WO2010049261A1 - Fin for a heat exchanger, and heat exchanger including such a fin - Google Patents

Abstract

The invention relates to a fin (6) for a heat exchanger that comprises a body provided with at least one hole (8) for the passage of a tube (4) of said heat exchanger (1) and a so-called spacing means (14), the hole (8) having an outline with two so-called large sides (10) and two so-called small sides (12), and in which the spacing means (14) is provided on a small side (12) of the outline of the hole (8) for the passage of the tube (4). According to the invention, the spacing means (14) includes a bearing surface (16) capable of bearing another fin (6). The invention can particularly be used in the automotive industry.

Description

 Aitettβ for heat exchanger and heat exchanger comprising a fin tiler

The invention relates to a fin for a heat exchanger and a heat exchanger comprising a fin fin.

It relates more particularly to a fin for a heat exchanger comprising a body provided with at least one hole for the passage of a tube of the heat exchanger and a means called spacing, fin in which the hole has an outline with two so-called large sides and two so-called small sides, and, wherein the spacing means is located on a small side of the contour of the passage hole of the tube.

A teile fin is used in a mechanical type said exchanger with reference to its method of assembly, for example an engine cooling radiator,

A mechanical type heat exchanger is generally composed of at least one heat exchange bundle comprising tubes and heat exchange elements, called fins. The fins are placed parallel to each other and perpendicular to the tubes. In other words, the fins are superimposed on each other, In general, the fins are pierced with holes for the passage of the tubes, the number of holes being equal to the number of tubes of said row.

Maintaining the tubes-aillettes beam is made mechanically by means of a tool, also called olive, introduced inside the tubes so as to deform the walls of the tubes and forcibly apply against the holes made in the fins. The fins are spaced two by two in a separation step, of the order of a millimeter, for example.

The ends of the tubes are then each inserted in a collector plate provided with openings for receiving the tubes. The collector plates are subsequently capped by lids so as to form collector boxes.

It is furthermore known, in a mechanical type exchanger, to equip the plate collector of a seal. The assembly of the tubes and the collector plates is carried out by a crimping operation, called "flaring", of flaring the respective ends of the tubes to compress the seal and thus ensure a definitive and tight connection between the ends of the tubes. and the plate.

A fin as described above is known in particular from US 3,771,595. In this document, there is no separation between two adjacent fins by means of spacing means. This spacing means is obtained by cutting and perforating the metal strip constituting the fin in an identical cut the shape of the section of the tubes, while sparing pieces of material around the perimeter of the cut. These pieces of material, also called collars, are then raised to form the spacing means,

The heat exchanger of US 3,771,595 has oval section tubes. The passage holes for the tubes of the fin are therefore also oval with two perpendicular axes of symmetry respectively having a large and a small dimension.

However, these fins have the disadvantage that they can not be applied to heat exchangers in which the separation pitch between two fins is greater than the smallest dimension of the through hole for the heat exchanger tube.

Indeed, in such a case, the separation step of the aiietîe can not be greater than the small size of the passage hole of the tube. In other words, in this document, the separation step is limited by the height of the collar.

To remedy this drawback, the invention proposes a fin as described above, wherein the spacing means comprises a bearing surface adapted to support another fin

Such a fin makes it possible to obtain a separation pitch greater than the smallest dimension of the tube passage and this taking into account a possible recalibration of the separation step. Indeed, in the context of the invention, the bearing surface is located in the extension of the spacer means, which adjusts the separation step regardless of the height of the spacer or collar.

Particular embodiments of the invention propose that:

the bearing surface capable of supporting another fin is made from the material of said spacer means,

- The bearing surface adapted to support another fin is made in the form of a raised edge substantially parallel to a so-called plane of general extension of the fin,

the fin additionally comprises at least one means capable of disturbing a flow of air passing through the fin, and

- The means capable of disturbing the air flow is achieved by louvers, said louvers being parallel to the direction of said air flow.

The invention also relates to a heat exchanger comprising at least one fin as described above and in which the fin is traversed by heat exchange tubes.

In the detailed description which follows, made only by way of example, reference is made to the accompanying drawings, in which:

FIG. 1 represents a schematic view of a mechanical type heat exchanger,

FIG. 2 is a partial perspective view from above of a bundle of tubes and fins according to the invention

FIG. 3 is a partial perspective view of a fin according to the invention,

FIG. 4 represents a partial view in perspective and on the side of a bundle of tubes and fins according to the invention, and FIG. 5 represents the different steps of a part of the method of manufacturing a fin according to the invention,

As illustrated in FIG. 1, a heat exchanger 1 of the mechanical type comprises two manifolds 2, The manifolds 2 are put in communication via at least one series of aligned tubes 4 in which circulate a heat transfer fluid.

The heat exchanger 1 may in particular be used as a cooling radiator of the engine coolant. In such a case, the coolant is engine coolant such as, for example, water with added glycol.

In the embodiment illustrated in FIGS. 2 to 4, the tubes 4 are of obedient shape with two so-called large sides and two so-called small sides, the small sides being of rounded shape. In this embodiment, the large opposite sides each have a concavity. This form of tube is also called "bean" or "peanut" form.

The tubes 4 are aligned in parallel in a direction said first direction. The first direction is, here, perpendicular to the direction of a flow of air F through the heat exchanger. In other words, the tubes are superimposed on each other in a first direction.

The coolant circulating in the tubes 4 exchanges calories with the air flow F. To increase the heat exchange between the coolant and the air flow, there is provided, between the manifolds 2 exchange elements parallel fins, here made in the form of fins 6. A fin 6 is intended to be traversed by the air flow in a given direction said second direction.

The fins 6 are arranged transversely to the axis of the tubes 4 and parallel to the manifolds 2. In other words, the fins 6 are superimposed on each other, the distance separating two adjacent fins being designated by separation step. The direction of superposition of the fins 6 is perpendicular to the direction of superposition of tubes 4.

In this example, the fins 6 are metal strips of substantially rectangular shape and have dimensions in width and in length substantially equal to those of the manifolds 2, Each fin 6 extends substantially in a plane called yaws general extension.

A fin 6 comprises a body provided with at least one hole 8 for the passage of a tube 4 of the heat exchanger 1. This hole is shown in Figure 3 of the present application.

The hole 8 has an outline, here elongated corresponding to the shape of the tube 4 passing through the fin 6. In the embodiment shown here, the contour of the tube 8 comprises two so-called long sides 10 and two so-called small sides 12,

More particularly, the contour of the hole 8 has, here, an oblong shape where each of the two long sides 10 has a concavity. The term "oblong shape" means a shape longer than wide and having at both ends a rounded portion.

The fin 6 further comprises a so-called spacing means 14. The spacing means 14, also called pin, is, here, located on a small side 12 of the contour of the hole 8 for passage of the tube 4. Here, ie spacing means 14 is placed perpendicular to the direction of the air flow F.

In this example, the spacing means 14 extends from the body of the metal band constituting the fin and this in a plane different from the general plane of extension of the fin 6. Here, the spacing means 14 extends substantially perpendicular to the general extension plane of the fin. The spacing means 14 is here made from the material of the fin body 6.

The spacing means 14 is obtained by, in particular, punching and lifting the metal forming the fin 6. During punching, it is expected to leave two strands of material, these two strands are then raised to form the means of spacing 14. The spacing means or collar 14 makes it possible to define the separation step between two adjacent fins of the heat exchange bundle. As a reminder, separation step means the distance separating two fins in the direction of stacking them in the heat exchanger.

According to the invention, the collar 14 further comprises a surface 16 adapted to support another fin.

In other words, the spacing means 14 is provided with an outgrowth 16 extending in a plane different from the plane of extension of the latter. Here, the protrusion or bearing surface 16 of the spacer means extends substantially parallel to the general extension plane of the fin 6. This protrusion allows the maintenance of a regular separation pitch between the fins 6 of the heat exchanger 1.

In other words, a surface 16 adapted to support another fin can be seen as a protuberance unfolding in a plane different from that of the collar 14.

In the embodiment shown, the surface 16 adapted to support another fin is made in the form of a raised edge or tongue 16. In other words, the spacing means 14 has an end connected to the fin 6 and a the distal end of the end connected to the fin 6, the distal end of the spacer means 14 comprises the bearing surface 16, which here extends substantially parallel to the general extension plane of the fin 6.

The tongue 16 is in the extension of the spacing means 14 and is substantially elongate in shape, flat and narrow. The connection between the spacing means 14 and the tongue 16 is effected via, here, a radiated part. In other words, the tongue 16 is connected to the collar 14. In other words, the tongue 16 is made of material material from the spacing means 14 and the body of the fin 6.

The surface 16 adapted to support another fin is obtained by rolling out the two strands of material forming the spacing means 14. This rolling is obtained using a radially punched. A fin 6 according to the invention thus makes it possible to reuse a part of the material which is normally discarded after punching to create the hole S for the tube. It will be noted that this additional material stored on the exchanger and in contact with the tube is only beneficial for heat exchange.

The fin 6 further comprises at least one means 18 capable of disturbing the flow of air F. Here, the means 18 capable of disturbing the flow of air F is produced by louvers parallel to the direction of the air flow. F.

A fin 6 may in particular be obtained by a method comprising at least the following steps:

- The metal strip is punched so as to form the hole 8 for the passage of the tube 4 while retaining two strands of material 14 (step A), the two strands of material 14 are raised with a punch and 'a matrix

(step B)

- The two strands of material 14 are turned towards the outside of hole 8 by means of a radially punched punch (step C) so as to form the surface 16 able to support another fin.

It will be noted that the punching is carried out using punches adapted to the shape of the tube. Here, the punches used have a form called peanuts.

Additional manufacturing steps may be provided in which the height of the strands of material 14 is calibrated to obtain the desired pitch by means of a shaving pile and / or forming transverse slits in order to obtain the average 18 capable of disturbing the flow of air, and / or splitting the metal strip to obtain at least two metal strips.

The invention is not limited to the embodiments described above, only as examples, but encompasses all the variants that may be considered by those skilled in the art within the scope of the claims below. The variants described above can be taken separately or in combination with each other.

Claims

claims A fin (6) for a heat exchanger comprising a body provided with at least one hole (8) for passage of a tube (4) of said heat exchanger (1) and means (14) for spacing the hole (8) having a contour with two said large sides (10) and two said small sides (12), and the spacing means (14) being located on a small side (12) of the contour of the hole ( 8) of passage of the tube (4), characterized in that the spacing means (14) comprises a bearing surface (16) adapted to support another fin. 2, Aiette according to the preceding claim, wherein the bearing surface (16) adapted to support another fin is made of material of said spacer means (14). 3. A fin according to claim 1 or 2, wherein the bearing surface (16) adapted to support another fin is realized in the form of a raised edge (16) substantially parallel to a so-called plane of general extension of the fin. 4. A fin according to claim 1 or 2 further comprising at least one means (18) capable of disturbing a flow of air (F) passing through said fin (6). 5. A fin according to the preceding claim, wherein said means (18) capable of disturbing said air flow is formed by louvers, said louvers being parallel to the direction of said air flow (F). 6. heat exchanger (1) comprising at least one fin (6) according to one of the preceding claims, said fin being traversed by tubes (4) in which circulates a coolant. 7. Heat exchanger according to the preceding claim, wherein the tubes (4) have an oblong shape.