| 摘要 |
PROBLEM TO BE SOLVED: To provide a ventilation window having a large numerical aperture exceeding 50% and capable of being simply and automatically opened and closed. SOLUTION: Vent holes 12, 13 are provided at the upper and lower positions dividing a window frame 11 into three, the vent holes 12, 13 are set to the full open state when sliding window doors 15, 16 are moved to a window door storage section 14 at the center of the window frame 11, and a large numerical aperture at about 2/3 of the window frame area is realized. A pulley 21 is provided at the upper section of the window frame 11, and the upper and lower window doors 15, 16 are connected and suspended by the rigging 23. The upper and lower window doors 15, 16 are made nearly equal in weight, the rigging 29 is fitted to the lower window door 16, and it is fixed to a winding device 30 wound by coil springs 34 made of a shape memory alloy. A weight 43 is fitted to the lower window door 16 to keep balance with the coil springs 34. |
