Abstract: A core unit of a heat exchanger is composed of a plurality of parallel flat tubes, a plurality of corrugated fins, a support member disposed between two of the corrugated fins and an electric heater disposed inside the support member. The support member has a pair of parallel plates bonded to the corrugated fins at the summits of corrugation of the corrugated fins. The electric heater is composed of a heating element and an insulation member inserted between the heating element and the parallel plates.

Abstract: An air conditioning apparatus includes a heating heat exchanger for heating air blown toward a passenger compartment using hot water as a heating source. A plurality of electric heating members are formed integrally with the heating heat exchanger, and electric power supplied to the electric heating members is controlled according a temperature of the hot water. Therefore, a number of the electric heating members to be operated is finely controlled according to the temperature of water flowing through the heating heat exchanger. Further, when a water temperature of the heating heat exchanger is lower than a predetermined temperature (e.g., 35.degree. C.), a water valve is closed to interrupt the flow of water to the heating heat exchanger, and a blower is operated. Therefore, a quantity of heat transmitted from the electric heating members to the water in the heating heat exchanger can be greatly decreased.

Abstract: A heat-exchanging core portion includes a plurality of tubes arranged in parallel and a plurality of fin members disposed between a pair of adjacent tubes. While an electric heat emitting unit is constructed by supporting a heat emitting body including a heat emitting element inside a frame through a fin member. The electric heat emitting unit is installed into a space, which is defined in the heat-exchanging core portion, having a predetermined distance after the heat-exchanging core portion is assembled and integrally brazed while defining the space.

Abstract: An inner half cylinder and an outer half cylinder are brazed to each other to form a cylindrical header tank. Both ends of tubes are connected to the inner half cylinder. An opening of the outer half cylinder is communicated with an opening of a joint pipe. A tongue portion which is provided on the periphery of the opening of the outer half cylinder is inserted and curled in the opening of the joint pipe so as to fix the joint pipe on the outer half cylinder firmly.

Abstract: A header has a tank member having a transverse cross-section of a circular arc shape, and a tube attachment member having a transverse cross-section flatter than the above-mentioned circular arc shape as a whole, are opposed and joined. The tube attachment member has identical curvature portions constituted with an inner diameter R2 which is the same as the inner diameter R2 of the tank member at both sides to be joined to the tank member, and has a large curvature portion constituted with an inner diameter R1 which is larger than the inner diameter R2 of the tank member at an intermediate portion interposed between the identical curvature portions. A connecting position P between the identical curvature portion and the large curvature portion is inside from both edges of a tube.

Abstract: A device for preventing creep between an annular member and a partner member holding the annular member includes a resilient ring member fitted within a circumferential groove formed eccentrically in the annular member. The resilient ring member has at least one bulged portion provided with a height extending beyond the circumferential groove, and has a thickness greater than the depth of the circumferential groove.