KNIFE SHARPENING TOOL AND APPARATUSES FOR MAKING IT Russian patent published in 2007 - IPC B24D15/08 B24D9/00 B24D18/00 B23D19/02 

FIELD: manufacture of manual non-rotary tools for sharpening cutting edges of knives.

SUBSTANCE: knife-sharpening tool includes carcass with jacket stretched on his surface. Carcass is made of hollow closed section along generatrix of which there is split with butts elastically closed one to other. Jacket is made of grinding cloth whose lengthwise edges are placed in such a way that their working surfaces are turned outside and they are sliced one to other at forming W-shaped zig clamped between butts of said split inside carcass. Edges of jacket are overlapped relative to ends of carcass. Apparatus for making blank of carcass in the form of elongated hollow closed section along generatrix of which there is slit with elastically closed butts includes round rotating cutter, feeding and supporting members. Feeding member is in the form of lateral discs combined with rotating cutter. Supporting member is in the form of drawing roller. Apparatus for making jacket blank in the form of belt of grinding cloth having lengthwise edges turned outside by their working surfaces and mutually sliced at forming W-shaped zig with the aid of bent portions on said lengthwise edges includes members for marking lines of bending portions on working layer of grinding cloth; members for bending along said marking lines; unit for drawing belt of grinding cloth between marking and bending members. Unit for drawing grinding cloth belt is in the form of cylinder having rows of perforating needles engaging with belt, mainly along bending lines when working layer of cloth is turned inside. Apparatus for stretching jacket (grinding cloth belt) on carcass (elongated hollow closed section having slit along generatrix with mutually closing butts) includes unit of driven cams and housing for mounting unit for drawing apart elastically closing butts of said slit and unit for putting inside carcass overlapped edges of jacket. Unit for drawing apart edges of slit includes two cleats moving apart along radius; axially movable cleat and crosspieces jointly coupled with said cleats for forming transformed parallelograms. Different portions of jacket of knife sharpening tool may be used respectively for rough trimming, fine sharpening, lapping, polishing. Improved design of unit for drawing apart elastically closing butts of slit of carcass provides possibility for placing said unit in narrow internal space of carcass.

EFFECT: enhanced efficiency and quality of sharpening operations, increased drawing effort of belt and easy bending of belt along perforated lines, lowered labor consumption for stretching jacket on carcass.

11 cl, 11 dwg