Automated Manual Transmissions (AMTS) are increasingly more common in modern motor vehicles provided with internal combustion engines. An AMT is an automation device which operates on the traditional manual gearbox by opening and closing the clutch, by selecting, engaging and disengaging the gears by means of respective actuators. These controls are electronically actuated by a transmission control unit, and by operating on the manual gearbox of a motor vehicle as a driver would, this actuation allows the driver to shift gear either automatically or sequentially without using the clutch.
Specifically, an electro-actuated manual transmission comprises an electro-actuated clutch, which is in turn provided with a known clutch mechanism, with an electric actuator for actuating the clutch mechanism and with a mechanical transmission, which is interposed between the electric motor and the clutch mechanism for transmitting the motion.
As known, the clutch mechanism is provided with a basket which accommodates a clutch plates pack therein, the plates being coupled to the basket by means of one or more springs. The control of the electric motor allows to move the clutch mechanism between a closing position (or retracted resting position), in which the clutch plate pack is pressed to allow the transmission of a driving torque, and an opening position (or advanced operating position).
As time goes by, and as the kilometers covered by the motor vehicle increase, the clutch plate pack tends to be worn and consumed, thus also determining a displacement of the closing and opening positions of the clutch mechanism.
In order to ensure that the closing position of the clutch mechanism does not vary from the point of view of the transmission control unit, a hydraulic or mechanical compensating device needs to be inserted into the mechanical transmission to recover the wear of the clutch plate pack; however, the insertion of a compensating device has the drawback of considerably increasing production costs, assembly time and overall volume of the electro-actuated clutch.