| 摘要 |
This drafting pen has an improved internal structure in which a plurality of air holes perforate the upper periphery of a sub shaft, a cover with a knob provided at a distance from the holes and a lower wavy end engages with the vicinity of the base of a needle with a weight, so that ink and air can mix and the phenomenon of ink accumulating at a narrow gap so as to leak externally hardly occurs. The air advances through the space into an inserted shaft so that the ink can conventiently flow out. In a pause in use, the ink in the shaft is extracted into its reservoir under guidance. Then a core rod in the reservoir is isolated together with the reservoir when the pen is in use, thereby adjustably opening or closing a communicating hole in the main shaft passing the ink to prevent excess flow due to air pressure. A rotary flexible sub cap engages within the cap to seal the pen hermetically. In this manner, even if the pen is shaken to any extent during use, no ink leaks between the main shaft and the sub shaft, as it would in a conventional pen, thereby eliminating irregular ink flow due to defects of the air, and obviating contamination of the fingers and the drawing due to droplets of ink. |
