Hydraulic control system for automatic transmission of vehicle
US9822872B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jul 29, 2016 |
| Grant date | Nov 21, 2017 |
| Priority date | — |
| Expiry date | Jul 29, 2036 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/1252
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic control system of an automatic transmission may be applied to an automatic transmission in which a reverse speed stage is engaged by engagement of first and second friction elements. The hydraulic control system may include: a first solenoid valve being a normally open type and controlling a line pressure to generate a first hydraulic pressure; a second solenoid valve being a normally closed type and controlling the line pressure to generate a second hydraulic pressure; first and second switch valves, the first switch valve selectively supplying the first hydraulic pressure to the second switch valve; and a fail-safe valve selectively supplying the first hydraulic pressure or the second hydraulic pressure to the second friction element, wherein the second switch valve selectively supplies the first hydraulic pressure supplied from the first switch valve or a reverse speed pressure to the first friction element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.