JP2004028464A - Heat exchanger and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heat exchanger capable of preventing crushing of a fin while using thin high-temperature conducting material, and its manufacturing method. <P>SOLUTION: In the heat exchanger having fins 111 that are laminated alternately with a plurality of tubes 112 and mutually brazed, one end 111a of each fin 111 in the flow direction of a cooling air is provided with a brazing material 140 to increase thickness of the fin 111. In the specific manufacturing method, a core section 110 in a before-brazing or after-brazing state between each fin 111 and tube 112 is prepared, the end 111a of each fin 111 is coated with the brazing material 140, the core section 110 is supplied to a brazing furnace 200 so that the end 111a coated with the brazing material 140 lies on the lower side, and the brazing material 140 is fused and solidified. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heat exchanger suitable for use as, for example, a radiator for a construction machine and a method for manufacturing the same.
[0002]
[Prior art]
The conventional heat exchanger has fins alternately stacked with a plurality of tubes, and the cooling water flowing in the tubes is cooled by external cooling air. The fin is formed from a thin member, and as a material, a copper material or an aluminum material having excellent thermal conductivity is often used.
[0003]
[Problems to be solved by the invention]
However, when this heat exchanger is used for construction equipment in an environment where sand or small gravel is floating, the sand or small gravel hits the fin together with the cooling air, and the impact causes the end of the fin to collapse. . Then, the ventilation resistance increases due to the collapse of the fins, and the cooling performance is reduced.
[0004]
In order to prevent this, it is conceivable to increase the thickness of the fins or to use iron-based high-strength materials, but this will increase the cost and lower the performance (iron has a higher thermal conductivity than copper and aluminum). Inferior) is inevitable.
[0005]
An object of the present invention is to provide a heat exchanger and a method for manufacturing the same, which can prevent fins from being crushed while using a high heat conductive material with a small thickness in view of the above problems.
[0006]
[Means for Solving the Problems]
The present invention employs the following technical means to achieve the above object.
[0007]
According to the first aspect of the present invention, in the heat exchanger having the fins (111) alternately stacked with the plurality of tubes (112) and brazed to each other, one of the fins (111) in the cooling air flow direction is provided. The end (111a) is characterized in that a brazing material (140) is applied so as to increase the thickness of the fin (111).
[0008]
Thereby, the rigidity of the end portion (111a) can be increased even if the plate thickness and the material of the fin (111) are kept at the originally set specifications, so that the fin (111) is exposed to external impact such as sand or small gravel contained in the cooling air. The end (111a) of (111) can be prevented from being crushed.
[0009]
The invention according to claim 2 is characterized in that the brazing material (140) is the same material used for brazing the fin (111) and the tube (112).
[0010]
Thereby, the brazing material (140) can be simultaneously applied to the end (111a) of the fin (111) under the same temperature condition as the brazing of the original fin (111) and the tube (112).
[0011]
The invention according to claim 3 relates to the method for manufacturing a heat exchanger according to claim 1 or 2, and before or before brazing between the fin (111) and the tube (112). The core part (110) in the state after the contact is prepared, the brazing material (140) is applied to the end part (111a) of the fin (111), and the end part (111a) to which the brazing material (140) is applied is lowered. The brazing material (140) is melted and solidified by putting the core (110) into the brazing furnace (200) so as to be on the side.
[0012]
Accordingly, the brazing material (140) hangs down due to gravity, so that the brazing material (140) can be easily and reliably applied to the end (111a) of the fin (111). Further, since the brazing material (140) is formed in the form of raindrops and solidifies, the turbulence of the cooling air flowing through the fins (111) can be suppressed, and the increase in ventilation resistance can be suppressed.
[0013]
Note that the reference numerals in parentheses of the above means indicate the correspondence with specific means described in the embodiment described later.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
(1st Embodiment)
A first embodiment of the present invention is shown in FIGS. In the first embodiment, the heat exchanger of the present invention is applied to a radiator 100 that cools an engine 10 for a construction machine.
[0015]
The radiator 100 is disposed in the engine room 1 as shown in FIG. 1, and an inlet pipe 102a and an outlet pipe 103a are connected to the engine 10 by rubber hoses 20, respectively. An engine fan 30 is provided on a crankshaft of the engine 10, and cooling air is supplied to the core 110 of the radiator 100 via the shroud 40 by the rotation of the engine fan 30. Each member (described in detail below) of the radiator 100 is made of a copper-based alloy, and is joined to each other by brazing (brazing) using a copper-based brazing material.
[0016]
Next, the overall configuration of the radiator 100 will be described with reference to FIG. The radiator 100 includes a plurality of radiator units 101, a top tank 102, and a bottom tank 103.
[0017]
The radiator unit 101 is a basic part of the radiator 100, and includes a core 110, an upper tank 120, and a lower tank 130. Here, by changing the number of the radiator units 101, it is possible to cope with various engine variations.
[0018]
The core unit 110 is a heat exchange unit that cools the cooling water flowing from the engine 10 and includes fins 111, tubes 112, side plates 113, and a core plate 114.
[0019]
The fins 111 are heat dissipating members that efficiently dissipate the heat of the cooling water to the cooling air side, and are formed in a wavy shape from a thin band plate material. The tube 112 is a member through which cooling water flows, and is formed by bending a thin strip of sheet material so that the cross section becomes flat, and welding the ends thereof. The fins 111 and the tubes 112 are alternately stacked (arranged in the left-right direction in FIG. 2). Of the stacked fins 111, the outermost fin 111 located in the stacking direction is further reinforced. A side plate 113 as a member is provided.
[0020]
The core plate 114 is a shallow box-shaped member having a rim portion with which the opening sides of the upper tank 120 and the lower tank 130 are fitted, and is formed by drawing a flat plate material. At a position corresponding to the longitudinal end of the tube 112 of the core plate 114, a plurality of tube holes are provided, the tube ends are fitted, and the above-described fins 111, tubes 112, side plates 113, and core plate 114 It is brazed at parts that abut each other.
[0021]
The upper tank 120 and the lower tank 130 are box-shaped containers that open on the core plate 114 side, and the openings are fitted to the core plate 114 and brazed. An inflow pipe 121 and an outflow pipe 131 communicating with the insides of the tanks 120 and 130 are provided on the surface on the side opposite to the tube, respectively, and are brazed.
[0022]
A plurality of radiator units 101 formed in this manner are arranged in the direction in which the fins 111 and the tubes 112 are stacked.
[0023]
The top tank 102 and the bottom tank 103 are rectangular parallelepiped containers that extend in the direction in which the radiator units 101 are arranged, and an inlet pipe 102a and an outlet pipe 103a that communicate with the insides of both tanks 102 and 103 are provided on the side surfaces, respectively. Is attached.
[0024]
A plurality of fitting holes 102b and 103b are provided on the radiator unit 101 side surfaces of the top tank 102 and the bottom tank 103, respectively, and the inflow pipe 121 and the outflow pipe 131 of each radiator unit 101 are fitted. Then, the top tank 102 and the bottom tank 103 are brazed to the upper tank 120 and the lower tank 130, respectively, to form the radiator 100.
[0025]
As a feature of the present invention, a brazing material 140 is provided at the end 111a of the fin 111 of the radiator unit 101, and the details thereof will be described below with reference to FIG.
[0026]
The end 111a of the fin 111 is the end in the direction in which the cooling air flows to the fin 111, and here, is on the cooling air inflow side. The end portion 111a is provided with a brazing material 140 so as to increase the thickness of the fin 111. The brazing material 140 is the same as the brazing material used when brazing the components of the radiator 100.
[0027]
The brazing material 140 is specifically applied to the fins 111 by the method shown in FIG. First, as shown in FIG. 4A, an assembly as the radiator 100 is formed by assembling the above members, fitting, caulking, fixing a jig, and the like, and the surface (fin) of the core portion 110 of the assembly is formed. A paste brazing material (140) containing a brazing material powder and a binder is applied to the end 111a) of 111.
[0028]
Then, as shown in FIG. 4B, the assembly (radiator 100) is put into the brazing furnace 200 such that the end 111a to which the paste brazing material (140) is applied is on the lower side, and The brazing paste (140) is melted and solidified simultaneously with the integral brazing.
[0029]
Next, the operation of the radiator 100 based on the above-described configuration and manufacturing method and the operation and effect thereof will be described.
[0030]
The cooling water of the engine 10 flowing into the top tank 102 from the inlet pipe 102a further flows into the plurality of radiator units 101 through the inlet pipe 121. Then, it is cooled by heat exchange with cooling air while flowing through the plurality of tubes 112. At this time, the heat exchange is promoted by the fins 111. Then, the cooling water is collected in the bottom tank 103 through the outflow pipe 131, flows out of the outlet pipe 103a, and returns to the engine 10.
[0031]
By the way, under the environmental conditions in which the construction machine is used, the sand, small gravel and the like wound up in the air are supplied to the radiator 100 together with the cooling air. In the present invention, since the brazing material 140 is provided at the end 111a of the fin 111 on the cooling air inflow side, the rigidity of the end 111a is increased even if the thickness and the material of the fin 111 remain as originally set. Thus, the end 111a of the fin 111 can be prevented from being crushed by sand or small gravel contained in the cooling air. Therefore, it is possible to prevent the cooling performance from lowering due to an increase in ventilation resistance in the core portion 110.
[0032]
When the brazing material 140 is applied to the end 111a of the fin 111, as described with reference to FIG. 4, the brazing material 140 hangs down by gravity, so that the end 111a of the fin 111 The brazing material 140 can be easily and reliably applied. Further, since the brazing material 140 is formed in the form of raindrops and solidifies, the turbulence of the cooling air flowing through the fins 111 can be suppressed, and the increase in the ventilation resistance can be suppressed.
[0033]
Further, since the brazing material 140 is made of the same material as that used for brazing the members (the fins 111 and the tubes 112) constituting the radiator 100, the end of the fin 111 is simultaneously formed under the same temperature conditions as the brazing of the members. The brazing material 140 can be applied to the portion 111a.
[0034]
(Other embodiments)
In the first embodiment, the brazing material 140 is described to be performed simultaneously with the integral brazing of the members of the radiator 100. However, the present invention is not limited to this, and the paste brazing material ( 140) may be applied and melted and solidified on the end 111a of the fin 111. In this case, it is preferable that the brazing material 140 having a lower melting point than that of the brazing material for the radiator 100 be selected so as to avoid secondary melting of brazing on the radiator 100 side.
[0035]
The material of each member constituting the radiator 100 is not limited to a copper-based material, but may be a material using a material such as aluminum or stainless steel.
[0036]
Further, the present invention is not limited to a radiator for a construction machine, and may be applied to a radiator for another four-wheeled vehicle. In a four-wheeled vehicle, dirt and dust may adhere to the fins 111 in the use environment, and when removing the fins, when cleaning with high-pressure water is performed, the effect on the fin collapse may be exerted. it can.
[0037]
Further, instead of the radiator 100, another heat exchanger may be applied to an intercooler, a condenser, or the like.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a state in which a radiator is mounted on a construction machine.
FIG. 2 is an exploded perspective view showing the entire radiator.
FIG. 3 is a sectional view showing an AA section in FIG. 2;
FIGS. 4A and 4B are process charts showing a brazing material application step and a brazing step during the manufacture of a radiator.
[Explanation of symbols]
100 radiator (heat exchanger)
101 radiator unit (heat exchanger)
110 Core part 111 Fin 111a End part 112 Tube 140 Brazing material 200 Brazing furnace (brazing furnace)

Claims (3)

In a heat exchanger having fins (111) alternately stacked with a plurality of tubes (112) and brazed to each other,
The heat exchange characterized in that a brazing material (140) is applied to one end (111a) of the fin (111) in the direction of cooling air flow so as to increase the thickness of the fin (111). vessel. The heat exchanger according to claim 1, wherein the brazing material (140) is the same material used for brazing the fin (111) and the tube (112). The fin (111) has a core portion (110) in which tubes (112) are alternately stacked, and the fin (111) is attached to one end (111a) of the fin (111) in the cooling air flow direction. 111) A method of manufacturing a heat exchanger for applying a brazing filler metal (140) so as to increase the thickness of the plate.
Prepare the core part (110) before or after brazing between the fin (111) and the tube (112),
Applying the brazing material (140) to the end (111a) of the fin (111);
The core part (110) is put into the brazing furnace (200) such that the end part (111a) coated with the brazing material (140) is on the lower side, and the brazing material (140) is melted and solidified. A method of manufacturing a heat exchanger.

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