JP2000234883A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat exchanger comprising flat tubes excellent in corrosion resistance and durability and drainage performance is enhanced at the core section where the component members can be integrated surely by brazing in furnace. SOLUTION: A core section comprises a large number of plate fins 1,... arranged in vertical state, and flat tubes 3,... arranged vertically in multi-stage while being fitted, in horizontal state, in cuts 2 recessed in the widthwise direction from one side end of the plate fins 1,.... The flat tube 3 is fitted in the cut 2 through a brazing sheet cover member 6A having a substantially U-shaped side view and jointed integrally with the plate fins 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger used for various types of air conditioners, such as condensers for car air conditioners and evaporators, and refrigerators.

[0002]

2. Description of the Related Art As a heat exchanger used for a condenser or an evaporator for a car air conditioner, as shown in FIG. 5, a header (11A) (11B) comprising a pair of round pipes facing each other at a required interval. A number of flat tubes (12) each having both ends connected to both headers (11A) (11B) are arranged in parallel with each other via corrugated fins (13) to form a core portion (14). , Both headers (11A)
The partition (15) in the (11B) is set so that the heat exchange medium flowing from the inlet (16) flows in a meandering manner through the core (14) through the tubes (12) to the outlet (17). What has been done is widely used. In addition, without using the pair of headers, a serpentine tubing tube bent into a shape in which one flat tube is folded at a fixed length is used, and corrugated fins are interposed between linear portions arranged in multiple stages. In some cases, a similar core portion is formed.

[0003] The corrugated fins used in the cores of these heat exchangers increase the heat exchange efficiency by increasing the contact area with air, but have a meandering form so as to increase the heat exchange efficiency. The type in which the flat tubes (12) ... are horizontal as shown in Fig. 6 (a) with the heat exchanger installed due to poor drainage of the condensed water generated by the replacement, and Fig. 6 (b)
In any of the types in which the flat tubes (12)... Are vertical, water droplets (d) tend to accumulate between the fins (13) as shown in FIG. 12) There was a drawback that corrosion deterioration of ... was accelerated.

On the other hand, as shown in FIGS. 4 (a) and 4 (b), a plurality of flat plate fins (1)... 1) A heat exchange in which a core portion (10) is constituted by a flat tube (3) which is horizontally fitted into a notch portion (2) which is recessed in a width direction from one side end and which is arranged in upper and lower tiers. (For example, JP-A-6-50688), both sides of a vertical plate fin (1) are flat tubes (3).
Since it has a shape that protrudes forward and backward, water droplets easily fall along the protruding both sides, and there is an advantage that drainage of dew condensation water is excellent. The plate fin (1) and the flat tube (3) are not shown in the middle part of the core (10) in FIG. In addition, FIG.
(4A) and (4B) are vertically arranged round pipe headers, (5A) is an inlet for the heat exchange medium, (5B) is the outlet, and (1a) is a plate in FIG. The fins (1) are ridges formed by louver processing.

[0005]

However, the above plate fins (1) and flat tubes (3) are used.
Also in the heat exchanger having the core portion (10), it is inevitable that a certain amount of dew water is always attached to the surface of the flat tubes (3). Corrosion degradation of... Proceeds. Also,
In the configuration of the core part (10), the plate fin (1)
And the flat tube (3) must be integrally joined by brazing in a furnace. When a brazing sheet is used as the plate fin (1) for this joining,
In the louver processing which is generally performed in order to increase the fin strength due to the decrease in the fin strength due to the reduction in wall thickness due to the melting of the brazing material at the time of furnace brazing,
There was also a drawback that the mold used was liable to wear and break.

SUMMARY OF THE INVENTION In view of the above-mentioned circumstances, the present invention provides a heat exchanger having a core portion composed of plate fins arranged vertically in the left-right direction and flat tubes arranged in multiple stages in the horizontal state. The plate fin and the flat tube can be reliably joined and integrated by brazing in the furnace, and the strength of the plate fin can be secured and there is no hindrance to its louver processing. It is intended to provide.

[0007]

In order to achieve the above object, a heat exchanger according to a first aspect of the present invention comprises a plurality of plate fins which are vertically arranged at predetermined intervals in the left-right direction. A core portion is formed by flat tubes arranged horizontally in a notch portion recessed in the width direction from one side end of the plate fin and arranged vertically in multiple stages, and a heat exchange medium flowing through the flat tubes of the core portion. In a heat exchanger that performs heat exchange with external air, the flat tube is provided with a cover material made of a brazing sheet, which is substantially U-shaped in a side view and covers a main part of the upper and lower surfaces from one end thereof. It is characterized in that it is fitted into the notch of the plate fin and joined and integrated with the plate fin.

According to the first aspect of the present invention, the flat tube has its upper and lower main portions covered with a cover material from one end thereof, so that the flat tube does not easily deteriorate due to dew condensation and exhibits high durability. Since the cover material is made of brazing sheet, the plate fin and the flat tube are securely bonded and integrated by the brazing material of the cover material during brazing in the furnace, and the plate fin is made of a normal material such as an aluminum alloy. Therefore, there is no reduction in strength due to a decrease in wall thickness at the time of brazing, and louver processing can be performed on the plate fins without any trouble.

According to a second aspect of the present invention, in the heat exchanger of the first aspect, the flat tube and the cover material are both made of an aluminum alloy, and the cover material is lower in potential than the alloy material of the flat tube. The structure is made of an alloy material. In this case, the components of the cover material, which is more corrosive than the flat tube, are diffused to the surface of the flat tube made of a similar material during brazing in the furnace, and this functions as a sacrificial anticorrosion material. The durability will be further improved.

According to a third aspect of the present invention, in the heat exchanger according to the first or second aspect, a groove is provided on an outer peripheral surface of the cover member to fit a peripheral edge of the plate fin. In this configuration, when assembling the core portion, the notch portion of each plate fin is fitted into the groove of the cover material, so that the plate fins can be easily positioned and accurately arranged. Since they are attached and joined, the joining strength of the entire core portion is greatly improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the heat exchanger according to the present invention will be specifically described with reference to the drawings. FIGS. 1A and 1B show a first embodiment, FIGS. 2A and 2B show a second embodiment, and FIGS. 3A to 3C show a third embodiment. In these examples, the same reference numerals are given to the same parts as those of the heat exchangers shown in FIGS.

In FIGS. 1 (a) and 1 (b) showing the first embodiment, (1) is a band-shaped plate fin, and (3) is a plurality of channels (3) in the width direction formed by partition walls (3a). A flat tube made of an extruded material divided into 30), and (6A) is a covering material made of a brazing sheet bent in a substantially U shape in side view. These are all made of aluminum alloy, but the alloy material of the cover material (6A) is Zn, Sn, In.
The material is set to a material which is more potential than the alloy material of the flat tube by adding elements such as.

As shown in FIG. 4A, a large number of plate fins (1) are arranged at predetermined intervals in the left-right direction with the longitudinal direction being vertical in the core portion (10) of the heat exchanger. Notches (2) ... which are recessed in the width direction from one side end thereof are formed at regular intervals in the longitudinal direction, and uneven surfaces (1a) ... along the longitudinal direction are provided on the surface by louver processing. Have been. Thus, each notch (2) has a length greater than the width of the flat tube (3),
In addition, the vertical width is set to substantially match the thickness of the flat tube (3) with the cover material (6A) covered.

The cover member (6A) has a U-shaped bent width that is slightly shorter than the width of the flat tube (3).
The opening width of the inside of the character is set so as to substantially match the thickness of the flat tube (3).

The assembling of the core portion (10) of the heat exchanger (see FIG. 4A) is performed by cutting out notches (2) at each position in the longitudinal direction of the plate fins (1) arranged at predetermined intervals.
After fitting each flat tube (3) over
Cover material (6A) so as to enter the gap of this fitting part
Or a state where each flat tube (3) is covered with a cover material (6A) in advance.
By fitting (6A) between the notches (2)..., The assembled state shown in FIG. Then, as shown in FIG. 4A, the header (4A) (4
In the state where the entire heat exchanger including B) and the outlets (5A) and (5B) is assembled, brazing is performed in a furnace to join and integrate the whole.

When brazing in the furnace, the cover material (6
A) When the brazing material is dissolved, the plate fins (1) and the flat tubes (3) are covered with the cover material (6A).
..., but the components of the cover material (6A) are simultaneously diffused to the surface of the flat tube (3).

Accordingly, in the obtained heat exchanger, since the both sides in the width direction of each plate fin (1) project forward and backward from the flat tube (3), the water droplets of the condensed water are easily transmitted down. In addition to the above, a flat tube (3) covers a main part of the upper and lower surfaces from one side end thereof (6).
Since the component of the cover material (6A) covered with A) and diffused on the surface of the flat tube (3) functions as a sacrificial anticorrosive material, the flat tube (3) is less likely to be corroded and deteriorated by dew condensation water. Demonstrate extremely high durability. Also,
Since the plate fin (1) does not contain a brazing material, there is no decrease in wall thickness at the time of brazing, and sufficient fin strength can be secured, while louver processing can be performed without any trouble at the time of manufacturing itself.

In the second embodiment shown in FIGS.
The plate fin (1) and the flat tube (3) are the same as in the first embodiment, but the width of the cover member (6B) in the U-shaped bent state is the notch (2) of the plate fin (1).
Is set to approximately match the length. Then
The assembling of the core part (10) of the heat exchanger (see FIG. 4A) is performed by arranging plate fins (1) at predetermined intervals.
Notch (2) at each position in the longitudinal direction of
First, the cover member (6B) is fitted with its U-shaped bent side as the back side, and a flat tube (3) is inserted inside the fitted cover member (6B), or each cover member ( 6B) with the flat tube (3) fitted in advance, with the bent side of the cover member (6B) also fitted over the notches (2)...
The assembled state shown in FIG. Subsequent brazing in the furnace is the same as in the first embodiment.

The heat exchanger of the second embodiment is used in an installed state in which the flow of air is in the direction shown by the arrow a in FIG. In this case, since the cover material (6B) has a width that covers the entire cutout (2) of the plate fin (1), the water droplets of the dew condensation will travel down one side of the cover material (6B). However, the flat tube (3) is entirely covered with the cover material (6B), and the component of the cover material (6B) diffused on the surface of the flat tube (3) functions as a sacrificial anticorrosion material. Thus, as in the first embodiment, the flat tube (3) hardly causes corrosion deterioration and exhibits extremely high durability.

In the third embodiment, a cover material (6C) shown in FIG. 3A is used instead of the cover material (6A) in the first embodiment, and a cover material (6C) in the second embodiment is used.
A cover material (6D) shown in FIG. 3B is used instead of B). These cover members (6C) (6D) are similar in size and shape to the cover member (6A) or (6B), but have a large number of groove portions (60). (1) are provided at intervals corresponding to the arrangement intervals of.

Therefore, the core part (10) of the heat exchanger [FIG.
(Refer to (a))] when assembling each plate fin (1)
Notch (2) of cover material (6C) (6D)
0), the plate fins (1) ...
Can be easily positioned and accurately arranged.
In the heat exchanger obtained, the plate fins (1) and the cover material (6C) or (6D) are brazed and joined in the above-mentioned fitting state, so that the entire core part (60) is joined. The joining strength is greatly improved.

The heat exchanger of the first to third embodiments has a pair of headers (4B) (4B) as shown in FIG.
B) is the type arranged on both sides of the core part (10),
The present invention can be similarly applied to a heat exchanger using a serpentine tube, which has no headers (4B) and (4B) and is bent in a shape in which one flat tube is folded at a fixed length. That is, in the latter heat exchanger, the flat tubes (3) shown in FIGS. 1 to 3 correspond to the upper and lower multi-stage linear portions formed by folding back the serpentine tubes.

[0023]

According to the first aspect of the present invention, a flat tube is used as a heat exchanger having a core portion composed of plate fins arranged vertically in the left-right direction and flat tubes arranged horizontally in multiple stages in a horizontal state. It is excellent in corrosion resistance and durability, and can securely join and integrate the plate fin and the flat tube by brazing in a furnace, and can secure the strength of the plate fin and do not hinder the louver processing. Is done.

According to the second aspect of the present invention, there is provided the above-mentioned heat exchanger which is superior in corrosion resistance and durability of the flat tube.

According to the third aspect of the present invention, there is provided, as the above-mentioned heat exchanger, one which is easy to assemble a core portion and has excellent bonding strength of the entire core portion.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of a heat exchanger of the present invention,
(A) The figure is a perspective view of the components of the core before assembly,
(B) The figure is a longitudinal sectional side view of a main part of the core part after assembly.

FIGS. 2A and 2B show the second embodiment, wherein FIG. 2A is a perspective view of components of a core unit before assembly, and FIG. 2B is a vertical sectional side view of a main part of the core unit after assembly.

3 (a) and 3 (b) are perspective views of a cover member, and FIG. 3 (c) is a longitudinal sectional front view of a main part of a core part after assembly.

FIG. 4 shows a configuration example of a heat exchanger using a plate fin and a flat tube in a core portion, (a) is a perspective view of the entire heat exchanger, and (b) is a longitudinal sectional side view of a main portion in the core portion. It is.

FIG. 5 is a front view showing an example of a conventional heat exchanger using corrugated fins for a core portion.

FIG. 6 shows a state of water droplets adhering to a core portion using a corrugated fin. FIG. 6A is an enlarged front view of a main part when the flat tube is horizontal, and FIG. 6B is a case where the flat tube is vertical. It is an enlarged front view of the principal part.

[Explanation of symbols]

 1 Plate fin 2 Notch 3 Flat tube 6A-6D Cover material 10 Core part

Claims (3)

[Claims] 1. A plurality of plate fins arranged at predetermined intervals in the left-right direction in a vertical state, and horizontally inserted into cutouts recessed in the width direction from one side end of the plate fins to form a plurality of vertical tiers. A core portion is constituted by the arranged flat tubes, and in a heat exchanger that exchanges heat between a heat exchange medium flowing in the flat tubes of the core portion and external air, the flat tubes have one end thereof. Characterized in that it is fitted into a notch of the plate fin through a cover material made of a brazing sheet having a substantially U-shape in a side view and covers the main part of the upper and lower surfaces, and is joined to and integrated with the plate fin. vessel. 2. The heat exchanger according to claim 1, wherein the flat tube and the cover material are both made of an aluminum-based alloy, and the cover material is an alloy material having a potential lower than that of the flat tube. 3. The heat exchanger according to claim 1, further comprising a groove formed on an outer peripheral surface of the cover member to fit a peripheral edge of the plate fin.