Patent ID: 7958874
Filing Date: 2011-06-14
Classification: F02M

Abstract:
1. An exhaust gas recirculation apparatus for recirculating exhaust gas of an engine from an exhaust passage to an intake passage, the apparatus comprising: an exhaust gas cooler for cooling exhaust gas recirculated to the intake passage; a housing connected with the exhaust gas cooler via a cooler mount face, the housing having a valve chamber communicated with four exhaust ports including inlet and outlet exhaust ports, the inlet and outlet exhaust ports being adjacent to each other and opened in the cooler mount face, the inlet exhaust port communicating with an inlet of the exhaust gas cooler, the outlet exhaust port communicating with an outlet of the exhaust gas cooler; a selector valve rotatably accommodated in the valve chamber for controlling communication among the four exhaust ports; and a rotation axis rotatably supporting the selector valve, wherein the housing has a partition extending from the cooler mount face close to the valve chamber, the partition dividing the inlet and outlet exhaust ports, the housing has a first exhaust passage that includes the inlet exhaust port, for leading exhaust gas from the engine into the exhaust gas cooler through the valve chamber, the housing further has a second exhaust passage that includes the outlet exhaust port, for recirculating exhaust gas, which is cooled in the exhaust gas cooler, to the intake passage through the valve chamber, the housing further has a bypass passage for leading exhaust gas from the engine through the valve chamber to bypass the exhaust gas cooler, the rotation axis is substantially perpendicular to a cooler-mount-face axis passing through a center of the cooler mount face, the rotation axis is offset from a center axis of the exhaust gas cooler and the cooler-mount-face axis of the cooler mount face toward a center axis of the second exhaust passage by a first predetermined offset amount, and the rotation axis is offset to be farther away from the exhaust gas cooler than the partition of the housing by a second predetermined offset amount.