| 发明名称 | Ballpoint pen tip and ballpoint pen using the same | ||
| 摘要 | A ballpoint pen tip is provided in which a curved contact surface, which has a curvature different from a curvature of the ball, is provided on the bottom wall of the ball holding chamber, and the ball is in contact with a contact part which is a part of the contact surface; and between the ball and the contact surface, a first gap is formed to extend from a side of the ink circulation hole up to the contact part such that the first gap gradually narrows from the side of the ink circulation hole, and a second gap is formed to extend from a distal side of an ink circulation groove up to the contact part such that the second gap gradually narrows from the distal side of the ink circulation groove. | ||
| 申请公布号 | US9346313(B2) | 申请公布日期 | 2016.05.24 |
| 申请号 | US201113976870 | 申请日期 | 2011.12.27 |
| 申请人 | KABUSHIKI KAISHA PILOT CORPORATION | 发明人 | Takayama Kouichi;Kajiwara Takumi |
| 分类号 | B43K7/00;B43K1/08;B43K7/10;B43K23/08 | 主分类号 | B43K7/00 |
| 代理机构 | Perkins Coie LLC | 代理人 | Perkins Coie LLC |
| 主权项 | 1. A ballpoint pen tip in which a tip end portion of a tip body, which includes a ball holding chamber configured to hold a ball, an ink circulation hole formed in a center of a bottom wall of the ball holding chamber, and a plurality of ink circulation grooves extending radially from the ink circulation hole, is caulked inside, so that a part of the ball held in the ball holding chamber projects from a tip end edge and the ball is rotatably held, wherein: a curved contact surface, in which the ball is inscribed, which has a curvature different from a curvature of the ball, is provided on the bottom wall of the ball holding chamber, and the ball is to be in contact with a contact part which is a part of the contact surface; between the ball and the contact surface, a first gap is formed to extend from a side of the ink circulation hole up to the contact part such that the first gap gradually narrows from the side of the ink circulation hole, and a second gap is formed to extend from a distal side of an ink circulation groove up to the contact part such that the second gap gradually narrows from the distal side of the ink circulation groove; and a length of an opening of the first gap on the side of the ink circulation hole is from 0.001 μm to less than 10 μm in the shaft center direction. | ||
| 地址 | JP | ||