| 摘要 |
PROBLEM TO BE SOLVED: To reduce friction loss by transmitting a thrust load generated by a gear of an automatic transmission to a transmission case so that the load goes through bearings as little as possible.SOLUTION: An automatic transmission includes thrust bearings T7 and T8 between a third sun gear Sc of a third planetary gear mechanism PGSc and a second sun gear Sb of a second planetary gear mechanism PGSb. Accordingly, a thrust load acting on the second sun gear Sb of the second planetary gear mechanism PGSb is transmitted from the thrust bearings T7 and T8 to an input shaft 12 via the third sun gear Sc of the third planetary gear mechanism PGSc, and the transmission of the thrust load from the third planetary gear mechanism PGSc to the input shaft 12 via a fourth planetary gear mechanism PGSd is thereby avoided as much as possible. As a result, friction loss can be reduced in a plurality of thrust bearings T9 to T12 lying between components of the third planetary gear mechanism PGSc and the fourth planetary gear mechanism PGSd, or the like. |
