rotatable device to help the impeller  30  rotate with respect to the sealed device  21 . 
     In operation, referring to  FIGS. 3 ,  4 , the coolant flows into the casing  10  via the intake  131 , and fills up a space between the casing  10  and the sealed device  21 . Power is supplied to the drive coil  23 , and the drive coil  23  generates the magnetic force to rotate the annular magnet  27 . Then the second cap  31  is rotated by the annular magnet  27 , thus the vanes  315  rotates and pushes the coolant to flow. The cooling apparatus  100  is set on the CPU, with the base  11  closely attached to the CPU to absorb the heat generated from the CPU. The coolant takes the heat away from the base  11 , and flows out of the casing  10  via the outlet  133 . 
     As mentioned above, the cooling apparatus  100  utilizes the casing  10  to absorb the heat, and utilizes the motor  20  to force the coolant to take the heat away, and especially the motor  20  is received in the casing  10 . Therefore, the cooling apparatus  100  has a comparative small size that can be used in computers with small footprints. Furthermore, the thickness of the speedup member  135  gradually decreases to zero along the rotation direction of the impeller  30 , thus the outlet  133  faces the flow direction of the coolant to accelerate the speed of the coolant flowing out of the casing  10  from the outlet  133 . 
     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.