| 摘要 |
PURPOSE:To obtain a ballpoint pen that can be used for writing in an upward posture, and prevents occurrence of a reverse flow of ink. CONSTITUTION:A ball valve support claw 2 is so provided in a base end part of a tip 1 with a ball (b) at the tip part thereof as to be lanced toward the center part thereof. A valve chamber 4 is formed in the base end of a mouthpiece 3 into which the tip 1 is fitted. A ball valve receiving part 6 having a first ink supply path 5 smaller in diameter than a ball valve 7 is formed in the base end part of a mouthpiece 3. The ball valve 7 is loosely fitted in the valve chamber 4 so as to float between the ball valve support claw 2 and the ball valve receiving part 6. An ink junction chamber 9 larger in diameter than the valve chamber 4 is formed in the inner top part of an ink containing body 8 into which the mouthpiece 3 is fitted. An ink holding wall 10 with a second ink supply path 11 is provided in the base end part of the ink junction chamber 9 so as to be projected inward. |
