| 摘要 |
<p>PURPOSE:To reduce the wear of a die and to decrease scratch on a work in a bending machine by forming radius parts having a large diameter radius part on the shoulder part of die, providing clearance grooves in the bottom parts of die and further applying nitriding treatment to a lower die. CONSTITUTION:V-bending is applied to a work W by elevating the lower die 5 cooperating with an upper die 9 when the lower table 3 is elevated after placing the work W on the upside of the lower die 5. With the progress of this V-bending, bending is executed while the underside of the work W is slid on the curved surface of the radius part 15A or 15B which is formed on the lower die 5. Because the radius parts 15A, 15B have a large radius, the work is not scratched even when the work is slipped. Because clearance grooves 17A, 17B are formed on the V-bottoms of V-dies 11A, 11B and refuse by bending which is generated at the time of bending is dropped into these clearance grooves 17A, 17B, the work is prevented from being scratching with the refuse by bending. Since, nitriding treatment is applied to the lower die 5, the die is excellent in wear resistance and corrosion resistance and rust is prevented from being generated.</p> |
