| 摘要 |
PROBLEM TO BE SOLVED: To control ink water head pressure in accordance with the residue of ink within an ink tank by inclining the inner wall of an ink tank so that an inner cross sectional area corresponding to an ink surface-formed position gradually enlarges toward the communication hole of an ink discharge mechanism. SOLUTION: Minute interstices are formed between a flow member 8 and the inner wall 4a of a pipe body 4, and a thin layer of high viscosity fluid 7 is formed. With the consumption of ink, as an ink surface moves to the pen tip side, the high viscosity fluid 7 and float member 8 move by following this. Herein, the inner surface 4a of the pipe body 4 is formed in a taper inclined surface gradually enlarging toward the pen tip 3 side. As ink is consumed, when the high viscosity fluid 7 and float member 8 move to the pen tip 3 side, a contact area between the high viscosity fluid 7 and the pipe inner wall 4a decreases for the increase of the pipe 4 inner diameter, so that a water head pressure of the high viscosity fluid 7 also decreases gradually. |
