PURPOSE: In a pliable adapter or pipe connected to the inlet-outlet port of a manhole, to facilitate the connection by fitting a packing around the connection portion and utilizing contraction and expansion of the adapter or pipe.
CONSTITUTION: The bottom box 1b of a manhole formed of resin concrete has an integral fitting portion 8 projecting from the side wall to surround an inlet-outlet port 4a. An adapter 5 for pipe connection made of pliable materila is fitted therearound with a seal packing 7 near the connection end. The end portion of the adapter 5 is fastened with a fastener 9 such as a chain block to reduce the diameter; after insertion of reduced portion into the opening 4, the fastener 9 is removed to allow the adapter 5 to recover its shape so that the packing 7 snugly fits onto the internal surface of the opening 4.
TAKEMURA IKUROU
KUSAKABE TAMATAROU
KUSANO HIROSHI
