Noise-reducing IC engine exhaust valve - has projection for affecting gas flow situated near seating surface or on stem near head

摘要

The IC engine exhaust valve is basically conventional, with a head embodying the seating surface, an adjoining conical portion and a stem. Between the seating surface and stem, it has a projection which affects the gas flow. The projection may be a step on the conical portion, close to the seating surface. Alternatively it may be a relatively sharp-edged ring on the valve stem near that portion, shrunk on or formed by upsetting.