Method for controlling a valve for an exhaust system
US7836945B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Feb 19, 2008 |
| Grant date | Nov 23, 2010 |
| Priority date | — |
| Expiry date | Feb 19, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust gas heat exchanger system of a combustion engine has a bypass duct and a heat exchanger duct with a heat exchanger. A valve is controlled by determining when heat is to be transferred from exhaust gas flowing through the exhaust system to the heat exchanger. When heat is to be transferred, the valve is switched into a first position in which all of the exhaust gas flows through the heat exchanger duct. A pressure drop across the heat exchanger system is monitored either directly or indirectly. If the pressure drop reaches a predefined limit, the valve is switched into an intermediate position, resulting in a smaller portion of the exhaust gas flowing through the heat exchanger duct than when the valve is in the first position and a remaining portion flowing through the bypass duct, thereby reducing the pressure drop across the heat exchanger system. If the pressure drop again reaches a predefined limit, the valve is switched into a second position, resulting in an even smaller portion of the exhaust gas flowing through the heat exchanger duct, thereby further reducing the pressure drop across the heat exchanger system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.