| 摘要 |
A cylindrical plastic container 2 and lid 3; the container having an annular wedge shaped rib 9 on the inner surface 4 of its wall 8 below the top edge 5; and the lid having a downward section 7a and an upward section 7b with a groove 10 on its outer surface; the rib engaging the groove along upper 11 and lower 12 contact portions, and with a gap z between the tip 9a of the rib and the bottom 10a of the groove. Ideally there is a thin portion 15 between the downward and upward sections of the lid. The upper surface 10b of the groove could be flat and the upper surface 9b of the rib could be sloped. The lower surface 10c of the groove could be sloped and the lower surface 9c of the rib could be less steeply sloped or flat. The lower contact region could be deeper in the groove than the upper contact region. |
