Exhaust gas heat exchanger

An exhaust gas heat exchanger comprising:

• a housing,
• a tube bundle composed of exhaust-gas tubes positioned in said housing,
• a cooling circuit for circulating a coolant fluid around the exhaust gas tubes,
• a bypass passage located in said housing, wherein the tube bundle and the bypass passage open into a common exhaust gas inlet region and also in a common exhaust gas outlet region,
• a selectively actuatable exhaust gas valve comprising a moveable closure member arranged in either the inlet region or the outlet region for guiding the flow of exhaust gas selectively through the tube bundle or the bypass passage,
• wherein the closure member is designed as a pivot flap that includes a second half-flap, such that the two half-flaps for a pivot flap with an approximately centrally arranged pivot axle along the drive shaft and with two opposite sealing edges, and further comprising a partition with a concave sealing surface facing the pivot flap arranged between the pivot axle and the partition wall, and
• wherein one sealing edge slides along the sealing surface over a pivoting range of the pivot flap.

An exhaust gas heat exchanger comprising:

• a housing,
• a tube bundle composed of exhaust-gas tubes positioned in said housing,
• a cooling circuit for circulating a coolant fluid around the exhaust gas tubes,
• a bypass passage located in said housing, wherein the tube bundle and the bypass passage open into a common exhaust gas inlet region and also in a common exhaust gas outlet region,
• a selectively actuatable exhaust gas valve comprising a moveable closure member arranged in either the inlet region or the outlet region for guiding the flow of exhaust gas selectively through the tube bundle or the bypass passage, wherein the closure member comprises a flexurally rigid, pivotable half-flap having one longitudinal side secured to a drive shaft that is arranged transversely with respect to the exhaust gas flow, and
• a separate partition wall extending in the direction of exhaust gas flow between the drive shaft and the tube cross sections of the tube bundle, and separating the bypass passage from the flow passages of the exhaust gas tubes.

An exhaust gas heat exchanger comprising:

• a housing,
• a tube bundle composed of exhaust-gas tubes positioned in said housing,
• a cooling circuit for circulating a coolant fluid around the exhaust gas tubes,
• a bypass passage located in said housing, wherein the tube bundle and the bypass passage open into a common exhaust gas inlet region and also in a common exhaust gas outlet region,
• a selectively actuatable exhaust gas valve comprising a moveable closure member arranged in either the inlet region or the outlet region for guiding the flow of exhaust gas selectively through the tube bundle or the bypass passage, and
• an actuating drive comprising a vacuum cell and an actuating member operatively connected to the vacuum cell for driving the closure member.