Transmission park control system
US10408347B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 2017 |
| Grant date | Sep 10, 2019 |
| Priority date | — |
| Expiry date | Jan 19, 2038 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K11/0712
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A park valve performs a multi-plexing function in which an out-of-park circuit is connected to line pressure when the valve is in an out-of-park position and is vented when the valve is in a park position. When particular clutches are released, the out-of-park circuit biases the park valve toward the out-of-park position. To initiate engagement of park, a controller commands a low line pressure, reducing the forces that bias the park valve toward the out-of-park position. Once the valve reaches an intermediate position in which the line pressure circuit is no longer fluidly connected to the out-of-park circuit, the controller commands an increase in line pressure, increasing the forces that bias the park valve toward the park position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.