| 摘要 |
<p>Disclosed is an eight-shift automatic transmission for a vehicle. The automatic transmission of the present invention includes an input shaft, an output gear set, an output shaft, a case, and a frictional member. The input shaft is connected to a start clutch or a torque converter. The first gear set is connected to the input shaft and includes a first ring gear, a first linear gear, and a first planetary gear carrier. The output gear set is connected to the first gear set to form a gear ratio with the first gear set and includes a second gear set, a third gear set, and a fourth gear set. The second gear set includes a second ring gear, a second linear gear, and a second planetary gear carrier. The third gear set includes a third ring gear, a third linear gear, and a third planetary gear carrier. The fourth gear set includes a fourth ring gear, a fourth linear gear, and a fourth planetary gear carrier. The output shaft outputs the torque of the output gear set. The case covers the first gear set and output gear set. The frictional member includes a clutch and a brake. The clutch selectively connects the first gear set and output gear set. The brake selectively fixates a part of the output gear set. According to the present invention, the eight-shift automatic transmission for a vehicle having a firm and compact structure while forming eight gears by selectively connecting rotary shafts of the first gear set and output gear set and capable of improving fuel efficiency can be provided.</p> |
