Adaptive transmission pressure control with run-through detection
US5289741A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 1992 |
| Grant date | Mar 1, 1994 |
| Priority date | — |
| Expiry date | Jun 8, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/0087
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An improved adaptive line pressure control which detects the occurrence of run-through and overrides the normal adaptive pressure control in response to a detected run-through condition so that the line pressure during subsequent shifting is increased instead of decreased. A run-through condition is detected by periodically sampling the transmission speed ratio in the course of the inertia phase of an upshift from a lower speed ratio to an upper speed ratio, and determining the average ratio for the upshift. If the average ratio is within a reference amount of the normal value (ratio midpoint), the adaptive control is allowed to update the adaptive pressure value in relation to the difference between the measured shift time and a desired shift time. If the average ratio exceeds the normal value (midpoint) by more than the reference amount, a run-through is detected, and the adaptive pressure amount is increased regardless of the measured shift time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.