Abstract: A planetary gear train may include input and output shafts, first to third planetary gear sets respectively having first to third, fourth to sixth, and seventh to ninth elements, a first shaft connected to the first element, and selectively connectable to the input shaft, a second shaft connected to the fifth element, and selectively connectable to the input shaft, a third shaft connected to the eighth element and the output shaft, a fourth shaft connected to the second element and the fourth element, a fifth shaft connected to the third and seventh elements, a sixth shaft connected to the sixth element and the transmission housing, and a seventh shaft connected to the ninth element and selectively connectable to the transmission housing.

Abstract: A power transmission system of a vehicle may include: a first input shaft selectively connectable to an engine output through a first clutch; a second input shaft selectively connectable to the engine output through a second clutch; a first intermediate shaft; a second intermediate shaft; an output shaft disposed in parallel with and apart from the first intermediate shaft and transmitting power from the first intermediate shaft and the second intermediate shaft to a final reduction gear of a differential apparatus; a motor/generator fixedly connected to any one of the first input shaft and the first intermediate shaft; a continuously variable shifting device operably connecting the first input shaft to the first intermediate shaft; and a plurality of shifting gear sets operably connecting the second input shaft, the first and the second intermediate shaft and the output shaft with each other.

Abstract: A power transmission apparatus may include engine; first motor/generator; first rotation element fixed to the engine, second rotation element fixed to the first motor/generator, and third rotation element; first input shaft selectively connectable to the third rotation element; second input shaft selectively connectable to the third rotation element; third input shaft; an output shaft; an idle shaft operably connected to the second input shaft and the third input shaft; and speed stage module including drive gears rotatably disposed on the first input shaft, the third input shaft, or the idle shaft, driven gears meshed with the drive gears and fixed on the output shaft, and power delivery gears and an idle gear fixed on the second input shaft, the third input shaft, or the idle shaft, and synchronizers selectively connecting at least one among the drive gears to the first input shaft, the third input shaft, or the idle shaft.

Abstract: A planetary gear train may include first to third gear sets having three elements, respectively, the first and second gear sets mounted on input shaft, the third gear set mounted on output shaft, first shaft fixed to the first element and selectively connectable to the input shaft and housing, second shaft fixed to the second and sixth elements and selectively connectable to the input shaft and the housing, third shaft fixed to the third and fifth elements, fourth shaft fixed to the fourth element and selectively connectable to the housing, fifth shaft fixed to the seventh element and engaged with the third shaft, sixth shaft fixed to the eighth element and selectively connectable to the input shaft, seventh shaft fixed to the ninth element and the output shaft and selectively connectable to the fifth shaft, and two transfer gears each engaged between corresponding pair of shafts.

Abstract: Ten forward speeds and one reverse speed are achieved by a power transmission apparatus for a vehicle including a double clutch, a plurality of input, output, and idle shafts, a plurality of gears fixed to or rotatable on the shafts, a plurality of synchronizers selectively synchronizing gears to the shafts.

Abstract: A planetary gear train may include input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to thirteenth elements, a first shaft connected to the second element and the input shaft, a second shaft connected to the eleventh element and the output shaft, a third shaft connected to the first and seventh elements, a fourth shaft connected to the fifth and twelfth elements, a fifth shaft connected to the eighth and tenth elements, a sixth shaft connected to the thirteenth element, and a plurality of shafts each selectively connecting a corresponding element to a transmission housing, the corresponding element being an element of the first, second and third planetary gear sets which is not interconnected.

Abstract: Nine forward speeds and one reverse speed are achieved by a power transmission apparatus for a vehicle including a double clutch, a plurality of input, output, and idle shafts, a plurality of gears fixed to or rotatable on the shafts, a plurality of synchronizers selectively synchronizing gears to the shafts.

Abstract: A planetary gear train includes input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements. The planetary gear train includes a first shaft connected with the first element and the sixth rotational element, and selectively connected with the input shaft, a second shaft connected with the ninth element and selectively connected with the input shaft, a third shaft connected with the eleventh element and the output shaft, a fourth shaft connected with the second, fifth, and twelfth rotational elements, a fifth shaft connected with the fourth and seventh rotational elements. The planetary gear train includes a plurality of additional shafts each selectively connecting a corresponding element to a transmission housing, the corresponding element being an element of the first, third, and fourth planetary gear sets that is not interconnected.

Abstract: A planetary gear train of an automatic transmission for a vehicle is disclosed. The planetary gear train includes an input shaft for receiving an engine torque, an output shaft for outputting a torque, four planetary gear sets each having three rotational elements. The planetary gear train further comprises a plurality of additional shafts, each of which is selectively connected to the transmission housing and fixedly connected to a rotation element of the first, second, third, and fourth planetary gear set that is not fixedly connected with any of the first to fifth shafts.

Abstract: A planetary gear train includes an input shaft and an output shaft. A first planetary gear set has first, second, and third rotational elements. A second planetary gear set has fourth, fifth, and sixth rotational elements. A third planetary gear set has seventh, eighth, and ninth rotational elements. A fourth planetary gear set has tenth, eleventh, and twelfth rotational elements. A first shaft is fixedly connected with the twelfth rotational element and fixedly connected with the input shaft. A second shaft is fixedly connected with the fifth rotational element and the eighth rotational element, and fixedly connected with the output shaft. A third shaft is fixedly connected with the fourth rotational element. A fourth shaft is fixedly connected with the seventh rotational element. A fifth shaft is fixedly connected with the sixth rotational element and the ninth rotational element.

Abstract: A planetary gear train of an automatic transmission for a vehicle is disclosed. A planetary gear train of claim of an automatic transmission for a vehicle, includes an input shaft for receiving an external torque; an output shaft for outputting a shifted torque; a first planetary gear set having first, second, and third rotational elements; a second planetary gear set having fourth, fifth, and sixth rotational elements; a third planetary gear set having seventh, eighth, and ninth rotational elements; a fourth planetary gear set having tenth, eleventh, and twelfth rotational elements; a first shaft fixedly connected with the second rotational element, the sixth rotational element, the seventh rotational element, and the input shaft; a second shaft fixedly connected with the eleventh rotational element, and the output shaft; and a third shaft fixedly connected with the first rotational element and the tenth rotational element.

Abstract: A planetary gear train may include input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements, a first shaft connected to the second element and the input shaft, a second shaft connected to the twelfth element and the output shaft, a third shaft connected to the first and seventh elements, a fourth shaft connected to the fifth and eleventh elements, a fifth shaft connected to the eighth and tenth elements, and a plurality of shafts each selectively connecting a corresponding element to a transmission housing, the corresponding element being an element of the first, second and third planetary gear sets which is not interconnected.

Abstract: A clutching device of an automatic transmission may include a clutch drum connected to a first rotation element, a clutch connected to the clutch drum and a second rotation element, and a piston device to operate the clutch, wherein the piston device may include a first piston forming a first sealed space with the first rotation element and the clutch drum and moving toward the clutch by a hydraulic pressure supplied to the first sealed space, a second piston forming a second sealed space with the first piston and moving toward the clutch to directly press the clutch by a hydraulic pressure supplied to the second sealed space, a spring retainer disposed on the first rotation element and forming a third space with the second piston and the first rotation element, and a return spring stored in the third space and abutted by the spring retainer and the second piston.

Abstract: A power delivery device configured for an automatic transmission may include a brake disposed between a rotation element connected to a brake hub and a transmission housing, and a piston device disposed corresponding to the brake and operating the brake by hydraulic pressure, wherein the power delivery device configured for an automatic transmission selectively connects the rotation element to the transmission housing by use of dual pistons.

Abstract: A power delivery device for an automatic transmission may include a clutch drum connected to an input shaft, a clutch disposed in the clutch drum and including a friction member connected to a planet carrier of a planetary gear set through a clutch hub, and a piston device disposed corresponding to the clutch and operating the clutch by hydraulic pressure.

Abstract: A planetary gear train of an automatic transmission may include input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements, a first shaft fixed with the input shaft, the third element, and the fifth element, a second shaft fixed with the ninth and eleventh elements, and selectively connectable to the input shaft, a third shaft fixed with the eighth and twelfth elements, and the output shaft, a fourth shaft fixed with the first element, a fifth shaft fixed with the second and sixth elements, a sixth shaft fixed with the tenth element, and a plurality of shafts, each of which is selectively connectable to a housing and fixed to an element of the first and second gear sets which is not fixed with any of the first to sixth shafts.

Abstract: A planetary gear train apparatus of an automatic transmission may include input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements, a first shaft fixed with the third element, and selectively connectable to the input shaft, a second shaft fixed with the fourth element, and selectively connectable to the input shaft, a third shaft fixed with the eleventh element and the output shaft, a fourth shaft fixed with the first, sixth, and ninth elements, a fifth shaft fixed with the seventh and twelfth elements, and shafts, each of which is selectively connectable to a housing and fixed to an element of the first to fourth gear sets which is not fixed with of the first to fifth shafts.

Abstract: A planetary gear train includes input and output shafts; first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements, respectively; a first shaft connected with the second and twelfth elements, and selectively connected with the input shaft, a second shaft connected with the sixth element, and selectively connected with the input shaft, a third shaft connected with the eighth element and the output shaft, a fourth shaft connected with the first, fourth, and tenth elements, a fifth shaft connected with the third, fifth, and ninth element, at least one additional shaft selectively connecting a corresponding element to a transmission housing, wherein the corresponding element is an element of the first or second planetary gear sets that is not interconnected.

Abstract: A planetary gear train includes input and output shafts, first to fourth planetary gear sets respectively having first to third, fourth to sixth, seventh to ninth, and tenth to twelfth elements. The planetary gear train includes a first shaft connected with the first and fourth elements and selectively connected with the input shaft, a second shaft connected with the sixth element and selectively connected with the input shaft, a third shaft fixedly connected with the eighth and twelfth elements and the output shaft, a fourth shaft connected with the second, fifth, and seventh elements, and a fifth shaft connected with the third and eleventh elements, The planetary gear train includes a plurality of shafts each selectively connecting a corresponding element to a transmission housing, the corresponding element being an element of the third and fourth planetary gear sets that is not interconnected.

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 an output torque, a first planetary gear set including first, second, and third rotational elements, a second planetary gear set including fourth, fifth, and sixth rotational elements, a third planetary gear set including seventh, eighth, and ninth rotational elements, and a fourth planetary gear set including tenth, eleventh, and twelfth rotational elements.