JP7217629B2 - flat multi-hole pipe - Google Patents

Description

TECHNICAL FIELD The present invention relates to a structure of a flat multi-hole tube suitable for use as a heat exchanger tube.

Because aluminum and its alloys are lightweight and have excellent workability and thermal conductivity, they are widely used as fins and tubes for heat exchangers in air conditioners, and heat exchangers are constructed by combining fins and tubes. be able to. As shown in Patent Document 1 below, an all-aluminum type heat exchanger has been developed in which both the fins and tubes are made of aluminum or an aluminum alloy.

In Patent Document 1, a plurality of flat multi-hole pipes arranged vertically so that flat surfaces face each other and having a plurality of refrigerant passages formed therein support a plurality of flat multi-hole pipes adjacent to each other. A heat exchanger is disclosed in which a plurality of fins are joined by brazing to define a flow path through which air flows between perforated tubes.

JP 2012-163317 A

Like the heat exchanger described in Patent Document 1, in a type of heat exchanger that combines fins and flat multi-hole tubes, both ends of a plurality of flat multi-hole tubes are connected to header tubes, and a plurality of flat multi-hole tubes are connected through the header tubes. Refrigerant flows in and out between the multi-hole pipe.
When connecting the ends of a flat multi-hole pipe to a header pipe, both ends of the flat multi-hole pipe may be inserted into slit-shaped connection openings formed in the header pipe, and the inserted portions may be joined by brazing. Here, in order to ensure that the ends of the flat multi-hole pipe can be reliably inserted into the slit-shaped connection openings provided in the header pipe, the width of the end of the flat multi-hole pipe may be slightly reduced by caulking.
When manufacturing a flat multi-hole pipe while performing caulking, it is common to manufacture in the order of extrusion, caulking and cutting.

However, in recent years, with the miniaturization of heat exchangers, multi-hole flat pipes have been introduced with a small size of about several millimeters in both the thickness of each part and the overall thickness. When a flat multi-hole tube is sandwiched by crimping jigs from both ends and crimping is performed, there is a problem that buckling is likely to occur in the crimped portions. Moreover, even if the flow path does not buckle, the stress at the time of caulking concentrates on a part of the flow path, and as a result, there is a possibility that a part of the flow path or the peripheral portion thereof is significantly deformed. A flat multi-hole tube having a crimped portion having a buckling or deformed portion has a problem that it is easy to cause defective brazing during brazing.

The present invention has been made in view of these problems, and it is an object of the present invention to provide a flat multi-hole pipe having a structure in which even if crimping is applied to the end portion, deformation of the crimped portion is unlikely to occur.

(1) The multi-hole flat tube of the present invention comprises a first plate-like wall and a second plate-like wall which are arranged to face each other, a short side wall connecting opposite ends of these plate-like walls in the width direction, A flat multi-hole pipe made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed between the plate-like walls along the width direction of the plate-like walls, and the plate-like walls between the plate-like walls. A flat multi-hole tube having a plurality of flow paths partitioned by the partition along the length direction of the tube, wherein the partition is connected to the first plate-like wall and the second plate-like wall A curved portion is formed so as to form a concave groove on the outer surface side of the plate-like wall and an R ridge on the inner surface side of the plate-like wall along both of the curved portions along the width direction of the plate-like wall on both sides of the plate-like wall and at an intermediate position between the partition walls adjacent in the width direction of the plate-like wall, a ridge portion is formed by outwardly bulging the outer surface of the plate-like wall, and the plate in the partition forming portion The interval between the plate-shaped walls in the ridge portion forming portion is larger than the interval between the shaped walls, and the top of the R projection forming the concave groove is connected to the partition wall on the flow passage side, and the plurality of Of the partition walls, the curved portion is formed corresponding to a part of the partition walls, and a part of the first plate-like wall and a part of the second plate-like wall are formed corresponding to the remaining plurality of partition walls. It is characterized in that a flat plate portion that also serves as a is formed .

(2) The multi-hole flat tube of the present invention includes a first plate-like wall and a second plate-like wall that are arranged to face each other, a short side wall that connects opposite ends of the plate-like walls in the width direction, A flat multi-hole pipe made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed between the plate-like walls along the width direction of the plate-like walls, and the plate-like walls between the plate-like walls. A flat multi-hole tube having a plurality of flow paths partitioned by the partition along the length direction of the tube, wherein the partition is connected to the first plate-like wall and the second plate-like wall A curved portion is formed so as to form a concave groove on the outer surface side of the plate-like wall and an R ridge on the inner surface side of the plate-like wall along both of the curved portions along the width direction of the plate-like wall on both sides of the plate-like wall and at an intermediate position between the partition walls adjacent in the width direction of the plate-like wall, a ridge portion is formed by outwardly bulging the outer surface of the plate-like wall, and the plate in the partition forming portion The interval between the plate-shaped walls in the ridge portion forming portion is larger than the interval between the shaped walls, and the top portion of the R projection forming the concave groove is connected to the partition wall on the side of the flow passage, The first plate-like wall and the second plate-like wall extend along the lengthwise end of the first plate-like wall, the lengthwise end of the second plate-like wall, and the end of the short side wall connecting these ends. A crimped portion is formed by reducing the width of the plate-like wall of the above, the curved portion is formed corresponding to a part of the plurality of partition walls, and the remaining plurality of partition walls are formed to correspond to the A flat plate portion is formed that serves as part of the first plate-like wall and part of the second plate-like wall .

(3) The multi-hole flat tube of the present invention includes a first plate-like wall and a second plate-like wall that are arranged to face each other, a short side wall that connects opposite ends of the plate-like walls in the width direction, A flat multi-hole pipe made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed between the plate-like walls along the width direction of the plate-like walls, and the plate-like walls between the plate-like walls. A flat multi-hole tube having a plurality of flow paths partitioned by the partition along the length direction of the tube, wherein the partition is connected to the first plate-like wall and the second plate-like wall A curved portion is formed so as to form a concave groove on the outer surface side of the plate-like wall and an R ridge on the inner surface side of the plate-like wall along both of the curved portions along the width direction of the plate-like wall on both sides of the plate-like wall and at an intermediate position between the partition walls adjacent in the width direction of the plate-like wall, a ridge portion is formed by outwardly bulging the outer surface of the plate-like wall, and the plate in the partition forming portion The interval between the plate-shaped walls in the ridge portion forming portion is larger than the interval between the shaped walls, and the top portion of the R projection forming the concave groove is connected to the partition wall on the side of the flow passage, The first plate-like wall and the second plate-like wall extend along the lengthwise end of the first plate-like wall, the lengthwise end of the second plate-like wall, and the end of the short side wall connecting these ends. A crimped portion is formed by reducing the width of the plate-like wall of the above, and the crimped portion is curved to either one of the portions where the partition is connected to the first plate-like wall and the second plate-like wall. A flat plate portion is formed on the other side.

(4) In the flat multi-hole tube according to any one of (1) to (3) according to the present invention, both the portion where the partition is connected to the first plate-like wall and the second plate-like wall It is preferable that the curved portion is formed along the entire length of the .
(5) In the flat multi-hole tube according to (3) of the present invention, the curved portion is formed corresponding to some of the plurality of partition walls, and the curved portion is formed to correspond to the remaining plurality of partition walls. Preferably, a flat plate portion serving as a part of the first plate-like wall and a part of the second plate-like wall is formed.

(6) In the flat multi-hole pipe according to any one of (1) to (5) according to the present invention, the height difference between the bottom of the concave groove and the top of the ridge is 1 of the total height of the flat multi-hole pipe. ~5% is preferred.

INDUSTRIAL APPLICABILITY The present invention can provide a flat multi-hole pipe in which buckling and large deformation are unlikely to occur in the crimped portion even if the structure having the crimped portion is adopted.

BRIEF DESCRIPTION OF THE DRAWINGS The figure which expands and shows the cross section of the flat multi-hole pipe of 1st Embodiment which concerns on this invention. The top view which shows the edge part of the flat multi-hole pipe, and a caulking process part. The cross-sectional view which expands and shows the crimping process part. The perspective view which shows an example of the heat exchanger to which the flat multi-hole pipe is applied. The side view which shows the other example of the heat exchanger to which the flat multi-hole tube is applied. Fig. 10 is a cross-sectional view showing the arrangement relationship between the multi-hole flat pipe and the restraining jig used in the first test performed to determine the conditions for caulking the multi-hole flat pipe. The cross-sectional view which shows the flat multi-hole pipe after the said 1st test. A sixth test conducted to determine the conditions for crimping a flat multi-hole pipe and its results are shown. (B) is a cross-sectional view showing test results. A seventh test conducted to obtain the conditions for caulking a flat multi-hole pipe and its results are shown. (B) is a cross-sectional view showing test results. 8 shows an eighth test conducted to determine the conditions for crimping a flat multi-hole pipe and its results, (A) is a cross-sectional view showing the arrangement relationship between the flat multi-hole pipe and the restraining jig; (B) is a cross-sectional view showing test results.

DETAILED DESCRIPTION OF THE INVENTION A first embodiment of a multi-channel flat tube according to the present invention will be described in detail below with reference to the accompanying drawings. In addition, in the drawings used in the following explanation, in order to make the features easier to understand, the characteristic portions may be enlarged for convenience, and the dimensional ratios of each component may not necessarily be the same as the actual ones. do not have.

FIG. 1 shows an enlarged cross section of the main part of the multi-hole flat pipe 1 according to the first embodiment. 1, but as shown in the plan view of FIG. 2, a crimped portion 1A is formed only at a predetermined length portion of the end, and the crimped portion 1A is enlarged in FIG. It is said that
The structure of the main portion of the multi-hole flat tube 1 other than the crimped portion 1A is composed of a first plate-like wall 2 that is the upper surface wall and a second plate-like wall 2 that is the lower surface wall when it is horizontally arranged as shown in FIG. plate-like wall 3 and short side walls 5 connecting opposite ends of the first plate-like wall 2 and the second plate-like wall 3 to each other.
In this embodiment, the short side wall 5 is formed in a cross section <shape or cross section> shape having inclined walls 5a and 5b. but spaced substantially parallel to each other. The shape of the short side wall 5 applied in the present embodiment is an example, and the short side wall may be a projecting curved wall such as an arc or a flat short side wall.

The flat multi-hole tube 1 is made of aluminum and has a plurality of partition walls 6 intermittently formed between the plate-like walls 2 and 3 along the width direction of the plate-like walls 2 and 3 (horizontal direction in FIG. 1). Or a flat tube made of aluminum alloy. The partition walls 6 extend in a direction substantially perpendicular to the plate-like walls 2 and 3, that is, in the vertical direction in the state shown in FIG. In the example shown in the figure, 13 partition walls 6 are formed in the inner width direction of the flat multi-hole tube 1 .
Between the plate-like walls 2 and 3, a plurality of refrigerant flow passages 7 having a substantially rectangular cross section are partitioned by the partition walls 6 along the length direction of the plate-like walls 2 and 3 (the depth direction of the paper surface of FIG. 1). formed. 1 are surrounded by the partition walls 6 and the short side walls 5, so that the cross-sectional profile of the flow passages 7 is substantially pentagonal.

In the flat multi-hole tube 1, the plate-like walls 2 and 3 are not formed in a simple flat plate shape but in a plate shape including some unevenness. The plate-like walls 2 and 3 positioned above and below the two partition walls 6 closest to the short side wall 5 are flat plates, and the plate-like walls 2 and 3 above and below the partition wall 6 positioned at the center in the width direction of the flat multi-hole tube 1 3 has a flat plate shape, and curved portions 8 having an arcuate cross section are formed above and below all remaining partition walls 6 . Flat plate portions 2a and 3a are formed at the upper and lower portions of the partition wall 6 where the flat plate walls 2 and 3 are formed, respectively.
In FIG. 1, all the curved portions 8 formed on the upper side of the partition wall 6 are formed in a downward convex shape, and all the curved portions 8 formed in the lower side of the partition wall 6 are formed in an upward convex shape. there is That is, each of the curved portions 8 is formed so as to have a convex shape facing the inside of the multi-channel flat pipe 1 and a concave shape facing the outside of the multi-channel flat pipe 1 . Therefore, at the portion where the curved portion 8 is connected to the partition wall 6, the R projection 4 is formed along the entire length of the first plate-like wall 2 or the entire length of the second plate-like wall 3 on the flow path 7 side. formed. Further, at the portion where the curved portion 8 is connected to the partition wall 6, along the outer side of the first plate-like wall 2 or the outer side of the second plate-like wall 3, the entire length of the first plate-like wall 2 or the first plate-like wall 3 is extended. A concave groove 10 is formed along the entire length of the plate-like wall 3 of 2. As shown in FIG. The R projection 4 is integrally connected to the partition wall 6 at its top portion 4a.

Since the width of the curved portion 8 is formed to be the same as the width of the rectangular flow passage 7, the curved portions 8 on both sides are connected to the intermediate positions of the partition walls 6 that are adjacent to each other on the left and right in the width direction of the flat multi-hole tube 1. A ridge portion 9 is formed. The ridge portion 9 is formed so as to be positioned in the widthwise central portion of the flow passage 7, and all the ridge portions 9 formed on the first plate-like wall 2 are formed in an upwardly convex circular arc shape, and the second All of the ridges 9 formed on the plate-like wall 3 are formed in a downward convex circular arc shape. That is, each of the ridges 9 is formed in a convex shape facing the outside of the flat multi-hole tube 1 .
The vertex position of the ridge portion 9 is formed flush with the outer surface of the first plate-like wall 2 or the second plate-like wall 3 near the short side wall 5 . That is, as shown in FIG. 1, the vertex of the ridge portion 9 formed on the first plate-like wall 2 is formed at the same height as the upper surface of the first plate-like wall 2 on the short side wall side. The lowermost point of the ridge portion 9 formed on the plate-like wall 3 is formed at the same height as the lower surface of the second plate-like wall 3 on the side of the short side wall.

The flat multi-hole tube 1 shown in FIG. 1 is made of aluminum or an aluminum alloy. The thickness of the first plate-like wall 2 and the second plate-like wall 3 is about 0.15 mm, and the thickness of the partition wall is about 0.14 mm. Further, in the flat multi-hole tube 1, the depth of the downward curved portion 8 and the height of the upward curved portion 8 are approximately 0.04 to 0.06 mm. The depth of the downward curved portion 8 means the height difference between the apex height of the adjacent ridge portion 9 and the deepest position of the inner upper surface of the curved portion 8 . The height of the upward curved portion 8 means the height difference between the lowest point position of the adjacent ridge portion 9 and the highest position of the inner lower surface of the upward curved portion 8 .

As shown in FIG. 3, the crimped portion 1A in the flat multi-hole tube 1 includes a first plate-like wall 12, a second plate-like wall 13, a <shaped short side wall 15, and a > shaped short side wall 15. , and the cross-sectional shape of the main part of the multi-channeled flat tube 1 in that it is a flat tube shape having partition walls 16 . If the main portion of the flat multi-hole tube 1 has an overall width of about 18 mm as shown in FIG. 1, the overall width of the crimped portion 1A is, for example, about 17.3 mm as shown in FIGS. That is, the cross-sectional shape of the crimped portion 1A is similar to that of other portions of the flat multi-hole tube 1, but the width thereof is smaller by about 0.7 mm. In other words, as shown in FIG. 2, the lateral width of the plate-like walls 12 and 13 in the crimped portion 1A is made smaller than the width of the plate-like walls 2 and 3 in the other portions.

The crimped portion 1A differs from the main portion of the multi-hole flat tube 1 in the following points.
In the example shown in FIG. 3, as an example, in the first plate-like wall 12, counting from the left short side wall 15 side, above the third partition 16, above the fifth partition 16, and above the ninth partition Above the partition wall 16 and above the eleventh partition wall 16, the first plate-like wall 12 has curved portions 18 each having an arcuate cross-sectional shape that protrudes downward in the longitudinal direction of the plate-like wall 2. formed along. Accordingly, a plurality of grooves 19 are formed on the upper surface side of the curved portion 18 so as to extend in the longitudinal direction of the first plate-like wall 12 (the depth direction of the paper surface of FIG. 1).
Since FIG. 2 is a plan view of the plate-like walls 2 and 12, the concave groove 19 should be drawn so as to extend vertically in FIG. The description of the concave groove 19 is omitted here.

Next, in the configuration shown in FIG. 3, as an example, in the second plate-like wall 13, counted from the left short side wall 5 side, under the second partition wall 16, under the fourth partition wall 16, and 6 Under the 16th partition 16, under the 8th partition 16, under the 10th partition 16, and under the 12th partition 16, the second plate-like wall 13 is provided with an upwardly convex shape. A curved portion 20 having an arcuate cross section is formed along the length direction of the plate-like wall 3 . For this reason, a plurality of grooves 21 extending in the longitudinal direction of the second plate-like wall 13 are formed on the lower surface side of the curved portion 20 .

As shown in FIG. 3, the curved portions 18 and 20 are formed on the upper and lower sides, respectively. Curved portions 18 and 20 are alternately formed along the left-right direction of the flat multi-hole tube 1 so as to alternate vertically. Similarly, curved portions 18 and 20 are formed alternately in the right-hand side of the cross section of the crimped portion 1A so as to alternate vertically along the left-right direction of the crimped portion 1A.

Further, as shown in FIG. 3, the curved portions 18 and 20 have the same width as the flow path 17. A portion between the curved portions 18 and between the left and right curved portions 20 is formed in a flat plate shape. These flat plate-shaped portions are protruding portions compared to the concave grooves 19 and 21, and are portions that protrude continuously in the length direction of the crimped portion 1A. 22 for explanation.

In the crimped portion 1A shown in FIG. 3, on the first plate-like wall 12, the top of the first partition wall 16 and the top of the second partition wall 16 are arranged in order from the side closer to the short side wall 15 on the left side. , on the 4th partition 16, on the 6th partition 16, on the 7th partition 16, on the 8th partition 16, on the 10th partition 16, and on the 12th partition A ridge 22 is formed on the top of 16 and on the thirteenth partition 16 .
In addition, in the first plate-shaped wall 12, from the left short side wall 15, a position close to the second partition 16, a position close to the sixth partition 16, a position close to the eighth partition 16, and a position close to the 12th partition. At a position close to the partition wall 16, a small groove 23 is formed which is smaller than the previous grooves 19 and 21 and has a depth of about a fraction of the grooves 19 and 21. As shown in FIG.

In the crimped portion 1A shown in FIG. 3, in the second plate-like wall 13, the bottom of the first partition 16 and the bottom of the third partition 16 are arranged in order from the side near the short side wall 5 on the left. , under the fifth bulkhead 16, under the seventh bulkhead 16, under the ninth bulkhead 16, under the eleventh bulkhead 16, and under the thirteenth bulkhead 16. It is

Further, in the flat multi-hole tube 1, the concave grooves 21 are deep grooves with a depth of about 0.090 to 0.094 mm, and the small grooves 23 are shallow grooves with a depth of about 0.023 to 0.026 mm.

In the crimped portion 1A, although the first plate-like wall 12 and the second plate-like wall 13 have some unevenness, they are arranged substantially parallel to each other, and the partition wall 16 is arranged orthogonally to them. The shape of the main part of the flat multi-hole tube 1 is the same as that of the short side wall 15 formed in a > shape.
In addition, the height (thickness) of the crimped portion 1A is about 2 mm, the height of the partition wall is about 1.7 mm, the thickness of the first plate-like wall 12 and the second plate-like wall 13 is about 0.15 mm, the partition wall 16 The structure is the same as that of the main portion of the flat multi-hole tube 1 in that it is formed to have a thickness of about 0.14 mm.

As shown in the plan view of FIG. 2, crimped portions 1A are formed at the longitudinal ends of the flat multi-hole pipe 1 by crimping so as to narrow the left and right widths of the flat multi-hole pipe 1 in the width direction. there is The crimped portion 1A is formed by pressing a crimping jig as indicated by arrows _B1 and B2 in _FIG .
The crimping jig used here is a crimping jig having <type or >type recesses, and a crimping jig having <type recesses on the side is arranged on the left side of FIG. A caulking jig having a concave portion of the mold is arranged on the right side of _FIG . ₁ , and caulking can be performed by narrowing the gap between these left and right caulking jigs in the directions of arrows B1 and B2 in FIG.

If the flat multi-hole pipe 1 having the configuration shown in FIGS. 1 to 3 has the crimped portion 1A at the end portion, the buckling portion at the crimped portion 1A as shown in the cross section of FIG. There is no large deformed part.
Therefore, even when the crimped portion 1A is inserted into a slit hole of a heat exchanger header tube or the like, which will be described later, and brazing is performed, brazing can be performed without causing defective brazing.

In addition, when applying the above-mentioned structure to the flat multi-hole pipe 1, it is desirable to apply it to a flat multi-hole pipe having a small width and a thin thickness. The size of the flat multi-hole tube suitable for application is about 14 mm to 100 mm in height, about 0.15 mm to 0.6 mm in thickness of the first plate-like wall and the second plate-like wall, and about 0.15 mm to 0.6 mm in thickness of the partition wall. A flat multi-hole tube with a thickness of about 0.14 mm to 0.6 mm can be exemplified.

FIG. 4 is a perspective view showing an example of a heat exchanger provided with a flat multi-hole tube 1 having crimped portions 1A at both ends.
The heat exchanger 11 of this example is used as a heat exchanger for an outdoor unit of a room air conditioner or a package air conditioner, an outdoor unit for HVAC (Heating Ventilating Air Conditioning), a heat exchanger for automobiles, and the like. It is an all-aluminum heat exchanger that

The heat exchanger 11 includes a pair of header tubes 24 spaced apart from each other and arranged parallel to each other, and a pair of header tubes 24 arranged parallel to each other with a space therebetween and substantially perpendicular to the header tubes 24. A plurality of joined flat multi-hole tubes 1 and a plurality of fins 23 brazed to the upper and lower surfaces of the flat multi-hole tubes 1 for dissipating heat to the outside air are provided.
One of the pair of header pipes 24 is provided with a supply pipe 25 for supplying refrigerant to the flat multi-hole pipe 1 via the header pipe 24 . The other header pipe 24 is provided with a recovery pipe 26 for recovering the refrigerant that has passed through the flat multi-hole pipe 1 . The multi-hole flat tube 1, fins 23, header tube 24, supply tube 25 and recovery tube 26 are made of aluminum or an aluminum alloy.

The fins 23 are formed with a plurality (eight in the present embodiment) of notches 29 corresponding to the outer peripheral shape of the flat multi-hole tube 1 . The multi-channel flat tubes 1 are fitted into the cutouts 29 and fixed by brazing.

A plurality of fins 23 are arranged in parallel, and the flat multi-hole pipe 1 is inserted through each notch 29 . The plurality of fins 23 are arranged parallel to each other at regular intervals. The fin 23 has a bent portion 28 bent along the outer surface of the multi-channeled flat tube 1 on the periphery of the notch portion 29 . The bent portion 28 can be formed by, for example, burring.

The flat multi-hole pipe 1 and the fins 23 are connected by fitting the flat multi-hole pipe 1 into the cutouts 29 of the fins 23 so as to skewer the fins 23 arranged at regular intervals and brazing the connecting portions. Fixed. A slit-like insertion hole is formed in the portion of the header pipe 24 where each flat multi-hole pipe 1 is connected, and the crimped portion 1A of the flat multi-hole pipe 1 is inserted through this insertion hole. The flat multi-hole pipe 1 is joined to the header pipe 24 by brazing the inserted portion to the header pipe 24 .
The fins 23 of this example have the cutouts 29 through which the multi-hole flat tubes 1 are inserted. may be inserted and brazed.

The flat multi-hole pipe 1 is joined by inserting the caulked portion 1A at the end into the slit-shaped insertion hole of the header pipe 24 and brazing, so that the refrigerant does not flow between the header pipe 24 and the flat multi-hole pipe 1. can flow in and out. Since the crimped portion 1A of the multi-hole flat tube 1 does not have a large deformed portion or unevenness, it can be inserted into the insertion hole of the header tube 24 without gaps and can be brazed. Therefore, the heat exchanger 11 shown in FIG. 4 can be joined without causing a defective brazing portion such as a gap in the brazed portion between the header pipe 24 and the flat multi-hole pipe 1 .

FIG. 5 is a perspective view showing another example of a heat exchanger provided with a flat multi-hole tube 1 having crimped portions 1A at both ends.
The heat exchanger 30 includes header pipes 31 and 32 that are spaced apart from each other in the left and right direction and arranged parallel to each other. It is mainly composed of a plurality of flat multi-hole pipes 1 joined perpendicularly to each other and corrugated fins 34 attached to each flat multi-hole pipe 1 . The header pipes 31, 32, the flat multi-hole tube 1 and the fins 34 are made of aluminum or aluminum alloy.

More specifically, a plurality of slit-shaped insertion holes are formed in the opposing side surfaces of the header pipes 31 and 32 at regular intervals in the longitudinal direction of each pipe. The flat multi-hole pipe 1 is installed between the header pipes 31 and 32 by inserting the crimped portion 1A of the flat multi-hole pipe 1. As shown in FIG. The crimped portion 1A of the flat multi-hole tube 1 is brazed to the header pipes 31 and 32. As shown in FIG. Further, fins 34 are arranged between a plurality of flat multi-hole pipes 1, 1 that are installed between the header pipes 31, 32 at predetermined intervals, and these fins 34 are arranged on the front surface side or the rear surface side of the flat multi-hole pipe 1. brazed.

In the heat exchanger 30 as well, the refrigerant can flow in and out between the header pipes 31 and 32 and the flat multi-hole tube 1 in the same manner as in the heat exchanger 11 described above. Since the crimped portion 1A of the flat multi-hole tube 1 does not have a large deformed portion or irregularities, it can be inserted into the insertion holes of the header pipes 31 and 32 without gaps. Therefore, the heat exchanger 30 shown in FIG. 5 can be joined without causing defective brazing such as gaps in the brazed portions between the header pipes 31 and 32 and the flat multi-hole tube 1 .

EXAMPLES The present invention will be described in more detail below with reference to Examples, but the present invention is not limited to these Examples.
A first simulation analysis ( No. 1 test) was performed.
Non-linear software for structural analysis (LS-DYNAv.971: product name manufactured by JSOL Co., Ltd.) is used as the solver, the dynamic explicit method is used, a two-dimensional model is adopted as the model type, the model material is set to JIS 3003 alloy, and the material Set the material constitutive formula of the model to elasto-plastic (plastic isotropy), select the rigid body as the material model of the tool, select the complete integral S/R solid element as the element type, and the average element size is 0.02 mm. , and a coefficient of friction of 0.1, the simulation conditions shown in Table 1 below were set.

As shown in the cross section of FIG. 6, it has a flat plate-like first plate-like wall 51 and a second plate-like wall 52 that do not have unevenness, and has a total width of 18 mm, a height of 2 mm, and a partition wall 53 with a height of 2 mm. 1.7 mm, the wall thickness of the partition wall 53 is 0.14 mm, the number of the partition walls 53 is 13, the surface interval between the partition walls 53 adjacent to each other on the left and right is 1.06 mm, and the interval including the thickness of the partition walls 53 on the left and right is 1. 34 mm, the wall thickness of the first plate-like wall 51 and the second plate-like wall 52 is 0.15 mm, and the flat multi-hole tube 55 for test has short side walls 54 of > and < shapes. FIG. 6 shows only the right half of the cross section of this test multi-hole tube 55 . The angle at which the slopes of the short side walls 54 intersect with each other is 90°, and the thickness of the short side walls 54 is set to a minimum thickness of 0.23 mm and a maximum thickness of 1 mm.

With respect to the flat multi-hole tube 55 of this cross-sectional shape, the upper constraining plate 40 and the lower constraining plate 41 made of a rigid body are arranged at a portion of 7 mm left and right from the central portion in the width direction, and a total width of 14 mm on the left and right. , The flat multi-hole pipe 55 is held down by fixing the position in the space without gaps with the flat multi-hole pipe 55, and the width is reduced from both the left and right sides of this test flat multi-hole pipe with a caulking jig. A first simulation analysis (test of No. 1) of caulking that applies pressure in the direction was performed. The amount of caulking was 0.35 mm on one side and 0.7 mm in the entire width direction of the flat multi-hole tube 55 .

The crimping jig has a concave shape that matches the shape > or < of the short side wall 54, and the crimping force does not act to crush the tip of the short side wall 54, but rather It was made to act so as to shrink the whole.

As a result of the first simulation analysis, as shown in FIG. 7, the stress was concentrated around the rectangular cross-sectional flow path closest to the short side wall on the right end. As a result, the first plate-like wall 51 and the second plate-like wall 52 located between the first and second partition walls from the short side wall on the right side curved greatly inward of the flow path and buckled. . The first plate-like wall portion and the second plate-like wall portion near the ends of the constraining plates 40 and 41 were greatly deformed with respect to the flat multi-hole tube 55 whose upper and lower sides were pressed by the constraining plates 40 and 41 . The distance between the first plate-like wall and the second plate-like wall, which are convexly curved toward the inside of the flow passage and where the amount of deformation is greatest is 1.125 mm. and the second plate-like wall bulged outward with a maximum distance of 2.08 mm. In this case, the maximum amount of buckling including the thickness of the first plate-like wall 51 can be estimated to be 0.44 mm.
Tables 1 and 2 below summarize the conditions and results of the first simulation (test No. 1) before and after caulking. The simulation analyzes of No. 2 to No. 4 (second test to fourth test) were performed below, and Tables 1 and 2 summarize those conditions. The details of the simulation analyzes of No. 2 to No. 4 will be described later.
In addition, in the column of buckling concentration determination shown in Table 2, when the amount of buckling is more than 20% of the height before crimping (flat pipe total height), x is when it is more than 10%, and 5 to 10% is when it is more than 10%. The case of ∘ is indicated, and the case of 5% or less is indicated by ⊚.

"Second simulation analysis (No. 2 test)"
In order to investigate the cross-sectional relationship between the upper constraining plate and the flat multi-hole pipe by crimping, as shown in FIG. A condition was set in which a ridge 49 extending in the direction was formed and a gap of 0.05 mm was provided between the lower surface of the restraining plate 48 on the upper side and the upper surface of the flat multi-hole tube.

Regarding the cross-sectional shape of the flat multi-hole pipe, a shape having a first plate-like wall 61, a second plate-like wall 62, a partition wall 63, and a short side wall 64 shown in FIG. 8(A) was set. Furthermore, in the first plate-like wall 61 and the second plate-like wall 62 , there is an inwardly convex groove 65 between the laterally adjacent partition walls, and ridges 66 are provided on the upper and lower portions of the partition wall 63 . and the depth of the groove 65 was set to 0.02 to 0.35 mm. The thickness of each plate-like wall, partition wall and short side wall is the same as in the previous example.
Under these conditions, a second simulation analysis (test No. 2) was performed in which a crimping force was applied under crimping conditions equivalent to those described above.

The results are shown in FIG. 8B and Table 2. Deformation was concentrated on the center side of the upper constraining plate 48 in the width direction and the center side of the lower constraining plate 41 in the width direction. The first plate-like wall on the right one side from the center of the restraining plate 48 on the upper side was buckled and deformed into a downward convex shape. In addition, the second plate-like wall 62 in the center portion in the width direction of the restraint plate 41 on the lower side was buckled and deformed in an upward convex shape. The buckling amount on the first plate-like wall side is 0.314 mm, the buckling amount on the second plate-like wall side is 0.287 mm, and the maximum buckling amount in this example can be estimated at 0.37 mm. rice field.
Although FIG. 8B shows only the buckling amount of 0.314 mm, the buckling amount of the portion indicated as 1.68 mm on the left side of this buckling portion is (height 2.0 mm + Since the gap is 0.37 mm from the calculation formula of 0.05 mm)-1.68 mm, this portion is the position where the maximum buckling occurs.

"Third simulation analysis (No. 3 test)"
In order to examine the relationship between the cross-sectional shape of the constraining plate on the upper side and the multi-hole flat pipe by caulking, as shown in FIG. A condition was set such that a ridge 49 extending in the vertical direction was formed and a gap of 0.05 mm was provided between the lower surface of the restraining plate 48 and the upper surface of the flat multi-hole tube.

Regarding the cross-sectional shape of the flat multi-hole pipe, as shown in FIG. set. Further, the first plate-like wall 71 and the second plate-like wall 72 have grooves 75 in the upper and lower portions of the partitions 73, and protrusions 76 projecting outward between the partitions adjacent to the left and right. A flat multi-hole tube 70 was set in which the shape was set and the depth of the concave groove 75 was set to 0.05 mm. The thickness of each plate-like wall, partition wall and short side wall is the same as in the previous example.
Under these conditions, a third simulation analysis (test No. 3) was performed in which a crimping force was applied under crimping conditions equivalent to those described above.

The results are shown in FIG. 9(B) and Table 2. A tendency for the deformed portions due to the caulking process to disperse was observed. In the first plate-like wall 71, buckling occurs in the upper part of every other partition wall adjacent to the left and right, and in the second plate-like wall 72, buckling occurs in the upper part of the upper part of the partition wall adjacent to the left and right. There has occurred. The amount of buckling on the side of the first plate-like wall is 0.142 mm, and the amount of buckling on the side of the second plate-like wall is 0.142 mm. Distributed on every other septum. This result is the result of achieving the purpose of reducing buckling and distributing deformation.
From these test results, if the structure shown in FIG. 9A is adopted, the maximum amount of buckling can be estimated to be 0.2 mm. rice field.
With the maximum amount of buckling as described above, even if the end of the multi-hole flat tube is inserted into the slit-shaped connecting hole of the header tube 14 and brazed, the amount of deformation does not lead to poor brazing. can be regarded as
Although FIG. 9(B) only shows the buckling amount of 0.142 mm, the buckling portion indicated as 1.85 mm is (height 2.0 mm+gap 0.05 mm)−1. From the formula for 85 mm, the maximum amount of buckling can be estimated at 0.2 mm.

"Fourth simulation analysis (No. 4 test)"
Next, using the upper constraining plate 40 and the lower constraining plate 41 equivalent to those in the first test shown in FIG. The restraining plate 41 on the lower side is arranged above and below the multi-hole flat tube 70, the end of the restraining plate 40 on the upper side and the end of the restraining plate 41 on the lower side are installed in front of the partition wall 73 on the right end, and the concave The depth of groove 75 was set to 0.05 mm. The thickness of each plate-like wall, partition wall and short side wall is the same as in the previous example.
A fourth simulation analysis (test No. 4) was performed in which a crimping force was applied under crimping conditions equivalent to those described above.

The results are shown in FIG. 10B and Table 2. The amount of buckling due to the caulking process is greatly reduced, and among the adjacent partition walls 73, on the first plate-like wall side, every other partition wall 73 small deformation occurred. Further, among the adjacent partition walls 73, on the second plate-like wall side, a small deformation occurred at a position away from the first plate-like wall side with respect to every other partition wall 73. As shown in FIG. The amount of deformation on the side of the first plate-like wall was 0.093 mm or 0.094 mm, which was a sufficiently small amount of deformation.

The deformation amounts on the second plate-like wall side were 0.090 mm, 0.093 mm, and 0.091 mm, which were sufficiently small deformation amounts. In addition, fine deformation of 0.023 mm or 0.026 mm occurred at positions deviated from these deformation positions.
In FIG. 10, the maximum amount of buckling (maximum amount of deformation) could be estimated to be 0.097 mm from the formula for the height of 2.0 mm-1.903 mm.

If the amount of deformation is at the level described above, even if the end portion of the multi-hole flat tube is inserted into the slit-shaped connection hole of the header tube 14 and brazed, the amount of deformation will not lead to defective brazing. can be regarded as
For this reason, in the crimped portion 1A, grooves 75 are formed in the plate-like walls 71 and 72 along the entire length of the portion where the partition wall 73 is connected to the first plate-like wall 71 and the second plate-like wall 72. Between the plurality of grooves 75 adjacent in the width direction of the plate-like walls 71 and 72, a ridge portion 76 is formed by bulging the outer surface of the plate-like wall outward to form a ridge portion 76 between the plate-like walls in the partition forming portion. Based on the spacing, it is presumed that if the spacing between the plate-like walls at the portion where the ridge portion 76 is formed is increased, the amount of deformation due to caulking is reduced. Therefore, the shape of the crimped portion 1A is preferably the shape described above.

From the results shown in FIGS. 10(A) and 10(B), when the flat multi-hole pipe 70 having the cross-sectional shape shown in FIG. 10(A) is applied, the amount of deformation is small even after caulking. It can be seen that the cross-sectional shape shown in (B) is obtained.

Therefore, in the case of constructing a flat multi-hole pipe having the crimped portion 1A at the end, if the cross-sectional shape of the main portion excluding the crimped portion 1A is the cross-sectional shape shown in FIG. The cross-sectional shape of is shown in FIG. 10B, which is an allowable shape.
If the flat multi-hole tube of this structure is applied to the heat exchangers 11 and 30 of the brazed structure shown in FIGS. A brazed portion between the multi-hole pipe 1 and the header pipe 32 can be joined with no brazing defects.

Further, with the cross-sectional shape shown in FIG. 10(A), it is possible to provide a flat multi-hole pipe in which the crimped portion 1A does not undergo buckling or large deformation even if it is crimped after extrusion. In addition, when the crimped portion 1A is cut to obtain a flat multi-hole pipe having a required length, a flat multi-hole pipe having a well-shaped crimped portion 1A can be provided.

DESCRIPTION OF SYMBOLS 1... Flat multi-hole pipe, 1A... Crimping process part, 2... 1st plate-shaped wall, 3... 2nd plate-shaped wall, 4... R protrusion, 4a... Top part, 5... Short side wall, 6... Partition wall, 7 Flow passage 8 Curved portion 9 Ridge 11 Heat exchanger 12 First plate wall 13 Second plate wall 15 Short side wall 16 Partition wall 18 20... Curved portion 19... Concave groove 21... Concave groove 22... Ridge portion 23... Small groove 24... Header pipe 25... Supply pipe 26... Recovery pipe 23... Fin 24... Header pipe 25... Supply pipe 29 Recovery pipe 30 Heat exchanger 31, 32 Header pipe 34 Fin 70 Multi-hole flat tube 71 First plate wall 72 Second plate wall 73... Partition wall, 75... Concave groove, 76... Ridge part.

Claims (6)

A first plate-like wall and a second plate-like wall arranged to face each other, a short side wall connecting opposite ends of the plate-like walls in the width direction, and a width of these plate-like walls between the plate-like walls A flat multi-hole tube made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed along the direction, and partitioned by the partition walls along the length direction of the plate-like walls between the plate-like walls A flat multi-hole pipe in which a plurality of flow paths are formed,
A concave groove is formed on the outer surface side of the plate-like wall so as to extend along both the portions where the partition is connected to the first plate-like wall and the second plate-like wall. A curved portion forming a line is formed,
Ridges that protrude outward from the outer surface of the plate-like wall at intermediate positions between the partition walls that are adjacent to each other in the width direction of the plate-like wall on both sides of the curved portion along the width direction of the plate-like wall. the interval between the plate-like walls in the ridge portion-forming portion is larger than the interval between the plate-like walls in the partition-forming portion, and the top portion of the R ridges forming the recessed groove is located in the flow path. connected to the bulkhead at the roadside ;
Of the plurality of partition walls, the curved portion is formed to correspond to a portion of the partition walls, and a portion of the first plate-like wall and the second plate-like wall are formed to correspond to the remaining plurality of partition walls. A flat multi-hole pipe characterized in that a flat plate portion that also serves as a part of is formed . A first plate-like wall and a second plate-like wall arranged to face each other, a short side wall connecting opposite ends of the plate-like walls in the width direction, and a width of these plate-like walls between the plate-like walls A flat multi-hole tube made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed along the direction, and partitioned by the partition walls along the length direction of the plate-like walls between the plate-like walls A flat multi-hole pipe in which a plurality of flow paths are formed,
A concave groove is formed on the outer surface side of the plate-like wall so as to extend along both the portions where the partition is connected to the first plate-like wall and the second plate-like wall. A curved portion forming a line is formed,
Ridges that protrude outward from the outer surface of the plate-like wall at intermediate positions between the partition walls that are adjacent to each other in the width direction of the plate-like wall on both sides of the curved portion along the width direction of the plate-like wall. the interval between the plate-like walls in the ridge portion-forming portion is larger than the interval between the plate-like walls in the partition-forming portion, and the top portion of the R ridges forming the recessed groove is located in the flow path. connected to the bulkhead on the roadside,
The first plate-like wall and the lengthwise end of the second plate-like wall are connected to the ends of the short side walls connecting these ends. A crimped portion is formed by reducing the width of the second plate-like wall ,
Of the plurality of partition walls, the curved portion is formed to correspond to a portion of the partition walls, and a portion of the first plate-like wall and the second plate-like wall are formed to correspond to the remaining plurality of partition walls. A flat multi-hole pipe characterized in that a flat plate portion that also serves as a part of is formed . A first plate-like wall and a second plate-like wall arranged to face each other, a short side wall connecting opposite ends of the plate-like walls in the width direction, and a width of these plate-like walls between the plate-like walls A flat multi-hole tube made of aluminum or an aluminum alloy and provided with a plurality of partition walls intermittently formed along the direction, and partitioned by the partition walls along the length direction of the plate-like walls between the plate-like walls A flat multi-hole pipe in which a plurality of flow paths are formed,
A concave groove is formed on the outer surface side of the plate-like wall so as to extend along both the portions where the partition is connected to the first plate-like wall and the second plate-like wall. A curved portion forming a line is formed,
Ridges that protrude outward from the outer surface of the plate-like wall at intermediate positions between the partition walls that are adjacent to each other in the width direction of the plate-like wall on both sides of the curved portion along the width direction of the plate-like wall. the interval between the plate-like walls in the ridge portion-forming portion is larger than the interval between the plate-like walls in the partition-forming portion, and the top portion of the R ridges forming the recessed groove is located in the flow path. connected to the bulkhead on the roadside,
The first plate-like wall and the lengthwise end of the second plate-like wall are connected to the ends of the short side walls connecting these ends. A crimped portion is formed by reducing the width of the second plate-like wall,
In the caulking portion, a curved portion is formed on one of the portions where the partition wall is connected to the first plate-like wall and the second plate-like wall, and a flat plate portion is formed on the other. Flat multi - hole pipe. Claims 1 to 3 , characterized in that the curved portion is formed along the entire length of both the portions where the partition is connected to the first plate-like wall and the second plate-like wall. Flat multi-hole pipe according to any one of . Of the plurality of partition walls, the curved portion is formed to correspond to a portion of the partition walls, and a portion of the first plate-like wall and the second plate-like wall are formed to correspond to the remaining plurality of partition walls. 4. The flat multi-hole pipe according to claim 3, wherein a flat plate part serving as a part of is formed. The flat tube according to any one of claims 1 to 5 , wherein the height difference between the bottom of the concave groove and the top of the ridge is 1 to 5% of the total height of the flat multi-hole tube. multi-hole tube.

Images