GB274997A - Improvements in pencil holders - Google Patents

Abstract

274,997. Barberon, P. June 18, 1926. Pencil holders.-In a pencil holder, the leadpropelling mechanism consists of one or more endless screws disposed parallel to the lead and engaging it at a number of points so that it is frictionally secured in position. The lead 4, Fig. 1, is engaged by a worm 6<a> mounted between parts 2<1>, 2" of an inner tube 2 fitting tightly within the outer shell 1, and the worm 6a can be rotated by turning the head 8 of a rotary inner tube 7 provided with a bevel or spur gear 12 engaged internally by a pinion p on the worm shaft. The tube 7 may serve as a lead magazine. A second worm may be mounted in engagement with the gear 12 diametrically opposite the first worm. In the modification shown in Fig. 3, the worm 6<a> is mounted in parts 21, 22 on a slidable lead-guide 20 which can be pressed inwards to project the lead. The gear 12 is on a short sliding tube 7 provided on its upper edge with oblique teeth 28 for engagement with corresponding teeth 30 on another short tube 29 which is under the action of a spring 33 and is guided by helicoidal or inclined slots 32 to give a rotary movement. The shape of the teeth 28, 30 is such that on the inward movement the teeth slide relatively to one another, but on the return movement under the influence of the spring 33, rotation of the tube 29 is communicated to the worm.