Combine harvester with secondary cutter

Abstract From the Canadian patent

A conventional header of a combine is modified by the addition of a second sickle knife positioned rearwardly of the pan of the header. The second sickle knife is mounted on a bar which is connected to a pair of arms extending under the pan to a forward end pivotally mounted just behind the conventional sickle knife of the header. The arms and the second sickle knife can thus pivot upwardly and downwardly and are mounted on suspension springs carried on the frame of the header. A simple drive from the conventional shaft of the header is connected through a belt to a drive wobble box carried on the second sickle knife at a position part way along its length.