Automatic transmission
US6723018B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 2002 |
| Grant date | Apr 20, 2004 |
| Priority date | — |
| Expiry date | Jan 8, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2200/2097
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A speed-reducing gear unit is provided for causing a reduced-speed rotation output member to have a reduced rotation that is slower than rotation of an input shaft. The reduced-speed rotation output member is switched between a reduced-speed rotation state and a free rotation state by rotation state switching means. The reduced-speed rotation of the reduced-speed rotation output member is selectively transferred to fourth and first elements of a speed-changing dual planetary gear unit via first and third control clutches. The rotation of the input shaft is transferred to a second element via a second control clutch. Rotations of the first and second elements are selectively restricted by first and second control brakes. A third element is connected to an output shaft. This makes it possible to provide a high-efficiency automatic transmission that achieves seven or more forward gear ratios so as to allow optimal extraction of engine performance in a high vehicle speed region and reduce the vehicle speed change at the time of a gear shift and therefore provide a good feeling, by adding gear speeds including a locked-up speed at a high gear speed side so that adjacent gear ratios are …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.