Edge tip changing type rotary cutting tool

A tip-changeable rotary cutting tool comprising:

• a holder has at its front end a groove cutting across the center of the holder;
• a tip having axis-symmetrically arranged cutting edges inserted into the groove;
• the holder has jaws formed on opposite sides of the groove;
• the tip is tightly sandwiched between the jaws;
• and
• the tip can be removed from the jaws for replacement,
• the cutting tool being characterized by the conditions that:
• each of the jaws has a locking face at its front end;
• the locking faces face forward obliquely;
• the locking faces cross each other at a position a specific distance away from the front end of the tool when viewed in a plan view of the holder;
• the specific distance is defined as about one-third to two-thirds the width of the tip;
• each of the two main faces has an engaging face;
• the engaging faces protrude from the tip such that they increase the thickness of the tip;
• the engaging faces face backward obliquely so that they can be engaged with the corresponding locking faces;
• and
• the locking faces lock the engaging faces.