| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a retractable mechanical pencil configured so that a lead 6 can be always protruded by a length set by a user when the pencil is set from a carrying state to a writing state by protruding a nib member 8. <P>SOLUTION: A chuck 1 built in an inner shaft 7 is energized backward in a longitudinal direction by a chuck spring 5 so that the chuck 1 is movable cooperatively with a lead tank 2 in the longitudinal direction. The inner shaft 7 is energized backward in the longitudinal direction by a return spring 19 having an installation load larger than that of the chuck spring 5. When the nib member 8 provided at a front portion of the inner shaft 7 is retracted into a tip shaft 10, the backward movement of the lead tank 2 is regulated, and the chuck 1 is expanded to release the lead 6. Further, the tip shaft 10 is provided at a front portion of a shaft cylinder so as to be properly movable in the longitudinal direction. Thus, the distance from the tip of the nib member 8 to the tip of the tip shaft 10 when the nib member 8 is retracted in the shaft cylinder can be adjusted by moving the tip shaft 10 forward and backward. <P>COPYRIGHT: (C)2012,JPO&INPIT |
