| 摘要 |
PURPOSE:To easily form a low-cost tip by making the diameter of an annular surface large in inclined angle larger than the diameter to a small angle and arranging them in series in the axial direction. CONSTITUTION:Two annular surfaces are formed on a tool 1 round an axis 2 of rotation. The annular surfaces are formed so that they have different angles to the central axis of their circles and incline in the same direction. The diameter of the annular surface 3 large in the inclined angle is made larger than the diameter of the annular surface 4 of a small angle and arranged in series in the axial direction. The tool 1 comes in contact with the inclined surface of a ball pen tip 7 and is moved to the rear as it rotates. The end of the tip 7 is narrowed down and the ball 8 is held. In this way, the ball pen tip fan be calked continuously without generating eccentricity. |
