Heat pipe and method of manufacturing the same

Abstract

Disclosed is a heat pipe comprising: an evaporating section, a heat insulating section, a condensing section and a porous sintered powder wick structure, in which the wick structure comprises sub-structures different from one another in at least one selected from group including material, shape and particle size, each of the sub-structures being arranged into each of the evaporating, heat insulating and condensing sections, in which the wick structure has a biporous distribution made through sintering of a powder mixture having various particle sizes to increase porosity and permeability of the wick structure, and in which the heat pipe has an asymmetric cross sectional shape in a radial direction. Powder having a large particle size is readily inserted into the heat pipe to simplify manufacture of the heat pipe while thermal conductivity of the heat pipe is not degraded compared to a conventional structure which is not eccentric.

What is claimed is:  
     
         1 . A wick structure composed of a porous sintered powder wick and arranged into a heat pipe which has functional sections including an evaporating section, a heat insulating section and a condensing section, the wick structure comprising: 
 a method disposing sub-structures different from one another in at least one selected from group including material, shape and particle size, each of the sub-structures being arranged into each of the evaporating, heat insulating and condensing sections, in order to elevate thermal conductivity, amount of heat transport and temperature-controlling performance of the heat pipe.    
     
     
         2 . The method in accordance with  claim 1 , further comprising adding an additive such as Co(NH 2 ) 2  inputted into sintering powder to generate a gas through thermal decomposition of the additive during sintering of a wick to increase porosity and permeability of the wick structure.  
     
     
         3 . The method in accordance with  claim 1 , further comprising an arrangement of a biporous distribution in a radial direction of the heat pipe asymmetrically through sintering of a powder mixture having various particle sizes, to increase porosity and permeability of the wick structure.  
     
     
         4 . The method in accordance with  claim 1 , further comprising manufacturing porous sintered powder wick composed of a powder mixture which contains materials including copper, nickel, graphite, carbon and diamond, each of the materials having shape and thermal conductivity different from one another, to improve a heat transfer ability of the heat pipe in a radial direction.  
     
     
         5 . The method in accordance with  claim 1 , further comprising an absorptive coating applied to the surface of the wick structure or particles constituting the wick structure to increase an ability of the wick structure absorbing a working fluid.  
     
     
         6 . The method in accordance with one of  claim 1  to  5 , further comprising an absorptive coating for increasing an ability of the wick structure for absorbing a working fluid, the absorptive coating is made of one selected from group including hydrates, hydroxides, carbonates and LiBr.  
     
     
         7 . The method in accordance with one of  claim 1  to  5 , wherein the wick structure and a coating applied to the wick structure are planar or cylindrical.  
     
     
         8 . The method in accordance with one of  claim 1  to  5 , further comprising an absorptive coating applied to the surface of the wick sub-structure of the evaporating section of the heat pipe or particles constituting the wick sub-structure of the evaporating section of the heat pipe.  
     
     
         9 . A heat pipe comprising an evaporating section, a heat insulating section, a condensing section and a porous sintered powder wick structure, 
 wherein the wick structure comprises sub-structures different from one another in at least one selected from group including material, shape and particle size, each of the sub-structures being arranged into each of the evaporating, heat insulating and condensing sections,    wherein the wick structure has a biporous distribution made through sintering of a powder mixture having various particle sizes to increase porosity and permeability of the wick structure, and    wherein the heat pipe has an asymmetric cross sectional shape in a radial direction.