Pressure control system and control method for a multiple-ratio transmission with pre-staged ratio shifts
US6577939B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 2002 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | May 20, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2342/04
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A modular electronic control system for a geared multiple-ratio transmission wherein pressure profiles for each ratio shift actuator are used to provide seamless transitions during both positive and negative engine torque conditions to improve shift feel and responsiveness to ratio change commands. The system provides shift staging for sequenced shifts between ratios as well as for so-called “change-of-mind” shifts in which a sequence shift is interrupted as a new destination gear is introduced. A constant ratio change occurs during sequenced shifts. A change-of-mind shift can be performed directly where the new destination gear is commanded immediately. Independent pressure profiles for each clutch involved in a commanded shift are used to accommodate various types of shifts.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.