Automatic fluid draining from a hydraulic system component of an automatic transmission
US6944529B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 12, 2003 |
| Grant date | Sep 13, 2005 |
| Priority date | — |
| Expiry date | Dec 25, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7762
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
In a hydraulic system for an automatic transmission, a method for automatically draining fluid from an oil cooler and related hydraulic lines when power is off to prevent fluid leakage, escape and outflow when they are disconnected from the system. A control system includes a source of relatively high pressure when power is on, an oil cooler, fluid circuit lines for supplying transmission oil to the cooler, a source of low pressure for containing fluid, such as an oil sump, and a valve hydraulically connected to the circuit, high pressure source, and low pressure source, the valve having a first state at which a hydraulic connection through the valve between the circuit and the source of low pressure is closed when power is on, and a second state at which a hydraulic connection through the valve between the circuit and the low pressure source is open when power is off.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.