ALEXANDRIA, Va., June 5 -- United States Patent no. 12,275,271, issued on April 15, was assigned to MITSUBISHI PENCIL COMPANY Ltd. (Tokyo).
"Ballpoint pen refill and ballpoint pen" was invented by Yuichiro Homma (Shinagawa-ku, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "Provided is a ballpoint pen refill including: an ink storage tube made of a synthetic resin and storing an ink thereinside; a ball holder made of a synthetic resin and attached to a distal end of the ink storage tube; a ball pressing rod mounted inside the ball holder; and a writing ball stored in a distal end of the ball holder and having a rear end side held by the ball pressing rod, in which the ball pressing rod includes: a fixin...