Control apparatus for vehicular automatic transmission
US7524267B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2006 |
| Grant date | Apr 28, 2009 |
| Priority date | — |
| Expiry date | Jun 29, 2027 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/1232
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In a hydraulic control apparatus for a vehicular automatic transmission, if it is determined that there is a failure that may cause tie-up in an automatic transmission, communication is provided between a first output port and a first drain port in a switching valve. As a result, a hydraulic frictional engagement device, which should be disengaged when there is a failure, is disengaged. Also, a specific shift speed is achieved by controlling the switching valve. Therefore, it is not necessary to select a shift speed that is achieved on the condition that the hydraulic frictional engagement device, which should be disengaged when there is a failure, is engaged. Thus, it is possible to prevent a shift that may impair driveability when there is a failure that may cause tie-up in the automatic transmission.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.