PURPOSE: A transformer which includes a heat radiation function is provided to reduce the temperature of a core to fixed temperature by effectively emitting heat created in a coil through a heat radiation pipe. CONSTITUTION: A pair of cores(18, 18") is formed into an E-shape. A voltage transformation coil part(11) is reeled on the central pillar of the pair of cores. The voltage transformation coil part drops or pressures voltage. A heat radiation pipe(10) is arranged in the inner side of the voltage transformation coil part. The heat radiation pipe is formed into a cylinder shape and releases heat created in the voltage transformation coil part. A heat induction pipe is inserted into the voltage transformation coil part and induces the heat to the heat radiation pipe. A heat interface material layer is coated on the heat radiation pipe and transfers the heat created in the voltage transformation coil part to the heat radiation pipe.
