| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ball-point pen tip which can inhibit the drying of an ink at the apex or the leakage of an ink due to 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 ball-point pen and the consequent failure of the coil spring to push the rear end of the ball properly. <P>SOLUTION: This ball-point pen tip is constituted of at least, the ball as a writing member and a ball holder which partially projects the ball from the apex opening of a communication hole and embraces the ball in freely rotating fashion, and has inwardly projecting parts for regulating the back transfer of the ball arranged radially in the communication hole. In addition, the ball-point pen tip has a spring insertion guide member, of a cylindrical shape having a through hole to the back transfer, which connects a small-diameter forward end opening part with a large-diameter rear end opening part by forming an inclined surface in a part or the entirety of the through hole. Besides, the spring insertion guide member which is of a cylindrical shape with an inclined part whose diameter shrinks forward, is arranged and also, receives a coil spring inserted into the spring insertion guide member. Thus the apex of the coil spring is brought into contact with the rear end of the ball. <P>COPYRIGHT: (C)2011,JPO&INPIT |
