Shift control method for an automatic transmission of an automotive vehicle
US5301572A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1993 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Feb 11, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2312/02
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A shift control method for an automatic transmission of an automotive vehicle comprises a preliminary stage which is executed for eliminating the play in mechanism of a low/reverse brake of the automatic transmission at a shifting, particularly at a shifting of the transmission from the neutral position to a running position when the vehicle is at rest, and an engagement stage which is executed subsequently to the preliminary stage for operating the brake substantially. In the preliminary and engagement stages, the fluid pressure supplied to the brake is controlled in accordance with the precontrol pattern and the main control pattern, respectively. The shift control method further comprises a step of correcting a factor defining the precontrol pattern such that the time required from the start of the engagement stage to the start of a substantial shifting of the automatic transmission coincides with an ideal reference time, and a step of correcting the initial value of the fluid pressure supplied to the engaging element at the start of the main control pattern such that the rate of change in the rotational speed of the input shaft of the transmission during the period from the sta…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.