| 摘要 |
Disclosed is an ultra low temperature freezer in which a double pipe is formed so that a volume of the double pipe performing heat exchange between a refrigerant discharged from a condenser and a refrigerant discharged from an evaporator is 70% to 130% relative to that of an evaporation pipe, thereby lowering the temperature of the refrigerant by ultra low temperature as a cooling cycle of the refrigerant is repeated. In the ultra low temperature freezer including an evaporator having an evaporation pipe, a compressor, an expansion pipe, and a condenser, a first refrigerant pipe is provided between the condenser and the expansion pipe, and is connected between the condenser and the expansion pipe, and a second refrigerant pipe is connected between the evaporator and the compressor, and receives the first refrigerant pipe therein to form the double pipe. A volume difference between the volume of the second refrigerant pipe and the volume of the first refrigerant pipe is 70% to 130% relative to that of that evaporation pipe. The volume difference is a volume obtained by subtracting the first volume from the second volume, in which the first volume is calculated from the first refrigerant pipe on the basis of the inner diameter, and the second volume is calculated from the second refrigerant pipe on the basis of the outer diameter. |
