Mechanical Pencil

摘要

A mechanical pencil is provided including a tubular shaft, a chuck unit movably arranged in the shaft, a front rotary element adapted to be moved rearward as the unit is moved rearward, a rear rotary element adapted to be moved rearward as the front rotary element is moved rearward, a conversion means for causing the rear rotary element to rotate in a normal rotational direction as the rear rotary element is moved rearward and allowing the rear rotary element to rotate in a reverse rotational direction as the rear rotary element is moved forward, a normal directional rotation transmitting means for allowing the front rotary element to be rotated in the normal rotational direction and the rear rotary element to be idly rotated, and a reverse directional rotation restricting mechanism allowing the normal directional rotation of the front rotary element but preventing the reverse directional rotation of the front rotary element.

主权项

1. A mechanical pencil comprising:
a tubular shaft; a chuck unit for releasably holding a writing lead; the chuck unit being movably arranged in the tubular shaft; a front rotary element provided in the tubular shaft; a rear rotary element provided in the tubular shaft so as to be disposed rearward of the front rotary element; the chuck unit being movably arranged in the tubular shaft so as to be inserted through the rear rotary element and the front rotary element; the front rotary element being adapted to be moved rearward according to rearward movement of the chuck unit; the rear rotary element being adapted to be moved rearward according to rearward movement of the front rotary element; a conversion means for causing the rear rotary element to be rotated in a normal rotational direction as the rear rotary element is moved rearward and for causing the rear rotary element to be rotated in a reverse rotational direction opposite the normal rotational direction as the rear rotary element is moved forward; a normal directional rotation transmitting means for allowing the front rotary element to be rotated in the normal rotational direction as the rear rotary element is rotated in the normal rotational direction and for causing the rear rotary element to be idly rotated with respect to the front rotary element at a time of reverse directional rotation of the rear rotary element; and a reverse directional rotation restricting means for allowing normal directional rotation of the front rotary element but preventing reverse directional rotation of the front rotary element.