| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to smoothly write without disconnecting a line by utilizing a powder core. SOLUTION: A magnetic writing ball 3 is rotatably engaged with the end of a nonmagnetic tip 2 interlocked to a nonmagnetic core cylinder 1, a powder core 4 obtained by mixing magnetizable metal powder with carbon powder or other dye powder is contained in the cylinder 1. The rear part of the cylinder 1 is openable by a cap 5, a pressing valve 7 is provided at the inside of the cap 5 via a spring 6, and is capable of pressing the core 4 in the cylinder 1 in the writing sphere direction. |
