| 摘要 |
A tip-changeable rotary cutting tool in which a tip having axis-symmetrically arranged cutting edges is inserted into a groove that cuts across the center of the holder's front end is improved in machining precision, product precision, and machining performance. Forward-facing oblique locking faces 8 are provided axis-symmetrically at the front ends of jaws 3 of a holder 1. The locking faces 8 cross each other at a position a certain distance (one-third to two-thirds the width of the tip) away from the front end of the tool to lock backward-facing engaging faces 9 provided at some longitudinal midpoint position of a tip 5. The shortened distance between the cutting edge 6 and the locking position suppresses the runout deviation of the tip, decreasing the displacements of the cutting edges due to the runout deviation. A large chip pocket can also be provided. |
