Patent ID: 8807122

Claim:
A tank venting apparatus for a supercharged internal combustion engine, comprising a fuel tank, a fuel vapor reservoir connected to the fuel tank by a connecting line and to an inlet manifold of the internal combustion engine by a venting line, a tank venting valve arranged in the venting line, and a safety valve arranged in the venting line between the tank venting valve and the inlet manifold, the safety valve configured to: permit gas flow in an opening direction of the safety valve from the tank venting valve to the inlet manifold when a pressure at the tank venting valve exceeds a pressure at the inlet manifold, permit gas flow in a closing direction of the safety valve from the inlet manifold to the tank venting valve when the pressure at the tank venting valve exceeds the pressure at the inlet manifold by an amount more than zero but less than a predefined amount that closes the safety valve, and close in response to the pressure at the tank venting valve exceeding the pressure at the inlet manifold by more than the predefined amount, thereby preventing gas flow in the closing direction.