| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a ballpoint pen chip, by which, in cutting process during forming a radial groove, there is no occurrence of burr and no partial falling of materials, and a setting failure of a coil spring or the like for energizing a ball is hardly caused. <P>SOLUTION: As an inner hole of a ball holder for partially protruding a ball serving as a writing member from a tip opening to grip it, a front large-diameter part which becomes a ball gripping chamber is formed. A cutting fixture having a radially located cutter is inserted from the large-diameter part side, and radial grooves are bored in a ball-receiving seat which becomes a bottom part of the large-diameter part until a nonpenetration state. Then, from the rear part of the ball holder, a rear hole is bored from the backside of the ball-receiving seat, and the rear hole and the radial groove are penetrated. <P>COPYRIGHT: (C)2011,JPO&INPIT |
