| 摘要 |
PROBLEM TO BE SOLVED: To provide a pipe closing instrument capable of passing through a pipe material, even if there is a portion smaller in inner diameter than the existing pipe in the pipe material when a new pipe material is connected to the existing pipe.SOLUTION: A pipe closing instrument includes: two disc bodies 11, 12 the outer diameters of which are D; elastic bodies 22, 24 the outer diameters of which are Din a natural state; a bar-like member 7 fixed to one disc body 11; and a cylindrical member 6 fixed to the other disc body and relatively rotatable with respect to the bar-like member 7. Positive rotation of the cylindrical member 6 with respect to the bar-like member 7 makes the outer diameters of the elastic bodies 22, 24 be equal to or larger than an inner diameter Dof a pipe to be closed, and negative rotation of the cylindrical member 6 with respect to the bar-like member 7 makes the outer diameters of the elastic bodies 22, 24 be equal to or smaller than an inner diameter Dof the pipe material through which they pass, and be equal to or larger than the outer diameters Dof the disc bodies, so that the D, D, D, Dsatisfy the following relationship of D>D>D>D. |
