Patent ID: 6996961

Claim:
In a machine for conditioning crop materials, the improvement comprising: a front pair of mutually oppositely rotatable, non-compressible surface rolls adapted to receive a stream of crop materials, condition the materials as they pass between the rolls, and feed the materials rearwardly, each of said front rolls being provided with a set of generally radially outwardly projecting; elongated ribs extending generally helically lengthwise of the roll, the ribs of one front roll being adapted to intermesh with the ribs of the other front roll; a rear pair of mutually oppositely rotatable, compressible surface rolls disposed to receive crop materials from the front rolls and subject the crop to a further conditioning action, each of said rear rolls being provided with a set of generally radially outwardly projecting, elongated bars extending generally helically lengthwise of the roll, the bars of one rear roll being adapted to intermesh with the bars of the other rear roll, the rolls of each pair of rolls being relatively movable toward and away from one another; and tension mechanism operably coupled with the front and rear pairs of rolls in a manner to resist said relative movement of the rolls of each pair away from one another, said tension mechanism including hydraulic cylinders connected in a hydraulic circuit.