Abstract:
The hybrid propulsion system for an internal combustion engine having a mechanical gearbox and an electric machine. A gear shift device includes a plurality of sliding engagement sleeves, each arranged to connect a driven gearwheel for rotation with the respective secondary shaft, a corresponding plurality of sliding shift forks, each arranged to cause a respective engagement sleeve to slide between a neutral position and at least one shift position, a rotary drum having on its outer cylindrical surface a corresponding plurality of guide grooves in each of which a respective stud slidably engages for translation with a respective shift fork in the sliding direction of this latter, and an actuation unit arranged to cause the drum to rotate stepwise among a plurality of angular positions each corresponding to predetermined positions of the engagement sleeves.
Abstract:
A gear change device for a motor vehicle includes a first and a second primary shaft coaxial with respect to each other, selectively connectable to the driving shaft of the motor vehicle by means of a double clutch engagement device, and a first and a second secondary shaft, whose axes are parallel and spaced from the common axis of said primary shafts, and having respective output gear wheels intended to mesh with the gear wheel of a differential. A plurality of pairs of gear wheels correspond to a plurality of forward gear ratios and to at least one reverse gear ratio. The gears of each pair are one rigidly connected in rotation with one of the primary shafts or with one of the secondary shafts while the other is freely rotatable respectively on one of the secondary shafts or on one of the primary shafts. A parking gear wheel is operatively connected to said first secondary shaft cooperating with a lock device for locking the gear change device in the parking condition. The parking gear wheel is rotatably mounted on a fourth axis, parallel and spaced both with respect to the common axis of the two primary shafts and with respect to the axes of the two secondary shafts.
Abstract:
A method of mounting a first drum and a second drum of a double-drum sequential gear control device for a motor-vehicle gearbox in a predefined relative angular position is provided. In a mounted condition, the first drum is rotatably arranged about a first rotation axis and the second drum is rotatably arranged about a second rotation axis parallel to but not coincident with the first rotation axis. The method includes forming a first positioning hole in a first position of the first drum and forming a second positioning hole in a second position of the second drum. The method also includes arranging the first drum and the second drum in the predefined relative angular position and locking the first drum and the second drum in the predefined relative angular position. The locking includes engaging the first and second positioning holes with a locking device. The method further includes disengaging the locking device from the first and second positioning holes of the first and second drums once mounting of the gear control device is completed.
Abstract:
A transmission includes a first primary shaft carrying driving gearwheels associated to the odd gears and to the reverse gear, a second primary shaft coaxial to the first shaft and carrying driving gearwheels associated to the even gears, and at least one secondary shaft carrying a plurality of idle driven gearwheels directly or indirectly meshing with the driving gearwheels. The gearbox is also provided with a gear shift device having sliding engagement sleeves are each arranged to connect each time a driven gearwheel corresponding to a given gear for rotation with the respective secondary shaft. Corresponding sliding shift forks are each arranged to cause a respective engagement sleeve to slide between a neutral position and at least one shift position. A rotary drum has a corresponding guide grooves on its outer cylindrical surface in each of which a respective stud slidably engages, and is rigidly connected for translation with a respective shift fork in the sliding direction of the shift fork. An actuation unit is arranged to cause the drum to rotate stepwise among angular positions, each corresponding to predetermined positions of the engagement sleeves. The guide grooves of the drum are shaped so that in a first angular position the engagement sleeves are positioned to engage at the same time the second gear and the reverse gear.
Abstract:
The device comprises four shift forks, each slidable among a first engagement position, a second engagement position and an intermediate neutral position between the two engagement positions, and an operating unit comprising four double-acting hydraulic actuators identical to each other and arranged to control each the displacement of a respective shift fork among the two engagement positions and the neutral position. The operating unit further comprises a support plate having holes for fixing to the gear case, and an actuator block accommodating the hydraulic actuators. The support plate and the actuator block are integrated to form a single body. In the assembled condition of the operating unit on the gear case, the actuator block is disposed on the side of the support plate facing towards the inside of the gear case.
Abstract:
In an automotive servo-assisted mechanical transmission, an electro-hydraulic actuation group has an actuation unit, a power unit able to provide hydraulic pressure to the actuation unit and an electronic control unit, the actuation and power units being equipped with respective components that are all mounted on a hydraulic casing of the actuation unit so as to define with one another a single assembly structurally separated from the electronic control unit, at least part of the components being equipped with respective electrical connectors that are arranged in a manner such that they can all be engaged by a same multiple electrical connector device.
Abstract:
A gear change device for a motor vehicle includes a first and a second primary shaft coaxial with respect to each other, selectively connectable to the driving shaft of the motor vehicle by means of a double clutch engagement device, and a first and a second secondary shaft, whose axes are parallel and spaced from the common axis of said primary shafts, and having respective output gear wheels intended to mesh with the gear wheel of a differential. A plurality of pairs of gear wheels correspond to a plurality of forward gear ratios and to at least one reverse gear ratio. The gears of each pair are one rigidly connected in rotation with one of the primary shafts or with one of the secondary shafts while the other is freely rotatable respectively on one of the secondary shafts or on one of the primary shafts. A parking gear wheel is operatively connected to said first secondary shaft cooperating with a lock device for locking the gear change device in the parking condition. The parking gear wheel is rotatably mounted on a fourth axis, parallel and spaced both with respect to the common axis of the two primary shafts and with respect to the axes of the two secondary shafts.
Abstract:
A rotary drum for a gear control device for a motor-vehicle gearbox. The drum is rotatable about a rotation axis and includes two guide channels on a cylindrical lateral surface of the drum arranged to guide in slidable manner at least one follower member. The rotary movement of the drum about the rotation axis is converted into translatory movement of said at least one follower member. A series of positioning notches are provided on the cylindrical lateral surface of the drum and spaced apart angularly along a circumference of the drum for snap-engagement by a stop member associated with the drum. The positioning notches are axially interposed between the two guide channels. Two rings of radial through-holes are provided on the cylindrical lateral surface of the drum, each axially interposed between the positioning notches and a respective guide channel
Abstract:
The hybrid propulsion system for an internal combustion engine having a mechanical gearbox and an electric machine. A gear shift device includes a plurality of sliding engagement sleeves, each arranged to connect a driven gearwheel for rotation with the respective secondary shaft, a corresponding plurality of sliding shift forks, each arranged to cause a respective engagement sleeve to slide between a neutral position and at least one shift position, a rotary drum having on its outer cylindrical surface a corresponding plurality of guide grooves in each of which a respective stud slidably engages for translation with a respective shift fork in the sliding direction of this latter, and an actuation unit arranged to cause the drum to rotate stepwise among a plurality of angular positions each corresponding to predetermined positions of the engagement sleeves.
Abstract:
The gear selector fork comprises a body forming a pair of support plates having respective coaxial through-holes for supporting the fork slidably along a stationary rod of the gearbox, a pair of prongs fixed to the body and forming at their distal ends respective actuating portions able to operate a sliding coupling sleeve of the gearbox, and an actuating nose fixed to the body so as to impart to the fork the sliding movement along the stationary rod for engagement of the desired gear. The body and the prongs are formed so as to allow two forks with identical body and prongs to be mounted on the same stationary rod being superimposed at least partially in the direction of sliding along the stationary rod. The prongs are welded to one of the support plates of the body and extend on the same side as the zone where they are welded to the body, relative to the axis of the through-holes.