| 摘要 |
This replaceable head cutting tool increases the strength of engagement between a coupling member and the tool body without causing damage to the tool body or the punch. A cylindrical mounting unit (21) of the coupling member (2), which is made of a metal material less hard than that of the tool body (1), is inserted into a mounting hole (16) having a concave portion (17) on the inner surface of the tool body (1) made of a hard material, the mounting unit (21) is plastically deformed so as to increase in diameter such that the outer peripheral surface thereof is in close contact with the inner peripheral surface of the mounting hole (16) and engages with the concave portion (17), coupling the tool body (1) and the coupling member (2). The concave portion (17) has a first wall surface (17a) which inclines towards the outer peripheral side as said first wall surface goes in the insertion direction (F) of the mounting unit (21), and a second wall surface (17b) which is opposite of the first wall surface (17a) and which inclines towards the inner peripheral side as said second wall surface goes in the insertion direction (F). The first inclination angle alpha formed between the vertical plane (S) and the center line of the mounting hole (16) at the position where the first wall surface (17a) intersects the inner peripheral surface of the mounting hole (16) is set to less than the second inclination angle beta relative to the plane (S) at the position where the second wall surface (17b) intersects the inner peripheral surface of the mounting hole (16). |
