Abstract: A heat exchanger includes a plate fin, a first flat tube intersecting with the plate fin, and a second flat tube opposed to a flat tube lower surface of the first flat tube, the second flat tube being spaced from the first flat tube and arranged so as to intersect with the plate fin. A flat tube windward lateral surface of the first and second flat tubes is located on an inner side of a peripheral edge of the plate fin, which includes an elevated portion formed between the first and second flat tubes and is located between a first imaginary plane, connecting the flat tube windward lateral surface of the first and second flat tubes, and a second imaginary plane, connecting a center of the flat tube lower surface of the first flat tube and a center of the flat tube upper surface of the second flat tube.

Abstract: A heat exchanger, including plural flat tubes arranged in a right-and-left direction orthogonal to a front-and-back airflow direction of the heat exchanger, a corrugated fin sandwiched by adjacent of the flat tubes and thermally connected thereto at each of apexes of the corrugated fin, an inlet header connected to one end of each of the flat tubes, and an outlet header connected to the other end of each of the flat tubes, the flat tubes extending along an up-and-down direction of the heat exchanger. The corrugated fin includes a protruding portion protruding to a front side with respect to a front-side end portion of each of the flat tubes, the protruding portion including a first lug portion oriented obliquely to the front-and-back direction, a second lug portion being formed in the right-and-left direction at a part sandwiched by the adjacent of the flat tubes.

Abstract: A corrugated fin heat exchanger includes: a first flat tube; a second flat tube aligned in parallel with the first flat tube; and a corrugated fin disposed between the first flat tube and the second flat tube, and the corrugated fin includes a first slant portion bridging between the first flat tube and the second flat tube and inclined relative to a perpendicular line toward the first flat tube at a first angle of inclination, a second slant portion bridging between the first flat tube and the second flat tube and inclined relative to the perpendicular line at a second angle of inclination, and a third slant portion bridging between the first flat tube and the second flat tube, the third slant portion positioned between the first slant portion and the second slant portion, and inclined relative to the perpendicular line at an angle of inclination larger than both of the first angle of inclination and the second angle of inclination.

Abstract: A heat exchanger includes fins that are arranged in a direction orthogonal to a direction in which air flows and a heat transfer pipe that extends through the fins and that is bonded and fixed to the fins when the heat transfer pipe is radially expanded by a pipe-expanding method. Tall projections and short projections are provided on an inner surface of the heat transfer pipe. The tall projections are arranged in a circumferential direction and extend in an axial direction of the heat transfer pipe. The short projections are arranged between the tall projections and extend in the axial direction. Opposing side surfaces of the tall and short projections after the expansion of the heat transfer pipe are so inclined that when extensions are drawn from the side surfaces, the extensions cross each other in an inner region of the heat transfer pipe.

Abstract: In a heat exchanger, a first heat exchange unit is formed by curving a third heat exchange unit having a planar shape through L-shape bending, and a second heat exchange unit is formed by curving a fourth heat exchange unit having a planar shape through the L-shape bending, independently of the third heat exchange unit. The first heat exchange unit and the second heat exchange unit are arranged so as to be opposed to each other along a corner portion between adjacent two side surfaces of a casing.

Abstract: Provided are rectangular plate-like fins 2 layered at intervals; and flat tubes 3 which are perpendicularly extended through the layered plate-like fins 2 and are provided on multiple levels along a longitudinal direction of the plate-like fins 2. The plate-like fins 2 are provided with at least one heat transfer promoting section 6 that is positioned in a region between adjacently-positioned flat tubes 3 and in which ridge sections 4 and valley sections 5 having ridgelines extending in the longitudinal direction of the plate-like fins 2 are arranged to alternate. En the heat transfer promoting section 6, at least one slit 7 allowing communication between a front and a back of the plate-like fin 2 is formed on a downwind side of the ridge sections 4.

Abstract: A heat exchanger is configured such that flat tubes in at least two levels bent or connected to each other at one end in an axial direction of the flat tubes and the flat tubes in at least two columns connected to each other are included in refrigerant passages through which refrigerant flows, and a flow direction of gas is counter to flow of refrigerant through the refrigerant passages in a column direction while the heat exchanger serves as a condenser.

Abstract: An indoor unit for an air-conditioning apparatus includes a main heat exchanger unit and a sub heat exchanger unit, the main heat exchanger unit includes a first main heat exchanger disposed at a front side of a case and a first heat-transfer pipe extending in a vertical direction, and a second main heat exchanger disposed at a back side of the case and a second heat-transfer pipe extending in the vertical direction. The sub heat exchanger unit includes a leeward-side first sub heat exchanger disposed at a leeward side of the first main heat exchanger and a heat-transfer pipe extending in a width direction, and a leeward-side second sub heat exchanger including a heat-transfer pipe extending in the width direction of the case. The leeward-side second sub heat exchanger has a lower end surface located above an air passage wall and is disposed at a leeward side of the second main heat exchanger.

Abstract: A heat exchanger includes at least one flat tube configured to allow a refrigerant mixture inclusive of HFO1123, R32, and HFO1234yf to flow therethrough as a heat medium. The flat tube includes a plurality of flow paths for the heat medium. Each of the plurality of flow paths has a round rectangular shape in cross section, the round rectangular shape being defined by a pair of longitudinal line segments opposed to each other, a pair of lateral line segments opposed to each other, and a set of four rounded corners, each of the rounded corners being a segment of a circumference of a circle. The pair of longitudinal line segments are intersects with the pair of lateral line segments at the rounded corners. The round rectangular shape is configured to satisfy 0.005?r/d?0.8 where r is a radius of the circle, and d is a distance between the pair of longitudinal line segments opposed to each other.

Abstract: An indoor unit for an air-conditioning apparatus includes a case, an air-sending fan, and a heat exchanger unit. The heat exchanger unit includes a plurality of heat-transfer pipes extending in a vertical direction and forming a plurality of refrigerant passages in a width direction of the case and an air flow direction, and a plurality of headers connected to both ends of the plurality of heat-transfer pipes to allow the refrigerant to flow between the plurality of heat-transfer pipes. The plurality of headers include a plurality of division headers dividing and connecting the plurality of heat-transfer pipes arranged in the air flow direction and connecting in parallel the plurality of heat-transfer pipes arranged in the width direction, and a return header connecting and turning back the plurality of divided refrigerant passages arranged in the air flow direction and connecting in parallel the plurality of heat-transfer pipes arranged in the width direction.

Abstract: A distributor includes a main body. The main body includes a refrigerant inflow path, a plurality of refrigerant outflow paths, a distribution path communicating with the refrigerant inflow path and the plurality of refrigerant outflow paths, and a plurality of tapered paths each communicating between corresponding one of the plurality of refrigerant outflow paths and the distribution path. The tapered paths each have an inlet opening and an outlet opening, the inlet opening being larger than the outlet opening.

Abstract: Plate-shaped fins of a heat exchanger each include, at circumferential portions thereof defining a notch in which a heat transfer tube having a flattened shape is disposed, fin collars formed by being raised from the circumferential portions. Each of the fin collars includes, in a position that faces a long axis side surface of the heat transfer tube, at least one reflare section bent in a direction opposite to the side surface. At least one of the reflare sections defining fin pitches between the adjoining plate-shaped fins is formed so that a reflare tip portion, which is a tip portion of the reflare section, is drawn apart from a contact side surface of the plate-shaped fin with which the reflare section comes into contact.

Abstract: A heat exchanger, in which refrigerant causing disproportionation is used, includes a main heat exchange unit including a plurality of first heat transfer pipes arranged side by side, a sub-heat exchange unit including a plurality of second heat transfer pipes arranged side by side, and a relay unit including a plurality of relay passages connecting the plurality of first heat transfer pipes and the plurality of second heat transfer pipes. Each of the plurality of relay passages has one inlet connected to a corresponding one of the plurality of second heat transfer pipes, and a plurality of outlets each connected to a corresponding one of the plurality of first heat transfer pipes. Each of the plurality of relay passages distributes the refrigerant flowing from the one inlet, without merging streams of the refrigerant together, and causes the refrigerant to flow out of the plurality of outlets.

Abstract: The heat exchanger includes heat exchange units. Each of the heat exchange units includes a plurality of plate fins and a plurality of flat tubes. The plate fins are arranged spaced apart from one another at intervals so as to allow air to flow therebetween. The flat tubes each have an L shape by bending and inserted through the plate fins so that a refrigerant flows therethrough in a direction in which the plate fins are arranged. The heat exchange units are combined to each other so as to form a rectangular shape. Thus, heat exchange can be efficiently performed by increasing the mounting area.

Abstract: A heat exchanger includes a plurality of heat exchange units each including a plurality of fins arranged at intervals such that air passes between adjacent fins and a plurality of heat transfer tubes through which a refrigerant flows. The heat transfer tubes extend through the fins in a direction of arrangement of the fins. The heat transfer tubes are arranged at multiple levels in a level direction perpendicular to an air passing direction. The heat exchange units are arranged in multiple rows in a row direction, serving as the air passing direction. The heat exchanger further includes a row straddling header. Refrigerant passages are provided such that the refrigerant flowing from inlets of the refrigerant passages turns in the row straddling header to outlets of the refrigerant passages. The row straddling header has an interior separated into a plurality of chambers arranged in the level direction. The refrigerant passage is isolated for its corresponding chamber.

Abstract: Plate-like fins have notches longer than a longitudinal axis of flat tubes that are placed in the notches. The plate-like fins also have bend portions that are located on projections projecting toward the edges more than the ends of the flat tubes, are formed by bending part of the plate-like fins, erect in a stacking direction in which the plate-like fins are stacked, and are in contact with adjacent ones of the plate-like fins. The height of the bend portions in the stacking direction is the length of a predetermined spacing.

Abstract: A refrigeration cycle apparatus avoids refrigerant conditions causing a disproportionation reaction and exhibit high performance with safety even when a refrigerant causing the disproportionation reaction is used in a zeotropic refrigerant mixture. The refrigeration cycle apparatus uses, as a working refrigerant, the zeotropic refrigerant mixture of a first refrigerant and a second refrigerant having a higher boiling point than that of the first refrigerant under the same pressure, and includes at least a main passage sequentially connecting a compressor, a first heat exchanger, an expansion valve, a gas-liquid separator, and a second heat exchanger. The first refrigerant causes the disproportionation reaction.

Abstract: A heat exchanger includes a plurality of plate-shaped fins arranged at intervals such that air flows between adjacent fins, each of the fins having insertion holes and a plurality of flat tubes extending through the fins such that a refrigerant flows through the tubes in a stacking direction of the fins, each flat tube having a cross-section having straight long sides and half-round short sides, each flat tube having long-side outer circumferential surface parts and a short-side outer circumferential surface part in contact with the fin and covered with the brazing filler metal. The fins and the flat tubes are joined with the brazing filler metal covering the outer circumferential surfaces of the flat tubes such that top part of each fin collar of each fin is in contact with the flat tube and base part of the fin collar is spaced apart from the flat tube.

Abstract: A refrigeration cycle apparatus includes refrigerant circuits each configured to circulate a refrigerant of the same composition. The refrigerant circuit is provided with a radiator configured to condense the refrigerant to transfer heat to external fluid, and the refrigerant circuit is provided with a radiator configured to transfer heat to the external fluid while allowing the refrigerant to be maintained in a supercritical state. The radiator is arranged upstream of the radiator in a direction of a flow of the external fluid. A capacity of a refrigerant flow channel of the radiator is smaller than a capacity of a refrigerant flow channel of the radiator.

Abstract: An air-conditioning apparatus includes an outdoor unit equipped with an outdoor-side heat exchanger formed by inserting a plurality of heat transfer pipes made of a metal material, such as aluminum or an aluminum alloy, into a plurality of fins, and an indoor unit equipped with an indoor-side heat exchanger formed by inserting a plurality of heat transfer pipes made of a metal material, such as aluminum or an aluminum alloy, into a plurality of fins. The heat transfer pipes in the outdoor-side heat exchanger are each internally provided with a plurality of straight grooves substantially parallel to the pipe axial direction. The heat transfer pipes in the indoor-side heat exchanger are each internally provided with a plurality of spiral grooves having a predetermined lead angle.