Lightweight heat pipe and method of making the same

Abstract

In a lightweight heat pipe and a method for making the lightweight heat pipe, a first hollow pipe and a second hollow pipe making of two different materials are provided. The first hollow pipe is disposed into the second hollow pipe along an axial direction of the second hollow pipe. An inner wall surface of the second hollow pipe is attached on an outer wall surface of the first hollow pipe to combine the first and the second hollow pipes as a pipe body of the heat pipe. An inner space of the first hollow pipe is then vacuumed, and the pipe body is sealed after the working fluid is filled in the inner space of the first hollow pipe to finish the heat pipe.

1 . A method of making a lightweight heat pipe, comprising steps of:
 a) preparing a first hollow pipe and a second hollow pipe making of two different materials;   b) disposing the first hollow pipe into the second hollow pipe along an axial direction of the second hollow pipe;   c) making an inner wall surface of the second hollow pipe attached on an outer wall surface of the first hollow pipe to combine the first and the second hollow pipe as a pipe body of the heat pipe; and   d) vacuuming an inner space of the first hollow pipe, and sealing the pipe body after working fluid is filled in the inner space of the first hollow pipe to finish the heat pipe.   
     
     
         2 . The method of  claim 1 , wherein the first pipe is made of copper and the second pipe is made of aluminum. 
     
     
         3 . The method of  claim 1 , wherein in the step a), a grooved wick structure is formed on an inner wall of the first pipe. 
     
     
         4 . The method of  claim 1 , in the step b), further providing a rod to pass through and dispose inside the first pipe. 
     
     
         5 . The method of  claim 1 , wherein in the step c), the second pipe is pulled from two ends by a tool to reduce an inner diameter of the second pipe so that the inner wall surface of the second pipe is attached on the outer wall surface of the first pipe. 
     
     
         6 . The method of  claim 5 , wherein in the step c), the second pipe is placed in a high temperature chamber to soften the material of the second pipe when pulling the second pipe. 
     
     
         7 . The method of  claim 1 , wherein in the step c), the second pipe is shrunk to have the outer wall surface of the first pipe and the inner wall surface of the second pipe closely attached to each other. 
     
     
         8 . The method of  claim 1 , wherein in the step c), the first pipe  1  is expanded to have the outer wall surface of the first pipe and the inner wall surface of the second pipe closely attached to each other. 
     
     
         9 . The method of  claim 1 , further comprising a cutting step to cut the pipe body in a predetermined length after the step c). 
     
     
         10 . A lightweight heat pipe comprising:
 a first pipe; and   a second pipe sheathed on the first pipe, an inner wall surface of the second pipe being attached on an outer wall surface of the first pipe,   wherein the first and the second pipes are made of two materials with different specific gravities.   
     
     
         11 . The heat pipe of  claim 10 , wherein the first pipe is made of copper and the second pipe is made of aluminum. 
     
     
         12 . The heat pipe of  claim 10 , wherein a wick structure is formed on an inner wall of the first pipe. 
     
     
         13 . The heat pipe of  claim 12 , wherein the wick structure is a mesh wick or a grooved wick. 
     
     
         14 . The heat pipe of  claim 13 , wherein a powder sintered wick is formed on the wick structure. 
     
     
         15 . The heat pipe of  claim 10 , wherein the first and the second pipes are flat pipes. 
     
     
         16 . The heat pipe of  claim 15 , wherein a screen mesh is located in the first pipe along a longitudinal direction thereof.