Unexpected N logic for vehicular semi-automated mechanical transmissions
US5315514A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1991 |
| Grant date | May 24, 1994 |
| Priority date | — |
| Expiry date | Sep 16, 2011 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T74/1926
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A control method/system (200) for a control system (104) for semi-automatically executing automatically selected upshifts and downshifts of a mechanical transmission system (10) is provided. The control system includes a central processing unit (106) for receiving input signals indicative of transmission input shaft (16) and output shaft (90) speeds (IS, OS) and processing the same in accordance with predetermined logic rule to issue command output signals to a transmission actuator (112, 70, 96) to implement the selected shifts by automatic shifting into neutral upon a naturally or manually caused torque reversal of the transmission and remaining in neutral until the vehicle operator causes substantially synchronous conditions to occur. The method/system (200) includes calculating a first and second reference value (REF-UP, REF-DN) as functions of input shaft speed and only preselecting upshifts of output shaft acceleration (dOS/dt) exceeds the first reference (REF-UP) and only preselecting downshifts if output shaft acceleration (dOS/dt) is less than the second reference value (REF-DN). The first and second reference values vary with the value of input shaft speed over ranges (15…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.