GB1266308A - - Google Patents

Abstract

1,266,308. Pencil sharpeners. A. CHO. 30 Sept., 1970, No. 46533/70. Heading B6P. A sharpener for pencil leads 35 comprises two parts 1, 2 relatively rotatable about a common axis, the part 2 having an inner grinding surface 3, and the part 1 having a holder 5 for receiving a lead carrier 33, the holder 5 being pivotally adjustable for varying the angle to which the lead point 35 is ground when the parts 1, 2 are relatively rotated. As shown, the holder 5 has two recesses 10, 11, Fig. 2, the recess 10 being intended to rotatably receive a lead carrier 33 and the recess 11 being provided with spring- pressed jaws 23, 24 for clamping an hexagonal lead-carrier 33. The holder 5 is pivoted centrally on ball-and-socket joints 6, 7, Fig. 4, the lower ball part 7 being integral with the member 1 and the upper ball part 7 being formed on a slider 19 adjustable on the member 1 by a screw-and-slot device 20, 37 to vary the position of the holder 5 for adjusting the grinding angle. A carrier 33 placed in the recess 10 is held by the hand to prevent its rotation whilst the part 1 is rotated relatively to the part 2, the lead thus being sharpened. A carrier 33 clamped by the jaws 33 in the recess 11, cannot rotate relative to the part 1 so that relative oscillation of the parts 1, 2 causes a chisel edge to be formed on the lead 35. More than one holder 5 may be provided on the part 1. A central pin 15 fixed to the part 1 extends rotatably through the part 2 and has a groove at its lower end engaged by a spring 31, the arrangement permitting easy detachment of the part 1 from the part 2. The grinding surface 3 may be formed by applying abrasive particles to the frusto-conical inner surface of the part 2, but preferably consists of a strip of emery paper secured by a clamp 9. A brush 14 of, e.g. plush, for cleaning the sharpened leads, is rigidly secured to the part 2, and openings 27, 28, Fig. 2 are provided in the part 1 for inserting holders 33 so that the leads 35 contacts the brush. The parts 1, 2 are relatively rotated for cleaning the leads. An accessory (Fig. 6) for use in sharpening the leads of a pair of compasses, comprises an hexagonal sleeve fitting into the recess 11, and wedge members for securing in the sleeve the lead-holding chuck of the compasses. To enable the lead to be adjusted to the required length prior to grinding, a helical strip 41, Fig. 2, is provided on the outer surface of the part 1 and a scale is provided on the edge 54.