Hydraulic control device for automatic transmission
US8123642B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 2009 |
| Grant date | Feb 28, 2012 |
| Priority date | — |
| Expiry date | Sep 20, 2030 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H3/663
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic control device for an automatic transmission, including: a hydraulic pressure source; a plurality of friction engagement elements; a line pressure regulating valve that regulates hydraulic pressure from the hydraulic pressure source to a predetermined line pressure; a plurality of operation pressure regulating valves that regulate the line pressure as operation pressure for a hydraulic servo operating a friction engagement element; a maximum pressure conducting circuit that feeds a maximum pressure, among the operation pressures, to the line pressure regulating valve, wherein the friction engagement elements are engaged and released to achieve a plurality of forward speeds and a reverse speed, and the line pressure regulating valve regulates the line pressure during forward travel based on the maximum operation pressure, and regulates the line pressure during reverse travel based on the operation pressure input from a specific operation pressure regulating valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.