| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an expanding and contracting type ballpoint pen in which an expanding and contracting operation can be surely performed by one hand, and it is expanded to become a writing condition only by applying a backward impact on a sliding tip metal when it is contracted. <P>SOLUTION: The expanding and contracting type ballpoint pen consists of a front shaft part 1 and a back shaft part 2 freely slidably inserted into the back part of the front shaft part and freely expanded and contracted to their mutual end part positions. The front shaft part consists of a front shaft main body 4 on which a mouthpiece 3 is screwed, a ballpoint pen refill 8 which is freely removably and tightly inserted into a core cylinder 6 internally provided in the front shaft main body through a fixed pedestal 5 and whose core tip is freely projected from the mouthpiece and the sliding tip metal 7, the sliding tip metal which is freely projected to a position concealing the core tip of the ballpoint pen refill between the step difference of the mouthpiece and a flange at the tip part position of the ballpoint refill through a first spring 9, a pushing rod 10 which is freely penetrated through the fixed pedestal provided on the base end of the core cylinder, whose tip end is brought into contact with the flange of the sliding tip metal and which is freely pushed against the first spring, and a long spring 11 which is wound on the outside of the core cylinder, whose base end is brought into contact with the fixed pedestal, and whose tip end pushes the back shaft part. <P>COPYRIGHT: (C)2007,JPO&INPIT |
