The present invention relates to an assembly which includes: a chassis for a mobile land vehicle, in particular an agricultural or public works vehicle; at least two half-crossmembers (21) mounted telescopically on the chassis; wheel mountings (27) pivotably mounted on each one of said half-crossmembers; steered wheels rotatably mounted on said mountings; and a device for controlling the direction of the wheels. The assembly is characterized in that it includes means (39, 41, 47) designed, for a certain position of two half-crossmembers, to increase, upon the pivoting of the wheels, the opening of the said wheels relative to the opening of the wheels resulting from the same pivoting and another position of the two half-crossmembers.

The present invention relates to a turn system actuated by hydraulic cylinders, applied to the four wheels of sugar-cane harvesters, wherein the harvester (80) comprises a rear axle (23) and a front axle (24), with wheel assemblies (9) associated to the axles (23, 24), wherein the rear axle (23) and the front axle (24) have a turn system, the one of the rear axle (23) being actuated by means of a double-action rear hydraulic cylinder (1) and that of the front axle (24) being actuated by means of a double-action front hydraulic cylinder (11), the hydraulic cylinders (1, 11) receiving a flow of oil through at least one flow divider (61) connected to an ortibrol (65) actuated by means of a steering wheel (60) of the harvester (80), the flow of oil received by the flow divider (61) being proportional to a factor related to the turn of the steering wheel (60), the turn system enabling the turn of the wheel assemblies (9) in amplitude ranging from 0.5 to 40 degrees, to the right or to the left, with respect to the longitudinal axis of the harvester (80).

The present invention relates to a turn system actuated by hydraulic cylinders, applied to the four wheels of sugar-cane harvesters, wherein the harvester (80) comprises a rear axle (23) and a front axle (24), with wheel assemblies (9) associated to the axles (23, 24), wherein the rear axle (23) and the front axle (24) have a turn system, the one of the rear axle (23) being actuated by means of a double-action rear hydraulic cylinder (1) and that of the front axle (24) being actuated by means of a double-action front hydraulic cylinder (11), the hydraulic cylinders (1, 11) receiving a flow of oil through at least one flow divider (61) connected to an ortibrol (65) actuated by means of a steering wheel (60) of the harvester (80), the flow of oil received by the flow divider (61) being proportional to a factor related to the turn of the steering wheel (60), the turn system enabling the turn of the wheel assemblies (9) in amplitude ranging from 0.5 to 40 degrees, to the right or to the left, with respect to the longitudinal axis of the harvester (80).