Heat pipe

Abstract

A heat pipe includes a casing and a three-dimensional cross-linkage wick structure received in the casing. The three-dimensional cross-linkage wick structure has a plurality of pores therein for providing a capillary action and includes a bottom layer being attached to the casing and a plurality of protrusions extending from the bottom layer and spaced from each other. A groove is defined between two adjacent protrusions. The bottom layer has a connecting portion under the groove. The connection portion is formed between and connects with the two adjacent protrusions. The connection portions have a smaller pore size than the protrusions.

1  A heat pipe comprising:
 a casing;   a three-dimensional cross-linkage wick structure received in the casing and having a plurality of pores therein for providing a capillary action, the three-dimensional cross-linkage wick structure comprising:   a bottom layer being attached to the casing; and   a plurality of protrusions extending from the bottom layer and spacing from each other, a groove being defined between two adjacent protrusions, the bottom layer having a connection portion just under the groove, the connection portion being formed between and connecting with the two adjacent protrusions, the connection portion having a smaller pore size than the protrusions.   
     
     
         2 . The heat pipe as claimed in  claim 1 , wherein the casing is flat and has an upper plate and a bottom plate being located under the upper plate, the bottom layer of the three-dimensional cross-linkage wick structure being flat and attached to the bottom plate, a top of each of the protrusions abutting on the upper plate. 
     
     
         3 . The heat pipe as claimed in  claim 2 , wherein the groove defined between the two adjacent protrusions is provided as a vapor channel. 
     
     
         4 . The heat pipe as claimed in  claim 1 , wherein the casing is round, the bottom layer being attached to an inner peripheral surface of the casing, the protrusions extending radially and inwardly from the bottom layer toward a center of heat pipe. 
     
     
         5 . The heat pipe as claimed in  claim 1 , wherein a shape of each of the protrusions is selected from a group consisting of trapezium, triangle, and rectangle. 
     
     
         6 . A heat pipe comprising:
 a casing;   a three-dimensional cross-linkage wick structure received in the casing and having a plurality of pores therein for providing a capillary action, the three-dimensional cross-linkage wick structure comprising:   a bottom layer being attached to the casing;   a plurality of protrusions extending from the bottom layer and spacing from each other, a groove being defined between two adjacent protrusions, the bottom layer having a connection portion just under the groove, the connection portion being formed between and connecting with the two adjacent protrusions; and   a working medium saturated in the pores of the wick structure;   wherein the connection portions have a smaller pore size than the protrusions, the connection portions have a larger capillary force for the working medium in comparison with the protrusions, and the protrusions have a lower flow resistance for the working medium in comparison with the connection portions.   
     
     
         7 . The heat pipe as claimed in  claim 6 , wherein the casing is flat and has an upper plate at a top side thereof and a bottom plate at a bottom side thereof, the bottom layer of the three-dimensional cross-linkage wick structure being flat and attached to the bottom plate, a top of each of the protrusions abutting on the upper plate. 
     
     
         8 . The heat pipe as claimed in  claim 7 , wherein the groove defined between the two adjacent protrusions is provided as a vapor channel. 
     
     
         9 . The heat pipe as claimed in  claim 6 , wherein the casing is round, the bottom layer being attached to an inner peripheral surface of the casing, the protrusions extending radially and inwardly from the bottom layer toward a center of the heat pipe. 
     
     
         10 . The heat pipe as claimed in  claim 6 , wherein a shape of each of the protrusions is selected from a group consisting of trapezium, triangle, and rectangle.