Patent ID: 7931558

Claim:
An automatic transmission comprising: an input shaft; a speed-reducing dual planetary gear comprising: a speed-reducing common carrier bearing rotatably a stepped pinion, having a diametrically-larger pinion portion and a diametrically-smaller pinion portion, and a first pinion meshing with said diametrically-smaller pinion portion and connected directly to said input shaft; a first sun gear meshing with said diametrically-larger pinion portion; a second sun gear meshing with said diametrically-smaller pinion portion; and a speed-reducing common ring gear meshing with said first pinion; a speed-changing dual planetary gear comprising: a speed-changing common carrier bearing rotatably a long pinion and a second pinion meshing with said long pinion and configured to connect to said input shaft; a third sun gear meshing with said long pinion; a fourth sun gear meshing with said second pinion; and a speed-changing common ring gear meshing with said long pinion; an output shaft connected directly to said speed-changing common ring gear; a first clutch configured to selectively connect said speed-reducing common ring gear and said fourth sun gear; a second clutch configured to selectively connect said input shaft and said speed-changing common carrier; a third clutch configured to selectively connect said speed-reducing common ring gear and said third sun gear; a fourth clutch configured to selectively connect said speed-reducing common carrier and said third sun gear; a fifth clutch configured to selectively connect said first sun gear and said third sun gear; a first brake configured to selectively fix said third sun gear; and a second brake configured to selectively fix said speed-changing common carrier.