GB601187A - Knife sharpener - Google Patents

Abstract

601,187. Grinding knives. CHESTER, F. R. Oct. 22, 1945, No. 27803. [Class 60] A knife-sharpener comprises a casing 11 having a slot 11c through which the knife is inserted to lie between adjacent convolutions of a helix 14, so that as the knife is reciprocated lengthwise in the slot, the helix and its supporting-member 13 are rotated and moved axially against the action of a returning-spring 17. The member 13 is mounted on a mandrel 12 one end 12a of which is secured to the wall 11b of the casing 11, the helix 14 being retained between a flange 13a and a disc 15 fitting on a square boss 13b which is riveted over to hold the disc. The spring 17 is anchored at one end 17a to the member 13 and the other end is anchored to the cylindrical centre part of an adjustment member 18, by passing the inturned end of the spring through a hole 18b. The member 18 has radial arms 18c, extending from its centre, by which the member may be turned until the junction between the two end coils of the helix 14 is centrally disposed with the slot 11c. The member 18 is then held in this position by bending the appropriate arm 18c to lie in a hole 11d in the wall 11b. File teeth or corrugations may be provided on the operative surfaces of the helix 14. The file teeth may be arranged as small threads arranged around the wire of the helix, or on the knife sharpening side thereof only.