| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a down-pipe joint capable of smoothly draining irrespective of the amount of rainfall.SOLUTION: The down-pipe joint has a cylindrical shape opening at both ends and both ends are connection sections 11 and 12 respectively to a down-pipe 2. The down-pipe joint has, on the inner peripheral surface, a throat part 14 in which a protruding amount toward an inner direction is the largest at the central part in an axis direction, and the protruding amount toward the inner direction gradually gets smaller toward both ends of the down-pipe joint.</p> |
