GB496570A - Improvements in and relating to grass and like cutting machines - Google Patents

Abstract

496,570. Lawn mowers and trimmers &c. SPON, J. May 31, 1937, No. 15127. [Classes 6 (ii) and 6 (iii)] A machine for cutting grass &c. with a shearing cut comprises two sets of oppositely rotating flat knives mounted on a wheeled carriage and carried respectively by two elements of a spur nested reversing gear train comprising three coplanar elements, of which one element consists of reversing pinions engaging directly with the two end elements and mounted in a carrier held against rotation, the gear train being positioned close against the knives and the two end elements having a short common axis or spindle. The frame of the lawn-edging machine shown consists of two generally parallel bars 1 connected together by bolts 2, 3 and bent to form handles, which are provided with wooden grips 4. It is provided with a narrow side wheel 6 on a projecting spindle 5 which drives the cutter spindle 14 through a ratchet clutch and the step-up chain gearing shown. Fast on the spindle 14 is the central wheel 15 of the spur gear train for driving the cutters, pinions 16 on a fixed carrier plate 18 engaging with the wheel 15 and with an internally toothed annulus 17. The two sets of knives 20, 21 are of the shape shown, one set being fixed on the annulus 17 and the other on a plate 22 fast on the spindle 14. In a machine for mowing the surface of a lawn, the spindle 14 may be vertical and supported by an upper bearing only, one set of knives being screwed directly to the central gear-wheel 15, which may be integral with the spindle 14. In such a machine the cutters may be driven by an internal-combustion engine, having its crank-shaft coaxial with the spindle 14.