Method of controlling speed reduction ratio for a continuously variable transmissions
US4976169A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 14, 1988 |
| Grant date | Dec 11, 1990 |
| Priority date | — |
| Expiry date | Nov 14, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/19153
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method controlling the speed reduction ratio for a continuously variable speed transmission comprises a running mode control method which is carried out when an accelerator opening is opened, an engine brake mode control method which is carried out when said accelerator opening is substantially closed and a transient control method which is carried out over a predetermined period of time when the control is shifted from a state under the engine brake mode control to a state under the running mode control. The transient control method comprises the steps of obtaining a corrected R-REF engine speed immediately after the shift to the running mode control, by adding a difference between the actual engine speed and the R-REF engine speed to the R-REF engine speed set in correspondence to the current accelerator opening, obtaining a further corrected R-REF engine speed during a predetermined period of time following the shift, by adding a correction which is obtained by gradually decreasing the speed difference with time to the R-REF engine speed, and controlling the speed reduction ratio so that the actual engine speed coincides with the corrected R-REF engine speed over the predeterm…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.