| 摘要 |
<p>PURPOSE:To prevent the tip of a head from making contact with a rod and to prevent the damage of the head by pivotally mounting the one end of a leg part, composing a support tool, on a rod holding body, and holding the rod holding body to the center of a pipe by means of a running roller located to the leg part. CONSTITUTION:A support tool comprises a pair of rod holding bodies 1 and three leg parts 2 extending from the periphery of a rod holding body 1 to the inner surface of a pipe. The rod holding body 1 comprises a cylinder body 3 having both ends being opened, three rollers 4 arranged in a cylinder body 3, and a spring 5 through the force of which the rollers 4 are energized, and the rollers 4 constrain a rod 104 from three directions. Each leg 2 has an arm 10, a running roller 11 is mounted on the end part of the arm, and the running roller 11 is brought into contact with the inner surface of an existing pipe 103 through the force of a spring 12. The arm 10 is mounted capable of being put in a turning movement on the cylinder body 3 by means of a pivotal fitting part 13. This constitution holds the rod holding body 1 in the center of a pipe and thus, the rod 104 is also held in the center of the pipe.</p> |
