| 摘要 |
PROBLEM TO BE SOLVED: To provide an upward writable ball-point pen which enables writing even when turned upward. SOLUTION: An air hole (3) is formed in a cylinder (2) connected to the ball-point pen (1), and a rubber film (4) is also fitted to the cylinder (2). A piston (5) is loosely inserted together with the rubber film (4) into the cylinder (2) while the air hole (3) is closed, and compressed air produced in the cylinder (2) is made to work on the ball-point pen (1). |
