JP5706665B2 - Reinforcement structure of heat exchanger - Google Patents

Description

  The present invention mainly relates to a reinforcing structure of a heat exchanger (radiator) for cooling engine coolant of an automobile.

The heat exchanger for cooling the engine coolant has a temperature difference between a large number of tubes arranged in parallel, especially in the four corner tubes of the heat exchanger, between the rigid support material, the front row tube and the last row tube. In this case, large thermal distortion occurs. According to the experiment, particularly, the tube cracks at the front end of the front row tube and the rear end of the rear row tube (semicircular arc surface) near the tube insertion hole of the header plate and the brazed portion of the tube. .
In particular, when the engine is started under the condition that the outside air temperature is minus 40 degrees as an example, such as in a cold district, the thermostud valve opens and hot water of about 50 to 80 degrees flows rapidly into the heat exchanger tube. Large heat distortion occurs between the tubes. That is, a large thermal distortion occurs transiently when the engine is started.

  As a reinforcing structure of a heat exchanger that solves such a problem, each invention described in the following patent documents is known. In the former, reinforcing members formed in a U-shaped cross section are arranged at both ends of the long tube side of the cross section of the flat tube. The latter has a pair of flat legs, and both the legs are inserted into both ends of the long tube side of the cross section of the flat tube.

EP 1562015 A2 JP 2007-163124 A

Any of the above-mentioned known documents is applied to a single-row heat exchanger in which flat tubes are arranged in a row, and a pair of insertion portions of reinforcing members are inserted on both sides of the long axis of the cross section of each tube. There is a disadvantage that the inlet opening of the flat tube is largely blocked at two places.
Further, according to the experiment by the present inventor, in the two-row heat exchanger, it is clear that cracks are generated in the front arcuate portion of the flat tube in the front row and the rear arcuate portion in the rear row. Therefore, it is necessary to reinforce that part intensively. In the case of three or more rows, the same problem occurs in the flat tubes in the front row and the last row.
Therefore, the present invention has been created based on such knowledge.

In the first aspect of the present invention, a large number of flat tubes (1) and fins (2) arranged in a line are inserted through both ends of each flat tube (1), and the insertion portions are brazed. In the reinforcing structure of the heat exchanger comprising a pair of header plates (4),
The flat tube (1) includes a pair of opposed parallel plane portions (1a) and a pair of semicircular arc-shaped inner surface portions (1b) respectively connecting both edges of each plane portion (1a). And
A reinforcing member (5) made of a bent body of a metal plate having a plate thickness w that matches 1/2 of the distance S between the opposed flat portions (1a) of the opening of the flat tube (1),
The reinforcing member (5) is formed with a flat L-shaped portion (7) in an unfolded state at both ends in the longitudinal direction of the elongated connecting portion (6), and both end portions of the L-shaped portion (7) are , superimposed folded back to the connecting portion (6) side and a semi-circular curved surface outer periphery of the cross section of the folding edges is aligned with the semicircular inner surface of the flat tube (1) the (1b) ( 5a) has a superposed part (8), and the superposed part (8) fills half of the long axis of the flat tube bent in an L-shaped cross section perpendicular to the plane of the connecting part (6). Has two inserts (9) of width not
The two insertion portions (9) of the reinforcing member (5) are inserted into the openings of the flat tubes (1) in only the outermost rows in the parallel direction of the flat tubes, and the semicircular curved surfaces (5a ) outer peripheral gap contacts without and the semi-circular inner surface portion (1b) of the flat tubes (1b) of, is fitted on only both ends of the long axis direction of the opening of the flat tube (1), the fitting portion It is the reinforcement structure of the heat exchanger characterized by being brazed.

In the present invention according to claim 2, a large number of flat tubes (1) and fins (2) arranged in a plurality of rows are inserted into both ends of each flat tube (1), and the insertion portions are brazed. in the reinforcing structure of the heat exchanger comprising a pair of header plate (4),
The flat tube (1) includes a pair of opposed parallel plane portions (1a) and a pair of semicircular arc-shaped inner surface portions (1b) respectively connecting both edges of each plane portion (1a). And
A reinforcing member (5) made of a bent body of a metal plate having a plate thickness w that matches 1/2 of the distance S between the opposed flat portions (1a) of the opening of the flat tube (1),
The reinforcing member (5) has a U-shaped flat portion (7a) formed outwardly at its both ends in the longitudinal direction of the elongated connecting portion (6) in an unfolded state, and the U-shaped portion ( Both end portions of 7a) are folded and overlapped to the connecting portion (6) side, and the outer periphery of the cross-section of the folded end edge is aligned with the semicircular arc-shaped inner surface portion (1b) of the flat tube (1). The flat tube has a superposed portion (8) to be a semicircular curved surface (5a), and the superposed portion (8) is bent in a cross-sectional L shape perpendicular to the plane of the connecting portion (6). Has four inserts (9) with a width less than half of the long axis of
Each of the four insertion portions (9) of the reinforcing member (5) is inserted into the opening of a pair of adjacent flat tubes (1) in the front row and the last row at the corner of the heat exchanger core. semi-circular inner surface (1b) in the gap contact without and and the outer periphery flat tube semicircular curved surface (5a) (1b), the forwardmost portion of the long axis direction of the opening of their flat tube (1) and The reinforcing structure of the heat exchanger is characterized in that it is fitted only at the rearmost end portion and the fitting portion is brazed.

According to a third aspect of the present invention, in the reinforcing structure for a heat exchanger according to the first or second aspect,
It is a reinforcing structure of a heat exchanger in which the leading edge of each insertion portion (7) of the reinforcing member (5) is formed on a tapered surface (17).
According to a fourth aspect of the present invention, in the reinforcing structure for a heat exchanger according to any one of the first to third aspects,
At the center of the plane of the heat exchanger core, one header plate (4) is provided with a two-pass partition (11), and the above-mentioned reinforcement is applied to the flat tubes (1) on both sides adjacent to the partition (11). The reinforcing structure of the heat exchanger is brazed to the member (5).

The reinforcing member 5 of the reinforcing structure according to claims 1 and 2 of the present invention is inserted only in the foremost part and the last part of each flat tube 1 in the foremost line and the last line only, and the insertion part 9 is brazed. It is attached. Therefore, it is possible to effectively reinforce a portion where cracks are likely to occur. At the same time, the obstruction of the opening of the flat tube can be minimized.
Since the outer circumference of the semicircular curved surface 5a of the insertion portion 9 is aligned and in contact without any gap in the semi-circular inner surface 1b of the flat tube 1, to improve the brazing strength between the flat tube 1 inner surface. And the brazing structure of the reliable reinforcement member 5 is provided, and it can become a heat exchanger strong against a heat distortion.

In the above configuration, when the tip portion is formed on the tapered surface 17 as described in claim 3, it is easy to insert the insertion portion 9 of the reinforcing member 5 into the opening of the flat tube 1, and the brazing is further strengthened. Can be.
In the above configuration, in the case where the two-pass partition 11 is provided as described in claim 4, since the reinforcing members 5 are brazed to the flat tubes 1 on both sides adjacent to the two-pass partition 11, particularly in the vicinity of the partition 11. The thermal stress concentrated on the flat tube 1 can be effectively supported and the reinforcing effect can be enhanced.

It is explanatory drawing which shows the manufacturing process of the reinforcement member 5 of this invention in order with (A)-(C), (D) is DD sectional drawing of the (C). Explanatory drawing which attaches the reinforcement member 5 to the heat exchanger core 3. FIG. The top view which shows the same attachment state. IV-IV arrow sectional drawing of FIG. The perspective explanatory drawing of the arrangement position of the reinforcing member 5 in the heat exchanger core 3 having the partition 11. Explanatory drawing which shows the manufacturing process of the other reinforcement member 5 of this invention in order. The principal part top view of the heat exchanger core which has the same reinforcement member. VIII-VIII arrow sectional drawing of FIG. Explanatory drawing which shows in order the manufacturing process of the other reinforcement member 5 of this invention. The top view which shows the same attachment state. The cross section of the other flat tube to which the reinforcement structure of this invention is applied.

Next, embodiments of the present invention will be described with reference to the drawings.
The present invention relates to a heat exchanger for cooling engine cooling water, which is generally referred to as an automobile radiator, and more particularly to a reinforcing structure in which flat tubes are arranged in two or more rows. FIG. 2 is a perspective view of an essential part of the heat exchanger, in which a large number of flat tubes 1 and fins 2 arranged in parallel in two rows are alternately arranged, and both ends of each flat tube 1 have a pair of header plates 4 (see FIG. 5). A large number of tube insertion holes are formed in the header plate 4 in advance, and the edge of the hole is subjected to burring on the inner surface side.

As shown in FIG. 3, the flat tube 1 has a major axis and a minor axis in its opening, and the minor axis length S of the opening (distance between the opposing flat portions 1a) is 1.6 mm in this example. Yes, the long axis of the opening is 12mm. In other words, the flat tube 1 includes a pair of opposed parallel plane portions 1a and a pair of semicircular arc-shaped inner surface portions (1b) respectively connecting both edges of the plane portions 1a.
Support members 19 are disposed at both ends of the flat tube and the fin in the parallel direction, and both ends of the support member 19 are fixed to the header plate 4.

In such a two-row heat exchanger, reinforcing members 5 are attached to the four corners of the heat exchanger core 3, respectively. As shown in FIGS. 1 and 2, the reinforcing member 5 is formed of a bent body of a metal plate having a thickness w that matches the half of the short axis length S of the opening of the flat tube 1.
As shown in FIG. 1 (A), the reinforcing member 5 has a pair of planar U-shaped portions 7a formed at both ends in the longitudinal direction of the elongated connecting portion 6 in an unfolded state with the opening side facing outward. And as shown to (B), both the front-end | tip parts of each U-shaped part 7a are return | folded and overlapped with the connection part 6 side by the valley fold line 8a. Then, the folded end edge is formed in a semicircular arc shape with the plate thickness w as the curvature radius, and the curved surface 5a is formed there.

The curved surface 5a is aligned with the semicircular arc inner surface portion 1b of the flat tube 1. The folded overlapped portion 8 is bent into a L-shaped cross section perpendicular to the plane of the connecting portion 6 as shown in (C). As a result, they form four inserts 9 that are less than half the long axis of the flat tube.
The valley fold line 8a of the planar U-shaped portion 7a in FIG. 1A is located outside the end edge 6a of the connecting portion 6, and the curved surface 5a is disposed outside the end edge 6a for insertion. When the portion 9 is inserted into the edge on the long axis side of the opening of the flat tube 1, the contact state between the curved surface 5a and the semicircular arc-shaped inner surface 1b of the flat tube 1 and its brazing state can be easily confirmed. ing.

Thus, the plate thickness w of the reinforcing member 5 is matched to ½ of the short axis length S of the opening of the flat tube 1. In this example, the plate thickness w of the reinforcing member 5 is 0.8 mm. The thickness of the insertion portion 9 is 1.6 mm, the width is 5 mm, and the total length in the direction of the connecting portion 6 is 34.6 mm. And the dimension between the outer surfaces of a pair of opposing insertion part 9 can be 9.8 mm as an example. Each of these dimensions is shown in FIG. 2, when fitted into the openings of the four flat tubes 1 adjacent to each other at the corners of the core, as shown in FIG. 3, each insertion portion 9 has a front end portion of the front row tube and a rear row tube. It is set as the dimension fitted to the rear-end part.
As shown in FIG. 5, the cross section of each insertion portion 9 is aligned with the curved surface 5 a at the edge in the width direction on the semicircular arc inner surface portion 1 b on the inner surface of the end portion on the long axis side of the flat tube 1.

  In the heat exchanger of this example, as shown in FIG. 5, the partition 11 is arranged in one tank body 12, and the cooling water 22 circulates in two passes. For this purpose, the reinforcing members 5 are arranged at positions on both sides adjacent to the upper and lower ends and the partition 11 in the figure.

The heat exchanger core 3 assembled in this manner is such that a brazing material is coated or disposed on at least one side of each component that contacts each other, and the whole is inserted into a high-temperature furnace to be integrally brazed and fixed. is there. At this time, as shown in FIGS. 3 and 4, a wax fillet 25 is formed on the outer periphery of the insertion portion 9 of the reinforcing member 5 as shown in FIGS. Then, the whole is integrally brazed and fixed.
In this example, the small flange portion 21 of the resin tank body 12 is fitted into the annular groove 24 of the header plate 4 via an O-ring (not shown), and the caulking claw portion 20 is caulked to thereby fix the heat exchanger. Complete.

  Then, as shown in FIG. 5, high-temperature cooling water 22 flows from one inlet pipe 13, flows from right to left in each flat tube 1 positioned above the partition 11, and the other tank body 12 is connected to the U The tank body 12 is separated from the header plate 4 for convenience of explanation in FIG. The U-turned fluid flows through the flat tube 1 from the left to the right, and flows out from the other outlet pipe 14. And the airflow by a fan or a driving | running | working wind distribute | circulates on the outer surface of the flat tube 1 and the fin 2, and heat exchange is performed between the cooling water 22 and an airflow.

At this time, in FIGS. 2 to 5, the insertion portions 9 of the reinforcing member 5 are integrally brazed and fixed to the flat tubes 1 at least at the four corners, and the opening of the flat tube 1 is reduced accordingly. .
In addition, the dimension of each part in the said Example can be changed in design as needed.
Next, FIGS. 6 to 8 show other examples of the reinforcing structure of the present invention. The difference from the first embodiment is the bending direction of the U-shaped portion 7a of the reinforcing member 5. FIG. In this example, as shown in FIG. 6, the U-shaped portion 7a is bent around the mountain fold line 8b in the direction opposite to that shown in FIG.

  The present invention can also be applied to a heat exchanger core in which the flat tubes 1 are arranged in three rows in the core thickness direction. In this case, the four insertion portions 9 of the reinforcing member 5 are inserted into the flat tubes 1 in the foremost and last rows in the core thickness direction. The same applies to a heat exchanger having four or more rows of flat tubes.

  Furthermore, the reinforcing structure of the present invention can be applied to a structure in which flat tubes are arranged in only one row as shown in FIG. 10 in the thickness direction of the core. Also in this case, the thickness of the metal plate of the material is matched to ½ of the distance S between the opposed flat portions 1a of the opening of the flat tube 1, and the reinforcing member 5 is constituted by the bent body of the metal plate. . As shown in FIG. 9, the reinforcing member 5 is formed with planar L-shaped portions (7) at both ends in the longitudinal direction of the elongated connecting portion 6 in the unfolded state, and both ends of the L-shaped portions (7). First, the part is folded and overlapped to the connecting part 6 side. Then, an overlapped portion 8 is formed in which the folded end edge becomes a curved surface 5a aligned with the semicircular arc-shaped inner surface portion 1b of the flat tube 1.

Next, the overlapping portion 8 extends in a cross-sectional L shape perpendicular to the plane of the connecting portion 6 to constitute a pair of insertion portions 9. The width of the insertion portion is less than ¼ of the major axis of the cross section of the flat tube. Then, as shown in FIG. 10, the two insertion portions of the reinforcing member 5 are inserted into the openings of the flat tubes 1 only in the outermost row in the parallel direction of the flat tubes 1, and the curved surface 5 a is the flat tube 1. The semicircular arc-shaped inner surface portion 1b is fitted in contact with each other, and the fitting portion is brazed.
Further, in this description, a heat exchanger using a resin tank main body and an O-ring is taken as an example, but the same applies to a tank main body and a heat exchanger core brazed together.

1 Flat tube
1a Plane section
1b Semicircular inner surface 2 Fin 3 Heat exchanger core 4 Header plate 5 Reinforcement member
5a Curved surface 6 Connecting part
6a Edge 7 L-shaped part
7a U-shaped part

8 Superposition part
8a Valley fold line
8b Mountain fold line 9 Insertion part
10 Reinforcing groove
11 Partition
12 Tank body
13 Inlet pipe
14 Outlet pipe

17 Tapered surface
19 Support material
20 Caulking nails
21 Small flange
22 Cooling water
23 Side
24 annular groove
25 wax fillet

Claims (4)

A plurality of flat tubes (1) and fins (2) arranged in a line, and a pair of header plates (4) in which both ends of each flat tube (1) are inserted and brazed. in the reinforcing structure of the heat exchanger,
The flat tube (1) includes a pair of opposed parallel plane portions (1a) and a pair of semicircular arc-shaped inner surface portions (1b) respectively connecting both edges of each plane portion (1a). And
A reinforcing member (5) made of a bent body of a metal plate having a plate thickness w that matches 1/2 of the distance S between the opposed flat portions (1a) of the opening of the flat tube (1),
The reinforcing member (5) is formed with a flat L-shaped portion (7) in an unfolded state at both ends in the longitudinal direction of the elongated connecting portion (6), and both end portions of the L-shaped portion (7) are , superimposed folded back to the connecting portion (6) side and a semi-circular curved surface outer periphery of the cross section of the folding edges is aligned with the semicircular inner surface of the flat tube (1) the (1b) ( 5a) has a superposed part (8), and the superposed part (8) fills half of the long axis of the flat tube bent in an L-shaped cross section perpendicular to the plane of the connecting part (6). Has two inserts (9) of width not
The two insertion portions (9) of the reinforcing member (5) are inserted into the openings of the flat tubes (1) in only the outermost rows in the parallel direction of the flat tubes, and the semicircular curved surfaces (5a ) outer peripheral gap contacts without and the semi-circular inner surface portion (1b) of the flat tubes (1b) of, is fitted on only both ends of the long axis direction of the opening of the flat tube (1), the fitting portion A heat exchanger reinforcement structure characterized by being brazed. A plurality of flat tubes (1) and fins (2) arranged in a plurality of rows, and a pair of header plates (4) in which both ends of each flat tube (1) are inserted and brazed. in the reinforcing structure of the heat exchanger,
The flat tube (1) includes a pair of opposed parallel plane portions (1a) and a pair of semicircular arc-shaped inner surface portions (1b) respectively connecting both edges of each plane portion (1a). And
A reinforcing member (5) made of a bent body of a metal plate having a plate thickness w that matches 1/2 of the distance S between the opposed flat portions (1a) of the opening of the flat tube (1),
The reinforcing member (5) has a U-shaped flat portion (7a) formed outwardly at its both ends in the longitudinal direction of the elongated connecting portion (6) in an unfolded state, and the U-shaped portion ( Both end portions of 7a) are folded and overlapped to the connecting portion (6) side, and the outer periphery of the cross-section of the folded end edge is aligned with the semicircular arc-shaped inner surface portion (1b) of the flat tube (1). The flat tube has a superposed portion (8) to be a semicircular curved surface (5a), and the superposed portion (8) is bent in a cross-sectional L shape perpendicular to the plane of the connecting portion (6). Has four inserts (9) with a width less than half of the long axis of
Each of the four insertion portions (9) of the reinforcing member (5) is inserted into the opening of a pair of adjacent flat tubes (1) in the front row and the last row at the corner of the heat exchanger core. semi-circular inner surface (1b) in the gap contact without and and the outer periphery flat tube semicircular curved surface (5a) (1b), the forwardmost portion of the long axis direction of the opening of their flat tube (1) and A reinforcing structure for a heat exchanger, characterized in that it is fitted only at the rearmost end portion and the fitting portion is brazed. In the reinforcement structure of the heat exchanger according to claim 1 or 2,
A reinforcing structure of a heat exchanger in which a tip edge of each insertion portion (9) of the reinforcing member (5) is formed on a tapered surface (17). In the reinforcement structure of the heat exchanger in any one of Claims 1-3,
At the center of the plane of the heat exchanger core, one header plate (4) is provided with a two-pass partition (11), and the reinforcement is applied to the flat tubes (1) on both sides adjacent to the partition (11). Reinforcement structure of heat exchanger with brazing member (5).

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