COOLING APPARATUS

PROBLEM TO BE SOLVED: To improve the heat radiating efficiencies of the heat radiating fins of a cooling apparatus while resource conservation is contrived against the fin material by extending a chimney duct upward from the periphery of the heat radiating fins. SOLUTION: In a transformer using a heat-pipe cooling apparatus, heat radiating fins 4 are attached to heat pipes 2 on the outside of a transformer case 5 and a chimney duct 1 is extended upward from the periphery of the fins 4. In addition, a heat collecting fins 3 are attached to heat pipes 2 in the case 5 and the main body 7 of the transformer and the heat collecting fins 3 are set up so that the main body 7 and fins 3 may be dipped in electrically insulating oil 6. The heat energy resulting from the heat generated from the main body 7 is collected by means of the heat collecting fins 3 through the oil 6 and transmitted to the heat radiating fins 4 through the heat pipes 2 and radiated on the natural convection of air. In this case, the speed of natural convection of air cooling the heat radiating fins 4 becomes faster, because the chimney duct 1 accelerates the natural convection of air collecting the heat from the heat radiating fins 4. Therefore, the heat radiating efficiencies of the heat radiating fins 4 are improved.