Abstract: Grass trimmer comprising a self-propelled motorized frame with which at least one lateral cutting plate provided with at least one rotary cutting blade is associated, said at least one lateral cutting plate being associated with said frame by adjustment means able to position it in a plurality of cutting positions, in each of which said at least one rotary cutting blade lies at a predetermined distance from the longitudinal axis of said grass trimmer.

Abstract: Steering system for vehicles comprises a frame with a front axle and a rear axle, at least one of these carrying two steered wheels, the wheels of each axle being driven by a hydraulic motor via a differential unit, the steered wheels being connected, for steering control, to a cylinder-piston unit fed by a usual power steering device, in which at least the hydraulic motor associated with one axle is of variable piston displacement, and is associated with piston displacement adjustment means governed by the position of the cylinder of the cylinder-piston unit which controls the steering.

Abstract: Steering system for vehicles comprises a frame with a front axle and a rear axle, at least one of these carrying two steered wheels, the wheels of each axle being driven by a hydraulic motor via a differential unit, the steered wheels being connected, for steering control, to a cylinder-piston unit fed by a usual power steering device, in which at least the hydraulic motor associated with one axle is of variable piston displacement, and is associated with piston displacement adjustment means governed by the position of the cylinder of the cylinder-piston unit which controls the steering.

Abstract: A lawn mower includes a cutting unit having two rotors coupled together within a single casing which rotate in opposite directions. The rotors carry at least two aligned blades. The distance between the axes of the rotors is such that the areas covered by the blades when rotating are partially superposed in correspondence with an axis of symmetry of the pair of rotors which coincides with the mower axis. The direction of rotation of the two rotors is such that the direction of movement of the blades when in proximity to said axis of symmetry is the same as the forward travel direction of the mower.