GB334742A - Improvements in mowing machines - Google Patents

Abstract

334,742. International Harvester Co., (Assignees of Pearson, C.). Dec. 5, 1928, [Convention date]. Mowing-machines. - A mower attachment is secured to the draw bar of a tractor in such a manner that should the cutter bar strike an obstruction an automatically acting release coupling becomes uncoupled and the cutter bar and mower attachment swing back as a whole to minimize the impact with the obstruction. The ends of the U-shaped draw bar 24 are pivoted in plates 23 attached to casings 18 for the gear driving the stub axles on which the wheels 15 are mounted. The bar is also supported by rods 25 adjustably hung from notched plates at the tops of the casings. A transverse bar 27 is secured at one end to the draw bar by a pivot 28 and carries a gear case 29 for a multiplying gear driven through a universal joint 53, a shaft 54, a second universal joint 55 and a splined sleeve 56 from a power take-off shaft 22 projecting from the transmission 21 of the tractor. The gear case 29 has an extension 30 including a sleeve 33 for receiving a transversely extending coupling arm 34 threaded to receive and carry pivotally a coupling yoke 38 to which the mower shoe is pivoted. The reciprocating knife 43 is driven through a pitman 45 from an eccentric wrist pin 46 on a fly-wheel 47 on the shaft of the multiplying gear. The coupling yoke 38 is also releasably connected to the tractor by a rod 57 which, at its forward end, has a lateral pin extension normally engaged in a notch in a latch plate 60 pivoted on a bracket 62 bolted to the side of the draw bar. The latch plate is normally held by springs 68 on a member 66 in such a position that the pin extension is retained in the notch, but on an obstacle being struck by the cutter bar the springs 68 yield and the rod 57 is released, permitting the complete attachment to swing backwards about the pivot 28 : the splined sleeve 56 simultaneously moves off its driving shaft, thus stopping the drive to the cutter bar. The cutter bar is rocked by a handactuated lever 76 pivoted in a bracket 70 on the bar 27 and connected by a link 74 with an upright projection 75 on the coupling yoke 38. It is lifted by a lever 89 fixed to a shaft 81 mounted in bearings in the gear case 29 and the bracket 70 and provided with a crank 84 connected to the usual lifting gear 85 - - 88 of the cutter bar. A foot lever 92 is fitted to assist the hand lever 89 and a counterbalance spring 83 is fitted to a small crank extension on the shaft 81. A guide 95 is fitted to ensure the foot lever moving clear of the tractor wheel when the mower is engaged or disengaged. A brace 97 extends across the mower attachment.