| 摘要 |
PROBLEM TO BE SOLVED: To deliver a lead without changing the grip of a shaft cylinder each time by pressing the upper surface of a side button to be inserted in a recess, causing the tip-end to come in touch with the inclined surface of a cam part of sliding pieces, and advancing the mechanical pencil writing implements on a straight line in association with the advance of the sliding pieces for delivering the lead. SOLUTION: Each insertion hole is provided on cylindrical parts 16a 16b in front of sliding pieces 14a, 14b, and the rear ends of mechanical pencil writing implements 20a, 20b are detachably secured in each insertion hole, and then cam grooves 15a, 15b are formed on the rearward inner surface sides of the cylindrical part 16a, 16b for the front and rear movement of the sliding pieces through pressure of projections 6a, 6b caused by rotation of a rotating shaft 4. Also, on the outer peripheries of the sliding pieces 14a, 14b, grooves 27a, 27b are formed to be engaged for rotative prevention with guiding ribs 2 of a rear shaft 1. Thus, the grooves 27a, 27b provided at each side surface of the sliding pieces 14a, 14b come in engagement with the guiding ribs 2 respectively, thereby causing the sliding pieces 14a, 14b to moving forward and rearward smoothly to deliver lead. |
