| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ballpoint pen tip by which any user can obtain stable writing feeling and the tip end of a pipe is not bent even though excessive force is applied. <P>SOLUTION: A ball receiving seat 21 is formed by inwardly pushing, pressing and deforming the side wall in the vicinity of the tip end of the metal pipe 2. A tip end fringe part 22 is formed by inwardly pushing, pressing and deforming the tip end of the pipe 2, A ball 3 is rotatably held with the ball receiving seat 21 and the tip end fringe part 22. The pipe 2 is press inserted and fixed into securing hole 41 of the tip end of a holder 4 of a synthetic resin. The front outer surface of the holder 4 is formed into a conical shape tapered toward a front direction. The wall thickness T of the tip end of the holder is set to be 0.03 mm to 0.3 mm. The length L of the tip end of the pipe 2 projecting forward from the tip end of the holder 4 is set to be 0.5×D to 2.8×D when the diameter of the ball 3 is D. <P>COPYRIGHT: (C)2007,JPO&INPIT |
