WO2021261005A1

WO2021261005A1 - Heat exchanger and method for manufacturing same

Info

Publication number: WO2021261005A1
Application number: PCT/JP2021/005667
Authority: WO
Inventors: 孝仁中島; 泰行李; 健二名越
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2020-06-22
Filing date: 2021-02-16
Publication date: 2021-12-30
Also published as: JP2022001817A; CN115917241A

Abstract

This heat exchanger is provided with: a plate fin laminated body acquired by laminating plate fins having a flow channel with gaps; end plates provided on both ends of the plate fin laminated body in the lamination direction; and a sleeve which is joined with the end plates and communicated with the flow channel of the plate fin. The end plates are configured by a laminated body structure of a plurality of brazing sheets. As a result, it is possible to provide a highly reliable heat exchanger which has a configuration capable of positively joining the end plates with a charging tube or a discharging tube, and has high stiffness while achieving weight reduction, and a method for manufacturing the same.

Description

Heat exchanger and its manufacturing method

The present disclosure relates to a heat exchanger, and more particularly to a heat exchanger of a laminated plate fin configured by laminating plate-shaped plate fins through which a refrigerant flows, and a method for manufacturing the same.

Heat exchangers used to exchange heat energy between fluids with different heat energies are used in many products, especially laminated plate fin heat exchangers, for example households and vehicles. Used in air exchangers, computers, and various electrical equipment.

The heat exchanger of the laminated plate fin exchanges heat between the fluid (refrigerant) flowing in the flow path formed in the plate-shaped plate fin and the fluid (air) flowing between the laminated plate fins. It is a form to do.

In the field of heat exchangers for laminated plate fins as described above, various configurations have been proposed for the purpose of reducing the size and weight and providing highly reliable products (for example, Patent Document 1-). 4).

Japanese Unexamined Patent Publication No. 2012-112562 Japanese Unexamined Patent Publication No. 09-001385 Japanese Patent No. 3283471 Japanese Patent No. 5714387

The heat exchanger of the laminated plate fin has end plates arranged at both ends in the laminated direction of the plate fins. The end plate has substantially the same shape as the plate fins in a plan view (shape seen from the stacking direction), and the supply pipe to which the refrigerant is supplied to both ends of one end plate and the discharge pipe to which the refrigerant is discharged are discharged. Is joined.

As described above, in the heat exchanger of the laminated plate fins, end plates are provided so as to be sandwiched from both sides of the laminated plate fins, and the supply pipe and the discharge pipe are joined to the end plates. For this reason, in the heat exchanger, it is necessary to provide an end plate that can be reliably joined to the supply pipe and the discharge pipe, has strength, and has high rigidity, and has a highly reliable configuration. there were. However, such an end plate is heavy, difficult to process, and has problems in corrosiveness.

The present disclosure solves the conventional problems, has a structure in which the end plate can be reliably joined to the supply pipe and the discharge pipe, and maintains high rigidity while reducing the weight, and has high reliability. The purpose is to provide a exchanger and a method for manufacturing the same.

In order to achieve the above object, the heat exchanger of one aspect of the present disclosure is
A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A heat exchanger provided with a sleeve of an inlet or outlet pipe that is joined to the end plate and communicates with the flow path of the plate fins.
The end plate has a laminated structure of a plurality of brazing sheets.

Further, the method for manufacturing the heat exchanger according to one aspect of the present disclosure is described.
A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A method of manufacturing a heat exchanger provided with a sleeve of an inlet pipe or an exhaust pipe which is joined to the end plate and communicates with the flow path of the plate fin.
The end plate is formed by laminating a plurality of brazing sheets and alloying them.

As described above, according to the heat exchanger of the present disclosure and the manufacturing method thereof, the end plate has a structure that can be reliably joined to the sleeves such as the supply pipe and the discharge pipe, and has high rigidity while reducing the weight. It can be held to provide a highly reliable heat exchanger.

A perspective view showing the appearance of the heat exchanger of the laminated plate fin of the first embodiment according to the present disclosure. Sectional drawing which shows typically the brazing sheet used in Embodiment 1. Graph showing the results of strength experiments on heat exchanger end plates A cross-sectional view schematically showing a heat exchanger composed of an end plate of a single aluminum alloy in Leak Experiment 1. A cross-sectional view schematically showing a heat exchanger configured by an end plate having a laminated structure in Leak Experiment 1. Cross-sectional photograph of a heat exchanger composed of an end plate of a single aluminum alloy in Leak Experiment 1 Cross-sectional photograph of a heat exchanger composed of end plates having a laminated structure in Leak Experiment 1. Aluminum-Silicon (Al-Si) Binary Phase Diagram A graph showing the experimental results in the leak experiment 2 together with a cross-sectional photograph. Cross-sectional photograph of a heat exchanger composed of an end plate of a single aluminum alloy when a corrosiveness experiment was conducted. Cross-sectional photograph when a corrosive experiment was conducted on a heat exchanger composed of end plates with a laminated structure.

Hereinafter, as a specific embodiment of the heat exchanger of the present disclosure, the heat exchanger of the laminated plate fin will be described with reference to the attached drawings. The heat exchanger of the present disclosure is not limited to the configuration of the heat exchanger of the laminated plate fins described in the following embodiments, and is a technique having the technical features described in the following embodiments. It includes those based on the same technology as the idea.

Further, the shapes, configurations, methods (processes, order of processes) and the like shown in the following embodiments are examples, and the invention is not limited to the contents of the present disclosure. Among the elements in the following embodiments, the elements not described in the independent claim indicating the highest level concept are described as arbitrary elements. In the drawings, each element is schematically drawn for easy understanding.

First, various aspects of the heat exchanger of the present disclosure and the method for manufacturing the same will be illustrated.
The heat exchanger of the first aspect according to the present disclosure is
A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A heat exchanger provided with a sleeve of an inlet or outlet pipe that is joined to the end plate and communicates with the flow path of the plate fins.
The end plate has a laminated structure of a plurality of brazing sheets.

The heat exchanger of the second aspect according to the present disclosure may have a configuration in which the brazing sheet in the first aspect has a first clad layer on at least one surface of the core material.

In the heat exchanger of the third aspect according to the present disclosure, in the second aspect, the core material and the material constituting the first clad layer are aluminum alloys, and the first clad layer is silicon. , May be composed of an aluminum alloy containing zinc.

The heat exchanger of the fourth aspect according to the present disclosure may have a configuration in which the brazing sheet has a second clad layer on the other surface of the core material in the second or third aspect.

In the heat exchanger of the fifth aspect according to the present disclosure, the second clad layer in the fourth aspect may be made of an aluminum alloy containing silicon.

In the heat exchanger of the sixth aspect according to the present disclosure, the first clad layer in any one of the second to fifth aspects is an aluminum alloy layer containing silicon and aluminum containing zinc. It may have a laminated structure sandwiched between alloy layers.

The heat exchanger of the seventh aspect according to the present disclosure is another metal in which a part of the laminated structure of the brazing sheet is different from the brazing sheet in any one of the first to sixth aspects. It may include a reinforcing sheet composed of.

The method for manufacturing the heat exchanger according to the eighth aspect according to the present disclosure is as follows.
A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A method of manufacturing a heat exchanger provided with a sleeve of an inlet pipe or an exhaust pipe which is joined to the end plate and communicates with the flow path of the plate fin.
The end plate is formed by laminating a plurality of brazing sheets and alloying them.

In the method for manufacturing a heat exchanger according to a ninth aspect according to the present disclosure, in the eighth aspect, the brazing sheet has a first clad layer formed on at least one surface of a core material, and the first clad is formed. The layer may be formed of an aluminum alloy containing silicon and zinc.

In the method for manufacturing a heat exchanger according to the tenth aspect of the present disclosure, in the ninth aspect, the first clad layer sandwiches an aluminum alloy layer containing silicon between aluminum alloy layers containing zinc. However, it may have a laminated structure.

In the method for manufacturing the heat exchanger according to the eleventh aspect according to the present disclosure, in the ninth aspect, the brazing sheet may have a second clad layer on the other surface of the core material.

In the method for manufacturing the heat exchanger according to the twelfth aspect of the present disclosure, the second clad layer may be formed of an aluminum alloy containing silicon in the eleventh aspect.

In the method for manufacturing a heat exchanger according to the thirteenth aspect according to the present disclosure, in the eleventh or twelfth aspect, the clearance volume of the facing joint portion between the end plate and the sleeve is the said in the end plate. It may be set according to the silicon concentration of the first clad layer and the second clad layer.

(Embodiment 1)
Hereinafter, the heat exchanger according to the first embodiment of the present disclosure and the manufacturing method thereof will be described with reference to the accompanying drawings. FIG. 1 is a perspective view showing the appearance of the heat exchanger (hereinafter, simply referred to as a heat exchanger) 1 of the laminated plate fin of the first embodiment. As shown in FIG. 1, in the heat exchanger 1 of the first embodiment, the supply pipe 4 to which the refrigerant as the first fluid is supplied and the plurality of plate fins 2a having a rectangular plate shape have a gap. It is provided with a plate fin laminated body 2 formed by laminating the plates and a discharge pipe 5 for discharging a refrigerant flowing through a flow path formed in the plate fins 2a.

In the heat exchanger 1 of the first embodiment, the supply pipe 4 and the discharge pipe 5 have substantially the same configuration, and the function corresponding to the operation at that time is used as a name. In the present disclosure, the supply pipe 4 and the discharge pipe 5 are collectively referred to as a sleeve (4, 5).

End plates 3 are arranged at both ends of the plate fin laminate 2 in the stacking direction, and the end plate 3 has substantially the same shape as the rectangular plate fin 2a in a plan view. A supply pipe 4 or a discharge pipe 5 is joined to both ends of one end plate 3 in the longitudinal direction. In the configuration of the first embodiment, the supply pipe 4 or the discharge pipe 5 is joined to both ends of one of the end plates 3, respectively, but the heat exchanger 1 is used according to the specifications of the apparatus in which the heat exchanger 1 is used. , The supply pipe 4 may be joined to one end plate 3, and the discharge pipe 5 may be joined to the other end plate 3.

In the following embodiment 1, the stacking direction of the plate fin laminate 2 in the heat exchanger 1 is the vertical direction as shown in FIG. 1, and the position of one end plate 3 provided on the plate fin laminate 2 is on the upper side. The position of the other end plate 3 will be described as the lower side. However, in a state where the heat exchanger 1 is provided in an apparatus (for example, an air conditioner), the stacking direction thereof is not specified in the vertical direction (vertical direction).

The end plates 3 arranged at both ends of the plate fin laminate 2 in the stacking direction are fixed to each other at predetermined intervals by positioning means (for example, positioning bolts), and the plate fin laminate 2 is sandwiched. is doing. The positioning means for maintaining and fixing the end plates 3 at both ends at predetermined intervals has a function of positioning for each of the stacked plate fins 2.

In the heat exchanger 1 of the first embodiment, the refrigerant as the first fluid flows through the flow path formed in each plate fin 2a of the plate fin laminate 2. On the other hand, the air, which is the second fluid, is configured to pass through the gap formed between the stacks of the plate fins 2a in the plate fin laminate 2. In the heat exchanger 1 configured in this way, heat exchange is performed between the first fluid and the second fluid in the plate fin laminated body 2.

Each of the plurality of plate fins 2a constituting the plate fin laminate 2 in the heat exchanger 1 of the first embodiment is bonded (brazing) by laminating two brazing sheets so as to face each other to form a flow path. It is a configuration to be done. The plate fins 2a configured in this way are joined (brazed) by being pressurized and heated in a state where a plurality of the plate fins 2a are laminated to form the plate fin laminated body 2. When the plate fin laminate 2 is heated and joined, the end plate 3 and the

sleeves

4 and 5 may be simultaneously heated and joined (brazing to form a heat exchanger).

In the heat exchanger 1 of the first embodiment, the end plate 3 joined to both sides of the plate fin laminate 2 has a laminate structure in which a plurality of brazing sheets 10 (see FIG. 2) are laminated and alloyed. ing. FIG. 2 is a cross-sectional view schematically showing the brazing sheet 10 used in the first embodiment.

[Blazing sheet]
The brazing sheet 10 laminated and used as the end plate 3 in the heat exchanger 1 of the first embodiment is made of an aluminum alloy used for the heat exchanger. Specifically, for example, as shown in FIG. 2, each brazing sheet 10 has a clad layer on both sides of the core material 11, and a first clad layer (sacrificial anticorrosion layer) 12 is formed on one surface. A second clad layer (wazing material layer) 13 is formed on the other surface. The first clad layer 12 also functions as a brazing material layer. The first clad layer 12 is coated on one surface of the core material 11, and the second clad layer 13 is on the other surface of the core material 11, that is, on the surface opposite to the surface on which the first clad layer 12 is coated. It is covered. The materials constituting the core material 11, the first clad layer 12, and the second clad layer 13 are all aluminum alloys. In the first embodiment, as will be described later, the first clad layer 12 is an aluminum alloy containing silicon (Si) and zinc (Zn), and the second clad layer 13 is an aluminum alloy containing at least Si. Is.

The brazing sheet 10 in the present disclosure may have a configuration in which a clad layer is provided only on one surface of the core material 11. In this case, the clad layer is an aluminum alloy containing Si and Zn. The core material 11 may be an aluminum alloy that can realize the physical properties required according to various conditions such as the type or structure of the heat exchanger.

The aluminum alloy of the core material 11 used in the present disclosure is, for example, in the field of heat exchangers, typically 3000 series (aluminum-manganese (Al-Mn) based alloy) and 5000 series (aluminum-magnesium (Al)). -Mg) based alloy), 6000 series (aluminum-magnesium-silicon (Al-Mg-Si) based alloy) and the like can be mentioned, but the present invention is not limited thereto.

The aluminum alloy used as the brazing material of the second clad layer (wazing material layer) 13 of the first embodiment may be an alloy containing silicon (Si), that is, an aluminum-silicon (Al-Si) based alloy. .. The content (concentration) of Si in the brazing material is not particularly limited, and may be within a range suitable for use as a brazing material.

The Al—Si alloy as the brazing material may contain an element other than Si as long as it does not affect the function as the brazing material. Further, the Al—Si alloy as the brazing material may contain various elements as unavoidable impurities.

The aluminum alloy used as the material of the first clad layer (sacrificial anticorrosion layer) 12 contains zinc (Zn) in order to exert a sacrificial anticorrosion effect. Further, in the brazing sheet 10 of the first embodiment, since the first clad layer 12 also serves as a brazing material layer, it contains Si as well as the brazing material. Therefore, the aluminum alloy used as the first clad layer 12 may be an aluminum-silicon-zinc (Al-Si-Zn) alloy.

The Al—Si—Zn-based alloy as the material of the first clad layer 12 may contain elements other than Si and Zn as long as it does not affect the sacrificial anticorrosion action and the function as a brazing material. .. Further, the Al—Si—Zn-based alloy as the material of the first clad layer 12 may contain various elements as unavoidable impurities.

The type of aluminum alloy specifically used as the material of the first clad layer 12 and the second clad layer 13 is not particularly limited, but all of them are typically 4000 series (aluminum-silicon (Al-Si) based alloys). Can be used. In the first clad layer 12, a 4000-based aluminum alloy to which Zn is added is used.

In the brazing sheet 10 in the heat exchanger of the first embodiment, the clad ratio in the materials of the first clad layer 12 and the second clad layer 13 is not particularly limited, and may be mentioned within a general range. The general clad ratio (ratio of the thickness of the clad layer to the total thickness) may be, for example, in the range of 2 to 30%, and may be in the range of 3 to 20%. Further, the thickness of the brazing sheet 10 and the thicknesses of the core material 11, the first clad layer 12, and the second clad layer 13 are not particularly limited, and the heat exchange to be configured or manufactured by the brazing sheet 10 is not particularly limited. It can be set as appropriate according to the type of vessel, parts, and the like.

In the brazing sheet 10 in the heat exchanger of the first embodiment, a plurality of brazing sheets 10 are superposed and the first clad layer 12 and the second clad layer 13 are melted at a high temperature (580 ° C. or higher). By brazing, the laminated brazing sheets 10 are joined to each other. The laminated body of the brazing sheet 10 manufactured in this way is used as the end plate 3 in the heat exchanger of the first embodiment.

[Strength experiment]
The inventor has performed a strength experiment on an end plate 3 having a laminated structure in the present disclosure and a conventional end plate 30 (see FIG. 4) composed of a conventional aluminum alloy simple substance (Al—Mn-based alloy). Was done.

FIG. 3 is a graph showing the results of the strength experiment conducted by the inventor. In FIG. 3, (a) shows the result of the tensile test, and (b) shows the result of the bending test. In the graph of the tensile test shown in FIG. 3A, the vertical axis indicates stress [MPa] and the horizontal axis indicates elongation [mm]. Further, in the bending test graph shown in (b), the vertical axis indicates stress [MPa] and the horizontal axis indicates displacement [mm].

In the strength experiment shown in FIG. 3, as an example of the end plate 3 having a laminated body structure in the present disclosure, a laminated body A formed by laminating 10 sheets of a 0.2 mm thick clad material and a 0.8 mm thick clad are used. The laminated body B formed by laminating two materials and the 2.0 mm thickness of the aluminum alloy 3003 alone as the conventional end plate 30 were used as the single body C. The laminated body A and the laminated body B were produced by applying flux to a clad material, laminating them, placing a weight on them from above, and brazing them. The brazing temperature of the laminated body A and the laminated body B was 610 ° C., and the layers were heated in the same batch.

In the laminated body A, an aluminum alloy of 3003 (0.156 mm thick) is used as the core material 11, and an aluminum alloy of Al-4.4Si-2.0Zn (0.015 mm thick) is used as the first clad layer 12. As the second clad layer 13, an aluminum alloy of Al-11.0Si (thickness of 0.021 mm) was used. The measured value of the total thickness of the laminated body A was 2.09 mm in the tensile test and 1.98 mm in the bending test.

Further, in the laminated body B, an aluminum alloy of 3003 + 0.5Cu (thickness of 0.64 mm) is used as the core material 11, and an aluminum alloy of 4343 + 1 Zn (thickness of 0.08 mm) is used as the first clad layer 12. The two clad layer 13 was the same as the first clad layer 12, and an aluminum alloy (thickness of 0.08 mm) of 4343 + 1 Zn was used. The measured value of the total thickness of the laminated body B was 1.60 mm in the tensile test and 1.56 mm in the bending test.

The measured value of the total thickness of the single body C of the aluminum alloy (3003) was 2.02 mm in the tensile test and 2.01 mm in the bending test.

As shown in the graph of the tensile test of FIG. 3A, it can be understood that the laminated body A and the laminated body B clearly have stronger tensile strength than the single body C. Further, as shown in the graph of the bending test of FIG. 3B, the laminated body A (measured total thickness 1.98 mm) is thinner than the simple substance C (measured total thickness 2.01 mm). Regardless, it had a stronger bending strength than the simple substance C.

As described above, the reason why the end plate 3 in the present disclosure has high rigidity and the strength is increased by the laminated structure is that the alloy components (Si, Zn, etc.) are added to the brazing sheet. It is considered that this is because the solid solution is strengthened and the precipitation is strengthened. It is considered that the addition of elements such as Si and Zn to the aluminum alloy inhibits the motion of dislocations and increases the strength. Further, regarding the core material 11, if it is heated to a temperature close to the melting point at the time of brazing, the crystal grains become coarse and the strength decreases. However, in the laminated structure of the brazing sheet 10 having the configuration of the present disclosure, the brazing sheet is used. Since the size cannot be larger than the thickness of the initial core material 11 of 10, it is possible to limit the crystal grain growth by the thickness of the core material 11.

[Leak experiment]
The inventor has created a refrigerant in a heat exchanger using an end plate 3 having a laminated structure in the present disclosure and a conventional end plate 30 composed of a conventional aluminum alloy simple substance (Al—Mn-based alloy). Leak experiment 1 was performed.

4 and 5 schematically show an enlarged joint between the sleeve (supply pipe 4 or discharge pipe 5) and the

end plates

30 and 3 in the heat exchanger when the refrigerant leak experiment 1 was performed. It is a cross-sectional view. The enlarged cross-sectional view shown in FIG. 4 schematically shows the configuration of a heat exchanger using an end plate 30 composed of 3003 alone of an aluminum alloy. The enlarged cross-sectional view shown in FIG. 5 is a diagram schematically showing the configuration of the heat exchanger of the first embodiment, and is a configuration using an end plate 3 having a laminated body structure in which a sheet (10) of a clad material is laminated. Is.

6 and 7 are cross-sectional photographs of the heat exchanger when the refrigerant leak experiment 1 was performed. FIG. 6 is a cross-sectional photograph of a heat exchanger composed of an end plate 30 using a single aluminum alloy 3003. In FIG. 6, (b) is an enlarged photograph of the joint portion between the sleeve 4 (5) and the end plate 30 surrounded by a square in the cross-sectional photograph of (a). FIG. 7 is a cross-sectional photograph of a heat exchanger composed of an end plate 3 having a laminated structure. In FIG. 7, (b) is an enlarged photograph of the joint portion between the sleeve 4 (5) and the end plate 3 surrounded by a square in the cross-sectional photograph of (a).

As shown in FIG. 7B, the first clad layer 12 and the second clad of each brazing sheet 10 constituting the end plate 3 in the entire joint surface of the end plate 3 facing the sleeve 4 (5). The layer 13 melts out as a brazing material and solidifies. That is, at the joint portion between the sleeve 4 (5) through which the refrigerant flows and the end plate 3 facing the sleeve 4, the entire joint portion is surely brazed without performing work such as newly applying a brazing material.

On the other hand, as shown in FIG. 6, in a heat exchanger using an end plate 30 made of a single aluminum alloy, a paste-like braze is formed on a joint portion facing the sleeve 4 (5) and the end plate 30. It is necessary to perform brazing after the process of applying. Further, in the configuration shown in FIG. 6, in order to improve the reliability of the joint portion, a step for receiving the end surface of the sleeve 4 (5) is formed in the end plate 30.

As described above, in the heat exchanger 1 in which the brazing sheet 10 provided with the first clad layer 12 and the second clad layer 13 is laminated as the end plate 3, the sleeve 4 (5) and the end plate 3 are used. It can be understood that the joint portion of the above is surely brazed.

Next, the inventor produced heat exchangers at different brazing temperatures using the brazing sheets 10 having different specifications in the heat exchanger 1 using the structure in which the brazing sheets 10 were laminated as the end plate 3 to prepare the refrigerant. Leak experiment 2 was performed. In the leak experiment 2, the sleeve 4 (5) having an outer diameter of 8.00 mm was brazed to the end plate 3.

Two types of clad materials D and E were used as the brazing sheet 10 of the end plate 3 used in the leak experiment 2. In the clad material D, the first clad layer 12 on the core material 11 is divided into three layers, and on the surface side (one surface side) of the core material 11, the first layer of Al-4.5 Zn, Al-. It is the second layer of 10Si and the third layer of Al-4.5Zn. As the core material 11, an aluminum alloy of 3003 + 0.5Cu was used. Further, a layer of Al-10Si is formed as a second clad layer 13 on the back surface side (the other surface side) of the core material 11. The brazing sheet 10 of the clad material D has a thickness of 200 μm. Twelve brazing sheets 10 were laminated to form an end plate 3, and a heat exchanger F was produced by brazing the end plate 3, the plate fin laminate 2, and the sleeve 4 (5).

In the clad material E, as shown in the cross-sectional view shown in FIG. 2, the first clad layer 12 is a layer of Al-4.0Si-4.0Zn. As the core material 11, an aluminum alloy of 3003 + 0.5Cu was used. Further, as the second clad layer 13, a layer of Al-7.5Si is formed. The brazing sheet 10 of the clad material E has a thickness of 200 μm. Twelve brazing sheets 10 were laminated to form an end plate 3, and a heat exchanger G was produced by brazing the end plate 3, the plate fin laminate 2, and the sleeve 4 (5).

Table 1 shows the parameters of each condition and the results of the leak experiment when the refrigerant leak experiment 2 was performed in each of the manufactured heat exchanger F and heat exchanger G. As shown in Table 1, in the production of each of the heat exchanger F and the heat exchanger G, the brazing temperature was divided into the case of 600 ° C. and the case of 610 ° C. Further, the leak experiment 2 was performed by changing the hole diameter to be bored in the end plate 3 and changing the clearance volume between the end plate 3 and the sleeve 4 (5).

In Table 1, the liquid phase ratio fk in the first clad layer 12 and the second clad layer 13 is a function of the silicon (Si) concentration Ck and the maximum ultimate temperature T at the time of brazing. The liquid phase ratio fk was calculated from the principle of the lever from the Al—Si binary phase diagram. The formula for calculating the liquid phase ratio fk is shown below. FIG. 8 shows an Al—Si binary phase diagram, in which the horizontal axis represents the composition [at%] and the vertical axis represents the temperature [° C.]. As an example, the liquid phase ratio and the solid phase ratio in a specific aluminum alloy. Shows the relationship with.

The liquid phase ratio is originally in the range of 0 to 1.0, but the liquid phase ratio fk used in the present disclosure may exceed 1.0. Silicon (Si) diffuses to the surroundings during brazing. That is, since the brazing material layer substantially spreads to the surroundings, it is the physical meaning that the liquid phase ratio takes a value of 1.0 or more in consideration of the spread. Strictly speaking, it is a more complicated calculation formula, but in this disclosure, it is treated as an approximate formula.

The liquid phase amount in Table 1 is calculated by defining it as a value obtained by adding the multiplication value of the liquid phase ratio and the thickness in the first clad layer 12 and the multiplication value of the liquid phase ratio and the thickness in the second clad layer 13. It was done.

FIG. 9 is a graph showing the results of the leak experiment 2 shown in Table 1 above together with a cross-sectional photograph. In the graph of FIG. 9, the leak experiment results of the six types of heat exchangers F using the clad material D are shown by the numbers [1] to [6], and the six types of heat exchangers G using the clad material E are shown. The leak experiment results are shown by the numbers [7] to [12]. As is clear from the graph of FIG. 9, when the clearance volume is small, there is no leakage even if the liquid phase amount is small, and when the clearance volume is large, a large liquid phase amount is required, and there is a proportional relationship. Was. The boundary line for the presence or absence of leakage can be represented by Y = (1/32) × X. Here, Y indicates the liquid phase amount [mm ³ ], and X is the clearance volume [mm ³ ].

FIG. 9 shows a cross-sectional photograph of the joint portion between the sleeve 4 (5) and the end plate 3 in the heat exchanger when there is no leak as a result of the leak experiment 2 and when there is a leak. As shown in the cross-sectional photograph when no leak occurs, the brazing material from the laminated body of the end plate 3 is between the end plate 3 composed of the laminated body of the brazing sheet 10 and the sleeve 4 (5). It can be understood that it melts, solidifies, and is firmly bonded. On the other hand, in the graph of FIG. 9, when it is below the boundary line (Y = (1/32) × X) of the presence or absence of leakage, the clearance volume is larger than the amount of the liquid phase, and it is in a perfect bonded state. is not. The clearance volume of the joint portion where the end plate 3 and the sleeve (4, 5) face each other is preferably set according to the silicon concentration of the first clad layer 12 and the second clad layer 13 in the end plate 3. As described above, according to the method for manufacturing the heat exchanger in the first embodiment, the clearance volume corresponding to the amount of the liquid phase is set, and the end plate 3 and the sleeve (4, 5) are securely joined. , It is possible to manufacture a highly reliable heat exchanger that does not cause leakage.

[Corrosive experiment]
Next, in the configuration of the heat exchanger of the first embodiment, a corrosive experiment on the end plate 3 was performed. The corrosion resistance of the laminated structure of the brazing sheet 10 was evaluated based on the SWAAT test (Sea Water Acidified Test) defined by ASTM G85-A3. As the heat exchanger used for comparison, the heat exchanger shown in FIG. 4 described above was used. The heat exchanger shown in FIG. 4 is a heat exchanger using an end plate 30 made of a single unit of aluminum alloy 3003.

FIG. 10 is a cross-sectional photograph of a heat exchanger using the end plate 30 when a corrosive experiment was conducted. (B) is an enlarged photograph of the end plate 30 surrounded by a square in the cross-sectional photograph of FIG. 10 (a). FIG. 11 is a cross-sectional photograph of a heat exchanger composed of an end plate 3 having a laminated body structure when a corrosiveness experiment is performed. In FIG. 11, (b) is an enlarged photograph of the end plate 3 surrounded by a square in the cross-sectional photograph of (a).

As shown in the cross-sectional photograph of FIG. 11 (b), in the end plate 3 having a laminated structure in which the brazing sheets 10 are laminated, the depth of corrosion is higher than that of the end plate 30 in the cross-sectional photograph of FIG. 10 (b). It can be understood that the corrosion is stopped in the clad layer in the laminated structure. In the configuration of the first embodiment, the first clad layer 12 functions as a sacrificial anticorrosion layer, and the aluminum alloy used as the material of the first clad layer 12 has zinc (in order to exhibit a sacrificial anticorrosion effect). It is considered that it contains Zn). As described above, since the end plate 3 has a laminated structure of the brazing sheet 10 provided with the sacrificial anticorrosion layer, the end plate 3 is configured to suppress corrosion in the depth direction.

As described above, in the heat exchanger described in the embodiment, since the end plate 3 has a laminated structure of the brazing sheet 10, in the method of manufacturing the heat exchanger, it can be easily molded by press working. It is possible, and a step of applying a paste-like brazing material for joining the sleeve 4 (5) or the like is not required. Further, since the end plate 3 has a structure in which the laminated body structure of the brazing sheet 10 is alloyed, it is a material having high strength performance. Further, since the brazing sheet 10 has a sacrificial anticorrosion layer (Zn component), it has a function of suppressing corrosion in the stacking direction (depth direction) of the end plate 3.

Although the end plate 3 of the heat exchanger in the embodiment has been described with the laminated structure of the brazing sheet 10 of the aluminum alloy, some of the flazing sheets 10 are made of another metal having a strength higher than that of the aluminum alloy, for example, a steel plate. Or the like may be sandwiched as a reinforcing sheet to form an end plate. That is, a structure may include a reinforcing sheet in which a part of the laminated body structure of the brazing sheet is made of another metal different from the brazing sheet. The end plate configured in this way has a structure having further strength, and can further enhance the reliability as a heat exchanger.

Further, in the end plate of the heat exchanger in the present disclosure, it is possible to easily cope with it by forming a hole for burying a different kind of metal such as a sensor or a ground wire. When dissimilar metals come into contact with aluminum, a phenomenon called galvanic corrosion occurs. This is a phenomenon in which when the contact interface between dissimilar metals is exposed to a corrosive environment, the metal on the lower potential side is unilaterally and violently corroded. Since the sensor and the ground wire are not made of the same material as the brazing sheet, even if the brazing sheet side is corroded or the sensor and the ground wire side are corroded, the function is lost, which is a problem. Normally, the contact points between the end plate and the ground wire / temperature sensor are connected by screwing, but the screws used at that time are also dissimilar metals. In the configuration of the end plate of the present disclosure, it is possible to embed the contact portion (contact portion) of dissimilar metals in the laminated body, and by making such a configuration, the contact portion Since the (contact portion) is not easily exposed to the corrosive environment, it is possible to construct a highly reliable heat exchanger that can avoid galvanic corrosion of dissimilar metals.

In the embodiment, the structure in which the brazing sheet 10 is provided with the clad layers (12, 13) on both sides of the core material 11 has been described, but the clad layer has functions as a brazing material layer and a sacrificial anticorrosion layer. It suffices to have, and it is sufficient that an aluminum alloy layer containing silicon (Si) and zinc (Zn) is formed on one surface of the core material 11.

As described above, as described in detail in the embodiment, in the heat exchanger of the present disclosure, an end plate having a laminated body structure in which a plurality of brazing sheets are laminated and alloyed is used. In the heat exchanger configured in this way, the end plate has the desired strength, facilitates joining with sleeves such as supply pipes and discharge pipes, and prevents the generation of refrigerant leaks at the joints. Moreover, the laminated structure of the end plates has an excellent corrosion resistance. According to the heat exchanger of the present disclosure and the manufacturing method thereof, the problems in the conventional heat exchanger that the end plates provided on both sides of the laminated plate fins are heavy, difficult to process, and have a problem in corrosiveness are solved. It is a heat exchanger that has a structure that can be reliably joined to sleeves such as supply pipes and discharge pipes, and is provided with an end plate that maintains high rigidity while reducing weight. As a result, in the heat exchanger of the present disclosure and the manufacturing method thereof, it is possible to provide a heat exchanger having high reliability and excellent effect.

Although the present disclosure has been described in the embodiments with some detail, these configurations are examples, and the disclosure content of the embodiments should be changed in the details of the configurations. In the present disclosure, substitutions, combinations, and changes in order of elements in embodiments can be realized without departing from the claimed scope and ideas of the invention.

Since the heat exchanger according to the present disclosure has a structure capable of being compact and lightweight, it can be used for various products and can provide products with high market value.

1 Heat exchanger 2 Plate fin laminate 3 End plate 4 Supply pipe 5 Discharge pipe 10 Brazing sheet 11 Core material 12 1st clad layer 13 2nd clad layer

Claims

A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A heat exchanger provided with a sleeve of an inlet or outlet pipe that is joined to the end plate and communicates with the flow path of the plate fins.
The end plate is a heat exchanger having a laminated structure of a plurality of brazing sheets.
The heat exchanger according to claim 1, wherein the brazing sheet has a first clad layer on at least one surface of a core material.
The heat exchanger according to claim 2, wherein the core material and the material constituting the first clad layer are made of an aluminum alloy, and the first clad layer is made of an aluminum alloy containing silicon and zinc.
The heat exchanger according to claim 2 or 3, wherein the brazing sheet has a second clad layer on the other surface of the core material.
The heat exchanger according to claim 4, wherein the second clad layer is made of an aluminum alloy containing silicon.
The heat exchanger according to any one of claims 2 to 5, wherein the first clad layer has a laminated structure in which an aluminum alloy layer containing silicon is sandwiched between aluminum alloy layers containing zinc.
The heat exchanger according to any one of claims 1 to 6, wherein a part of the laminated body structure of the brazing sheet includes a reinforcing sheet made of another metal different from the brazing sheet.
A plate fin laminate in which plate fins having a flow path are laminated with a gap, and
End plates arranged at both ends of the plate fin laminate in the stacking direction, and
A method of manufacturing a heat exchanger provided with a sleeve of an inlet pipe or an exhaust pipe which is joined to the end plate and communicates with the flow path of the plate fin.
A method for manufacturing a heat exchanger, in which the end plate is formed by laminating a plurality of brazing sheets and alloying them.
The heat exchanger according to claim 8, wherein the brazing sheet has a first clad layer formed on at least one surface of a core material, and the first clad layer is formed of an aluminum alloy containing silicon and zinc. Manufacturing method.
The method for manufacturing a heat exchanger according to claim 9, wherein the first clad layer has a laminated structure in which an aluminum alloy layer containing silicon is sandwiched between aluminum alloy layers containing zinc.
The method for manufacturing a heat exchanger according to claim 9, wherein the brazing sheet has a second clad layer on the other surface of the core material.
The method for manufacturing a heat exchanger according to claim 11, wherein the second clad layer is made of an aluminum alloy containing silicon.
22. How to make a heat exchanger.