WO2017013918A1 - Heat exchanger - Google Patents

Abstract

Provided is a heat exchanger configured so that, even if the thickness of a core plate in the direction of the width of a tube is reduced, the formation of an undesired recess in the core plate is prevented. The core plate (21) of each of the header tanks (20, 30) of a heat exchanger (1) has: a tube joint section (211) in which a plurality of tube insertion holes (211a) are formed; receiving and housing sections (212) surrounding the tube joint section and housing the front ends (222) of a tank body section (22), which are located close to the core plate; and sloped sections (215) for connecting the tube joint section and the receiving and housing sections and sloped relative to the longitudinal direction of the tube (21). Each of the sloped sections is provided to the core plate so that a first virtual line (VL1) which rectilinearly extends along the sloped section from a receiving and housing section toward the tube joint section and a second virtual line (VL2) which rectilinearly extends along the tube joint section in the direction of the major radius of a cross-section of the tube will intersect outside the tube in the direction of the width of the tube.

Description

Heat exchanger Cross-reference to related applications

This application is based on Japanese Application No. 2015-142835 filed on July 17, 2015, the contents of which are incorporated herein by reference.

The present disclosure relates to a heat exchanger and is suitable for a radiator that cools cooling water of a water-cooled internal combustion engine.

Conventionally, a heat exchanger includes a core portion configured by alternately laminating a plurality of tubes and a plurality of corrugated fins, a header tank that is joined to an end portion in a longitudinal direction of the tube, and communicates with the tube. . The header tank includes a core plate into which a tube is inserted and joined, and a tank main body part that is fixed to the core plate and forms an internal space of the header tank together with the core plate. The core plate has a flat surface on the inner side of the header tank, a tube joint portion provided with a tube insertion hole into which a plurality of tubes are inserted, and a groove portion provided outside the tube joint portion to receive the end of the tank main body portion. Is provided.

In this type of heat exchanger, when a temperature difference occurs between adjacent tubes, the tube joint portion of the core plate is deformed and stress is concentrated on the end portion in the width direction of the tube. is there.

Therefore, for example, in Patent Document 1, a portion on the edge side in the tube width direction at the periphery of the tube insertion hole is formed to protrude upward. By adopting such a shape, Patent Document 1 attempts to improve the strength on the end side in the width direction of the tube.

International Publication No. 2014/180865

By the way, in a heat exchanger such as a radiator mounted on a vehicle, it is desired to reduce the thickness in the width direction of the tube, which is the air flow direction, as much as possible due to restrictions on mounting. In order to realize such a demand, it is necessary to reduce the thickness in the width direction of the tube of the core plate in the heat exchanger.

Here, FIG. 12 shows a schematic cross-section of the core plate studied first by the present inventors. Moreover, FIG. 13, FIG. 14 has shown the typical cross section of the core plate which the present inventors examined 2nd. Hereinafter, the configuration illustrated in FIG. 12 is referred to as Study Example 1, and the configuration illustrated in FIGS. 13 and 14 is referred to as Study Example 2.

As shown in Study Example 1 in FIG. 12, when the thickness in the width direction WD of the tube TB of the core plate CP1 is simply reduced (Lw1 → Lw2), the opposing wall surfaces of the core plate CP1 and the tube TB in the width direction of the tube TB. Each other approaches.

For this reason, when the tube TB and the core plate CP1 are brazed and joined, the brazing material easily goes around not only between the periphery of the tube insertion hole TBh but also between the opposing wall surfaces of the core plate CP1 and the tube TB. . As a result, the tube TB and the core plate CP1 may be joined at an unintended position.

On the other hand, as shown in Study Example 2 in FIG. 13, the present inventors have studied a configuration in which the distance between the opposing wall surfaces of the core plate CP2 and the tube TB is increased except for the periphery of the tube insertion hole TBh. Yes. That is, as shown in FIG. 14, a configuration in which an inclined portion Ci is provided between the joint portion Cj of the tube TB in the core plate CP2 and the portion Ct that receives the tank main body portion is examined. According to this, even if the thickness of the tube TB in the width direction WD of the core plate CP2 in the heat exchanger is reduced, it is possible to avoid the tube TB and the core plate CP2 being joined at an unintended position.

However, when the prototype shown in FIG. 14 was actually prototyped, it was found that a depression (that is, sink) Cs was formed at the peripheral edge portion of the tube insertion hole TBh in the core plate CP2. Such an unintended depression Cs is caused by the brazing material being unstable when brazing and joining the tube TB and the core plate CP2, and the joining state between the tube TB and the core plate CP2 becoming unstable. Is not preferable.

Therefore, the present inventors investigated the cause of the formation of the depression Cs in the core plate CP2. As a result, in the configuration shown in Study Example 2, the tube insertion hole TBh is formed in a part of the inclined portion Ci of the core plate CP2 having a thickness larger than that of the tube joint portion Cj, and the tube insertion hole TBh is formed. It was found that the depression Cs was formed by the molding shrinkage.

This disclosure is intended to provide a heat exchanger that can suppress the occurrence of unintended depressions in the core plate even if the thickness of the core plate in the width direction of the tube is reduced.

According to one aspect of the present disclosure, a heat exchanger includes a core portion having a plurality of flat tubes arranged in a stacked manner, a header tank disposed at an end portion in the longitudinal direction of the tubes and communicating with the plurality of tubes. .

The header tank of the heat exchanger is fixed to the core plate with a plurality of tubes brazed together with the longitudinal ends of the tubes inserted into the tube insertion holes, together with the core plate. A tank main body that forms a space communicating with the plurality of tubes.

The core plate includes a tube joint portion in which a plurality of tube insertion holes are formed, an accommodation receiving portion that surrounds the tube joint portion and accommodates a tip portion close to the core plate in the tank main body portion, and the accommodation receiving portion and the tube joint. And an inclined portion that is inclined with respect to the longitudinal direction of the tube.

The inclined portion includes a first imaginary line that extends linearly along the inclined portion from the housing receiving portion toward the tube joint portion, and a second imaginary line that extends linearly along the tube joint portion in the cross-sectional major axis direction of the tube. The line is provided on the core plate so as to intersect the outside of the tube in the width direction of the tube.

Thus, if it is set as the structure which the 1st imaginary line extended along the inclination part of a core plate and the 2nd imaginary line extended along a tube junction part cross | intersect on the outer side of the width direction of a tube, the width direction of a tube In this case, the inclined portion is formed at a position away from the tube insertion hole. For this reason, it can suppress that a hollow is formed in the peripheral part of the tube insertion hole in a core plate by the shaping | molding shrinkage | contraction at the time of forming a tube insertion hole.

Therefore, according to the heat exchanger of the present disclosure, even if the thickness of the tube in the width direction of the tube in the core plate is reduced, it is possible to suppress an unintended depression in the core plate. As a result, when the tube and the core plate are joined by brazing, the brazing material wraps around stably, so that the joining state between the tube and the core plate can be stabilized.

It is a typical front view of the radiator concerning a 1st embodiment. It is a perspective view of the principal part containing the header tank of the radiator concerning a 1st embodiment. It is a front view of the core plate simple substance of the radiator concerning a 1st embodiment. It is a bottom view of the core plate simple substance of the radiator concerning a 1st embodiment. FIG. 5 is a VV cross-sectional view of FIG. 4. FIG. 6 is a sectional view taken along line VI-VI in FIG. 5. It is sectional drawing which shows the principal part of the core plate of the radiator which concerns on 1st Embodiment. It is explanatory drawing which shows the deformation | transformation state of the core plate of the radiator which concerns on 1st Embodiment. It is explanatory drawing which shows the deformation | transformation state of the core plate of the radiator which concerns on a comparative example. It is a figure which shows the relationship between the distance between tube intersections, and the stress which generate | occur | produces in a tube root part. It is sectional drawing which shows the principal part of the core plate of the radiator which concerns on 2nd Embodiment. It is sectional drawing which shows the state which joined the tube in the core plate of the examination example 1. FIG. It is sectional drawing which shows the state which joined the tube in the core plate of the examination example 2. FIG. It is sectional drawing of the core plate single-piece | unit of examination example 2. FIG.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that, in each of the following embodiments, parts that are the same as or equivalent to the matters described in the preceding embodiment are denoted by the same reference numerals, and the description thereof may be omitted.

In addition, in each embodiment, when only a part of the constituent elements are described, the constituent elements described in the preceding embodiment can be applied to the other parts of the constituent elements.

The following embodiments can be partially combined with each other even if they are not clearly specified, as long as they do not cause any trouble in the combination.

(First embodiment)
The present embodiment will be described with reference to FIGS. This embodiment demonstrates the example which applied the heat exchanger which concerns on this indication to the radiator 1 which cools the water-cooling type internal combustion engine which is mounted in the vehicle which is not shown in figure.

First, the basic configuration of the radiator 1 of the present embodiment will be described with reference to FIG. As shown in FIG. 1, the radiator 1 includes a core portion 10 that is a heat exchange portion that exchanges heat of cooling water of an internal combustion engine (not shown) with outside air. The core part 10 is configured by a laminated body in which a plurality of tubes 11 and fins 12 are alternately laminated in the vertical direction. Hereinafter, in the present embodiment, the stacking direction of the tubes 11 and the fins 12 is referred to as a tube stacking direction YD.

Each tube 11 has a flow path through which cooling water of an internal combustion engine (not shown) flows. Each tube 11 of the present embodiment is configured in a flat shape so that the longitudinal direction thereof extends along the horizontal direction, and the direction in which the cross section has a long diameter (that is, the cross section long diameter direction) extends along the flow direction of the outside air. Has been.

Here, the flat shape refers to an elliptical shape composed of a curved shape obtained by combining an arc portion having a large curvature radius and an arc portion having a small curvature radius, an oval shape comprising a shape obtained by combining an arc portion and a flat portion, and the like. It is included. In the present embodiment, for convenience of explanation, the longitudinal direction of the tube 11 is referred to as a tube longitudinal direction XD, and the direction orthogonal to the tube longitudinal direction XD and the tube stacking direction YD is referred to as a tube width direction ZD. Note that the tube width direction ZD of the present embodiment is a direction that coincides with the direction in which the tube 11 becomes the major axis (that is, the cross-sectional major axis direction).

The fin 12 is a member that increases the heat transfer area with the outside air and promotes heat exchange between the outside air and the cooling water. The fins 12 of the present embodiment are formed in a corrugated shape and are joined to the flat surfaces on both sides of the tube 11. Note that the flat surface used in the present embodiment means a substantially flat state. That is, the flat surface used in the present embodiment includes a state including minute steps, irregularities, and the like that are formed in manufacturing. The same applies to the flat surface of the tube joint portion 211 and the flat surface of the inclined portion 215 described later.

Each tube 11 and fin 12 of the present embodiment are made of a metal (for example, an aluminum alloy) excellent in thermal conductivity, corrosion resistance, and the like. In the radiator 1 of the present embodiment, each tube 11, fins 12, a core plate 21 to be described later, and a side plate 40 to be described later are integrally brazed and joined by a brazing material coated at a predetermined position of each member.

A pair of header tanks 20 and 30 extending in the tube stacking direction YD and having a space formed therein are disposed at both ends of the tube 11 in the tube longitudinal direction XD. Each header tank 20 and 30 is joined in a state in which the end portion of each tube 11 in the tube longitudinal direction XD is inserted into a tube insertion hole 211a of the core plate 21 described later. The internal passage in each tube 11 communicates with a space formed inside each header tank 20, 30.

Among the pair of header tanks 20 and 30, one header tank constitutes an inlet side tank 20 that distributes and supplies high-temperature cooling water flowing out from an internal combustion engine (not shown) to each tube 11. The inlet side tank 20 is provided with an inlet pipe 20a connected to the outlet side of the cooling water of the internal combustion engine via a hose (not shown).

Among the pair of header tanks 20 and 30, the other header tank constitutes an outlet side tank 30 that collects and collects cooling water cooled by heat exchange with the outside air in the core 10. The outlet side tank 30 is provided with an outlet pipe 30a connected to the cooling water inlet side of the internal combustion engine via a hose (not shown).

Side plates 40 that reinforce the core portion 10 are disposed at both ends of the core portion 10 in the tube stacking direction YD. The side plate 40 extends along the tube longitudinal direction XD, and both ends thereof are connected to the header tanks 20 and 30. The side plate 40 of the present embodiment is made of a metal such as an aluminum alloy.

Subsequently, the detailed structure of each of the header tanks 20 and 30 will be described with reference to FIGS. As shown in FIG. 2, each header tank 20, 30 has a core body 21 that forms an internal space 20 b of each header tank 20, 30 together with the core plate 21 and the core plate 21 that are joined together with the tube 11 inserted. 22 and packing 23.

The core plate 21 of the present embodiment is made of a metal (for example, an aluminum alloy) excellent in thermal conductivity, corrosion resistance, and the like. In addition, the tank body 22 of the present embodiment is formed of a resin such as glass reinforced polyamide reinforced with glass fibers. Further, the packing 23 is made of elastically deformable rubber. The packing 23 may be formed of, for example, silicon rubber or EPDM (that is, ethylene / propylene / diene rubber).

In this embodiment, in a state where the packing 23 is sandwiched between the core plate 21 and the tank main body 22, the tank plate 22 is plastically deformed so as to press a protruding piece 213 of the core plate 21 described later against the tank main body 22. The main body 22 is caulked and fixed to the core plate 21.

The core plate 21 has a tube joint portion 211 for joining the tube 11, and a housing receiving portion 212 for housing a flange portion 222 and a packing 23 of the tank main body portion 22 described later around the tube joint portion 211.

The accommodation receiving part 212 has two wall surfaces and is configured in an L shape. That is, the housing receiving portion 212 is a bottom wall portion 212a extending in the tube width direction ZD when viewed from the tube stacking direction YD, and an outer wall portion bent in an L shape from the bottom wall portion 212a and extending in the tube longitudinal direction XD. 212b. Further, as shown in FIG. 3, a plurality of protruding pieces 213 for caulking are formed at the end of the outer wall portion 212 b of the housing receiving portion 212.

As shown in FIG. 4, the tube joining portion 211 has a plurality of tube insertion holes 211a for brazing and joining in a state where the end portions in the tube longitudinal direction XD of each tube 11 are inserted in the tube stacking direction YD. It is formed to line up at intervals.

Here, FIG. 5 is a diagram showing a cross-sectional shape of the core plate 21 when a portion including the tube insertion hole 211a in the tube joint portion 211 is cut in the tube longitudinal direction XD. FIG. 6 is a diagram showing a cross-sectional shape of the core plate 21 when a portion located between the tube insertion holes 211a in the tube joint portion 211 is cut in the tube longitudinal direction XD.

As shown in FIG. 5, a burring portion 211 b that protrudes toward the inner space of each header tank 20, 30 is formed in a portion extending in the tube width direction ZD in the peripheral portion of the tube insertion hole 211 a. . The burring portion 211 b is provided to increase the rigidity of the peripheral edge portion of the tube insertion hole 211 a in the core plate 21.

As shown in FIG. 6, the tube joining portion 211 is located between the adjacent tube insertion holes 211 a, and in the tube width direction ZD of each tube 11, the tube length of each tube 11. A rib 214 that is recessed away from the end in the direction XD is formed.

The ribs 214 are formed so as to overlap the ends of the tubes 11 in the tube width direction ZD in the tube longitudinal direction XD when viewed from the tube stacking direction YD (that is, the direction perpendicular to the paper surface of FIGS. 5 and 6). ing.

In the core plate 21 of the present embodiment, the tube joint portion 211 and the housing receiving portion 212 are connected via an inclined portion 215 that is inclined with respect to the tube longitudinal direction XD. Thereby, as for the core plate 21, the site | part between the tube junction part 211 and the bottom wall part 212a of the accommodating receiving part 212 becomes a stepped shape.

The inclined portion 215 of the present embodiment is inclined so that the interval with the tube 11 in the tube width direction ZD becomes narrower from the bottom wall portion 212a side of the housing receiving portion 212 toward the tube joint portion 211 side.

Here, according to the knowledge of the present inventors, if the tube insertion hole 211a overlaps with a part of the inclined portion 215 in the tube longitudinal direction XD, the tube insertion hole 211a has an intention to the peripheral portion of the tube insertion hole 211a. It has been found that dents that are not easily formed.

Therefore, in this embodiment, the shape of the inclined portion 215 is set so that a part of the inclined portion 215 does not overlap the tube insertion hole 211a in the tube longitudinal direction XD.

Specifically, as shown in FIG. 7, the inclined portion 215 includes a first imaginary line VL <b> 1 that extends linearly along the inclined portion 215 and a second imaginary line VL <b> 2 that extends linearly along the tube joint portion 211. Are formed so as to intersect outside the tube width direction ZD of the tube 11. In other words, the inclined portion 215 of the present embodiment is formed on the core plate 21 so that the intersection A between the first virtual line VL1 and the second virtual line VL2 is located outside the tube width direction ZD of the tube 11. Has been.

Here, the first virtual line VL1 is a straight line extending along the flat surface of the inclined portion 215, and is a straight line indicated by a one-dot chain line in FIG. Specifically, the first virtual line VL <b> 1 is a straight line extending linearly along the inclined portion 215 from the housing receiving portion 212 toward the tube joint portion 211. As described above, the flat surface of the inclined portion 215 means that it is in a substantially flat state, and includes a minute step, unevenness or the like that is formed in manufacturing. Also good.

Further, the second virtual line VL2 is a straight line extending along the flat surface of the tube joint portion 211, and is a straight line indicated by a two-dot chain line in FIG. Specifically, the second imaginary line VL <b> 2 is a straight line that extends linearly along the tube joint portion 211 in the direction of the long diameter in the cross section of the tube 11 (that is, the cross section long diameter direction). As described above, the flat surface of the tube joint portion 211 means a substantially flat state, and includes a minute step, unevenness, etc. that are formed in manufacturing. May be.

Returning to FIG. 2, the tank body 22 of the present embodiment has a length in the tube width direction ZD shorter than a length in the tube width direction of the tube 11 in order to reduce the thickness of the radiator 1 in the tube width direction ZD. It has the part which becomes. And the bulging part 221 which swelled in the direction away from the tube 11 in the tube width direction ZD is provided in the site | part which opposes the tube 11 in the tank main-body part 22. As shown in FIG. Thereby, the inside of the tank main body 22 is configured not to contact the tube 11.

Further, the tank main body portion 22 of the present embodiment is provided with a flange portion 222 having a thickness larger than that of other portions at a tip portion close to the core plate 21. The flange portion 222 is disposed on the receiving portion 212 of the core plate 21 via the packing 23.

Next, an outline of a method for manufacturing the radiator 1 having the above configuration will be described. The manufacturing method of the radiator 1 of the present embodiment includes a preparation process, a temporary assembly process, and a brazing joining process. First, in a preparation process, each component which comprises the radiator 1 is prepared. This preparation step includes a step of forming the core plate 21 having the tube joint portion 211, the receiving portion 212, the protruding piece 213, and the rib 214. In the present embodiment, the tube insertion hole 211a is formed on the flat surface of the tube joint portion 211 by punching a plate-shaped metal material (for example, punching).

Subsequently, in the temporary assembly process, the core portion 10 and the like are temporarily assembled by assembling the tube 11, the fins 12, and the side plate 40 prepared in the preparation process in the tube stacking direction YD on the work table.

In the temporary assembly process, after the core plate 21 in which the tube insertion hole 211a is formed is assembled to the core portion 10, the assembled state is maintained by a jig such as a wire. Subsequently, in the brazing and joining step, the assembly of the state in which the core plate 21 is assembled to the core portion 10 is placed in a heated furnace, so that each element of the core plate 21 and the core portion 10 is brazed. To join.

After completion of the brazing and joining process, the packing 23 is accommodated in the accommodation receiving portion 212 of the core plate 21. Then, in a state in which the flange portion 222 of the tank main body portion 22 is accommodated in the accommodation receiving portion 212 of the core plate 21 in which the packing 23 is accommodated, the projecting pieces 213 of the core plate 21 are plastically deformed by pressing or the like, The tank body 22 is caulked and fixed to the core plate 21.

Subsequently, the manufacturing of the radiator 1 is completed through inspection processes such as leakage inspection and dimension inspection. In the leakage inspection or the like, it is confirmed whether or not there is a brazing defect or a caulking defect at the joint portion of the radiator 1.

The radiator 1 of the present embodiment described above has the following effects by having the above-described configuration. That is, the radiator 1 according to the present embodiment is configured to connect the tube joining portion 211 of the core plate 21 and the bottom wall portion 212a of the housing receiving portion 212 via the inclined portion 215. According to this, even if the thickness of the core plate 21 in the radiator 1 in the tube width direction ZD is reduced, the tube 11 and the core plate 21 can be prevented from being joined at an unintended position.

In particular, in the present embodiment, as shown in FIG. 7, the first imaginary line VL <b> 1 extending along the inclined portion 215 and the second imaginary line VL <b> 2 extending along the tube joint portion 211 are in the tube width direction of the tube 11. The inclined portion 215 is formed so as to intersect outside the ZD. According to this, in the tube width direction ZD, the inclined portion 215 is formed at a position away from the tube insertion hole 211a. For this reason, it can suppress that a hollow is formed in the peripheral part of the tube insertion hole 211a in the core plate 21 by the shaping | molding shrinkage | contraction at the time of forming the tube insertion hole 211a.

Therefore, according to the radiator 1 of the present embodiment, it is possible to suppress an unintended depression in the core plate 21 even if the thickness of the core plate 21 in the tube width direction ZD is reduced. As a result, when the tube 11 and the core plate 21 are brazed and joined, the brazing material wraps around stably, so that the joined state between the tube 11 and the core plate 21 can be stabilized.

Here, when a temperature difference occurs between the adjacent tubes 11, as shown in FIG. 8, the core plate 21 may be deformed like a bow due to the tube 11 on the high temperature side extending in the tube longitudinal direction XD. In this case, stress concentrates on the end of the tube 11 in the tube width direction ZD.

Therefore, in the present embodiment, the tube 11 is located between the adjacent tube insertion holes 211a in the core plate 21 and located on the end portion side in the width direction of the tube 11 from the end portion of the tube 11 in the tube longitudinal direction XD. A recessed rib 214 is formed.

With such a configuration, when a temperature difference occurs between the adjacent tubes 11, deformation of the end portion in the tube width direction ZD in the tube insertion hole 211a, that is, thermal strain can be suppressed by the rib 214. For this reason, it is possible to prevent stress concentration from occurring at the end of the tube 11 in the tube width direction ZD.

By the way, the stress concentration generated in the end portion of the tube 11 in the tube width direction ZD is also alleviated by the deformation of the inclined portion 215 located outside the tube width direction ZD around the intersection A. That is, when a temperature difference occurs between the adjacent tubes 11, the stress generated at the end of the tube 11 in the tube width direction ZD is absorbed by the deformation of the inclined portion 215.

However, as shown in the comparative example of FIG. 9, in the configuration in which a part of the inclined portion 215 overlaps the tube insertion hole 211a in the tube longitudinal direction XD, the volume of the portion that absorbs stress in the inclined portion 215 decreases. As a result, the effect of reducing the stress generated at the end portion of the tube 11 in the tube width direction ZD due to the deformation of the inclined portion 215 cannot be sufficiently obtained.

Therefore, the inventors of the present invention have the stress acting on the end of the tube 11 in the tube width direction ZD at the position of the tube 11 and the intersection A of the first imaginary line VL1 and VL2 in the tube width direction ZD. The effective range for reducing concentration was examined.

FIG. 10 is a diagram showing the examination results of the effective range for reducing the stress concentration acting on the tube root portion Tb with respect to the distance Lta between the tube root portion Tb that is the end portion of the tube 11 in the tube width direction ZD and the intersection A. It is.

Here, the horizontal axis of FIG. 10 indicates the distance between the tube root portion Tb and the intersection A, that is, the tube intersection distance Lta. On the other hand, the vertical axis in FIG. 10 represents the ratio of the generated stress with the stress acting on the tube root portion Tb being 100% when the tube intersection distance Lta is zero.

10, the triangular plot in the figure shows the relationship between the tube intersection distance Lta and the generated stress ratio when the inclination angle θ of the inclined portion 215 is 15 °. Further, the square plot in the figure shows the relationship between the tube intersection distance Lta and the generated stress ratio when the inclination angle θ of the inclined portion 215 is 20 °. Further, the rhombus plot in the figure shows the relationship between the tube intersection point distance Lta and the generated stress ratio when the inclination angle θ of the inclined portion 215 is 40 °. Note that the inclination angle θ is an angle formed by the inclined portion 215 and the tube longitudinal direction XD as shown in FIG.

As shown in FIG. 10, when the tube intersection distance Lta is in the range of 0.0 to 2.4 [mm] (that is, 0.0 ≦ Lta ≦ 2.4), it acts on the tube root portion Tb. It was found that the stress to be reduced. It has also been found that this tendency is the same even if the inclination angle θ of the inclined portion 215 is changed.

Here, as in the comparative example of FIG. 9, in the configuration in which the distance Lta between the tube intersections is negative, a part of the inclined portion 215 overlaps the tube insertion hole 211a in the tube longitudinal direction XD. For this reason, it is thought that the effect of reducing the stress acting on the tube root portion Tb cannot be sufficiently obtained by increasing the strength of the inclined portion 215.

Further, in the configuration in which the tube intersection distance Lta exceeds 2.4 [mm], the thickness between the inclined portion 215 and the tube 11 in the tube width direction ZD becomes large. For this reason, it is thought that the effect of reducing the stress acting on the tube root portion Tb cannot be sufficiently obtained by increasing the strength of the inclined portion 215.

In this way, when the inclined portion 215 is viewed from the tube stacking direction YD, the distance between the intersection A between the first virtual line VL1 and the second virtual line VL2 and the tube root portion Tb is 0.0-2. It is desirable to provide the core plate 21 so as to be in the range of 4 mm.

If the distance Lta between the tube intersections is in the range of 0.0 to 2.4 mm, the end of the tube 11 in the tube width direction ZD is deformed even if a temperature difference occurs between the adjacent tubes 11. It can be effectively suppressed.

Here, the ratio of generated stress when the tube intersection distance Lta is 0.0 is 100% or less, but is close to 100%. For this reason, the inclined portion 215 is more preferably provided on the core plate 21 so that the distance Lta between the tube intersections is greater than 0.0 mm and equal to or less than 2.4 mm.

In addition, when the distance Lta between the tube intersections is in the range of 0.4 to 1.9 mm, the generated stress ratio is less than 80%, so that the deformation of the end of the tube 11 in the tube width direction ZD can be reliably suppressed. it can.

Furthermore, when the tube intersection distance Lta is in the range of 0.6 to 1.3 mm, the ratio of generated stress is less than 60%, so that the deformation of the end portion of the tube 11 in the tube width direction ZD can be more reliably suppressed. Can do.

Here, in the present embodiment, the flange portion 222 constituting the front end portion of the tank main body portion 22 is configured to be caulked and fixed by the protruding piece 213 of the core plate 21. In such a configuration, there is a concern that stress is concentrated on the end side in the tube width direction ZD of the tube insertion hole 211a when the crimping is fixed.

For this reason, in the configuration in which the flange portion 222 constituting the tip portion of the tank main body portion 22 is caulked and fixed by the protruding piece 213 of the core plate 21, it is preferable to employ the core plate 21 of the present embodiment described above.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. FIG. 11 is a cross-sectional view showing the main part of the core plate 21.

As shown in FIG. 11, in this embodiment, a depression 216 is intentionally provided so that a step is formed between the inclined portion 215 and the tube joint portion 211. The recess 216 is provided to form a brazing reservoir for accumulating brazing material between the tube 11 and the inclined portion 215 when the tube 11 and the core plate 21 are joined by brazing.

Other configurations are the same as those in the first embodiment. According to the structure of this embodiment, in addition to the effect demonstrated in 1st Embodiment, there exist the following effects. That is, in this embodiment, since the recess 216 is formed between the inclined portion 215 and the tube joint portion 211, the joint strength between the end portion of the tube 11 in the tube width direction ZD and the core plate 21 is increased. Can do. Therefore, it is possible to more reliably suppress the deformation of the end portion of the tube 11 in the tube width direction ZD when a temperature difference occurs between the adjacent tubes 11.

(Other embodiments)
As mentioned above, although embodiment of this indication was described, this indication is not limited to the above-mentioned embodiment, and can change suitably. For example, various modifications are possible as follows.

(1) Although it is desirable to provide the burring part 211b and the rib 214 with respect to the tube joining part 211 like each above-mentioned embodiment, it is not limited to this, It is good also as a structure which does not provide the burring part 211b and the rib 214. .

(2) In each of the above-described embodiments, the example in which the bulging portion 221 is provided in the portion of the tank main body portion 22 that faces the tube 11 is described. However, the present invention is not limited to this, and the bulging portion 221 is not provided. Also good.

(3) In each of the above-described embodiments, the example in which the heat exchanger of the present disclosure is applied to the radiator 1 has been described. However, the present invention is not limited to this. For example, the heat exchanger of the present disclosure may be applied to a refrigerant evaporator or refrigerant radiator of a vapor compression refrigeration cycle, an intercooler that cools intake air of an internal combustion engine, or the like.

(4) In the above-described embodiment, the elements constituting the embodiment are not necessarily essential unless explicitly stated as essential and clearly considered essential in principle. Needless to say.

(5) In the above-described embodiment, when numerical values such as the number, numerical value, quantity, range, etc. of the constituent elements of the embodiment are mentioned, it is clearly indicated that it is particularly essential and clearly specified in principle. It is not limited to the specific number except in a limited case.

(6) In the above-described embodiment, when referring to the shape, positional relationship, etc. of the component, etc., the shape, unless otherwise specified and in principle limited to a specific shape, positional relationship, etc. The positional relationship is not limited.

Claims (5)

A heat exchanger,
A core portion (10) having a flat tube (11) arranged in a plurality of layers;
A header tank (20, 30) disposed at an end in the longitudinal direction (XD) of the tube and communicating with the plurality of tubes;
The header tank is
A core plate (21) in which the plurality of tubes are brazed and joined in a state where the longitudinal ends of the tubes are inserted into the plurality of tube insertion holes (211a);
A tank body (22) that is fixed to the core plate and forms a space that communicates with the plurality of tubes together with the core plate.
The core plate is
A tube joint portion (211) in which the plurality of tube insertion holes are formed;
An accommodation receiving portion (212) for enclosing the tube joint portion and accommodating a tip portion (222) in the tank main body portion adjacent to the core plate;
The housing receiving portion and the tube joint portion are connected, and an inclined portion (215) that is inclined with respect to the longitudinal direction of the tube,
The inclined portion includes a first imaginary line (VL1) extending linearly along the inclined portion from the housing receiving portion toward the tube joint portion, and along the tube joint portion in the cross-sectional major axis direction of the tube. The heat exchanger provided in the said core plate so that the 2nd virtual line (VL2) extended linearly may cross | intersect on the outer side of the said tube in the width direction of the said tube. In the tube joint portion, the plurality of tube insertion holes are formed so as to be arranged at a predetermined interval in the stacking direction of the tubes, and between the adjacent tube insertion holes, the width of the tube The heat exchanger according to claim 1, wherein a rib (214) that is recessed away from an end portion in the longitudinal direction of the tube is formed at a portion that is located on an end portion side in the direction. In the tube stacking direction, when the distance between the intersection (A) of the first imaginary line and the second imaginary line and the end in the width direction of the tube is the distance between the tube intersections (Lta),
The heat exchanger according to claim 1 or 2, wherein the inclined portion is provided on the core plate so that a distance between the tube intersections is in a range of 0.0 to 2.4 mm. In the tube stacking direction, when the distance between the intersection of the first imaginary line and the second imaginary line (A) and the end of the tube in the width direction is the distance between the tube intersections (Lta),
The heat exchanger according to claim 1 or 2, wherein the inclined portion is provided on the core plate so that a distance between the tube intersections is greater than 0.0 mm and not more than 2.4 mm. The heat exchanger according to any one of claims 1 to 4, wherein the front end portion of the tank body portion is caulked and fixed to the core plate in a state of being accommodated in the accommodation receiving portion.

Images