DIRECT LIQUID TYPE WRITING INSTRUMENT

摘要

PROBLEM TO BE SOLVED: To provide direct liquid type writing instruments that can strengthen a press-fit fixation state between an outer surface of a volume adjusting member and an inner surface of an ink tank, and can prevent the forward movement of the volume adjusting member even if an impact such as dropping is applied.SOLUTION: An ink reserving member 5 comprising a pen nib 2 is mounted on a front part of a barrel 3 consisting of a bottomed tubular body, and an ink tank 4 is formed in the barrel 3 at the rear of the ink reserving member 5. The ink reserving member 5 temporarily reserves overflow ink based on a pressure change in the ink tank 4. A volume adjusting member 6 for decreasing a volume of the ink tank 4 is contained in the ink tank 4, and the outer surface of the volume adjusting member 6 is press-fit and fixed in the inner surface of the ink tank 4. Multiple protrusions 61 distributed on the circumference are provided on the outer surface of the volume adjusting member 6. When the outer surface of the volume adjusting member 6 is press-fit and fixed in the inner surface of the ink tank, each of the protrusions 61 is brought into pressure contact with the inner surface of the ink tank 4.