Ebullient cooling device

Abstract

A power card is accommodated in a vaporizing portion. Heat medium in the vaporizing portion is vaporized by heat generated at the power card so as to cool down the power card. A vapor passage and a condensing portion are connected to the vaporizing portion and a communication passage is provided at upper ends of the vapor passage and the condensing portion. The heat medium vaporized in the vaporizing portion moves up to the communication passage and to the condensing portion, so that the heat medium is condensed in the condensing portion and moves to the vaporizing portion. The condensing portion is arranged at an upstream side of the vapor passage in a direction of blowing air. A cross sectional area of the vapor passage is larger than that of the condensing portion.

What is claimed is: 
     
         1 . An ebullient cooling device comprising:
 a cooling object;   a vaporizing portion for cooling down the cooling object by vaporizing heat medium through heat exchange between the cooling object and the heat medium;   a condensing portion for condensing the heat medium through heat exchange between the heat medium and outside fluid, to thereby radiate heat of the heat medium to the outside fluid; and   a vapor passage for moving the heat medium vaporized in the vaporizing portion to the condensing portion,   wherein the ebullient cooling device is characterized in that;   the condensing portion moves the heat medium condensed in the condensing portion to the vaporizing portion,   the condensing portion and the vapor passage are so arranged to overlap with each other in a direction of flow of the outside fluid,   the condensing portion is arranged at an upstream side of the vapor passage in the direction of the flow of the outside fluid, and   a cross sectional area of the vapor passage is larger than that of the condensing portion.   
     
     
         2 . The ebullient cooling device according to  claim 1 , further comprising:
 multiple fluid-passage plate units, each of which has the condensing portion, the vapor passage and a communication passage for communicating the condensing portion and the vapor passage with each other,   wherein the multiple fluid-passage plate units are built up in a plate built-up direction, and   wherein a width of a vapor-passage forming portion of the fluid-passage plate unit in the plate built-up direction is larger than a width of a portion of the fluid-passage plate unit for the condensing portion in the plate built-up direction.   
     
     
         3 . The ebullient cooling device according to  claim 2 , wherein
 the communication passage is provided at an upper end of the fluid-passage plate unit in a vertical direction.   
     
     
         4 . The ebullient cooling device according to  claim 1 , further comprising:
 an outer fin provided at an outer side of the condensing portion so as to facilitate the heat exchange between the heat medium and the outside fluid.   
     
     
         5 . The ebullient cooling device according to  claim 1 , further comprising:
 an inner fin provided inside of the condensing portion so as to facilitate the heat exchange between the heat medium and the outside fluid.   
     
     
         6 . The ebullient cooling device according to  claim 1 , wherein
 a thermal resistance between the vapor passage and the outside fluid is higher than that between the condensing portion and the outside fluid.   
     
     
         7 . The ebullient cooling device according to  claim 1 , further comprising:
 a reinforcing member provided between the neighboring fluid-passage plate units for increasing pressure resistance of the vapor passage.   
     
     
         8 . An ebullient cooling device comprising:
 a cooling object;   a vaporizing portion for cooling down the cooling object by vaporizing heat medium through heat exchange between the cooling object and the heat medium;   a condensing portion for condensing the heat medium through heat exchange between the heat medium and outside fluid, to thereby radiate heat of the heat medium to the outside fluid; and   a vapor passage for moving the heat medium vaporized in the vaporizing portion to the condensing portion,   wherein the ebullient cooling device is characterized in that;   the condensing portion moves the heat medium condensed in the condensing portion to the vaporizing portion,   the condensing portion and the vapor passage are so arranged to overlap with each other in a direction of flow of the outside fluid,   the condensing portion is arranged at an upstream side of the vapor passage in the direction of the flow of the outside fluid,   the ebullient cooling device further comprises multiple fluid-passage plate units, each of which has the condensing portion, the vapor passage and a communication passage for communicating the condensing portion and the vapor passage with each other,   the multiple fluid-passage plate units are built up in a plate built-up direction, and   the communication passages of the neighboring fluid-passage plate units are communicated to each other.   
     
     
         9 . The ebullient cooling device according to  claim 8 , wherein
 the communication passage is provided at an upper end of the fluid-passage plate unit in a vertical direction.   
     
     
         10 . The ebullient cooling device according to  claim 8 , further comprising:
 an outer fin provided at an outer side of the condensing portion so as to facilitate the heat exchange between the heat medium and the outside fluid.   
     
     
         11 . The ebullient cooling device according to  claim 8 , further comprising:
 an inner fin provided inside of the condensing portion so as to facilitate the heat exchange between the heat medium and the outside fluid.   
     
     
         12 . The ebullient cooling device according to  claim 8 , wherein
 a thermal resistance between the vapor passage and the outside fluid is higher than that between the condensing portion and the outside fluid.   
     
     
         13 . The ebullient cooling device according to  claim 8 , further comprising:
 a reinforcing member provided between the neighboring fluid-passage plate units for increasing pressure resistance of the vapor passage.   
     
     
         14 . An ebullient cooling device comprising:
 a vaporizing portion filled with working fluid;   a partitioning member provided in the vaporizing portion for dividing an inside space of the vaporizing portion into a first sub-space and a second sub-space;   an electronic device accommodated in the first sub-space, so that the electronic device is cooled down by vaporizing the working fluid in the first sub-space; and   a core portion provided at an upper side of the vaporizing portion and having multiple fluid-passage plate units,   wherein each of the fluid-passage plate units comprises;   a pair of plate members fixed to each other to form therein a fluid passage;   a partitioning wall for diving an inside space formed between the pair of the plate members into an upstream side space and a downstream side space; and   a communication passage formed at an upper portion of the inside space formed between the pair of the plate members so as to communicate the upstream side and the downstream side spaces with each other,   wherein a lower end of the downstream side space is connected to the first sub-space of the vaporizing portion, so that vapor of the working fluid generated in the first sub-space moves up through the downstream side space to the communication passage, and   wherein a lower end of the upstream side space is connected to the second sub-space of the vaporizing portion, so that the working fluid flows from the communication passage to the second sub-space through the upstream side space.