Speed ratio controller and control method of automatic transmission
US6135917A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 22, 1999 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Jul 22, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/6644
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A speed ratio controller for a continuously variable transmission comprises a sensor (66) for detecting the activation of a catalyst purifying the exhaust gas of the engine, a sensor (62) for detecting an engine load, a sensor (63) for detecting a vehicle speed and a microprocessor (61) for controlling the transmission. The microprocessor (61) stores a first speed change map defining a speed ratio of the transmission according to the vehicle speed and engine load, and a second speed change map defining a larger speed ratio than the speed ratio defined in the first speed change map in a range where the vehicle speed is lower than a predetermined vehicle speed and the engine load is lower than a predetermined engine load. In order to determine the speed ratio of the transmission, the microprocessor (61) applies the first speed change map until the catalyst is activated and the second speed change map after the catalyst is activated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.