20110297862 | Valve flap device - A valve flap device for an exhaust system of a motor vehicle, having at least one tubular valve housing with a flow cross section running perpendicular to a central axis and being formed by the inner geometry and a shaft which can turn about a valve axis with a valve flap mounted on the shaft, being mounted in the valve housing to close the flow cross section. The valve flap device can be made with low material input and at the same time with low fabrication expense at low costs. For this, the valve housing is made from a tubular blank of sheet metal with a tube diameter that is calibrated to the flow cross section at least partially by mechanical, plastic forming. | 12-08-2011 |