Loop heat pipe with different pipe diameters

Abstract

A loop heat pipe with different pipe-diameters includes: an evaporation chamber having a casing and a wick disposed therein, the wick not occupying the casing fully such that an evaporation space is formed therebetween; a condensation element externally provided with a heat-dissipating unit and internally having a circulation channel, the circulation channel having a vapor connection-end and a liquid connection-end having a smaller inner diameter than the vapor connection-end; a vapor delivery-pipe having an end connecting to the casing and communicating with the evaporation space and another end connecting to the vapor connection-end of the condensation element and communicating with the circulation channel; and a liquid delivery-pipe having an end connecting to the casing and communicating with the casing and another end connecting to the liquid connection-end of the condensation element and communicating with the circulation channel, the liquid delivery-pipe having a smaller inner diameter than the vapor delivery-pipe.

What is claimed is: 
     
         1 . A loop heat pipe with different pipe diameters, comprising:
 an evaporation chamber having a casing and a wick disposed in the casing, the wick not occupying the casing fully so as for an evaporation space to be formed between the wick and the casing;   a condensation element externally provided with a heat-dissipating unit and internally having a circulation channel, the circulation channel having an end configured to be a vapor connection end and another end configured to be a liquid connection end, wherein the vapor connection end has a greater inner diameter than the liquid connection end;   a vapor delivery pipe having an end connecting to the casing and being in communication with the evaporation space and another end connecting to the vapor connection end of the condensation element and being in communication with the circulation channel; and   a liquid delivery pipe having an end connecting to the casing and being in communication with the inside of the casing and another end connecting to the liquid connection end of the condensation element and being in communication with the circulation channel, wherein the liquid delivery pipe has a smaller inner pipe diameter than the vapor delivery pipe.   
     
     
         2 . The loop heat pipe with different pipe diameters according to  claim 1 , wherein the casing comprises a lid and a receiving box, with the wick disposed in the receiving box, the lid covering the receiving box, the receiving box being defined by sidewalls each having a first hole and a second hole, wherein the first hole, the second hole and the evaporation space are positioned on a same side of the receiving box, the first hole having a greater diameter than the second hole, the first hole being in communication with the vapor space and penetrated by an end of the vapor delivery pipe so as to connect to the casing, and the second hole being penetrated by an end of the liquid delivery pipe so as to connect to the casing. 
     
     
         3 . The loop heat pipe with different pipe diameters according to  claim 2 , wherein the condensation element is a hollow-cored, U-shaped pipe, with the circulation channel disposed in the U-shaped pipe and penetrating to reach two ends of the U-shaped pipe, the two ends being configured to be the vapor connection end and the liquid connection end, respectively, the vapor connection end having a greater inner diameter than the liquid connection end. 
     
     
         4 . The loop heat pipe with different pipe diameters according to  claim 1 , wherein the casing comprises a lid and a receiving box, with the wick disposed in the receiving box, the lid covering the receiving box, the receiving box being defined by sidewalls each having a first hole and a second hole, wherein the first hole and the evaporation space are positioned on a same side of the receiving box, whereas the first hole and the second hole are positioned on different sides of the receiving box, respectively, the first hole having a greater diameter than the second hole, the first hole being in communication with the vapor space and penetrated by an end of the vapor delivery pipe so as to connect to the casing, and the second hole being penetrated by an end of the liquid delivery pipe so as to connect to the casing. 
     
     
         5 . The loop heat pipe with different pipe diameters according to  claim 4 , wherein the condensation element is a hollow-cored tube, with the circulation channel disposed in the hollow-cored tube and penetrating to reach two ends of the hollow-cored tube, the two ends being configured to be the vapor connection end and the liquid connection end, respectively, the vapor connection end having a greater inner diameter than the liquid connection end. 
     
     
         6 . The loop heat pipe with different pipe diameters according to  claim 2 , wherein the condensation element is a rectangular block having therein a pipeline for forming the circulation channel such that two ends of the pipeline form the vapor connection end and the liquid connection end, respectively, allowing the vapor connection end and the liquid connection end to protrude from the block, the vapor connection end having a greater inner diameter than the liquid connection end. 
     
     
         7 . The loop heat pipe with different pipe diameters according to  claim 1 , wherein the wick is made of sintered copper powder and has a plurality of channels each having a channel opening in communication with the vapor space.