Gearshift control system for automatic transmissions using air flow sensor
US4318312A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 1979 |
| Grant date | Mar 9, 1982 |
| Priority date | — |
| Expiry date | Jun 18, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S477/902
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A gear shift control system for an automatic transmission comprises an air flow sensor for sensing the quantity of air taken into an internal combustion engine and supplying a corresponding electrical signal to a differentiator which provides a derivative of the sensed intake air quantity. A vehicle speed sensor senses the speed of rotation of the engine crankshaft to generate a corresponding signal. A gear shift decision circuit is receptive of signals from the air flow sensor and vehicle speed sensor to define a gear shift control line on a two-dimensional coordinate system as a function of the received input signals on respective coordinate axes. The derivative of the sensed air quantity is used to shift the gear shift control line to a higher speed side of the coordinate system to permit the transmission to effect downshift operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.