| 摘要 |
<p>The drainage system (1) has a drainage pipe (7) and multiple drain duct (4) emptying into the drainage pipe. The drainage duct has drainage pipe extending perpendicularly into it with inflow end. A bell shaped cap covers the inlet of the drainage pipe and the area of the drainage pipe outer cover adjacent to the inlet, such that a drainage gap is unsealed between a sub area of the cap inner cover and the drainage pipe outer cover.</p> |
