| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a pipe type ball-point pen chip capable of performing sufficient ink feeding on the back face of a ball during writing, having no possibility of generating huskiness and the interruption of handwriting during writing, and making ink outflow abundantly. <P>SOLUTION: The method for manufacturing the pipe type ball-point pen chip includes: a ball receiving seat forming step for forming a plurality of inward projecting parts 23 for a ball receiving seat on the inner peripheral face near the front end of a metal-made cylindrical body 2; a caulking step for then inserting the ball 3 and bending a narrowing edges 21 at the front end of the metal-made cylindrical body 2 inward into a circumferential shape; and a hammering step for pressing the ball 3 backward by a hummer 4, and pressing the ball 3 on front faces of the respective inward projecting parts 23 to secure gaps between inner faces of caulking parts 22 and the forward and backward direction of the ball 3 during writing. Before the hammering step, channels 23a extending in the radial directions are formed in advance on front faces of the respective inward projecting parts 23, and after the hammering step, the channels 23a are not completely crushed but are made to exist. <P>COPYRIGHT: (C)2011,JPO&INPIT |
