| 摘要 |
PURPOSE: A manhole having a manhole cover lock function is provided to solve a problem that a manhole cover does not come off from a cover frame by a hanging or a malfunction according to corrosion. CONSTITUTION: A manhole having a manhole cover lock function comprises a cover frame (20), a manhole cover (30), a fixing unit (40), a fixing nut (50), an elastic spring (60), and an air-tightness ring (70). An operation projection (311) of the manhole cover is formed to be protruding in a bottom surface of the manhole cover so that a settling space (80) is prepared between the operation projection and a hanging projection (21) when screwing the manhole cover up the cover frame. The air-tightness ring is connected in a groove portion (32) of the manhole cover. An insertion projection is formed in a bottom surface in order to insert the air-tightness ring into the settling space. A first air-tightness projection is formed in a side of the hanging projection, and a second air-tightness projection is formed in a side of the operation projection. A water-tight is maintained between the insertion projections. |
