Writing implement

Claim 1

A writing implement comprising: an outer casing having a converging lower end which is provided with a plurality of depressions near the top of the converging lower end; a coil spring disposed within the outer casing, the coil spring having a free end and the other end being formed into a lead-pushing member comprising a straight wire, the lower end of the coil spring engaging the depressions provided near the converging lower end of the outer casing; an inner tube inserted into the outer casing and through the coil spring, the inner tube having an inside channel for storing a plurality of presharpened leads therein, the lowermost end of the inner tube being formed into conical clamp portions having two diametrically opposed slots extending from the lower open end and along the longitudinal axis of the inner tube, the slots having different lengths, the first slot being about 1/2 the length of a presharpened pencil lead, the second slot being about four to six times the length of the first slot, the end wall at the closed end of the second slot being slanted, the wall slanting upwardly toward the upper end of the inner tube, the inside diameter of the inner tube being reduced at the lowermost end by an amount sufficient to frictionally withhold the leads therein, a first set of protrusions being disposed near the upper end of the inner tube to press against the inner surface of the upper end of the outer casing, the upper end of the outer casing being pressed in a convergent manner after the inner tube and the coil spring have been inserted into the outer casing, a second set of protrusions disposed at a distance of from about 1/3 to 1/2 the length of the inner tube; and a capping member adapted for covering the upper ends of the outer casing and inner tube.