| 摘要 |
PURPOSE:To enable alternate protruding and retracting operations of refills to be smoothly performed, by a construction wherein cam surfaces provided on sliders connected integrally to rear ends of first and second refills are selectively pressed against a cam-engaging protrusion provided on the inner periphery of a rear outer tube. CONSTITUTION:When a rear outer tube is rotated in one direction in the condition where a mechanical pencil shaft and a ball-point pen shaft are retracted and contained in a front outer tube, a cam-engaging protrusion integral with the rear outer tube pushes, for example, a cam surface of a slider on the side of the mechanical pencil shaft, resulting in a forward sliding motion, whereby the mechanical pencil shaft is protruded from the front outer tube. Then, the cam-engaging protrusion is engaged with a rear lock part of the cam surface, whereby the mechanical pencil shaft is held in a writing condition, and when the rear outer tube is knocked, a point-feeding operation is carried out. With the rear outer tube rotated in the reverse direction in this condition, the protrusion in disengaged from the rear lock part, and the mechanical pencil shaft is retracted and contained. With the rear outer tube rotated in the reverse direction in this condition, a ball-point pen shaft system is operated in the same manner as the above-mentioned mechanical pencil shaft system. |
