JP2004347159A - Heat exchanger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger having protruded portions formed inside a tube for improving heat exchanging performance and tube pressure resistance, wherein the tube is kept sufficiently rigid by setting the depths of recessed portions to be formed in the outer faces of the tube such that no poor brazing occurs between the tube and a header tank for producing good brazing performance therebetween while reducing manufacturing cost for the tube. <P>SOLUTION: An oval recessed portion 20a and a circular recessed portion 21a are formed in the outer faces of an upper side wall 10 and a lower side wall 11 of the tube 20, respectively, and an oval protruded portion 20b and a circular protruded portion 21b corresponding to the recessed portions 20a, 21a are formed on the inner faces thereof, respectively. The depths of the recessed portions 20a, 21a are each 0.3mm and a gap is formed between the front end faces of each of the oval protruded portions 20a, 20b and each of the circular protruded portions 21b, 21b opposing each other. A sheet member 30 is inserted into the gap and held between the protruded portions 20b, 21b. The protruded portions 20b, 21b are brazed at their front end faces to the sheet member 30. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to, for example, a heat exchanger used for a condenser, an evaporator, and the like that constitute one element of a refrigeration cycle of an air conditioner.
[0002]
[Prior art]
Conventionally, as a heat exchanger of this type, a plurality of flat tubes having a refrigerant flow path cross section long in the air flow direction are arranged side by side in a direction intersecting the air flow direction, and these tube ends are formed in a header tank. There has been known a device in which the tube is inserted into a tube insertion hole and brazed to the periphery of the tube insertion hole (for example, see Patent Document 1).
[0003]
In Patent Literature 1, a large number of small circular protrusions protrude from the inner surface of the opposite wall of the tube, and the heat exchange performance is enhanced by causing the refrigerant flowing in the tube to collide with the protrusion and disturb the flow. Like that. Further, the opposing projections are integrated by brazing, so that the pressure resistance of the tube is sufficiently obtained.
[0004]
By the way, in Patent Document 1, since a tube is obtained by press-forming or roll-forming a plate material, for example, a plurality of concave portions corresponding to the protruding portions are formed on the outer surface of the opposing wall of the tube. Since this concave portion is also formed at both ends of the tube, the concave portion may overlap with the periphery of the tube insertion hole of the header tank. In this case, if the concave portion depth is equal to or more than a predetermined depth, the concave portion of the tube is formed. In some cases, the brazing material that has flowed between the tube and the periphery of the tube insertion hole separates from the brazing surface and solidifies, resulting in poor brazing. Therefore, in a heat exchanger in which a concave portion is formed in the opposed wall of the tube, there is one in which the outer surface of the opposed wall is flattened only at the end of the tube to prevent brazing failure (for example, see Patent Documents 2 and 3). ).
[0005]
In Patent Document 2, the outer surface of the opposing wall is flattened by omitting a concave portion and a protrusion at the tube end. In Patent Document 3, an annular plate member having a flat outer peripheral surface is fitted to the tube end. Then, the outer peripheral surface of the plate member is brazed to the periphery of the tube insertion hole.
[0006]
[Patent Document 1]
JP-A-7-227631 (pages 4 and 5, FIGS. 2 and 3)
[Patent Document 2]
JP-A-10-332294 (page 3, FIG. 1, FIG. 4)
[Patent Document 3]
JP-A-11-264686 (pages 5, 6, FIG. 7, FIG. 10)
[0007]
[Problems to be solved by the invention]
However, in the heat exchanger of Patent Literature 2, since the shape of the tube end and the shape of the intermediate portion are different, unless the mold of the tube is changed between a plurality of types of heat exchangers having different tube lengths. Instead, the manufacturing cost rises. Further, in the heat exchanger of Patent Document 3, since the plate member is externally fitted to the end of the tube, the number of parts increases, the number of steps for assembling the tube increases, and the manufacturing cost increases.
[0008]
Therefore, it is conceivable to reduce the thickness of the tube of Patent Document 1 to reduce the projection height of the projection, that is, the depth of the recess, and thereby to set the depth of the recess to such an extent that brazing failure does not occur. Can be By setting the depth of the recess in this way, it is not necessary to change the outer surface shape of the tube end portion with respect to the intermediate portion, and the entire length direction of the tube can be the same shape, for example, formed into a long shape If the tubes are cut in accordance with the tube length of each heat exchanger, the mold for forming the tubes can be shared between a plurality of types of heat exchangers, and a plate member as described in Patent Document 3 is required. And the manufacturing cost can be reduced. However, when the thickness of the tube is reduced, the rigidity of the tube is reduced, and the tube is easily deformed at the time of assembly or the like.
[0009]
The present invention has been made in view of such a point, and an object of the present invention is to form a protrusion on the inner surface of a facing wall of a tube to improve heat exchange performance and pressure resistance of the tube. In the vessel, the depth of the recess formed on the outer surface of the opposing wall is set to a depth that does not cause brazing failure between the tube and the header tank, thereby improving the brazing property of both tubes while reducing the manufacturing cost of the tube. In this case, it is to secure sufficient rigidity of the tube.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, the sheet member is sandwiched between the opposed protrusions of the tube, and the sheet member is fixed to the protrusion.
[0011]
Specifically, the invention according to claim 1 includes a flat tube in which a refrigerant passage having a cross section long in the air flow direction is formed, and a header tank disposed at an end of the tube and communicating with the tube. The end of the tube is inserted into a tube insertion hole formed in the header tank and brazed to the periphery of the tube insertion hole, and a plurality of recesses are formed on the outer surface of the opposing wall that intersects with the air flow direction of the tube. A plurality of protrusions are formed on the inner surface of the opposed wall corresponding to each of the concave portions so as to project toward the coolant flow path so as to face each other, and a sheet member is sandwiched and fixed to the opposed protrusions. Configuration.
[0012]
According to this configuration, the flow of the refrigerant in the tube is disturbed by the protrusion formed on the tube, and the heat exchange performance is enhanced. Further, the opposed protrusions are integrated via the sheet member, and the pressure resistance of the tube is increased. .
[0013]
And since the depth of the concave portion of the tube becomes shallower by the dimension corresponding to the thickness of the sheet member, even if the thickness of the tube is set to a thickness that can secure sufficient rigidity, the depth of the concave portion may be insufficiently brazed to the header tank. It can be set to a depth that does not occur. Due to the recess, the brazing material flows between the recess forming portion of the tube end and the periphery of the tube insertion hole during brazing, and the brazing material is solidified without separating from the brazing surfaces of the two. Brazing properties between the portion and the periphery of the tube insertion hole are improved.
[0014]
Also, by setting the depth of the concave portion as described above, the brazing property with the header tank is improved without changing the outer surface shape of the tube end portion with respect to the intermediate portion. It is possible to make the shape of the tube the same.For example, if a long-shaped tube is cut to obtain a tube of a desired length, a tube forming die can be shared between a plurality of types of heat exchangers. In addition to the above, the need for a conventional plate member externally fitted to the end of the tube is eliminated, and the manufacturing cost of the tube can be reduced.
[0015]
According to a second aspect of the present invention, in the first aspect, a brazing material is provided on at least one of the protrusion and a portion of the sheet member facing the protrusion, and the protrusion and the sheet member are brazed. Configuration.
[0016]
According to this configuration, the sheet member is securely fixed to the projection.
[0017]
According to a third aspect of the present invention, in the second aspect, the sheet member is formed in a corrugated plate shape.
[0018]
According to this configuration, when the depth of the concave portion is made shallower by making the gap between the opposing protrusions larger than the thickness of the plate material forming the sheet member, the peak portion of the sheet member has a protrusion. The sheet member is securely brazed by contacting the front end surface. Thereby, the degree of freedom in setting the depth of the concave portion is increased while the sheet member is securely fixed to the protrusion and the pressure resistance of the tube is secured.
[0019]
In addition, by setting the dimension of the wave height direction of the sheet member to be larger than the gap between the opposing protrusions, when the shape of the protrusions is uneven, the sheet member may have the height of the wave. Since the sheet member elastically deforms in the direction to absorb the variation, the sheet member comes into contact with the projections as intended, and the brazing between the projections and the sheet member is ensured.
[0020]
According to a fourth aspect of the present invention, in the third aspect, a gap of 0.3 mm or less is formed between the projection and the sheet member.
[0021]
According to this configuration, the brazing material can easily flow between the protrusion and the sheet member, and the flowed brazing material can be applied to substantially the entire distal end surface of the protrusion and the portion of the sheet member facing the protrusion. Since it is solidified in a widespread state, a sufficient brazing strength between the projection and the sheet member can be obtained.
[0022]
According to a fifth aspect of the present invention, in any one of the second to fourth aspects of the present invention, the tube is made of an aluminum alloy, and a brazing material is provided at a position facing the protrusion of the sheet member, and the air flow of the sheet member is increased. The both ends in the direction are separated from the inner surface of the tube.
[0023]
According to this configuration, the protruding portion and the sheet member are brazed by the brazing material of the sheet member, and the brazing material of the sheet member melted during the brazing does not flow to the inner surface of the tube. Will not be supplied to As a result, the silicon contained in the brazing material does not diffuse more than necessary to the inner surface of the tube, and the thinning and perforation of the tube due to the erosion of the silicon are prevented.
[0024]
According to a sixth aspect of the present invention, in any one of the second to fifth aspects of the present invention, the sheet member is provided with a flux that melts during brazing and removes an oxide film on the surface.
[0025]
According to this configuration, the oxide film on the surface of the sheet member is reliably removed by the flux, and since the flux of the sheet member comes into contact with the tip surface of the projection, the oxide film on the tip surface of the projection is also reliably formed. Since these are removed, the brazing strength between the projections and the sheet member can be sufficiently obtained.
[0026]
Further, when providing the flux on the protrusion, there are two cases: applying the flux to the formed tube and applying the flux to the plate material before the forming. In the former case, it is difficult to apply a flux to the entire tip surface of the protrusion because the inner shape of the tube is more complicated by the protrusion, and in the latter case, the flux generally contains a harder component than the mold. Therefore, there is a problem that the mold is damaged. On the other hand, in the present invention, since it is possible to insert the sheet member provided with the flux layer into the formed tube, it is possible to easily and without damaging the forming die, bring the flux into contact with the tip end surface of the protrusion. Becomes possible.
[0027]
According to a seventh aspect of the present invention, in any one of the second to sixth aspects, the depth of the recess is 0.3 mm or less.
[0028]
According to this configuration, the brazing material easily flows between the recessed portion on the outer surface of the tube and the periphery of the tube insertion hole, and the brazing material spreads over substantially the entire outer surface of the tube end and the periphery of the tube insertion hole. Since it is solidified in a state, sufficient brazing strength between the tube end and the periphery of the tube insertion hole can be obtained.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0030]
In the description of this embodiment, for the sake of convenience, “front” means the front side of the vehicle, “rear” means the rear side of the vehicle, and “left” means the left side of the vehicle. , And “right” means the right side of the vehicle.
[0031]
FIG. 2 shows a heat exchanger according to an embodiment of the present invention. In this example, a case where the heat exchanger is a refrigerant condenser 1 constituting one element of a refrigeration cycle of a vehicle air conditioner is shown. The refrigerant condenser 1 is mounted at the front end of an engine room (not shown) of a vehicle body, and includes a plurality of tubes 2, 2,... Extending in the left-right direction and fins 3, 3,. A core 4 is provided alternately side by side, and a left header tank 7 and a right header tank 8 are disposed at both ends of the tube 2 of the core 4 and communicate with the tubes 2. The core 4 is configured such that cooling air generated by running of a vehicle or rotation of a cooling fan (not shown) in an engine room passes from the front to the rear.
[0032]
As shown in FIGS. 1 and 3, each tube 2 of the core 4 is formed in a rectangular shape whose cross section of the refrigerant flow path is long in the direction of the cooling air flow (indicated by an arrow A in FIGS. 1A and 3). It is a flat tube and is composed of an upper wall 10 and a lower wall 11 facing up and down, and a front wall 12 and a rear wall 13 facing up and down.
[0033]
The tube 2 is formed by roll forming one plate material in which brazing material is provided in layers on both surfaces. The upper side wall 10, the rear side wall 13 and the lower side wall 11 of this tube are continuous, and one side edge and the other side edge of the plate material are engaged at the front wall 12 forming location, and the refrigerant flow path R is formed therein. It is formed. One side edge of the plate material, which is the front end of the lower wall 11 of the tube 2, is bent substantially upward at a right angle, and the leading end thereof is bent 180 ° outward and downward about the refrigerant flow path R, and Have been. On the other hand, the other side edge of the plate material, which is the front end of the upper wall 10 of the tube 2, is bent downward so as to surround the folded portion 14 from the outside of the refrigerant flow path R and engage with the folded portion 14. Has been brazed to. By engaging the two edges of the plate at the position where the front side wall 12 of the tube 2 is formed, the front end of the tube 2 has a thickness in which a plurality of the plates are overlapped, and the tube 2 comes flying when the vehicle travels. The tube 2 is prevented from being damaged by pebbles or the like.
[0034]
A plurality of oblong recesses 20a and a plurality of circular recesses 21a are formed on the outer surface of the upper side wall 10 and the lower side wall 11 of the tube 2, and the inner surfaces of the upper side wall 10 and the lower side wall 11 corresponding to the respective recesses 20a, 21a are formed. Has a plurality of oblong projections 20b and circular projections 21b. The oblong recesses 20a and the oblong projections 20b and the oblong recesses 21a and the oblong projections 21b are alternately arranged at intervals in the longitudinal direction of the tube 2. The elliptical concave portion 20a and the elliptical protrusion 20b are formed in an oval shape that is long in the length direction of the tube 2 in plan view, and are arranged at substantially equal intervals in the width direction of the tube 2 (air flow direction). The circular recesses 21a and the circular protrusions 21b are formed smaller than the oblong recesses 20a and the oblong protrusions 20b, and are substantially arranged so that the tube 2 is located between the adjacent oblong recesses 20a as viewed in the length direction. Three are arranged at equal intervals.
[0035]
The depth X (shown in FIG. 4) of the oblong concave portion 20a and the circular concave portion 21a formed on the upper side wall 10 of the tube 2, that is, the separation dimension between the outer surface of the upper side wall 10 of the tube 2 and the bottom surfaces of the concave portions 20a and 21a is substantially equal. 0.3 mm. The oval concave portion 20a and the circular concave portion 21a formed on the lower side wall 11 have the same depth. In addition, a gap S (shown only in FIG. 4) is formed between the tip surfaces of the oblong protrusions 20b, 20b and the circular protrusions 21b, 21b facing each other up and down.
[0036]
In the gap S of the tube 2, a rectangular sheet member 30 extending substantially in parallel with the upper side wall 10 and the lower side wall 11 is provided. The sheet member 30 is made of a thin plate made of an aluminum alloy having a thickness of about 0.1 mm, and although not shown, substantially the entire upper and lower surfaces of the sheet member 30 are provided with a brazing material in a layered manner. A flux that is melted during brazing and removes an oxide film on the brazing surface is applied to the surface side of the material layer to form a flux layer.
[0037]
The dimension of the sheet member 30 in the length direction of the tube 2 is set substantially equal to the length of the tube 2. On the other hand, the dimension of the sheet member 30 in the width direction of the tube 2 is longer than the interval between the oblong protrusions 20b, 20b located on both sides in the width direction of the tube 2 and is greater than the width of the refrigerant flow path R (the dimension in the air flow direction). Is also set short, and the sheet member 30 is positioned substantially at the center in the width direction of the refrigerant flow path R. As a result, the sheet member 30 is interposed between all the elliptical protrusions 20b, 20b and the distal end surfaces of the circular protrusions 21b, 21b of the tube 2, and both edges of the sheet member 30 in the width direction from the inner surface of the tube 2. You will be away.
[0038]
The gap S between the tubes 2 is formed so that the sheet member 30 can be inserted during or after the tube 2 is formed. Specifically, the gap S is approximately the same as the thickness of the sheet member 30 and is inserted. At this time, the sheet member 30 comes into sliding contact with the distal end surfaces of the elliptical projections 20b and the circular projections 21b. As a result, the inserted sheet member 30 is sandwiched between the opposing elliptical projections 20b, 20b and the circular projections 21b, 21b.
[0039]
On the other hand, as shown in FIG. 3, the fins 3 of the core 4 are corrugated fins formed in a wavy shape that is continuous in the left-right direction when viewed from the air flow direction, and are formed by bending a thin plate made of an aluminum alloy. The distance between the adjacent tubes 2 above and below the core 4 corresponds to the length of the fins 3 above and below, so that the upper and lower ends of the fins 3 are brazed to the outer surface of the adjacent tubes 2. It has become. The fins 3 are positioned at both outer ends in the vertical direction of the core 4, and the upper and lower fins 3 of the core 4 are held by fin holding plates 35, 35, respectively.
[0040]
The left and right header tanks 7 and 8 are formed by forming a plate made of aluminum alloy having brazing material provided in layers on both surfaces in a cylindrical shape, and extend straight from the upper end to the lower end of the core 4. ing. Tube insertion holes 36 corresponding to the outer shape of each tube 2 are formed on the core 4 side of the peripheral walls of the header tanks 7, 8 corresponding to the interval between the tubes 2. The inner peripheral surface of the tube insertion hole 36 is formed so as to increase in diameter toward the outside of the header tanks 7 and 8, and guides the end of the tube 2 at the time of insertion. The outer peripheral surface of the tube 2 and the peripheral edge of the tube insertion hole 36 are brazed in a state where the end of each tube 2 is inserted into the tube insertion hole 36.
[0041]
The upper and lower ends of the left and right header tanks 7, 8 are circularly opened, and these openings are closed by cap members 37 brazed to the outer peripheral surfaces of the header tanks 7, 8 as shown in FIG. Thereby, a hollow portion T communicating with the end of each tube 2 is formed inside. A partition plate 38 for partitioning the hollow portion T into an upper hollow portion T1 and a lower hollow portion T2 is provided substantially at the center of the inside of the right header tank 8 in the vertical direction. The partition plate 38 is a disk member made of an aluminum alloy, is inserted into a slit (not shown) formed in the peripheral wall of the header tank 8, and the outer peripheral edge is brazed to the inner peripheral surface of the header tank 8. .
[0042]
The first path P1 is formed by the tube 2 above the partition plate 38 of the tube 2, and the second path P2 is formed by the tube 2 below the partition plate 38. In addition, an inflow cooler pipe 40 for allowing the refrigerant to flow into the upper hollow portion T1 is connected to the upper end side of the right header tank 8, and the lower end side of the right header tank 8 receives the refrigerant from the lower hollow portion T2. An outflow cooler pipe 41 for outflow is connected.
[0043]
When manufacturing the refrigerant condenser 1 having the above-described configuration, first, the respective members such as the tube 2, the fins 3, and the header tanks 7, 8 are formed. At this time, as for the tube 2, the long tube formed by roll forming is cut to a desired length to obtain the tube 2, and the sheet member 30 to which the flux is adhered from the end opening of the tube 2 is used for the tube 2. It is inserted and arranged in the gap S. Note that the sheet member 30 may be inserted during the formation of the tube 2. Since the sheet member 30 is sandwiched between the opposing elliptical protrusions 20b, 20b and the circular protrusions 21b, 21b, the sheet member 30 does not shift from a predetermined position.
[0044]
Further, after the tube 2 is formed, it is not necessary to apply the flux to the distal end surfaces of the elliptical projections 20b and the circular projections 21b, and it is not necessary to mold the plate to which the flux is applied. The flux comes into contact with the distal end surfaces of the elliptical projections 20b and the circular projections 21b without causing damage to the projections.
[0045]
The tubes 4 and the fins 3 are alternately arranged to form a core 4. After inserting the left and right ends of the tube 2 into the left and right header tanks 7, 8, the members are bound by a jig. Then, each part is brazed by carrying into a furnace and heating.
[0046]
At the time of this brazing, regarding the brazing between the oval projections 20b and the circular projections 21b of the tube 2 and the sheet member 30, the flux is provided on the sheet member 30 in a layered manner. , 21b are in contact with the front end surfaces, so that the flux heated and melted in the furnace flows on the front end surfaces of the projections 20b, 21b and the surface of the sheet member 30, whereby the oxide film on both surfaces is reliably formed. Can be removed. Further, since the brazing material is provided on both the distal end surfaces of the elliptical protrusions 20b and the circular protrusions 21b and the sheet member 30, a sufficient amount of brazing material can be secured. With these, the distal end surfaces of the oblong protrusions 20b and the circular protrusions 21b and the sheet member 30 can be firmly and securely fixed, and the pressure resistance of the tube 2 can be sufficiently ensured.
[0047]
Further, since both widthwise edge portions of the sheet member 30 are separated from the inner surface of the tube 2, the brazing material of the molten sheet member 30 does not flow to the inner surface of the tube 2, and the brazing material is excessively supplied to the inner surface of the tube 2. Never. Thereby, the thinning and perforation of the tube 2 due to the erosion of silicon contained in the brazing material can be prevented.
[0048]
Regarding the brazing of the end of the tube 2 and the periphery of the tube insertion hole 36 of the header tanks 7, 8, the depth of the oblong concave portion 20a and the circular concave portion 21a of the tube 2 is set to approximately 0.3 mm. The brazing material easily flows between the recesses 20a and 21a and the periphery of the tube insertion hole 36, and solidifies in a state where the brazing material has spread over substantially the entire outer surface of the end of the tube 2 and the periphery of the tube insertion hole 36. Thus, brazing properties can be improved. By setting the depth X of the oval concave portion 20a and the circular concave portion 21a in a range of approximately 0.1 mm or more and approximately 0.3 mm or less, brazing is firmly and reliably performed.
[0049]
Further, since the sheet member 30 is interposed between the opposing elliptical projections 20b, 20b and between the circular projections 21b, 21b of the tube 2, the depth X of the elliptical concave portion 20a and the circular concave portion 21a is set to the sheet member 30. Shallower by the dimension corresponding to the thickness of Thereby, even if the thickness Y of the tube 2 is set to a thickness enough to secure sufficient rigidity, the depth X of the oval concave portion 20a and the circular concave portion 21a can be set to approximately 0.3 mm. As a result, it is possible to prevent the tube 2 from being deformed when assembling the tube 2 or attaching the refrigerant condenser 1 to a vehicle while improving the brazing property between the end of the tube 2 and the peripheral edge of the tube insertion hole 36.
[0050]
In addition, by setting the depth X of the oval concave portion 20a and the circular concave portion 21a of the tube 2 to about 0.3 mm as described above, the brazing property with the periphery of the tube insertion hole 36 is improved. It is not necessary to change the outer surface shape of the end portion with respect to the intermediate portion, and the entire shape in the length direction of the tube 2 can be made the same. Thereby, since the tube 2 can be obtained by cutting the long tube as described above, the tube mold can be shared between a plurality of types of refrigerant condensers having different tube lengths. It is not necessary to externally fit the plate member to the end of the tube as in the related art, and the number of components can be reduced. As a result, the manufacturing cost of the tube 2 can be reduced.
[0051]
Next, the flow of the refrigerant in the refrigerant condenser 1 will be described. First, the high-temperature and high-pressure refrigerant discharged from the refrigerant compressor (not shown) flows from the inflow cooler pipe 40 into the upper hollow portion T1 of the right header tank 8. Thereafter, the refrigerant flowing into the upper hollow portion T1 flows to the left through the first path P1 and flows into the left header tank 7, and the refrigerant flowing into the left header tank 7 flows downward and flows through the second path P2 to the right. Flows. The refrigerant flowing through the first path P1 and the second path P2 exchanges heat with the cooling air and gradually condenses. The condensed refrigerant flows into the lower hollow portion T2 of the right header tank 8, and then flows out of the outflow cooler pipe 41 to the outside.
[0052]
When the refrigerant flows through the tubes 2 of the first path P1 and the second path P2, a plurality of oblong protrusions 20b and a plurality of circular protrusions 21b are formed on the upper wall 10 and the lower wall 11 of the tube 2. Therefore, the flow of the refrigerant is disturbed, and the heat exchange efficiency can be increased.
[0053]
In this embodiment, the sheet member 30 is formed in a flat plate shape. However, the present invention is not limited to this. For example, the sheet member 30 may be formed in a corrugated plate shape as in a modification shown in FIG. In this case, even if the gap S between the tubes 2 is made wider than the thickness of the plate member forming the sheet member 30, the crest portion 30a of the sheet member 30 comes into contact with the distal end surfaces of the elliptical projections 20b and the circular projections 21b. The sheet member 30 is brazed to the protrusions 20b and 21b.
[0054]
This makes it possible to increase the gap S and reduce the depths of the oval concave portion 20a and the circular concave portion 21a without causing brazing failure, thereby increasing the degree of freedom in setting the thickness of the tube 2. In addition, by setting the dimension of the sheet member 30 in the height direction of the wave to be larger than the gap S, when the shape of the elliptical protrusion 20b and the circular protrusion 21b has a manufacturing variation. Since the sheet member 30 elastically deforms in the height direction of the wave to absorb the variation, the sheet member 30 comes into contact with the tip surfaces of the projections 20b and 21b as intended, and the sheet member 30 and the projections 20b and 21b The tip surface can be securely brazed.
[0055]
Further, when the sheet member 30 is formed in a corrugated shape in this way, as shown in FIG. 6, the maximum gap W formed between the distal end surfaces of the protrusions 20b and 21b and the sheet member 30 is substantially zero. When the thickness is not less than 0.1 mm and not more than approximately 0.3 mm, the brazing material is more likely to flow between the tip end surfaces of the protrusions 20 b and 21 b and the surface of the sheet member 30, so that the brazing is more reliable and the flowing brazing material is It solidifies over substantially the entire surface on both sides, and sufficient brazing strength is obtained.
[0056]
Further, in this embodiment, the tube 2 is formed of one plate material. However, for example, the upper wall 10 and the lower wall 11 are formed of separate members, and the front edge and the rear edge of each member are engaged with each other. It may be brazed.
[0057]
Further, in this embodiment, the brazing material is provided on both the distal end surfaces of the oblong protrusions 20b and the circular protrusions 21b and the sheet member 30, but the present invention is not limited to this, and the brazing material is provided only on one of them. You may.
[0058]
Further, the concave portion and the projecting portion of the tube 2 may be formed as a concave line and a convex line extending in the longitudinal direction of the tube 2.
[0059]
Furthermore, the present invention can be applied to a heat exchanger such as a radiator of a vehicle.
[0060]
【The invention's effect】
As described above, according to the heat exchanger according to the first aspect of the present invention, the tube end is brazed to the periphery of the tube insertion hole of the header tank, and the projection is provided on the inner surface of the opposed wall of the tube. The flow of the refrigerant inside is disturbed, and the heat exchange performance can be enhanced. Since the sheet member is fixed to the projection by sandwiching the sheet member between the opposed projections, the pressure resistance of the tube can be sufficiently obtained, and the tube is formed on the outer surface of the opposed wall of the tube. Since the depth of the recess becomes shallower by the dimension corresponding to the thickness of the sheet member, even if the thickness of the tube is set to a thickness that can secure sufficient rigidity, the depth of the recess is set to such a degree that brazing failure with the header tank does not occur. Can be set to depth. And by this concave part, the brazing property between the tube end and the periphery of the tube insertion hole can be improved.
[0061]
In addition, since it is possible to make the shape of the entire tube in the longitudinal direction the same while improving the brazing property between the tube end and the periphery of the tube insertion hole, the mold for forming the tube can be formed between a plurality of types of heat exchangers. Can be used in common, and the need for a conventional plate member externally fitted to the end of the tube is eliminated, so that the manufacturing cost of the tube can be reduced.
[0062]
According to the second aspect of the present invention, a brazing material is provided on at least one of the protrusion and the portion of the sheet member facing the protrusion, and the protrusion and the sheet member are brazed. And the sheet member can be securely fixed.
[0063]
According to the third aspect of the present invention, since the sheet member is formed in a corrugated plate shape, the gap between the opposing projections is made larger than the sheet thickness of the sheet member to reduce the depth of the concave portion. In addition, the sheet member is securely fixed to the protruding portion, whereby the degree of freedom in setting the depth of the concave portion can be increased while ensuring the pressure resistance of the tube. Further, in the case where the shape of the protrusion is uneven, the sheet member is elastically deformed to absorb the unevenness, so that the protrusion and the sheet member can be reliably brazed.
[0064]
According to the fourth aspect of the present invention, since a gap of 0.3 mm or less is formed between the protrusion and the sheet member, the brazing material easily flows between the protrusion and the sheet member, and will flow into the brazing material. The material is solidified in a state in which the material spreads over substantially the entirety of the projecting end surface and the portion of the sheet member facing the projecting portion, whereby sufficient brazing strength between the projecting portion and the sheet member can be obtained.
[0065]
According to the invention as set forth in claim 5, the tube is made of an aluminum alloy, a brazing material is provided at a position facing the projection of the sheet member, and both ends of the sheet member in the air flow direction are separated from the inner surface of the tube. At the time of brazing, the brazing material is not excessively supplied to the inner surface of the tube, and it is possible to prevent the tube from being thinned or perforated due to the erosion of silicon of the brazing material.
[0066]
According to the sixth aspect of the present invention, since the flux is provided on the sheet member, the oxide film on the surface of the sheet member and the tip surface of the projection can be reliably removed, and sufficient brazing strength between the projection and the sheet member can be obtained. Can be. Further, by inserting the sheet member into the formed tube, the flux can be provided easily and without damaging the forming die.
[0067]
According to the seventh aspect of the present invention, since the depth of the concave portion is set to 0.3 mm or less, the brazing material easily flows between the concave portion forming portion on the outer surface of the tube and the periphery of the tube insertion hole, and the brazing material is formed into the tube The solidification is performed in a state where the outer surface and the periphery of the tube insertion hole are substantially entirely spread, so that the brazing strength between the tube and the header tank can be sufficiently obtained.
[Brief description of the drawings]
FIG. 1A is a perspective view near the left end of a tube, and FIG. 1B is a left side view of the tube.
FIG. 2 is a front view of the refrigerant condenser according to the embodiment of the present invention as viewed from an upstream side of an air flow.
FIG. 3 is a perspective view of an upper right side of a refrigerant condenser showing a state where a header tank and a core are disassembled.
FIG. 4 is a partially enlarged view of a left end portion of the tube.
FIG. 5 is a diagram corresponding to FIG. 1 according to a modified example.
FIG. 6 is a diagram corresponding to FIG. 4 according to a modification.
[Explanation of symbols]
1 Refrigerant condenser (heat exchanger)
2 tubes
7 Left header tank
8 Right header tank
10 Upper wall
11 Lower wall
20a Oval recess
20b Oval projection
21a Circular recess
21b circular projection
30 sheet members
36 tube insertion hole
R refrigerant flow path
W gap

Claims (7)

A cross-section is provided with a flat tube in which a refrigerant flow path that is long in the air flow direction is formed, and a header tank disposed at the end of the tube and communicating with the tube,
The tube end is inserted into a tube insertion hole formed in the header tank and brazed to a periphery of the tube insertion hole,
A plurality of recesses are formed on the outer surface of the opposing wall that intersects with the air flow direction of the tube. On the inner surface of the opposing wall corresponding to each of the recesses, a plurality of protrusions are directed toward the refrigerant flow path so as to face each other. Protruding,
A heat exchanger, wherein a sheet member is sandwiched and fixed to the opposed projections. In claim 1,
A heat exchanger, wherein a brazing material is provided on at least one of the protrusion and a portion of the sheet member facing the protrusion, and the protrusion and the sheet member are brazed. In claim 2,
A heat exchanger, wherein the sheet member is formed in a corrugated shape. In claim 3,
A heat exchanger, wherein a gap of 0.3 mm or less is formed between the projection and the sheet member. In any one of claims 2 to 4,
The tube is made of aluminum alloy,
A heat exchanger, wherein a brazing material is provided at a position facing the projection of the sheet member, and both end portions in the air flow direction of the sheet member are separated from the inner surface of the tube. In any one of claims 2 to 5,
A heat exchanger, wherein the sheet member is provided with a flux that melts during brazing and removes an oxide film on the surface. In any one of claims 2 to 6,
A heat exchanger, wherein the depth of the concave portion is 0.3 mm or less.

Images