GB813280A - Improvements in drive transmitting means for grinding and like machines - Google Patents

Abstract

813,280. Grinding. BLAKESLEY, L. F. [Dec. 2, 1957 [Dec. 4, 1956], No. 37021/56. Class 60. A drive means for transmitting a reciprocatory movement to the tool or work slide 4 of a grinding or like machine comprises at least one endless belt 10 which is arranged to be driven in opposite directions by a power unit 14 and rotate a toothed slide traverser 6 engaging a longitudinally-extending series of spaced abutments 5 provided on the slide. The invention is described as applied to a machine which is constructed similarly to that of Specification 626,237 for grinding rotary lawn mower cutting cylinders in which the cylinder 35 is mounted between upstanding brackets 33 on a slide 4 reciprocable on slideways 3 on a lid 2. The slide is reciprocated by a rack and pinion or, as shown, a roller chain 5 which is rigidly secured to a depending portion 4a of the slide and engages a sprocket 6 mounted on one end of a shaft 7 rotatably-disposed in the lid 2. The other end of the shaft carries a handwheel 9 and a pulley 8 connected by a linked bolt 10 to a second pulley 11 mounted on an anti-friction bearing between a flange 16 secured to a shaft 13 driven from reduction gearing 15 by an electric motor 14, and a plate 18 keyed to the shaft 13 but axially-movable by a handwheel 20 so as to releasably-clamp the pulley between itself and the flange. The slide can thus be traversed by the handwheel 9 or, with the pulley clamped to the flange, by the motor 14, The motor is supported in a U-shaped frame 22 which can be pivotted to adjust the tension in the belt. At the ends of the stroke of the slide 4, the motor is reversed and the slide traversed in the opposite direction by a manually-operated switch 25 or by one or other of switches 24, 24<SP>1</SP> co-operating with its respective switch 23, 23<SP>1</SP>. Alternatively, the direction of traverse may be reversed by gearing incorporated in the reduction gearing. During traversing, the cutting cylinder is angularly moved by a finger 37 engaging the back of the blade 36 being ground so as to maintain the blade in contact with the grinding wheel which is belt-driven from an electric motor and mounted on a bracket 27 vertically-adjustable by a handwheel 29. With the finger 37 disengaged, the cutting-cylinder can be rotated to obtain spin finishing by an electric motor 39 which is mounted on a bracket 38 on the slide 4 and belt-drives a spindle connected to the cutting-cylinder by a crank-pin engaging a radially-extending lug on a collar detachably-secured to the spindle of the cylinder.