A knife drive assembly for use in a harvesting header may be mounted near the center line of the cutter bar of the header. Mechanical power from the power unit behind the header (typically the combine power output shaft) may be translated for application to two knife assembly sections in the cutter bar at the front of the cutter table. Movement of the two knife assembly sections with this apparatus can be fully synchronized and 180 degrees out of phase, to maximize cutting effectiveness and minimize vibration of the header. The unitary drive assembly may allow for rapid repair and manufacture, and the size and weight of the knife drive assembly may represent a significant weight and balance advantage over the prior art.

A combine header includes a header frame and a set of reciprocating knives. The combine header includes a driveline for driving reciprocating movement of the knives, the driveline including a transverse drive shaft, a bevel gearbox, a lateral drive shaft, and a transmission near the knives. The lateral drive shaft is coupled respectively to the bevel gearbox and the transmission by first and second universal joints. An inlet axle of the transmission is integral with or fixed to a flywheel configured to stabilize rotation of the lateral drive shaft. The second universal joint includes two orthogonal forks coupled by a cross-piece. One of the forks is integral with or fixed to a flange that is attached to a surface of the flywheel that faces the lateral drive shaft. The flange is configured to contribute to the stabilizing function of the flywheel when the flange is attached to the surface.

A combine header includes a header frame and a set of reciprocating knives. The combine header includes a driveline for driving reciprocating movement of the knives, the driveline including a transverse drive shaft, a bevel gearbox, a lateral drive shaft, and a transmission near the knives. The lateral drive shaft is coupled respectively to the bevel gearbox and the transmission by first and second universal joints. An inlet axle of the transmission is integral with or fixed to a flywheel configured to stabilize rotation of the lateral drive shaft. The second universal joint includes two orthogonal forks coupled by a cross-piece. One of the forks is integral with or fixed to a flange that is attached to a surface of the flywheel that faces the lateral drive shaft. The flange is configured to contribute to the stabilizing function of the flywheel when the flange is attached to the surface.