| 摘要 |
PROBLEM TO BE SOLVED: To provide a mechanical pencil capable of ensuring the normal rotary drive of a writing lead in writing.SOLUTION: In the mechanical pencil, a rotary drive mechanism 25 capable of converting reciprocating motion in the axial direction to rotary motion is connected via relay pipes 7 connected to a chuck 5. In a connection part between the rotary drive mechanism 25 and the relay pipes 7, a shaft hole is formed on the rotary drive mechanism 25 sides and a protruding engaging part 7a protruding toward the outer periphery side of the relay pipe is formed on the relay pipe 7 side. A peripheral part of the protruding engaging part 7a and an inner periphery of the shaft hole on the rotary drive mechanism side are connected by contact with each other so that a circular cavity 40 is formed between a peripheral lateral face of the relay pipe 7 and the shaft hole in the front side next to the protruding engaging part 7a in the axial direction. |
