A planetary gear train of an automatic transmission for the vehicle may include: an input shaft receiving torque of an engine; an output shaft outputting torque; a first planetary gear set including first, second, and third rotation elements; a second planetary gear set including fourth, fifth, and sixth rotation elements; a third planetary gear set including seventh, eighth, and ninth rotation elements; and a fourth planetary gear set including tenth, eleventh, and twelfth rotation elements.

A gearing device for a motor vehicle, which is equipped with an input shaft that can be operationally connected to a drive unit, as well as a first output shaft and a second output shaft, wherein the first output shaft is connected or can be connected via a first gear with a first partial shaft of a wheel axle and the second output shaft is operationally connected or can be operationally connected via a second gear with a second partial shaft of the wheel axle.

A clutch that includes a friction plate; a separator plate; a clutch hub; and a piston that presses the friction plate and the separator plate, wherein the clutch hub includes a hub on which an inner peripheral portion of the friction plate or the separator plate is fitted, a tubular shaft that movably supports the piston, and an engagement oil chamber defining wall that together with the piston defines an engagement oil chamber to which an engagement oil pressure is supplied, the hub is spline-fitted on a gear of a planetary gear so as to rotate with the gear, and the tubular shaft is rotatably supported by a central shaft and is fitted by a spigot joint in the gear.

A tolerance ring is formed in an inner circumference of a clutch drum at a more forward position than a spline-fitted part in a forward direction during assembly of the clutch drum to a third sun gear; thus, the tolerance ring is located closer to an axial end of the clutch drum than to the spline-fitted part. Accordingly, it becomes easier to carry out grooving to form an annular groove for housing the tolerance ring therein in the inner circumference of the clutch drum, and thereby deterioration of machinability is suppressed.

When a third sun gear is fitted into a fitting hole of a clutch drum, external circumferential spline teeth and internal circumferential spline teeth that configure a spline-fitted part start meshing with each other before a tolerance ring comes into contact with the third sun gear and the clutch drum. Accordingly, the external circumferential spline teeth and the internal circumferential spline teeth mesh with each other, thereby centering the third sun gear and the clutch drum, thus accurately assembling the third sun gear and the clutch drum without causing eccentricity thereof

On simultaneous shifts in which shift control of virtual gear positions overlaps shift control of mechanical gear positions, an electronic control unit is configured to delay output of a shift command on the virtual gear position such that shifts of the virtual gear position and the mechanical gear position are performed in synchronization. Therefore, the virtual gear position and the mechanical gear position are shifted in synchronization, irrespective of a difference between the shift response times, and the feeling of strangeness given to the driver due to shift shock, or the like, is suppressed.

A planetary gear train of an automatic transmission for a vehicle having an input shaft for receiving torque of an engine; an output shaft for outputting torque; a first planetary gear set including first, second, and third rotation elements; a second planetary gear set including fourth, fifth, and sixth rotation elements; a third planetary gear set including seventh, eighth, and ninth rotation elements; and a fourth planetary gear set including tenth, eleventh, and twelfth rotation elements, improves power delivery performance and fuel economy by achieving at least ten forward speed stages.

A planetary gear train of an automatic transmission for a vehicle having an input shaft for receiving torque of an engine; an output shaft for outputting torque; a first planetary gear set including first, second, and third rotation elements; a second planetary gear set including fourth, fifth, and sixth rotation elements; a third planetary gear set including seventh, eighth, and ninth rotation elements; and a fourth planetary gear set including tenth, eleventh, and twelfth rotation elements, improves power delivery performance and fuel economy by achieving at least ten forward speed stages.

An automatic transmission, which is configured such that there is no difference of rotation between a third sun gear and an intermediate shaft in a state where a second clutch is brought into a release state and a seventh speed stage is established, is provided. In the automatic transmission, at the time of a gear shift from a tenth speed stage where second and third clutches and a first brake are brought into an engagement state to a seventh speed stage where first, third, and fourth clutches are brought into an engagement state, the fourth clutch is engaged and the first brake is released to establish the seventh speed stage with the second clutch in the engagement state. Then, the first clutch is engaged and the second clutch is released to make transition to the seventh speed stage with the second clutch in the release state.

A transmission for an opposed-piston engine with two crankshafts includes a crankshaft gear train that combines the torque inputs from the two crankshafts and a gear arrangement coupled to the gear train that is operable to obtain various speed ratios for an output torque drive.