Control apparatus and method for automatic transmission
US8249786B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 3, 2009 |
| Grant date | Aug 21, 2012 |
| Priority date | — |
| Expiry date | Nov 21, 2030 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2057/0012
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A control apparatus for an automatic transmission includes a shift control section configured to perform a shift of the automatic transmission; and a judder judging section. The shift control section is configured to judge whether or not a progress of the shift is during an inertia phase. The judder judging section calculates a characteristic-gradient index value which is a value obtained by quantifying a phenomenon that appears as a relative rotational speed between input and output of the first friction-engagement element becomes reduced with a progress of the inertia phase. The phenomenon appears in a different way in dependence upon whether a relational characteristic of a friction coefficient of the first friction-engagement element with respect to the relative rotational speed is a positive-gradient characteristic or a negative-gradient characteristic. The judder judging section determines that the judder has occurred based on the characteristic-gradient index value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.