VALVE DEVICE COMPRISING A COVER FLAP AND A THERMAL BRIDGE FOR AN EXHAUST GAS RECIRCULATION SYSTEM AND METHOD FOR THE OPERATION THEREOF

摘要

The invention relates to a valve device (1) for an exhaust gas recirculation system of a combustion engine (3), comprising a flange (2) for flange-mounting to a heat sink having a defined temperature range, especially a water-cooled motor unit (11) of the combustion engine (3). Said device also comprises a first (4a) and a second exhaust gas recirculation pipe (4b) which respectively comprise a first (8a) and a second butterfly valve (8b). Said butterfly valves (8a, 8b) can be rotated by means of a common shaft and are arranged in relation to each other in a bearing device (9) having a bearing housing (12), in such a way that at least one of the exhaust gas recirculation pipes (4a, 4b) can be respectively closed. The inventive device is characterised in that the bearing housing (12) is connected to the flange (2) via a structural thermal bridge (10) in such a way that the bearing housing (12) has a maximum temperature below 400 DEG C, especially below 300 DEG C, during the operation of the combustion engine (3). One such valve device which is especially cheap to produce is guaranteed a long shelf life even when the flow of exhaust gas is at a very high temperature.