Agricultural Header with Double Knife Cutting System

A sickle header including an elongate cutter bar along a forward edge of the sickle header, the cutter bar comprising:

• a mounting plate extending a length of the cutter bar;
• a top cutter bar assembly mounted to reciprocate in a side-to-side motion relative to a forward portion of the mounting plate, the top cutter bar assembly having an elongate top knife bar mounted on a top slide plate, the top knife bar having a row of knife sections having angularly related cutting edges;
• a bottom cutter bar assembly mounted to reciprocate in a side-to-side motion relative to the forward portion of the mounting plate, the bottom cutter bar assembly having an elongate bottom knife bar mounted on a bottom slide plate, the bottom knife bar having a row of knife sections having angularly-related cutting edges such that the oppositely facing adjacent knife sections of the top and bottom knife bars effect a cutting action which severs plant stems and stalks captured between the cutting edges as the top and bottom cutter bar assemblies are reciprocatingly moved sidewardly;
• a spring mechanism connected to the mounting plate causing a downward biasing force on the top slide plate;
• a spring mechanism connected to the mounting plate causing an upwards biasing force on the bottom slide plate such that the top and bottom cutter bar assemblies are forced toward each other separated by the mounting plate;
• and
• a sickle drive mechanism configured to drive the top and bottom cutter bar assemblies, the sickle drive mechanism having a rotatable flywheel and an upper crank mounted on a first side of the flywheel and a bottom crank mounted on a second side of the flywheel opposite the first side, wherein the upper crank drives the top cutter bar assembly such that the top slide plate slides along the mounting plate as the flywheel rotates, and the bottom crank drives the bottom cutter bar assembly such that the bottom slide plate slides along the mounting top slide plate to move the top and bottom cutter bar assemblies in opposite sideways directions.