GB1097106A - New or improved grinding machine - Google Patents

Abstract

1,097,106. Grinding. L. F. BLAKESLEY. April 22, 1966 [April 23, 1965], No. 17143/65. Heading B3D. A machine for grinding lawnmower cutting cylinders C and the like comprises means for supporting the cylinder so that it can be turned about its axis, a carriage 7 supported on a slideway 2, 3 for reciprication along a path substantially parallel to the axis, the carriage carrying a cup-form cylindrical grinding wheel rotatable about an axis perpendicular to the cylinder axis, a finger F on the carriage for abutment against successive portions of one of the spiral cutting blades of the cylinder to locate the blade relatively to the grinding wheel, and a detachable attachment for use in grinding the bottom or ledger blade of the lawnmower. The machine consists of three rods 2, 3, 4 which are secured to end plates 1 in which are mounted bosses 11 for receiving stub shafts 10 having collars 14, 15 for engaging bearings 17 on the shaft of the lawnmower cylinder, bushes 18 being provided to accommodate the various sizes of bearings and the shafts 10 being axially adjustable to correspond to the length of the cylinder. The rods 2, 3 act as slideways for the carriage 7 which has rollers 20 engaging front and rear surfaces of the rod 3, and rollers 21 engaging the rear surface only of the rod 2. The rollers are mounted on a plate 19 on which is secured a block 24 having a vertical slideway for a slide 25. A screw 33 provides for vertical adjustment of the slide which supports a structure 27 carrying a motor 28 driving the cup-shaped grinding wheel 29. A peg (35) is both vertically and horizontally adjustable on the structure and carries the finger F which is in the form of a plate 34 having two edges selectively engageable with a blade of the cylinder according to whether the helix of the blade is left or right handed. The rotation of the grinding wheel is such as to urge the blade against the finger which rotates the cylinder as the carriage is moved along the rods 2, 3. The attachment for use in grinding the ledger blade consists of a bar 39, Fig. 4, having a pair of side members 40 receivable in pairs of blocks 41, 42 on the side plates 1 to which the members are secured by screws (43). Adjusting screws 45, 49 are provided for adjusting the inclination and the parallelism of the bar relative to the rods 2, 3. The bar has a pair of vertically adjustable plates (60) for locating the front edge of the ledger blade P the shoe S of which is clamped against supports 52 by clamps 56, the supports and clamps being mounted on rods 51, 55 clamped in holes in brackets 50 extending forwardly from the bar 39. The machine may be used for sharpening milling cutters, guillotine blades, plane irons, chisels or the like.