PURPOSE: To surely extrude a short lead for a propelling pencil even when the diameter of the lead is fine by specifying the maximum curved rate from both ends of the lead and angle of the end face of the lead and forming the lead for the propelling pencil. ;CONSTITUTION: For example, the curved rate L of the maximum curved part 1C from the both ends 1A, 1B of a lead 1 having 0.3mm outside diameter for a propelling pencil is regulated to ≤0.2mm. Moreover the angles Q of end faces 1A, 1B are regulated to 90 410 and below. In order to more exhibit effect, it is preferable that the maximum curved rate is regulated to ≤0.1mm and the angles of the end faces are regulated to 90°±4°. When the lead is held by a chuck to perform taking notes and the lead being used is consumed and becomes a short lead incapable of being used, the following lead is fed by the chuck. Thereby the rear end of the short lead is pushed out by the tip of the following lead. At this time, since the tip of the following lead does not cross the rear end of the short lead but surely coincides therewith, the short lead is surely extruded.;COPYRIGHT: (C)1993,JPO&Japio
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