| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a liquid direct charging type writing utensil, in which ink is fully prevented from blowing outside even under the state that a cap is removed within an aeroplane with a low pressure or the like. <P>SOLUTION: Within an ink tank 3, a partition wall part 6 for partitioning the ink tank 3 ahead and behind. A small space 31 is provided ahead of the partition wall part 6 and a large space 32 is provided behind the partition wall part 6. On the rear surface of the partition wall part 6, a tubular part 7, which projects to the large space 32 side, is provided. A large diametral hole 8 communicating the small pace 31 with the large pace 32 is provided within the tubular part 7. In the partition wall part 6 except the tubular part 7, a small diametral hole 9, which communicates the small space 31 with the large space 32 and the cross-sectional area of which is smaller than that of the large diametral hole 8. A ratio (S1/S2) of the cross-sectional area S1 of the large diametral hole 8 to the cross-sectional area S2 of the small diametral hole 9 is set in the range of 3-30. <P>COPYRIGHT: (C)2004,JPO |
