GB1499975A - Honing apparatus - Google Patents

Abstract

1499975 Honing tools BG PARSONS 7 April 1975 [7 Jan 1974] 32472/73 Heading B3D Apparatus for honing plane irons, chisels and like woodworking tools comprises a jig 8 means for holding an oil-stone 13 with a longitudinally extensive, flat honing surface 14 and for adjusting the attitude of the honing surface with respect to the jig both longitudinally and laterally, and a carrier 9 movable with respect to the jig and adapted to hold an iron or chisel blade 23 at an appropriate honing angle, the jig including two tracks 16 extending longitudinally one each side of the honing surface and at least capable of being coplanar with the surface or of lying in a plane parallel thereto and the carrier straddling the surface and supported on runners 17 engageable with each track. The body of the jig is of inverted channel section and has an aperture 12 for receiving the stone 13 which is supported by adjustable bearers 24. Gauge strips 27 can be mounted by screws 28 on the jig so that the bearers can be adjusted by nuts 26 to engage the honing surface 14 with the strips, the stone then being secured in position by end clamping screws 31. Bars 15 are mounted on each side of the body to form the tracks 16. The bars are pivotally adjustable about screws 33 at one end of the body so as to be parallel or slightly inclined to the tracks, the other end of the bars being secured to the body by screws 35 passing through oversize or elongated holes in the bars. Between the bars are strips 36 having projections 37 which act as stops for the carrier. The runners 17 have rollers or grooves engaging the tracks and are formed with bell-mouthed recesses 20 receiving trunnions 18, 19. A spindle 40 is screw threaded into the trunnion 18 and has a plain portion 41 on which a jaw 22 is rotatably mounted. The trunnion 19 is screw threaded on to the spindle and carries a jaw 21, rotation of the trunnion moving the jaws together to grip an iron or chisel to be sharpened against locating surfaces 45, secondary inclined surfaces 46, 47, one 42 of which is convex, acting to urge the iron or chisel against the locating surfaces. Further surfaces 48, 49, 50 are provided on the opposite side of the spindle 40. Auxiliary locating surfaces 51 are provided for use with mortice type chisels and plough irons. Graduations 54 are provided for use in determining the extent of projection of the chisel or iron from the jaws for a particular honing angle. In use, the chisel or iron is clamped in position between the jaws and the carrier reciprocated along the tracks with the chisel or iron engaging the stone and the tracks parallel to the surface. A curved profile may be given to a plane iron after the main honing operation by inclining first one and then the other of the tracks for a few honing strokes.