Adaptable gas and moisture shield for a gas management valve

Abstract

A shield for a gas management pintle valve, such as an exhaust gas recirculation valve for an internal combustion engine, for mitigating leakage of gas and moisture along the valve pintle into the actuator, to prevent corrosion and failure of the actuator. The shield is a tubular member having an equatorial radial flange and is slidably mounted on the pintle in an annular chamber between the valve body and the actuator. The inner diameter of the tube is selected to be as close-fitting to the pintle as possible while still being slidable thereupon to be adapted to either of two operating positions. During engine shutdowns, the shield is drawn by gravity toward the valve body to form a first seal with the flange against the pintle bearing or a bearing splash shield, preventing or minimizing the escape of moist, hot gases under low pressure from the valve along the pintle. During engine running, high-pressure exhaust gases within the valve may be forced along the pintle through the bearing bore and bearing splash shield toward the actuator. The gases force the shield to slide along the pintle, opening the first seal and forming a second seal with the flange against the actuator, allowing the leaked gases to escape radially from the pintle without invading the actuator.