Patent ID: 7984753

Claim:
A heat exchanger for performing heat exchange between a first fluid and a second fluid, comprising: a plurality of tubes, each of the tubes defining a first fluid passage therein for allowing the first fluid to flow and including tube main walls, wherein at least one of the tube main walls of each tube includes a projection and a recess, the projection projects in an outward direction of the tube along a peripheral end of the tube main wall, the recess is disposed on the peripheral end of the tube main wall and is recessed from an end of the projection, the plurality of tubes are stacked such that the tube main walls are opposed to each other, spaces are defined between the opposed tube main walls of the adjacent tubes and the projections, and openings are provided by the recesses on side walls of the tubes to be in communication with the spaces; a plate member connected to the plurality of tubes, and including a wall portion and a bulge, wherein the wall portion is disposed along the side walls of the tubes and has an inner surface that closes at least one of the openings such that the space corresponding to the opening closed by the inner surface is closed to provide a thermal insulation space, the bulge expands from the wall portion to define a communication chamber therein, the bulge is defined at a position corresponding to the remaining openings such that the spaces corresponding to the remaining openings are in communication with the communication chamber through the remaining openings and define second fluid passages through which the second fluid flows; and a joint member to be connected to an external circuit through which the second fluid flows, wherein the joint member is connected to the bulge and in communication with the communication chamber.