| 摘要 |
PURPOSE: To suppress work hardening and to cut apart without generating any chip by surely feeding a cutting wheel into a tube wall by means of an elongated member supported movably in the longitudinal direction inside an elongated cutter main body which can be inserted into a tube to be cut. CONSTITUTION: A feed screw 62 is screwed into a cutter main body 44 so as to be engaged with a pin 48 in the axial direction, a ratchet 90 is mounted, and a claw 92 is installed to a rear bracket 102 and can be engaged/disengaged with/from the ratchet tooth according to the turning position of a cam 96. The feed screw 62 is screwed into the cutter main body 44 while the cutter main body 44 is rotated counterclockwise, and the pin 48 is moved forward so as to advance a cutting wheel 60 outward in the radial direction. In clockwise rotation, the feed screw 62 is released from the cutter main body 44, and the pin 48 is retracted by means of a return spring 66, so that a return plate spring 68 returns the wheel 60 to the non-cutting position. When a cam driven element is put on the highest outer circumference part of the cam 96 while the cutter main body 44 is rotated, the claw 92 is released from the tooth and the feed screw 62 is screwed into and not released from the cutter main body 44, so that the wheel 60 is advanced in the radial direction in every rotation of the cutter main body 44. |
