Power downshift clutch control
US9249881B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 23, 2015 |
| Grant date | Feb 2, 2016 |
| Priority date | — |
| Expiry date | Feb 23, 2035 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2306/24
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A method of controlling clutches in a multi-speed transmission includes beginning a current shift from a starting gear to an initial target gear, and determining whether the current shift is a downshift. The method determines jump-stage eligibility of a first clutch. Determining jump-stage eligibility includes determining whether the first clutch is a holding clutch for the current shift, and determining whether the first clutch is an off-going clutch for a legal shift from the initial starting gear to an adjusted target gear having a higher speed ratio than the initial starting gear. If the first clutch is not jump-stage eligible, the method maintains pressure of the first clutch at a current pressure. If the first clutch is jump-stage eligible, the method reduces the pressure of the first clutch from the current pressure to a staging pressure, which is greater than a slipping pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.