Abstract: An exhaust gas recirculation valve having a reciprocating pintle shaft supported by a sleeve bushing and having a labyrinthine pathway between a valve operating chamber and a shaft/bushing interface to minimize intrusion of exhaust gases into the interface. The labyrinthine pathway is formed between fixed annular elements of the valve body and shaft bushing and a movable annular element of the valve head telescopically disposed between the fixed elements.

Abstract: A relatively simple pressure balanced high flow exhaust gas recirculation (EGR) valve includes an actuator and a separately formed valve assembly retained to the actuator by a deformed lip. The valve body has dual seats controlled by axially spaced heads which are pressure balanced when closed and allow high gas flow when open. The valve body and the associated valve shaft, or portions thereof, are formed of materials having similar coefficients of thermal expansion so that the shaft and body experience similar thermal growth and good seating of the spaced valves is maintained regardless of gas temperature variations. Thickened portions at the valve seats comprise annular ends of a control portion which resist distortion of the seats. The valve body is configured for installation in a cylindrical bore or recess of an associated manifold or other gas passage defining member.