Avoiding coasting downshift torque reversal in an automatic transmission
US8398516B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 2007 |
| Grant date | Mar 19, 2013 |
| Priority date | — |
| Expiry date | Jan 14, 2031 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2342/04
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method for controlling a coast down downshift that is produced in an automatic transmission by disengaging an off-going control element and engaging an oncoming control element, including the steps of determining a first desired pressure magnitude of the off-going control element and a first desired pressure magnitude of the oncoming control element, executing the current downshift using said first desired pressure magnitudes, determining during execution of the current downshift corrections of said first desired pressure magnitudes that occur during the current downshift, determining a second desired pressure magnitude of the off-going control element and a second desired pressure magnitude of the oncoming control element, using said corrections and the second desired pressure magnitude to determine a subsequent desired pressure magnitude of the off-going control element and a subsequent desired pressure magnitude of the oncoming control element, and executing a downshift using said subsequent desired pressure magnitudes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.