| 摘要 |
A sectional door, the guide rails of which are situated on both sides of the door opening for guiding the rollers of the sections and comprise a vertical portion and a horizontal portion, which is situated above the door opening, said portions extending into each other through the intermediary of an arcuate portion, wherein the arcuate portion is constructed symmetrically in relation to a plane, which is determined by the angle bisector of the sector angle associated with the arc and extends vertically relative to a plane which is fixed by the vertical and horizontal portions (4, 5) of the guide rails of one side of the door. <IMAGE> |
