| 摘要 |
A full-flowing drainage bowl for drainage of a roof is preferably circular with water inflow over its circumferential upper edge and has a central outflow opening in the bottom, which outflow opening has a plate (5) above the opening which is larger than the outflow opening. The surrounding edge of the plate is placed mainly in the plane of the surrounding roof plane. In order to improve the known designs so that the bowl can be arranged lowered in the roof plane and has a small height and prevents formation of vortex at the dimensioning flow amount, the plate (5) consists of an even part (6) which is concentric with the outflow opening (2) and larger than the outflow opening and has a ringshaped part (8) being bended upwardly from the circumferential edge of the concentric part. The under side of the even part (6) is placed not higher than the upper edge of the bowl and the ringshaped part (8) forms a circumferential gap (a) between itself and the upper edge of the bowl, the throughflow area of said gap (a) being larger than the throughflow area of the outflow opening (2). The diameter of the bowl decides the throughflow capacity of the bowl also when the depths of the bowl is kept small. |
