| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain a tubular ball-point pen tip, by which the bending strength of a tube can be improved without increasing the number of parts and, at the same time, a ball accepting seat with a proper shape can easily be formed. <P>SOLUTION: In the tubular ball-point pen tip 1, a ball 3 is rotatably held at the tip of the metal tube 2. The metal tube 2 is equipped with a thin wall part 4 formed at the tip part and a thick wall part 5 continuously connecting rearwards with the thin wall part 4. On the outer peripheral surface of the thin wall part 4, a plurality of dents 6 are formed by punching. At the same time, on the inner peripheral surface of the thin wall part 4 positioning the dents 6, a plurality of inwards projecting parts 7 for the ball accepting seat are formed. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
