PURPOSE: To punch a pipe lining material properly by inserting a flexible shaft having a coupling and a rotary knife on the tip thereof into a branch pipe, lowering the shaft to the lining material along the branch pipe and turning the shaft under a pressing force when the knife has reached the lining material.
CONSTITUTION: A rotary knife 1 is inserted in a sewage tank and the like continuous to a branch pipe and pressed inward by pushing a flexible shaft 10. And when the cutting edge 2 of the rotary knife 1 has reached a lining material and stopped moving downward, the shaft 10 is turned manually or with power. The turning of the shaft 10 is transferred from a shaft 4 to the rotary knife 1 keyed to the tip thereof. In the course of turning, a shaft part 4 is relatively free from motion in the pipe even if exposed to reaction due to a cutting force with the cutting edge 2, because said part 4 is retained with a shaft retainer 6. Therefore, the lining material can be punched. According to the aforesaid constitution, a hole can be properly formed via the branch pipe, using a relatively simple device.
INOUE NAOTAKE
MURAKAMI SHINICHI
AKIMOTO SHIGEKI
| JPS5026033A | 1975-03-18 | |||
| JPS616007U | 1986-01-14 |