| 摘要 |
PROBLEM TO BE SOLVED: To provide a septic tank in which engagement projecting parts capable of preventing the distance between the confronted walls from being extended are hardly broken. SOLUTION: The septic tank is provided with a partition plate 2 partitioning the internal space into a plurality of treatment tanks at the inside of the upper tank part and the lower tank part vertically divided so as to be connectable each other and installed over the space between at least either confronted walls in the upper tank part or the lower tank part. The partition plate 2 is provided with a pair of engagement projecting parts 9 engaged with the recessed parts to be engaged provided at the confronted walls, respectively, and the pair of engagement projecting parts are engaged with the recessed parts to be engaged, respective, so as to prevent the widening of the space between the confronted walls. The engagement projecting parts are integrally formed at the partition plate so as to be projected at the side inner than the outer edge of the partition plate to the plate thickness thereof. COPYRIGHT: (C)2009,JPO&INPIT
|
