Speed change control apparatus for an automatic transmission
US5743826A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 18, 1996 |
| Grant date | Apr 28, 1998 |
| Priority date | — |
| Expiry date | Jan 18, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/0488
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A speed change control apparatus for an automatic transmission includes a transmission control unit for controlling gear-changing. The control unit discriminates a fluid temperature/rotational speed zone based on the hydraulic fluid temperature and the engine speed at the start of gear-changing, and detects a time period from the end of dead-stroke elimination of an engagement-side hydraulic clutch to the start of actual gear-changing. In the case that a condition for executing learning correction is satisfied and if a time period from the end of the dead-stroke elimination to the start of the actual gear-changing is longer than an upper limit, the control unit increases a learning-correction time with which a dead-stroke-elimination time for the discriminated temperature/speed zone is calculated. The learning-correction time is decreased if such a time period is shorter than a lower limit. By carrying out the learning correction for various temperature/speed, occurrences of degraded shift response and shift shocks resulting from the presence of individual difference of the automatic transmission and an increase or decrease in the engine speed or fluid temperature can be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.