DRAWING DEVICE FOR USE IN A DRAFTING MACHINE AND DRAWING PENCIL USED THEREWITH

摘要

A drawing device for use in a drafting machine has a base movable to any desired position; at least one drawing pencil fixedly secured to the base through a holder unit fixed to the latter; a driving arrangement capable of moving part of the drawing pencil longitudinally thereof relative to the base, and a stopper adapted to limit the upward movement of movable component parts of the drawing pencil. The drawing pencil comprises a casing having a lead guide fixedly secured to the leading end thereof; a pipe member slidably mounted in the casing, and having a chuck ring fixedly secured to the lower end thereof, said pipe member having a sleeve tightly fitted and fixedly secured to the outer peripheral surface of the upper part thereof, said sleeve being connected to the driving arrangement; and a lead stock having a space for lead stock formed in the upper part thereof and also having a lead chuck fixedly secured to the lower end thereof so as to achieve lead holding function in cooperation with the chuck ring, said lead stock being slidably mounted in the pipe member. Further, the lead guide has a lead holder bushing which gives a lead holding force more than that afforded by the lead chuck and which is movable vertically within a predetermined extent.