Patent ID: 8627880

Claim:
An exhaust gas recirculation system cooler, comprising: an exhaust gas inlet connected to and in fluid communication with an inlet chamber; an exhaust gas outlet connected to and in fluid communication with an outlet chamber; a plurality of generally flat exhaust gas pipes extend parallel to each other through a coolant chamber and are in fluid communication with the inlet chamber on one side and to the outlet chamber on an opposite side; a coolant inlet connected to and in fluid communication with the coolant chamber; and a coolant outlet connected to and in fluid communication with the coolant chamber, wherein the exhaust gas pipes include a plurality of outwardly projecting protrusions spaced apart from each other in a longitudinal direction of the exhaust gas pipes, wherein the protrusions of one exhaust gas pipe bear directly against an adjacent exhaust gas pipe at a distance in the longitudinal direction of the exhaust gas pipes from the nearest protrusion of the other exhaust gas pipe; wherein the exhaust gas pipes have a plurality of inwardly projecting depressions on opposite sides, such that the depressions are at a distance from each other in the longitudinal direction of the exhaust gas pipes; wherein the protrusions of one exhaust gas pipe bear against the other exhaust gas pipe in a region of at least one depression of the other exhaust gas pipe.