| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an inner window for a double window which realises a heat insulation effect.SOLUTION: A double window 10 is constituted of an outer window 12 and an inner window 30. A frame 44 for supporting the periphery of a heat insulation board 42 is supported by a window frame 32, and the inner window 30 is oppositely arranged to the outer window 12, and a sealable inner space 80 is formed between the outer window 12 and itself. Opening parts 50 and 60 and opening-closing shutters 54 and 64 are provided in an upper part and a lower part of the frame 44. The lower side opening part 60 is provided with an opening valve 76 for opening only toward the outer window 12 side. When sunlight shines from outdoors, air in the inside space 80 is warmed, and a rising air current is generated. The warmed air flows in the indoors from the upper opening part 50, and indoor cold air flows in the inside space 80 from the lower opening part 60, thereby a convection flow of the air is generated. Even if a downward air current is generated when the air in the inside space 80 is cooled at night, the cold air does not intrude indoors by the opening valve 76 provided in the lower opening part 60.</p> |
