| 摘要 |
PROBLEM TO BE SOLVED: To obtain an excellent preservation performance almost free from quality deterioration of a food, etc., by a method wherein in a casing formed of a heat insulating layer, a Peltier element which is thermally conductive to a thermal conductor having a heat transfer surface to a container space in the casing, is provided, and to the Peltier element, an electric energy is fed by controlling, in response to a temperature variation of the container space. SOLUTION: A Peltier element 55 and a case internal fan 57 are respectively driven by an energy supply from an element power source part 61 and a fan power source part 62 which are controlled by signals from a control unit 63. A detection signal of a temperature sensor 64 which is installed on the surface of a first thermal conductor 53 in the vicinity of where the Peltier element 55 is provided, is input in the control unit 63. For a rapid increase of the case internal temperature due to the opening of a heat insulating door 52, power is turned onto the Peltier element 55 through the signal of the temperature sensor, the control unit 63 and the element power source part 61, and when the case internal temperature becomes a freezing temperature or lower due to a rapid decrease of the temperature in the vicinity of the element 55, the case internal fan 57 is driven to avoid the freezing by the signal of the temperature sensor 64, and the case internal humidity is kept high, and as a result, the freshness of vegetables, etc., can be kept for a long period of time. |
