Mechanical pencil structure and writing instrument having the mechanical pencil structure

摘要

PROBLEM TO BE SOLVED: To prevent an operational failure due to an operation of detachment and attachment of a front-side detachable part.SOLUTION: A mechanical pencil structure includes: a lead core delivery mechanism 10 delivering a lead core X pinched by a pinching part 12 inside a cylindrical part 11 forward of the cylindrical part 11; and the front-side detachable part attached to the cylindrical part 11 so as to be separable forward relative to the cylindrical part. A hard annular projection 11a1 adjacent to or coming into contact with an outer peripheral surface of the lead core X pinched by a pinching part 12 is provided on a forward side relative to the pinching part 12 in the cylindrical part 11.SELECTED DRAWING: Figure 3