| 摘要 |
PROBLEM TO BE SOLVED: To provide a writing utensil that facilitates screw fitting between a shaft tube and an ink cartridge of the writing utensil and ensures fastening with a simple constitution.SOLUTION: The writing utensil includes a shaft tube 1 having a front end to which a pen core is attached and covered with a cap 3, and an ink cartridge 4 inserted from the insertion hole 11 arranged at the rear end of the shaft tube 1 and detachably screw-fitted into the shaft tube 1. The rear end 44 of the ink cartridge 4 is accommodated inside the inserting hole 11 when the ink cartridge 4 is screw-fitted into the shaft tube 1. An engaging part is arranged in the inner peripheral face of the cap 3. The engaged part 41 is arranged in the rear outer peripheral face of the ink cartridge 4. The side face of the engaging part and the side face of the engaged part 41 are engaged and turned, thereby the ink cartridge 4 can be attached to and detached from the shaft tube 1. |
