A heat exchanger includes: flat pipes each including a passage for refrigerant that are arranged side by side in a predetermined step direction; and a header collecting pipe extending along the predetermined step direction that is connected to the flat pipes. The header collecting pipe includes: a flat pipe-side header forming member; and an opposite-side header forming member facing the flat pipe-side header forming member. The flat pipes are inserted in the flat pipe-side header forming member and an internal space exists between the flat pipe-side header forming member and the opposite-side header forming member. When viewed along the predetermined step direction: the flat pipe-side header forming member has a flat pipe-side curved portion protruding toward the flat pipes and the opposite-side header forming member has an opposite-side curved portion protruding toward a side away from the flat pipes.

A rapid heat dissipation device is provided to use for a heat source, and includes a heat conducting plate, a heat dissipating fin group, one or a plurality of heat pipes and a siphon heat-dissipating device. The heat conducting plate is thermally attached to the heat source. The heat dissipating fin group is arranged on one side of the heat conducting plate. One end of the heat pipe is fixed to the heat conducting plate, and another end is fixed to the heat dissipating fin group. The siphon heat-dissipating device is stacked above the heat pipe, and one end is fixed to the heat-conducting plate and another end is fixed to the heat-dissipating fin group. Through the siphon heat-dissipating device overlapping up and down with the heat pipe and having the same direction to achieve uniformly heat dissipating and cooling.

A heat exchanger (5) comprises: a plurality of flat tubes that are stacked in a direction perpendicular to a refrigerant flow direction, and a plurality of fins (111) that have a first flat tube among the plurality of flat tubes, a second flat tube adjacent to the first flat tube, a first flat tube insertion portion (113A) into which the first flat tube is inserted, and a second flat tube insertion portion (113B) into which the second flat tube is inserted. A first fin (111) has, formed on the inner periphery of the first flat tube insertion portion (113A), a cut and raised piece (114) for spacing a fin pitch (P) between the first fin (111) and an adjacent second fin (111). The cut and raised piece (114) has a raised portion of the same length as the fin pitch (P), and a folded portion that is folded back at the tip of the raised portion and that is in contact with the second fin (111).

A heat exchanger includes plate-shaped fins and a plurality of heat transfer pipes attached to the fins so as to intersect the fins. The heat transfer pipes are disposed at intervals in a long-edge direction of the fins. The fins have a wave shape at at least a portion thereof and are capable of expanding and contracting in the long-edge direction.

An air conditioner includes a heat exchanger that is arranged in a ventilation flue inside a housing, wherein the heat exchanger includes a plurality of flat tubes, and a fin that includes a plurality of notch portions arranged side by side in a vertical direction, to which the plurality of flat tubes are inserted, and includes intermediate regions each formed between two of the notch portions adjacent to each other in a vertical direction, and a connection region connecting the intermediate regions to each other, first bulging portions that are at least partly positioned on the intermediate regions, and a second bulging portion that overlaps with a gap generated between the first bulging portions and the flat tubes.

A heat exchanger includes heat transfer tubes and a header that forms a refrigerant flow path. The header includes: a first member that includes a first plate-shaped portion; a second member that includes a second plate-shaped portion; a third member that includes a third plate-shaped portion positioned between the first plate-shaped portion and the second plate-shaped portion in a first direction that is a direction in which the first plate-shaped portion and the second plate-shaped portion are arranged; a fourth member that includes a fourth plate-shaped portion positioned between the first plate-shaped portion and the second plate-shaped portion in the first direction and a second opening that constitutes a part of the refrigerant flow path, where a second is along a longitudinal direction of the second opening; and a fifth member.

A heat exchanger connected to a refrigerant pipe includes: heat transfer tubes; and a header that connects the refrigerant pipe and the heat transfer tubes, and that forms a refrigerant flow path between the refrigerant pipe and the heat transfer tubes. The header includes a first member that includes a first plate-shaped portion, and a second member that includes a second plate-shaped portion that is stacked on a heat transfer tubes side of the first plate-shaped portion. The first plate-shaped portion has a first opening that forms the refrigerant flow path. The second plate-shaped portion has a second opening that forms the refrigerant flow path. When viewed in a stacking direction of the first plate-shaped portion and the second plate-shaped portion, the second opening and the first opening overlap each other at a first region and at a second region that is different from the first region.

A heat sink assembly with heat pipe includes at least one aluminum fin assembly and at least one copper heat pipe, which are made of dissimilar metal materials. The aluminum fin assembly includes at least one area to be connected to other members of the heat sink assembly, such as a groove. A copper embedding layer is provided on a groove inner surface of the groove for connecting the aluminum fin assembly to the copper heat pipe. By providing the copper embedding layer, the connection between the aluminum fin assembly and the copper heat pipe made of dissimilar metal materials is improved, and the problems of eutectic grains formed on the surface of the aluminum fin assembly and environmental pollution caused by electroless nickel plating are eliminated.

A heat exchanger includes a flat tube and a plurality of fins. The plurality of fins are arranged on the flat tube and inclined with respect to a longitudinal direction of a cross section perpendicular to an axis of the flat tube. The plurality of fins may be inclined at different angles with respect to the axis of the flat tube. The flat tube may include a straight portion on which the plurality of fins are arranged, and a bend on which at least one fin other than the plurality of fins is arranged. The at least one fin extends perpendicularly to the axis of the flat tube.

A heat exchanger in which a refrigerant and air flow exchange heat includes a first heat-exchanging unit. The first heat-exchanging unit includes: a first header including a first gas refrigerant inlet/outlet; a second header including a first liquid refrigerant inlet/outlet; a plurality of first flat tubes disposed side by side in a longitudinal direction of the first header and the second header; and a first communication path formation portion that is connected to the first header and the second header and that forms a first communication path.