Multi-stage transmission for vehicle

摘要

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.

主权项

1. A multi-stage transmission for a vehicle, comprising:
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 forces, 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 planetary gear devices; wherein a first rotary element of the first planetary gear device is installed to be fixable by one shifting element of the at least six shifting elements and permanently connected to a second rotary element of the third planetary gear device and a third rotary element of the fourth planetary gear device, a second rotary element of the first planetary gear device is variably connected to a third rotary element of the second planetary gear device and a third rotary element of the third planetary gear device, and a third rotary element of the first planetary gear device is variably connected to a first rotary element and a second rotary element of the second planetary gear device; wherein the first rotary element of the second planetary gear device is installed to be fixable by another shifting element of the at least six shifting elements, the second rotary element of the second planetary gear device is permanently connected to the input shaft, and the third rotary element of the second planetary gear device is permanently connected to a first rotary element of the third planetary gear device; wherein the first rotary element of the third planetary gear device is permanently connected to a first rotary element of the fourth planetary gear device; and wherein a second rotary element of the fourth planetary gear device is permanently connected to the output shaft.