| 摘要 |
PURPOSE: A manhole cover device having an adjustable height is provided to easily finish the surrounding of a manhole cover and to prevent damage to the manhole cover. CONSTITUTION: A manhole cover device having an adjustable height comprises a support(10), a main body(20), and a cover(30). The support is formed in a cylindrical shape and has opened top and bottom. Screw treads are formed on the inner surface of the support. The support is placed in the inlet of a manhole. The main body is formed in a cylindrical shape. Screw threads are formed on the outer surface of the main body. A ring-shaped protrusion has a hanging protrusion is formed on the inner surface of the top end of the main body. The cover is inserted into the hanging protrusion of the main body and opens and closes the top end of the main body. |
