EP1089043A1 - Condenser comprising a reservoir mounted in a removable and tight way on a base - Google Patents

Abstract

The cooler for motor vehicle air conditioning has a header (2) screwed axially into the base (20) itself brazed onto the cooler manifold (3). The header is connected to the manifold by ducts (31,32) in the base. Threads (13,24) retain the reservoir which is isolated against contact with the coolant by O-rings (15). A sleeve (40) protects the threads from external conditions.

Description

The invention relates to a condenser, in particular for a fluid. refrigerant in a cabin air conditioning system of a motor vehicle, comprising a manifold and an intermediate tank for treatment and / or the accumulation of a fluid, connected to the manifold by connecting pipes.

In such a condenser, as is well known, the tank intermediary can fulfill all or part of the functions following: filtration and / or dehydration of the refrigerant, compensation for variations in the volume thereof, separation of liquid and gas phases. His interposition between an upstream part and a downstream part of the condenser allows only fluid to circulate in the latter in the liquid state, which is thus sub-cooled below the liquid / gas equilibrium temperature, improving condenser performance and making it relatively independent of the quantity of fluid contained in the circuit.

EP-A-0 480 330 describes, in an air conditioning condenser of vehicle, an intermediate tank which is fixed so removable on a base secured to the manifold, crossed by the two connecting pipes. This tank is provided at its lower end with a head secured to its wall, which is fixed to the base by means of a screw. The connecting pipes extend partly into the base and partly in the head of the tank.

This known achievement is relatively complex and cumbersome. In addition, to replace the tank, unscrew the fixing screw, which may include serious difficulties depending on accessibility in the vehicle.

The object of the invention is to remedy these drawbacks, and to propose simple and convenient means for fixing of the tank on the base, while ensuring protection of these fixing means against internal aggressions and outside.

The invention relates in particular to a condenser comprising a box collector and an intermediate tank for treatment and / or the accumulation of a fluid, which binds so removable on a base secured to the manifold, crossed by two connecting pipes for the transfer of fluid between the manifold and the tank.

According to the invention, the reservoir and the base have mating threaded surfaces which cooperate with each other to fixing the tank to the base, at least one joint sealing preventing the fluid contained in the reservoir from come into contact with said threaded surfaces and a added stopper protecting them against external corrosive agents.

• Le joint d'étanchéité est coaxial auxdites surfaces filetées.
• Ledit élément d'arrêt est coaxial auxdites surfaces filetées.
• Ledit élément d'arrêt est une bague élastique serrée axialement entre des surfaces en regard du réservoir et de l'embase.
• L'élément d'arrêt est un manchon recouvrant étroitement deux portions de surface tournées radialement vers l'extérieur appartenant respectivement au réservoir et à l'embase et mutuellement juxtaposées dans la direction axiale, lesdites portions de surfaces étant reliées auxdites surfaces filetées par de courts chemins de fuite.
• Le manchon est emmanché sans jeu sur ladite portion de surface du réservoir et recouvre avec jeu ladite portion de surface de l'embase.
• La surface filetée du réservoir est une surface extérieure reliée à ladite portion de surface du réservoir par un épaulement, la surface filetée et ladite portion de surface de l'embase étant prévues sur les faces intérieure et extérieure d'une paroi annulaire, adjacentes à une extrémité axiale libre de celle-ci.
• Le manchon présente sur sa face intérieure une nervure annulaire pénétrant entre ledit épaulement et ladite extrémité libre.

Optional, complementary or alternative features of the invention are set out below:

• The seal is coaxial with said threaded surfaces.
• Said stop element is coaxial with said threaded surfaces.
• Said stop element is an elastic ring tightened axially between facing surfaces of the reservoir and the base.
• The stop element is a sleeve tightly covering two surface portions facing radially outwards belonging respectively to the reservoir and to the base and mutually juxtaposed in the axial direction, said surface portions being connected to said threaded surfaces by short escape routes.
• The sleeve is fitted without play on said surface portion of the tank and covers with play said surface portion of the base.
• The threaded surface of the reservoir is an outer surface connected to said portion of the surface of the reservoir by a shoulder, the threaded surface and said portion of the surface of the base being provided on the inner and outer faces of an annular wall, adjacent to a free axial end thereof.
• The sleeve has on its inner face an annular rib penetrating between said shoulder and said free end.

The characteristics and advantages of the invention will be described in more detail in the description below, in referring to the attached drawings.

Figure 1 is a front view of a condenser according the invention.

Figures 2 and 3 are views in axial section of the base and from the bottom of the tank, respectively for two embodiments of the condenser.

The condenser 1 shown as a whole in FIG. 1 includes two manifolds 3, 4 vertically elongated and spaced from each other in a horizontal direction, interconnected by a multiplicity of tubes of horizontal fluid circulation 5. Each manifold is divided into different rooms by horizontal partitions 6 so that the fluid circulates in the tubes 5, alternatively from a chamber in box 3 to a chamber of box 4 and vice versa, from the upper chamber of the box 4, which communicates with an inlet pipe 7, up to the lower chamber of the box 3.

One of the intermediate partitions of the manifold 3, designated by the reference 6-1, separates one from the other of the rooms 9-1 and 9-2, located above and below respectively of partition 6-1, and which communicate with each other exclusively via a tank 2, which is elongated vertically and extends along the box 3. Room 9-2 is in turn separated from the lower room of the box, designated by the reference 9-3, by a partition 6-2.

The tank 2, substantially of revolution around an axis vertical A, includes a housing formed by a cylindrical body 10 occupying most of its height, and a pass narrowed 11 arranged at its lower part. Col 11 is at his turn subdivided from top to bottom into three regions 12, 13 and 14 of decreasing diameter linked together by radial shoulders, the intermediate region 13 being provided of a male thread and the lower region 14 being hollowed out two circumferential grooves for the accommodation of two sealing O-rings 15. The neck 11 is crossed by an axial tube 17 which projects upwards at inside the tank and down outside of this one. In the annular volume 18 between the wall side of the body 10 and the tubing 17 are housed substances suitable for filtering and / or dehydrating the fluid circulating in the condenser.

The tank 2 is in mechanical and communication link fluid with the manifold 3 via a base 20. This base is preferably a part cast in aluminum alloy, defining a wall 21 substantially of revolution around the axis A, which delimits a housing 23 open upwards for the neck of the tank 2. The lateral surface of the housing 23 present in a region upper 24 a female thread cooperating with the thread of region 13 of the reservoir to ensure fixation coaxial of the latter on the base. A middle region cylindrical 25 of the wall 21 cooperates with the seals sealing 15, and a cylindrical lower region 26, extending below the free end of the neck 11, surrounds the tubing 17 and delimits an annular space therewith, the free end of which rests on a seat 27 provided at the bottom of the housing 23, by a sealing lip 28. A flange of retaining 33 mechanically connects the upper end of the tank 2 to that of the manifold 3 for a more stable tank attachment.

To the wall 21 is connected externally a veil 29 extending substantially along a plane passing through the axis A. This veil presents, on both sides of this plan, bulges 30 which can accommodate two elongated pipes 31, 32 parallel to this plane. In an intermediate stage of the manufacture of the base, the pipe 31 opens by its two ends respectively in the housing 23, at the aforementioned annular space, and in the free edge of the veil 29, and is inclined upwards from one to the other. The pipe 32 extends horizontally from the free edge of the veil below the housing 23, where it forms an elbow upwards to lead to the bottom of it, inside of the annular seat 27. In the finished base, brazed plugs 35, 36 seal the free ends of the pipes 31, 32 and these open out outside exclusively through open passages in lateral bosses formed on the bulges 30.

The base 20 is fixed to the manifold 3 by soldering the aforementioned lateral bosses on the outer face of the tubular aluminum sheet wall of the box, when assembly of the condenser by brazing. The gentle passages in the side bosses communicate with rooms 9-1 and 9-2 respectively from the box by holes provided in the tubular wall and into which end caps engage provided for this purpose.

The fluid entering through the tubing 7 into the chamber upper of the manifold 4 runs through a first group of tubes according to arrow F1 to reach the chamber upper of the box 3, then two other groups of tubes, according to arrows F2 and F3, to enter the room intermediate of the box 4 and in the room 9-1 of the box 3. The condensed fluid thus reaching the chamber 9-1 passes from it into the annular space 23 of the base by a lateral passage and by the inclined pipe 31, then enters the tank 2, screwed into the base, by the outside of the tube 17. It then crosses the volume annular 18 where it is dried and filtered. The fluid leaves volume 18 via tubing 17, and reaches chamber 9-2 of the manifold 3 by the horizontal pipe 32 and the corresponding lateral passage of the base. So the tubes 5 and the chambers of boxes 3 and 4 located higher than the partition 6-1, including room 9-1, constitutes a section of the condenser traversed by the fluid upstream of the tank, while the tubes and chambers located more that this partition, including room 9-2, constitutes a downstream section. The fluid passes from chamber 9-2 to the lower chamber of the manifold 4 according to the arrow F4, then is routed to room 9-3 according to arrow F5. The fluid leaves this last chamber, and the condenser, through tubing 37.

The O-rings 15 provide a sealed separation between inside and outside of the refrigerant circuit, at the junction between the tank 2 and the base 20. They therefore protect the threaded surfaces 13, 24 against all contact with the fluid. Besides, to protect these same threaded surfaces against external corrosive agents, it is provided, in the embodiment of Figure 2, a sleeve 40, constituted for example by a part molded in plastic material, fixed on the tank by fitting on region 12 of the neck. Sleeve 40 protrudes downward beyond region 12 to cover the face without play outside 19 of the annular wall 21 of the base, at near its free end edge 41. It has a rib 42 projecting radially inwards, between edge 41 and shoulder 43 which connects regions 12 and 13 from the reservoir neck. The sleeve thus forms a baffle between the exterior and the threaded surfaces 13, 24 protecting these against projections.

In the variant of Figure 3, the tank and the base are identical to those of figure 2, the reference signs of their different elements not being repeated. The sleeve 40 is replaced by an elastomer ring 50 surrounding region 13 of the neck, above the thread of this, which can be tightened axially, when screwing the tank, between edge 41 and shoulder 43.

Claims (6)

Condenser (1), especially for a refrigerant in a passenger compartment air conditioning system motor vehicle, comprising a manifold (3) and an intermediate tank (2) for treatment and / or accumulation of a fluid, which removably fixes on a base (20) integral with the manifold, crossed by two connecting pipes (31, 32) for the transfer of the fluid between the manifold and the tank, the tank and the base having surfaces conjugate threads (13, 24) which cooperate with each other to fixing the tank to the base, at least one joint sealing (15) preventing the fluid contained in the reservoir to come into contact with said threaded surfaces and an attached stopper (40) protecting them against external corrosive agents, characterized in that the stopper is a sleeve tightly covering two surface portions (12, 19) facing radially towards the exterior, belonging respectively to the tank and to the base and mutually juxtaposed in the direction axial. The condenser of claim 1, wherein the seal is coaxial with said threaded surfaces. Condenser according to either of Claims 1 and 2, in which said stop member is coaxial with said surfaces threaded. Condenser according to one of the preceding claims, in which the sleeve is fitted without play on said surface portion (12) of the tank and covers with play said surface portion (19) of the base. Condenser according to one of the preceding claims, wherein the threaded surface of the reservoir is a surface outer (13) connected to said surface portion (12) of the tank by a shoulder (43), the threaded surface (24) and said surface portion (19) of the base being provided on the inner and outer faces of an annular wall (21), adjacent to a free axial end (41) thereof. The condenser of claim 5, wherein the sleeve has on its inner face an annular rib (42) penetrating between said shoulder and said end free.

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