| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a cap type ballpoint pen that is controlled in abrasion of the bottom wall of the ball holding chamber, and is appropriate for long distance writing with a simple structure. <P>SOLUTION: The cap type ballpoint pen is formed by arranging an ink tank that receives the ball point ink in a shaft tube; placing at a bottom wall of a ball holding chamber, a ball that is made by detachably being equipped with the cap at an end of the shaft tube, making a ballpoint pen tip that is made by rotatably holding a part of the ball that projects from a chip end by caulking the chip end inside, a writing medium; and arranging an elastic body that seals up the chip end at an insertion part provided at the end of the cap body. A lubrication overlayer is provided on the surface of the chip end and/or the ball surface and the caulking angle of the chip end is ≥40° and ≤90°. <P>COPYRIGHT: (C)2013,JPO&INPIT |
