| 摘要 |
It is arranged that a writing lead (10) is grasped and released by reciprocation of a chuck (3) provided in a body cylinder (1) so as to inch the above-mentioned writing lead forward and a rotational drive mechanism is provided for rotationally driving a rotor (5) in one direction in conjunction with retreat operation by the writing pressure applied to the above-mentioned writing lead and forward movement by releasing the writing pressure. A pipe support member (8) for supporting a pipe end (7) is accommodated in a base (1A) which constitutes a front end portion of the above-mentioned body cylinder, and a retreat drive mechanism is provided for gradually retreating the pipe end supported by the above-mentioned pipe support member towards the above-mentioned body cylinder in conjunction with rotational drive operation of the above-mentioned rotor which constitutes the above-mentioned rotational drive mechanism. With the above-mentioned structure, a pipe-slide type mechanical pencil is provided which can maintain an amount of projection of the writing lead from the pipe end within a certain range.
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