| 摘要 |
PROBLEM TO BE SOLVED: To eliminate a difference in level at an entrance, to provide an excellent waterproof function, and to reduce a manufacturing cost through simple structure. SOLUTION: A drainage groove 4 is formed in the floor part of an entrance and the drainage groove is covered with a drain board, which is positioned flush with a floor in the vicinity of the entrance. An operation plate capable of effecting seesaw movement is arranged in the drainage groove 4 and a cut-off plate 10 is inserted through a through-hole 8 of the drain board and placed on one half part 13. This constitution sinks the cut-off plate 10 in the through- hole 8 when no water flows from a bath room 1 and raises the cut-off plate 10 through a rise of one half part 13 simultaneously with lowering of the other half part 14 of the cutoff plate 10 when water flows therefrom, and dams up a flow of water. |
