GB241808A - Improvements in mechanical pencils - Google Patents

Abstract

241,808. Alexander, A. E. (Furedy Holding Co., Inc., F.). April 24, 1925. Petted holders. - In a pencil holder of the type provided with lead-feeding mechanism, and in which one of two leads may be projected for use while the other is held retracted in the case, means are provided for effecting a partial rotation of the lead-carriers at a predetermined point in their movement to enable them to be aligned with the aperture in the point, the rotation being effected automatically during the operation of the lead-feeding mechanism. The leads 75, 76, Fig. 1, which may be of similar or different characteristics, are held in the ends of cranked rods 79, 80 the upper ends of which extend into corresponding hollow cylinders 35, 36. The cylinders are formed with oppositely-directed helical slots, the upper portion 40 of each slot being of flat pitch, while the lower portion 41 is of steep pitch. The cylinders are mounted in apertures 18, 19, Fig. 2, formed in a guidemember 11 frictionally held in the upper end of the barrel 10 and formed with longitudinal guide slots 20, 21, into which the upper ends of the rods 79, 80 extend after passing through the helical slots in the cylinders. The guide slots are formed with two offset parts 23, 24, Fig. 4, extending parallel to the axis of the member 11 and approximately corresponding in length and position to the portions 40, 41 of the helical slots in the cylinders, and the parts 23, 24 are connected by an oblique, slot 25. Pinions 45, Figs. 1 and 5, are fixed to the upper ends of the cylinders 35, 36 and are adapted to be rotated together by a ring 50 having teeth engaging with the pinions and frictionally mounted in a cap 52 rotatable on the end of the casing. The pinions are slightly larger than the apertures 18, 19 in order to prevent downward displacement of the cylinders. Rotation of the cap 52 in one direction therefore causes the rapid withdrawal of the lead 76 from the position shown in Fig. 1 due to the engagement of the end of the rod 80 in the steep part of the helical slot in the cylinder 36, and a slight feeding forward of the lead 75 due to the engagement of the rod 79 in the flat portion of the slot in the cylinder 35. When the ends of the rods 79, 80 come to the crossslots 25, they are given a slight rotation to move the cranked end of the rod 79 into, and the end of the rod 80 out of, alignment with the aperture in the detachable tip 15. Further rotation of the cap in the same direction then causes rapid advance of the lead 75 and slow retraction of the lead 76. Spare leads may be carried in apertures 30 formed in the member 11. The end of the cap 52 may be adapted to hold an eraser 87, and a covering-cap 70 may also be provided, the eraser or cap serving to close the ends of the receptacles 30 and to prevent upward movement of the cylinders 35, 36.