Abstract: The heat exchanger includes a first fluid path unit 10 and a second fluid path unit 9. The first fluid path unit 10 has at least two return flow paths 26, in which a first fluid flows, in opposed relation to each other and which are stacked continuously through folded portions 27, 18. The second fluid path unit 9 with a second fluid flows therein has second fluid paths 22, 23 which are stacked in the stacking direction (Z direction) of the return flow paths 26 through communication units 14 to 19 and which are arranged between the return flow paths 26. The second fluid paths 22, 23 have U-shaped flow paths in which the second fluid turns back and makes a U turn at an end 13 on the surface substantially perpendicular to Z direction. The communication units 14 to 19 communicating with the U-shaped flow paths are arranged at the other end of the second fluid path unit. Therefore, it is possible to provide a easy to assemble heat exchanger which is able to be produced efficiently.

Abstract: An aluminum alloy extruded product exhibiting excellent surface properties, comprising 0.8 to 1.6% of Mn and 0.4 to 0.8% of Si at a ratio of Mn content to Si content (Mn %/Si %) of 0.7 to 2.4, with the balance being Al and inevitable impurities, the number of intermetallic compounds with a diameter (circle equivalent diameter) of 0.1 to 0.9 ?m dispersed in a matrix being 2×105 or more per square millimeter. The aluminum alloy extruded product allows extrusion of a thin multi-port tube at a high limiting extrusion rate, prevents deposits from adhering to the surface of the extruded tube, and may be suitably used as a constituent member for an aluminum alloy automotive heat exchanger.

Abstract: An evaporator operated with the carbon dioxide gas, comprises at least a unit core including a plurality of heat transmission tubes having a path with a refrigerant flowing therein, a first tank connected to an end opening of the heat transmission tubes and formed with a refrigerant supply path and a second tank connected to the other end opening of the heat transmission tubes and formed with a refrigerant discharge path. The width L1 of the unit core is given as 50 mm?L1?175 mm. The equivalent diameter d of the refrigerant supply path of the first tank and the refrigerant discharge path of the second tank is given as 4.7 mm?d?9.6 mm.

Abstract: There is provides a heat exchanger comprising: a plurality of tubes (110) stacked on each other; and a pair of header tanks (140), each header tank (140) having a flow section (151) in which fluid flows, extending in a direction of stack of the tubes (110), wherein both end sections (111) of the tubes (110) in the longitudinal direction are joined to the pair of header tanks (140), the flow section (151) of each header tank (140) and the inside of each tube (110) are communicated with each other, a tip position (a) of the tube end section (111) is arranged in an outside region of the flow section (151), and an inner wall width size (b) of the flow section (151) is smaller than a size (c) in the width direction of the header tank (140) at the tube end section (111).

Abstract: There is provides a heat exchanger comprising: a plurality of tubes (110) stacked on each other; and a pair of header tanks (140), each header tank (140) having a flow section (151) in which fluid flows, extending in a direction of stack of the tubes (110), wherein both end sections (111) of the tubes (110) in the longitudinal direction are joined to the pair of header tanks (140), the flow section (151) of each header tank (140) and the inside of each tube (110) are communicated with each other, a tip position (a) of the tube end section (111) is arranged in an outside region of the flow section (151), and an inner wall width size (b) of the flow section (151) is smaller than a size (c) in the width direction of the header tank (140) at the tube end section (111).

Abstract: A refrigerant evaporator includes an upstream tank portion for distributing refrigerant into all laminated tubes of a core portion. The upstream tank portion includes a first distribution passage for distributing the refrigerant into the tubes in a direction parallel to a tank longitudinal direction, a second distribution passage for distributing the refrigerant from the first distribution passage into the tubes in a tank width direction, and a communication passage through which the refrigerant from the first distribution passage is supplied to the second distribution passage after flowing in the tank longitudinal direction. Therefore, refrigerant can be uniformly introduced into all the tubes.

Abstract: A refrigerant evaporator includes a tank constituted by a tank portion and a header plate. The tank portion includes refrigerant collecting portions for guiding the refrigerant passed through a first path to the ends of the tank in the right-and-left direction and refrigerant distributing portions for guiding the refrigerant to the tubes forming a second pass. The header plate has refrigerant collecting/distributing space for the tubes. Side tanks are arranged to cover open portions at the ends of the tank in the right-and-left direction, and to spatially connect the flow passages. Separators are provided at portions where the flow passages are to be spatially blocked to constitute a front-and-rear right-and-left cross path. An increased sectional area of flow passages is obtained at the refrigerant flow corner portions relying upon a simple constitution, to decrease the pressure loss on the refrigerant side in the tank and to enhance performance.

Abstract: An evaporator for an air conditioning apparatus has an upper and a lower tanks and multiple tubes vertically extending and respectively connected to the tanks at upper and lower ends. A fluid passage portion is formed in the lower tank. Multiple drainage recesses are formed in the lower tank at such portions, at which the recesses do not interfere with the fluid passage portion.

Abstract: A high-strength aluminum alloy extruded product for heat exchangers which excels in extrudability, allows a thin flat multi-cavity tube to be extruded at a high critical extrusion rate, and excel in intergranular corrosion resistance at a high temperature, and a method of manufacturing the same. The aluminum alloy extruded product includes an aluminum alloy including 0.2 to 1.8% of Mn and 0.1 to 1.2% of Si, having a ratio of Mn content to Si content (Mn %/Si %) of 0.7 to 2.5, and having a content of Cu as an impurity of 0.05% or less, with the balance being Al and impurities, the aluminum alloy extruded product having an electric conductivity of 50% IACS or more and an average particle size of intermetallic compounds precipitating in a matrix of 1 ?m or less.

Abstract: In a tube for a heat exchanger, a plurality of passages is defined. The passages are arranged in rows parallel to a major axis of the tube cross-section and staggered. When the tube is extruded, an extrusion material can flow around dies for forming passages and easily merge between the dies. Since walls between adjacent passages can be easily formed, formability of the tube is improved.

Abstract: In a high-pressure side heat exchanger for a vapor compression refrigerant cycle, a refrigerant passage is formed such that a flow area (S), a length (L), and an equivalent diameter (d) satisfy the conditional expression 0.04×e?1.8d?S/L?2.1×e?1.8d. The flow area (S) is obtained by dividing the product of a total cross-sectional area of the passages in one tube and the number of tubes by the path number. The length (L) is a flow distance of the refrigerant from the refrigerant inlet to the refrigerant outlet. That is, the length (L) is obtained by the product of the length of the tube and the path number. The diameter (d) is obtained by dividing the product of four and the cross-sectional area of the passage by a circumference of the passage.

Abstract: A heat exchanger is used in a vapor-compression type refrigerator where a pressure of a refrigerant at a high-pressure portion reaches and exceeds a critical pressure. A low-pressure refrigerant flows through the heat exchanger. The heat exchanger comprises a flat tube; refrigerant channels included in the tube; and inner pillars disposed between the refrigerant channels. A tensile strength of material of the tube is defined as S [N/mm2]; of one of the refrigerant channels, a dimension approximately parallel with a major-axis direction of the tube, as Wp [mm]; and, of one of the pillars, a thickness approximately parallel with the major-axis direction of the tube, as Ti [mm]. Here, [447×Wp/{10^(1.54×log10S)}?533/{10^(1.98×log10S)}]?Ti?[447×Wp/{10^(1.54×log10S)}?533/{10^(1.98×log10S)}]×2.3.

Abstract: In an internal heat exchanger, when a corresponding diameter of a high pressure passage 5a is ?h, a passage length Lh of the high pressure passage (5a) is so set as to satisfy the relation 9.16/{LN(4.5??h+1.03)}<Lh<46/{LN(4.5??h+1.03)}, and when a corresponding diameter of a low pressure passage 5c is ?l, a passage length Ll of the low pressure passage 5c is so set as to satisfy the relation 9.16/{LN(0.56×6??l+1.02)}<Ll<46/{LN(0.56×6??+1.02)}, a passage sectional area Ah of the high pressure passage 5a is so set as to satisfy the relation 100×(0.25×?h1.2)?1/(0.04×?h+1.7)<Ah <100×(500×?h1.2)?1(0.04×?h+1.7), and a passage sectional area Al of the low pressure passage 5c is so set as to satisfy the relation 1.65/?l0.67<Al<626/?l0.67.

Abstract: A heat exchanger is used in a vapor-compression type refrigerator where a pressure of a refrigerant at a high-pressure portion reaches and exceeds a critical pressure. A low-pressure refrigerant flows through the heat exchanger. The heat exchanger comprises a flat tube; refrigerant channels included in the tube; and inner pillars disposed between the refrigerant channels. A tensile strength of material of the tube is defined as S [N/mm2]; of one of the refrigerant channels, a dimension approximately parallel with a major-axis direction of the tube, as Wp [mm]; and, of one of the pillars, a thickness approximately parallel with the major-axis direction of the tube, as Ti [mm]. Here, [447×Wp/{10{circumflex over ( )}(1.54×log10S)}−533/{10{circumflex over ( )}(1.98×log10S)}]≦Ti≦[447×Wp/{10{circumflex over ( )}(1.54×log10S)}−533/{10{circumflex over ( )}(1.

Abstract: A heat exchange tube having a flat shape includes a plurality of fluid paths having a perfect circular cross section and extending in a longitudinal direction of the tube. Each fluid path is parallel together. The tube has a certain dimensions in such a manner that a distance between two adjacent fluid paths is defined as Wt, and a circumferential thickness between a surface of the tube and an outmost fluid path is defined as Ht. The distance Wt and the circumferential thickness Ht have a relationship as 0.42≦Ht/Wt≦0.98.

Abstract: A heat exchanger includes aligned tubes and upper and lower header tank units, each of which includes two fluid conduits communicated with the tubes. Each header tank unit further includes an intermediate plate, which defines a plurality of communication holes therethrough. Each communication hole communicates between a corresponding one of the tubes and a corresponding one of chambers defined by the fluid conduits of the header tank unit such that each tube is spaced apart from the corresponding one of the chambers.

Abstract: In a heat exchanger, a core has a first core portion including first tubes and a second core portion including second tubes. The first tubes defines first passages through which an internal fluid flows and the second tubes defines second passages through which the internal fluid passed through the first passages flows. A flow direction of the internal fluid passed through a first section of the first core portion and a flow direction of the refrigerant passed through a second section of the first core portion are changed with respect to a direction that the tubes are layered, before flowing in the second core portion. Thus, the internal fluid passed through the first section of the first core portion flows into a second section of the second core portion and the internal fluid passed through the second section of the first core portion flows into a first section of the second core portion.

Abstract: In a vehicle air conditioner with a heat pump refrigerant cycle, an interior heat exchanger of the refrigerant cycle is disposed in an air conditioning case to heat air in a heating operation and to cool air in a cooling operation. Further, a cooling heat exchanger for cooling air by evaporating the refrigerant is disposed so that a part of refrigerant circulating in the refrigerant cycle flows into the cooling heat exchanger at least in the heating operation. In addition, a decompression unit for decompressing refrigerant flowing to the cooling heat exchanger is disposed, and the decompression unit is opened even in the cooling operation. Accordingly, dehumidifying capacity of the air conditioner can be improved while the refrigerant cycle has a simple structure.

Abstract: In a high-pressure side heat exchanger for a vapor compression refrigerant cycle, a refrigerant passage is formed such that a flow area (S), a length (L), and an equivalent diameter (d) satisfy the conditional expression 0.04×e−1.8d≦S/L≦2.1×e−1.8d. The flow area (S) is obtained by dividing the product of a total cross-sectional area of the passages in one tube and the number of tubes by the path number. The length (L) is a flow distance of the refrigerant from the refrigerant inlet to the refrigerant outlet. That is, the length (L) is obtained by the product of the length of the tube and the path number. The diameter (d) is obtained by dividing the product of four and the cross-sectional area of the passage by a circumference of the passage.

Abstract: In a heat exchanging apparatus for a vapor compression refrigerant cycle, an internal heat exchanger is attached to an end of a radiator. The internal heat exchanger is arranged such that high-pressure refrigerant passages are closer to the radiator than low-pressure refrigerant passages. The heat exchanging apparatus can be mounted on a vehicle such that the radiator receives cooling air more than the internal heat exchanger. Because the internal heat exchanger performs heat exchange between high-pressure refrigerant and low-pressure refrigerant, performance of the internal heat exchanger is not degraded even if it is located at a part receiving less cooling air. Thus, the heat exchanging apparatus is easily mounted on a vehicle by integrating the internal heat exchanger with the radiator, without reducing a cooling capacity of the radiator.