WO2006061485A1 - Fluid reservoir with a tubular wall, particularly for an air-conditioning condenser - Google Patents

Abstract

The invention relates to a fluid reservoir comprising at tubular wall (12) having at least one extremity that is closed by an outer partition wall. The outer partition wall is fixed in the tubular wall at a chosen distance (L) from the edge of the extremity (14) of the tubular wall by means of an adhesive (22) forming a seal. The tubular wall (12) comprises a crimped part (32) located in a region of the edge of the extremity in order to ensure mechanical holding of the capsule.

Description

Tubular wall fluid reservoir, in particular for air conditioning condenser

The invention relates to a fluid reservoir comprising a tubular wall having at least one end closed by a partition.

Such tanks have applications in many industrial fields, one of them being that of air conditioning circuits for motor vehicles. It is known to add a coolant reservoir, also called "bottle", to an air conditioning condenser.

Such a reservoir comprises a tubular wall, usually a circular cylindrical wall made of an aluminum-based material, this wall being closed at its two ends by a shutter member wall.

In this particular application, the tank usually houses filtration means for dividing the interior of the tank into an upstream compartment which receives the condensed refrigerant fluid, unfiltered, and a downstream compartment which receives the refrigerant condensed and filtered. Usually, the tank also houses dehydration means, for example a desiccant cartridge, housed in the upstream compartment of the tank.

This tank, which also serves as an expansion vessel for the refrigerant fluid, is in communication with the condenser itself. For this purpose, the tubular wall usually comprises an inlet orifice which opens into the upstream compartment to admit the condensed refrigerant fluid from the condenser and an outlet opening into the downstream compartment to discharge the filtered fluid to the condenser where it is subcooled.

In most known embodiments, the fluid reservoir is accessible to allow changing the filtration means and / or the dewatering means. The document FR 2 785 043 teaches a condenser tank closed with a screw cap, provided with two O-rings for sealing.

There is also known a condenser reservoir having a tip screwed to a base integrated in the condenser, one sealing being provided by two O-rings mounted around the tip.

Furthermore, solutions are known in which the reservoir is permanently closed, the filtration and dewatering means being non-replaceable.

Thus, document US 2003/0085026 teaches a reservoir integrated in a collector of a condenser, in which an external partition ensures both the closure of the reservoir and that of the collector. Closing and sealing are obtained by brazing the outer wall.

Document US Pat. No. 5,713,217 discloses a tank whose ends are each closed by an external partition, the seal being provided by soldering the partitions.

The document WO 03 056259 discloses a condenser tank, one end of which is closed by a welded pellet in which is fixed a filter cartridge.

Tanks with a removable cap offer the advantage of allowing accessibility to internal components (filtration means and dewatering means) housed in the tank.

However, they have the disadvantage of requiring joints capable of ensuring a perfect seal, which assumes a perfect surface at the range of the joints and grooves having a rigorously controlled roughness.

In the case where the tank is closed by welding, there is a risk of melting plastic parts housed inside the tank. This is particularly the case with filtration that often use a very thin plastic web.

When the tank is equipped with a brazed partition, it requires to integrate the filtration means and the dehydration means before soldering in a brazing furnace. This excludes therefore any piece made of plastic. In addition, this supposes to provide a housing for integrating dehydration means other than a cloth bag or a cartridge.

The object of the invention is in particular to overcome the aforementioned drawbacks.

It aims in particular to provide a fluid reservoir, at least one of the ends can be closed permanently by an external partition ensuring a perfect seal and perfect compatibility with plastic parts housed inside the tank.

It is another object of the invention to provide such a reservoir which finds particular application in air conditioning condensers for motor vehicles.

To this end, the invention proposes a fluid reservoir of the type defined in introduction, in which the external partition is a capsule having a cylindrical periphery fixed in the tubular wall at a selected distance from an end edge of the tubular wall by via a glue seal forming sealing d ^1, and wherein the tubular wall includes a crimped portion in the end edge of the region to ensure a mechanical strength of the capsule.

Thus, one seal between the capsule and the tubular wall is provided by an adhesive, while the mechanical strength of the capsule is provided by a crimped portion. This ensures both a perfect seal and a perfect mechanical strength, without involving a welding or soldering operation. Under these conditions, the tank can safely accommodate plastic parts.

Advantageously, the crimped portion extends from the end edge an axial distance less than the selected distance.

In this way, the crimping takes place on a restricted part of the tubular wall without the risk of deforming the capsule, which would otherwise be detrimental to the seal.

In a preferred embodiment of the invention, the capsule comprises a domed bottom which turns its concavity towards the outside of the tank and which is connected to the cylindrical periphery. This convex bottom advantageously has a torispherical shape.

Preferably, the capsule is a stamped metal part, advantageously an aluminum-based material.

The tubular wall is preferably made by extrusion, preferably from an aluminum-based material.

The glue is advantageously a polymerizable glue chosen from anaerobic type glues, that is to say an adhesive which polymerizes rapidly in the absence of air.

In a preferred embodiment of the invention, the two ends of the tubular wall are each provided with a capsule as defined above.

In a preferred application, the reservoir is arranged to contain a refrigerant fluid of an air conditioning condenser.

In another aspect, the invention relates to a heat exchanger comprising a fluid reservoir as defined above.

In yet another aspect, the invention relates to a method for manufacturing a fluid reservoir comprising a tubular wall, at least one end of which is provided with a partition such that previously defined. This method comprises the following operations

a) providing a partition made in the form of a capsule having a cylindrical periphery adapted to the tubular wall of the tank;

b) introducing the capsule into the tubular wall so that it is at a selected distance from an end edge of the tubular wall;

c) fixing the capsule in the tubular wall by means of a sealing gasket adhesive; and

d) crimping the tubular wall in the region of the end edge to form a crimped portion ensuring the mechanical strength of the capsule.

Operation b) advantageously comprises the introduction of the capsule which has previously received a layer of adhesive on its cylindrical periphery.

Operation c) advantageously comprises the polymerization of a polymerizable adhesive.

For the operation d), two jaws are advantageously used which are brought closer to one another to grip the tubular wall in its end region and form the crimped portion.

Preferably, the two jaws each define a half aperture adapted to the outer section of the tubular wall and having a projecting rib adapted to deform the tubular wall in its end region when the two jaws are close to one another. 'other.

Preferably, the two protruding ribs each have a semicircular shape and together form a calibrated ring when the two jaws are close to one another. In the following description, given by way of example, reference is made to the accompanying drawings, in which:

- Figure 1 is a longitudinal sectional view showing an end of a tubular tank wall and a capsule, before assembly;

- Figure 2 is a view similar to Figure 1 after placing the capsule and before crimping;

- Figure 3 is a view similar to Figure 2 showing a crimping tool;

Figure 4 is a view similar to Figure 3 showing the assembly after crimping;

- Figure 5 is a perspective view showing the end of the tubular wall equipped with the capsule, and a crimping jaw;

- Figure 6 is a view similar to Figure 5 showing the two crimping jaws; and

- Figure 7 schematically shows a condenser provided with a refrigerant reservoir whose two ends are each closed by a capsule according to the invention.

Referring first to Figure 1 which shows a fluid reservoir 10 having a tubular wall 12 which, in the example, is a cylindrical wall of circular section having an internal diameter Dl. This wall, which is partially represented, has an end or an open face delimited by an end edge 14.

The tubular wall 12 is, in the example, made by extrusion, advantageously from an aluminum-based material.

The reservoir 10 may constitute in particular a refrigerant reservoir for a condenser (not shown) of a automotive air conditioning system. In this particular application, the inside diameter D1 of the tubular wall 12 is usually between 15 and 35 mm.

The reservoir is intended to be closed, at least at one of its ends, by an outer partition made here in the form of a capsule 16, shown at a distance from the wall. This capsule 16 is advantageously made in the form of a stamped metal part, for example an aluminum-based material. The capsule 16 has a cylindrical periphery 18 connected to a curved bottom 20 which, in the example, has a torispherical shape. In the example, the periphery 18 has an axial height H which is of the order of 3 mm and an outside diameter D2 which is slightly smaller than the inside diameter D1 of the tubular wall to allow the capsule to be interlocked in the tubular wall. as we will see later.

Before assembly, the cylindrical periphery 18 of the capsule 16 is provided with a layer 22 of an adhesive which, in the example, is a polymerizable adhesive. An adhesive is used that must be compatible with the fluid that will receive the reservoir, ie a refrigerant in the case of a tank associated with an air conditioning condenser.

In the example, the glue used is an anaerobic methacrylate, that is to say a glue suitable for metal surfaces. The deposition of the adhesive layer 22 can be carried out for example with the aid of a brush or with the aid of an automatic gluing device.

In a subsequent step, the capsule 16 is introduced into the tubular wall 12 so that the edge 24 of the capsule is at a selected distance L from the end edge 14 of the tubular wall, as shown in FIG. the particular example considered, the chosen distance L may be of the order of 5 mm.

The adhesive layer 22 allows, by its viscosity, a temporary hold in place of the capsule at the distance L above. The glue is then polymerized at room temperature (25 ° C) 30 ° C), either hot to increase the polymerization rate, for example to 40 ° -50 ° C, by passage in an oven, to ensure a final connection between the periphery of the capsule and the tubular wall forming a seal waterproof.

In a preferred embodiment, a polymerizable glue is used at room temperature. For this, use may in particular glue known under the name Loctite ^® 121078. This is a urethane methacrylate anaerobic is known as usable fixing product in the art.

In a subsequent step, the tubular wall 12 is crimped in the region of the end edge 14 by means of a crimping tool 26 (FIG. 3) having two jaws 28 and 30 that can be brought closer to each other. the other (arrows F1) in a direction perpendicular to the axis XX of the tubular wall. These two jaws, which will be described later, make it possible to shape the tubular wall, in the region of the end edge 14, over an axial distance 1 which is less than the axial distance L, to obtain a crimped portion 32 (FIG. ).

The crimped part 32 makes it possible to tighten the tubular wall, in the region of the end edge 14, to ensure a mechanical strength of the capsule 16. Thus, the seal between the capsule and the tubular wall is effected by the glue 22, while its mechanical resistance is effected by the crimped portion 32. The capsule thus set up is arranged so that the curved bottom 20 turns its concavity towards the outside of the tank, which allows it to withstand significant pressure of the fluid contained later in it.

The jaws 28 and 30 (FIG. 3) delimit respectively two half-openings 34 and 36 adapted to the external section of the tubular wall and having a projecting rib 38, 40 for deforming the tubular wall in its end region, when the jaws 28 and 30 are brought closer to each other.

FIG. 5 shows one of the two jaws, namely the jaw 28, whose half-opening 34 and the rib are visible. 38. The rib 38 is positioned in the region of the end to form the crimped portion. Also shown in Figure 5 the capsule 16 properly placed at a distance from the end edge 14.

Figure 6 is a view similar to Figure 5 which also shows the other jaw 30, the two jaws being shown in the crimping position. The two ribs 38 and 40 together form a calibrated ring when the two jaws are close to one another, the caliber of the ring and its position in the jaws make it possible to perform, very precisely, the crimped portion 32.

Although the polymerization of the adhesive is preferably carried out before crimping, it is conceivable to reverse the order of these two operations.

Referring now to Figure 7 which shows a reservoir 10 according to the invention whose two ends were closed by two capsules 16 of the type defined above. The tank 10 is attached to an air conditioning condenser 40 shown schematically here. The reservoir 10 houses two components which are placed beforehand inside the tank before final closure thereof by the two capsules 16. These two components comprise on the one hand a filter 42 and, on the other hand, a cartridge 44. The filter 42 divides the interior of the tank into an upstream compartment 46 and a downstream compartment 48. The upstream compartment 46 has an inlet 50 which communicates with the condenser and which allows the admission of the cooling fluid. condensed as shown by the arrow F2.

This inlet 50 opens into the upstream compartment 46. The fluid is dehydrated in the upstream compartment 46 which contains the desiccant cartridge 44. The fluid is then filtered by the filter 48 to produce a filtered fluid in the downstream compartment 48. filtered fluid leaves the compartment 48 through an outlet 52 to gain the condenser 40 as shown by the arrow F3. Because the assembly of the two capsules 16 is effected by essentially mechanical processes, without appreciable heat input, as would be the case by a brazing operation, the filter 42 and the desiccant cartridge 44 can be made at least in part. plastic part.

It should be noted that the polymerization of the adhesive is carried out at a moderate temperature, which is generally of the order of 25 ° -30 ° C for a Locticte ^® type adhesive, as mentioned above.

Of course, the invention is not limited to a particular application to refrigerant tanks for air conditioning condensers. It can be used for other types of tanks such as collector boxes for heat exchangers. In addition, it is conceivable that only one end of the tank is closed by a capsule and the other end is closed in another way.

Claims

claims A fluid reservoir comprising a tubular wall (12) having at least one end closed by an outer wall, characterized in that the outer wall is fixed in the tubular wall at a selected distance (L) from an end edge (14) of the tubular wall by means of an adhesive (22) forming a seal, and in that the tubular wall (12) has a crimped portion (32) located in the region of the end edge. to ensure a mechanical strength of the capsule. 2. fluid reservoir according to claim 1, characterized in that the crimped portion (32) extends from the end edge (14) over an axial distance (1) less than the selected distance (L). . 3. Fluid tank according to one of claims 1 and 2, characterized in that said outer wall is a capsule (16), the capsule (16) comprising a curved bottom (20) which turns its concavity outward of the tank (10) and which is connected to a cylindrical periphery (18). 4. Fluid tank according to claim 3, characterized in that the curved bottom (20) of the capsule (16) is torispherical in shape. 5. Fluid tank according to one of claims 1 to 4, characterized in that the capsule (12) is a stamped metal part, preferably an aluminum-based material. 6. Fluid tank according to one of claims 1 to 5, characterized in that the tubular wall (12) is made by extrusion, preferably from an aluminum-based material. 7. Fluid tank according to one of claims 1 to 6, characterized in that the adhesive (22) is a polymerizable adhesive selected from anaerobic type glues. 8. Fluid tank according to one of claims 1 to 7, characterized in that the two ends of the tubular wall (12) are each provided with a capsule (16). 9. Fluid tank according to one of claims 1 to 8, characterized in that it is arranged to contain a refrigerant of an air conditioning condenser. 10. Heat exchanger comprising a tank according to one of claims 1 to 9. 11. A method of manufacturing a fluid reservoir (10) comprising a tubular wall (12) having at least one end provided with a partition (16), as defined in one of claims 1 to 9, characterized in that it includes the following operations: a) providing a partition made in the form of a capsule (16) having a cylindrical periphery (18) adapted to the tubular wall (12) of the reservoir; b) introducing the capsule (16) into the tubular wall (12) to be at a selected distance (L) from an end edge (14) of the tubular wall; c) fixing the capsule in the tubular wall by means of an adhesive (22) forming a seal; and d) crimping the tubular wall (12) in the region of the end edge (14) to form a crimped portion (32) providing the mechanical strength of the capsule (16). 12. The method of claim 10, characterized in that the operation b) comprises the introduction of the capsule (16), which has previously received a layer of adhesive (22) on its cylindrical periphery (18). 13. Method according to one of claims 10 and 11, characterized in that the operation c) comprises the polymerization of a polymerizable adhesive. 14. Method according to one of claims 10 to 12, characterized in that the operation d) comprises the use of two jaws (28, 30) close to one another to grip the tubular wall (12). in its end region and form the crimped portion (32). 15. The method of claim 13, characterized in that the two jaws (28, 30) each define a half-opening (34, 36) adapted to the outer section of the tubular wall and having a projecting rib (38, 40). ) capable of deforming the tubular wall (12) in its end region when the two jaws are close to each other. 16. The method of claim 14, characterized in that the two protruding ribs (38, 40) each have a semi-circular shape and together form a calibrated ring when the two jaws are close to one another.