| 摘要 |
PROBLEM TO BE SOLVED: To form a structure in which the air is easily vented by forming a rear side of a coiled spring to be seated in a coiled state, and forming an air venting passage at a stepped holding portion protruding inward to hold the spring. SOLUTION: A tip body 2 is engaged with an engaging hole 11 formed at a front end of a tip body holder 10. A holding portion 13 of a stepped coiled spring 8 to communicate the hole 11 with an ink flow passage 12 is provided. The spring 8 is held at its rear end 8a in contact with the portion 13, urged forward and charged in the body 2 and the holder 10. An air venting passage 15 of a groove state and extended in an axially central direction is provided in the portion 13. In the case of manufacturing the ballpoint pen refill 1, the refill 1 is mounted in a centrifugal machine. In this case, since the air stored in the body 2 is moved into an ink containing tube 14 through the passage 15 even when the spring 8 is charged, the air is easily vented. |
