GB1263409A - Improvements in or relating to an arrangement for controlling the height of the cutter of a harvesting machine - Google Patents

Abstract

1,263,409. Combine harvester. KOMBINAT FORTSCHRITT LANDMASCHINE VEB. 15 May, 1970, No. 23586/70. Heading A1F. An arrangement for automatically and manually adjusting the elevator and header height in a combine harvester in response to ground contour variations comprises a header 6 having one or more ground contour sensing tracers 7 pivotally attached to the header 6 at 3, the movement of which relative to the header is transmitted via lever 4 and rope 5 to a transfer lever 8 pivotally supported in a bearing. Springs 9 and 11 provide a restoring force for the tracers 7. Lever 8 also contacts the push rod 20 of contact switch 16 whose base 17 is slidable in guides 19 attached to the machine, the contact being urged by springs 25, the force of which is adjustably counteracted by the displacement of lever 22 settable in a catch bar 24 acting through Bowden cable 21. The predetermined cutting height is set by adjusting lever 22. In operation upward or downward movement of tracers 1 causes switch 16 to actuate. Solenoid valves 34, 35 which cause a change in hydraulic pressure in ram 38, so raising or lowering respectively, the header and elevator. Limit switch 26 breaks the 'raise' circuit when the elevator 18 has reached its upper permitted height. The automatic control can be over ridden at any time by quadic polar switches 31, 32 which raise or lower the header providing semi-automatic control, and switch 33 which cuts out switch 16 and limit switch 26 to give full manual control. A securing lever 15 pivots and locks each tracer up under the header during transport.