Image Number 3 for United States Patent #6390053.
An internal combustion engine includes an engine housing that defines a main combustion chamber separated from a precombustion chamber by a flame communication passage way. A source of gaseous fuel is fluidly connected to one end of a fuel supply passage. A check valve, which includes a valve body with a valve seat, and a valve member, is positioned between the other end of the fuel supply passage and the precombustion chamber. The valve member is moveable between an open position and a closed position. The valve body and the valve member define a fluid passage that fluidly connects the fuel supply passage to the precombustion chamber when the valve member is in its open position. The valve body and the valve member substantially fluidly isolate the valve seat from the precombustion chamber when the valve member is in its closed position.