JP2008116116A - Tube for heat exchanger and heat exchanger with the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tube for a heat exchanger capable of preventing leakage of liquid, and the heat exchanger with the same. <P>SOLUTION: This tube for the heat exchanger constituted by cylindrically combining a first member 31 and a second member 32, by brazing, has overlapped areas 35, 36 where the first member 31 and the second member 32 are overlapped to each other, a thickness t1 of the overlapped areas 35, 36 of the first member 31 is thinner than a thickness t2 of the other area of the first member 31, and a thickness t3 of the overlapped areas 35, 36 of the second member 32 is thinner than a thickness t4 of the other area of the second member 32. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tube for a heat exchanger that performs heat exchange between fluids and a heat exchanger including the tube.

Patent Document 1 discloses a tube having a structure in which an outer casing and an inner casing are fitted to face each other. The outer casing and the inner casing are formed by pressing a band-shaped metal plate, and each has a substantially rectangular cross section. The outer casing has a side wall portion and two outer edges formed by bending both sides thereof. The inner surface of the outer edge is a brazing material surface in which brazing materials are laminated. The inner casing has a side wall and two inner edges that fit inside the outer edges of the outer casing. The outer surface of the inner edge is a brazing material surface in which brazing materials are laminated. Both ends of the tube produced by fitting the outer casing and the inner casing are inserted into insertion holes respectively provided in the upper tank and the lower tank. Thereafter, a fitting surface of the outer casing and the inner casing, and a root portion where the tube and the tank are connected are formed by brazing.
JP 2004-92940 A

  In the tube disclosed in Patent Document 1, the side surface portion of the tube where the outer edge and the inner edge overlap has a thickness equivalent to two metal plates, and is thicker than other portions. For this reason, since the heat mass (heat capacity) increases at the side surface of the tube, the temperature hardly rises even when heated. As a result, the fluidity of the brazing material is deteriorated, and the brazing property at the root portion where the tube and the tank are connected is lowered. Therefore, the heat exchanger using such a tube has a problem that fluid leakage may occur at the root portion.

  The objective of this invention is providing the tube for heat exchangers which can prevent the leakage of a fluid, and a heat exchanger provided with the same.

  In order to achieve the above object, the present invention employs the following technical means.

  The invention according to claim 1 is a heat exchanger tube in which the first member (31) and the second member (32) are combined in a cylindrical shape and joined to each other by brazing. The member (31) and the second member (32) have overlapping regions (35, 36) in which the members (31) and the second member (32) overlap each other, and the first member 31 in the overlapping region (35, 36). The wall thickness (t1) of the second member (32) is thinner than the second wall thickness (t2) in the other region of the first member (31), and the second member (32) overlaps the region (35, 36). The thickness (t3) of No. 3 is characterized by being thinner than the fourth thickness (t4) in other regions of the second member (32).

  Thereby, since the thickness of the tube for heat exchangers in the overlapping region (35, 36) can be relatively reduced, the heat capacity in the overlapping region (35, 36) can be reduced. For this reason, since the temperature in the overlapping region (35, 36) is likely to rise in the brazing step, the fluidity of the brazing material is increased. Accordingly, brazing at the root portion when connecting the tube to the tank is improved, and fluid leakage can be prevented.

  As in the second aspect of the invention, the first thickness (t1) is substantially half of the second thickness (t2), and the third thickness (t3) is the fourth thickness (t4). ). Further, as in the invention described in claim 3, the first thickness (t1) and the third thickness (t3) can be made substantially the same. Further, as in the invention described in claim 4, the second thickness (t2) and the fourth thickness (t4) can be made substantially the same.

  In the invention according to claim 5, the sum of the first thickness (t1) and the third thickness (t3), and the second thickness (t2) and the fourth thickness (t4) It is characterized by being almost identical. As a result, the wall thickness in the overlap region (35, 36) of the heat exchanger tube becomes equal to the wall thickness in the other region, so that the temperature in the overlap region (35, 36) in the brazing process is different. It becomes easy to rise to the same extent as the temperature in the region.

  As in the sixth aspect of the present invention, the first bottom surface portion (30a) composed of the first member (31) and the second bottom surface portion (30a) are composed of the first bottom surface portion (30a). ) And the two bottom surface portions (30c, 30d) each provided with at least part of the second bottom surface portion (30b) and the overlapping region (35, 36) disposed opposite to each other. Can be included. Further, as in the invention described in claim 7, the overlapping region (35, 36) can be substantially the entire area of each of the two side surface portions (30c, 30d). Further, as in the invention described in claim 8, the overlapping region (65, 66) can be a part of each of the two side surfaces (60c, 60d).

  In the invention according to claim 9, the first member (31) and the second member (32) are overlapped in this order from the inside in both of the two overlapping regions (35, 36). It is a feature. Thereby, since the 1st member (31) can be inserted in the 2nd member (32), it becomes easy to temporarily fix the 1st and 2nd members (31, 32).

  According to the tenth aspect of the present invention, in one of the two overlapping regions (55, 56), the first member (51) and the second member (52) are overlapped in this order from the inside. The other of (55, 56) is characterized in that the second member (52) and the first member (51) are superposed in this order from the inside. The invention according to claim 11 is characterized in that the first and second members (51, 52) have substantially the same shape.

  As a result, the first and second members (51, 52) having the same shape are combined to produce the heat exchanger tube. Therefore, the first and second members (51, 52) are used as common parts. This can reduce the manufacturing cost of the heat exchanger tube.

  As in the invention described in claim 12, these heat exchanger tubes can be used in a heat exchanger.

  Here, the reference numerals in parentheses of the above means indicate the correspondence with specific means described in the embodiments described later.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 to 8. FIG. 1 is a front view showing a configuration of a heater core as a heat exchanger in the present embodiment. FIG. 2 is a cross-sectional view showing a configuration in the vicinity of the root portion of the heat exchanger taken along line II-II in FIG. A white thick arrow in FIG. 1 represents a direction in which a fluid (for example, engine coolant) flows. As shown in FIGS. 1 and 2, the heat exchanger 1 includes a pair of header tanks 10 and 11, a bypass tube (heat exchanger tube) 30 that communicates between the central portions of the header tanks 10 and 11, and a bypass. A plurality of flat tubes 16 are provided in parallel on both sides of the tube 30 and communicated between the header tanks 10 and 11. Between two adjacent flat tubes 16, fins 37 (shown only at the four corners of the heat exchanger 1 in FIG. 1) in which a band-shaped metal plate is formed into a wave shape are arranged. The main part of the heat exchanger 1 has a substantially bilaterally symmetric structure with respect to the bypass tube 30, and heat exchange between the engine coolant and other fluid (for example, air) can be performed independently on the left and right.

  The lower header tank 11 has a U-shaped cap cell 14 and a sheet metal 15 covering the opening of the cap cell 14. The capsule 14 is manufactured using a clad material having a three-layer structure of a brazing material, a core material, and a sacrificial material. The sheet metal 15 is provided with a plurality of insertion holes into which one end portions of the bypass tube 30 and the plurality of flat tubes 16 are respectively inserted. An inlet 17 through which fluid flows is provided at one end (the right end in FIG. 1) of the header tank 11, and another inlet 18 is provided at the other end (the left end in FIG. 1). ing. The internal space of the header tank 11 is divided by a partition plate 19 provided near the inflow port 17 and a partition plate 20 provided near the inflow port 18.

  The upper header tank 10 has a U-shaped cap cell 12 and a sheet metal 13 covering the opening of the cap cell 12. The capsule 12 is manufactured using a clad material having a three-layer structure similar to the capsule 14. The sheet metal 13 is provided with a plurality of insertion holes into which the other ends of the bypass tube 30 and the plurality of flat tubes 16 are respectively inserted. In addition, an outlet (not shown) through which fluid flows out is opened at the center of the capsule 12, and an outlet pipe 21 is connected to the outlet. The internal space of the header tank 10 is divided by partition plates 22 and 23 provided close to both sides with the bypass tube 30 and the outflow pipe 21 interposed therebetween.

  Here, the flat tube 16 includes a plurality of flat tubes 16 a connected between the inlet 17 and the partition plate 19 in the header tank 11, and between the partition plate 19 and the bypass tube 30 in the header tank 11. A plurality of flat tubes 16b connected to each other, a plurality of flat tubes 16c connected between the bypass tube 30 and the partition plate 20 in the header tank 11, and a partition plate 20 and an inflow port in the header tank 11. 18 and a plurality of flat tubes 16d connected to each other.

  The engine coolant that has flowed into the header tank 11 from the inflow port 17 at a predetermined flow rate flows to the header tank 10 side through the flat tube 16a. The engine coolant flowing into the header tank 10 returns to the header tank 11 through the flat tube 16b. The engine coolant flowing through the flat tubes 16a and 16b exchanges heat with air flowing through an air passage (not shown). As a result, the air is heated to a predetermined temperature according to the flow rate of the engine cooling water, and is blown into the passenger compartment, for example, from the outlet on the driver's seat side. The engine coolant that has returned to the header tank 11 flows again to the header tank 10 side through the bypass tube 30 and flows out to the engine side through the outflow pipe 21.

  On the other hand, the engine coolant that has flowed into the header tank 11 from the inlet 18 at a predetermined flow rate adjusted independently of the flow rate of the engine coolant flows to the header tank 10 side through the flat tube 16d. The engine coolant flowing into the header tank 10 returns to the header tank 11 through the flat tube 16c. The engine coolant flowing through the flat tubes 16c and 16d exchanges heat with air flowing through an air passage different from the above air passage. As a result, the air is heated to a predetermined temperature according to the flow rate of the engine cooling water, and is blown into the passenger compartment, for example, from the outlet on the passenger seat side. The engine coolant that has returned to the header tank 11 flows again to the header tank 10 side through the bypass tube 30 and flows out to the engine side through the outflow pipe 21.

  3 is an external view showing a configuration of the bypass tube 30 as viewed from the right side in FIG. 4 is a cross-sectional view showing the configuration of the bypass tube 30 cut along the line IV-IV in FIG. As shown in FIGS. 3 and 4, the bypass tube 30 has a structure in which, for example, a first member 31 and a second member 32 each having a U-shaped cross-sectional shape are combined in a square tube shape. Yes. The first and second members 31 and 32 are both made of a clad material having the same three-layer structure as the capsules 12 and 14. The first member 31 and the second member 32 are overlapped with each other in the two overlapping regions 35 and 36, and are joined to each other by brazing (brazing). The width w1 of the bypass tube 30 is 27 mm, for example, and the height h1 is 8 mm, for example. The bypass tube 30 has a fluid passage 33 having a rectangular cross section defined by the first and second members 31 and 32.

  The first U-shaped first member 31 has a bottom surface 31a and two side surfaces 31b and 31c substantially perpendicular to the bottom surface 31a. A corner portion 31d is formed at the boundary between the bottom surface 31a and the side surface 31b, and a corner portion 31e is formed at the boundary between the bottom surface 31a and the side surface 31c. The wall thickness t2 in almost the entire area of the bottom surface 31a is substantially the same as the wall thickness of the capsules 12 and 14, for example, 0.8 mm. The thickness t1 of the side surface 31b is smaller than the thickness t2 of the bottom surface 31a (t2> t1), for example, approximately half (0.4 mm) of the thickness t2. The thickness of the side surface 31c is substantially the same as the thickness t1 of the side surface 31b. The thickness of the bottom surface 31a in the vicinity of both corners 31d and 31e is substantially the same as the thickness t1 of the side surfaces 31b and 31c.

  The second member 32 having a U-shaped cross section has a bottom surface 32a and two side surfaces 32b and 32c substantially perpendicular to the bottom surface 32a. A corner portion 32d is formed at the boundary between the bottom surface 32a and the side surface 32b, and a corner portion 32e is formed at the boundary between the bottom surface 32a and the side surface 32c. The thickness t4 in almost the entire area of the bottom surface 32a is substantially the same as the thickness t2 of the bottom surface 31a and the thickness of the capsules 12 and 14, for example, 0.8 mm. The thickness t3 of the side surface 32b is smaller than the thickness t4 of the bottom surface 32a (t4> t3), for example, approximately half (0.4 mm) of the thickness t4. The thickness of the side surface 32c is substantially the same as the thickness t3 of the side surface 32b. The thickness of the bottom surface 32a in the vicinity of both corners 32d and 32e is substantially the same as the thickness t3 of the side surfaces 32b and 32c.

  The width of the bottom surface 32 b of the second member 32 is equal to the width w1 of the bypass tube 30. On the other hand, the width of the bottom surface 31a of the first member 31 is narrower than the width of the bottom surface 32a of the second member 32 by the sum of the thicknesses (2 × t3) of the side surfaces 32b and 32c of the second member 32. ing. As a result, the first member 31 is fitted into the second member 32 so that the outside of the side surfaces 31b and 31c and the inside of the side surfaces 32b and 32c are in contact with each other.

  The bypass tube 30 in which the first and second members 31 and 32 are combined has a rectangular cross-sectional shape as a whole, and includes a planar bottom surface portion 30a constituted by the bottom surface 31a of the first member 31 and And a bottom surface portion 30b having a planar shape which is disposed to face the bottom surface portion 30a and is configured by the bottom surface 32a of the second member 32. The thickness of the bottom surface portion 30a is t2, and the thickness of the bottom surface portion 30b is t4 (= t2). Further, the bypass tube 30 is disposed to face the side surface portion 30c and a planar side surface portion 30c connected to one side end portion (right side end portion in FIG. 4) of the bottom surface portions 30a and 30b, Each of the bottom surface portions 30a and 30b has a planar side surface portion 30d connected to the other side end portion (left side end portion in FIG. 4). The side surface portion 30c includes the overlapping region 35 over substantially the entire area, and the side surface portion 30d includes the overlapping region 36 over the entire area.

  In the overlapping region 35, the side surface 31b of the first member 31 and the side surface 32b of the second member 32 are overlapped in this order from the fluid passage 33 side (inner side). In the overlapping region 36, the side surface 31c of the first member 31 and the side surface 32c of the second member 32 are overlapped in this order from the fluid passage 33 side. The thickness t1 of the side surfaces 31b and 31c of the first member 31 is half the thickness t2 of the bottom surface 31a, and the thickness t3 of the side surfaces 32b and 32c of the second member 32 is the thickness t4 (= t2) of the bottom surface 32a. ), The thickness t5 (= t1 + t3) of the side surface portions 30c and 30d of the bypass tube 30 is substantially the same as the thickness t2 of the bottom surface portion 30a and the thickness t4 of the bottom surface portion 30b (t5 = t2 = t4).

  Next, the manufacturing method of the heat exchanger tube and the heat exchanger in the present embodiment will be described. FIG. 5 is a process cross-sectional view illustrating a part of the manufacturing process of the first member 31 constituting the bypass tube 30. First, as shown in FIG. 5A, a band-shaped metal plate 40 extending in a direction perpendicular to the paper surface is formed. The metal plate 40 is formed of a clad material having a three-layer structure, which is the same material as the formation material of the capsules 12 and 14.

  FIG. 6 is a schematic cross-sectional view showing a laminated structure of the metal plate 40. The upper side of FIG. 6 is the tube inner surface side (engine coolant side) that becomes the inner surface side after the bypass tube 30 is manufactured, and the lower side is the tube outer surface side (air side) that becomes the outer surface side. As shown in FIG. 6, the metal plate 40 is laminated on a core material layer 40a, a brazing filler metal layer 40b laminated on the tube outer surface side of the core material layer 40a, and a tube inner surface side of the core material layer 40a. And a sacrificial material layer 40c for preventing corrosion. The core material layer 40a, the brazing material layer 40b, and the sacrificial material layer 40c are all formed of an aluminum alloy, for example. The plate thickness t0 of the metal plate 40 is, for example, about 0.8 mm.

  Next, as shown in FIG.5 (b), the side edge part of the both sides of the metal plate 40 is rolled, and the thin parts 40d and 40e with thin thickness are formed. The thickness t6 of the thin portions 40d and 40e is, for example, about half (0.4 mm) of the plate thickness t0. Further, the width w3 of the thin portions 40d and 40e is, for example, about 10 mm, and the width w2 of the entire metal plate 40 on which the thin portions 40d and 40e are formed is, for example, about 43 mm. Here, the core material layer 40a, the brazing material layer 40b, and the sacrificial material layer 40c of the metal plate 40 extend substantially uniformly by rolling. Therefore, the three-layer structure of the core material layer 40a, the brazing material layer 40b, and the sacrificial material layer 40c in the thin portions 40d and 40e is maintained, and the cladding ratio of each layer in the thin portions 40d and 40e is the other part of the metal plate 40. It is almost equal to the cladding ratio of each layer.

  A first member 31 having a U-shaped cross section is produced by bending the metal plate 40 substantially vertically upward in the drawing at a part of each of the thin-walled portions 40d and 40e (portions that become corner portions 31d and 31e). The

  On the other hand, the second member 32 is manufactured through a process similar to that of the first member 31 using a clad material having a three-layer structure which is the same material as that for forming the capsules 12 and 14 and the metal plate 40. However, the width of the thin portion formed at the side end portions on both sides of the metal plate is formed to be approximately twice as large as the thickness t6 than the width w3 of the thin portions 40d and 40e shown in FIG. The As a result, the second member 32 can fit the first member 31 inside.

  The produced first and second members 31 and 32 are combined to produce a bypass tube (assembly) 30 as shown in FIGS. Thereafter, the bypass tube 30 and the flat tube 16 produced through another process are inserted into insertion holes provided in the header tanks 10 and 11, and the other components of the heat exchanger 1 are assembled and heated. The material layer is melted and the components are brazed together. The heat exchanger 1 shown in FIG. 1 is produced through the above steps.

  FIG. 7 is an enlarged view showing a main part of the root portion of the manufactured heat exchanger 1. In FIG. 7, the area A of FIG. 2 is shown enlarged. As shown in FIG. 7, in the root portion where the bypass tube 30 is inserted into the insertion hole of the sheet metal 15, the insertion hole end side 15 a of the sheet metal 15 and the curved surface outside the corner portion 31 d of the first member 31. A gap 34 is formed in a region surrounded by the surface of the end 32 f of the second member 32. However, in the present embodiment, the thickness t5 of the side surface portion 30c of the bypass tube 30 is relatively thin, for example, equal to the thickness t2 of the bottom surface portion 30a. Therefore, an increase in the heat capacity at the side surface portion 30c can be suppressed. Thereby, in the brazing process, the temperature of the side surface portion 30c is likely to rise to the same extent as the bottom surface portion 30a, and the brazing material is sufficiently melted, so that the fluidity of the brazing material in the vicinity of the side surface portion 30c is increased. For this reason, the gap | interval part 34 is block | closed more reliably by the brazing material which flows favorably from another part. Moreover, in this embodiment, since the corner | angular part 31d is formed in the thin part area | region among the 1st members 31, the curvature radius of the curved surface outside the corner | angular part 31d can be made small. For this reason, since the area of the gap | interval part 34 becomes comparatively small, the gap | interval part 34 is block | closed with a small amount of brazing materials. Therefore, according to this embodiment, since the brazing property at the root portion is improved, it is possible to realize a heat exchanger tube capable of preventing fluid leakage and a heat exchanger including the tube.

  In addition, since both side surfaces 31b and 31c of the first member 31 are fitted inside the both side surfaces 32b and 32c of the second member 32, the first member 31 or the second member 32 itself has elasticity due to the elasticity of the first member 31 or the second member 32 itself. The first member 31 and the second member 32 can be temporarily fixed to each other. For this reason, when the 1st member 31 and the 2nd member 32 are assembled | attached, the process for temporarily fixing the 1st and 2nd members 31 and 32 is simplified. Therefore, the heat exchanger tube and the heat exchanger can be manufactured with fewer man-hours.

  FIG. 8 is a cross-sectional view showing a modification of the configuration of the bypass tube in the present embodiment. As shown in FIG. 8, in the bypass tube 50 of the present modification, the first member 51 and the second member 52 have the same shape (same dimensions) as compared to the bypass tube 30 shown in FIGS. And is characterized by being alternately combined. The first and second members 51 and 52 are both made of a clad material having the same three-layer structure as the capsules 12 and 14. The first member 51 and the second member 52 are overlapped with each other in the two overlapping regions 55 and 56, and are joined to each other by brazing. The bypass tube 30 has a fluid passage 53 having a rectangular cross section defined by the first and second members 51 and 52.

  The first member 51 having a U-shaped cross section has a bottom surface 51a and two side surfaces 51b and 51c substantially perpendicular to the bottom surface 51a. The thickness of almost the entire bottom surface 51a is the same as the thickness of the capsules 12 and 14, for example, 0.8 mm. The thickness of the side surfaces 51b and 51c is, for example, half (0.4 mm) the thickness of the bottom surface 51a.

  The second member 52 having a U-shaped cross section has a bottom surface 52a and two side surfaces 52b and 52c substantially perpendicular to the bottom surface 52a. The thickness of almost the entire bottom surface 52a is the same as the thickness of the bottom surface 51a and the thickness of the capsules 12 and 14, for example, 0.8 mm. The thickness of the side surfaces 52b and 52c is, for example, half (0.4 mm) the thickness of the bottom surface 52a. The second member 52 has substantially the same shape as the first member 51 and is, for example, a component common to the first member 51.

  The bypass tube 50 in which the first and second members 51 and 52 are combined is arranged so as to be opposed to the bottom surface portion 50a constituted by the bottom surface 51a of the first member 51 and the bottom surface portion 50a. And a bottom surface portion 50b composed of a bottom surface 52a. The thickness of the bottom surface portion 50a and the thickness of the bottom surface portion 50b are the same. Further, the bypass tube 50 includes a side surface portion 50c that includes the overlapping region 55 in substantially the entire region, and a side surface portion 50d that is disposed to face the side surface portion 50c and includes the overlapping region 56 in approximately the entire region. In the overlapping region 55, the side surface 51b of the first member 51 and the side surface 52b of the second member 52 are overlapped in this order from the fluid passage 53 side. On the other hand, in the overlapping region 56, the side surface 52c of the second member 52 and the side surface 51c of the first member 51 are overlapped in this order from the fluid passage 53 side. The thickness of the side surface portions 50c and 50d of the bypass tube 50 is substantially the same as the thickness of the bottom surface portion 50a and the thickness of the bottom surface portion 50b.

  According to this modified example, the brazing performance at the root portion is improved similarly to the bypass tube shown in FIGS. 3 and 4, so that the effect of preventing fluid leakage can be obtained. Furthermore, in this modification, since the first member 51 and the second member 52 have the same shape, the manufacturing cost of the bypass tube can be further reduced by sharing parts.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a cross-sectional view showing the configuration of the bypass tube in the present embodiment. As shown in FIG. 9, the bypass tube 60 has a structure in which, for example, a first member 61 and a second member 62 each having a U-shaped cross-sectional shape are combined in a square tube shape. The first and second members 61 and 62 are both made of a clad material having the same three-layer structure as the capsules 12 and 14. The first member 61 and the second member 62 are overlapped with each other in the two overlapping regions 65 and 66, and are joined to each other by brazing. The width of the bypass tube 60 in the left-right direction in the figure is 27 mm, for example, and the height in the vertical direction in the figure is 8 mm, for example. The bypass tube 60 has a fluid passage 63 having a rectangular cross section defined by the first and second members 61 and 62.

  The first member 61 having a U-shaped cross section has a bottom surface 61a and two side surfaces 61b and 61c substantially perpendicular to the bottom surface 61a. The thickness t8 of the bottom surface 61a is substantially the same as the thickness of the capsules 12 and 14, and is, for example, 0.8 mm. The side surface 61b has a tip portion 61d having a shape in which the outer surface near the tip is cut out. The thickness t7 at the tip 61d of the side surface 61b is substantially half (0.4 mm) of the thickness t8 of the bottom surface 61a. The thickness of the portion of the side surface 61b excluding the tip portion 61d is substantially the same as the thickness t8 of the bottom surface 61a. The side surface 61c has a tip portion 61e having a shape in which the inner surface near the tip is cut out. The thickness at the front end 61e of the side surface 61c is substantially the same as the thickness t7 at the front end 61d of the side surface 61b. The thickness of the side surface 61c excluding the front end portion 61e is substantially the same as the thickness t8 of the bottom surface 61a. The tip portions 61d and 61e each have a length of about 2 to 3 mm and are formed by, for example, coining.

  The second member 62 having a U-shaped cross section has a bottom surface 62a and two side surfaces 62b and 62c substantially perpendicular to the bottom surface 62a. The thickness t10 of the bottom surface 62a is substantially the same as the thickness t8 of the bottom surface 61a and the thickness of the capsules 12 and 14, for example, 0.8 mm. The side surface 62b has a tip portion 62d having a shape in which the inner surface near the tip is cut out. The distal end portion 62d is formed in a complementary manner with respect to the distal end portion 61d of the first member 61 disposed to face the distal end portion 62d. The wall thickness t9 at the tip 62d of the side surface 62b is substantially half (0.4 mm) of the wall thickness t10 of the bottom surface 62a. The thickness of the side surface 62b excluding the front end 62d is substantially the same as the thickness t10 of the bottom surface 62a. Further, the side surface 62c has a tip portion 62e having a shape in which the outer surface near the tip is cut out. The distal end portion 62e is formed in a complementary manner with respect to the distal end portion 61e of the first member 61 disposed to face the distal end portion 62e. The wall thickness at the front end portion 62e of the side surface 62c is substantially the same as the wall thickness t9 of the front end portion 62d of the side surface 62b. The thickness of the side surface 62c excluding the tip 62e is substantially the same as the thickness t10 of the bottom surface 62a. The tip portions 62d and 62e are formed by coining, for example. The second member 62 has substantially the same shape (same dimension) as the first member 61 and is, for example, a component common to the first member 61.

  The bypass tube 60 in which the first and second members 61 and 62 are combined has a rectangular cross-sectional shape as a whole, and includes a bottom surface portion 60a composed of a bottom surface 61a of the first member 61, and a bottom surface portion. It has a bottom surface portion 60b that is disposed to face the surface 60a and is configured by the bottom surface 62a of the second member 62. The thickness of the bottom surface portion 60a is t8, and the thickness of the bottom surface portion 60b is t10 (= t8). In addition, the bypass tube 60 includes a side surface portion 60c that partially includes the overlapping region 65, and a side surface portion 60d that is disposed to face the side surface portion 60c and includes the overlapping region 66. In the overlapping region 65, the distal end portion 61d of the first member 61 and the distal end portion 62d of the second member 62 are overlapped in this order from the fluid passage 63 side. In the overlapping region 66, the distal end portion 62e of the second member 62 and the distal end portion 61e of the first member 61 are overlapped in this order from the fluid passage 63 side. The thickness t11 (= t7 + t9) of the bypass tube 60 in the overlapping regions 66 and 67 is substantially equal to the thickness t8 of the bottom surface portion 60a and the thickness t10 of the bottom surface portion 60b. That is, the wall thickness of the bypass tube 60 is substantially the same over the entire circumference.

  Next, the manufacturing method of the tube for heat exchangers in this embodiment is demonstrated. FIG. 10 is a process cross-sectional view illustrating a part of the manufacturing process of the first member 61 constituting the bypass tube 60. First, as shown in FIG. 10A, a band-shaped metal plate 40 extending in a direction perpendicular to the paper surface is formed. The metal plate 40 is made of the same material as that for forming the capsules 12 and 14, and is formed of a clad material having a three-layer structure as shown in FIG. The plate thickness t0 of the metal plate 40 is, for example, about 0.8 mm.

  Next, as shown in FIG. 10 (b), the side end portions on both sides of the metal plate 40 are coined, and a tip portion 40f having a shape in which the lower surface in the figure is cut out, and the upper surface in the figure And a tip 40g having a shape in which is cut out. The thickness t12 of the distal end portion 40f and the thickness t13 of the distal end portion 40g are, for example, about half (0.4 mm) of the plate thickness t0. The widths w4 of the tip portions 40f and 40g are, for example, about 2 to 3 mm. Here, even if coining is performed, the three-layer structure of the core material layer 40a, the brazing material layer 40b, and the sacrificial material layer 40c at the tip portions 40f and 40g is maintained, and the cladding of each layer near the tip portions 40f and 40g is maintained. The rate is substantially equal to the cladding rate of each layer at other parts of the metal plate 40.

  A first member 61 having a U-shaped cross section is produced by bending the metal plate 40 substantially vertically upward at two locations on both sides.

  The second member 62 is manufactured through a process similar to that of the first member 61 using a clad material having a three-layer structure which is the same material as the forming material of the capsules 12 and 14 and the metal plate 40.

  The bypass tube 60 shown in FIG. 9 is manufactured by combining and brazing the manufactured first member 61 and the second member 62 so that the tip portions of the first member 61 and the second member 62 are joined together without a gap.

  In the present embodiment, the wall thickness t11 in the overlapping regions 65 and 66 of the bypass tube 60 is substantially equal to the wall thickness t8 of the bottom surface portion 60a and the wall thickness t10 of the bottom surface portion 60b. The increase in heat capacity is suppressed. Thereby, in the brazing process, the temperature at the side surface portions 60c and 60d is likely to rise, and the brazing material is sufficiently melted, so that the fluidity of the brazing material is increased. Therefore, according to this embodiment, since the brazing property at the root portion is improved, it is possible to realize a heat exchanger tube capable of preventing fluid leakage and a heat exchanger including the tube.

  In the present embodiment, the tip end portion 61d of the first member 61 and the tip end portion 62d of the second member 62, which are formed complementarily with each other, are joined together without any gap. For this reason, since the gap | interval part 34 as shown in FIG. 7 is not formed, the leak of the fluid in a root part can be prevented more reliably.

  Furthermore, in this embodiment, since the 1st member 61 and the 2nd member 62 can be made into a common component, the manufacturing cost of the tube for heat exchangers can be reduced by reducing the kind of component.

  FIG. 11 is a cross-sectional view showing a modification of the configuration of the bypass tube in the present embodiment. As shown in FIG. 11, the bypass tube 70 of the present modified example has both tip portions 71 d and 71 e of the first member 71 as compared with the bypass tube shown in FIG. 9. , 72e is characterized by being fitted inside. The first and second members 71 and 72 are each made of a clad material having the same three-layer structure as the capsules 12 and 14. The first member 71 and the second member 72 are overlapped with each other in the two overlapping regions 75 and 76, and are joined to each other by brazing. The bypass tube 70 has a fluid passage 73 having a rectangular cross section defined by the first and second members 71 and 72.

  The first member 71 having a U-shaped cross section has a bottom surface 71a and two side surfaces 71b and 71c substantially perpendicular to the bottom surface 71a. The thickness of the bottom surface 71a is the same as the thickness of the capsules 12 and 14, for example, 0.8 mm. The side surface 71b has a tip portion 71d having a shape in which the outer surface near the tip is cut out. The side surface 71c has a tip portion 71e having a shape in which the outer surface near the tip is cut out. The thickness at the distal end portion 71d of the side surface 71b and the thickness at the distal end portion 71e of the side surface 71c are substantially half of the thickness of the bottom surface 71a. The thickness of the side surface 71b excluding the tip end portion 71d and the thickness of the side surface 71c excluding the tip end portion 71e are substantially the same as the thickness of the bottom surface 71a. The tip portions 71d and 71e are formed by coining, for example.

  The second member 72 having a U-shaped cross section has a bottom surface 72a and two side surfaces 72b and 72c substantially perpendicular to the bottom surface 72a. The thickness of the bottom surface 72a in almost the entire region is the same as the thickness of the bottom surface 71a and the thickness of the capsules 12 and 14, for example, 0.8 mm. The side surface 72b has a tip portion 72d having a shape in which the inner surface near the tip is cut out. The distal end portion 72d is formed in a complementary manner with respect to the distal end portion 71d of the first member 71 arranged to face. Further, the side surface 72c has a tip portion 72e having a shape in which the inner surface near the tip is cut out. The distal end portion 72e is formed in a complementary manner with respect to the distal end portion 71e of the first member 71 arranged to face. The wall thickness at the distal end portion 72d of the side surface 72b and the wall thickness at the distal end portion 72e of the side surface 72c are substantially half of the wall thickness of the bottom surface 72a. The thickness of the side surface 72b excluding the front end portion 72d and the thickness of the side surface 72c excluding the front end portion 72e are substantially the same as the thickness of the bottom surface 72a. The distal end portions 72d and 72e are joined to the distal end portions 71d and 71e of the first member 71 without any gaps. The tip portions 72d and 72e are formed by, for example, coining.

  The bypass tube 70 in which the first and second members 71 and 72 are combined is arranged so as to be opposed to the bottom surface portion 70a constituted by the bottom surface 71a of the first member 71 and the bottom surface portion 70a. And a bottom surface portion 70b composed of a bottom surface 72a of 72. The thickness of the bottom surface portion 70a and the thickness of the bottom surface portion 70b are the same. In addition, the bypass tube 70 includes a side surface portion 70c that partially includes the overlapping region 75 and a side surface portion 70d that is disposed to face the side surface portion 70c and includes the overlapping region 76 in part. In the overlapping region 75, the distal end portion 71d of the first member 71 and the distal end portion 72d of the second member 72 are overlapped in this order from the fluid passage 73 side. In the overlapping region 76, the distal end portion 71e of the first member 71 and the distal end portion 72e of the second member 72 are overlapped in this order from the fluid passage 73 side. The thickness of the bypass tube 70 in the overlapping regions 76 and 77 is substantially equal to the thickness of the bottom surface portions 70a and 70b. That is, the wall thickness of the bypass tube 70 is substantially the same over the entire circumference.

  According to this modification, as with the bypass tube shown in FIG. 9, the brazing property at the root portion is improved, so that a heat exchanger tube capable of preventing fluid leakage and a heat exchanger including the same are realized. it can.

  Furthermore, according to this modification, since both the front end portions 71d and 71e of the first member 71 are fitted inside the both front end portions 72d and 72e of the second member 72, the first member 71 or the second member 71 The first member 71 and the second member 72 can be temporarily fixed to each other by the elasticity of the member 72 itself. Therefore, since the process for temporarily fixing the first and second members 71 and 72 is simplified, the heat exchanger tube and the heat exchanger can be manufactured with fewer man-hours.

(Other embodiments)
In the above embodiment, a bypass tube having a rectangular cross-sectional shape is taken as an example, but for example, bypasses having various cross-sectional shapes such as an oblong cross-sectional bypass tube in which two semi-oval members are combined. Applicable to tubes.

  Moreover, in the said embodiment, although the bypass tube was mentioned as an example as a tube for heat exchangers, it is applicable also to another tube.

It is a front view which shows the structure of the heat exchanger in 1st Embodiment of this invention. It is sectional drawing which shows the structure of the heat exchanger cut | disconnected by the II-II line | wire of FIG. It is an external view which shows the structure of the bypass tube in 1st Embodiment of this invention. It is sectional drawing which shows the structure of the bypass tube cut | disconnected by the IV-IV line of FIG. It is process sectional drawing which shows the manufacturing process of the 1st member which comprises the bypass tube in 1st Embodiment of this invention. It is typical sectional drawing which shows the laminated structure of a metal plate. It is an enlarged view which shows the principal part of the root part of a heat exchanger. It is sectional drawing which shows the modification of the structure of the bypass tube in 1st Embodiment of this invention. It is sectional drawing which shows the structure of the bypass tube in 2nd Embodiment of this invention. It is process sectional drawing which shows the manufacturing process of the 1st member which comprises the bypass tube in 2nd Embodiment of this invention. It is sectional drawing which shows the modification of the structure of the bypass tube in 2nd Embodiment of this invention.

Explanation of symbols

30, 50, 60, 70 Bypass tube 30a, 50a, 60a, 70a Bottom surface portion (first bottom surface portion)
30b, 50b, 60b, 70b Bottom part (second bottom part)
30c, 30d, 50c, 50d, 60c, 60d, 70c, 70d Side surface portion 31, 51, 61, 71 First member 32, 52, 62, 72 Second member 35, 36, 55, 56, 65, 66 75, 76 Overlapping area

Claims (12)

A heat exchanger tube in which a first member (31) and a second member (32) are combined in a cylindrical shape and joined together by brazing,
The first member (31) and the second member (32) have overlapping regions (35, 36) where they overlap each other;
The first thickness (t1) in the overlapping region (35, 36) of the first member (31) is the second thickness (t2) in the other region of the first member (31). The third thickness (t3) in the overlapping region (35, 36) of the second member (32) is smaller than the fourth thickness in the other region of the second member (32). A heat exchanger tube, characterized by being thinner than the wall thickness (t4).   The first thickness (t1) is approximately half of the second thickness (t2), and the third thickness (t3) is approximately half of the fourth thickness (t4). The heat exchanger tube according to claim 1.   The heat exchanger tube according to claim 1 or 2, wherein the first thickness (t1) and the third thickness (t3) are substantially the same.   The heat exchanger tube according to any one of claims 1 to 3, wherein the second thickness (t2) and the fourth thickness (t4) are substantially the same.   The sum of the first thickness (t1) and the third thickness (t3), and the second thickness (t2) and the fourth thickness (t4) are substantially the same. The heat exchanger tube according to claim 4. A first bottom surface portion (30a) composed of the first member (31);
A second bottom surface portion (30b) composed of the second member (32) and disposed opposite to the first bottom surface portion (30a);
The superposition region (35, 36) is provided at least in part, and has two side portions (30c, 30d) arranged to face each other. The heat exchanger tube as described in the paragraph.   The tube for a heat exchanger according to claim 6, wherein the overlapping region (35, 36) is substantially the entire area of each of the two side surface portions (30c, 30d).   The tube for a heat exchanger according to claim 6, wherein the overlapping region (65, 66) is a part of each of the two side surfaces (60c, 60d).   The first member (31) and the second member (32) are overlapped in this order from the inside in both of the two overlapping regions (35, 36). The tube for heat exchangers of any one of thru | or 8. In one of the two overlapping regions (55, 56), the first member (51) and the second member (52) are overlapped in this order from the inside,
The second member (52) and the first member (51) are overlapped in this order from the inside in the other of the overlapping regions (55, 56). The tube for heat exchangers of any one of these.   11. The heat exchanger tube according to claim 10, wherein the first and second members (51, 52) have substantially the same shape.   The heat exchanger tube of any one of Claims 1 thru | or 11 is used, The heat exchanger characterized by the above-mentioned.

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