GB1362128A - Knife sharpening device - Google Patents

Abstract

1362128 Sharpening knives ARMOUR & CO 8 Nov 1972 [8 Nov 1971] 51433/72 Heading B3D A device for sharpening a knife 100, such as a circular skinning knife having teeth used for cutting, tearing or shearing, comprises a table 30 adapted to receive the knife, magnets 41, 42 for attracting the knife to the table to hold the knife in frictional engagement therewith in position for sharpening one section of the knife, and means for moving the knife with respect to the table to present another section of the knife for sharpening. The sharpening is effected by a grinding wheel 13 which is driven by a motor 12 and periodically trued by a wheel 19 rotated by a shaft 17 and gearing 16 from a motor 15, the wheel 19 having adjusting means 21. The table 30 is carried by an arm 31 adjustable in a block 32 mounted on pivots 33 in the base 11 of the machine. The lower position of the table, n which grinding is effected, is determined by abutment with a cam 37 adjustable by a device 38. A hub 39 is provided on the table for engaging the centre hole of the knife to be sharpened, the knife being frictionally held on the table by permanent magnets 41, 42. A motor 45, controlled by a switch 46, drives, through gearing 47, a shaft 48 having three cams 49, 50, 51. Cam 49 bears against an arm on a rod 62 which is guided for longitudinal movement by rollers 63 and has a detent 65 for engaging a tooth of the knife, each rotation of the cam causing the detent to index the knife one tooth. The cam 50 bears on one end of a lever pivoted to the base, the other end of the lever acting on the under side of the table to raise the table from its grinding position determined by the cam 37 during the indexing movement. The third cam 51 acts on a pawl to rotate a ratchet wheel one tooth for each rotation of the cam, the ratchet wheel having the same number of teeth as the knife and rotating a further cam which, after one rotation, actuates a switch to stop the motor 45.