| 摘要 |
PROBLEM TO BE SOLVED: To generate a metallic butting noise without applying a large impact to a writing instrument at the time of fitting a cap. SOLUTION: A cap is engaged with a writing instrument main body by making an annular protrusion 31 formed on a metal cap 3 at the end of the writing instrument overriding an engagement protrusion 71 formed on a synthetic resin inner cylinder 7 disposed on an outer cylinder 6 of the cap in the constitution of a system when the cap B is set on a writing instrument main body A. In that case, a metal ring 8 is fitted to be movable slightly accompanying a small slide resistance on a site closer to the tail end side than the engagement protrusion 71 of the inner cylinder 8 of the cap, and the cap 3 is butted into the metal ring 8 when the annular protrusion 3 overrides the engagement protrusion 71. |
