Abstract: An exhaust heat recovery structure includes a first pipe through which exhaust gas from an engine flows; a second pipe that branches from the first pipe, the second pipe including a heat exchanger that implements heat exchange with the exhaust gas; and an opening and closing valve provided at the first pipe, the opening and closing valve adjusting flow amounts of the exhaust gas flowing into the second pipe, wherein the first pipe includes a first pipe body and a second pipe body that, are adjacent in a flow direction of the exhaust gas, and a join portion between the first pipe body and the second pipe body is provided along a circumferential direction of the first pipe.

Abstract: A heat exchanger comprises a plurality of heat exchange segments juxtaposed in a housing, and a plug member connected fluid-tightly to the housing, and supporting the heat exchange segments to provide a coolant or cooling medium passage in each gap between the heat exchange segments adjacent to each other. Each heat exchange segment comprises a case having an opening only on a surface of the case, at least outside of the opening being plugged fluid-tightly by the plug member, and a guide member, e.g., fin accommodated in the case, and provided with a plurality of passages allowing only gas flow in a predetermined direction, and gas intake passages and gas exhaust passages at the upstream and downstream thereof, wherein an opening of the case is provided with a gas inlet port communicated with the gas intake passage, and a gas outlet port communicated with the gas exhaust passages.

Abstract: A heat exchanger comprises a plurality of heat exchange segments juxtaposed in a housing, and a plug member connected fluid-tightly to the housing, and supporting the heat exchange segments to provide a coolant or cooling medium passage in each gap between the heat exchange segments adjacent to each other. Each heat exchange segment comprises a case having an opening only on a surface of the case, at least outside of the opening being plugged fluid-tightly by the plug member, and a guide member, e.g., fin accommodated in the case, and provided with a plurality of passages allowing only gas flow in a predetermined direction, and gas intake passages and gas exhaust passages at the upstream and downstream thereof, wherein an opening of the case is provided with a gas inlet port communicated with the gas intake passage, and a gas outlet port communicated with the gas exhaust passages.