EP0270433A1 - Heat exchanger with a header box provided with a partition wall - Google Patents

Abstract

The heat exchanger consists of at least one collecting plate covered by a header box fitted on the inside with at least one longitudinal partition pressed against the collecting plate to form a sealed joint. With two rows of tubes, this defines a heat exchanger with at least two channels in the system. The sealing is provided by a piece of elastomer gripped between the free edge of the partition and the collecting plate. The collecting plate has a longitudinal groove (16) partly filled by a flexible rib (17) itself having a groove (17a) to receive the free edge of the partition (7). Protuberances (18) are formed in order to increase the longitudinal rigidity of the partition (7). <IMAGE>

Description

The present invention relates to a heat exchanger used in particular on motor vehicles for cooling a circulation fluid or heating the air admitted into the passenger compartment of the vehicle.

The invention relates more particularly to heat exchangers with fluid circulation in several passes such as those, for example, more commonly called U-shaped exchangers or two methodical passes

This type of exchanger consists of a bundle of finned tubes provided with at least one fluid box divided internally into two compartments by a partition, one of the compartments, serving for the inlet and the other for the outlet. circulation fluid. Thus, the fluid arrives in the first compartment passes through a first part of the beam in a first direction and then returns to the second compartment having previously crossed the second part of the beam in the opposite direction.

It has been found that the partition delimiting the fluid box in two compartments fails to be connected in a perfectly sealed manner to the collector plate that the fluid box comprises. Likewise, experience has shown that the difference in pressure which prevails between the two compartments and which can reach relatively high values is capable of causing the deformation of said partition and, consequently, of producing leaks between the compartments.

This drawback worsens in the case where the fluid box is divided internally into two compartments by a logitudinal wall of great length.

Similarly in the case where the fluid box is divided internally into three compartments by two transverse partitions, such as for example for a circulation of fluid called quadricircuit, the pressure difference varies in a non-negligible manner from the first compartment to third compartment.

These disadvantages occur sometimes when the exchanger is filled when it is used on a vehicle which includes it, because said filling is frequently carried out by connecting one of the compartments of the fluid box to a source of partial vacuum in order to clear the circulation circuit to which is connected the exchanger at the same time as filling is ensured.

The risks of deformation of the partition also arise when the engine's water pump delivers strongly and the pressure is thus appreciably increased in one of the compartments relative to the other.

The object of the present invention is to remedy these drawbacks by allowing reliable and improved sealing of one or more partitions on the collector plate of the fluid box.

According to the invention, the heat exchanger with at least two methodical passes comprising a bundle of finned tubes and at least one fluid box provided internally with at least one partition bearing sealing against the manifold plate that said box fluid by delimiting at least two compartments, the sealing being ensured by an elastomer part clamped between the free edge of the partition and the collecting plate, is characterized in that the collecting plate has a groove partially filled by a flexible rib having itself a groove for receiving the free edge of the partition and in that, protrusions are formed to increase the rigidity of said partition.

Thanks to this, the partition is mounted in a sealed manner in the groove of the rib and is locked in its position by the protrusions and this whatever the pressure prevailing in the compartments.

According to another characteristic of the invention, the protuberances are formed by ribs of the collector plate.

Therefore, the collector plate being a piece of greater rigidity than the partition, said plate participates in an even more effective manner in blocking the partition.

• - La figure 1 est une coupe-élévation schématique transversale d'un échangeur de chaleur auquel peut s'appliquer l'invention.
• - La figure 2 est une coupe longitudinale partielle à plus grande échelle prise suivant la ligne II-II de la figure 3.
• - La figure 3 est une vue partielle de dessus de l'échangeur de chaleur non muni de sa boîte à fluide.
• - La figure 4 est une coupe très agrandie vue suivant la ligne IV-IV de la figure 3.
• - La figure 5 est une coupe partielle très agrandie vue suivant la ligne V-V de la figure 3.
• Les figure 6 et 7 sont des coupes analogues à la figure 4 illustrant deux variantes.
• - La figure 8 est une vue partielle analogue à la figure 3 illustrant une autre variante.
• - La figure 9 est un plan illustrant la partie d'une plaque collectrice tournée vers la boîte à fluide dans une variante de réalisation.
• - La figure 10 est une coupe prise suivant la ligne X-X de la figure 9.
• - La figure 11 est une coupe prise suivant la ligne XI-XI de la figure 9.

The description which follows will bring out the particular features of the invention with reference to the accompanying drawings, given by way of non-limiting example, in which:

• - Figure 1 is a schematic cross-sectional elevation of a heat exchanger to which the invention can be applied.
• - Figure 2 is a partial longitudinal section on a larger scale taken along line II-II of Figure 3.
• - Figure 3 is a partial top view of the heat exchanger not provided with its fluid box.
• - Figure 4 is a very enlarged section seen along line IV-IV of Figure 3.
• - Figure 5 is a very enlarged partial section seen along line VV of Figure 3.
• Figures 6 and 7 are sections similar to Figure 4 illustrating two variants.
• - Figure 8 is a partial view similar to Figure 3 illustrating another variant.
• - Figure 9 is a plan illustrating the part of a manifold plate facing the fluid box in an alternative embodiment.
• - Figure 10 is a section taken along line XX of Figure 9.
• - Figure 11 is a section taken on the line XI-XI of Figure 9.

In a known manner, the exchanger comprises tubes 1 provided with fins 2. In the case of FIG. 1, the tubes 1 are engaged in manifold plates 3,4 covered by fluid boxes 5,6. The fluid box 5 is provided internally with a longitudinal partition 7. In this way the fluid box 5 is divided into two compartments 8.9.

Nozzles such as 10 and 11 are provided to allow the compartments 8,9 to communicate with a fluid circulation circuit, such as for example the water circulating in the cooling circuit of the engine of the motor vehicle.

Assuming that the circulation of the liquid takes place inside the exchanger, as illustrated by the arrows in FIG. 1, this corresponds to what is known in the art a circulation with several methodical passes, here, for two methodical or U-shaped passes.

The exchanger of FIG. 1 is illustrated with two collector plates and two fluid boxes but this exchanger could only comprise the upper collector plate 3 and the fluid box 5. In the latter case, the tubes 1 would be tubes bent into pins or in U.

Similarly, it could be considered the configuration of Figure 1, but with a transverse arrangement of the partition 7 in the fluid box 5, so as to define two compartments located at the ends of said box.

Figures 2, 4 and 5 show that to ensure the seal between the manifold plate, in particular the manifold plate 3 and the corresponding fluid box, the manifold plate is covered, on its side directed towards the fluid box, by a ply 12 of flexible material of the elastomer type, which is molded to delimit sockets 13 inserted in collars 14 of the collector plate. Likewise, the ply 12 advantageously forms a peripheral seal 15 to ensure sealing with the fluid box.

In the example described in which the exchanger comprises two rows of tubes 1 which can each be formed by the two strands of a pin tube, the collector plate delimits between the two rows of collars 14, 14 a (FIG. 4) a longitudinal groove 16 into which a corresponding flexible rib 17 formed is inserted by the ply 12, this rib forming on the side of the ply 12 facing the fluid box a groove 17 a intended to receive the free edge of the longitudinal partition 7.

When the tube passages 14, 14 a of the collector plate are very close together, for example when the center distance A of the tubes is between 10 and 20 mm and preferably between 17 and 17 mm for tubes 1 of circular section having a diameter ⌀ between 4 and 9mm, preferably between 6 and 7 mm, the depth P of the groove 16 is necessarily small and between 1 and 4 mm, preferably between 2 and 3 mm depending on the nature of the metals used for manufacturing collector plate, for example steel, brass, copper or aluminum.

To take account of the necessarily shallow depth of the groove 16 and even more of the groove 17 a , given that the thickness E of the ply 12 is between 0.5 and 3 mm, preferably between 1 and 2 mm, transverse protrusions 18 are provided which, in the illustrated embodiment, have the shape of a rib extending perpendicular to the groove 17 but whose concavity is opposite, that is to say that the convex part of the protrusions 18 is turned towards the inside of the fluid box.

The protrusions 18 are also formed by stamping and have a depth similar to that of the longitudinal groove 16, that is to say that their depth is between 1 and 4 mm, preferably between 2 and 3 mm.

The sheet 12 is shaped, as illustrated in the drawing, to match the protrusions which extend to the immediate vicinity of the groove 16 and which may possibly be formed only up to the vicinity of this groove 16 which ensures wedging of the two lateral edges of the partition 7 which is thus centered.

The space e between the geometric axes of two successive protuberances is between 10 and 25 mm preferably between 15 and 20 mm when the tubes themselves have a diameter between 4 and 9 mm, preferably between 6 and 7 mm, as explained in the foregoing.

According to the variant of FIG. 6, the protuberances consist of extra thicknesses 19 formed by the ply 12. As illustrated in the drawing, the extra thicknesses 19 are higher between two rows of tubes than between two tubes of the same row for that the upper flange 20 formed by the ply 12 around each tube 1 is not affected by said excess thickness. The extra thicknesses 19 of the ply 12 can be combined with the protrusions 18 of the collector plate.

FIG. 7 illustrates another variant according to which protrusions are constituted by projecting ribs 21 directly formed from the partition 7 and placed so as to come to bear against part 1 has tubes 1 which protrudes above the flanges upper 20 of the sheet 12. As in the previous example, the ribs 21 can be implemented in conjunction with the protrusions 18 of the collector plate.

FIG. 8 illustrates yet another variant according to which the longitudinal groove 16 of the collector plate has a wavy shape. In this case, the rib 17 of the ply 12 is also corrugated and the protrusions 18 already described may or may not be used, the partition 7 of the fluid box 5 is produced to have the same corrugations as the groove 16 which has the effect of increasing its rigidity. In addition, the corrugated shape of the groove 16 formed in the collector plate substantially increases its axial bending moment relative to a straight groove.

An additional variant is illustrated in FIGS. 9 to 11 according to which, to increase the axial bending moment of the manifold plate, stiffening grooves 22 deeper than the longitudinal groove 16. The grooves 22 do not affect the sealing since they are covered by the flexible sheet 12. The grooves 22 are formed between the rows of tube passage 14, 14 a and provide free areas 23, 23 a at regular intervals in which protuberances 24, 24 a are formed facing each other in the same manner as the protrusions 18 of FIGS. 3 and 4.

The invention is not limited to the embodiments shown and described in detail, since various modifications can be made thereto without departing from its scope.

Claims (12)

1) Heat exchanger with at least two methodical passes comprising a bundle of tubes (1) with fins (2) and at least one fluid box (5) internally provided with at least one partition (7) bearing sealing against the collector plate (3) that comprises said fluid box by delimiting at least two compartments (8, 9), the seal being ensured by an elastomer part (12) clamped between the free edge of the partition (7) and the collector plate (3), characterized in that the collector plate (3) has a groove (16) partially filled by a flexible rib (17) itself having a groove (17a) for receiving the free edge of the partition (7 ) and in that, protrusions (18, 19, 21) are formed to increase the rigidity of said partition. 2) Heat exchanger according to claim 1, characterized in that the protrusions are formed by
ribs (18) from the collector plate (7) and arranged transversely to the partition (7). 3) Exchanger according to one of claims 1 or 2, characterized in that the protrusions are formed by ribs (21) from the partition (7) being arranged transversely thereto and coming to bear against the part ( 1 a ) tubes (1). 4) Heat exchanger according to one of claims 1 to 3, characterized in that the protrusions are formed by thickeners (19) from the elastomer part (12) covering the header plate (3). 5) Heat exchanger according to one of claims 1 to 4, characterized in that the entire surface of the collector plate (3) facing the inside of the fluid box (5) is covered by a sheet of flexible material (12) of the elastomer type, which is preformed to match at least the bottom of said plate. 6) Heat exchanger according to one of claims 1 to 5, characterized in that the groove (16) is corrugated as is the partition (7). 7) Heat exchanger according to one of claims 1 to 6, characterized in that the manifold plate (3) has stiffening grooves (22) extending transversely to the groove (16) and having a depth greater than the groove (16). 8) Heat exchanger according to one of claims 1 to 7, characterized in that the stiffening grooves (22) provide areas (23, 23 a ) in which protuberances (24, 24 a ) protrude. 9) Exchanger according to one of claims 1 to 8, characterized in that the diameter of the tubes (1) is between 4 and 9 mm, preferably between 6 and 7 mm, the center distance A separating the tubes of two rows is between 10 and 20 mm, preferably between 15 and 17 mm and the depth of the groove (16) is between 1 and 4 mm, preferably between 2 and 3 mm. 10) Exchanger according to one of claims 1 to 9, characterized in that the protrusions protrude by a measurement of between 1 and 4 mm, preferably between 2 and 3 mm when the longitudinal groove (16) makes itself projection of a measurement between the same limits as those relating to said protuberances. 11) Exchanger according to one of claims 1 to 10 characterized in that the thickness of the sheet of flexible material of the elastomer type is between 0.5 and 3 mm, preferably between 1 and 2 mm when the depth of the longitudinal groove and that of the protrusions are between 1 and 4 mm, preferably between 2 and 3 mm. 12) Exchanger according to one of claims 1 to 11, characterized in that the space e separating the geometric axes of two contiguous protrusions is between 10 and 25 mm, preferably between 15 and 20 mm when the diameter ⌀ of the tubes is between 4 and 9 mm, preferably between 6 and 7 mm.

Images