Electronically actuated transmission range control system
US6139468A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 1999 |
| Grant date | Oct 31, 2000 |
| Priority date | — |
| Expiry date | Apr 15, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S477/906
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An automatic transmission control system having gearing that establishes multiple forward driving ratios and a reverse ratio as well as a neutral mode, an electrohydraulic control valve circuit for controlling the application and release of clutch and brake elements for the transmission gearing, a driver-controlled range selector for transmitting operator commands to shift control logic, and a failure mode management circuit that monitors the shift control logic and the response of the transmission system to operator commands, as well as the transmission range selector signals delivered to the shift control logic whereby multiple control redundancies in the electronic range control system ensure that system failures and component failures develop an error signal to alert the driver of possible malfunctions during the range selection period. Range feedback information from the transmission and system validation for the electronic microprocessor output commands when multiple error signals are present will result in a neutral default state for the transmission.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.