| 摘要 |
PROBLEM TO BE SOLVED: To form a ball-point pen with the capability of preventing the direct flow or counterblow of ink, in particular, preventing the direct flow of ink even in the case when a falling down accident of tip end ball occurs unexpectedly by the influence of forcible wiring or dropping impacts. SOLUTION: The ball-point pen is formed by providing a valve chamber 13 in the rear part in an axis of the coupler 3 in association with the rear end of a chip 5, and a tapered or spherical valve body receiving seal 19 is set on the rear part of the valve chamber, or a valve body 17 to be placed in close content with the valve receiving seat and a spindle-like piece being in the front part and having a small diameter part at its tip end are loosely fitted in a space communicating with the valve chamber 13 and the tip inner hole part, a contact part 5a is set on the slightly rear position of the small diameter part 18, and a stepped part 9 is formed on the front end of the tip inner hole part because of being opposed to the contact part. As such, when the tip is turned upward, the valve body means close contact with the valve body receiving seat to close the orifice, or when the tip side is turned downward, such a closed state is released, as a result, the tip end of the small diameter part is brought in contact with the back surface of a tip end ball 5a so that the tip end ball is put in close contact with the inner periphery of a ball holding part of the tip. |
