Abstract: A heat exchanger includes a communication flow path 31 which communicates a first lower tank provided in a plurality of laminated flat tubes with a second lower tank provided adjacent to the first lower tank, the communication flow path 31 includes a throttle portion 34 formed in the center in a width direction, the throttle portion 34 has a curved surface formed in a protruded shape inside the communication flow path 31 with a predetermined radius of curvature R, when the length, in which an outer dimension in a height direction is the maximum, of the communication flow path 31 is set to be H, and the length, in which an outer dimension in the width direction is the maximum, of the communication flow path 31 is set to be W, the radius of curvature R of the throttle portion 34 is R?0.2 H.

Abstract: The heating-medium heating unit is provided with a plurality of flat heat-exchange tubes (17) each having an inlet header (22) and an outlet header (23) at one end or both ends of flat tube portions (20) through which a heating medium is circulated; sealing materials (26) that seal the peripheries of communicating holes (24, 25) of the inlet headers (22) and the outlet headers (23) of the stacked flat heat-exchange tubes (17); PTC heaters assembled between the flat tube portions (20) of the flat heat-exchange tubes (17); and a heat-exchange pressing member (16) that presses the alternately stacked flat heat-exchange tubes (17) and PTC heaters into close contact with each other, wherein a deformation-preventing reinforcing portion (29) is provided around each of the communicating holes (24, 25) in the inlet header (22) and the outlet header (23) of each of the flat heat-exchange tubes (17).

Abstract: Provided is a heat exchanger whose air pressure loss is small and whose exchanged heat is large. The heat exchanger includes flat tubes, each having therein a plurality of refrigerant circulation holes, and fins fixed to the flat surfaces of the flat tubes, wherein the flat tubes and the fins are alternately stacked to form the heat exchanger.

Abstract: There is provided a heat exchanger 10 in which each of header tanks 20A and 20B is configured so that each of intermediate plates 60 and 90 is held between a header plate 40 and a tank plate 50. The intermediate plate 60, 90 functions as a reinforcing member, so that the strength of the header tank 20A, 20B is improved. The intermediate plate 60, 90 serving as a reinforcing element comprises bent parts 100 between the central portion and both the end portions in the width direction of the header tank 20A, 20B. By the elastic deformation of the bent parts 100, for example, the stresses developed in brazing of the header tank 20A, 20B, and the stresses at the time when a refrigerant pressure is applied can be prevented from concentrating in the joint portion of the header plate 40, the tank plate 50, and the intermediate plate 60, 90.

Abstract: A heat exchanger 10 includes a first block and a second block. The first block includes a first tank T1 having a refrigerant inlet through which the refrigerant flows in, a plurality of first tubes 21 into which the refrigerant having flowed into the first tank T1 is distributed and flows therein, and a second tank T2 in which the refrigerant flowing in the first tubes 21 merges. The second block includes a third tank T3 into which the refrigerant having merged in the second tank T2 flows therein, a plurality of second tubes 22 into which the refrigerant having flowed into the third tank T3 is distributed and flows, and a fourth tank T4 in which the refrigerant flowing in the second tube merges, and having a refrigerant outlet through which the merged refrigerant flows out. A refrigerant passage 43h through which the refrigerant flows from the second tank T2 into the third tank T3 is locally placed on the opposite side of the refrigerant inlet.

Abstract: A refrigerant evaporator (1), in which one of a plurality of blocks is a U-turn block portion (15), includes a plurality of refrigerant-distribution holes (4M, 5M), which communicate between first tank portions (6, 8) and second tank portions (7, 9), provided in the U-turn block portion (15) and in partition walls (4C, 5C) therein that partition the first tank portions (6, 8) and the second tank portions (7, 9) of top and bottom tanks (4, 5). For the refrigerant-distribution holes (4M, 5M), assuming the distance between the plurality of holes as b, the hole length in the hole-row direction as a, and the thickness of the partition wall as t, a/b is set to a/b??0.0697×t2+0.3274×t+0.4594, where t=1 to 2 mm.

Abstract: At the refrigerant inlet/outlet side surface portion of laminated flat tubes, there is provided a first side refrigerant passage, and in the upper portion of the other side surface portion, there is provided a second side refrigerant passage, and in the lower portion thereof a third side refrigerant passage. A first partition portion is provided in first lower tank portions of the laminated flat tubes, and a second partition portion is provided in second upper tank portions. The first partition portion and the second partition portion respectively divide the laminated first lower tank portions and the second upper tank portions such that the ratio of the number of flat tubes on the refrigerant inlet/outlet side surface portion side, n4, to the number of flat tubes on the opposite side surface portion side, n3, is approximately 2:1.

Abstract: At the refrigerant inlet/outlet side surface portion of laminated flat tubes, there is provided a first side refrigerant passage, and in the upper portion of the other side surface portion, there is provided a second side refrigerant passage, and in the lower portion thereof a third side refrigerant passage. A first partition portion is provided in first lower tank portions of the laminated flat tubes, and a second partition portion is provided in second upper tank portions. The first partition portion and the second partition portion respectively divide the laminated first lower tank portions and the second upper tank portions such that the ratio of the number of flat tubes on the refrigerant inlet/outlet side surface portion side, n4, to the number of flat tubes on the opposite side surface portion side, n3, is approximately 2:1.