| 摘要 |
PURPOSE: A multiple wall coupling trap with improved functions is provided to prevent offensive odors from leaking to the outside by closely coupling a vertical upper pipe to the inside the trap. CONSTITUTION: A multiple wall coupling trap with improved functions is comprised as follows. Three water tank walls(2,5,8), two cover walls(13,16), and a cover inner tube are coupled to each other and fixed. A vertical upper pipe is closely coupled to the inside a trap of a surface water hole. |
