Clutch return spring pressure learning during a coasting maneuver
US8831844B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jul 27, 2012 |
| Grant date | Sep 9, 2014 |
| Priority date | — |
| Expiry date | Dec 12, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/60
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method of learning the return spring pressure of a clutch in a vehicle having an engine and an automatic transmission includes selecting a clutch for analysis from a plurality of clutches of the transmission when the vehicle coasts for a predetermined duration. The method includes ramping down clutch pressure to the selected clutch until engine speed reaches idle and measuring the clutch pressure for the selected clutch after engine speed has remained at idle for a calibrated duration. An actual return spring pressure may be calculated as a function of the preliminary return spring pressure. The actual return spring pressure may be used thereafter to control a subsequent shift event of the transmission. A vehicle includes an engine, transmission, and controller configured to detect a predetermined coasting condition, and to execute code using a processor to thereby execute the above method. A system includes the transmission and controller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.