Hydraulic control device of automatic transmission
US5971719A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 29, 1998 |
| Grant date | Oct 26, 1999 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H61/0009
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydraulic control device of an automatic transmission is provided wherein three-stage valve bodies are superposed on and fixed to each other with partition plates interposed therebetween, and a pressure regulator valve is mounted in a middle-stage valve body out of the three valve bodies. An inlet oil path that extends from an oil strainer to an inlet port of an oil pump is formed in a lower portion of the valve body. A drain port of the pressure regulator valve communicates with the inlet oil path leading to the inlet port, through a drain hole formed through the partition plate between the middle-stage and lower-stage valve bodies, and a drain hole formed through the low-stage valve body. In this arrangement, the oil drained from the pressure regulator valve is led to the inlet port without passing through the oil strainer, assuring an increased degree of freedom in selecting the position of the pressure regulator valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.