Method and apparatus for synchronizing low to high transfer case shifts
US5771477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | May 10, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H59/46
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for operating a power transfer device such as a vehicle transfer case having, shaft speed sensors, a two speed (high-low) drive assembly, an electrically, pneumatically or hydraulically operated shift operator and a microprocessor comprising the steps of sensing the speeds of the transfer case input shaft and output shaft, calculating the rate of change (.DELTA.S/.DELTA.t) of the speed of the input shaft, predicting, based upon such rate of change, a time when the input shaft and the output shaft will be synchronized and commencing movement of such shift operator at a time prior to such synchronization in order to effect engagement of such clutch into high gear at substantially the instant of synchronization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.