| 摘要 |
A mechanical pencil comprises a body lead retaining means movably attached to the body, and biasing means for urging the lead retaining means into an operative position in which a lead portion protrudes from the body to facilitate writing or drawing in use, wherein the retaining means is movable against the urging force of the biasing means so as to allow the lead portion to retract into the body in response to the application of excessive pressure to the lead portion in use. The pencil may comprise a tubular cylindrical tube 11; a lead containing tube 12 containing a plurality of leads and having inner and outer walls so tapered that the lead inlet 13 formed at the rear end is larger in diameter than the opposite end formed with a guide hole 14 for sequentially feeding the leads one by one thereinto. a chuck portion 16a integrally formed with the lead guide 16 attached to the lower end of the lead containing tube 12; a ferrule 17 detachably attached to the cylindrical tube 11; a clamping ring 19 so attached to the outer periphery of the chuck portion 16a as to open or close the chuck portion, and elastic members 24, 25 interposed between the lead containing tube 12 and the clamping ring 19. By tapering the walls of the lead containing tube 12, the transfer of leads from the tube 12 to the lead guide 14 is facilitated. When excess writing pressure is applied through the outer barrel 11, spring 24 is compressed, raising supporting ring 21, clamping ring 19 and chuck 16a to retract the lead 18 within ferrule 17. As a result the risk of lead breakage is minimised. <IMAGE>
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