HEAT EXCHANGER

PROBLEM TO BE SOLVED: To ensure heat exchanger performance irrespective of variations in brazing in a heat exchanger having a plurality of partitions in annular space, especially low in height, by providing a terminal structure for ensuring the passage of the annular space and thus preventing the passage of the annular space, serving as a second fluid passage, from being clogged. SOLUTION: At a first opening 4a having a small diameter portion 6 and a large diameter portion 7 into a branch pipe 4 in an axial direction of an outer tube 3, an outer tube terminal 3a is projected to the large diameter portion 7. With a space 8 much wider than clearance to the small diameter portion 6 defined around the outer tube 3, even if much brazing material 9 flows into the branch pipe 4 when the first opening 4a is brazed, the brazing material 9 reaches the large diameter portion 7, which disables seeping capillarity to prevent it from reaching the outer tube terminal 3a. A carbon dioxide passage is thus ensured without brazing material clogging even through a finned annular space susceptible to brazing material clogging, especially low in height. COPYRIGHT: (C)2007,JPO&INPIT