| 摘要 |
PROBLEM TO BE SOLVED: To improve shape holding property by restricting a shape at the time of cam expansion in more than one circular grooves formed on the outer surface of a cuff by means of reinforcing bands provided in the periphery of a cam. SOLUTION: The caff 2 is provided in the patient side end part 3 of the plastic and bending tubal shaft 1 so as to enclose it. At least one circular grooves 20 and 21 are provided on the external surface of the caff 2 separatedly in a longitudinal direction. Then, division is executed into a patient side end part taper area 22, a patient end part contact area 23, a first patient side end part groove 20, an intermediate contact area 24, a second machine side end part groove 21, a machine side end part contact area 25 and a machine side end part taper area 26. The reinforcing bands 40 and 41 are provided in the periphery of the caff 2 and reinforced by forming the bottom floors of the grooves 20 and 21 and the reinforced area is prevented from being expanded to an outer side by a degree being the same as that of other adjacent areas. Thus, the cuff 2 is protected from the influence of deformation in a windpipe, etc., with the expansion. |
