| 摘要 |
In a window comprising a frame and a leaf and means for permitting forced ventilation in the closed state, the forced ventilation path extends over a fitting groove (21) in a horizontal casement leg, a ventilation louvre (4) being fitted such that it can swing in the fitting groove. In its rest position, the ventilation louvre (4) allows air to circulate through the fitting groove, but when greater flow pressure acts on the louvre it is deflected into a position which throttles or blocks the passage of air. |
