Abstract:
A hybrid powertrain unit includes an internal-combustion engine, and a gearbox device with a primary shaft that can be connected to the shaft of the internal-combustion engine via a clutch device. The gearbox device includes a secondary shaft with an output pinion meshing with a first crown wheel of a differential, the casing of which is rigidly connected to the casing of the gearbox device. An electrical machine is designed to function as electric motor and as electric generator, having a shaft connected by a transmission to a second crown wheel of the differential. An engagement device driven via an electronic control actuator is set between the shaft of the electrical machine and the second crown wheel. The electrical machine can be set coaxially to the output shafts of the differential or parallel thereto. Alternatively, the shaft of the electrical machine may be connected to the shaft of the internal-combustion engine by means of a belt transmission and engagement device.
Abstract:
A gear change device for a motor vehicle has a braking member for stopping a rotation of a primary shaft before engagement of a reverse gear. The braking member includes a lever pivotally mounted on a gearbox about a separate axis with respect to axes of the primary and secondary shafts of the gear change device. The braking lever is controlled by an electrically-driven actuator by a pusher member displaceable by the actuator in a direction substantially tangential with respect to the primary shaft, towards an operative position in which it interposes with a wedge-like action between the braking lever and a fixed abutment wall, so as to press the brake pad against a cooperating part which is connected in rotation with the primary shaft.
Abstract:
A transmission includes a first primary shaft carrying driving gearwheels for odd gears and reverse, a coaxial second primary shaft carrying driving gearwheels for the even gears, and a secondary shaft carrying idle driven gearwheels meshing with the driving gearwheels. The gearbox has a gear shift device having sliding engagement sleeves each arranged to connect a driven gearwheel corresponding to a given gear for rotation with a secondary shaft. Corresponding sliding shift forks cause an engagement sleeve to slide between a neutral and shift positions. A rotary drum has grooves on its cylindrical surface in which a stud slides, and is connected for translation with a respective shift fork in its sliding direction. An actuation unit rotates the drum stepwise among angular positions corresponding to engagement sleeves' predetermined positions. In a first angular position the engagement sleeves simultaneously engage gear reverse.
Abstract:
Described herein is a gearbox for a motor vehicle including a plurality of forward gear ratios and a reverse gear ratio, the gearbox further including: a control device (configured for controlling the selection and the engagement of said forward gear ratios and of said reverse gear ratio; and a plurality of engagement devices that can be controlled by means of said control device for engaging the forward gear ratios or reverse gear ratio (RM) of the gearbox that are operatively associated to said devices. The gearbox includes a locking device, which is electrically controlled and configured for preventing actuation of the engagement device associated to a predetermined forward gear ratio, said locking device being configured for being actuated above a threshold speed of the motor vehicle on which said gearbox is installed.
Abstract:
A gear-change device includes a primary shaft, a secondary shaft, and a third shaft, which bears both a gear of the reverse and an output pinion meshing with a gear of a differential. The third shaft is connected via a gear reducer to the shaft of an electrical machine, the casing of which is rigidly connected to the easing of the gear-change device.
Abstract:
Described herein is a gearbox for a motor vehicle including a plurality of forward gear ratios and at least one reverse gear ratio, the gearbox including an electro-hydraulic actuation unit configured for selection and engagement of the gear ratios.The gearbox comprises a first hydraulic pump and a second hydraulic pump, wherein:the first hydraulic pump is driven in rotation by an electric motor and is configured for supplying hydraulic fluid taken in from a first intake environment to said electro-hydraulic actuation unit; andthe second hydraulic pump is driven in rotation by an engine of said motor vehicle and is configured for supplying hydraulic fluid taken in from a second intake environment to said gearbox, for lubrication thereof, and to said first intake environment.
Abstract:
A device for selection and engagement of the gears of a gearbox for motor vehicles has a control shaft mounted rotatable and axially movable with respect to the casing. Mounted on the shaft is a hub having an engagement finger for controlling gear engagement devices, which is configured to oscillate in the space between two fingers of a selection mask, which is mounted on the shaft axially movable therewith and is guided with respect to the casing so as not to follow rotation of the shaft and the hub when a gear is engaged. During displacement of the engagement finger towards an extreme position preliminary to the engagement of the reverse gear, the selection mask is forced to move temporarily into a rotated position, wherein it actuates one or more of the selector devices of the forward gears to enable silent engagement of the reverse gear.