Abstract: This cooling apparatus can improve a radiation performance by increasing the boiling area and make it difficult to cause the burnout on boiling faces by filling the boiling faces with a refrigerant necessary for the boiling. In refrigerant chambers for reserving a refrigerant, there are inserted corrugated fins for increasing the boiling area. These corrugated fins are composed of lower corrugated fins arranged to correspond to the lower sides of the boiling faces for receiving the heat of a heating body, and upper corrugated fins arranged to correspond to the upper sides of the boiling faces, and these lower and upper corrugated fins and are individually held in thermal contact with the boiling faces of the refrigerant chambers. The lower corrugated fins and the upper corrugated fins are given a common fin pitch P and are individually inserted vertically in the individual refrigerant chambers to define the individual passages further into a plurality of small passage portions.

Abstract: This cooling apparatus can improve a radiation performance by increasing the boiling area and make it difficult to cause the burnout on boiling faces by filling the boiling faces with a refrigerant necessary for the boiling. In refrigerant chambers for reserving a refrigerant, there are inserted corrugated fins for increasing the boiling area. These corrugated fins are composed of lower corrugated fins arranged to correspond to the lower sides of the boiling faces for receiving the heat of a heating body, and upper corrugated fins arranged to correspond to the upper sides of the boiling faces, and these lower and upper corrugated fins and are individually held in thermal contact with the boiling faces of the refrigerant chambers. The lower corrugated fins and the upper corrugated fins are given a common fin pitch P and are individually inserted vertically in the individual refrigerant chambers to define the individual passages further into a plurality of small passage portions.