| 摘要 |
PROBLEM TO BE SOLVED: To improve opening/closing operability, sealability, a use feeling and so on.SOLUTION: A barrel 10 includes a body part 12 protruding a writing part 11 forward and a cylindrical holding part 13 formed thinner than the body part 12 and protruded forward from the body part 12 to hold the outer periphery of the writing part 11 in a cylindrical form. A cap 20 has an outer cylinder 21 pivoted to the body part 12 and an inner cylinder 22 arranged inside the outer cylinder 21. A circular motion in one direction engages the inner cylinder 22 with the cylindrical holding part 13 from the front side and brings the outer cylinder 21 into contact with the body part 12, and a circular motion in the reverse direction separates the inner cylinder 22 from the body part 12 and the cylindrical holding part 13. The position in the axial direction of the barrel at which the inner cylinder 22 is engaged in the cylindrical holding part 13 corresponds to the position of the pivoting part 12c, and the position in the axial direction of the barrel at which the outer cylinder 21 comes into contact with the body part 12 is located on the rear side to the position of the pivoting part 12c. |
