A transmission system (10), especially for a motor vehicle, having around an axis (O) at least an input shell (12) that is rotationally connected to a driving shaft and to a drive web (18) in order to rotationally connect said input shell (12) to a double wet clutch mechanism (20) that, having at least a first clutch (E1) and a second clutch (E2) respectively of the multiple-disc type, is controlled to selectively couple said driving shaft to a first driven shaft (A1) and to a second driven shaft (A2), wherein the input shell (12) and the drive web (18) are rotationally connected by connecting means (24), which are constituted in particular by rivets (25), with zero angular clearance.

A reaction plate for a clutch including an annular body, the annular body including an inner circumferential edge, an outer circumferential edge, a first surface between the inner and outer circumferential edges and facing a first axial direction and a second surface between the inner and outer circumferential surfaces and facing a second axial direction, the second surface including recesses covering at least 50 percent of the second surface. A clutch assembly including a friction plate, the friction plate having a first axially-facing surface including a friction material, a reaction plate, the reaction plate having a second axially-facing surface including recesses covering at least 50 percent of the second axially-facing surface and an actuation means arranged to displace the friction plate or the reaction plate such that the first and second axially-facing surfaces frictionally engage. A method of fabricating a reaction plate for a clutch.

A dual clutch that includes a first clutch, a second clutch, a ball ramp assembly and at least one actuator is provided. The first clutch engages and disengages a first set of gears. The second clutch engages and disengages a second set of gears. The at least one ball ramp assembly includes at least one ball, first member and a second member. The first member includes a ball pocket for each ball. The second member has at least one ball ramp. The at least one ball partially received in an associated ball pocket of the first member and ball ramp of the second member. The at least one actuator is configured and arranged to rotate one of the first member and the second member to cause the at least one ball ramp assembly to activate at least one of the first clutch and the second clutch.

A dual clutch unit includes an outer disk carrier rotationally driven about a rotation axis, first and second inner disk carriers, first and second disk packs for torque transmission between the outer disk carrier and the respective inner disk carrier, wherein the first and second inner disk carriers are arranged rotatably relative to each other about the rotation axis, a central oil supply to supply the first and second disk packs with coolant, a first distributor channel being formed in the first inner disk carrier and comprising a feed opening through which the first distributor channel is fluidly connected to the central oil supply, a second distributor channel being formed in the second inner disk carrier and being fluidly connected to the central oil supply via the first distributor channel, and drain channels being formed in the inner disk carriers to conduct the coolant into the disk packs.

A fail-safe friction clutch assembly for a vehicle accessory, particularly to drive a vehicle cooling pump, and more particularly as part of a dual mode drive for a cooling pump, together with an electric motor. The friction clutch assembly includes a friction plate member connected to a central rotatable shaft member used for operating the vehicle accessory. A pair of friction lining members are positioned on opposite sides of the friction plate member. An armature member is spring biased to axially force the friction plate member and friction lining member against a housing or cover which is rotating at input speed. A solenoid assembly is used to overcome the spring bias and pull the armature and friction plate member away from the housing.

A fail-safe friction clutch assembly for a vehicle accessory, particularly to drive a vehicle cooling pump, and more particularly as part of a dual mode drive for a cooling pump, together with an electric motor. The friction clutch assembly includes a friction plate member connected to a central rotatable shaft member used for operating the vehicle accessory. A pair of friction lining members are positioned on opposite sides of the friction plate member. An armature member is spring biased to axially force the friction plate member and friction lining member against a housing or cover which is rotating at input speed. A solenoid assembly is used to overcome the spring bias and pull the armature and friction plate member away from the housing.

A hybrid-vehicle system includes an internal combustion engine configured to deliver a first rotational torque to a crankshaft. The first rotational torque is a maximum torque deliverable by the internal combustion engine. The hybrid-vehicle system also includes a transmission selectively rotatably coupled to the crankshaft, and an assembly including an electric machine rotatably coupled to the transmission and configured to deliver a second rotational torque directly to the transmission. The assembly also includes a one-way clutch configured to rotationally couple the crankshaft and the transmission. The assembly further includes a friction clutch moveable between an engaged state where the crankshaft and the transmission are rotationally coupled, and a disengaged state where the crankshaft and the transmission are rotationally decoupled. The friction clutch is further defined as a latching friction clutch.

The invention relates to a method for carrying out a starting operation of a motor vehicle having a gear train that includes a dual clutch transmission with a first clutch that carries the odd-numbered gears, and a second clutch that carries the even-numbered gears, wherein the second clutch of the dual clutch transmission is used, at least in part, for preloading the gear train.

Provided is an automatic transmission with a compact arrangement that prevents rotation of a hub member, and efficiently supplies lubrication hydraulic oil to the friction plates. The automatic transmission comprises a brake in which a plurality of friction plates are arranged between the hub member and a drum member, wherein a biasing member, an engagement hydraulic pressure chamber, and a disengagement hydraulic pressure chamber are arranged radially inward of the friction plates at positions radially overlapping each other. The hub member comprises: a first hub member comprising a cylindrical portion having a splined region with which the friction plates are spline-engaged, wherein the first hub member s spline-engaged with a transmission casing; and a second hub member formed with a part of a lubrication oil supply passage, wherein the second hub member is fittingly engaged with the transmission casing such that it is connected to a valve body.

Provided is an automatic transmission with a compact arrangement that prevents rotation of a hub member, and efficiently supplies lubrication hydraulic oil to the friction plates. The automatic transmission comprises a brake in which a plurality of friction plates are arranged between the hub member and a drum member, wherein a biasing member, an engagement hydraulic pressure chamber, and a disengagement hydraulic pressure chamber are arranged radially inward of the friction plates at positions radially overlapping each other. The hub member comprises: a first hub member comprising a cylindrical portion having a splined region with which the friction plates are spline-engaged, wherein the first hub member s spline-engaged with a transmission casing; and a second hub member formed with a part of a lubrication oil supply passage, wherein the second hub member is fittingly engaged with the transmission casing such that it is connected to a valve body.