PROBLEM TO BE SOLVED: To enable opening and closing of a skylight without using a motor, and to enable opening and closing of a skylight with an inexpensive structure.SOLUTION: Since a pulling coil spring shorter than the height size of a pushup arm is stretched between the ceiling of a house and the bottom or lower end of the pushup arm, the skylight is opened by the spring force of the short pulling coil spring, only when the pushup arm for pushing and opening the skylight is released from an operation rope and is free. Since the bottom of the pulling coil spring is pulled together with the bottom of the pushup arm by the operation rope when the operation rope is pulled, the skylight is closed and simultaneously the pulling coil spring is stretched.SELECTED DRAWING: Figure 5【課題】モータを使用しないでも天窓を開閉可能とし、かつ安価な構造で天窓を開閉可能とする。 【解決手段】押し上げアームの高さ寸法より短い引っ張りコイルバネがハウスの天井と前記押し上げアーム下端又は下端寄りとの間に張設してあるので、前記の短い引っ張りコイルバネのバネ力で天窓が開かれる。ただし、天窓を押し開ける押し上げアームが操作ロープから開放されて、押し上げアームが自由な場合に限る。この操作ロープを引くと、前記の引っ張りコイルバネの下端も前記の押し上げアームの下端と共に操作ロープで引っ張られるので、天窓が閉じられると共に引っ張りコイルバネは伸びた状態となる。【選択図】 図５
