| 摘要 |
PURPOSE:To provide an in-pipe runner capable of curving at a T junction without contact with the internal wall of a pipe and increasing the capacity of its main body. CONSTITUTION:An in-pipe runner, which includes a cylindrical portion 22 of radius (r) and height (h), a main body 2 having semispherical portions 23, 24 of radius (r) combined at both ends of the cylindrical portion 22, wheels mounted on the main body, and a drive portion for driving the wheels, and self-travels inside piping 1 of a piping radius R including a T junction, is designed so that the center point of the main body moves on a circle of radius P which is in contact with both axes of the T junction. The radius (r) is smaller than a value calculated using [R<2>-{P<2>(3-2sq. rt. /2)}]1/2, and of angles theta between 0 deg. and 45 deg. at which the main body rotates and moves, the angle thetah at which the height (h) is at its minimum is calculated using cos<-1> (P/(P+R-r)), and the height (h) of the cylindrical portion is set to a value smaller than that calculated from (r) and (thetah) using [2X{PX(1-costhetah)+R-r}]/sinthetah. |
