Method and apparatus for controlling automatic transmission
US5285880A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1992 |
| Grant date | Feb 15, 1994 |
| Priority date | — |
| Expiry date | May 22, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2306/24
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In an automatic transmission including first and second planetary gear sets and a plurality of friction elements, during an up-shift and a time after the up-shift, a hydraulic pressure of a released friction element is kept at a predetermined value corresponding to the biasing force of a return spring set in the control valve of the friction element for a predetermined time after the end of the up-shift. When a down-shift is carried out immediately after the above-mentioned up-shift, the engagement of the released friction element is rapidly carried out since the hydraulic pressure of the friction element is kept at the predetermined value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.