Condenser for air-conditioning systems for vehicles

Abstract

 A condenser for air-conditioning systems for vehicles, comprising:

• a pair of mutually parallel tubular distributors (12);
• a heat-exchange core (14) with tubes (16) and fins (18), set between the aforesaid distributors (12); and
• a tubular container (22) set parallel to one of said distributors (12) and in fluid communication therewith.

The aforesaid tubular container (22) comprises a saddle-shaped fixing part (24) having a cylindrical surface (26) fixed by means of brazing to a corresponding portion of the outer cylindrical surface of the distributor (12).

Description

[0001] The present invention relates to a condenser for air-conditioning systems for vehicles. More precisely, the invention relates to a condenser of the type comprising:

• a pair of mutually parallel tubular distributors;
• a heat-exchange core with tubes and fins, set between the aforesaid distributors; and
• a tubular container extending parallel to one of said distributors and set in fluid communication therewith.

[0002] The aforesaid tubular container is designed to contain a dehydrating granular material that enables elimination of any traces of liquid in the gas flow coming out of the condenser. Recently, a wide range of solutions have been proposed of condensers in which the container for the dehydrating material is made integrally with the corresponding distributor. In particular, the document EP-A-668986 describes a condenser for an air-conditioning system for a vehicle, comprising a manifold element with a double tube with a longitudinal wall of separation which defines two tubular spaces, one of which forms the distributor and the other of which forms the container for the dehydrating material.

[0003] Currently, manufacturers of heat exchangers use various methods for making a condenser with integrated container for the dehydrating material, i.e., applied directly to the tubular distributor. The methods currently adopted may be subdivided into two categories according to whether the tubular distributor is a monolithic component or else is made up of two parts or half-shells. In the case where the tubular distributor is made up of two parts or half-shells, it is possible to proceed from inside the distributor to carry out fixing of the tubular container to the distributor. The situation is, instead, more complex in the case where the tubular container for the dehydrating material is to be applied to a monolithic tubular distributor. Some known solutions envisage the use of additional elements (sleeves, plated sheets, etc.) between the distributor and the container for obtaining their joining by brazing.

[0004] The purpose of the present invention is to provide a simple, inexpensive and reliable solution for application of the tubular container to the distributor in the case where the distributor is made of a monolithic tubular element.

[0005] According to the present invention, the above purpose is achieved by a condenser having the characteristics that form the subject of the main claim.

[0006] The present invention will now be described in detail with reference to the attached drawings, which are provided purely by way of non-limiting example and in which:

• Figure 1 is a partial perspective view of a condenser according to the present invention;
• Figure 2 is a longitudinal section of the distributor-container assembly indicated by the arrow II in Figure 1;
• Figure 3 is a cross section at a larger scale of the part indicated by the arrow III in Figure 2;
• Figure 4 is a schematic perspective view of the tubular container used in the heat exchanger according to the present invention; and
• Figure 5 is a front view of the part indicated by the arrow V in Figure 4;

[0007] With reference to Figure 1, number 10 designates a part of a heat exchanger according to the present invention. The condenser comprises a pair of tubular distributors 12 which are parallel to one another (just one of which is to be seen in Figure 1), between which is set a heat-exchanger core 14 including, in a way of itself known, a plurality of tubes 16 with a flat cross section, between which are arranged undulated fins 18. The ends of the tubes 16 are set in fluid communication with the internal space of the distributors by means of through holes 20 formed in the side wall of the distributor 12.

[0008] The condenser 10 comprises a tubular container 22 fixed to the external lateral surface of the distributor 12. The tubular container 22 is designed to contain a dehydrating material that is able to eliminate traces of liquid from the flow of gas that comes out of the condenser. The tubular container 22 is an extruded aluminium alloy element and has on its outer surface a saddle-shaped fixing part 24 (see Figure 4). The fixing part 24 has a cylindrical surface 26 having the same diameter as the outer cylindrical surface of the distributor 12 in such a way that there exists a contact surface extending between the distributor 12 and the tubular container 22.

[0009] With reference to Figures 2 to 5, the tubular distributor 12 is provided with a pair of through openings 28, 30 aligned to corresponding openings 32, 34 formed in the wall of the tubular container 22. Through the aligned openings 28, 32 and 30, 34 a fluid communication is set up between the distributor 12 and the tubular container 22. Preferably, the tubular container 22 is provided with two projecting portions 36 set at the through openings 32, 34 and designed to engage corresponding recesses 38 formed in the wall of the distributor 12, with the aim of establishing a geometrical reference that enables mutual alignment in a longitudinal direction of the tubular container 22 and the distributor 12. In particular, in the condition in which the projecting portions 36 engage the recesses 38, the openings 28, 32 and 30, 34 are properly aligned with respect to one another. The projecting portions 36 are preferably formed by plastic deformation of the wall of the tubular container 22.

[0010] The distributor 12 is preferably obtained by means of rolling and longitudinal welding starting from a rolled sheet of aluminium having on its outer surface a layer of brazing alloy. The tubular condenser 22 is fixed in a preliminary fashion to the distributor 12 by arc welding or else by riveting. After this preliminary tack weld and after insertion of the ends of the tubes in the slits 20 of the distributor 12, the condenser is subjected to a furnace-brazing step during which fixing together of the various components is obtained. In particular, during the brazing operation definitive fixing of the tubular container 22 to the distributor 12. This fixing operation is carried out along the entire cylindrical contact surface 26 of the saddle-shaped fixing portion 24.

[0011] It will be understood that the system according to the present invention enables a particularly firm and stable fixing to be achieved between the tubular container 22 and the distributor 12, thanks to the large mutual-contact surface. The system according to the present invention is characterized by a considerable simplicity in as much as it does not entail the use of auxiliary fixing elements for achieving joining between the tubular container 22 and the distributor 12. The solution according to the present invention involves a low cost, enables the tubular container 22 to be made in a particularly simple way, and entails a small number of components.

Claims

1. A condenser for air-conditioning systems for vehicles, comprising:

- a pair of mutually parallel tubular distributors (12) ;

- a heat-exchange core (14) with tubes (16) and fins (18), set between the aforesaid distributors (12); and

- a tubular container (22) set parallel to one of said distributors (12) and in fluid communication therewith.

   characterized in that the aforesaid tubular container (22) comprises a saddle-shaped fixing part (24) having a cylindrical surface (26) fixed by means of brazing to a corresponding portion of the outer cylindrical surface of the distributor (12)

2. The condenser according to Claim 1, characterized in that the aforesaid tubular container (22) is obtained by extrusion.

3. The condenser according to Claim 1, characterized in that the aforesaid distributor (12) is a tubular element obtained by rolling and bending of a rolled sheet having a layer of brazing alloy on its outer surface.

4. The condenser according to Claim 1, characterized in that the aforesaid distributor (12) and the tubular element (22) are provided with respective aligned holes of intercommunication (28, 33; 30, 34) and of geometrical-reference means (36, 38) designed to define a relative position between the distributor (12) and the tubular container (22) in which the aforesaid communication holes are aligned with respect to one another.

5. The condenser according to Claim 4, characterized in that the aforesaid reference means (36, 38) comprise a pair of projecting portions (36) co-operating with respective recesses (38).

6. The condenser according to Claim 5, characterized in that the aforesaid projecting portions (36) are obtained by deformation of a wall portion of said tubular container (22).

Drawing