Method and arrangement for fuel quantity adjustment in connection with downshift
US5754968A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 16, 1995 |
| Grant date | May 19, 1998 |
| Priority date | — |
| Expiry date | Mar 16, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/1926
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The invention relates to an improved method and arrangement for implementing that method, for obtaining in motor vehicles with mechanical stepped gearboxes with automatic gear changing a gentle and quiet engine adjustment during downshifts in normal operating situations and automatically in operating situations where a need for quicker downshifts requires quicker engine synchronisation. In normal operating situations, downshifts involve using only a limited fuel quantity, preferably corresponding to 20% of full-load fuel quantity, in order to raise the engine speed to the synchronous speed for the next gear, resulting in quieter engine adjustment without the occurrence of obvious disturbance of comfort, risk of losing downshifts or safety disadvantages. When there is a need for quicker gear changes, which is detected by any of the following conditions: PA1 accelerator pedal in kick-down position (82), PA1 accelerator pedal operated to more that 60% of full load, combined with activated hill climbing program (81), PA1 engine brake program activated (84), or PA1 too much vehicle deceleration during gear change (86), downshifts involve using a significantly larger fuel quantity (86), …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.