JPH03164694A - Heat exchanger - Google Patents

Abstract

PURPOSE:To perform a rational reinforcement of a header and improve a compressive strength by a method wherein an annular or arcular restricting reinforcing piece is fitted to an outer periphery of an intermediate part in a longitudinal direction of a header, brazed and integrally connected. CONSTITUTION:A restricting recinforcing piece 11 is fitted to an outer periphery of an intermediate part in a longitudinal direction in order to prevent a deformation of an expanding pipe as an inner pressure is increased at headers 3 and 4 composed of a formed and connected pipe. The reinforcing piece 11 is brazed and integrally connected. The restricting and reinforcing piece 11 is composed of an aluminum annular piece having a substantial same inner diameter as an outer diameter of each of the headers 3 and 4. The reinforcing piece 11 is fitted to the headers 3 and 4 before fixing to a tube 1 at an assembly stage of a heat exchanger. They are brazed and connected with a brazing material layer at outer peripheral surfaces of the headers 3 and 4 in concurrent with a mutual brazing of the tube 1, fins 2 and headers 3 and 4. With such an arrangement, as an inner pressure is increased, an excessive tension force is prevented from being applied to the connection part of the header and further a pressure damage is prevented from being generated from the connection part to the header.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to heat exchangers such as those used as condensers in automobiles and domestic air conditioners, and particularly to so-called header-type aluminum heat exchangers.

BACKGROUND ART Recently, as this type of heat exchanger, for example, the Utility Model Application No. 63-3
As shown in Japanese Patent No. 4466, a large number of flat tubes are arranged in parallel at a predetermined pitch between a pair of headers arranged in parallel, and both ends of the tubes are connected to the header to communicate with the adjacent tubes. Integrated heat exchangers with corrugated fins interposed between them are increasingly being used.

Furthermore, in order to achieve mass production, weight reduction, and cost reduction, the header of such a heat exchanger is formed by bending a relatively thin plate material made of plating sheets, etc. However, a jointed pipe formed into a tubular shape by joining the side edges by brazing or electric resistance welding is generally used.

Problem to be Solved by the Invention However, in a heat exchanger using a header made of molded joint pipes with bending specifications as described above, the joints along the axial direction that exist in a part of the cross section of the header Since the joint is the weak point in terms of strength, there is a risk that the header will break from that joint if high internal pressure is applied. There was a risk that there would be concerns about strength.

This invention was made to address these problems and to improve the pressure resistance of a heat exchanger using a header made of molded jointed pipes by rationally reinforcing the header. be.

Means for Solving the Problems The inventors repeatedly conducted various pressure resistance tests for the above-mentioned purpose, and found that when a header breaks, it first tends to bulge in the radial direction as the internal pressure increases; Eventually, it was discovered that if the rupture exceeded the rupture limit, the pipe would rupture at the joint, which is a weak point in terms of strength.From these results, the most effective means of preventing rupture was to suppress the bulge in the header. We found that.

Therefore, the main purpose of the present invention is to attach a restraining reinforcing piece to the outer periphery of the header to prevent the header from bulging. A heat exchanger that is connected to a pair of headers and has fins interposed between adjacent tubes, the header having a molded joint pipe having a joint part along the axial direction in a part of the cross section. In the aluminum heat exchanger configured, an annular or arc-shaped restraining reinforcing piece is fitted to the outer periphery of the intermediate portion in the longitudinal direction of the header and is integrally joined by brazing. The main points are as follows.

Furthermore, since the above-mentioned restraint reinforcing piece is integrally attached to the header, it can be used to attach the mounting bracket, which is an accessory part of the heat exchanger, if necessary. The above-mentioned bracket is previously provided integrally with the restraint reinforcing piece.

The action restraining reinforcing piece is fitted into the header during the assembly of the heat exchanger, and is brazed at the same time as the core is brazed, so that it is closely bonded and fixed to the outer circumferential surface of the header. This acts to prevent expansion of the header, that is, bulge in the pipe diameter direction. Therefore, as the internal pressure increases, excessive tensile force is prevented from acting on the joint of the header, and pressure breakdown from the joint is prevented from occurring in the header.

In addition, during brazing, the restraining and reinforcing pieces restrain the header from the outside, thereby preventing the joints of the header from exhibiting a tendency to open during brazing, thereby preventing joint failure.

Embodiment In FIGS. 1 to 5, (1) indicates a plurality of flat aluminum tubes arranged vertically in parallel at a predetermined pitch in a horizontal state, and (2) indicates the adjacent tubes (1) ( 1) Aluminum fins interposed between them.

The tube (1) is made of a flat extruded aluminum material, and a porous type so-called harmonica tube is generally used, but an electric resistance welded tube may also be used.

The fin (2) is a full-gate fin made of an aluminum plating sheet with a brazing metal layer coated on one or both sides of the core material, and has approximately the same width as the tube (1), and is attached to the tube by brazing. It is joined. Note that the fins (2) are not limited to full-gate fins, and plate-type fins may be used, but in any case, it is preferable to use fins with cut and raised louvers.

(3) and (4) are a pair of left and right headers.

Tube insertion holes (5) are bored in each header at predetermined intervals along the length direction, and the ends of each tube (1) are inserted into the chain holes (5) and firmly secured by brazing. is connected to.

Furthermore, an inlet pipe (6) and an outlet pipe (7) are connected to the upper and lower ends of the left header (3), respectively, and lid pieces (8) (8) are connected to both the upper and lower ends of the right header (3). is installed. In addition, (9) (9) shown in FIG. 2 is a side plate arranged on the outside of the outermost corrugated fin (2).

The left header (3) is provided with two partition plates (10) at predetermined intervals to divide the interior of the header into three upper and lower chambers. In addition, one partition plate (1
0) is provided.

The heat exchange medium that has flowed into the left header (3) from the heat exchange medium inlet pipe (6) flows in a meandering manner around the entire heat exchange medium passage constituted by the tube group, and between the tubes (1) and (1). It exchanges heat with the air flowing through the air flow gap including the corrugated fins (2) formed therebetween, and is condensed and discharged from the heat exchange medium outlet pipe (7).

By the way, as shown in FIG. 4, the headers (3) and (4) are made by a double-sided plating sheet in which both sides of a core material (3a) are coated with a brazing material layer (3b), with both side edges abutted. The pipe is formed by bending it into a cylindrical shape and brazing the side edges together at a joint (3c). Note that this header may be an electric resistance welded tube whose side edges are joined by welding instead of brazing.

Therefore, the header (3) consisting of the above-mentioned molded joint pipe (
4), in order to prevent deformation of the bulging tube shape due to an increase in internal pressure, a restraining reinforcing piece (11) is fitted to the outer periphery of the intermediate portion in the longitudinal direction, and is integrally joined by brazing. This restraint reinforcing piece (11) has an inner diameter of the header (3) (4).
) is an annular piece or a short cylindrical piece made of aluminum with an outer diameter of When the tubes (1), fins (2), and headers (3) and (4) are brazed to each other, they are simultaneously brazed and joined to the headers (3) and (4) using the brazing metal layer (3b) on the outer peripheral surface thereof. It is something that The reinforcing piece (11) may also be formed from a cladding material or plating sheet having a brazing filler metal layer on the inner surface.

Further, the attachment position of the restraint reinforcing piece (11) to the header (3) (4) is not particularly limited, but it is preferable to attach it to the part of the header (3) (4) that is most likely to bulge. .

Therefore, as shown in Fig. 2, the partition plate (lO) (10)
It is desirable that the tube be provided at the center between the partition plate (10) and the tube end.

FIG. 6 shows a modification of the restraint reinforcing piece (21). The reinforcing piece (21) has a notch (21a) in a part of the circumference.
) is formed into a C-shaped notched ring shape or an arc shape that exceeds a semicircle.

Therefore, the reinforcing piece (21) has its notch (21a)
inwards, i.e. at the joints of headers (3) and (4) (
The headers (3c) are oriented so that the notch (21a) is not located therein, and are tightly fitted onto the outer circumferential surfaces of the headers (3) and (4), and are bonded thereto. When using this notched annular or arc-shaped reinforcing piece (21), when assembling the heat exchanger, the tube (1) is attached to the header (3) (4).
), then attach the reinforcing piece (21) to the header (3).
(4) can be attached.

Another embodiment shown in FIGS. 7 and 8 is one in which a restraining reinforcing piece (31) is previously provided with a mounting bracket (32) for mounting the heat exchanger on a vehicle, etc. when the heat exchanger is used. It is.

That is, a restraint reinforcing piece (
31), a flat plate-shaped bracket (32) is integrally provided on the outer peripheral surface of the opposite side of the notch (31a). Therefore, the restraining reinforcing piece (31) is fitted to the outer circumferential surface of the header (3) (4) at a position near the end thereof, and is integrally attached by brazing, so that the mounting bracket (32) is attached at the same time. are attached in an outwardly protruding manner at the end positions of the headers (3) and (4). The restraint reinforcing piece (31) with the bracket (32) may be manufactured from an aluminum extrusion molded material, or may be manufactured by pressing an aluminum plate material.

By adopting the mounting means of the bracket (32) as in this embodiment, it is no longer necessary to attach a separate steel or aluminum mounting bracket by screwing or welding after assembling the heat exchanger core as in the past. When brazing the heat exchanger core, restraint reinforcing pieces (3
1) can be installed by simultaneously brazing the headers (3) and (4), which reduces assembly production costs and eliminates the need to use screws that can cause electrical corrosion. Therefore, it is also useful as a corrosion prevention measure.

9 and 10 show a modification of the restraining supply piece (31) with a bracket (32), in which a positioning protrusion is attached to one side edge opposite to the notch (31a) of the reinforcing piece (31). (33) are integrally formed. The positioning protrusion (33) is integrally provided to protrude from the negative side edge toward the center of the heat exchanger core, and its tip is bent inward so as to fit between the adjacent tubes (1) (1). It is said that it fits into the Therefore, the restraint reinforcing piece (31) is attached to the header (3).
<4) and positioning the positioning protrusion (33) between the adjacent tubes (1) (1), the mounting position of the bracket (32) can be determined at the time of temporary assembly before brazing. It is easy to set correctly.

Effects of the Invention As described above, the present invention provides a heat exchanger using a molded joint pipe having a joint part in a part of the circumferential direction, that is, a part of the cross section, as a header. An annular or arc-shaped restraining reinforcing piece is fitted to the outer periphery of the intermediate portion and is bonded to the outer periphery of the heat exchanger, thereby preventing the header from expanding and deforming in the circumferential direction due to an increase in the internal pressure of the heat exchanger. It can be restrained with reinforcing pieces to prevent its deformation. Therefore, it is possible to prevent the joint from being overloaded due to an increase in internal pressure, thereby effectively preventing the breakage of the heat exchanger, thereby improving the pressure resistance of the heat exchanger.

Furthermore, since the restraining reinforcing piece is integrally brazed to the header, it can be attached by bracket brazing at the same time as the components of the heat exchanger core are brazed, which is advantageous in terms of manufacturing. Of course, the restraint reinforcing pieces also effectively prevent the joints of the header from opening during brazing, so when using a header made of molded joint pipes according to brazing specifications, the joints of the header itself It is possible to prevent bonding defects from occurring and improve productivity.

Furthermore, as claimed in claim (2), by integrally providing the binding reinforcing piece with the mounting bracket,
By attaching the reinforcing piece to the header, a heat exchanger with mounting brackets can be manufactured all at once, which greatly improves productivity compared to the case where the brackets are attached separately. This eliminates the risk of electrolytic corrosion, which is the case when brackets such as these are attached using separate screws.

[Brief explanation of the drawing]

The drawings show a heat exchanger for a condenser as an embodiment of the present invention. FIG. 1 is a perspective view showing the ladder tube and fins in a separated state, FIG. 2 is an overall front view, and FIG.
The figure is a left side view, FIG. 4 is an enlarged sectional view taken along the line IV--IV in FIG. 2, FIG.
The figure is an enlarged sectional view equivalent to FIG. 5 showing a modified example of the restraint reinforcing piece, FIG. 7 is a front view of the main part of another embodiment in which the restraint reinforcing piece is configured with a mounting bracket, and FIG. 8 is a Figure 7 IX
FIG. 9 is a sectional view taken along the line -IX; FIG. 7 shows a modified example of the restraint reinforcing piece with the mounting bracket; FIG. (1)...tube, (2) (4)...header (3C) (21) (31)...restraint reinforcing piece, racket. ...Fin, (3) ...Joint part, (11) (32) ...Mounting bracket and above Fig. 4 Fig. 5 Fig. 6

Claims (2)

[Claims] (1) A heat exchanger in which a large number of flat tubes arranged in parallel are connected at both ends to a pair of headers, and fins are interposed between adjacent tubes,
In an aluminum heat exchanger in which the header is configured with a formed joint pipe having a joint part along the axial direction in a part of the cross section, an annular or arc-shaped restraint is provided on the outer periphery of the intermediate part in the longitudinal direction of the header. A heat exchanger characterized in that reinforcing pieces are fitted together and integrally joined by brazing. (2) The heat exchanger according to claim (1), wherein the restraining reinforcing piece integrally has a bracket for mounting on a vehicle or the like.