Heat pipe with ultra-thin flat wick structure

Abstract

A heat pipe with an ultra-thin flat wick structure includes a shell and a wick structure disposed in the shell. The wick structure includes heat exchange zones and at least one liquid channel connected between the heat exchange zones which are divided into an evaporation portion and a condensation portion. Each of the heat exchange zones has a plane and a pressing surface opposite to the plane. A plurality of elongated concave surfaces are spacedly arranged on the pressing surface such that a respective steam channel is formed via each of the concave surfaces in the shell and a respective elongated wick structure connection is formed between each concave surface and the plane. Cut-out zones are formed at two sides of the liquid channel between the heat exchange zones in the shell.

What is claimed is: 
     
         1 . A heat pipe with an ultra-thin flat wick structure ( 2 ), comprising:
 a hollow shell ( 1 ) having a flat shape; and   a wick structure ( 2 ) disposed in the shell ( 1 ), the wick structure ( 2 ) comprising a plurality of heat exchange zones ( 20 ) and at least one liquid channel ( 21 ) connected between the heat exchange zones ( 20 ) divided into at least one evaporation portion and at least one condensation portion,   wherein each of the heat exchange zones ( 20 ) has a plane ( 200 ) and a pressing surface ( 201 ) opposite to the plane ( 200 ), wherein the plane ( 200 ) is attached to an inner wall ( 110 ) of the shell ( 1 ), wherein a plurality of elongated concave surfaces ( 202 ) are spacedly arranged on the pressing surface ( 201 ) such that a respective steam channel ( 101 ) is formed in the shell ( 1 ) via each of the concave surfaces ( 202 ) and a respective elongated wick structure connection ( 203 ) is formed between each concave surface ( 202 ) and the plane ( 200 ), wherein cut-out zones ( 102 ) are formed at two sides of the liquid channel ( 21 ) between the heat exchange zones ( 20 ) in the shell ( 1 ).   
     
     
         2 . The heat pipe according to  claim 1 , wherein the shell ( 1 ) further comprises another wick structure ( 2 ) such that the two wick structures ( 2 ) are stacked up and down with respective heat exchange zones ( 20 ) and the concave surfaces ( 202 ) on the opposite heat exchange zones ( 20 ) are up-and-down corresponding to each other to form the steam channels ( 101 ). 
     
     
         3 . The heat pipe according to  claim 1 , wherein an external contour of the shell ( 1 ) has a thickness below 0.5 mm. 
     
     
         4 . The heat pipe according to  claim 1 , wherein each heat exchange zone ( 20 ) of the wick structure ( 2 ) has penetrated heat transfer holes ( 203 ) on the concave surfaces ( 202 ) thereof 
     
     
         5 . The heat pipe according to  claim 1 , wherein a plurality of recesses ( 205 ) are recessed and disposed on each concave surface ( 202 ) of each heat exchange zone ( 20 ) of the wick structure ( 2 ) to make the adjacent steam channels ( 101 ) communicate with each other. 
     
     
         6 . The heat pipe according to  claim 1 , wherein each concave surface ( 202 ) of each heat exchange zone ( 20 ) of the wick structure ( 2 ) has a shape of a “V”, an arc, a rectangle, or a trapezoid. 
     
     
         7 . The heat pipe according to  claim 1 , wherein each concave surface ( 202 ) gradually expands or shrinks along a longitudinal direction of the wick structure ( 2 ). 
     
     
         8 . The heat pipe according to  claim 1 , wherein each concave surface ( 202 ) is extended and disposed along a longitudinal direction of the wick structure ( 2 ). 
     
     
         9 . The heat pipe according to  claim 1 , wherein a thickness of the wick structure ( 2 ) is below 0.25 mm. 
     
     
         10 . The heat pipe according to  claim 9 , wherein a minimum thickness of the respective elongated wick structure connection ( 203 ) ranges from 0.02 mm to 0.04 mm. 
     
     
         11 . The heat pipe according to  claim 10 , wherein the shell ( 1 ) has an upper wall ( 10 ), a lower wall ( 11 ) spaced with and opposite to the upper wall ( 10 ), and side edges ( 12 ) surrounding the outer edges of the upper wall ( 10 ) and the lower wall ( 11 ). 
     
     
         12 . The heat pipe according to  claim 11 , wherein the wick structure ( 2 ) is braid, fiber, sintered metal powder, or any combination thereof