PATENT DOCUMENT

Publication Number: US-9282656-B2
Application Number: US-201213719022-A
Country: US
Kind Code: B2

Title: Gaskets for thermal ducting around heat pipes

Abstract:
The disclosed embodiments provide a component for a portable electronic device. The component includes a gasket containing a rigid portion disposed around a bottom of a heat pipe, wherein the rigid portion forms a duct between a fan and an exhaust vent of the electronic device. The gasket also includes a first flexible portion bonded to the rigid portion, wherein the first flexible portion comprises a flap that is open during assembly of the heat pipe in the electronic device and closed over the heat pipe and the rigid portion to seal the duct around the heat pipe after the assembly.

Claims:
What is claimed is: 
     
       1. A component in an electronic device, comprising a gasket, wherein the gasket includes:
 a rigid portion disposed around a bottom of a heat pipe, wherein the rigid portion forms a duct between a fan and an exhaust vent of the electronic device; and 
 a first flexible portion bonded to the rigid portion, wherein the first flexible portion comprises a flap that is open during assembly of the heat pipe in the electronic device and closed over the heat pipe and the rigid portion to seal the duct around the heat pipe after the assembly. 
 
     
     
       2. The component of  claim 1 , wherein the gasket further comprises a second flexible portion bonded to one or more edges of the rigid portion, wherein the second flexible portion contacts the first flexible portion and the heat pipe to further seal the duct around the heat pipe. 
     
     
       3. The component of  claim 2 , wherein the first and second flexible portions further seal the duct around at least one of:
 the fan; 
 a bottom enclosure of the electronic device; 
 a top enclosure of the electronic device; and 
 the exhaust vent. 
 
     
     
       4. The component of  claim 2 , wherein the first and second flexible portions are bonded to the rigid portion using an overmolding technique. 
     
     
       5. The component of  claim 2 , wherein the first and second flexible portions form a compression seal around the heat pipe. 
     
     
       6. The component of  claim 1 , wherein the rigid portion comprises plastic. 
     
     
       7. The component of  claim 1 , wherein the first flexible portion comprises a rubber. 
     
     
       8. The component of  claim 1 , wherein the gasket is separate from the fan. 
     
     
       9. The component of  claim 1 , wherein the flap is open at a first configuration of the component and closed at a second configuration of the component. 
     
     
       10. The component of  claim 1 , wherein the flap rotates from being open to being closed. 
     
     
       11. The component of  claim 1 , wherein the gasket prevents exhaust from the fan from recirculating within the electronic device. 
     
     
       12. A method for assembling an electronic device, comprising:
 placing a gasket within an enclosure of the electronic device, wherein the gasket comprises: 
 a rigid portion, wherein the rigid portion forms a duct between a fan and an exhaust vent of the electronic device; 
 a first flexible portion bonded to the rigid portion, wherein the first flexible portion comprises a flap that is open during assembly of the electronic device; and 
 a second flexible portion bonded to one or more edges of the rigid portion; 
 disposing a heat pipe over the rigid portion and the second flexible portion while the flap is open, wherein the rigid portion is disposed around a bottom of the heat pipe; and 
 closing the flap over the heat pipe, the rigid portion, and the second flexible portion to seal the duct around the heat pipe. 
 
     
     
       13. The method of  claim 12 , wherein the first and second flexible portions further seal the duct around at least one of:
 the fan; 
 a bottom enclosure of the electronic device; 
 a top enclosure of the electronic device; and 
 the exhaust vent. 
 
     
     
       14. The method of  claim 12 , wherein the first and second flexible portions are bonded to the rigid portion using an overmolding technique. 
     
     
       15. The method of  claim 12  wherein the first and second flexible portions form a compression seal around the heat pipe. 
     
     
       16. The method of  claim 12 , wherein the rigid portion comprises plastic. 
     
     
       17. The method of  claim 12 , wherein the first and second flexible portions comprise a rubber. 
     
     
       18. An electronic device, comprising:
 a heat-generating component; 
 a heat pipe configured to conduct heat away from the heat-generating component; 
 a fan configured to transfer heat from the heat pipe out of the electronic device; and 
 a gasket, comprising: 
 a rigid portion disposed around a bottom of the heat pipe, wherein the rigid portion forms a duct between the fan and an exhaust vent of the electronic device; and 
 a first flexible portion bonded to the rigid portion, wherein the first flexible portion comprises a flap that is open during assembly of the heat pipe in the electronic device and closed over the heat pipe and the rigid portion to seal the duct around the heat pipe after the assembly. 
 
     
     
       19. The electronic device of  claim 18 , wherein the gasket further comprises a second flexible portion bonded to one or more edges of the rigid portion, wherein the second flexible portion contacts the first flexible portion and the heat pipe to further seal the duct around the heat pipe. 
     
     
       20. The electronic device of  claim 19 , wherein the first and second flexible portions further seal the duct around at least one of:
 the fan; 
 a bottom enclosure of the electronic device; 
 a top enclosure of the electronic device; and 
 the exhaust vent. 
 
     
     
       21. The electronic device of  claim 19 , wherein the first and second flexible portions are bonded to the rigid portion using an overmolding technique. 
     
     
       22. The electronic device of  claim 19 , wherein the first and second flexible portions form a compression seal around the heat pipe. 
     
     
       23. The electronic device of  claim 18 , wherein the rigid portion comprises plastic. 
     
     
       24. The electronic device of  claim 18 , wherein the first flexible portion comprises a rubber. 
     
     
       25. The electronic device of  claim 18 , wherein the electronic device is a laptop computer. 
     
     
       26. The electronic device of  claim 18 , wherein the gasket is separate from the fan. 
     
     
       27. The electronic device of  claim 18 , wherein the flap is open at a first configuration of the component and closed at a second configuration of the component. 
     
     
       28. The electronics device of  claim 18 , wherein the flap rotates from being open to being closed. 
     
     
       29. The electronic device of  claim 18 , wherein the gasket prevents exhaust from the fan from recirculating within the electronic device.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority under 35 U.S.C. §119(e) to: U.S. Provisional Application Ser. No. 61/657,532, entitled “Gaskets for Thermal Ducting Around Heat Pipes in Electronic Devices,” by Brett W. Degner, William F. Leggett and Jay S. Nigen, filed on Jun. 8, 2012; and U.S. Provisional Application Ser. No. 61/657,454, entitled “Heat Pipe with Reduced Height,” by Frank F. Liang, and Richard H. Tan, filed on Jun. 8, 2012, the contents of each of which are herein incorporated by reference. 
     This application is also related to: U.S. Provisional Application Ser. No. 61/657,534, entitled “Fasteners for Creating Thermal Gaps in Electronic Devices,” by Brett W. Degner, Charles A. Schwalbach and William F. Leggett, filed on Jun. 8, 2012; U.S. Provisional Application Ser. No. 61/657,505, entitled “Optimized Vent Walls in Electronic Devices,” by Brett W. Degner, Bart Andre, Jeremy D. Bataillou, Jay S. Nigen, Christian A. Ligtenberg, Ron A. Hopkinson, Charles A. Schwalbach, Matthew P. Casebolt, Nicholas A. Rundle and Frank F. Liang, filed on Jun. 8, 2012; and U.S. Provisional Application Ser. No. 61/657,538, entitled “Dual-Thickness Thermal Stages in Electronic Devices,” by Brett W. Degner, Patrick Kessler, Charles A. Schwalbach and Richard H. Tan, filed on Jun. 8, 2012, the contents of all of which are herein incorporated by reference. 
    
    
     BACKGROUND 
     1. Field 
     The disclosed embodiments relate to techniques for facilitating heat transfer in portable electronic devices. 
     2. Related Art 
     A modern portable electronic device typically contains a set of tightly packed components. For example, a laptop computer may include a keyboard, display, speakers, touchpad, battery, buttons, processor, memory, internal storage, and/or ports in an enclosure that is less than one inch thick, 8-11 inches long, and 12-16 inches wide. Moreover, most components in the portable electronic device generate heat, which must be dissipated to enable safe use of the portable electronic device and improve long-term reliability. For example, heat generated by components in a laptop computer may be transferred away from the components and out of the laptop computer to prevent damage to the components and increase user comfort and safety while operating the laptop computer. 
     However, heat-dissipation mechanisms for portable electronic devices generally involve the use of additional parts and/or materials. For example, heat sinks, cooling fans, heat pipes, thermal spreaders, and/or vents may be used to dissipate heat from components in a laptop computer. Such heat-dissipating parts and/or materials may take up space within the portable electronic devices and may add to the cost of the portable electronic devices. 
     Hence, space-efficient designs for portable electronic devices may be facilitated by more efficient and/or smaller heat-dissipation mechanisms in the portable electronic devices. 
     SUMMARY 
     The described embodiments include a component for use in a portable electronic device. The component includes a gasket containing a rigid portion disposed around a bottom of a heat pipe, wherein the rigid portion forms a duct between a fan and an exhaust vent of the electronic device. The gasket also includes a first flexible portion bonded to the rigid portion, wherein the first flexible portion comprises a flap that is open during assembly of the heat pipe in the electronic device and closed over the heat pipe and the rigid portion to seal the duct around the heat pipe after the assembly. 
     In some embodiments, the gasket also includes a second flexible portion bonded to one or more edges of the rigid portion, wherein the second flexible portion contacts the first flexible portion and the heat pipe to further seal the duct around the heat pipe. 
     In some embodiments, the first and second flexible portions further seal the duct around at least one of the fan, a bottom enclosure of the electronic device, a top enclosure of the electronic device, and the exhaust vent. 
     In some embodiments, the first and second flexible portions are bonded to the rigid portion using an overmolding technique. 
     In some embodiments, the first and second flexible portions form a compression seal around the heat pipe. 
     In some embodiments, the rigid portion includes plastic. 
     In some embodiments, the first flexible portion includes a rubber. 
     Another embodiment provides a heat pipe that facilitates heat transfer. The heat pipe includes a sealed housing having an outer surface, an inner surface, two ends and a height less than a predetermined value, where the sealed housing includes a wicking material along at least at least a portion of the inner surface and vapor cavities, and the sealed cavity includes a thermal transport material in a liquid state. Moreover, the heat pipe includes heat exchangers (such as convective-cooling fins), thermally coupled to the sealed housing, at condenser regions of the sealed housing proximate to the ends of the sealed housing. During operation of the heat pipe, the sealed housing supports a two-phase bidirectional flow of the thermal transport material in the liquid state in the wicking material and in a gas state in the vapor cavities to transport thermal power over a distance from an evaporator region of the sealed housing to the heat exchangers. Furthermore, the heat exchangers transfer the thermal power from the sealed housing to an environment external to the heat pipe, and a product of the thermal power and the distance (which is sometimes referred to as the ‘heat transport requirement’) exceeds a second predetermined value. 
     For example, the predetermined value may be less than or equal to 1.4 mm and/or the second predetermined value may be larger than or equal to 2,000 W-mm. In some embodiments, the thermal power is greater than or equal to 35 W (such as 40 or 60 W). 
     Moreover, the thermal transport material may include water. 
     Furthermore, the sealed housing and the wicking material may include copper. Note that the wicking material may include sintered particles having diameters less than 500 μm. 
     In some embodiments, the vapor cavities are located at opposite sides of a cross-section of the sealed housing. 
     Additionally, during operation of the heat pipe, the sealed housing may reduce acoustic sound associated with bubbles of the gas phase of the thermal transport material. 
     Another embodiment provides a portable electronic device that includes the heat pipe and an integrated circuit that generate heat during operation of the portable electronic device. This integrated circuit may be thermally coupled to the heat pipe, such as proximate to the evaporator region of the sealed housing. 
     Another embodiment provides a method for cooling a portable electronic device. During operation of the portable electronic device, heat generated by an integrated circuit in the portable electronic device is transported over the distance from the evaporator region of the sealed housing in the heat pipe to the heat exchangers at the condenser regions of the sealed housing. This thermal power is transported via the two-phase bidirectional flow of the thermal transport material in the liquid state and in the gas state in the sealed housing, where the sealed housing has the height less than the predetermined value, and the product of the thermal power and the distance (or effective length) exceeds the second predetermined value. Then, using the heat exchangers, the thermal power is transferred from the sealed housing to the environment external to the portable electronic device. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  is a block diagram illustrating a bottom view of a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 2  is a block diagram illustrating a cross-sectional view of a system for facilitating heat transfer in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 3  is a block diagram illustrating a sectional view of a system for facilitating heat transfer in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 4  is a block diagram illustrating a side view of a thermal stage in accordance with an embodiment of the present disclosure. 
         FIG. 5  is a block diagram illustrating a wall in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 6  is a block diagram illustrating a rear view of a set of intake and exhaust zones in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 7  is a block diagram illustrating a cross-sectional view of a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 8  is a block diagram illustrating a cross-sectional view of a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 9  is a block diagram illustrating a gasket in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 10  is a block diagram illustrating a flexible portion of a gasket in accordance with an embodiment of the present disclosure. 
         FIG. 11  is a block diagram illustrating a flexible portion of a gasket in accordance with an embodiment of the present disclosure. 
         FIG. 12  is a flow chart illustrating a method of facilitating heat transfer in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 13  is a flow chart illustrating a method of facilitating heat transfer in a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 14  is a flow chart illustrating a method of assembling a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 15  is a block diagram illustrating a top view of a heat pipe in accordance with an embodiment of the present disclosure. 
         FIG. 16  is a block diagram illustrating a side view of the heat pipe of  FIG. 1  in accordance with an embodiment of the present disclosure. 
         FIG. 17  is a block diagram illustrating a top view of a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 18  is a flowchart illustrating a method for cooling a portable electronic device in accordance with an embodiment of the present disclosure. 
         FIG. 19  is a block diagram illustrating a portable electronic device in accordance with an embodiment of the present disclosure. 
     
    
    
     Note that like reference numerals refer to corresponding parts throughout the drawings. Moreover, multiple instances of the same part are designated by a common prefix separated from an instance number by a dash. 
     DETAILED DESCRIPTION 
       FIG. 1  shows a bottom view of a portable electronic device  100 , such as a laptop computer, with the bottom of the enclosure of portable electronic device  100  removed. Within portable electronic device  100 , a number of components may be used to cool heat-generating components such as central-processing units (CPUs), graphics-processing units (GPUs), and/or video memory. 
     First, portable electronic device  100  may include a set of fans  102 - 104  for expelling heat generated by the heat-generating components outside portable electronic device  100 . Fans  102 - 104  may utilize a set of intake and exhaust vents along a wall  118  of portable electronic device  100  to draw in cooler air from outside portable electronic device  100 , circulate the air around the interior of portable electronic device  100  to dissipate heat from the heat-generating components, and expel the heated air out of portable electronic device  100 . 
     Portable electronic device  100  may also include a heat pipe  106  that conducts heat away from one or more of the heat-generating components toward the flow of exhaust from fans  102 - 104 . For example, heat pipe  106  may be a sealed pipe of a thermally conductive material, such as copper, filled with a working fluid such as: water, ethanol, acetone, sodium, and/or mercury in a partial vacuum. The working fluid may evaporate to vapor at the thermal interface with a heat-generating component closer to the center of heat pipe  106 , migrate to an end of heat pipe  106  that is cooled by a fan (e.g., fans  102 - 104 ), and condense back into liquid after the heat is removed by the fan. A sintered material (e.g., metal powder) in the interior of heat pipe  106  may then exert capillary pressure on the condensed liquid, conducting the liquid back to the heated portion of heat pipe  106  for subsequent transfer of heat away from the heat-generating component. 
     To further facilitate heat dissipation from the heat-generating component, a thermal stage  108  may apply a spring force between heat pipe  106  and the heat-generating component. For example, thermal stage  108  may be bonded to heat pipe  106  using a solder and fastened to a surface within portable electronic device  100  using a set of fasteners  110 - 116  to increase the amount of heat transferred along a thermal interface between the heat-generating component and heat pipe  106 . 
     In one or more embodiments, heat-dissipation mechanisms and/or components in portable electronic device  100  may include a number of characteristics and/or features that increase the transfer of heat away from the heat-generating components and/or facilitate efficient use of space within portable electronic device  100 . First, fasteners  110 - 116  may both fasten thermal stage  108  to a surface within portable electronic device  100  and create a thermal gap between heat pipe  106  and the enclosure of portable electronic device  100 , as discussed below with respect to  FIG. 2 . Second, thermal stage  108  may include two thicknesses to reduce an overall thickness of portable electronic device  100  while maintaining the spring force necessary to adequately cool the heat-generating component over which thermal stage  108  and heat pipe  106  are disposed, as described in further detail below with respect to  FIGS. 3-4 . 
     Third, wall  118  may include intake vents that are directed at a first angle toward one or more heat-generating components of portable electronic device  100  and exhaust vents directed at a second angle out of portable electronic device  100  to avoid a display of portable electronic device  100 . Wall  118  may also include one or more obstructed vents between the intake and exhaust vents, as well as mechanisms for reducing the temperature of hot spots in the enclosure of portable electronic device  100 . Wall  118  is described in further detail below with respect to  FIGS. 5-8 . 
     Finally, a set of gaskets  120 - 122  may provide thermal ducts between fans  102 - 104  and exhaust vents in wall  118  to prevent exhaust from recirculating inside portable electronic device  100  and reducing the effectiveness of heat dissipation from the heat-generating components. As discussed below with respect to  FIGS. 9-11 , gaskets  120 - 122  may include a rigid section that forms the duct, as well as a set of flexible sections that simplify assembly of heat pipe  106  on top of the rigid section and subsequently seal the duct around heat pipe  106 . 
       FIG. 2  shows a cross-sectional view of a system for facilitating heat transfer in a portable electronic device  200  (e.g., portable electronic device  100  of  FIG. 1 ). The system includes heat pipe  106  and thermal stage  108 , both of which are disposed over a heat-generating component  202  such as a CPU and/or GPU. 
     As shown in  FIG. 2 , thermal stage  108  may be disposed along a thermal interface in between heat pipe  106  and heat-generating component  202 . A thermal interface material (TIM)  214  may also be disposed within the thermal interface between heat-generating component  202  and thermal stage  108  to increase the thermal contact conductance between heat-generating component  202  and thermal stage  108 . 
     In one or more embodiments, the spring force of thermal stage  108  is used to increase thermal contact between heat-generating component  202  and heat pipe  106 . For example, thermal stage  108  may improve heat conduction between heat-generating component  202  and heat pipe  106  by reducing the thickness and, in turn, the thermal resistance of TIM  214 . As a result, thermal stage  108  may be made of a material with a high thermal conductivity and spring constant, such as copper titanium. 
     To provide thermal contact between heat-generating component  202  and heat pipe  106 , heat pipe  106  may be joined to thermal stage  108  using a solder  216 - 218 , and thermal stage  108  may be fastened to a surface  208  within portable electronic device  200  using a set of fasteners  204 - 206  (e.g., fasteners  110 - 116  of  FIG. 1 ). For example, fasteners  204 - 206  may include one or more screws that fasten a set of wings of thermal stage  108  to a printed circuit board (PCB) containing heat-generating component  202 . Fasteners  204 - 206  and thermal stage  108  may thus apply downward force onto heat-generating component  202  and increase the thermal coverage of heat-generating component  202  by heat pipe  106 . 
     Fasteners  204 - 206  may additionally form a thermal gap  220  between heat pipe  106  and an enclosure  222  of portable electronic device  200 . Continuing with the above example, screws used to provide fasteners  204 - 206  may have tall heads  210 - 212  that provide a 0.5 mm-0.8 mm thermal gap  220  and/or plenum through which air may flow to further cool heat-generating component  202  and/or other heat-generating components in portable electronic device  200 . Alternatively, other types of fasteners  204 - 206  may be used to provide thermal gap  220 , including: clips, barbed fasteners, bolts, clamps, pins, pegs, and/or clasps. 
     Thermal gap  220  may also prevent heat pipe  106  from thermally contacting enclosure  222  if portable electronic device  200  is dropped and/or impacts another object. For example, fasteners  204 - 206  may be placed around heat-generating component  202  if heat-generating component  202  is located relatively far from an attachment point of a metal enclosure  222  to ensure that trampolining in enclosure  222  does not cause heat pipe  106  to transfer heat to enclosure  222  and/or a surface contacting enclosure  222 . Fasteners  204 - 206  may further be attached to a surface (e.g., the center of a PCB) with lower stiffness so that the impact does not damage heat-generating component  202  and/or other nearby components. 
     However, the proximity of fasteners  204 - 206  to enclosure  222  may result in physical contact between fasteners  204 - 206  and enclosure  222 . For example, fasteners  204 - 206  may touch enclosure  222  if fasteners  204 - 206  are designed to be intimate with enclosure  222  and/or if fasteners  204 - 206  are brought in contact with enclosure  222  during impact between enclosure  222  and a hard object. 
     As a result, fasteners  204 - 206  may include an insulating material to prevent fasteners  204 - 206  from heating enclosure  222  in the event of physical contact between the fasteners  204 - 206  and enclosure  222 . For example, fasteners  204 - 206  may be made of plastic to reduce thermal conduction between fasteners  204 - 206  and enclosure  222 . Consequently, fasteners  204 - 206  may improve thermal contact between heat-generating component  202  and heat pipe  106 , provide thermal gap  220  as a channel for airflow and/or heat dissipation from heat-generating component  202  and/or heat pipe  106 , and facilitate safe operation of portable electronic device  200  by thermally insulating enclosure  222  from heat-generating component  202  and/or heat pipe  106 . 
       FIG. 3  shows a sectional view of a system  300  for facilitating heat transfer in a portable electronic device. As mentioned above, system  300  may include heat pipe  106  and thermal stage  108 , both of which are disposed over a heat-generating component  302  (e.g., a CPU). Heat pipe  106  may be soldered to thermal stage  108 , and a set of wings  304 - 306  of thermal stage  108  may be fastened to a surface within the portable electronic device to apply a spring force to heat-generating component  302 . For example, the fastening of wings  304 - 306  that are angled upward to a PCB containing heat-generating component  302  may apply a downward force onto heat-generating component  302  and increase the thermal contact conductance between heat-generating component  302  and heat pipe  106 . 
       FIG. 4  shows a side view of thermal stage  108 . Thermal stage  108  may include a number of regions  404 - 406  with different thicknesses. In particular, region  402  may be of a first thickness, and regions  404 - 406  may be of a second thickness that is greater than the first thickness. 
     The first and/or second thicknesses may be created in thermal stage  108  using a number of techniques. For example, a machining technique may be used to form a trough in a material (e.g., copper titanium) of uniform stock thickness. Similarly, a profile corresponding to the first thickness may also be formed in raw stock using a rolling technique. The first thickness may further be created by removing material from uniform stock using a skiving technique, continuous machining technique, and/or chemical-etching technique. A forging and/or coining technique may be used to press the first thickness into uniform stock, or a casting technique may be used to form the first and second thicknesses from a mold. 
     As mentioned above, the first thickness may accommodate a heat pipe (e.g., heat pipe  106  of  FIG. 1 ). For example, the first thickness may form a notch and/or groove within which the heat pipe may be placed to reduce an overall thickness of the portable electronic device containing thermal stage  108  and the heat pipe. On the other hand, the second thickness may increase a spring force between a heat-generating component and the heat pipe, allowing for better thermal transfer between the heat-generating component (e.g., a high-power CPU) and the heat pipe. For example, the second thickness may be used in the wings (e.g., wings  304 - 306  of  FIG. 3 ) of thermal stage  108  to increase the downward force applied by thermal stage  108  and/or a set of fasteners (e.g., fasteners  110 - 116  of  FIG. 1 ) onto the top of the heat-generating component. Consequently, the first and second thicknesses may facilitate both efficient use of space within the portable electronic device and increased cooling of the heat-generating component by the heat pipe. 
       FIG. 5  shows wall  118 . Wall  118  may be a rear wall of a portable electronic device, such as a laptop computer. The rear wall may be integrated into a top case of the laptop computer to reduce the number of seams and/or components in the laptop computer&#39;s enclosure. For example, instead of creating wall  118  as a separate part and subsequently joining wall  118  to the top case, wall  118  may be machined out of the top case. In turn, the reduced number of seams and/or components in the enclosure may mitigate electromagnetic interference caused by the enclosure and/or improve the rigidity and/or height tolerance of the enclosure. 
     As shown in  FIG. 5 , wall  118  includes an intake zone  502  and two exhaust zones  504 - 506 . Intake zone  502  includes a set of intake vents around the center of wall  118  that allow a set of fans (e.g., fans  102 - 104  of  FIG. 1 ) to draw cooler air from the exterior of the portable electronic device into the portable electronic device. The fans may then circulate the air inside a set of plenums and/or thermal gaps (e.g., thermal gap  220  of  FIG. 2 ) within the portable electronic device and expel the heated air out of the portable electronic device through a set of exhaust vents in exhaust zones  504 - 506  on either side of intake zone  502 . As discussed in further detail below with respect to  FIGS. 7-8 , the intake vents may be directed at a first angle toward one or more heat-generating components of the portable electronic device, and the exhaust vents may be directed at a second angle out of the portable electronic device. 
       FIG. 6  shows a rear view of a set of intake and exhaust zones  502 - 506  of a portable electronic device. As described above, intake zone  502  may include a set of intake vents that are used by fans to draw in air from outside the portable electronic device, while each exhaust zone  504 - 506  may include a set of exhaust vents that are used by the fans to expel heated air out of the portable electronic device. 
     In addition, a set of obstructed vents  602 - 608  may separate intake zone  502  from exhaust zones  504 - 506 . Air flow from vents  602 - 608  may be blocked from the inside of the portable electronic device by a portion of a duct formed by a gasket in the portable electronic device, as described below with respect to  FIG. 10 . Such obstruction of substantially evenly spaced openings in intake and exhaust zones  502  and exhaust zones  504 - 506  may maintain the cosmetic continuity of the vents in intake and exhaust zones  502 - 506 , reduce electromagnetic interference from the enclosure of the portable electronic device, and facilitate heat dissipation in the portable electronic device by separating the intake and exhaust flows passing through intake and exhaust zones  502 - 506 , respectively. 
       FIG. 7  shows a cross-sectional view of a portable electronic device  700 . More specifically,  FIG. 7  shows a cross-sectional view of an exhaust vent  702  from an exhaust zone (e.g., exhaust zones  504 - 506  of  FIG. 5 ) in a wall (e.g., wall  118  of  FIG. 1 ) of portable electronic device  700 . Air from the interior of portable electronic device  700  may be moved by a fan (e.g., fans  102 - 104  of  FIG. 1 ) across heat pipe  106  and a heat sink  712 , where the air is heated and expelled as exhaust out of exhaust vent  702 . 
     In addition, two flows  704 - 706  of exhaust out of vent  702  may be created by a clutch barrel  710  connecting a display of portable electronic device  700  (e.g., a laptop computer) to the bottom portion of portable electronic device  700 . Flow  704  may exit portable electronic device  700  along the bottom of clutch barrel  710 , while flow  706  may exit portable electronic device  700  over the top of clutch barrel  710 . To prevent exhaust from changing the white point of and/or accelerating degradation in the display, exhaust vent  702  may be directed at an angle out of portable electronic device  700  so that exhaust flows  704 - 706  avoid the display and/or do not create a large temperature gradient across the display. If the display is closed over the bottom portion of portable electronic device  700 , flow  706  may cease, and all exhaust may be expelled out of vent  702  through an air gap between the bottom of portable electronic device  700  and clutch barrel  710 . 
     Those skilled in the art will appreciate that exhaust flowing out of exhaust vent  702  may also heat material in the wall near exhaust vent  702  and create a hot spot in the enclosure of portable electronic device  700 . As a result, a T-cut  708  may be made in the material to reduce the thickness of the material and, in turn, the transfer of heat through the material. At the same time, the thickness of the material between exhaust vent  702  and one or more intake vents in portable electronic device  700  may be maintained to facilitate lateral conduction of heat from exhaust vent  702  to the intake vent(s), thus further reducing the temperature of the hot spot. Consequently, the relatively large size of exhaust vent  702 , T-cut  708 , and/or ridges at the bottom of exhaust vent  702  may provide a lightweight structure with thermally minimal spars, a reduced conduction path to both the top and bottom enclosures of portable electronic device  700 , and a lateral conduction path between the exhaust and intake zones in the wall. 
       FIG. 8  shows a cross-sectional view of a portable electronic device  800 . In particular,  FIG. 8  shows a cross-sectional view of an intake vent  802  from an intake zone (e.g., intake zone  502  of  FIG. 5 ) in a wall (e.g., wall  118  of  FIG. 1 ) of portable electronic device  800 . Intake vent  802  may allow cooler air from outside portable electronic device  800  to be drawn into portable electronic device  800  by a fan (e.g., fans  102 - 104  of  FIG. 1 ) and circulated within portable electronic device  800  before being expelled as exhaust out of one or more exhaust vents (e.g., exhaust vent  702  of  FIG. 7 ) in the wall. 
     Two flows  804 - 806  of air may pass through intake vent  802  while a display of portable electronic device  800  (e.g., a laptop computer) is open. Flow  804  may enter portable electronic device  800  along the bottom of a clutch barrel  810  connecting the display to the bottom of portable electronic device  800 , while flow  806  may enter portable electronic device  800  from the top of clutch barrel  810 . If the display is closed over the bottom of portable electronic device  800 , flow  806  may cease, and all air drawn in through intake vent  802  may flow  804  from an air gap between the bottom of portable electronic device  800  and clutch barrel  810 . 
     Moreover, intake vent  802  may be directed at an upward angle toward a heat-generating component  808  of portable electronic device  800  to facilitate heat dissipation from heat-generating component  808 . For example, intake vent  802  may channel air over the top of a PCB containing video memory to cool the video memory and/or other heat-generating components at the top of the PCB. As a result, air passing through intake vent  802  may dissipate heat from heat-generating component  808  better than air passing through an intake vent that is not angled upwards into the interior of portable electronic device  800 . 
       FIG. 9  shows a gasket  902  (e.g., gaskets  120 - 122  of  FIG. 1 ) in a portable electronic device. As mentioned above, gasket  902  may form a thermal duct between a fan  910  and a set of exhaust vents in wall  118  to prevent exhaust from recirculating inside the portable electronic device and reducing the effectiveness of heat dissipation from heat-generating components in the portable electronic device. 
     As shown in  FIG. 9 , gasket  902  may include three portions  904 - 908 . A rigid portion  904  may be disposed around a bottom of heat pipe  106  to form the duct between fan  910  and wall  118 . Two flexible portions  904 - 906  may then be bonded to rigid portion  904  so that gasket  902  is manufactured as a single component instead of multiple components that require multiple steps to assemble into gasket  902 . For example, flexible portions  904 - 906  may be made of a rubber that is bonded to a rigid portion  904  made of plastic using an overmolding technique. 
     Portion  906  may be a flap that is open during assembly of heat pipe  106  in the portable electronic device to allow heat pipe  106  to be placed over portions  904  and  908 . Portion  906  may then be closed over heat pipe  106  and portions  904  and  908  to seal the duct around heat pipe  106  after the assembly. Portions  904 - 906  may further seal the duct around fan  910 , a bottom enclosure (not shown) of the portable electronic device, a top enclosure  912  of the portable electronic device, and/or exhaust vents in wall  118 . For example, portion  906  may fold over portions  904  and  908  to seal along the top of fan  910 , the top and/or sides of heat pipe  106 , and/or the bottom enclosure. On the other hand, portion  908  may be bonded to one or more edges of portion  904  and seal along the bottom of fan  910 , the bottom and/or sides of heat pipe  106 , top enclosure  912 , and/or wall  118 . Gasket  902  may also include an additional flexible portion  914  that seals the duct along wall  118 . Alternatively, portion  914  may be provided by a separate component (e.g., a gasket) disposed between gasket  902  and wall  118 . 
       FIG. 10  shows flexible portion  906  of a gasket (e.g., gasket  902  of  FIG. 9 ). As mentioned above, portion  906  includes a flap that is open during assembly of heat pipe  106  in the portable electronic device. For example, the portable electronic device may be assembled by placing the gasket into the top enclosure of the portable electronic device with portion  906  open over wall  118 . After the gasket is placed into the top enclosure of the portable electronic device, a part of rigid portion  904  may obstruct one or more vents in wall  118  to separate the intake and exhaust zones of wall  118 . Next, fan  910  may be placed next to the gasket, and heat pipe  106  may be placed on top of rigid portion  904  and/or a second flexible portion (e.g., portion  908  of  FIG. 9 ) of the gasket. 
       FIG. 11  shows flexible portion  906  of a gasket (e.g., gasket  902  of  FIG. 9 ). As shown in  FIG. 11 , portion  906  may be closed over heat pipe  106 , rigid portion  904 , and the second flexible portion after heat pipe  106  is assembled in the portable electronic device. The bottom enclosure of the portable electronic device may then be placed over the gasket to create a compression seal around heat pipe  106 , fan  910 , one or more exhaust vents of wall  118 , and/or the top enclosure of the portable electronic device. In addition, the insulating materials used in the gasket may restrict heat transfer between the exhaust and the enclosure of the portable electronic device, thus facilitating safe operation of the portable electronic device. 
       FIG. 12  shows a flow chart illustrating a method  1200  of facilitating heat transfer in a portable electronic device. During this method, a first thickness to accommodate a heat pipe in the portable electronic device and a second thickness that is greater than the first thickness to increase a spring force between the heat-generating component and the heat pipe are provided in a thermal stage (operation  1202 ). The thermal stage may be made of copper titanium and/or another material with a high thermal conductivity and/or spring constant. The first and/or second thicknesses may be created using a machining technique, a rolling technique, a skiving technique, a forging technique, a coining technique, a chemical etching technique, and/or a casting technique. 
     Next, a TIM is disposed between the heat-generating component and the thermal stage (operation  1204 ). For example, the TIM may be applied to a surface of the heat-generating component and/or the thermal stage. The thermal stage is then disposed along a thermal interface between the heat-generating component and the heat pipe (operation  1206 ), and the heat pipe is joined to the thermal stage using a solder (operation  1208 ). For example, the thermal stage may be placed over the heat-generating component, and the heat pipe may be placed over the thermal stage and soldered to the thermal stage. 
     The thermal stage is also fastened to a surface within the portable electronic device using a set of fasteners (operation  1210 ), and the set of fasteners is used to form a thermal gap between the heat pipe and the enclosure of the portable electronic device (operation  1212 ). For example, the fasteners may include screws with tall heads that form a plenum between the heat pipe and enclosure through which air may flow to further dissipate heat from the heat-generating component. The screws may also separate the heat pipe from the enclosure, thus preventing the heat pipe from transmitting large amounts of heat through the enclosure. Similarly, the heads of the screws may include an insulating material such as plastic to prevent the heat-generating component from thermally contacting the enclosure if the enclosure touches the screws&#39; heads (e.g., as a result of impact between the portable electronic device and a hard surface and/or by design). 
       FIG. 13  shows a flow chart illustrating a method  1300  of facilitating heat transfer in a portable electronic device. During this method, a wall of the portable electronic device that includes an intake zone containing a set of intake vents directed at a first angle toward one or more heat-generating components of the portable electronic device and an exhaust zone containing a set of exhaust vents directed at a second angle out of the portable electronic device is provided (operation  1302 ). For example, the wall may be a rear wall that is integrated into a top case of a laptop computer. The first angle may facilitate the cooling of components at the top of a PCB in the laptop computer, while the second angle may direct exhaust out of the laptop computer so that the exhaust avoids the display of the laptop computer. 
     Next, one or more vents between the intake zone and exhaust zone are obstructed (operation  1304 ). The vents may be obstructed by a portion of a duct between a fan and the exhaust zone and/or another component in the portable electronic device. The obstructed vents may maintain the cosmetic continuity of the portable electronic device while separating the intake and exhaust flows passing through the intake and exhaust zones. 
     Material adjacent to the exhaust vent may also be removed to reduce a temperature of a hot spot in the material during the transfer of exhaust out of the portable electronic device (operation  1306 ). For example, the material may be removed using a T-cut to reduce the amount of heat conducted through the material to the outside of the portable electronic device&#39;s enclosure. The temperature of the hotspot may further be reduced by maintaining the thickness of the material between the exhaust vent and one or more intake vents (operation  1308 ) in the portable electronic device. For example, the thickness of material separating the exhaust vent from an intake vent to the side of the exhaust vent may be maintained to facilitate lateral conduction of heat from the exhaust vent to the intake vent. 
       FIG. 14  shows a flow chart illustrating a method  1400  of assembling a portable electronic device. During this method, a gasket containing a rigid portion forming a duct between a fan and exhaust vent of the portable electronic device, with a first flexible portion containing a flap, and a second flexible portion bonded to one or more edges of the rigid portion, is placed within an enclosure of the portable electronic device (operation  1402 ). For example, the gasket may be placed inside a top enclosure of the portable electronic device so that one end of the gasket is flush with a wall (e.g., wall  118  of  FIG. 1 ) containing the exhaust vent, and a fan may be installed in the portable electronic device so that the other end of the gasket is flush with the fan. The rigid portion may be made of plastic, while the first and second flexible portions may be made of a rubber that is bonded to the rigid portion using an overmolding technique. 
     Next, a heat pipe is disposed over the rigid portion and second flexible portion while the flap is open (operation  1404 ). For example, the heat pipe may be assembled in the portable electronic device so that the heat pipe rests on top of the rigid portion and second flexible portion while the flap is open over the wall. 
     Moreover, the flap is closed over the heat pipe, the rigid portion, and the second flexible portion to seal the duct around the heat pipe (operation  1406 ). The first and second flexible portions may also seal the duct around the fan, the bottom enclosure of the portable electronic device, the top enclosure of the portable electronic device, and/or the exhaust vent. The gasket may thus prevent recirculation of exhaust within the portable electronic device, simplify the assembly of the heat pipe and/or portable electronic device, and/or insulate the enclosure of the portable electronic device from the heated exhaust. 
     We now describe additional embodiments.  FIG. 15  presents a block diagram illustrating a top view of a heat pipe  1500  that facilitates passive heat transfer. This heat pipe includes a sealed housing  1510 , having ends  1512 , which includes a thermal transport material (as described below with reference to  FIG. 16 ). Moreover, heat pipe  1500  includes heat exchangers  1514  (such as convective-cooling fins) that are thermally coupled to sealed housing  1510  at condenser regions  1516  of sealed housing  1510  proximate to ends  1512 . 
     As shown in  FIG. 16 , which presents a block diagram illustrating a side view of heat pipe  1500 , sealed housing  1510  has an outer surface  1610  and an inner surface  1612 , as well as ends  1512  ( FIG. 15 ). Furthermore, a height  1614  of sealed housing  1510  may be less than a predetermined value (such as less than or equal to 1.4 mm). For example, height  1614  may be 1.2 mm. This reduced height may facilitate the use of heat pipe  1500  in portable electronic devices with reduced form factors (as described further below with reference to  FIG. 17 ). 
     In existing heat pipes, reducing height  1614  to the predetermined value would adversely impact the heat-transport capability. However, the internal structure of heat pipe  1500  facilitates improved heat-transport capability at heights as small as 1.2 mm (or smaller). In particular, sealed housing  1510  includes a wicking material  1616  along at least a portion of inner surface  1612  and vapor cavities  1618  (where there is no wicking material  1616 ), and sealed housing  1510  includes a thermal transport material in a liquid state, such as water. 
     The geometry of this internal structure (such as the geometries of wicking material  1616  and vapor cavities  1618 ) may be optimized to maximize the thermal power transported by heat pipe  1500 . As illustrated in  FIG. 16 , in an exemplary embodiment vapor cavities  1618  are located at opposite sides of a cross-section of sealed housing  1510 , and wicking material  1616  may be along at least a portion of inner surface  1612 . A width  1622  of wicking material  1616  may be between 10 and 90% of width  1624  of sealed housing  1510 , while width  1624  may be 11-12 mm. Moreover, a height  1620  of wicking material  1616  may be between 10-90% of height  1614 . Furthermore, a thickness  1626  of sealed housing  110  may be between 0.1-0.5 mm, and wicking material  1616  may include sintered particles having diameters less than 500 μm. In some embodiments, sealed housing  1510  and wicking material  1616  may include copper (for example, they may be made of copper or a copper alloy). 
     During operation of heat pipe  1500 , sealed housing  1510  supports a two-phase bidirectional flow of thermal transport material in the liquid state in wicking material  1616  and in a gas state in vapor cavities  1618 . Referring to  FIG. 15 , thermal power (such as that associated with operation of one or more integrated circuits and, more generally, one or more components) is conductively coupled to sealed housing  1510  at evaporator region  1520  of sealed housing  1510 . Heat associated with the thermal power converts some of the thermal transport material from the liquid state to the gas state. The gas transports the thermal power from evaporator region  1520  to condenser regions  1516 , where it is transferred to heat exchangers  1514 . In the process, the thermal transport material condenses back into the liquid state, where a return flow to evaporator region  1520  occurs in wicking material  1616  in  FIG. 16 . Thus, the two-phase bidirectional flow transports thermal power over distances  1518  from an evaporator region  1520  to heat exchangers  1514 . 
     Furthermore, heat exchangers  1514  transfer the thermal power from sealed housing  1510  to an environment external to heat pipe  1500  (for example, in conjunction with forced-fluid drivers, such as fans, that force air over heat exchangers  1514 ), and a product of the thermal power and a distance (or effective length) equal to two times either of distances  1518  exceeds a predetermined value, which may be larger than or equal to 2,000 W-mm (such as 2,030 or 3,050 W-mm). For example, distances  1518  may each be 120 mm (so that two times either of distances  1518  is 240 mm), and the thermal power may be greater than or equal to 35 W (such as 40 or 60 W) with a heat flux of more than 27 W/cm 2  (such as 32 or 34 W/cm 2 ) 
     Note that heat pipe  1500  may also be designed so that, during operation of heat pipe  1500 , sealed housing  1510  may reduce acoustic sound associated with bubbles of the gas phase of thermal transport material. For example, the geometry of wicking material  1616  and vapor cavities  1618  in  FIG. 16  may be selected so that the bubbling noise that can occur as the gas phase moves through the liquid phase of the thermal transport material is reduced or eliminated. 
     Heat pipe  1500  may be included in an electronic device, such as a portable electronic device. This is shown in  FIG. 17 , which presents a block diagram illustrating a top view of portable electronic device  1700  that includes heat pipe  1500 . Moreover, integrated circuit (I.C.)  1710 , which generates heat during operation of portable electronic device  1700 , may be thermally coupled to heat pipe  1500  proximate to evaporator region  1520  of sealed housing  1510 . For example, integrated circuit  1710  may be thermally coupled to heat pipe  1500  by an intervening copper plate (not shown). In this way, thermal power may be transferred to heat pipe  1500 , which, as described previously, then passively conveys it out of portable electronic device  1700 . 
     We now describe embodiments of a method that can be performed using the preceding embodiments.  FIG. 18  presents a flowchart illustrating a method  1800  for cooling a portable electronic device, such as portable electronic device  1700  ( FIG. 17 ). During operation of the portable electronic device, heat generated by an integrated circuit in the portable electronic device is transported over the distance from the evaporator region of the sealed housing in the heat pipe to the heat exchangers at the condenser regions of the sealed housing (operation  1810 ). This thermal power is transported via the two-phase bidirectional flow of the thermal transport material in the liquid state and in the gas state in the sealed housing, where the sealed housing has the height less than the predetermined value, and the product of the thermal power and the distance (or effective length) exceeds the second predetermined value. Then, using the heat exchangers, the thermal power is transferred from the sealed housing to the environment external to the portable electronic device (operation  1812 ). 
     In some embodiments of methods  1200  ( FIG. 12 ),  1300  ( FIG. 13 ),  1400  ( FIG. 14 ) or  1800  there may be additional or fewer operations. Moreover, the order of the operations may be changed, and/or two or more operations may be combined into a single operation. 
     The above-described heat transfer mechanisms can generally be used in any type of electronic device. For example,  FIG. 19  illustrates a portable electronic device  1900  which includes a processor  1902 , a memory  1904  and a display  1908 , which are all powered by a battery  1906 . This portable electronic device may include: one or more program modules or sets of instructions stored in an optional memory subsystem (not shown). These sets of instructions may be executed by an optional processing subsystem (such as one or more processors) on a motherboard (not shown). Note that the one or more computer programs may constitute a computer-program mechanism. Moreover, instructions in the various modules in the optional memory subsystem may be implemented in: a high-level procedural language, an object-oriented programming language, and/or in an assembly or machine language. Furthermore, the programming language may be compiled or interpreted, e.g., configurable or configured, to be executed by the optional processing subsystem. 
     In some embodiments, functionality in these circuits, components and devices may be implemented in one or more: application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), and/or one or more digital signal processors (DSPs). Moreover, the circuits and components may be implemented using any combination of analog and/or digital circuitry, including: bipolar, PMOS and/or NMOS gates or transistors. Furthermore, signals in these embodiments may include digital signals that have approximately discrete values and/or analog signals that have continuous values. Additionally, components and circuits may be single-ended or differential, and power supplies may be unipolar or bipolar. 
     Portable electronic device  1900  may include one of a variety of devices that can include memory, including: a laptop computer, a media player (such as an MP3 player), an appliance, a subnotebook/netbook, a tablet computer, a smartphone, a cellular telephone, a network appliance, a personal digital assistant (PDA), a toy, a controller, a digital signal processor, a game console, a device controller, a computational engine within an appliance, a consumer-electronic device, a portable computing device, a digital camera, a personal organizer, and/or another electronic device, such as another type of battery-powered electronic device. 
     In order to cool heat-generating components in portable electronic device  1900 , portable electronic device  1900  may include a heat pipe that conducts heat away from the heat-generating components and/or one or more fans that expel the heat out of portable electronic device  1900 . 
     Portable electronic device  1900  may also include a thermal stage disposed along a thermal interface between a heat-generating component and the heat pipe. The thermal stage may include a first thickness to accommodate the heat pipe and a second thickness that is greater than the first thickness to increase the spring force between the heat-generating component and the heat pipe. The thermal stage may also be fastened to a surface within portable electronic device  1900  by a set of fasteners that form a thermal gap between the heat pipe and the enclosure of portable electronic device  1900 . 
     Moreover, in order to further facilitate cooling of the heat-generating components, a wall of portable electronic device  1900  may include an intake zone containing a set of intake vents directed at a first angle toward one or more of the heat-generating components. The wall may also include an exhaust zone containing a set of exhaust vents directed at a second angle out of the electronic device (e.g., to avoid a display of the electronic device). One or more vents may be obstructed between the intake and exhaust zones to separate the intake and exhaust zones. In addition, the temperature of a hot spot near an exhaust vent may be reduced by removing material adjacent to the exhaust vent and/or maintaining a thickness of the material between the exhaust vent and one or more intake vents. 
     Furthermore, a gasket may prevent the recirculation of exhaust inside the electronic device. The gasket may include a rigid portion that forms a duct between a fan and an exhaust vent. The gasket may also include a first flexible portion bonded to the rigid portion, as well as a second flexible portion bonded to one or more edges of the rigid portion. The first flexible portion may be a flap that is open during assembly of the heat pipe in the electronic device and closed over the heat pipe and the rigid portion to seal the duct around the heat pipe after the assembly. The first and second flexible portions may further seal the duct around the fan, the bottom enclosure of the electronic device, the top enclosure of the electronic device, and/or the exhaust vent. 
     While a portable electronic device was used as an illustration in the preceding discussion, in other embodiments the heat-transfer technique is included in an electronic device, such as a server, a desktop computer, a mainframe computer and/or a blade computer. Furthermore, alternative heat transfer components and/or materials may be used in heat pipe  1500  ( FIG. 15 ). 
     Additionally, one or more of the components may not be present in the  FIGS. 1-11  and  15 - 17 . In some embodiments, the preceding embodiments include one or more additional components that are not shown in  FIGS. 1-11  and  15 - 17 . Also, although separate components are shown in  FIGS. 1-11  and  15 - 17 , in some embodiments some or all of a given component can be integrated into one or more of the other components and/or positions of components can be changed. 
     In the preceding description, we refer to ‘some embodiments.’ Note that ‘some embodiments’ describes a subset of all of the possible embodiments, but does not always specify the same subset of embodiments. 
     The foregoing description is intended to enable any person skilled in the art to make and use the disclosure, and is provided in the context of a parti-cular application and its requirements. Moreover, the foregoing descriptions of embodiments of the present disclosure have been presented for purposes of illustration and description only. They are not intended to be exhaustive or to limit the present disclosure to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present disclosure. Additionally, the discussion of the preceding embodiments is not intended to limit the present disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.

Metadata:
Filing Date: 20121218
Publication Date: 20160308
Grant Date: 20160308
Priority Date: 20120608
Inventors: DEGNER BRETT W.
LEGGETT WILLIAM F.
NIGEN JAY S.
LIANG FRANK F.
TAN RICHARD H.
Assignee: APPLE INC
CPC Classifications: [{"code": "F28D15/0233", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K7/20318", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K7/20309", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K5/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/203", "inventive": true, "first": true, "tree": "[]"}, {"code": "F28D15/04", "inventive": true, "first": false, "tree": "[]"}, {"code": "F28D15/0275", "inventive": true, "first": false, "tree": "[]"}, {"code": "F28D15/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y10T29/49826", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K7/20336", "inventive": true, "first": false, "tree": "[]"}, {"code": "B23P15/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "F28D1/024", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K7/20336", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K5/02", "inventive": true, "first": true, "tree": "[]"}, {"code": "F28D1/024", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y10T29/49826", "inventive": false, "first": false, "tree": "[]"}, {"code": "F28D15/02", "inventive": true, "first": false, "tree": "[]"}, {"code": "F28D15/0275", "inventive": true, "first": false, "tree": "[]"}, {"code": "B23P15/26", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/203", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 49715139