| 摘要 |
<p>PROBLEM TO BE SOLVED: To perform easily and quickly the connecting work of wires with a special portion and eliminate the restrictions of wire laying works, by providing a retractable joint connected with the base end portion of a bell mouth with a nearly flared front end portion connected through with the special portion, and by connecting an underground pipe with the retractable joint. SOLUTION: A connective duct sleeve 3 comprises a bell mouth 4 connected through with a special portion 1 and a retractable joint 5 connected with the base end portion of the bell mouth 4, and the sleeve 3 connects an underground pipe 2 with the retractable joint 5 to engage the pipe 2 internally with the joint 5 in the state of allowing the pipe 2 to move in its longitudinal direction. Thereby, it can be avoided surely that the duct sleeve 3 generates its positional discrepancy accidentally in the window frame of the special portion 1 in the case of fastening the duct sleeve 3 to the special portion 1, and therefore, the connecting work of the underground pipe 2 with the special portion 1 can be performed easily and quickly. Moreover, since the retractable joint 5 is connected with the base end portion of the bell mouth 4 to make the underground pipe 2 movable in its longitudinal direction, the total earthquake resistance of an underground multi-purpose duct for wires can be obtained similarly to conventional ones.</p> |
