| 摘要 |
<p>PROBLEM TO BE SOLVED: To ensure a smooth insertion without hurting entails by making the flexible tube constituting the insertion part bend in a smooth shape. SOLUTION: The flexible pipe 12A consists of a soft outer skin tube 60 and a hard outer skin tube 61 which is of a higher hardness than the soft outer skin tube 60. As shown by a graph, the hardness of the flexible pipe 12A shows that it is set at a softest level as indicated by a solid line, when a hardness regulating wire to be introduced through a coil pipe 39 is not pulled as a soft state. On the outer hand, the hardness of the flexible pipe 12A is caused to change to a softest state part S, a hard state part H and a hardest state part Hm in that order from the tip side of the flexible pipe 12A and thereby the change of the hardness is minimized, when the coil pipe 39 is compressed most strongly by pulling the hardness regulating wire to the maximum possible extent.</p> |
