| 摘要 |
PROBLEM TO BE SOLVED: To provide a dual writing utensil wherein a coil spring of a low unit price, which is used for a ball-point pen body, can be used, and a knocking operation is prevented from being performed by mistake when the writing distal end of other writing utensil excepting a mechanical pencil body protrudes from the distal end opening. SOLUTION: When the writing distal end of other writing utensil excepting the mechanical pencil body protrudes from the distal end opening, a longitudinal movement of the rear barrel to the front barrel becomes impossible by a means. When the writing distal end of the mechanical pencil body protrudes from the distal end opening, the longitudinal movement of the rear barrel to the front barrel in order to feed a lead becomes possible by the means. Then, such a means is constituted of a protruding section which is provided on the internal surface of the rear barrel and the upper section of the sliding cylinder. |
