Electronic transmission control system with fail-safe system for automotive vehicle with continuously variable automatic transmission
US6077187A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1998 |
| Grant date | Jun 20, 2000 |
| Priority date | — |
| Expiry date | Jul 9, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S477/906
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An electronic transmission control system having a fail-safe system for an automotive vehicle with a continuously variable automatic transmission whose speed-change ratio is changeable continuously depending on vehicle speed and engine load, comprises a hydraulic modulator producing at least a regulated line pressure necessary to adjust the speed-change ratio hydraulically, a desired speed-change ratio arithmetic processing section for calculating a desired speed-change ratio based on the vehicle speed and the engine load, and a desired line pressure arithmetic processing section for calculating a desired line pressure based on the desired speed-change ratio and the engine load. Also provided is a fail-safe section comprises a comparing portion for comparing the desired line pressure to a predetermined line pressure threshold above which the desired line pressure is within an unreasonably high line pressure zone, a decision portion for deciding on the basis of a result of comparison of the comparing portion whether the desired line pressure is above the predetermined line pressure threshold, and a speed-change ratio retaining portion for retaining the speed-change ratio of the cont…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.