| 摘要 |
PROBLEM TO BE SOLVED: To provide an extendable and retractable ballpoint pen capable of replacing easily a refill therefor. SOLUTION: The peripheral wall of a barrel 10 is provided with a first window part 13, permitting the entering or extracting of the ball unit 12a of a clip 12, and a second window unit 14, formed at a the rear side of the window unit 13 and not opposed to the inner surface of the clip 12, while a nock rod 30 is provided with a first projection 31a capable of engaging with or releasing out of the first window unit 13 by deflecting elastically and a second projection 32a capable of engaging with or releasing out of the second window unit 14 by deflecting elastically. By pushing operation of the nock rod 30, the second projection 32a is slid in the second window 14 to engage the first projection 31a with the rear end rim of the first window unit 13 and engage the second projection 32a with the rear end rim of the second window unit 14 when the first projection 31a is released out of the first window unit 13. |
