Heat dissipation device

Abstract

A heat dissipation device includes a heat pipe and a heat sink. The heat sink defines a through hole with a diameter slightly smaller then an outer diameter of the heat pipe. The heat pipe is fixedly engaging in the through hole of the heat sink via interference fit. The heat pipe includes a tube defining an interspace therein, a first wick formed on an inner surface of the tube, working fluid received in the interspace of the tube, and a retaining structure. The retaining structure is received in the interspace of the tube and abuts the first wick of the tube to enhance a rigidity of the tube. A second wick is formed on an outer surface of the retaining structure and connects with the first wick of the tube.

1 . A heat dissipation device, comprising:
 a heat sink defining a through hole therein; and   a heat pipe having an outer diameter slightly larger than a diameter of the through hole of the heat sink and being fixedly engaging in the through hole via interference fit, the heat pipe comprising a tube defining an interspace therein, a first wick formed on an inner surface of the tube, working fluid received in the interspace of the tube, and a retaining structure received in the interspace of the tube and abutting the first wick on the tube to enhance a rigidity of the tube, and a second wick being formed on an outer surface of the retaining structure.   
     
     
         2 . The heat dissipation device of  claim 1 , wherein the heat sink comprises a main body and a plurality of dissipation fins, the main body being a quadrangular prism, the through hole being defined in a center of the main body, the plurality of dissipation fins extending generally away from a middle of the main body. 
     
     
         3 . The heat dissipation device of  claim 2 , wherein four ribs respectively extend from four corners of the main body, the dissipation fins at each lateral side of the main body are perpendicular to that lateral side of the main body and are located between two corresponding neighboring ribs, and outer ends of the dissipation fins at each lateral side of the main body and outer ends of the two corresponding neighboring ribs are coplanar. 
     
     
         4 . The heat dissipation device of  claim 1 , wherein the retaining structure comprises two plates perpendicularly crossing each other, lateral edges of each plate abutting the first wick, the interspace of the tube being separated into four axial channels by the retaining structure, and the second wick being formed on an outer surface of each plate. 
     
     
         5 . The heat dissipation device of  claim 1 , wherein the retaining structure comprises four plates, one of the four plates perpendicularly crossing the other three plates, lateral edges of each plate abutting the first wick, the interspace of the tube thereby being separated into eight axial channels by the retaining structure, the second wick being formed on an outer surface of each plate. 
     
     
         6 . The heat dissipation device of  claim 1 , wherein the retaining structure comprises a hollow core and a plurality of supporting fins extending from an outer circumferential surface of the core, lateral edges of each of the supporting fins abutting the first wick, the second wick being formed on an outer surface of each supporting fin and the outer circumferential surface of the core. 
     
     
         7 . The heat dissipation device of  claim 6 , wherein the core has a uniform outer diameter smaller than an inner diameter of the tube, each supporting fin being rectangular, a third wick being arranged in the core for providing a path for condensed working fluid to flow back to a vaporizing region of the interspace, and a channel being defined between each two neighboring supporting fins for moving of vaporized working fluid. 
     
     
         8 . The heat dissipation device of  claim 6 , wherein the core has an outer diameter gradually decreasing from bottom to top, a maximum outer diameter of the core being substantially equal to an inner diameter of the tube, each supporting fin being triangular, a channel being defined inside the core for moving of vaporized working fluid. 
     
     
         9 . The heat dissipation device of  claim 6 , wherein the core comprises an upper portion and a lower portion, the lower portion having an outer diameter gradually decreasing from bottom to top, the upper portion having a uniform outer diameter being not larger than a minimum outer diameter of the lower portion, a maximum outer diameter of the lower portion being approximately the same as an inner diameter of the tube, a channel being defined in the core for moving of vaporized working fluid, each supporting fin comprising an upper section being rectangular and a lower section being triangular. 
     
     
         10 . The heat dissipation device of  claim 9 , wherein the outer diameter of the upper portion of the core is smaller than the minimum diameter of the lower portion of the core, a generally annular step being formed at a top of the lower portion of the core, the step adjoining an outer periphery of a bottom of the upper portion of the core. 
     
     
         11 . The heat dissipation device of  claim 1 , wherein the tube of the heat pipe is open at two opposite ends thereof, two caps being fixed onto the two opposite ends of the tube to seal the tube, the retaining structure having a length in an axial direction smaller than that of the tube, the retaining structure attaching to one of the two caps and spaced a distance from the other one of the two caps, a third wick being formed on the one of the two caps and connecting with the first wick and the second wick. 
     
     
         12 . A heat pipe comprising:
 a tube defining an interspace therein;   a first wick formed on an inner surface of the tube;   working fluid received in the interspace of the tube; and   a retaining structure received in the interspace of the tube and abutting the first wick of the tube to enhance a rigidity of the tube, and a second wick being formed on an outer surface of the retaining structure and connecting with the first wick of the tube.   
     
     
         13 . The heat dissipation device of  claim 12 , wherein the retaining structure comprises two plates perpendicularly crossing each other, lateral edges of each plate abutting the first wick, the interspace of the tube being separated into four axial channels by the retaining structure, and the second wick being formed on an outer surface of each plate. 
     
     
         14 . The heat dissipation device of  claim 12 , wherein the retaining structure comprises four plates, one of the four plates perpendicularly crossing the other three plates, lateral edges of each plate abutting the first wick, the interspace of the tube thereby being separated into eight axial channels by the retaining structure, the second wick being formed on an outer surface of each plate. 
     
     
         15 . The heat dissipation device of  claim 12 , wherein the retaining structure comprises a hollow core and a plurality of supporting fins extending from an outer circumferential surface of the core, lateral edges of each of the supporting fins abutting the first wick, the second wick being formed on an outer surface of each supporting fin and the outer circumferential surface of the core. 
     
     
         16 . The heat dissipation device of  claim 15 , wherein the core has a uniform outer diameter smaller than an inner diameter of the tube, each supporting fin being rectangular, a third wick being arranged in the core for providing a path for condensed working fluid to flow back to a vaporizing region of the interspace, and a channel being defined between each two neighboring supporting fins for moving of vaporized working fluid. 
     
     
         17 . The heat dissipation device of  claim 15 , wherein the core has an outer diameter gradually decreasing from bottom to top, a maximum outer diameter of the core being substantially equal to an inner diameter of the tube, each supporting fin being triangular, a channel being defined inside the hollow core for moving of vaporized working fluid. 
     
     
         18 . The heat dissipation device of  claim 15 , wherein the core comprises an upper portion and a lower portion, the lower portion having an outer diameter gradually decreasing from bottom to top, the upper portion having a uniform outer diameter being not larger than a minimum outer diameter of the lower portion, a maximum outer diameter of the lower portion being approximately the same as an inner diameter of the tube, a channel being defined in the core for moving of vaporized working fluid, each supporting fin comprising an upper section being rectangular and a lower section being triangular. 
     
     
         19 . The heat dissipation device of  claim 18 , wherein the outer diameter of the upper portion of the core is smaller than the minimum diameter of the lower portion of the core, a generally annular step being formed at a top of the lower portion of the core, the step adjoining and an outer periphery of a bottom of the upper portion of the core. 
     
     
         20 . The heat dissipation device of  claim 12 , wherein the tube of the heat pipe is open at two opposite end thereof, two caps being fixed onto the two opposite ends of the tube to seal the tube, the retaining structure having a length in an axial direction smaller than that of the tube, the retaining structure attaching to one of the two caps and spaced a distance from the other one of the two caps, a third wick being formed on the one of the two caps and connecting with the first wick and the second wick.