Automatic transmission
AssigneeMazda Motor Corporation
InventorsYasuhiro Ogauchi, Shinya Kamada, Tatsuhiko Iwasaki
Life of this patent
Estimating the term…
Abstract
To simplify the hydraulic pressure supply passage to each clutch, an multistage automatic transmission comprises an input part and output part, three clutches, two brakes, and four planetary gear sets, where the first and fourth sets are of a single pinion type and the second and third of a double pinion type. The input and output parts and the planetary gear sets connect to each other and the clutches and brakes decouple components in such a way that enlargement as a whole of the transmission and the deterioration of the responsiveness of the shift control are controlled.
Claims6
An automatic transmission, in a transmission case, comprising in a coaxial arrangement:
- an input part,
- an output part,
- a first planetary gear set including a first sun gear, a first carrier, and a first ring gear,
- a second planetary gear set including a second sun gear, a second carrier, and a second ring gear,
- a third planetary gear set including a third sun gear, a third carrier, and a third ring gear,
- a fourth planetary gear set including a fourth sun gear, a fourth carrier, and a fourth ring gear,
- a first, a second, and a third clutches, and
- a first and a second brakes:
- wherein the first sun gear and the second sun gear are constantly connected, the first ring gear and the fourth carrier are constantly connected, the first brake decouples between the first sun gear, and the second sun gear, and the transmission case, the second brake decouples between the fourth ring gear and the transmission case, and the first planetary gear set and the fourth planetary gear set are configured as a single pinion type:
- wherein, when the second planetary gear set is configured as a double pinion type and the third planetary gear set is configured as a single pinion type, the first carrier and the third carrier are constantly connected, the second carrier and the third sun gear are constantly connected, the input part is constantly connected to the second ring gear, the output part is constantly connected to the first carrier and the third carrier, the first clutch decouples between the third ring gear and the fourth sun gear, the second clutch decouples between the second carrier, the third sun gear, and the fourth sun gear, the third clutch decouples between the input part, the second ring gear, and the fourth sun gear, and
- wherein, when the second planetary gear set is configured as a single pinion type and the third planetary gear set is configured as a double pinion type, the first carrier and the third ring gear are constantly connected, the second ring gear and the third sun gear are constantly connected, the input part is constantly connected to the second carrier, the output part is constantly connected to the first carrier and the third ring gear, the first clutch decouples between the third carrier and the fourth sun gear, the second clutch decouples between the second ring gear, the third sun gear, and the fourth sun gear, and the third clutch decouples between the input part, the second carrier, and the fourth sun gear.
An automatic transmission, in a transmission case, comprising, in a coaxial arrangement:
- an input part,
- an output part,
- a single pinion type first planetary gear set including a first sun gear, a first carrier, and a first ring gear,
- a double pinion type second planetary gear set including a second sun gear, a second carrier, and a second ring gear,
- a single pinion type third planetary gear set including a third sun gear, a third carrier, and a third ring gear,
- a single pinion type fourth planetary gear set including a fourth sun gear, a fourth carrier, and a fourth ring gear,
- a first, a second, and a third clutches, and
- a first and a second brakes:
- wherein the first sun gear and the second sun gear are constantly connected, the first carrier and the third carrier are constantly connected, the first ring gear and the fourth carrier are constantly connected, the second carrier and the third sun gear are constantly connected, the input part is constantly connected to the second ring gear, the output part is constantly connected to the first carrier and the third carrier, the first clutch decouples between the third ring gear and the fourth sun gear, the second clutch decouples between the second carrier, the third sun gear, and the fourth sun gear, the third clutch decouples between the input part, the second ring gear, and the fourth sun gear, the first brake decouples between the first sun gear, the second sun gear, and the transmission case, and the second brake decouples between the fourth ring gear and the transmission case.
An automatic transmission, in a transmission case, comprising, in a coaxial arrangement:
- an input part,
- an output part,
- a single pinion type first planetary gear set including a first sun gear, a first carrier, and a first ring gear,
- a single pinion type second planetary gear set including a second sun gear, a second carrier, and a second ring gear,
- a double pinion type third planetary gear set including a third sun gear, a third carrier, and a third ring gear,
- a single pinion type fourth planetary gear set including a fourth sun gear, a fourth carrier, and a fourth ring gear,
- a first, a second, and a third clutches, and
- a first and a second brakes:
- wherein the first sun gear and the second sun gear are constantly connected, the first carrier and the third ring gear are constantly connected, the first ring gear and the fourth carrier are constantly connected, the second ring gear and the third sun gear are constantly connected, the input part is constantly connected to the second carrier, the output part is constantly connected to the first carrier and the third ring gear, the first clutch decouples between the third carrier and the fourth sun gear, the second clutch decouples between the second ring gear, the third sun gear, and the fourth sun gear, the third clutch decouples between the input part, the second carrier, and the fourth sun gear, the first brake decouples between the first sun gear, the second sun gear, and the transmission case, and the second brake decouples between the fourth ring gear and the transmission case.
Dependencies are inferred from the claim text.