JP2006017429A - Side plate for heat exchanger, and heat exchanger using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce longitudinal warpage of a side plate by an easy crushed shape without causing enlargement of a pressing device. <P>SOLUTION: The side plate for the heat exchanger is arranged on an end of a core part 13 comprising a tube 11 and a fin 12. It has an elongated shape with a U-shaped cross section composed of a bottom face part 21, and bent parts 22 and 23 formed by bending the bottom face part 21 from both width-direction sides. A multiplicity of recessed parts 24 extending in the width-direction is formed at predetermined intervals c by crushing on the bottom face part 21. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a heat exchanger side plate bent into a U-shaped section and a heat exchanger using the same, and is suitable for use in, for example, a vehicle air conditioner condenser.

  In a conventional vehicle air-conditioning condenser, a side plate bent into a U-shaped cross section is disposed at the end of a core portion formed of a flat tube and a corrugated fin. Specifically, this side plate is joined to the outermost corrugated fin of the core portion and the end of the header tank by brazing, and plays a role of reinforcing the core portion, protecting the corrugated fin, and the like.

  As shown in FIG. 5, the side plate is a long and elongated part having a U-shaped cross section composed of a bottom surface portion 21 and bent portions 22 and 23 on both sides thereof, and its length L is a condenser. It varies in the range of about 250 mm to 850 mm depending on the specifications.

  Because it is such a long part, when the flat aluminum material is bent and formed into a U-shaped section using a press die, the residual stress state of the material becomes unstable. The phenomenon of bowing in the direction occurs. In FIG. 5, a indicates the bow-like warpage.

  The reason why the warp a in the longitudinal direction of the side plate occurs will be described with reference to FIG. 6. As the bent portions 22 and 23 are bent, a compression region A is formed on the inner side of the bend and a tensile force is applied on the outer side of the bend. Region B is formed.

  As described above, since the compression region A on the inner side of the bend and the tensile region B on the outer side of the bend coexist, considering the strain in the longitudinal direction of the side plate, the elongation strain C occurs on the inner side of the bend and the compression is generated on the outer side of the bend. Distortion D occurs. As a result, the side plate is in an unstable stress state with stress due to the coexistence of compression and tension. For this reason, a phenomenon occurs in which the side plate warps in a bow shape in the longitudinal direction.

  The present inventors have confirmed that the bow-shaped warpage a reaches 5.6 mm when the length L = 814 mm.

  When such a large warp a occurs, it becomes difficult to assemble the end portion of the side plate in the longitudinal direction to the end portion of the header tank in the core assembling step before the condenser is integrally brazed. Further, in the integral brazing process of the condenser, a gap due to the warp a is generated between the side plate and the corrugated fin, which causes poor bonding of the corrugated fin.

  Therefore, the present inventors apply a pressing force in the height direction h to the bent portions 22 and 23 of the side plate, so-called “upsetting”, increase the back pressure applied to the bottom surface portion 21 of the side plate, and the like. However, all of these measures apply pressure to a wide range of pressure areas over the entire length of the side plate in the longitudinal direction, so a large pressure is required and a large press device is required. It becomes. For this reason, since equipment cost rises, it cannot be said that it is a practical countermeasure.

  In view of the above points, an object of the present invention is to reduce the warpage in the longitudinal direction of a side plate with a simple crushing shape without causing an increase in the size of a press device.

In order to achieve the above object, the invention according to claim 1 is a heat exchanger side plate disposed at an end of a core portion (13) composed of a tube (11) and a fin (12),
It has an elongated shape with a U-shaped cross section composed of a bottom surface portion (21) and bent portions (22, 23) formed by bending from both sides in the width direction of the bottom surface portion (21).
A plurality of recesses (24) extending in the width direction are formed in the bottom surface portion (21) by crushing at a predetermined interval (c).

  According to this, not only the bending inner part of the side plate but also the bending outer part can be formed as a compression region by forming a large number of recesses (24) in the side plate bottom face part (21) by crushing.

  For this reason, a side plate can be made into the stable stress state without a stress, As a result, the curvature of a side plate longitudinal direction can be reduced.

  Moreover, the concave portion (24) only needs to be partially crushed at a predetermined interval (c) on the bottom surface portion (21), and it is not necessary to press the entire surface of the bottom surface portion (21) with a high pressure. Increase in size can be suppressed.

  In the side plate for a heat exchanger according to claim 1, the concave portion (24) can be formed on the inner surface of the bottom surface portion (21).

  Further, in the heat exchanger side plate according to claim 1, as in the invention according to claim 3, the concave portion (24) may be formed on the outer surface of the bottom surface portion (21).

  In the heat exchanger side plate according to any one of claims 1 to 3 as in the invention described in claim 4, if the recess (24) has an arcuate cross section, the recess (24) Since the molding can be performed smoothly, the pressing force for molding the recess (24) can be reduced.

  In the heat exchanger side plate according to any one of claims 1 to 4, as in the invention according to claim 5, the concave portion (24) is formed simultaneously with the bending of the bent portions (22, 23). it can.

  In the heat exchanger side plate according to any one of claims 1 to 4, as in the invention according to claim 6, the concave portion (24) is formed after the bending of the bent portions (22, 23). May be.

In invention of Claim 7, the core part (13) which consists of a tube (11) and a fin (12),
A side plate (19, 20) disposed at an end of the core portion (13),
The side plate (19, 20) is characterized by a heat exchanger constituted by the side plate for a heat exchanger according to any one of claims 1 to 6.

  Thereby, the heat exchanger which can exhibit the effect of Claims 1-7 can be provided.

According to an eighth aspect of the present invention, in the heat exchanger according to the seventh aspect, the header tanks (14, 15) in which the ends of the tubes (11) communicate with the longitudinal ends of the tubes (11), respectively. Is placed,
The fin (12) is a corrugated fin (12);
The tube (11), the corrugated fin (12) and the header tank (14, 15) are integrally brazed together,
The side plates (19, 20) are integrally brazed to the end portions of the corrugated fins (12) and the header tanks (14, 15) located at the end portions of the core portion (13). And

  According to this, in the heat exchanger assembled by brazing, the side plate (19, 20) and the corrugated fin (12) are improved in adhesion by reducing the warpage of the side plate (19, 20). As a result, the workability of assembling the side plates (19, 20) to the end portions of the header tanks (14, 15) can be improved.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

(First embodiment)
This embodiment relates to a vehicle air-conditioning condenser. First, an outline of a vehicle air-conditioning condenser will be described with reference to FIG. As is well known, the condenser 10 is connected to the refrigerant discharge side of the compressor in the refrigeration cycle, and cools and condenses the discharge gas refrigerant of the compressor with outside air.

  The condenser 10 has a core portion 13 composed of a plurality of flat tubes 11 and corrugated fins 12 extending in the horizontal direction, and a header tank 14 extending in the vertical direction in a substantially cylindrical shape on the left and right sides of the core portion 13. 15 is disposed, and both end portions of the flat tube 11 communicate with the inside of the header tanks 14 and 15.

  An inlet joint 16 into which the discharge gas refrigerant of the compressor flows is joined to the upper part of one header tank 14, and the refrigerant condensed and supercooled in the core part 13 at the lower part of the other header tank 15. Is connected to the outlet joint 17 through which the gas flows out of the condenser.

  Moreover, the condenser 10 of this embodiment comprises the condensation part 13a which condenses a gas refrigerant in the upper part of the core part 13, and the supercooling part 13b which supercools the liquid refrigerant after condensation in the lower part of the core part 13. Is configured. For this reason, the liquid receiver 18 is integrally formed in one header tank 14, the refrigerant at the outlet of the condenser 13 a is introduced into the liquid receiver 18, and the refrigerant gas-liquid is separated inside the liquid receiver 18. And only a liquid refrigerant is made to flow into supercooling part 13b.

  On the other hand, side plates 19 and 20 are arranged at the end portions on both the upper and lower sides of the core portion 13. The side plates 19 and 20 are elongated in the horizontal direction on both the upper and lower sides of the core portion 13 and are bent to have a U-shaped cross section.

  Both ends in the longitudinal direction of the upper side plate 19 are joined to the upper ends of the header tanks 14 and 15. Further, the U-shaped bottom surface portion of the upper side plate 19 contacts and is joined to the uppermost corrugated fin 12 of the core portion 13.

  Both ends in the longitudinal direction of the lower side plate 20 are joined to the lower ends of the header tanks 14 and 15. In addition, the U-shaped bottom surface portion of the lower side plate 20 contacts and is joined to the lowermost corrugated fin 12 of the core portion 13. A plurality of attachment holes 19a and 20a are formed in the side plates 19 and 20, respectively, and the condenser 10 is attached to the vehicle body side by means such as screwing using the attachment holes 19a and 20a.

  By the way, the condenser constituent members 11, 12, and 14 to 20 shown in FIG. 1 are all formed of an aluminum alloy and assembled to the structure shown in FIG. 1, and the assembly is held by a jig in the heating furnace. Carry in. In this heating furnace, the assembly is heated to a temperature higher than the melting point of the brazing material so that the members are integrally brazed.

  For this reason, in order to smoothly perform the condenser assembly before the brazing process and to ensure good brazing properties, the side plates 19 and 20 have an arcuate warpage a in the longitudinal direction (see FIG. 6 described above). ) Is as small as possible.

  Therefore, a countermeasure for suppressing the bow-shaped warp a according to the present embodiment will be described with reference to FIG. 2A is a partially broken perspective view of the side plates 19 and 20, FIG. 2B is a cross-sectional view of the main portions of the side plates 19 and 20, and FIG. 2C is the side plates 19 and 20. It is principal part sectional drawing of the width direction (direction orthogonal to a longitudinal direction).

  The side plates 19 and 20 have a U-shaped cross section including a bottom surface portion 21 and bent portions 22 and 23 located on both the left and right sides of the bottom surface portion 21 in the width direction. The material of the side plates 19 and 20 is an aluminum bear material that is not clad with a brazing material, and in this example, JISA3003 is used, and the thickness t is, for example, 1.6 mm.

  A plurality of concave portions 24 having a minute depth b are formed in parallel on the U-shaped inner side surface of the bottom surface portion 21 with a constant interval c over the entire length of the side plates 19 and 20. The recess 24 is elongated in the width direction of the bottom surface 21, and the cross-sectional shape of the recess 24 is an arc shape (R shape) having a predetermined radius as shown in FIG. The depth b is a minute amount of about 0.04 mm, for example. The width d of the recess 24 is 1.5 mm, for example.

  The length f of the recess 24 is 8 mm. Here, since the width dimension e of the bottom surface portion 21 is, for example, 12.8 mm, the length f of the recess 24 occupies a ratio of 60% or more with respect to the width dimension e of the bottom surface portion 21.

  Inclined surfaces 24 a are formed at both ends in the longitudinal direction of the recess 24, and both ends in the longitudinal direction of the recess 24 are smoothly connected to the inner surface of the bottom surface portion 21. Here, the angle θ formed by the inclined surface 24a and the vertical line of the bottom surface portion 21 is, for example, 75 °.

  The above-described forming of the recess 24 can be performed simultaneously with the bending of the side plates 19 and 20. That is, the bottom surface portion 21 is partially crushed at a constant interval c into a press die for bending a flat aluminum material into a U-shaped cross section having the bottom surface portion 21 and the bent portions 22 and 23. A projecting portion (rib shape) having an arcuate cross section is formed. Accordingly, a large number of the concave portions 24 can be formed by crushing at the same time as the bending of the U-shaped section is performed using the press die.

  Here, the reason why the warpage of the side plates 19 and 20 can be suppressed by the crushing process of the concave part 24, as shown in FIG. 3, the compressive stress E can be generated by the crushing process of the concave part 24. A compression region F is also formed at the bent outer portion.

  That is, in this embodiment, the tensile region B of the bent outer portion in FIG. 6 is switched to the compressed region F, and both the bent inner portion and the bent outer portion become the compressed regions A and F. Become.

  As a result, the side plate longitudinal extension strain is generated in both the bending inner portion and the bending outer portion, and by balancing the elongation strain in the bending inner portion and the bending outer portion, an arcuate shape in the side plate longitudinal direction is obtained. Warpage can be suppressed.

  The inventor measured the size of the bow-shaped warp a by changing the interval c of the recesses 24 under the above dimension design example at the total length L = 814 mm, and the following results were obtained.

Interval c = 40mm → Warpage a = 2.6mm
Interval c = 30mm → Warp a = 1.5mm
Interval c = 20mm → Warp a = 0.3mm
Thus, it has been found that the warp a = 5.6 mm in the conventional example of FIG.

  From the above examination results, it can be seen that the warp a can be reduced as the interval c is reduced. However, if the interval c is excessively reduced, the compression region F on the outer side of the bending wins over the compression region A on the inner side of the bending. , 20 is warped in the opposite direction to the warp a in FIG. 5, the lower limit value of the interval c is preferably set to around 20 mm in this embodiment.

  According to the study of the present inventor, the concave portion 24 may be formed after the side plates 19 and 20 are bent and then the concave portion 24 may be formed independently. Even in this case, it has been confirmed that the bow-shaped warp a can be similarly suppressed.

  On the other hand, when the concave portion 24 is independently formed on the flat plate-like aluminum material before the side plates 19 and 20 are bent, the flat plate-like aluminum material is formed with the residual stress accompanying the formation of the concave portion 24 as shown in FIG. The phenomenon of warping in the opposite direction to warpage a occurs. This warpage makes it difficult to insert a flat aluminum material into the press die. Therefore, it is not preferable to form the recess 24 before the side plates 19 and 20 are bent.

(Second Embodiment)
In the first embodiment, the concave portions 24 are formed on the inner side surface of the bottom surface portion 21 in the side plates 19 and 20 having a U-shaped cross section. However, in the second embodiment, as shown in FIG. The recess 24 is formed.

  As described above, it has been confirmed that even when the concave portion 24 is formed on the outer surface of the bottom surface portion 21, the bow-shaped warp a can be suppressed as in the first embodiment.

  However, as can be seen from FIG. 1, the corrugated fins 12 are joined to the outer side surfaces of the bottom surface portions 21 of the side plates 19 and 20 by brazing. The bondability (brazing property) with the fin 12 is deteriorated. Therefore, from the viewpoint of the bondability, the first embodiment is preferable to the second embodiment.

(Other embodiments)
In the above-described embodiment, the cross-sectional shape of the concave portion 24 is an arc shape. However, even if the cross-sectional shape of the concave portion 24 is a trapezoidal shape, the effect of suppressing the bow-shaped warpage a can be obtained similarly. However, since the trapezoidal shape is a shape in which flat surfaces are combined, the pressing force for crushing the concave portion is increased as compared with the arc shape.

  In the above-described embodiment, the interval c of the recesses 24 is constant over the entire length direction of the bottom surface portion 21, but the interval c of the recesses 24 may be changed in the longitudinal direction of the bottom surface portion 21 as necessary.

  In the above-described embodiment, the example in which the present invention is applied to the side plates 19 and 20 in the condenser of the refrigeration cycle has been described. However, the side plate having a U-shaped cross section has heat such as a radiator that cools cooling water of the vehicle engine. Since the present invention is also installed in the exchanger, the present invention can be similarly applied to a heat exchanger such as this radiator.

It is a perspective view which shows the outline | summary of the whole structure of the condenser to which this invention is applied. (A) is a partially broken perspective view which shows the side plate by 1st Embodiment of this invention, (b) is principal part sectional drawing of the longitudinal direction of a side plate, (c) is the principal part of the width direction of a side plate It is sectional drawing. It is explanatory drawing of the curvature suppression effect of the side plate by 1st Embodiment. It is a partially broken perspective view which shows the side plate by 2nd Embodiment of this invention. It is a perspective view which shows the side plate by a prior art. It is explanatory drawing of the cause of curvature of the side plate by a prior art.

Explanation of symbols

11 ... Tube, 12 ... Fin, 13 ... Core part, 19, 20 ... Side plate,
21 ... Bottom part, 22, 23 ... Bending part, 24 ... Concave part.

Claims (8)

A heat exchanger side plate disposed at an end of a core (13) comprising a tube (11) and fins (12),
It has an elongated shape with a U-shaped cross section composed of a bottom surface portion (21) and bent portions (22, 23) formed by bending from both sides in the width direction of the bottom surface portion (21).
A side plate for a heat exchanger, wherein a plurality of recesses (24) extending in the width direction are formed on the bottom surface portion (21) by crushing at a predetermined interval (c). The side plate for a heat exchanger according to claim 1, wherein the recess (24) is formed on an inner surface of the bottom surface (21). The side plate for a heat exchanger according to claim 1, wherein the concave portion (24) is formed on an outer surface of the bottom surface portion (21). The side plate for a heat exchanger according to any one of claims 1 to 3, wherein the recess (24) has a circular arc shape in cross section. The side plate for a heat exchanger according to any one of claims 1 to 4, wherein the concave portion (24) is formed simultaneously with the bending of the bent portion (22, 23). The side plate for a heat exchanger according to any one of claims 1 to 4, wherein the concave portion (24) is formed after the bending portion (22, 23) is bent. A core portion (13) comprising a tube (11) and a fin (12);
A side plate (19, 20) disposed at an end of the core portion (13),
A heat exchanger, wherein the side plate (19, 20) is constituted by the side plate for a heat exchanger according to any one of claims 1 to 6. Header tanks (14, 15) with which the ends of the tubes (11) communicate with each other at both ends in the longitudinal direction of the tubes (11),
The fin (12) is a corrugated fin (12);
The tube (11), the corrugated fin (12) and the header tank (14, 15) are integrally brazed together,
The side plates (19, 20) are integrally brazed to the end portions of the corrugated fins (12) and the header tanks (14, 15) located at the end portions of the core portion (13). The heat exchanger according to claim 7.

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