Abstract: A transmission for vehicles may include a first planetary gear set, a second planetary gear set, a third planetary gear set, and a fourth planetary gear set each including three rotary elements, and a plurality of friction members, in which the friction members are connected to at least one or more of the rotary elements of the planetary gear sets and control rotation of the rotary elements.

Abstract: A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving torque of an engine, an output shaft configured to output changed torque of the engine, 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.

Abstract: A multi-stage transmission for a vehicle may include an input shaft; an output shaft; first to fourth planetary gear devices transmitting rotary force between the input and output shafts, each of them having three rotary elements; and at least six shifting elements connected to the rotary elements of the planetary gear devices; wherein first rotary element of the first planetary gear device is installed to be fixable by any one of the shifting elements and variably connected to second rotary element of the second planetary gear device, second rotary element is continuously connected to the input shaft and variably connected to third rotary element of the second planetary gear device, and third rotary element is variably connected to the second rotary element of the second planetary gear device and continuously connected to first rotary element of the third planetary gear device.

Abstract: A transmission for a vehicle may include a first planetary gear set, a second planetary gear set, a third, planetary gear set, and a fourth planetary gear set each including three rotary elements, and a plurality of friction members, in which the friction members are connected to at least one or more of the rotary elements of the planetary gear sets and control rotation of the rotary elements.

Abstract: A planetary gear train of an automatic transmission for vehicles may include an input shaft receiving torque of an engine, an output shaft outputting changed torque of the engine, a first planetary gear set, a second planetary gear set, a third planetary gear set, a fourth planetary gear set, a first rotation shaft, a second rotation shaft, a third rotation shaft, a fourth rotation shaft selectively connected to the input shaft, a fifth rotation shaft selectively connected to the input shaft or selectively connected to the transmission housing, a sixth rotation shaft directly connected to the output shaft to be continuously operated as an output element, a seventh rotation shaft selectively connected to the transmission housing, an eighth rotation shaft selectively connected to the third rotation shaft, a ninth rotation shaft directly connected to the input shaft to be continuously operated as an input element, and six friction elements.

Abstract: A multi-stage transmission for a vehicle includes an input shaft, an output shaft, first to fourth planetary gear devices each having three rotary elements and transmitting rotary forces between the input and output shafts, and at least six shifting elements connected to the rotary elements of the planetary gear devices. Of the first planetary gear device, the first rotary element is installed to be fixable by any one of the shifting elements and permanently connected to the second rotary element of the third planetary gear device and the third rotary element of the fourth planetary gear device, the second rotary element is variably connected to the third rotary element of the second planetary gear device and the third rotary element of the third planetary gear device, and the third rotary element is variably connected to the first and second rotary elements of the second planetary gear device.

Abstract: A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving power from an engine, an output shaft outputting power changed in speed, a first planetary gear set, a second planetary gear set, a third planetary gear set, a fourth planetary gear, a first rotating shaft selectively connected with a transmission housing, a second rotating shaft, a third rotating shaft selectively connected with the transmission housing, a fourth rotating shaft directly connected with the input shaft so as to be continuously operated as an input element, a fifth rotating shaft, a sixth rotating shaft selectively connected with the first, second, and fifth rotating shafts, a seventh rotating shaft, an eighth rotating shaft selectively connected with the seventh rotating shaft and simultaneously directly connected with the output shaft, and six friction elements.

Abstract: A planetary gear train of an automatic transmission may include input shaft, output shaft, first planetary gear set including first to third rotation elements, second planetary gear set including fourth to sixth rotation elements, third planetary gear set including seventh to ninth rotation elements, fourth planetary gear set including tenth to twelfth rotation elements, and six control elements disposed at portions selectively connecting between the rotation elements and between the rotation elements and a transmission housing, wherein the input shaft is directly connected to the fourth rotation element and the eighth rotation element, the output shaft is directly connected to the eleventh rotation element, the tenth rotation element is directly connected to the third rotation element while being selectively connected to the seventh rotation element, the second rotation element is selectively connected to the sixth rotation element, and the first rotation element is directly connected to the transmission hou

Abstract: A planetary gear train of an automatic transmission for a vehicle may include an input shaft receiving torque of an engine, an output shaft outputting changed torque of the engine, a first planetary gear set, a second planetary gear set, a third planetary gear set, a fourth planetary gear set, a first rotation shaft, a second rotation shaft, a third rotation shaft directly connected to the output shaft, a fourth rotation shaft selectively connected to the second rotation shaft and selectively connected to a transmission housing, a fifth rotation shaft, a sixth rotation shaft directly connected to the input shaft, and selectively connected to the second rotation shaft, a seventh rotation shaft including the third planet carrier, selectively connected to the first rotation shaft, and selectively connected to the transmission housing, and an eighth rotation shaft including the fourth ring gear and selectively connected to the second rotation shaft.

Abstract: A multi-stage transmission for a vehicle is provided that has at least nine forward shifting stages and one reverse shifting stage with a relatively small number of parts and a configuration such that an engine may be operated at desired operation points, thereby increasing fuel efficiency of the vehicle, and the engine may be operated more quietly, thereby improving the quietness of the vehicle.

Abstract: A multi-stage transmission for a vehicle may include an input shaft, an output shaft, first, second, third and fourth planetary gear devices disposed between the input shaft and the output shaft to transmit rotary force, each of the first, second, third and fourth planetary gear devices having three rotary elements, and at least six shifting elements connected to the rotary elements of the first, second, third and fourth planetary gear devices.

Abstract: A multi-stage transmission for a vehicle may include an input shaft, an output shaft, first, second, third, and fourth planetary gear devices disposed between the input shaft and the output shaft to transmit rotary force, each of the first, second, third, and fourth planetary gear devices having three rotary elements, and at least six shifting elements connected to the three rotary elements of the first, second, third, and fourth planetary gear devices.

Abstract: A multi-stage transmission for a vehicle may include an input shaft, an output shaft, first, second, third, and fourth planetary gear devices disposed between the input shaft and the output shaft to transmit rotary force, each of the first, second, third, and fourth planetary gear devices having three rotary elements, and at least six shifting elements connected to the three rotary elements of the first, second, third, and fourth planetary gear devices,

Abstract: A gear train may include an input shaft adapted to receive torque of an engine, an output shaft adapted to output changed torque, a first planetary gear set including a first sun gear, a first planet carrier, and a first ring gear as rotation elements thereof, a second planetary gear set including a second sun gear, a second planet carrier, and a second ring gear as rotation elements thereof, and a third planetary gear set including a third sun gear, a third planet carrier, and a third ring gear as rotation elements thereof.

Abstract: A multi-stage transmission may include an input shaft and an output shaft; a first planetary gear device, a second planetary gear device, a third planetary gear device, and a fourth planetary gear device provided between the input shaft and the output shaft to transfer a torque and each planetary gear set including three rotating elements; and at least six shifting elements connected to the rotating elements of the first, second, third, and fourth planetary gear devices.

Abstract: A multistage automatic transmission may include an input shaft, a first composite planetary gear set including first and second planetary gear sets, each of the first and second planetary gear sets including three rotary members, a first brake, a first clutch, a second brake, a second clutch selectively connecting a pair of rotary members of the first composite planetary gear set that are selectively connected to each other, and a second composite planetary gear set arranged coaxially with the input shaft and including a plurality of rotary members, wherein the plurality of rotary members include a rotary member connected to the first composite planetary gear set, a rotary member connected to the input shaft, and a further rotary member connected to an output shaft, at least two rotary members of the plurality of rotary members in the second composite planetary gear set being connected to two friction members.

Abstract: A planetary gear train of an automatic transmission may include a first shaft receiving engine torque, a second shaft disposed in parallel to the first shaft, a first planetary gear set on the first shaft including a first element operated as a fixed element, a second element directly connected to the first shaft, and a third element, a compound planetary gear set formed by combining a second planetary gear set and a third planetary gear set including a fourth element selectively connected to the first shaft and the third element, a fifth element connected to an output gear, a sixth element selectively connected to the first element, and a seventh element selectively connected to the third element through a gear.

Abstract: A planetary gear train may include a first shaft receiving torque of an engine, a second shaft selectively connected to the first shaft through an externally-meshed gear, a first planetary gear set disposed on the first shaft, and including a first rotation element selectively operated as a fixed element, a second rotation element directly connected to the first shaft, and a third rotation element, a compound planetary gear set including a fourth rotation element selectively connected to the third rotation element through an externally-meshed gear, a fifth rotation element selectively connected to the first rotation element through an externally-meshed gear, a sixth rotation element directly connected to an output gear, and a seventh rotation element directly connected to the second shaft and selectively connected to the third rotation element through an externally-meshed gear, and frictional elements selectively connecting the rotation elements with each other or with a transmission housing.

Abstract: A planetary gear train of an automatic transmission may include: a first shaft; a second shaft parallel with the first shaft; a first gear set on the first shaft including a first element selectively connected to the first shaft, a second element selectively connected to the first shaft and a transmission housing, and a third element; a second gear set on the second shaft including a fourth element operably connected to the first element and selectively connected to the first shaft, a fifth element connected to the third element and directly connected to an output gear, and a sixth element selectively connected to the first shaft and selectively connected to the housing; three transfer gears; and frictional elements including clutches selectively connecting the first shaft to elements of the first and second gear sets and brakes selectively connecting elements of the first and second gear sets to the housing.

Abstract: A gear train may include an input shaft adapted to receive torque of an engine, an output shaft adapted to output changed torque, a first planetary gear set including a first sun gear, a first planet carrier, and a first ring gear as rotation elements thereof, a second planetary gear set including a second sun gear, a second planet carrier, and a second ring gear as rotation elements thereof, and a third planetary gear set including a third sun gear, a third planet carrier, and a third ring gear as rotation elements thereof.