Patent Publication Number: US-2022225533-A1

Title: Apparatus for heat management in an electronic device

Description:
FIELD 
     The present disclosure relates to an electronic device and an associated heat management device and assembly mechanism therein. 
     BACKGROUND 
     The present disclosure may be applicable to most electronic devices that include a heat management mechanism. Such electronic apparatuses or devices in the field are described as being typically assembled apparatuses having a plurality of walls and a top and a bottom surface that is generally designed to encase and protect interior components. Some exemplary electronic devices include, but are not limited to, set-top boxes, over-the-top media devices, gateways, and the like. 
     Most designs of these electronic apparatuses are such that the top plan view shape is rectangular, and the apparatuses are horizontal electronic apparatuses in which the height of the apparatuses is smaller than the horizontal width of the front wall, rear wall, and the side walls. Such horizontal devices are mechanically stable given their wide bases and their tops being planar horizontal structures. However, the form factor of horizontal devices requires a significant amount of shelf space and may not be convenient for electronic devices that may stand alone and/or may be placed in a location with more vertical than horizontal space available. 
     New vertical electronic apparatuses are more prevalent in design for the consumer electronics and communication devices market in which the height of the apparatuses is larger than the horizontal width of at least one of the walls. The need for a heat management system remains paramount despite the shift in design, particularly given the desire for a compact vertical design. The compact vertical design, along with ever increasing performance and feature requirements, creates an interior vertical space that is crowded with heat generating electronic components. As such, there is a need for such a system that can appropriately spread, dissipate and/or expel heat and yet not interfere with the interior electrical components and additionally minimize impact to, or even enhance, mechanical assembly and structural integrity. In many cases, there is a further need for the heat management system to minimize any requirement that increases the interior volume of the device. 
     SUMMARY 
     These and other drawbacks and disadvantages presented by vertically oriented devices are addressed by the principles of the present disclosure, which are directed to a heat management mechanism in an electronic device. However, it can be understood by those skilled in the art that the principles of the present disclosure may offer advantages in horizontally oriented devices as well. 
     According to an implementation, an apparatus is described. The apparatus includes an outer casing enclosing a plurality of electronic components included on at least one printed circuit board, the outer casing having an inner surface and outer surface. The apparatus further includes a heat dissipation structure coupled to the at least one printed circuit board, the heat dissipation structure forming an open-ended columnar channel, the open-ended columnar channel allowing air to flow within the heat dissipation structure in a direction parallel to the at least one printed circuit board. 
     According to an implementation, a heat management device is described. The heat management device includes a heat dissipation structure thermally coupled to a heat generating electronic structure, the heat dissipation structure forming an open-ended columnar channel, the open-ended columnar channel allowing air to flow within the heat dissipation structure in a direction parallel to a planar surface of the heat generating electronic structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The principles of the present disclosure may be better understood in accordance with the following exemplary figures, in which: 
         FIG. 1  is a side view of a vertically oriented electronic device to which the principles of the present disclosure are applicable; 
         FIG. 2  is a first perspective view of a vertically oriented electronic device to which the principles of the present disclosure are applicable; 
         FIG. 3  is a second perspective view of a vertically oriented electronic device to which the principles of the present disclosure are applicable; 
         FIG. 4  is a third perspective view of a vertically oriented electronic device to which the principles of the present disclosure are applicable; 
         FIG. 5  is a cross-sectional view of an electronic device, taken along line  5 - 5  in  FIG. 1  to which the principles of the present disclosure are applicable; 
         FIG. 6 a    is an exemplary heat sink or heat spreader used in an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 6 b    is another exemplary heat sink or heat spreader used in an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 6 c    is a further exemplary heat sink or heat spreader used in an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 7 a    is an exemplary heat sink or heat spreader including an electronic component interface feature used in an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 7 b    is an exemplary spacer used with a heat sink or heat spreader used in an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 8 a    is a perspective view of an electronic device illustrating the internal components including a baffle element to which the principles of the present disclosure are applicable; 
         FIG. 8 b    is a cross-sectional view of an electronic device, taken along line  8 - 8  in  FIG. 8 a   , illustrating a baffle element to which the principles of the present disclosure are applicable; 
         FIG. 9  is a cross-sectional view of an electronic device, taken along line  9 - 9  in  FIG. 1 , showing air flow through the electronic device to which the principles of the present disclosure are applicable; 
         FIG. 10  is a cross-sectional view of another exemplary internal structure contained within the case of an electronic device, taken along line  5 - 5  in  FIG. 1 , to which the principles of the present disclosure are applicable; 
         FIG. 11 a    is an exemplary attachment ring for an internal structure contained within the case of an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 11 b    is an exemplary mechanical assembly including an attachment ring and internal structure for mounting in a case of an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 12  is an exemplary baffle structure for mounting in a case of an electronic device to which the principles of the present disclosure are applicable; 
         FIG. 13  is an exploded view of a set of exemplary components used as part of assembling an electronic device to which the principles of the present disclosure are applicable. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure may also be applicable to electronic apparatuses or devices in the field described as being typically assembled apparatuses having a plurality of walls and a heat management system or mechanism including one or more heatsinks. The present disclosure also addresses how the heat management system or mechanism including one or more heatsinks may be incorporated into an assembly process for the electronic apparatuses and devices. 
     The present description illustrates the principles of the present disclosure. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the present disclosure and are included within the scope of the claims. 
     All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the principles of the present disclosure and the concepts contributed by the inventor(s) to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. 
     Moreover, all statements herein reciting principles, aspects, and embodiments of the principles of the present disclosure, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. 
     Turning to  FIGS. 1-4 , several views of an exemplary device  100  including a heat management mechanism according to aspects of the present disclosure are shown. Electronic device  100  is primarily oriented in a vertical arrangement. It is important to note that although electronic device  100  is shown have a particular shape, electronic device  100  may take on a shape other than that shown without deviating from the principles of the present disclosure. Because vertically oriented electronic devices appear to be of interest in the consumer market, some focus of the current principles, such as the principles of the heat management mechanism described herein, are applied to vertically oriented electronic devices but these principles may also be applied to electronic devices arranged in a more horizontal orientation. The same reference numbers will be maintained throughout the description of  FIGS. 1-4 . 
       FIG. 1  shows a side view of an exemplary electronic device  100 . The electronic device  100  includes an upper case  110 , a lower case  120 , and a base  130 . The upper case  110  and lower case  120  may be assembled using any one of several mechanical coupling mechanisms. In one embodiment, the upper case  110  and lower case  120  may be mechanically coupled using a combination hook and latch mechanism. The hook and latch mechanism includes one or more hook mechanisms located on at or near the mating edge of the interior surface of one of the faces or vertical planes of both upper case  110  and lower case  120 . The hook and latch mechanism also includes one or more latch mechanisms located at or near the mating edge of the interior surface of one of the faces or vertical planes opposite the location of the hook mechanisms on both upper case  110  and lower case  120 . The hook and latch mechanism may be created in plastic as part of the plastic molding process while creating upper case  110  and lower case  120 . An additional mechanical coupling mechanism is used for assembly of base  130  to the bottom section of lower case  120  including, but not limited to, the combination hook and latch mechanism described above. 
       FIG. 2  shows a first perspective view of the exemplary electronic device  100 . An upper vent mechanism  140  is shown included in the top surface of upper case  110 . Upper vent mechanism  140  may include a plurality of parallel ribs forming a grid that has open space between them. The open space allows air to flow from inside electronic device  100  outwardly between the ribs. Other shapes may be used to form the vent mechanism  140 . It is important to note that in some embodiments, the upper vent mechanism  140  may be included near the top section of one or more faces of upper case  110 . In such an instance, it is advantageous that upper vent mechanism  140  be located in a position that is above any heat generation components included inside electronic device  100 . 
       FIG. 3  shows a second perspective view of the exemplary electronic device  100 . A lower vent mechanism  150  is shown included in the bottom surface of lower case  120 . Lower vent mechanism  150  is similar in appearance to upper vent mechanism  140 , allowing air to flow inwardly from the exterior to the interior of electronic device  100 . Lower vent mechanism, along with upper vent mechanism  140  described in  FIG. 2 , used to form a portion of the heat management system of electronic device  100 . In some embodiments, lower vent mechanism  150  may be part of base  130  and used to form the bottom face of lower case  120  when assembled. It is important to note that in some embodiments, the lower vent mechanism  150  may be included near the bottom section of one or more faces of lower case  120 . In such an instance, it is advantageous that the lower vent mechanism  150  be located in a position that is below any heat generation components included inside electronic device  100 . 
       FIG. 4  shows a third perspective view of the exemplary electronic device  100 . An electrical interface panel  160  is shown included on a face of lower case  120 . In some embodiments, electrical interface panel  160  is located on the back face of electronic device  100 . Electrical interface panel  160  may include connectors, switches, and buttons associated with the operation of electronic device  100 . In some embodiments, the connectors, switches, and buttons may be mounted on a printed circuit board included as part of the electronics housed in electronic device  100  and may protrude and/or be accessible through one or more openings in lower case  120 . 
     It should be understood that electronic device  100  contains a plurality of electronic components for proper operation. The electronic components may include but are not limited to a printed circuit board (PCB), a hard drive, a smart card assembly, a tuner, and an antenna, an integrated circuit, and the like. 
     Also, it is intended that expressions such as “back” and “front” and “vertical” and “horizontal,” as well as other complementary terms are intended to be construed from the perspective of the observer of the figures; and as such, these expressions can be interchanged depending upon the direction from which the device is observed. 
       FIG. 5  shows a cross-sectional view  500  of an electronic device, such as electronic device  100  described in  FIGS. 1-4 , taken along line  5 - 5  in  FIG. 1  according to aspects of the present embodiments. Cross sectional view  500  illustrates an exemplary internal structure contained within the case and the interface between the electronics and the heat management mechanism included in the electronic device  100 . Case  505  may include a plurality of elements (e.g., upper case  110  and lower case  120  described in  FIGS. 1-4 ) and may be made or formed from an appropriate aesthetic material, such as plastic. A first PCB  510  may include a plurality of electronic components mounted on one or both surfaces and electrically connected to a plurality of conducting traces on the surface or within layers of PCB  510 . A shield structure  515  may be mounted perpendicular to one surface of PCB  510  and be electrically connected to one or more of the plurality of conducting traces on the one surface. Shield structure  515  may be formed as a frame and may surround all or a portion of the components mounted on a surface of PCB  510 . Shield structure  515  may also include a lid (not shown) that is mechanically mounted to the frame of shield structure  515 . 
     A second PCB  525  may also include a plurality of electronic components mounted on one or both surfaces and electrically connected to a plurality of conducting traces on the surface or within layers of PCB  525 . A shield structure  535  may be mounted to a first surface of PCB  525  and electrically connected to one or more of the plurality of conducting traces on the first surface. An additional shield structure  540  may be mounted to a second surface of PCB  525  and electrically connected to one or more of the plurality of conducting traces on the second surface. The form and characteristics of shield structure  535  and shield structure  540  are similar to shield structure  515 . One or more electrical interface components  530 , such as connectors, switches, and buttons, may be mounted to and one surface of PCB  525  and electrically connected to a plurality of conducting traces on the surface or within layers of PCB  525 . The one or more electrical connectors  530  may be positioned on PCB  525  such that may protrude through at least one opening in case  505  in a manner similar to electrical interface panel  160  described in  FIG. 4 . 
     PCB  510  has a heat spreader  545  coupled to one of its surfaces through a thermal interface  560 . A heat spreader  545  is a type of heat sink providing heat dissipation properties and it is noted that the terms heat spreader and heat sink are often used interchangeably. Heat spreader  545  may have one or more contact areas, through thermal interface  560 , to the surface of PCB  510  or to one or more heat generating electronic components on the surface of PCB  510 . Heat spreader  545  may extend horizontally to span at least the horizontal width of PCB  510 . Heat spreader  545  may also extend vertically to span all or a portion of the vertical height of PCB  510 . Heat spreader  545  has a circumferential shape that is hollow and columnar along the vertical axis of the electronic device and is open at both ends. The opening or shape formed by heat spreader  545  may be referred to as an open-ended columnar channel. A first surface portion  575  of heat spreader  545  extends parallel along the surface to both ends of PCB  510  in a horizontal direction and extends further outward to the inner surface of case  505  of the electronic device. A second surface portion  580  of heat spreader  545  extends or wraps horizontally from one side of case  505  following or extending along the contour of a portion or section of the inner surface of case  505  and terminates at the other side of case  505  joining up to the first surface portion  575  of heat spreader  545  to form the shape around, or encompass, the open-ended columnar channel. An additional portion  585  of heat spreader  545  may be formed as an extension from the open-ended columnar channel formed by the surface portions  575  and  580 . The additional portion  585  may start at the location of the intersection for the first surface portion  575  and the second surface portion  580 . The additional portion  585  of heat spreader  545  is formed to follow or extend along the contour of the inner surface along a different portion of the inner surface of case  505 , such as the opposite side of case  505  from the side to which the second surface portion  580  is located. 
     A second heat spreader  520  is coupled to a second surface of PCB  510  through a thermal interface  565 . Heat spreader  520  may also have one or more contact areas to the surface, one or more electronic components or one or more shields of PCB  510 , as described above. Heat spreader  520  is also formed as an open-end columnar channel, as described for heat spreader  545 . 
     A third heat spreader  550  is coupled to a surface of PCB  525  through a thermal interface  570 . Heat spreader  550  may have one or more contact areas to the surface, to one or more electronic components, or to one or more shields of PCB  525 , as described above. Heat spreader  550  includes a first surface portion  590  and a second surface portion  595  to form a shape around an open-ended columnar channel similar to that described for heat spreader  545 . Heat spreader  550  may extend horizontally to span all or a portion of the horizontal width of PCB  525 . Heat spreader  545  may also extend vertically to span all or a portion of the vertical height of PCB  525 . The first surface portion  590  of heat spreader  545  extends parallel along the surface to one end of PCB  510  in a horizontal direction and extends further outward to the inner surface of case  505  of the electronic device closest to the one end. The first surface portion  590  does not extend to the other end of PCB  510  due to the presence of the one or more electrical interface components  530 . A second surface portion  595  of heat spreader  545  extends or wraps horizontally from one side of case  505  to the other side of case  505  following or extending along the contour of a portion or section of the inner surface of case  505  and joins up to the first surface portion  590  of heat spreader  550  without interfering with the one or more electrical interface components  530 . It is important to note that, in some embodiments, heat spreader  520  and heat spreader  550  may be different in shape from the shape of heat spreader  545  while still maintaining the properties required to form an open-ended columnar channel. 
     Thermal interfaces  560 ,  565 , and  570  may be one or more of several possible interface elements including, but not limited to, heatsink or thermal grease, pyrolytic graphite pads, sil-pads, phase change materials, thermal adhesives, and potting compounds. It is important to note that in some embodiments, one or more of the thermal interfaces  560 ,  565 , and  570  may be used as part of the mounting or support structure for the heatsink to PCB interface or for the internal component structure. 
     As part of the principles of the present disclosure, the arrangement shown in cross-sectional view  500  may be referred to as a two PCB stack heat management mechanism. The arrangement and orientation of heat spreader  545 , heat spreader  520 , and heat spreader  550  with respect to PCB  510  and PCB  525  provides a balance of heat management for the electronic components on PCB  510  and PCB  525  inside case  505 . The arrangement extracts heat from the heat generating electronic components or elements of both PCB  510  and PCB  525  and allows the heat to escape or dissipate through the open-ended columnar channel formed by heat spreaders  545 ,  520 , and  550  by convection air flow from inlet vents located below PCB  510  and PCB  525  to outlet vents located above PCB  510  and  525 . Additionally, the open-end columnar channel shape of heat spreader  545 , heat spreader  520 , and heat spreader  550  provide extraction of heat from PCB  510  and PCB  525  through the interior area of heat spreader  545 , heat spreader  520 , and heat spreader  550  as a result of convection air flow created by inlet and outlet vents include as part of case  505 . In this manner, the open-ended columnar channel shape of heat spreader  545 , heat spreader  520 , and heat spreader  550  functions as a convective chimney. Further, the planar and circumferential shape and span of heat spreader  545  and heat spreader  550  also provide conduction of heat from the surface portion coupled to the PCB  510  and PCB  525  (e.g., first surface portion  575  and first surface portion  590 ) around the circumference of the heat spreader to the surface portion near the inner surface of outer case  505  (e.g., second surface portion  580  and second surface portion  595 ). Further, the opposing orientation of the first surface portions  575 ,  590  and second surface portions  590 ,  595  of heat spreader  545  and heat spreader  550  create a thermal reflection mechanism. For example, heat generated by electronic components of PCB  510  and PCB  525  that is conducted into the first surface portions  575  and  590  and radiated into the interior region of heat spreaders  545  and  550  will be reflected back into the interior region due to the presence of the second surface portions  580  and  595 . The forming of first surface portion  575  and additional surface portion  585  of heat spreader  545  to follow the shape and extend along the inner surface of case  505  additionally provides a uniform surface temperature due to heat radiation from the heat spreaders along a substantial portion of the inner surface of case  505 . The uniform surface temperature results in a decrease or elimination of undesirable hot spots that a user may contact when touching the outer surface of case  505 . It is important to note that these principles may be applied in a variety of shapes and structures that utilize convective chimney principles and an open-ended columnar channel shape. 
     It is important to note that the size of heat spreader  545  is much larger than the size of heat spreader  550  and the size of heat spreader  520 . The difference in size, as well as surface area and shape, is to account for a difference in the amount of heat generated by the electronic components for each of PCB  510  and PCB  525 . In the present embodiment, the heat generated from PCB  510  is greater than the heat generated from PCB  525 . In other embodiments, the heat generated may be equal or may be reversed in magnitude for PCB  510  and PCB  525 . In these embodiments, the size, as well as surface area and shape, of each of the heatsinks may be adjusted according to design techniques for the heat generated as well as the space allocated within case  505  without deviating from the principles of the present disclosure. Further, in some embodiments, heat spreader  520  may additionally be coupled, through a thermal interface, to PCB  525  or may not be present as it is may not be needed as part of the thermal management mechanism. 
     Further, as a result of the difference in the amount of heat generated from PCB  510  being greater than PCB  525 , heat spreader  545  is shown as extended to wrap around the inner surface of case  505  in the region occupied by PCB  525  and heat spreader  550 . The additional surface area for heat spreader  545  allows for additional heat spreading or thermal dissipation from PCB  510  as well as a lower and more uniform surface temperature along the entire outer surface of case  505 . Further, the transfer of heat generated from PCB  510  into the region occupied by PCB  525  and heat spreader  550  also provides better thermal balance between the regions occupied by PCB  525  and PCB  510 . Heat spreader  550  is not coupled or connected (e.g., with a thermal interface material) to heat spreader  545 . 
     Although heat spreader  545 , heat spreader  520 , and heat spreader  550  may be mechanically coupled or attached to PCB  510  and PCB  525  using only the properties of thermal interfaces  560 ,  565 , and  570 , additional attachment mechanisms may be included (not shown). These attachment mechanisms may include, but are not limited to, a screw, push pin, twist pin or screw pin. Further mechanical interfaces may be included on PCB  510  and PCB  525  as well as heat spreaders  545 ,  520 , and  550  to accommodate the attachment mechanisms. In some embodiments, the attachment mechanism may minimize or prevent direct thermal coupling by utilizing a thermally insulated attachment mechanism and/or by eliminating copper surfaces on and through PCBs  510  and  525  under or around the attachment mechanism. 
     In some embodiments, a fan or blower (not shown) may be included and placed either above or below PCB  510  and PCB  525  in order to pull air or push air through the inside of case  505  and through the convection chimneys formed by heat spreader  545 , heat spreader  520 , and heat spreader  550 . The additional air flow may further improve cooling efficiency. The fan may continuously operate or may be controlled by an electronic component and/or a sensor and operate based on a measured condition inside case  505 , such as air temperature. 
       FIGS. 6 a -6 c    illustrate exemplary material and construction aspects for a heat sink or heat spreader, such as heat spreader  545 , heat spreader  520 , or heat spreader  550  described in  FIG. 5 , according to aspects of the present disclosure. The heat sink illustrated in  FIGS. 6 a -6 c    includes a circumferentially shaped element that is used as a convection chimney having the properties and characteristics, as described above.  FIG. 6 a    shows a heat sink  610  constructed or formed using an extrusion or casting process with aluminum or an aluminum compound as the base material. The extrusion or casting process creates a heat sink that does not require any seams. It is important to note that if heat sink  610  is formed using a casting process, zinc or a zinc compound may also be used as the base material. The extrusion or casting process used for heat sink  610  will require a minimum defined thickness in order to avoid extrusion or casting deficiencies. 
       FIG. 6 b    shows a heat sink  620  constructed or formed from sheet aluminum using a cutting, pressing, and bending process. Heat sink  620  is constructed by cutting a planar section from the sheet aluminum that has been dimensioned to result in the desired three-dimensional shape for heat sink  620  when pressed and bent. The cut planar section is bent and pressed using one or more pressing and forming tools. In some embodiments, the closing of the convection chimney aspect of the heat sink may require one or more fastening elements or welding steps. The material properties of aluminum allow heat sink  620  to be made using thinner material than required for heat sink  610  but will still require a minimum defined thickness in order to avoid stress fracturing during the forming process. 
       FIG. 6 c    shows a heat sink  630  constructed or formed from sheet steel using a cutting, pressing, and bending process. Heat sink  630  is constructed by cutting a planar section from the sheet steel that has been dimensioned to result in the desired three-dimensional shape for heat sink  630  when pressed and bent. The cut planar section is bent and pressed using one or more pressing and forming tools. In some embodiments, the closing of the convection chimney aspect of the heat sink may require one or more fastening elements or welding steps. The material properties of sheet steel allows heat sink  630  to be made using thinner material than required for heat sink  620  and heat sink  610  with less risk of stress fracturing during forming. In some embodiments, the sheet steel may be pre-plated or post-plated after forming in any one of the conventional plating manners known to those skilled in the art. It is important to note that heat sinks may be made using other suitable materials and formed using other suitable process as are well known to those skilled in the art. 
       FIG. 7 a    illustrates a heatsink or heat spreader  700 , similar to heat spreader  545 , heat spreader  520 , or heat spreader  550  described in  FIG. 5 , including an electronic component interface feature according to aspects of the present disclosure. Heatsink  700  includes a protrusion element  710  that facilitates surface contacting interface to an electronic component, such as an integrated circuit, a portion of a shield, or an area on the surface of a PCB. In some embodiments, the protrusion element  710  may be formed or pressed as part of heatsink  700 . The forming process may depend on the type of material used and/or the process used for forming the heatsink. For example, if sheet steel is used, as described for heat sink  630  in  FIG. 6 c   , protrusion element  710  may be formed into the sheet steel when the heatsink is formed. In another example, if aluminum is used as part of an extrusion or casting process, a separate spacer may be formed to be used as protrusion element  710  and attached to the heatsink using an adhesive, such as a thermally conductive adhesive. An example spacer  720  that may be used as a protrusion element, such as protrusion element  710 , is shown in  FIG. 7   b.    
       FIGS. 8 a -8 b    illustrate an exemplary electronic device  800 , similar to electronic device  100  described above, incorporating aspects of a heat management system according to the present embodiments.  FIG. 8 a    is a perspective view perspective showing the elements internal to electronic device  800 .  FIG. 8 b    is a cross-sectional view of electronic device  800 , taken along line marked  8 - 8  in  FIG. 8   a.    
     Electronic device  800  includes a baffle element  810  and an internal component stack  820 . Baffle element  810  is located internal to the case of electronic device  800  in a space between the upper surface of the electronic device and the internal component stack  820 . Internal component stack  820  may include one or more PCBs and associated thermal components, such as PCB  510  and PCB  525  and associated heat spreaders described in  FIG. 5 . In one embodiment, baffle element  810  is located at the top plane of, and perpendicular to, internal component stack  820  and spans the distance across the inner surfaces of the electronic device. Baffles element  810  acts as a thermal barrier for air flow management inside of the electronic device. The upward flow of air is controlled through one or more openings or vents  830  in baffle element  810 . The one or more openings or vents  830  may be formed as holes, slots, or any other suitable type of opening. The one or more openings or vents  830  may be positioned in specified or predetermined locations along the planar surface of baffle element  810 . The locations may be chosen based on empirical data gathered as part of design criteria for the electronic device. In some embodiments, the vent openings may be adjustable either during assembly of the electronic device or during operation of the electronic device. 
       FIG. 9  shows a cross-sectional view of an electronic device  900 , similar to electronic device  100  described in  FIGS. 1-4 , taken along a line marked  9 - 9  according to aspects of the present embodiments. The cross sectional view of electronic device  900  provides a representation of the air flow control associated with the heat management system according to aspects of the present disclosure. Air flow lines  910  illustrate a flow of air upward through electronic device  900 . External air enters through vents in the bottom of electronic device  900  (e.g., through lower vent mechanism  150  described above), flowing through the internal component stack and across the heatsinks, passing through, in an intentionally controlled manner, openings in a baffle, such as baffle element  810  described in  FIG. 8 . The air flow that passes through the openings in the baffle further flows out of the top of electronic device  900  (e.g., through upper vent mechanism  140  described above). The baffle provides an air flow restriction to control the rate of air flow through electronic device  900  and maintains a certain volume of air in the space occupied by the internal component stack in electronic device  900  as part of the heat management system. 
       FIG. 10  is a cross-sectional view of an electronic device  1000 , similar to electronic device  100  described in  FIGS. 1-4 , taken along line  5 - 5  in  FIG. 1  according to aspects of the present disclosure. Cross-sectional view  1000  illustrates another exemplary internal structure contained within the case and the interface between the electronics and the heat management mechanism included in electronic device  1000 . Case  1005  may include a plurality of elements (e.g., an upper case  110  and a lower case  120  as described above) and may be made or formed from an appropriate aesthetic material, such as plastic. A PCB  1010  may include a plurality of electronic components mounted on one or both surfaces and electrically connected to a plurality of conducting traces on the surface or within layers, as described above in  FIG. 5 . A shield structure (not shown) may be mounted to one or both surfaces of PCB  1010  and formed as well as electrically connected to one or more of the plurality of conducting traces on the surfaces of PCB  1010 , as described above. 
     A first heat sink  1045  is coupled to a first one of the surfaces of PCB  1010 . Heat sink  1045  may have one or more contact areas, through thermal interfaces (not shown), to the surface of PCB  1010 , to metal shields (not shown) mounted to the surface of PCB  1010 , or to one or more heat generating electronic components (not shown) on the surface of PCB  1010 , as described above. Heat sink  1045  has a circumferential shape to form an open-ended columnar channel similar to heat spreader  545  described in  FIG. 5 . The outer portion of heat sink  1045 , away from PCB  1010 , extends around following or extending along the contour of the inner surface of case  1005 , as described above. 
     A second heat sink  1050  is coupled to a second surface of PCB  1010 . Heat sink  1050  may have one or more contact areas, through thermal interfaces (not shown), to the surface, one or more electronic components, or one or more shields (not shown) mounted on PCB  1010 , as described above. Heat sink  1050  also has a circumferential shape forming an open-ended columnar channel, as described above for heat spreader  550 . As with heat sink  1045 , the outer portion, away from PCB  1010 , wraps around following the contour of the inner surface of case  1005 , as described above. In cross-section  1000 , heat sink  1045  is thermally coupled to electronic components, shields, or the surface of one side of PCB  1010  while heat sink  150  is thermally coupled to the electronic components, shields, or the surface of another or second side of PCB  1010 . Further, the outer portion of heat sink  1050  extends along the contour of the inner surface on an opposite inner surface of case  1005  from the outer portion of heat sink  1045 . In some embodiments, heat sink  1045  and heat sink  1050  may have some overlap and further may be directly thermally coupled. It is important to note that heat sink  1045  and heat sink  1050  are shown as formed from sheet steel and include seam sections  1055 . In some embodiments, other materials and other formation processes may be used, as described above. 
     An attachment interface  1095  is shown to mechanically couple heat sink  1045  and heat sink  1050  to PCB  1010 . In some embodiments, more than one attachment interface  1095  may be included. Further, in some embodiments, the mechanical coupling of attachment interface  1095  may not provide direct thermal coupling, by utilizing a thermally insulated attachment mechanism (e.g., an insulated screw, push pin, twist pin or screw pin) and by eliminating copper surfaces on and through PCB  1010  under attachment interface  1095 . 
     As part of the principles of the present disclosure, the arrangement shown in  FIG. 10  may be referred to as a single PCB stack heat management mechanism. The arrangement and orientation of heat sink  1045  and heat sink  1050  with respect to PCB  1010  provides balanced heat management. The arrangement extracts heat from the electronic components on both sides of PCB  1010  and allows the heat to escape or dissipate through the open-ended columnar channel formed by heat sinks  1045  and  1050  by convection air flow from inlet vents located below PCB  1010  to outlet vents located above PCB  1010 , as described above. Further, the planar and circumferential shape and span of heat sink  1045  and heat sink  1050  also provide conduction of heat from the electronic components, shields, and surfaces of both sides of PCB  1010  circumferentially around the surface to the portions of heat sinks  1045  and  1050  near the inner surface of outer case  1005 , as described above. Further, the open-ended columnar channel shape creates a thermal reflection mechanism into the interior region of heat sinks  1045  and  1050 , as described above. The forming of the outer portions of heat sinks  1045  and  1050  to extend along the shape and contours of the inner surface of case  1005  additionally provides uniform heat radiation along a substantial portion of the inner surface of case  1005  to prevent undesirable hot spots that a user may contact when touching the outer surface of case  1005 , as described above. 
     It is important to note that the size, in terms of surface area as well as area encompassed by the structure of heat spreader  1050  is larger than the size of heat spreader  1045 . The difference in size may be based on empirical data indicating that the heat generated from the lower surface of PCB  1010 , interfaced to heat sink  1050 , is greater than the heat generated by the upper surface of PCB  1010 . In other embodiments, the heat generated may be more equal or may be reversed in magnitude for the two PCBs. In these embodiments, the size, as well as surface area and shape, of each of the heatsinks may be adjusted accordingly without deviating from the principles of the present disclosure. In other embodiments, heat spreader  1050  may include a portion that extends or wraps further around the inner surface of case  1005  overlapping but not thermally contacting heat sink  1045  in a manner similar to that described in  FIG. 5 . 
     It is important to note that the principles of the present embodiments relating to heat management may be applied to other devices that include electronic circuits that may be classified as heat generating structures or elements, particularly to other devices that are vertically oriented. Such devices may include, but are not limited to, hard disk drives such disk drive arrays, optical drives, processor-based server racks, and the like. For example, a first heat sink, similar to heat sink  1045 , or heat spreader  545  described in  FIG. 5 , may be thermally coupled to a first planar surface of the heat generating structure in the device. A second heat sink, similar to heat sink  1050 , or heat spreader  550  described in  FIG. 5 , may be thermally coupled to a second planar surface of the heat generating structure in the device. The outer portions of the two heat sinks may follow or extend along the contour of the inner surface of the enclosure or case surrounding the heat generating structure and/or forming the outside surface of the device. Other possible configurations for heat management mechanisms in similar devices as described in the present embodiments, including those described in  FIG. 5 , may also be used. 
     In some embodiments, a fan or blower (not shown) may be included and placed either at the top of case  1005  above PCB  1010  or at the bottom of case  1005  below PCB  1010 . The fan may pull air or push air through the inside of case  1005  and through the convection chimneys in heat spreader  1045  and heat spreader  1050  to improve cooling efficiency. The fan may continuously operate or may be controlled by an electronic component and/or a sensor and operate based on a measured condition inside case  1005 , such as air temperature. 
       FIG. 11 a    illustrates an exemplary attachment or mounting ring  1110  used in conjunction with a mechanical assembly as part of an electronic device, such as electronic device  100  described earlier, according to aspects of the present disclosure. Mounting ring  1110  is used as a mounting bracket for the internal component stack, such as the two PCB stack heat management mechanism described in  FIG. 5  or the single PCB stack heat management mechanism described in  FIG. 10 . Attachment or mounting ring  1110  includes mounting holes  1120  for attaching the mounting ring to the internal component stack. Mounting ring  1100  also includes upper retainer clip  1130  and lower retainer clip  1140  for securing amounting ring  1110  to the case (e.g., upper case  110  and lower case  120  described earlier) of the electronic device. It is important to note that mounting ring  1110  may be a complete or closed ring or may include a gap or space along its circumference, referred to as an open ring. 
       FIG. 11 b    illustrates a mechanical assembly  1100  used as part of an electronic device, such as electronic device  100  described earlier, according to the principles of the present disclosure. Mechanical assembly  1100  includes mounting ring  1110 , as described in  FIG. 11 a   , attached to internal component stack  1115 . Internal component stack  1115  also includes electrical interface panel  1150  similar to the interface panels described above positioned to span the gap in the circumference of mounting ring  1110 . Internal component stack  1115  is illustrated as a one PCB stack heat management mechanism including internal mounting element  1160 . In other embodiments, different component stacks, such as the two PCB stack heat management mechanism described above, may be used. Mounting ring  1110  is attached to internal component stack  1115  using a fastener through mounting hole  1120 . The fastener may be any suitable type of attachment component including, but not limited to, a screw, a bolt, a rivet, and a push pin. 
       FIG. 12  show another exemplary baffle structure  1200  as part of an electronic device, such as electronic device  100  described above, according to the principles of the present disclosure. Baffle structure  1200  includes an outer ring  1210  for coupling and/or attaching to the case of the electronic device in a manner similar to attachment or mounting ring  1110  described above. Baffle structure  1200  also includes a baffle plate  1220  located perpendicular to and internal in the space within outer ring  1210 . Baffle structure  1200  may be located in a planar position in the case of the electronic device above the internal component structure or PCB stack in a manner similar to the baffle element  810  described above. Baffle structure  1200  also includes one or more openings or vents  1230  on baffle plate  1220  to control airflow in a manner similar to that described above. The locations for the openings or vents  1230  may be chosen based on empirical data gathered as part of design criteria for the electronic device. In some embodiments, the vent openings may be adjustable either during assembly of the electronic device or during operation of the electronic device. Mounting ring  1210  may also include one or more retainer mechanisms (not shown) for attaching to one or more portions of the case of the electronic device. 
       FIG. 13  shows an exemplary exploded view of the assembly components for an electronic device  1300 , similar to electronic device  100  described above, according to aspects of the present disclosure. An upper vent  1310 , similar to upper vent mechanism  140  described in  FIG. 2 , mounts or is attached to case extension  1320 . A baffle structure  1330 , similar to baffle structure  1200  described in  FIG. 12 , mounts or is attached between case extension  1320  and upper case  1340 , which is similar to upper case  110  described in  FIG. 1 . Heat sink or heat spreader  1350  and heat sink or heat spreader  1360  mount to or are attached to PCB  1355  in a manner similar to the single PCB heat management mechanism described in  FIG. 10 . A retainer ring  1365 , which is similar to mounting ring  1110  described in  FIG. 11 a   , attaches to the assembly formed by heat sink or heat spreader  1350 , heat sink or heat spreader  1360 , and PCB  1355  to form a mechanical assembly similar to mechanical assembly  1100  described in  FIG. 11 b   . The mechanical assembly is affixed in a position internal to and within upper case  1340  and lower case  1370  using mounting or attachment ring  1365  between upper case  1340  and lower case  1370 . Lower case  1370  is similar to lower case  120  described in  FIG. 1 . A base  1380 , which is similar to base  130  described in  FIG. 1 , mounts or is attached to lower case  1370 . Either one or bother of lower case  1370  and base  1380  may include one or more vent openings similar to lower vent mechanism  150  described in  FIG. 3 . 
     One or more embodiments of the present disclosure provide a heat management mechanism for an electronic device. The heat management mechanism includes a heat dissipation structure that is particularly suited for vertically oriented electronic devices. The heat dissipation structure includes one or more heat sinks, or heat spreaders, coupled to electronic components mounted on printed circuit boards or to other heat generating electronic elements or structures. The heat sinks, or heat spreaders, form open-ended columnar channels that allow air to pass through the open inner regions of the heat sinks or heat spreaders. The heat sinks or heat spreaders operate as convective chimneys by allowing air flow upward from the bottom of the case of the electronic device below the heat generating electronic element or structure, such as electronic components on a printed circuit board, through to the top of the of the case. The arrangement and construction of the printed circuit boards or other heat generating electronic structures and the heat sinks or heat spreaders additionally provide an efficient assembly mechanism by simply stacking a set of coupled components that support and provide stability for the printed circuit board and heat sink or heat spreader assembly within the case of the electronic device. 
     According to the present disclosure, an apparatus is described that includes an outer casing enclosing a plurality of electronic components included on at least one printed circuit board, the outer casing having an inner surface and an outer surface. The apparatus further includes a heat dissipation structure coupled to the at least one printed circuit board, the heat dissipation structure forming an open-ended columnar channel, the open-ended columnar channel allowing air to flow within the heat dissipation structure in a direction parallel to the at least one printed circuit board. 
     In some embodiments, the heat dissipation structure includes a first heat spreader, the first heat spreader having a first portion extending in a direction parallel to a portion of the at least one printed circuit board and being thermally coupled to one of the plurality of electronic components mounted on the portion of the at least one printed circuit board, the first heat spreader also having a second portion extending along a contour of a first portion of the inner surface of the outer casing and opposite the first portion, the first portion and second portion forming the open-ended columnar channel. 
     In some embodiments, the heat dissipation structure further includes a second heat spreader, the second heat spreader having a first portion extending in a direction parallel to at least a different portion of the at least one printed circuit board and being thermally coupled to one of the plurality of electronic components mounted on the different portion of the at least one printed circuit board, the second heat spreader also having a second portion extending along a contour of a second portion of the inner surface of the outer casing and opposite the first portion of the additional open-ended columnar channel, the second portion of the inner surface being different from the first portion of the inner surface, the first portion and the second portion of the second heat spreader forming an additional open-ended columnar channel. 
     In some embodiments, the first heat spreader includes an additional portion mechanically coupled to at least one of the first portion and the second portion of the first heat spreader, the additional portion further extending along a contour of the second portion of the inner surface of the outer casing. 
     In some embodiments, the at least one printed circuit board is two circuit boards and wherein the first heat spreader dissipates heat generated by electronic components on a first printed circuit board and the second heat spreader dissipates heat generated by electronic components on a second printed circuit board. 
     In some embodiments, the first heat spreader and the second heat spreader are not thermally coupled to each other. 
     In some embodiments, the second portion of the first heat spreader extends along the contour of the portion of the inner surface to maintain even temperature of the outer surface of the outer casing. 
     In some embodiments, the apparatus further includes a baffle element enclosed by the outer casing and perpendicular to an opening in the heat dissipation structure, the baffle element located beyond one end of the printed circuit board, the baffle element including at least one opening for control of airflow through the heat dissipation structure. 
     In some embodiments, the outer casing further includes a first vent structure located beyond a first end of the printed circuit and a second vent structure located beyond a second end of the printed circuit board. 
     In some embodiments, the at least one printed circuit board is vertically oriented and is parallel to the inner surface of the outer casing. 
     In some embodiments, the apparatus further includes a mounting ring that is mechanically attached to the heat dissipation structure, the mounting ring mounting between a first portion of the outer casing and a second portion of the outer casing, the mounting ring providing secure positioning of the heat dissipation structure within the outer casing. 
     In some embodiments, the heat dissipation structure is formed as part of a casting process using zinc or aluminum or as part of a sheet bending process using aluminum or steel. 
     According to the present disclosure, a heat management device includes a heat dissipation structure thermally coupled to a heat generating electronic structure, the heat dissipation structure forming an open-ended columnar channel, the open-ended columnar channel allowing air to flow within the heat dissipation structure in a direction parallel to a planar surface of the heat generating electronic structure. 
     In some embodiments, the open-ended columnar channel includes a first portion extending in a direction parallel to the at least a portion of the at least one printed circuit board and being thermally coupled to one or more of a plurality of electronic components mounted on the portion of the at least one printed circuit board, and wherein the open-end columnar channel further includes a second portion extending along a contour of a first portion of the inner surface of an enclosure and opposite the first portion. 
     In some embodiments, the heat dissipation structure includes a first heat spreader, the first heat spreader having a first portion extending in a direction parallel to the planar surface of the heat generating structure and being thermally coupled to at least a portion of the planar surface of the heat generating structure, the first heat spreader also having a second portion extending along a contour of a first portion of the inner surface of an enclosure for the heat management device and opposite the first portion, the first portion and second portion forming the open-ended columnar channel. 
     In some embodiments, the heat dissipation structure further includes a second heat spreader, the second heat spreader having a first portion extending in a direction parallel to a different planar surface of the heat generating structure and being thermally coupled to at least a portion of the different planar surface of the heat generating structure, the second heat spreader also having a second portion extending along a contour of a second portion of the inner surface of the enclosure and opposite the first portion of the additional open-ended columnar channel, the second portion of the inner surface being different from the first portion of the inner surface, the first portion and the second portion of the second heat spreader forming an additional open-ended columnar channel. 
     In some embodiments, the first heat spreader includes an additional portion mechanically coupled to at least one of the first portion and the second portion of the first heat spreader, the additional portion further extending along a contour of the second portion of the inner surface of the enclosure. 
     In some embodiments, the heat generating structure is a printed circuit board and wherein the first heat spreader dissipates heat generated by electronic components on a first surface of the printed circuit board and the second heat spreader dissipates heat generated by electronic components on a second surface of the printed circuit board. 
     In some embodiments, the first heat spreader and the second heat spreader are not thermally coupled to each other. 
     In some embodiments, the heat management device further includes a mounting ring that is mechanically attached to the heat dissipation structure, the mounting ring providing secure positioning of the heat dissipation structure within the enclosure for the heat management device. 
     It is important to note that the embodiments described herein are not necessarily intended to include mutually exclusive features or aspects of the principles of the present disclosure. Unless as otherwise indicated, any embodiments described herein or contemplated as a result of using the principles of the present disclosure may include any combination of the features described in any of the above embodiments. 
     Although embodiments which incorporate the teachings of the present disclosure have been shown and described in detail herein, those skilled in the art can readily devise many other varied embodiments that still incorporate these teachings. Having described preferred embodiments of an apparatus for heat management in an electronic device (which are intended to be illustrative and not limiting), it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is, therefore, to be understood that changes may be made in the particular embodiments of the disclosure disclosed which are within the scope of the disclosure as outlined by the appended claims.