Hydraulic controlling apparatus for automatic transmission for vehicle
US7611434B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 2006 |
| Grant date | Nov 3, 2009 |
| Priority date | — |
| Expiry date | Dec 2, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S477/906
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The fail-safe gear step switching valve (120) can be switched to the first position to establish the low-speed side fail-safe gear step (third speed-change gear step) or the second position to establish the high-speed side fail-safe gear step (fifth speed-change gear step). Upon the failure state of the solenoid valve device (SLC1, SLC2), the fail-safe gear step switching valve is held at the second position by the line hydraulic pressure (PL1). Two kinds of the fail-safe gear steps i.e., the third speed-change gear step and the fifth speed-change gear step can be established depending on the vehicle state just before the failure occurrence of the fail-safe gear step switching valve. Even if the D→N operation of the shift lever (72) is performed during the vehicle running in the fifth speed-change gear step, the fail-safe gear step switching valve remains at the second position to establish the fifth speed-change gear step even upon the shifting operation of the shift lever to the “D” position again.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.