| 摘要 |
PROBLEM TO BE SOLVED: To provide an automatic transmission which can reduce the number of engagement elements while maintaining the number of gear change stages.SOLUTION: An automatic transmission 100 comprises: planetary gear mechanisms PG1 to PG4; a brake B which fixes a third carrier C3 and a fourth sun gear S4 which are connected to each other to a housing 13 so as to be engaged and disengaged; a first clutch Cl1 which connects an input shaft 11 and a first carrier C1 which are connected to each other to a second ring gear R2 and a third sun gear S3 which are connected to each other so as to be engaged and disengaged; a second clutch Cl2 which connects the third carrier C3 and the fourth sun gear S4 which are connected to each other to a second carrier C2 so as to be engaged and disengaged; a third clutch Cl3 which connects a third ring gear R3 and a fourth ring gear R4 which are connected to each other to the second carrier C2 so as to be engaged and disengaged; and a fourth clutch Cl4 which connects the third ring gear R3 and the fourth ring gear R4 which are connected to each other to the first carrier C1 so as to be engaged and disengaged. |
