Abstract: A gear change for an industrial vehicle, provided with an integrated control unit housed in a seat of the gear box and comprising a plurality of actuators for controlling the selection and coupling of the gears, a plurality of electrovalves for the actuation of the actuators and a sensor of the angular speed of an input shaft of the gear change.

Abstract: A gear change for a vehicle comprising an external box made from an aluminum alloy, a main group, a driving shaft of which is adapted to be driven by an engine of the vehicle and a driven shaft of which may be drivingly connected with the driving shaft via a plurality of pairs of gears defining different transmission ratios, and an auxiliary epicyclic group connected in cascade with the main group in which the driven shaft is loaded axially by an elastic member which maintains it in contact with an axial abutment elements to ensure its correct axial positioning upon variations in play due to differential thermal expansion with respect to the box.

Abstract: A power unit assembly comprising an internal-combustion engine, a mechanical, unsynchronized gearbox, a clutch interposed between the engine and the gearbox, an inertia brake in which the gearbox, the relevant synchronization by means of the engine or the inertia brake and the control of the injection pump for the engine are controlled by an electronic processor adapted to inhibit the engagement of gear ratios to which an engine speed corresponds which does not fall within a programmed range of normal values; the processor is adapted to detect emergency operating conditions and, in such a case, to allow the engagement of a gear ratio which results in an engine speed value above said programmed range of values; to ensure synchronization even under such conditions the injection pump is provided with adjustment means adapted to allow speeds to be attained which are close to the upper limit of mechanical integrity of the engine.

Abstract: A system for automatically controlling a motor vehicle drive unit, which system comprises a hydraulic actuating unit for actuating a control member controlling selection and engagement of the gears on the vehicle transmission; a hydraulic actuator for actuating a control member controlling the clutch; and an electronic control system for processing input signals relative to operating parameters of the drive unit and vehicle in general, and for controlling the actuators to varying degrees of automation. In particular, the control system produces variable control signals for respective porportional solenoid valves controlling the actuators, so as to vary hydraulic supply to the actuators and consequently the actuating force of the same, for simulating operation by a skilled driver; the aforementioned control system also providing, when shifting gear, for controlling the speed of the engine so as to minimize slippage of the clutch.