| 摘要 |
PURPOSE: To assuredly maintain a valve opening operation for a long time by mounting an elastic member which pushes back a cap to a regular mounting position by releasing a push after the cap is pushed in up to a vicinity of a cap mounting base end. CONSTITUTION: A cap 4 is pushed in up to a vicinity of a cap inserting base end 3-1 at a head end opening 3 of a writing tool and mounted. An inner bottom 4-1 of the cap 4 butts against a rotary body 5 protruding from a head end of a tip 2 so as to retract the rotary body 5 toward the inner part of the tip 2 so as to separate it from an inward head end edge 2-1 of the tip 2 against a spring 6. The head end of the tip 2 is opened and a compressed air in the cap 4 compressed in the push-in mounting process of the cap 4 is sent into a liquid tank 1 so as to raise the internal pressure of the liquid tank 1. After the cap 4 is mounted in the cap mounting base end 3-1 of the head end opening 3 by pushing it up to the vicinity of the mounting base end 3-1, the push is released, and the cap 4 is automatically pushed back to a regular mounting position at the head end opening 3 by an O-ring 7. |
