JPH07111315B

PURPOSE:To achieve high I.P.F. when ice is used as a heat accumulating material, by a method wherein an airtight space part, formed by an upper container, a lower container, and a plurality of heat transfer pipes for intercoupling the two containers, is filled with working fluid to form a heat pipe. CONSTITUTION:A refrigerant cooled by a freezer 8 is ted to a heat transfer pipe body 9, and cools and liquefies steam of working liquid 12 in an upper container 4. In this case, since a heat pipe is formed with the upper container 4, a lower container 5, and heat transfer pipes 7, the cold heat of the container 4 is instantaneously dispersed to the whole, and the thickness of ice coated and grown on the whole heat transfer surface of a cold heat accumulating tank 2 is uniformized. Further, a parallel lamination fin is formed, high I.P.F. (a ratio of generated ice to the effective volume of a heat accumulating tank) can be easily achieved. During dissipation of cold heat, a refrigerant is fed through a heat transfer pipe 11, and is instantaneously cooled by means ot the working liquid 12 in the container 5 to feed it to a cooling load 10, and smooth heat transfer can be achieved.