Device for opening manhole covers placed at ground level, particularly for sewer-inspection manholes

摘要

A tube 19 which surrounds, in a telescopic manner, a tube 23 supported by the floor 1 of the sewer installation is fixed at the surface of the cover 9 used to close off sewer manholes and the like. A pin 27 is placed inside these tubes 19, 23, making it possible, by means of a key 35, to extract the cover 9 from the frame 5 surrounding the manhole 3 and to cause it to pivot. The preliminary free travel of the pin 27 makes it possible conveniently to clean the end-piece 31 intended to receive the key 35. IMAGE