| 摘要 |
PROBLEM TO BE SOLVED: To obtain the overall length of a writing instrument with simple structure at low cost, and satisfied usage and portability by securing a refill stopper to a cylinder cam in order for the refill insertion hole of the cylinder cam to be set in an open and close state as a sliding piece stays at the rearmost side. SOLUTION: As the mouth ring 6d of an automatic pencil writing body 6 is in a state projected from an opening 1a, the refill insertion hole of a sliding piece 4 opposes at the apex of the slant surface of a cylinder cam 3, so that a built-in refill never leaks even when its tip axial side is set upward. Since an interstice between the rear end of the refill insertion hole 4e and the apex of the slant surface or an interstice defined at the sliding process of the sliding piece 4 is set as small as possible, the rear end of the built-in refill springs out of the rear end into a state to be in contact with the slant surface; however, it does not suffer from leakage or damage of the refill. Also, when the tip end of a ball-point pen writing body 7a projects from the opening 1 and a mechanical pencil writing body 6 is in an accommodated state, the tip end of a projection piece is substantially flush with the front end of the refill insertion hole for closure, as a result, the built-in refill never leaks therefrom. |
