GB1258418A - - Google Patents

Abstract

1,258,418. Mowing machines. C. VAN DER LELY N.V. 31 Dec., 1968 [4 Jan., 1968; 6 June, 1968], No. 61937/68. Heading A1F. Rotary mowing-machines are fitted with spring steel blades having a thickness not greater than 3 mm. for increased resistance to breakage and damage. A mowing-machine (Fig. 1) comprises at least two drums 5 rotating about vertical shafts 4 on a beam 3 connected to a beam 2 which is turnable between the limbs of a bracket 14 about a horizontal shaft 13. The bracket 14 is attached to a coupling member 15 connected to the threepoint linkage of a tractor 16, and the drums 5 are driven from the tractor by way of double pulleys 26, 28, gearbox 16A and pulleys 20, 22, (23), 25. Each drum has six oblong blades 7 held by pins 9 and stops 10, or alternatively trapezoidal blades held by two pins. At the end. of the beam 3 is a support 31 which engages the ground during operation. The machine of the second embodiment (Figs. 5, 6) comprises a hollow beam 47 which contains a series of blades 49 driven by pinions 48 A-J, 46A-J from bevel pinions 41, 42 in the driving mechanism 39 which receives power from the tractor by way of a telescopic shaft 45 and pulleys 40. The hollow beam 47 has a portion 53 which engages the ground and is pivotable on a shaft 52 allowing the machine to be raised by chains 50, 51 for transport purposes. Each blade 49 is individually attached to a portion 68 of a shaft 58 and held in place by a circlip 62 and seal 63, the blade being covered by a hood 64. The blades can also be secured to the shaft 58 by means of a compression spring 66 and a nut 65, so that the blade can deflect upwardly upon striking a hard obstacle, in addition to the blade's inherent resilience. Alternatively the cutting elements may be of a plastics material having a blade embedded, or slidably carried, in it. A further embodiment of the cutting element (Fig. 12) comprises two spiral blades 72, 73 which give resilient deflection in almost any direction.