JPH09280774A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the heat exchanging performance of a heat exchanger in a prescribed dimension and require no sealing gasket below a header plate. SOLUTION: The edge part 38 of a header plate is provided with a U shaped groove between an inner wall part 52, an outer wall part 54 and a base part 56. The side wall 44 of a header cover 40 is fitted into and soldered to the groove. This groove forms a skirt part for preventing air from entering a space E between a corrugated insert 26 and the header plate 30.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat exchanger with a brazed fluid header, mainly for motor vehicles.

More particularly, the present invention includes an oval cross-section body portion having a number of tubes, each tube joined via a transition portion provided at an end portion having a different cross-section. A header plate having a number of inserts and a base portion disposed between the tubes, the end portion of the tube extending through the base portion,
The header plate relates to a heat exchanger having a peripheral edge portion for attaching the wall of the header cover to the edge portion by brazing.

[0003]

2. Description of the Prior Art A heat exchanger of the above type is described, for example, in French Patent Publication No. 2,711,236. This type of heat exchanger is a radiator for engine cooling,
Alternatively, it constitutes either a radiator for a vehicle air conditioner and is suitable for use in a vehicle having a heat engine. The tubes of such heat exchangers generally have a flattened directional cross section, the cross section being joined to the end of a tube having a smaller flattened cross section. The cross-section of this end is generally oval or round, with the end and body joined together through the transition section of the tube. Such a transition part comprises two walls, which usually form a V-shape. This transition is
It extends over a small but non-negligible height or axial length.

The inserts which make up the cooling fins in such heat exchangers are usually manufactured in the form of corrugated fins, which are arranged between the body parts of the tubes.
The tube body extends to a height where it is joined to the corresponding transition.

Furthermore, in known heat exchangers of the above type,
The peripheral edge portion of the header plate is manufactured in the form of a simple upset edge, which upset edge is joined at a right angle to the base portion of the header plate. This enables the header cover and the header plate to be brazed together so that the wall of the header cover can be fitted over the peripheral edge portion of the header plate so as to form the fluid header of the heat exchanger together. . As a result, a free space is formed between the base portion of the header plate and the corrugated insert, i.e. between the base portion of the header plate and the final fin of the bundle of tubes.

[0006]

A portion of the air flow through the bundle of tubes does not exchange heat with the fluid (typically water) flowing within the bundle of tubes, without leaving this gap or free space. The presence of such free space is disadvantageous to the good operation of the heat exchanger if it has the property of passing through.

[0007] To overcome these drawbacks, the free space constructed between the insert of the bundle of tubes and the base portion of the header plate to prevent the passage of air through the free space as described above. It is known to provide gaskets or fillers, usually of the foam type. Such a solution is not entirely satisfactory. The first reason is that the gasket has a property of deteriorating and decomposing due to aging, and the second reason is that the free space occupied by the gasket does not perform a specific effective function, and the heat exchanger does not function. This is because the overall size is increased.

The main object of the present invention is to eliminate the above-mentioned drawbacks.

[0009]

SUMMARY OF THE INVENTION According to the present invention, an oval cross-section body having multiple tubes, each tube joined via a transition section interposed at an end having a different cross section. A header plate having a plurality of inserts and a base portion disposed between the tubes, the end portion of the tube extending through the base portion, the header plate being brazed to the header cover. A heat exchanger having a peripheral edge portion for attaching a wall of the inner peripheral wall portion to the edge portion, the peripheral edge portion of the header plate defining a U-shaped groove partly bounded by an inner wall portion, The wall portion extends at a right angle to the base portion of the header plate on the same side as the insert, and the depth of the inner wall portion matches the depth of the transition portion of the tube, The groove is bounded by an outer wall portion that constitutes a flange and a base portion that joins the inner wall portion and the outer wall portion, so that the inner wall portion and the outer wall portion have a header cover therebetween. The gap is formed to have a thickness substantially equal to that of the wall, so that the header cover can be fitted in the U-shaped groove and brazed to the header plate.

Therefore, the peripheral edge portion of the header plate constitutes a groove into which the wall of the header cover is fitted. That is, the free edge of the wall of the header cover is inserted in the groove. This groove extends from the header plate on the same side as the insert of the bundle of tubes, so that its peripheral edge part constitutes a kind of skirt surrounding the free space, which free space is It is configured between the base portion and the insert.

Since the depth of the inner wall portion of the U-shaped groove matches the depth of the transition portion of the tube, the skirt portion has a depth approximately equal to the depth of the free space between the base of the header plate and the corrugated insert. It extends over a corresponding depth or height.

Therefore, according to a preferred feature of the present invention,
The base portion of the U-shaped groove defined by the peripheral edge portion is in contact with at least a portion of the insert. In other words, the skirt engages the insert, thus providing a peripheral seal. As a result, it is not necessary to provide a sealing gasket in the free space, such as the foam gasket used in the prior art.

Therefore, as the air stream passes through the bundle of tubes of the heat exchanger during operation, there is no risk of some of the air passing through the free space formed between the header plate and the insert. This improves the heat exchange performance of the heat exchanger.

According to another preferred feature of the invention, the outer wall portion of the U-shaped groove has a depth at least equal to the depth of the inner wall portion. As a result, the U of the header plate
The fitting of the side wall of the header cover in the groove is improved.

Before fixing the header cover and the header plate by brazing, the U formed by the peripheral wall portion is provided with a seam lug for facilitating the locking of the header cover in place with respect to the header plate.
Preferably, the outer wall portion of the gutter extends in places.

In a preferred embodiment of the invention, the outer surface of the wall of the header cover has an outer coating of brazing metal, which coating defines the U formed by the wall of the header cover and the peripheral edge portion. It is possible to form a braze joint between the groove and the outer wall part.

In another variant of the heat exchanger according to the invention, the inner surface of the wall of the header cover has a coating of brazing metal, which coating constitutes the wall of the header cover and the peripheral edge portion. It is possible to form a brazing joint between the outer wall portion of the U-shaped groove formed.

In yet another variation, the header plate has a brazing metal coating on the inner surface of the wall portion of the U-shaped groove defined by the peripheral edge portion, which coating causes the wall of the header cover to be removed. It is possible to form brazing joints on both sides of the.

According to another preferred feature of the invention, the body portion of each tube has a flat cross section and its ends are
It has a smaller flat cross section that is substantially elliptical, and thus the transition section has two opposing bevels forming a V-shape.

The heat exchanger preferably has two rows of tubes arranged in pairs.

Preferably, the end of the tube is secured by brazing to a collar portion surrounding a corresponding hole formed through the header plate.

Therefore, according to the present invention, it is possible to manufacture a heat exchanger in which all parts are fixed by brazing.

Other features and advantages of the present invention will become more apparent on reading the following detailed description of some preferred embodiments of the invention, given by way of non-limiting example only, with reference to the accompanying drawings, in which: Let's do it.

[0024]

DETAILED DESCRIPTION OF THE INVENTION Reference is first made to FIGS.
These figures show a portion of a heat exchanger including a number of heat exchange tubes 10, each tube having a body section 12 of flat directional cross section joined to an end 14 of the tube. The cross section of the end portion 14 is different from the directional cross section of the main body portion 12, and in this example, it is substantially elliptical as seen from FIG. In each tube, the body portion 12 is joined to the ends via a transition portion 16. In this example, the transition part 16
Has two opposite inclined surfaces 18, which, as can be seen in FIG. 1, form an outwardly flared V-shape. Each inclined surface 18 is a main surface 2 of the body of the tube.
0 is bonded to the corresponding surface 22 of the end portion of the tube. These tubes 10 may be, for example, French Patent Publication No. 2,715,216 or French Patent Publication No. 2,715,217.
Can be manufactured by the method described in the publication

The tubes 10 are arranged to form a tube bundle 24, which is shown in FIG.
As can be seen from the two rows of tubes 10 R1 and R
Consists of two. These tubes are arranged in pairs and a common generatrix G (FIGS. 2 and 3) is provided so that the two main axes A of either pair of tubes are aligned with each other as shown in FIG. Are in contact with each other along.

A corrugated insert 26, which constitutes a cooling fin, is arranged between the tubes 10. The inserts 26 extend along the entire length of the tube body portion 12, with each insert 26 having an end 28 located at the height of the junction between the tube body portion 12 and the transition portion 16.
have. In other words, no corrugated insert is provided at the axial height or axial length of the tube corresponding to the transition section 16.

The heat exchanger has a header plate 30. The header plate has a generally rectangular base portion 32 provided with a number of through holes 34. The hole 34 is
A collar portion 16 bounds one end 14 of the tube 10 for fitting therein. The end 14 fits within the collar portion 36 and is secured to the collar portion by brazing.

The header plate 30 also has a peripheral edge portion 38. Next, the peripheral edge portion will be further described. A fluid header cover 40 is fitted to and brazed to the peripheral edge portion 38 so that the header cover 40 and the header plate 30 together form the hollow fluid header of the heat exchanger. The header cover 40 includes a generally rectangular base wall 42 that is joined to a continuous side wall 44 that surrounds the generally rectangular open surface of the header cover that is closed by the header plate 30.

The interior of the header is divided by a longitudinal bulkhead 46 into two compartments 48 and 50. The longitudinal bulkhead 46 is located between the header plate 30 and the base wall 42 of the header cover 40 and is brazed to the header plate 30 and the base wall 42, and the compartment 48 is in the row R1. It communicates with the tubes, while the compartment 50 is arranged to communicate with the tubes in row R2.

The peripheral edge portion 3 of the header plate 30
8 constitutes a U-shaped groove whose part is bounded by the inner wall portion 52. The wall portion 52 is on the opposite side of the header cover 40, that is, on the same side as the insert 46,
It extends at a right angle to the base portion 36 of the header plate. The inner wall portion 52 has a depth H1 that matches the depth H2 of the transition section 16 of the tube. In this example, the depths H1 and H2 are substantially equal to each other. The inner wall portion 52 is joined to the outer wall portion 54 and the outer wall portion 54
Is parallel to the inner wall portion 52 so as to form a flange in the embodiment shown in FIGS. The outer wall portion 54 has a depth H2 slightly deeper than the depth H1 of the inner wall portion. The inner wall portion 52 and the outer wall portion 54 are
They are joined together via a base portion 56 which is substantially semi-circular in cross section. These two walls 52 and 54 form a gap I between them. This gap I facilitates fixing by brazing to the peripheral edge portion 38 of the header cover 40 so that the side wall 44 of the header cover 40 is facilitated.
Is almost equal to the thickness of.

The outer wall portion 54 of the edge portion 38 is shown in FIG.
And as can be seen in FIG. 2, seam lugs 58 extend in places. The seam lugs 58 apply pressure to the sidewalls 44 of the header cover 40 and cause the header cover 4 to
0 and the header plate 30 are assembled by brazing until the header cover 4 is attached to the header plate 30.
0 is held at a predetermined position. Furthermore, the header plate 30 includes folding lugs 60 (see FIG. 1) which can act as fixed lugs, for example.

Accordingly, the peripheral edge portion 38 of the header plate 30 defines a U-shaped groove which fits the sidewall 44 of the header cover 40 into the header plate 30 for subsequent brazing operations. Up to this point, it can be locked in place.

In this example, all parts of the heat exchanger, namely tube 10, insert 26, header plate 30, header cover 40, and longitudinal valve head 46 are metal parts, preferably made of aluminum. They are fixed together by brazing. For such fixing purposes, at appropriate positions on appropriate parts,
It is necessary to provide a coating of brazing metal.

Next, please refer to FIG. 4 to FIG. These figures show three examples of brazing joints for fixing the header cover 40 to the header plate 30.

In the example shown in FIG. 4, the sidewall 44 of the header cover is brazed so that a braze joint B is formed between the sidewall 44 and the outer wall portion 54 of the U-shaped groove in the peripheral edge portion 38. It has a metallic outer coating 62.

In FIG. 5, the fluid header side wall is such that a braze joint B between the header cover side wall 44 and the outer wall portion 54 is formed between the latter and the U-shaped groove inner side wall portion 52. 44 has an inner braze metal coating 64.

FIG. 6 shows a modified structure in which the header plate 30 has a coated inner braze metal surface 66 on the surfaces of the wall portions 52, 54 and 56 in the U-shaped groove. With such a structure, it is possible to form the double brazed joint B. That is, the sidewalls 44 of the header cover are brazed to both sides of the peripheral edge portion 38.

In FIG. 1, the end 28 of the corrugated insert 26 is shown.
At the abutment is a base portion 56 of a U-shaped groove, which forms a kind of skirt having a substantially rectangular cross section. This skirt encloses a free space E defined between the end 28 of the insert 26 and the base portion 32 of the header plate 30. This space E is the space occupied by the foam type filling gasket as described above in the conventionally known heat exchanger.

Therefore, when the airflow is passed over the bundle of tubes 24, there is no risk that a part of this airflow will be diverted and will pass through this space E and will no longer function as a heat exchanger. As a result, the thermal efficiency of the heat exchanger as a whole is improved, which makes it possible to reduce the overall size for a given performance.

The outer ends of the tubes 10 within the tube bundle 42 may be joined to another fluid header or together by a U-shaped vent tube.

After assembling the various parts of the heat exchanger together, the heat exchanger is placed in a suitable oven so that the brazing metal can be melted and a brazing operation is performed to secure the various parts together.

The heat exchanger of the present invention is adapted to be used either as a radiator for cooling the heat engine of a vehicle or as a radiator for heating a vehicle.

Of course, the invention is not limited to the embodiments described above, but also includes other variants. For example, the heat exchanger tubes may have only one row, or three or more rows. In the case of heat exchangers with three rows of tubes, the tubes may or may not be in contact with each other, as desired.

[Brief description of drawings]

FIG. 1 is a partial side view showing a part of a heat exchanger of the present invention by cutting away.

FIG. 2 is a sectional view taken along line II-II in FIG.

3 is an end view of two adjacent tubes forming part of the heat exchanger in FIGS. 1 and 2. FIG.

FIG. 4 is a partial cross-sectional view of the brazing assembly of the U-shaped groove of the header plate and the wall of the header cover in one embodiment of the present invention.

FIG. 5 is a view similar to FIG. 4 showing another embodiment of the present invention.

FIG. 6 is another view similar to FIG. 4, showing yet another embodiment of the present invention.

[Explanation of symbols]

 10 heat exchange tube 12 body part 14 end part 16 transition part 18 facing inclined surface 20 major surface 22 corresponding surface 26 insert 28 end part 30 header plate 32 base part 34 hole 36 collar part 38 peripheral edge part 40 fluid header cover 42 Base wall 44 Side wall 46 Bulkhead 48, 50 Compartments 52 Inner side wall portion 54 Outer side wall portion 56 Base portion 58 Lug 62 Outer coating 66 Inner coating

Claims (10)

[Claims] 1. An oval cross-section body part (1) having a large number of tubes (10), each tube being joined via a transition part (16) provided at an end (14) having a different cross section. 12) and includes a header plate (30) having a number of inserts (26) and a base portion (32) disposed between the tubes (10), the ends of the tubes being through the base portion (32). The header plate (4) by brazing.
In a heat exchanger having a peripheral edge portion (36) for attaching a wall (44) of 0) to said edge portion (38), a peripheral edge portion (38) of a header plate (30)
Defines a U-shaped groove bounded in part by an inner wall portion (52), the inner wall portion (52) on the same side as the insert (26), the base portion (32) of the header plate (30). ), And the depth (H1) of the inner wall portion is equal to the depth (H1) of the transition portion (16) of the tube.
2), said groove being bounded by an outer wall portion (56) forming a flange and a base portion (56) joining said inner and outer wall portions,
Therefore, the inner wall portion and the outer wall portion form a gap (I) between them which is substantially the same as the thickness of the wall (44) of the header cover (40), whereby the header is formed in the U-shaped groove. A heat exchanger characterized in that a cover (40) is fitted and can be brazed to a header plate. 2. A base portion (56) of a U-shaped groove constituted by a peripheral edge portion (38) is provided with an insert (2).
The heat exchanger according to claim 1, wherein the heat exchanger is in contact with at least a part of (6). 3. The outer wall portion (54) of the U-shaped groove has a depth (H3) equal to the depth (H1) of the inner wall portion (52). Or the heat exchanger according to 2. 4. The header plate (3) until the header cover and the header plate are fixed by brazing.
The outer wall portion (54) of the U-shaped groove formed by the peripheral wall portion (38) by the seam lugs (58) for facilitating the locking of the header cover (40) with respect to 0) in place is here and there. The heat exchanger according to any one of claims 1 to 3, which is extended. 5. The wall (4) of the header cover (40).
The outer surface of 4) has a brazing metal coating (62) by means of which said wall of the header cover (44).
A brazing joint (B) can be formed between the outer wall portion (54) of the U-shaped groove formed by the peripheral edge portion (38). Item 5. The heat exchanger according to any one of items 1 to 4. 6. The inner surface of the wall (44) of the header cover has a coating of braze metal (64) that causes the wall (44) of the header cover and the peripheral edge portion (38). 5. A brazed joint (B) can be formed between the outer wall portion (54) of the U-shaped groove constituted by and the brazing joint (B) can be formed. The heat exchanger described. 7. The header plate (30) has a brazing metal coating on the inner surface of the wall portion of the U-shaped groove defined by the peripheral edge portion (38), the coating of the header cover causing Heat exchanger according to any one of the preceding claims, characterized in that it is possible to form brazing joints (B) on both sides of the wall (44). 8. The body portion (12) of each tube has a flat cross section and its end portion (14) has a smaller flat cross section of substantially elliptical shape, whereby the transition portion (16) comprises:
Heat exchanger according to any one of the preceding claims, characterized in that it has two opposite inclined surfaces (18) forming a V-shape. 9. A pair of tubes (10) arranged in pairs (R1) (R2).
The heat exchanger according to any one of to 8. 10. A collar portion (36) surrounding a corresponding hole (34) provided through the header plate (30).
To the end portion (1) of the tube (10) by brazing.
4) is fixed, The heat exchanger in any one of Claims 1-9 characterized by the above-mentioned.