| 摘要 |
A roller ball pen that permits a user to adjust the bias force that biases a roller ball cartridge out of the pen to suit the user's particular writing style. The pen has a body having distal and proximal ends, a roller ball cartridge disposed in the body, a cap removably disposed on the proximal end of the body, a nut slidingly disposed in the cap, a spring attached to the distal side of the nut and abutting the roller ball cartridge, and a drive rod engaged with the nut. Rotation of the drive rod moves the nut distally or proximally, thereby adjusting the bias force applied by the spring to the roller ball cartridge. |
