| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ballpoint pen tip which can inhibit the drying of ink at the apex or the leakage of ink caused by the catching of a coil spring for pressing the rear end of a ball and thereby, urging it forward by the inner perforated wall of the ballpoint pen and the consequent failure of the coil spring to push the rear end of the ball properly, and can suppress the appearance of a thin spot in handwriting to the utmost by securing an ink circulation passage. <P>SOLUTION: A coil like member having an outside diameter part in accordance with the through hole inside diameter in which a linear part of the coil spring is positioned and a small diameter part in accordance with the center hole diameter is covered and arranged on the linear part of the coil spring. <P>COPYRIGHT: (C)2012,JPO&INPIT |
