HERMETIC SEALING METHOD FOR THERMALLY INSULATING DOOR

PROBLEM TO BE SOLVED: To prevent intrusion of outer air through the gap of an outer door due to negative pressure in a cold source storage room at the time of operating a snow ice air conditioning system. SOLUTION: In a hermetic seal function for blocking intrusion of outer air through the gap of a conventional structure door 5 at a large opening in the outer wall for throwing snow and ice by the negative pressure in a cold source storage room at the time of operating a snow ice air conditioning system, the outer wall part of the cold source storage room is divided into a door of thermal insulating structure and a hermetic sealing unit thus blocking intrusion of outer air using a conventional door. An outer frame 1 at the opening, the thermal insulating door 5 and a hermetic sealing sheet winding holder 8 at the upper of the door are constructed such that a hermetic sealing sheet 7 can be pulled down. The hermetic sealing sheet 7 is provided with a fixing face in order to settle the sheet stably. The hermetic sealing sheet 7 is then pulled down and the periphery thereof is secured by a magnet belt 9. Consequently, a negative pressure is produced in the storage room and the sheet 7 is sucked to the gap and secured by the magnet belt 9 thus sealing the door hermetically. Finally, a door protection shutter is fixed and a winding holder 2 is disposed at the upper outer part.