Patent ID: 7121074

Claim:
In a harvester, the improvement comprising: a reciprocable sickle; and a counterbalancing epicyclic drive operably coupled with said sickle for reciprocating the same, said drive including: a main shaft rotatable about a first axis; a first counterbalance weight rotatable with said main shaft about said first axis; a crankshaft orbital about said first axis of rotation and rotatable about a second axis, said crankshaft being disposed to rotate in a direction opposite to the direction of rotation of the main shaft as the crankshaft orbits about said first axis; a second counterbalance weight rotatable with said crankshaft about said second axis; and a drive stud operably coupled with said crankshaft in offset relationship with said second axis, said sickle being operably coupled with said drive stud, said first counterbalance weight being heavier than the second counterbalance weight by an amount that compensates for the eccentric relationship between said first and second axes.