JP3596046B2 - Stacked heat exchanger - Google Patents

Description

【００２６】
【表２】

【００２７】
【表３】

【００２８】
上述のように、冷媒冷媒熱交換部Ａでは、単位空間容積当りのろう材１３ｂ中のＭｇ含有量を少なくして適正化を図ったことにより、それまでのろう付け不良が改善されて、冷媒空気熱交換部Ｂと同様に良好なろう付けを得ることができた。
【図面の簡単な説明】
【図１】冷媒蒸発器の斜視図である。
【図２】冷媒蒸発器の分解斜視図である。
【図３】クラッド材の断面図である。
【図４】コア部と冷媒冷媒熱交換部との単位体積当りの重量を比較したグラフである。
【図５】コア部と冷媒冷媒熱交換部との単位空間容積当りのＭｇ量を比較したグラフである。
【符号の説明】
１ 冷媒蒸発器（積層型熱交換器）
６ 成形プレート（冷媒冷媒熱交換部）
７ａ 絞り部
８ 成形プレート（冷媒空気熱交換部）
１１ 入口流路
１２ 出口流路
１３ａ 芯材
１３ｂ ろう材
Ａ 冷媒冷媒熱交換部（流体流体熱交換部）
Ｂ 冷媒空気熱交換部（流体空気熱交換部）[0001]
[Industrial applications]
The present invention relates to a stacked heat exchanger including a fluid-fluid heat exchanger and a fluid-air heat exchanger, and more particularly, to the Mg content of each forming plate constituting the fluid-fluid heat exchanger and the fluid-air heat exchanger. About.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a laminated refrigerant evaporator used for a vehicle refrigeration cycle or the like, a refrigerant flowing into an inlet tank is reduced in dryness to be a liquid single-phase refrigerant, and is distributed from the inlet tank to each refrigerant passage. It is known to improve the performance by equalizing the amount of refrigerant.
[0003]
Therefore, for example, in Japanese Patent Application Laid-Open No. 5-196321, an inlet passage communicating with the inlet tank via the throttle portion and an outlet passage communicating with the outlet tank are formed adjacent to each other, and the refrigerant flowing through the inlet passage and the outlet passage are formed. There has been proposed a laminated refrigerant evaporator provided with a refrigerant-refrigerant heat exchanging unit for exchanging heat with a refrigerant flowing through the evaporator. In the refrigerant-refrigerant heat exchanging section, the refrigerant flowing through the outlet passage is depressurized at the throttle portion and has a lower temperature than the refrigerant flowing through the inlet passage. The refrigerant flowing through the passage is heated to increase the degree of superheat.
[0004]
[Problems to be solved by the invention]
The above-mentioned laminated refrigerant evaporator is manufactured by vacuum-brazing in the same furnace after temporarily assembling a core part (a part for performing heat exchange between refrigerant and air) and a refrigerant refrigerant heat exchange part integrally. You. In this vacuum brazing, the brazing property is influenced by the amount of Mg contained in the brazing material of each forming plate constituting the core portion and the refrigerant / heat exchanger. The forming plate is generally composed of an aluminum core material and a brazing material joined to both sides or one surface of the core material. The brazing material is made of Mg to break an oxide film formed on the surface of the aluminum. Is contained.
[0005]
However, in the refrigerant evaporator provided with the above-described refrigerant-refrigerant heat exchange part, the weight per unit volume differs between the core part and the refrigerant-refrigerant heat exchange part as follows.
The core portion is formed by joining two molded plates to form one tube and alternately stacking the tubes and fins. On the other hand, the refrigerant-refrigerant heat exchanging section is configured by laminating a plurality of molding plates alone without interposing fins unlike the core section. Accordingly, the weight per unit volume (heat capacity) of the refrigerant heat exchange section is twice or more heavier than the core section (see FIG. 4).
[0006]
As a result, the amount of Mg per unit space volume is larger in the refrigerant heat exchange section than in the core section (see FIG. 5). That is, if the amount of Mg per unit space volume on the core portion side is appropriate, the Mg amount on the refrigerant heat exchange portion side is in a supersaturated state. For this reason, when vacuum brazing is performed in the same furnace, the diffusion of Mg into the furnace is suppressed on the refrigerant heat exchange part side and the breakdown of the oxide film does not proceed. As a result, there arises a problem that the brazing property deteriorates.
[0007]
The present invention has been made based on the above circumstances, and an object of the present invention is to improve the brazing property of a laminated heat exchanger manufactured by integral brazing.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, in claim 1, an inlet channel and an outlet channel formed adjacent to each other are provided, and a fluid flowing through the inlet channel and a fluid flowing through the outlet channel are provided. A fluid-fluid heat exchange unit that performs heat exchange between the fluid passage and an upstream side that communicates with the inlet channel via a throttle unit, and a downstream side that has a plurality of fluid channels that communicates with the outlet channel. A fluid-air heat exchanging unit for exchanging heat between the fluid flowing through the fluid flow path and the air, wherein the fluid-fluid heat exchanging unit and the fluid-air heat exchanging unit are each provided with a core, In a laminated heat exchanger configured by laminating a plurality of forming plates made of brazing material clad on one side,
The technical means is such that the forming plate constituting the fluid-fluid heat exchanging section has a smaller amount of Mg contained in the brazing material than the forming plate constituting the fluid-air heat exchanging section.
[0009]
According to a second aspect, in the laminated heat exchanger according to the first aspect,
The forming plate forming the fluid-fluid heat exchanging part has a Mg content of 0.8% by weight in the brazing material, and the forming plate forming the fluid-air heat exchanging part has a Mg content of 1 in the brazing material. .2% by weight.
[0010]
[Action and effect of the invention]
In the stacked heat exchanger of the present invention having the above-described configuration, the Mg content in the brazing material is smaller in the forming plate forming the fluid-fluid heat exchange section than in the forming plate forming the fluid-air heat exchange section. Thereby, the difference in the amount of Mg per unit space volume between the fluid air heat exchange unit and the fluid fluid heat exchange unit is reduced. That is, similarly to the fluid air heat exchange unit, the amount of Mg per unit space volume of the fluid fluid heat exchange unit can be optimized, and good brazing properties can be obtained.
[0011]
【Example】
Next, an embodiment of the laminated heat exchanger of the present invention will be described.
FIG. 1 is a perspective view of a laminated heat exchanger used as a refrigerant evaporator, and FIG. 2 is an exploded perspective view of the refrigerant evaporator.
The refrigerant evaporator 1 of this embodiment is used in a vehicle refrigeration cycle, and is interposed between an expansion valve 2 (see FIG. 2) and a refrigerant compressor (not shown).
[0012]
This refrigerant evaporator 1 is provided with a refrigerant-refrigerant heat exchange part A for exchanging heat between an inflow refrigerant and an outflow refrigerant, and a refrigerant-air heat exchange part B for exchanging heat between refrigerant and air. As shown in FIG. 2, a joint block 3 for connecting a refrigerant pipe (not shown), a set of end plates 4 and 5, a plurality of forming plates 6, and a restricting portion 7a constituting a refrigerant / refrigerant heat exchange section A (FIG. 2), a plurality of forming plates 8 and end plates 9 constituting the refrigerant / air heat exchange section B, and corrugated fins 10 used in the refrigerant / air heat exchange section B.
[0013]
The joint block 3 is fixed (brazed) to the upper end of one of the end plates 4 of the refrigerant-refrigerant heat exchange section A, and is connected to the inlet port 3a to which the expansion valve 2 is connected and the outlet port 3b to be connected to the refrigerant compressor. , And a bypass port 3c (to be described later).
[0014]
As shown in FIG. 2, the refrigerant heat exchange unit A is configured by stacking (stacking) a plurality of forming plates 6 between two end plates 4 and 5, and forming two adjacent forming plates. The inlet flow paths 11 and the outlet flow paths 12 are alternately formed between 6, 6 (see FIG. 1).
Each inlet channel 11 formed between the two forming plates 6, 6 communicates through circular inlet holes 6 a formed at both ends of the forming plate 6 and communicates with the inlet port 3 a of the joint block 3. . The outlet channels 12 formed between the two forming plates 6 communicate with each other through oval outlet holes 6 b formed at both ends of the forming plate 6, and the outlet port of the joint block 3. 3b.
[0015]
The capillary plate 7 is overlapped with the other end plate 5 of the refrigerant / heat exchanger A to form a throttle portion 7a (see FIG. 2) forming a capillary tube with the end plate 5.
[0016]
The refrigerant-air heat exchanging section B is configured by alternately arranging flat tubes 80 and corrugated fins 10 formed by the two forming plates 8 between the capillary plate 7 and the end plate 9.
The flat tube 80 is provided with an inlet tank (not shown) and an outlet tank 81 at its lower end side by side, and has a refrigerant passage (fluid flow path of the present invention / shown in the present invention) communicating the inlet tank and the outlet tank 81 inside. No) is formed. Each of the flat tubes 80 is provided such that the inlet tanks and the outlet tanks 81 communicate with each other in the stacking direction. Each of the inlet tanks communicates with the inlet channel 11 of the refrigerant / refrigerant heat exchange unit A through the throttle unit 7a. The tank 81 communicates with the outlet channel 12 of the refrigerant heat exchange unit A.
[0017]
The refrigerant is introduced into the bypass port 3c provided in the joint block 3 when the condensation pressure of a refrigerant condenser (not shown) is low (for example, 6 kg / cm ² · G) in winter or the like. The refrigerant that has flowed in from the bypass port 3c passes through the communication holes 6c provided in each forming plate 6, and is guided directly to the inlet tank, bypassing the throttle portion 7a.
[0018]
Next, the operation of the refrigerant evaporator 1 of the present embodiment will be described.
The refrigerant sent from the expansion valve 2 flows in the order of the inlet port 3a → the inlet channel 11 → the throttle unit 7a → the inlet tank → the refrigerant passage → the outlet tank 81 → the outlet channel 12 → the outlet port 3b.
[0019]
Here, the temperature of the refrigerant flowing from the inlet flow path 11 into the inlet tank through the throttle portion 7a becomes lower by the amount of pressure reduced by the throttle portion 7a. Therefore, in the refrigerant-refrigerant heat exchanging section A, the refrigerant flowing through the inlet flow path 11 is cooled by heat exchange between the refrigerant flowing through the inlet flow path 11 and the refrigerant flowing through the outlet flow path 12, and the liquid-single phase progresses. As a result, the uniformity of the amount of the refrigerant distributed from the inlet tank to each refrigerant passage can be promoted, so that the performance of the refrigerant evaporator 1 can be improved.
[0020]
The refrigerant evaporator 1 of the present embodiment is manufactured by vacuum brazing in a furnace after assembling the entire shape. FIG. 3 shows the materials of the plates 4 to 6 constituting the refrigerant / refrigerant heat exchange unit A, the capillary plate 7 forming the throttle unit 7a, and the plates 8 and 9 constituting the refrigerant / air heat exchange unit B. As described above, the clad material 13 in which the brazing material 13b equivalent to A4104 is pressed (cladded) on both surfaces (or one surface) of the core material 13a equivalent to A3003.
[0021]
However, the clad material 13 used for the refrigerant heat exchange unit A and the clad material 13 used for the refrigerant air heat exchange unit B differ in the amount of Mg per unit space contained in the brazing material 13b, The clad material 13 used for the refrigerant-refrigerant heat exchange unit A has a lower Mg content in the brazing material 13b than the clad material 13 used for the refrigerant-air heat exchange unit B.
[0022]
This is because, when comparing the refrigerant refrigerant heat exchange part A and the refrigerant air heat exchange part B, the amount of Mg per unit space volume of the refrigerant refrigerant heat exchange part A is larger than that of the refrigerant air heat exchange part B, and brazing is performed. This is because the cause of the failure is to reduce the amount of Mg per unit space volume of the refrigerant heat exchange unit A to improve the brazing property.
[0023]
Therefore, a brazing experiment was carried out by appropriately changing the Mg content in the brazing material 13b to find the optimum Mg content. As a result, in the clad material 13 used in the refrigerant air heat exchange part B, the Mg content in the brazing material 13b is set to 1.2% by weight, and in the clad material 13 used in the refrigerant refrigerant heat exchange part A, The Mg content in the material 13b was set to 0.8% by weight.
[0024]
The components of the clad material 13 used in this example are shown in the following table.
However, Table 1 is a component table of the core material 13a (A3003) (the same is applied to the refrigerant / refrigerant heat exchange part A and the refrigerant / air heat exchange part B), and Table 2 is a brazing material 13 for the refrigerant / refrigerant heat exchange part A. Material 13b (A4104) component table, and Table 3 is a brazing material 13b (A4104) component table of the clad material 13 used in the refrigerant air heat exchange unit B.
[0025]
[Table 1]

[0026]
[Table 2]

[0027]
[Table 3]

[0028]
As described above, in the refrigerant-refrigerant heat exchange section A, the brazing material 13b per unit space volume is reduced and optimized by reducing the Mg content. As in the case of the air heat exchange section B, good brazing could be obtained.
[Brief description of the drawings]
FIG. 1 is a perspective view of a refrigerant evaporator.
FIG. 2 is an exploded perspective view of a refrigerant evaporator.
FIG. 3 is a sectional view of a clad material.
FIG. 4 is a graph comparing the weight per unit volume between a core part and a refrigerant heat exchange part.
FIG. 5 is a graph comparing the amount of Mg per unit space volume between a core part and a refrigerant / refrigerant heat exchange part.
[Explanation of symbols]
1 Refrigerant evaporator (laminated heat exchanger)
6 Forming plate (refrigerant heat exchange unit)
7a Restrictor 8 Forming plate (refrigerant air heat exchanger)
11 inlet flow path 12 outlet flow path 13a core material 13b brazing material A refrigerant refrigerant heat exchange unit (fluid fluid heat exchange unit)
B Refrigerant air heat exchanger (fluid air heat exchanger)

Claims (2)

A fluid-fluid heat exchange unit having an inlet channel and an outlet channel formed adjacent to each other, and performing heat exchange between a fluid flowing through the inlet channel and a fluid flowing through the outlet channel; The fluid air has a plurality of fluid passages, the side of which communicates with the inlet channel via a throttle, and the downstream side of which communicates with the outlet channel, and which performs heat exchange between the fluid flowing through the fluid channel and air. With a heat exchange section,
The fluid heat exchange section and the fluid air heat exchange section are each a stacked heat exchanger formed by stacking a plurality of forming plates each made of a core material and a brazing material clad on both sides or one side of the core material. At
A forming plate forming the fluid-fluid heat exchanging portion, wherein the amount of Mg contained in the brazing material is reduced with respect to a forming plate forming the fluid-air heat exchanging portion; . The stacked heat exchanger according to claim 1,
The forming plate constituting the fluid-fluid heat exchange section has a Mg content of 0.8% by weight of the brazing material,
The forming plate constituting the fluid-air heat exchange unit has a Mg content of 1.2% by weight in the brazing filler metal, wherein the brazing material has a Mg content of 1.2% by weight.

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