JPS63194191A - Plate fin type heat exchanger and manufacture thereof - Google Patents

Abstract

PURPOSE:To reduce the amount of remaining drain, by a method wherein hydrophilic films are formed on the whole surfaces of respective fin members while water repellent films are formed on at least the lower surfaces of respective flared rims. CONSTITUTION:A plate fin type heat exchanger consists of plate type fin members 1, provided with penetrating holes 2 which are provided with flared type swelled rims 4 therearound, and refrigerant pipelines 3, penetrated through the penetrating holes 2 of the plurality of fin members 1. Hydrophilic films are formed on the whole surfaces of respective fin members 1 substantially and water repellent films are formed on at least the lower surfaces of respective flared rims 4. The water repellent film is formed on the lower surfaces of the flared rims 4 of respective fin members 1, therefore, water drips, remaining in a size balancing with an attracting force effected from the surface of the flared rim, reduce their attracting force largely by the water repellent films whereby the drips drop under their own weights. Accordingly, the remaining of water drips may be eliminated and the amount of remaining drain may be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a plate-fin type heat exchanger used in air conditioners and the like, and a method for manufacturing the same.

(Prior Art) When a plate-fin type heat exchanger in an air conditioner or the like acts as an evaporator, moisture in the atmosphere condenses and becomes water droplets that adhere to the fin surface.

If such water droplets, so-called condensate, remain on the ventilation path of the heat exchanger, the heat exchange characteristics will be impaired, so it is necessary to quickly drain the generated condensate. For this purpose, for example,
No. 185996 discloses that a hydrophilic film is formed on the entire surface of a fin member constituting a plate-fin type heat exchanger,
This reduces the amount of drain remaining on the surface of the fin member. FIG. 4 shows a schematic cross-sectional view of the plate-fin type heat exchanger, and as shown in the figure, each fin member 41 made of a thin aluminum plate is erected at a predetermined distance from each other. By forming a hydrophilic treatment film on their surfaces, the generated drainage will not accumulate in a so-called bridge state as shown in (A) in the figure.
The drain will quickly flow down along the vertical plane, making it possible to reduce the amount of residual drain.

(Problem to be Solved by the Invention) As mentioned above, drain adhering to the surface of the fins installed approximately vertically flows down the surface quickly due to the hydrophilic nature of the surface. However, in the plate-fin type heat exchanger as described above, as shown in FIG. There is a problem in that drain generated and deposited in the horizontal portions between these fin members 41 tends to remain without being drained. In this horizontal part, the refrigerant pipe 4
A bulging edge 44 (hereinafter referred to as a flare portion) protruding from the periphery of the through hole 43 of each fin member 41 in a flare shape is positioned so as to surround the outer periphery of the fin member 2. Drain generated in the outer circumferential cylindrical flare portion 44 remains in the form of water droplets below it as shown in FIG. 4 (B). There is an adverse effect of the hydrophilic treatment in that the higher the hydrophilicity of the flared portion 44, the larger the water droplets become.As the drain remains along the horizontally arranged refrigerant pipe 42, There was a problem that ventilation resistance increased and heat exchange efficiency decreased. In particular, if such residual condensate freezes, a large amount of heat for defrosting will be consumed during the defrosting operation, which will lengthen the defrost time and impair air conditioning comfort. That was the result.

This invention was made to solve the above-mentioned conventional problems, and its first purpose is to provide a plate-fin type heat exchanger that can also reduce the amount of residual drain generated in the horizontal section as described above. A second object is to provide a method for manufacturing a plate-fin type heat exchanger that can more efficiently manufacture a heat exchanger that can reduce the amount of residual drain as described above.

(Means for Solving the Problems) Therefore, in the plate-fin type heat exchanger of the first invention, the plate-like fin member 1 is provided with a through hole 2, and a flared bulge edge 4 is provided on the periphery of the through hole. Form and refrigerant piping 3
is inserted into each of the through holes 2 of a plurality of fin members 1, and a hydrophilic film is formed on substantially the entire surface of each of the fin members 1, and each of the bulged edges 4 A water-repellent film is formed on at least the lower surface of.

The method for manufacturing a plate-fin type heat exchanger according to the second invention also includes the step of forming a water-repellent film on a predetermined region of the plate-shaped fin member 1, and the step of forming a through hole having a flared bulge edge 4 on the periphery. 2 at a position that includes the water-repellent film formation region in at least a portion of the bulging edge 4; a step of inserting the refrigerant pipe 3 into the through hole 2; and before or after any of the above steps. and forming a hydrophilic film on the surface of the fin member 1.

(Function) 1 In the first invention, since a water-repellent film is formed on the lower surface of the bulge edge 4 of each fin member 1, the adsorption force that conventionally acts from the bulge edge surface at that position is reduced. The remaining water droplets with a size proportional to the size of the water droplets will fall due to their own weight since the adsorption force will be very small due to the water repellent film. Therefore, water droplets do not remain as in the conventional case, and the amount of residual drain is reduced.

Further, in the second invention, when manufacturing a plate-fin heat exchanger having a water-repellent film locally on the surface of the bulging edge 4 as described above, when the fin member 1 is in a flat plate state, the water-repellent film is applied. , and then a flared bulge edge 4
Since the through-hole 2 having a diameter is bored, each process involves machining a flat plate as the target material, and therefore positioning and machining in each process are easy, and therefore mass production of the fin member 1 as described above is possible. possible, more efficient manufacturing.

(Embodiments) Next, specific embodiments of the present invention will be described in detail with reference to the drawings.

First, the manufacturing process of a fin member constituting a plate-fin type heat exchanger according to an embodiment of the present invention will be explained based on FIGS. 2(a) to 2(d). FIG. 1A shows an aluminum material 10 that constitutes the fin member 1. As shown in FIG. The hoop-shaped aluminum vi10 is straightened into a flat plate shape and is continuously supplied to the film forming process shown in FIG. 2(b). In this film forming process, first, by printing, for example, a silicone polymer or fluorine-based water-repellent paint is applied to a predetermined diagonal area S as shown in the figure 0)), that is, in the feeding direction of the aluminum material. It is applied continuously in a plurality of line-shaped areas parallel to each other at regular intervals. Thereafter, it is baked at a predetermined temperature through a dryer or the like to form a water-repellent film with a thickness of 2 to 50 μm. Next, a hydrophilic paint containing, for example, an acrylic resin, a surfactant, synthetic silica, etc., is applied to the area U including the entire back surface other than the shaded area in FIG. 2(b), and baked in the same manner as above. , forming a hydrophilic film of 2 to 50 μm. Thereafter, as shown in FIG. 2(C), through holes 2 for inserting refrigerant pipes are bored at predetermined intervals. At this time, as will be described later, a flared bulge edge is formed on the periphery of the through hole 2 by drawing in a step before or after the step of drilling the through hole 2. The center of each of the through holes 2 is made to coincide with the center of the line of the water repellent film. Thereafter, by cutting along the division lines 1 and f2 shown in FIG. 2(C), the fin member 1 as shown in FIG. 2(d) is obtained.

A plate-fin type heat exchanger as shown in FIG. 1 is constructed by stacking a large number of fin members 1 thus formed and inserting refrigerant pipes 3 into through holes 2. At this time, the water-repellent film surface S, as shown in FIG. 2(d),
It is a line extending vertically including the center of each through hole 2, and therefore, a flared bulge edge (hereinafter referred to as , referred to as the flared portion) 4, the above-mentioned water-repellent coating is formed on the upper and lower portions of the cylindrical outer circumferential surface. This flare portion 4 maintains the spacing between the fin members 1 in the assembled state shown in FIG.

In the plate-fin type heat exchanger configured as described above, when it is used as an evaporator, water droplets that adhere to the fin member l due to moisture in the atmosphere condensing, so-called drain, are treated as follows. It has a powerful effect. First, since a hydrophilic film is formed on the vertical arrangement surface of the fin member 1, the drainage generated in this area does not become large water droplets or remain in a bridge state between adjacent fin members, and is As in the conventional example, it quickly flows down along the vertical plane. In the above configuration, the drain adhering to the flare portion 4 in the horizontally disposed state also drips quickly without becoming a large water droplet. In other words, in the conventional example in which the flare portions 4 were also subjected to hydrophilic treatment, the drain collected at the lower position of each flare portion and remained as water droplets, but the size of the water droplets was It depends on the magnitude of the adsorption force acting on the water droplets from the surface of the flared portion. When hydrophilic treatment has been performed, the adsorption force is large, and therefore, the water stays in the form of large water droplets. However, in the above embodiment, a water-repellent film is formed on the flared portion 4, especially on the lower side where water droplets accumulate, and therefore the adsorption force is significantly reduced, so that large water droplets remain in that position. This is no longer possible, and the drain falls due to its own weight.

For these reasons, in the plate-fin type heat exchanger in the above embodiment, the amount of residual drain is reduced, and therefore the increase in ventilation resistance in the heat exchanger is suppressed, so that the heat exchange performance can be maintained and improved. becomes possible. For example, in a separate air conditioner, during heating operation in winter, frost forms on the heat exchanger in the outdoor unit that acts as an evaporator, and a defrost operation is required to remove this frost. In the heat exchanger, if the condensate attached to the flare section along the refrigerant piping freezes,
A large amount of defrosting heat was required to thaw this. In the embodiment described above, residual water in the flare portion 4 is suppressed, so the amount of heat required for defrosting is reduced, and as a result, defrosting is completed in a short time, improving air conditioning comfort.

The above embodiment includes both the first invention and the second invention, but the characteristic part of the first invention is that the fin members constituting the plate-fin heat exchanger are arranged in a substantially vertical state. In addition to forming a hydrophilic film on the surface of the flare part, which is arranged horizontally and has a cylindrical outer periphery, a water-repellent film is formed on at least the lower surface of the flare part. This allows rapid draining of condensate throughout the heat exchanger.

Further, the characteristic part of the second invention is that when forming a water-repellent film locally on the surface of the flared portion that bulges out from the main plane of the fin member having the flared portion as described above, first, the water-repellent film is formed in a flat plate state. The point is that a water-based film is formed, and then bulging and hole processing are performed.As a result, the target materials in each process are both flat plates, and mutual positioning is easy and efficient.
In addition, we can mass produce fin parts with high processing precision.
By assembling these fin members, a plate-fin type heat exchanger with excellent performance can be manufactured at low cost.

In addition, in the above example, when forming a water-repellent film, an example is explained in which the paint is applied continuously in a line shape, which makes the application process easier and the positioning with the through hole easier. I gave an example, but for example,
As shown in Figure (a), a region Sa including the entire flare portion 4,
Alternatively, as shown in FIG. 3, shape regions corresponding to the lower regions sb of the flare portion 4 are determined in advance for the state of the flat material, and spaced apart in the material feeding direction at these positions. It is also possible to apply a t3 water-based paint.

Further, in the above embodiments, the step of forming a hydrophilic film was explained after forming the water-repellent film, but these steps may be interchanged, and the step of forming a hydrophilic film can be replaced with, for example, a step of forming a hydrophilic film. When a coating film is formed using a turbid aqueous solution of the coating material, even if the entire fin member is immersed in the solution, water will be repelled from the area where the water-repellent coating has been previously formed. By doing so, it is possible to prevent the hydrophilic film from being selectively formed on the water-repellent film, so that it is possible to prevent the hydrophilic film from being selectively formed on the water-repellent film. It is also possible to form a hydrophilic film by.

(Effects of the Invention) In the first invention, a hydrophilic film is formed on almost the entire surface of the fin member, and a small amount of repellent (at least on the lower side) is formed on the bulge edge around the through hole through which the refrigerant pipe is inserted. Since it forms an aqueous film, even on the above-mentioned bulging edge, which is arranged in a substantially horizontal state, the weight of the condensate generated on the surface is promoted, and the amount of residual condensate can be reduced. .

Further, in the second invention, when forming a water-repellent film locally on the bulge edge protruding from the main plane of the fin member, the water-repellent film is first formed on the flat plate material, and then the water-repellent film is formed on the bulge edge as described above. By performing edge and hole machining, the target materials in each process are both flat plates, so positioning and processing operations in each process are facilitated.
It becomes possible to manufacture fins and members with excellent mass productivity, and therefore, using such fin members, a heat exchanger with excellent drain drainage performance can be manufactured at a lower cost and more efficiently.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view showing a cross section of a main part of a plate-fin type heat exchanger according to an embodiment of the first invention, and FIG.
Figures (a) to (b) are diagrams showing the manufacturing process of a fin member showing one embodiment of the second invention, and Figures 3 (a) and b) are fin members showing other embodiments of the invention, respectively. FIG. 4 is a schematic diagram illustrating the state of drain adhesion in a conventional heat exchanger. DESCRIPTION OF SYMBOLS 1... Fin member, 2... Through hole, 3... Refrigerant piping, 4... Flare part (bulging edge). Patent applicant: Daikin Industries, Ltd.
−− Agent Masahiro Nishimori. Figure 1

Claims (2)

[Claims] 1. A through hole (2) is provided in the plate-like fin member (1), and a flared bulging edge (4) is formed at the periphery of the through hole, and the refrigerant pipe (3) is connected to the plurality of fin members (1).
A plate-fin type heat exchanger that is inserted through each through hole (2) of the fin member (1), in which a hydrophilic film is formed on substantially the entire surface of each of the fin members (1), and a hydrophilic film is formed on substantially the entire surface of each of the fin members (1), and A plate-fin type heat exchanger, characterized in that a water-repellent film is formed on at least the lower surface. 2. A process of forming a water-repellent film on a predetermined area of the plate-shaped fin member (1), and forming a flared bulge edge (4) on the periphery.
) at a position that includes the water-repellent film formation region on at least a portion of the bulging edge (4); and a step of drilling a refrigerant pipe (3) in the through hole (2). A method for producing a plate-fin type heat exchanger, comprising the steps of: inserting the fin member (1) through the fin member (1); and forming a hydrophilic film on the surface of the fin member (1) before or after any of the above steps.