Shift control method for an automatic transmission
US5882276A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1997 |
| Grant date | Mar 16, 1999 |
| Priority date | — |
| Expiry date | Feb 11, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/0444
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A shift control method for an automotive automatic transmission is provided, which reduces a shift shock particularly at the time of a skip down-shift, and shortens a required shifting time period. An electronic control unit of a shift control apparatus releases the engagement of a clutch of a subsidiary transmission mechanism and engages a one-way clutch so as to establish a gear position not used in the normal speed change when a shift command from the fifth shift position to the third shift position is issued, gradually decreasing a valve opening duty ratio of an electromagnetic valve associated with a brake of a main transmission mechanism from an initial value D.sub.HLi before this gear position is established, determines an average turbine rotation speed changing rate dD.sub.TAVE /dt from the detected turbine rotation speed (S203), and learning correction of the initial value D.sub.HLi is made if the changing rate deviates from a target range (S204-S208).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.