ES2319610T3 - EVAPORATOR OF AIR CONDITIONING SYSTEM. - Google Patents

Abstract

The invention concerns an automotive air conditioning system evaporator (2) with an extended collector (4), whose collector cover is rounded for stability under pressure, divided internally across the collector into a first and a second compartment (8, 10), which are associated with an inlet and outlet for the evaporator coolant, and which exhibits divided transverse slots along its length, common to both compartments, in which is provided a flat pipe array (20), constructed for dual flow as a minimum, linked with each other by means of zigzag fins for the purpose of heat transfer, whose ends are at any given time inserted into a transverse slot in the collector cover in such a way, that one flow (22) in the flat pipes communicates with one compartment and the other flow (24) in the flat pipes (20) communicates with the other compartment. The invention provides for the first or second wall (32, 34) of both compartments (8, 10) formed by the collector cover at any given time to be configured as a rounded tube for pressure stability. <IMAGE>

Description

Evaporator of air conditioning system.

The invention concerns a system evaporator of car air conditioning.

From US-A5 174 373, it know an air conditioning heat exchanger for car presenting a collector that extends longitudinally, which defines a first and a second compartment, each of which comprises a coolant inlet or respectively a refrigerant outlet respectively, the manifold defining a plurality of slots that extend each in both of these compartments, a plurality of pipes that extend from the grooves up to a flow return device, which is appropriate for a condenser.

The pipes in the heat exchange medium external, usually the air surrounding the vehicle, are arranged in series in conventional heat exchangers, similarly than the evaporator in the invention. Keeping in mind the demands of material and space savings that can be satisfied from this mode, optimization attempts for pressure have already been made internal by giving the outer profile of the collector a circular shape. There is, however, no optimization for internal pressure in the case of both semicircular compartments that extend to along the collector and that complement each other transversely.

On the one hand, there are evaporators whose structure includes a plurality of identical rows of tubes flattened Each of the rows is slightly separated from the Other adjacent rows. In the evaporator mentioned in EP 0 325 844 A1, the upper and lower manifolds comprise a plurality of elongated end tubes. The flattened tubes communicate their fluids with the inside of the upper and lower end tubes thus establishing a fluid communication between the two extremes These evaporator structures are not optimized since the view of the installation volumes.

On the other hand, there are exchangers of conventional duplex heat in which two rows of flat pipe assemblies one behind the other with room for allow air circulation, connected to the fluid of internal heat exchange via form pipe collectors circular, where the collectors for these heat exchangers Conventional duplexes have a circular cross section free of cross-sectional subdivisions. In the heat exchanger duplex cited in EP 0 414 433 A2, both rows of the set of flattened pipes may be interconnected with one another several modes by means of connection ducts. This is taken also in the case of its use as an evaporator. In the case of another conventional duplex heat exchanger, such as is specified in SDR 91 11 412. 8 U1, both sets of pipes flattened, arranged one behind the other in the surrounding air, they are fed by different internal exchange fluids of heat, for example on the one hand by means of the cooling water in an engine cooling system and, on the other hand, by means of forced air or motor oil that acts as a coolant in a car air conditioning system. Even in those conventional duplex heat exchangers, in which no has taken into account its use as evaporators, the collectors  they are not subdivided transversely into two successive compartments, isolated from each other by means of a longitudinal divider.

An embodiment of the invention provides an evaporator of air conditioning system for car with only one row of pipes, therefore a simple evaporator that, with both manufacturing depth for the pipes in the circulating air as the working pressure of the predetermined refrigerant, it has the smallest dimensions possible from the point of view of installation volumes and wall thicknesses and, because of that, it also employs the smallest amount of material In addition, for optimization, you must lend special attention to the fact that, in this type of evaporator, the inside of the collector is divided transversely into two Different compartments In the case where there is a number constant of flows in the evaporator (of at least capacity of double flow), coolant flow inlet and return of flow to both compartments are arranged to be made of simultaneous mode while, in the case where there is a number non-constant flows, input flow and flow can be provided back to the same compartment, however, in association with different interior areas that, in the same compartment, are separated from each other by means of at least one partition cross.

Duplex heat exchangers are enough to start to meet the requirements of the definition of problem stated above, especially in the context of optimize manufacturing volumes, even if both sets of flat pipes comprise fins that pass through them (for example, Figs. 16 and 17 of EP 0 414 433 A2).

According to the invention, an evaporator is provided of air conditioning system according to claim 1.

Thus with an evaporator built with a simple arrangement of its flat pipe assembly, each of the two collector compartments is rounded by issues of stability under pressure and in the ideal case it is also circular in cross section. Its operation, according to the invention, it also becomes correspondingly obvious, if a section total circular cross section of a collector as specified in US 5 174 373 is compared with a cross section individual circular of a collector according to the invention, given the two requirements that both circular cross sections of both compartments are identical and must measure the same construction depth than flattened pipes. It follows of that, in the invention, a circular cross section of a individual compartment is about half the diameter of the circular cross section of the complete manifold as it is specified in US 5 174 373. For an internal pressure identical, the reduction in the diameter of the cross section circular corresponds to a factor of two, as well as maybe one reduction of wall thickness to half its value. Of this mode, material and cost savings are already achieved. Also I know achieves a considerable saving in height of the set, which of Anyway, there is hardly any space behind the panel instruments inside the vehicle.

Currently, refrigerants such as R134a widely used are still used for system evaporators of air conditioning for cars, whose pressure of operation is in the region of 10 to 30 bars. exist considerations, in matters of environmental protection, for use natural refrigerants such as CO2, which used in evaporators at operating pressures from 40 to 80 pubs. It has been shown that the evaporator as specified in the invention it also adapts well to work with CO2 as a refrigerant, while saving on wall thickness is it makes particularly and reassuringly evident. Is even possible to install the evaporator as specified in the invention using conventional refrigerants, not assuming a considerable cost increase and no type of rework for a post-operation conversion with CO2

From the perspective of manufacturing and resistance is preferred an integral construction piece for the first wall, the second wall and / or an integral union of both walls and naturally favored by impact extrusion, diecast or hot extrusion. From DE-G 91 11 412.8 U1, a construction is known integral with a first circular pipe and a second pipe circular for the construction of a collector for an exchanger of duplex heat, in particular in Fig. 4 with its description. In this integral conventional construction, the longitudinal divider between both compartments of circular cross section is manufactures from the beginning as an integral component. This concept can also be moved to the simplex evaporator such as It is specified in the invention. The invention is an alternative design.  which provides an integral component with a longitudinal groove, to which an additional component is added outside to form a longitudinal divider between both compartments. The utilization of that additional component, which of course is introduced by a transverse groove, allows both compartments to remain sealed tightly against the front face of the flat pipe introduced in a particularly advantageous manner in any moment and is otherwise common to both compartments in Fig. 4 of DE-G 91 11 412.8 U1. If, in addition, the divisor longitudinal introduced as an additional component is formed perhaps from a sheet of sheet metal previously coated with welding material, it is possible to use the welding furnace to weld that sheet easily to the side face of the pipe flat in the case of performing a strong welding of a Aluminum or aluminum alloy construction.

For precise groove fabrication transversal so that they match the external profile of the flat pipes in the context of acceptable tolerances, it is possible weld flat pipes directly into grooves cross-sections of the relevant component. However, this requires an additional welding application, perhaps by projection by plasma, as expected in the case of DE-G 91 11 412.8 U1 (Fig. 4, reference mark 75).

An alternative design form is preferred in the one that introductory slots, which match the profile of the flat pipes in the context of maximum allowable tolerances, are manufactured as a separate cover component, in which it you can get the adjustment in a much simpler way than in the case  from a built-in manifold or even to a component wall built-in A cover component like that can be formed to starting from sheet metal in a simpler way and then bends properly. If that sheet is coated then with material from welding, a welding support is obtained at the same time for weld the flattened pipes to the collector. It can also be manufactured without difficulty a typical roof component formed of sheet sheet, with collars that extend inside and / or in the outside of the introduction slots and allow welding form a surface joint between the inner surface of the collars and external surfaces of flat pipes. In addition, it is possible to make the grooves manufacturing transverse in the same collector with a lower requirement precision without deteriorating the final result. For example, it is it is possible to trim the transversal grooves with simple milling after extrusion or a comprehensive manufacturing process Similary.

In the simplex heat exchanger in the US 5 174 373, from which the invention originates, as well as in the duplex heat exchanger in EP 0 414 433 A2 as well as in DE-G 91 11 412.8 U1, the dimensions of the transverse groove in the manifold at a given time extended only partially along the internal diameter of the cross section of the circular pipe. In the context of problem described by the invention, instead, not only the complete drainage of this cross section of the internal pipe, but also extend along the length of the groove transverse at any given moment and, with this, the length of the relevant flat pipe in the direction of air flow surrounding that provides heat exchange fluid External in the vehicle. At the same time, in addition, the compartments in the flat pipe through which the heat exchange fluid circulates internal should be, as far as possible, capable of use even the region of the wall thickness of the divider longitudinally, in a different way from US Patent 5 174 373. It proposes another solution in reference to the area of wall thickness of this longitudinal divider, as well as a solution with respect to a extension of the transverse groove in the thickness of the same wall of the collector. Using a milling machine, a simpler method to manufacture the transverse groove, it is possible to take both previous requirements in a particularly simple way. In addition, it is important that, in the groove regions transversal, which are also facing the same area manifold wall and / or longitudinal divider on the front face of each pipe, an internal recess of the groove is made transverse, so that at that point you can get a uninterrupted communication between the relevant compartment in the manifold and critical flat pipe compartments mentioned. A precise adjustment is also invariably achieved. with flat pipes by means of the cover component with its mechanized introduction slots. It has been shown that extremely narrow transverse groove dimensions in the manifold lid, in association with the cover component installed and flat pipes introduced, do not affect so adverse wall thickness sizing requirements of the collector, since any weakness of the material on the wall of the collector is compensated again by the additional use of the parts introduced and the welding used.

Finally, circuits can also be used conventional in the evaporator as specified in the invention, in which, in particular, both compartments can Divide into sub-compartments along the collector.

Modes of embodiment of the invention only by way of examples, in reference to the figures in annex, in which:

Figure 1 shows a cross section to through an evaporator as specified in the invention;

Figures 2, 2a, 3 and 3a show on a scale increased partial cross sections of the collector area to through different variants of an evaporator as it has been specified in the invention, where Fig. 3 develops the form of design shown in Fig. 1;

Figure 2, 3 and 3a are part of the invention.

Figure 4 shows a longitudinal section partial through a variant of the collector as it has been specified in Figures 2 and 3 as well as

Figures 5 and 5a show each, a longitudinal section through the collector of an evaporator such as specified in the invention, seen along the pipes flat, and naturally as two variants, namely configurations triple flow circuit (Fig. 5) and quadruple flow (Fig. 5a).

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In the different figures, the same numerals Reference refers to the same parts.

Fig. 1 shows the basic construction of a evaporator 2 of a car air conditioning system double flow as specified in the invention. It is preferable produce the complete evaporator (or parts thereof) using aluminum or aluminum alloys such as AlMn1 and welded components, for example by means of brazing using AlSi7-12.

The evaporator 2 comprises a set 20 of flat pipes, interconnected by means of fins 21 in zigzag (Fig. 4) for heat transfer purposes. In general, each flat pipe 20 outside the assembly is provided with a zigzag fin, which can be followed externally by a sheet of finishing metal (not illustrated) that can be part of a frame for the set. It is preferable to connect heat exchange at the same time by means of strong welding from zigzag fins 21 to flat pipes 20 and, if necessary, to each metal sheet finish. 20 flat pipes they are arranged in the set primarily at intervals equal and, when installed in the air conditioning system of car, arranged primarily in vertical view schematic of Fig. 1. In addition, the surrounding air circulates mainly as an external heat exchange medium in the horizontal plane as shown in the schematic view of Fig. 1 as specified with the double arrows in continuous line in Fig. 5 and Fig. 5a. The refrigerant that acts as the means of Internal heat exchange is fed according to a double flow to through each of the flat pipes 20, where the arrows painted in Fig. 1 indicate the two flows 22 and 24, namely Flow 22 in the inlet flow part with the arrow pointing down in Fig. 1 and Flow 24 in the outflow part with the arrow pointing up in Fig. 1. A plurality or multiplicity of channels 26 along the transverse length complete each of the flat pipes 20 along the which divide the two flows, for example at any time given, an identical number of channels is assigned to each stream 22 or 24 26.

The same ends 23 of the flat pipes 20 they communicate with the inside of a collector 4, which extends towards the exterior at a 90 degree angle to the pipes flat 20 (compare Figures 4 to 5a); in its transverse direction (schematic view in Figures 1 to 3a), the manifold 4 is divided into two compartments 8 and 10, which are completely, or at least to a considerable extent, separated from each other by means of an intermediate partition 12.

In addition, the manifold lid 6 forms a base of pipe or contributes to its formation. For this purpose, the cover of manifold 6 is divided along its length, in the dimension in which the set of flat pipes 20 is divided, mainly at intervals that are constantly separated by grooves transversal 18 which are common to both compartments 8 and 10, in which each flat pipe 20 in the set of flat pipes 20 introduces its end referenced equally 23 for the purpose to seal it This end 23 of the flat pipe 20 is therefore so, in the same way as the transverse groove 18, common to both compartments 8 and 10. The front faces of the ends 23 of the flat pipes 20 are at the same time aligned to what lengths of both of each of the flat pipes 20 as of collector 4.

The other ends of the flat pipes 20, whose front faces are aligned along the lengths of each of the flat pipes as well as the manifold, are attached to a flow return device 28, which exchange the first flow 22 for the second flow 24 in each individual flat pipe 20. There are numerous alternatives to design for a flow return device 28 like that. Without no limitation to generality, this is formed in Fig. 1 as the receptacle 30 which, with its side wall 31, is pressed as indicated in Fig. 1, keeping the exterior of each fixed flat tube 20. In addition, each flat pipe 20 can be attached to a individual receptacle 30. It is also possible to interconnect those receptacles or build the appropriate receptacle with the structure return flow in a single integral component. Essentially, its function is the return of the two flows 22 and 24 in each tube plane 20.

In evaporator 2, the refrigerant used as internal heat exchange fluid is fed as a opposite transverse flow with respect to the flow direction of surrounding air. This is evident in Figs. 5 and 5a, where the coolant flow direction is illustrated with the arrows horizontally aligned double wall. In this connection, the coolant inlet 14 of manifold 4 and outlet of refrigerant 16 of manifold 4 are formed at any time on an opposite sealing wall 15 or 17 of the manifold 4, for example as illustrated, as an external connection fitting on a wall of sealed with disk form 15 or 17, which is locked attached to manifold cover 6. In Fig. 5, inlet 14 and outlet 16 are joined at the same time with the same sealing wall 15 while, in the design form shown in Fig. 5a, the inlet 14 is attached to a sealing wall 15 and outlet 16 is attached to another sealing wall 17. In both cases the entrance 14 carries to compartment 10, facing away from the direction of the refrigerant flow and outlet 16 comes from the compartment 8, looking towards the surrounding air in circulation.

In addition, both compartments 8 and 10 in any At any given time, two sub-compartments 50 and 52 or 54 and 56 are divided by means of a transverse partition 9 where, in the case of Fig. 5, entry 14 extends through the partition transverse 9 in compartment 10 via a pipe connection 13 intermediate.

The basic principle of using the refrigerant to produce the flow through evaporator 2 is represented in Fig. 1. The refrigerant that has entered compartment 8, as is specified in the design depicted in Fig. 1, is directed to the appropriate flat pipe 20 along the first flow 22 by means of the first halves of channels 26, then changed in from flow return device 28 and directed in the opposite direction back to compartment 6 through the second halves of channels 26. If this flow direction is planned along of the entire length of the evaporator, Fig. 1 with a transverse flow opposite taken as the basis should be a prerequisite for the flow of surrounding air on the right side in the schematic diagram. In a preferred development, however, can also be achieved by means of a type of flow as specified in Figures 5 and 5th for example.

In the arrangement shown in Fig. 5, the refrigerant entering through inlet 14 first enters a sub-compartment 52 of compartment 10, then through of associated flat pipes 20 in sub-compartment 56 of the compartment 8, from it through the flat pipes associates 20 in sub-compartment 50, again in the compartment 10, and finally once again via flat pipes  associated 20 through sub-compartment 54 again from the compartment 8 at exit 16. In this way, all the length of manifold 4, although input 14 and output 16 are placed on the same front face of the manifold 4.

In the design form as specified in Fig. 5a, a corresponding progressive flow is generated along from manifold 4 from input 14 to output 16; first since entrance 14 to sub-compartment 50, from it via the pipes associated or common flat 20 to sub-compartment 54. From here, via associated or common flat pipes 20 to the sub-compartment 52 and finally from here via the associated flat pipes or common 20 to subcompartment 56, which is connected to the output 16.

In addition, it is common to Figures 5 and 5a the fact that, in both compartments 8 and 10 of manifold 4, of the type that they are subdivided into subcompartments (50 to 56) that are displaced with respect to each other from one compartment to another, the refrigerant in evaporator 2 is directed from one side to the other between compartments 8 and 10 along the length of the collector 4.

It is also clear from the illustrations in Figures 5 and 5a that the number of flat pipes  20 associated to each sub-compartment can be chosen so different according to the requirements, just as it would be in principle possible to vary the number of channels 26 in the pipes common flat that reach a couple of subcompartments in any given moment

The following type of construction for each Collector 4 is common to all forms of evaporator 2 design: when developing the conventional design, namely that the cover of manifold 6 has a rounded shape for stability under pressure, this concept applies to both walls 32 and 34 of the first compartment 8 as well as the second compartment 10 of the collector lid Correspondingly, both walls 32 and 34 are each surrounded to achieve stability under pressure, or respectively even rounded to a circular shape in the Design examples

Both forms of design in Figures 2 and 2a They also show two limit cases of this design.

Figure 2 also shows the purest form of a borderline case, in which both walls 32 and 34 are formed as a single integral component 44, which, in addition, even incorporates the intermediate partition 12 between both compartments 8 and 10. The intermediate partition 12 narrows, also forming a point in the direction of adjacent ends 23 of flat pipes 20. The end of this tip may also, depending on the requirement, present the shape of a wedge that moves towards a tip or flatten more or less according to the style of a narrow face of a flat cross panel.

Figure 2a also shows the other case boundary, where both walls 32 and 34 are made respectively  as a single integral component, in which both components, to know walls 32 and 34, are joined by an additional component interleaved separately as a longitudinal divider 36, in this case in the form of a transverse panel of flat material 36, which on the other hand it forms the intermediate partition 12 between compartments 8 and 10. While, in the first case limit shown in Fig. 2, the outer profile of both walls 32 and 34 can be done completely rounded - in which case they are possible extreme deviations of the circular shape - in case 2a both flat faces of the additional component are present, so therefore, preferably opposed to the cross-sectional panel of material flat 36, flattened sections 40 of flange type of an element exterior 36-shaped socket placed in the installation between both walls 32 and 34. Furthermore, it is possible, with or without this socket assembly, provide both outer sides of walls 32 and 34 of flattened sections 40 of the flange type in the same way, for example to mount a manifold 4 from more than two walls 32, 34 etc. These additional flattened sections 40 are depicted in Fig. 2a to illustrate the alternative without adding an accessory with socket shape.

Figures 3 and 3a show a favorable mixture between the two limit cases cited above. From the limit case of Fig. 2, it is further assumed that both walls 32 and 34 are made to from a single integral component 44. It is retained from the boundary case of Fig. 2a intermediate partition 12, made to from an additional component, again in this example with the shape of a transverse panel of flat material 36. In addition, this Additional component 36 is enclosed in solidarity, namely in general by welding, outside, in a groove longitudinal 46 between both rounded curves of the first and second walls 32 and 34, on one side of the manifold 4 looking in opposite direction to the set of flat pipes 20.

The type of interaction with the partition intermediate 12 or a longitudinal divider inserted separately in that position it is also illustrated with the help of two alternatives preferred. It should be noted that both alternatives of interaction and both different designs to create the partition intermediate 12 described above - with or without a divider additional longitudinal 36 - depending on the requirement, they are completely interchangeable.

The first alternative is illustrated in the forms design in Figures 1 and 3 using a longitudinal divider 36 introduced as an additional component, but could also be performed correspondingly with intermediate partition 12 incorporated into integral component 44 as specified in Fig. 2, particularly in the configuration in which there is a tip shaped narrowing. In this way, the partition intermediate 12 is introduced as if it were a flow in a channel 26a which is not used and, in addition, it is fixed in solidarity between its Two channel walls. As represented in schematic format in Figures 1 and 3, this channel 26a, properly used only to divide the flow, it has one more channel width narrows than the remaining channels 26 of each flat pipe 20 to Unless it is essential. However, as a result of that narrower dimension the evaporator manufacturing depth 2 remains proportionally small.

A minimum manufacturing depth is obtained according to the alternative as specified in Figures 2, 2a and 3rd. In this alternative, intermediate partition 12, which can be form with an integral component 44 as specified in Fig. 2 or as a separate component as specified in the Figures 2a and 3a, work in association with the outer edge 58 of a completely standard partition 60 between channels 26 of each flat pipe 20 acting in a manner similar to a flow. From in this way, separation is achieved in a manner similar to a flow without requiring additional manufacturing depth.

In more detail, the preferred design forms Figures 3, 3a and 4 show the following:

The first and second walls 32 and 34 of the lid of manifold 6 are formed as integral component 44, which, in the represented form, it can be manufactured as a component extruded by impact. The collector lid 6 is made provided with the longitudinal groove 46 in its center, by which it can be pushed from the outside the longitudinal divider 36.

The longitudinal divider 36 is provided with a welding material coating to be welded to the face front 62 of flat pipes 20 and seal the longitudinal groove 46, protruding from the outside of the manifold cover 6 for ensure proper welding.

A cover component is added externally 64 to manifold cover 6 in the area of the transverse grooves 18.

This cover component 64 is placed in first place in manifold lid 6 with so few slots of welding as possible. In addition, if necessary they are introduced existing collars of housing slots 72 in the component of cover 64 for each flat pipe 20, shown internally, in the transverse groove 46 of the manifold 4.

Welding of the cover component 64 is performs, together with other welded joints, in a process oven continued using the method called "one injection".

AlSi 7-12 is used, a non-corrosive fluoride flowing material, such as brazing. The brazing is done at a temperature of 600-610 degrees Celsius.

For a preliminary union of the component of cover 64 before the welding process, the previous one Insert a device in the collector cover 6 first and then, folding both longitudinal edges 68 over a fixing flange 70 in the manifold cover 6, is fixed to is.

For a better assembly, as well as a better welding, from the ends of the flat pipe 23 to the component of cover 64, a direct housing slot 72 is formed in the cover component 64, together with collar 66, in which the end 23 of the flat pipe 20 is introduced. The collar 66 It has the same dimensions of both flat pipe 20 and of the external profile of the collector 4. In this way, a gas-tight welding of the cover component 64 to the cover manifold 6 on the one hand and, on the other, the collar 66 of the component of cover 64 is also connected to the ends of the pipes 20 flat in a gas tight manner.

Due to the division of the pipe, namely spaced along the manifold cap 6 of the pipes flat 20, it is normally 6-15 mm, the slots transverse 18 in the collector cover 6 must be placed only during the cycle mentioned above; in this way, the pressure tightness of the manifold lid 6 looks disturbed only slightly when the grooves are milled transversal 18.

In conjunction with the cover component 64, whose collars 66 are inserted in the transverse grooves 18 in the manifold lid 6, the initial seal of the manifold lid 6 is obtained without the transverse grooves 18.

Not to close both central channels 26 of the flat pipe 20 with the first or second wall 32 or 34 of the cover manifold 6, the transverse groove 18 in the manifold lid 6 it is lowered on the side opposite the front face of the pipe flat 20. Appropriate sealing is achieved between the first and second  compartment 8 and 10 of the manifold cover 6 by means of a longitudinal divider 36, the thickness of which does not depend on the internal overpressure in manifold cover 6, but only of the pressure difference between the first and second compartment 8 or 10, or should be sized, if necessary, from the point of View of its technical production. In the case of a CO2 evaporator 2 with a requirement of pressure resistance of the cover of manifold 6 of at least 250 bars, this means that the thickness of the first or second wall 32 or 34 in any case must be 2.5 mm while the divider welding coating Longitudinal 36 can be made with a thickness of less than 0.2 mm. To achieve a smooth assembly and provide material of sufficient welding as well as being able to respect the tolerances, however, should have a wall thickness of about 1 - 1.5 mm.

In Fig. 3, the longitudinal divider 36 is introduces into the channel 26a in the flat pipe 20, which is not used for continuous flow, with the purpose of creating tightness against the front face 62 of the flat pipe 20.

In Fig. 3a, the longitudinal divider 36 provides tightness directly against a partition intermediate 60 between adjacent channels 26 which provides a longitudinal path in the flat pipe 20, so that the complete blocking of channels 26.

In the design form as specified in Fig. 3a, with the manufacturing depth determined for the flat pipe 20, in order to obtain, as much as possible, a minimum internal diameter for the first or second compartment 8 or 10 of the manifold cover 6 in the direction of the air flow and, next to this, the lowest manufacturing depth in the direction of the air flow as well as the minimum height of the collector cover 6 in the direction of the flat pipe, the collar in the groove of housing 72 in the deck component 64 is performed so thick as the first or second wall 31 or 34 in the areas external

In the area of introduction of collar 66 in the housing slot 72, cross slot 18 in the cover of manifold 6 is recessed on the side opposite the front face 62 of the flat pipe 20 a distance 74, so that, at this point, both external channels 26b of the flat pipe 20 are also not closed by manifold lid 6, but connected to provide flow between the first or second compartment 8 or 10. In the area of the transverse groove 18 in the manifold lid 6, the internal overpressure in evaporator 2 is contained only by middle of cover cover 64. While the component of cover 64 is continuously welded to the long side of the cross slot 18 as specified in Fig. 3 by means of collar 66 mounted internally, in the case of Fig. 3a the cover component 64 must withstand all working pressure of evaporator 2 on both front faces of the transverse groove 18. Due to the small thickness of the transverse groove 18, (2x the thickness of cover component 64 plus pipe thickness flat) of only 3 - 4 mm, however, the thickness of the component of cover increases to 1 - 1.5 mm.

To meet the security features associated with internally mounted vehicle components, in particular working pressures of up to 80 bars in a system of CO2 air conditioning, as well as pressure resistance of up to 250 bars, and a safe process, operations and functions of the manifold lid 6 are divided as follows, such as specified in Figures 3 to 4:

The manifold lid 6 extruded or embedded without welded joints provide a frame that resists pressures operating and provides pressure resistance required As a result of the production process and its form, can at that time produce the security of resistance to pressure required, without being further affected by the process Nocolok welding or variations in the production process of the evaporator

The cover component 64 provides the welding material required. In addition, in the component of cover 64, the minimum tolerances required for welding accommodation slots 72 of less than 0.2 mm, as well as for transverse grooves 18 in the manifold lid 6, can be produce more efficiently at the cost level by pressing, stamping and rolling.

In the construction method set out in Fig. 3a, it is possible to further reduce the size of the component of cover 64 to the inner diameter of the first or second compartment 8 or 10, because the collar 66 in the groove of housing 72 is also inserted into the wall of the cover of collector 6. In this way, it is possible to achieve a reduction additional manufacturing volume as well as wall thickness of the manifold lid 6, while maintaining a resistance at the identical pressure.

The low profile 76 of the transverse groove 18 in the manifold lid 6, which matches a profile of Slot cutter also makes it possible, in the case of Figures 3 and 3a, that both central channels are joined with both sides of the longitudinal divider 36 and, in the case of Fig. 3a, also both external channels 26b with compartments 8 and 10.

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References cited in the description

This list of references cited by the applicant is intended solely to help the reader and not It is part of the European patent document. Although it has been put maximum care in its realization, errors cannot be excluded or omissions and the EPO declines any responsibility in this respect.

Patent documents cited in the description

US 5174373 A [0002] [0009] [0009] [0014] [0014]

EP 0325844 A1 [0004]

EP 0414433 A2 [0005] [0007] [0014]

DE G9111412 U1 [0005] [0011] [0011] [0012] [0014]

Claims (7)

1. An air system evaporator car conditioning (2) presenting a collector that extends longitudinally (4) that defines a first and a second compartment (8, 10), with respectively an input of refrigerant (14) and a refrigerant outlet (16), defining the manifold several slots (18) that extend each in both said compartments (8, 10), further comprising the evaporator several pipes (20) extending from the grooves (18) to a flow return device (28), Characterized by the fact that both compartments (8, 10) of the manifold have the shape of a rounded pipe to provide stability under pressure, the manifold comprises a single piece structure having a longitudinal groove and a dividing element (36) arranged in said groove provided in the manifold and inserted from the outside thereof to separate the aforementioned compartments. 2. The evaporator of claim 1 in the that each pipe is internally divided to provide a step and a return for the aforementioned refrigerant. 3. The evaporator of Claim 1 or 2, in that the above pipes are flat pipes. 4. The evaporator of Claim 1 or 2, in which the longitudinal division element (36) is made of flat material and welded with brazing to the surface of both wall portions (32, 34) between flattened sections with flange shape (40). 5. The evaporator according to any of the preceding claims wherein said slots (18) they are made according to the external profile of the pipes (20) so that maximum allowable tolerances are respected when welding directly in the slot in question (18). 6. The evaporator of any of the preceding claims, wherein both compartments (8, 10)  of the manifold (4) comprise dividing elements that divide each compartment in several sub-compartments (50, 52, 54, 56) displaced with respect to each other from one compartment to another, so that the evaporator refrigerant (2) is driven from one to another side along the manifold (4) between both compartments 7. The evaporator of any of the preceding claims in which both compartments they have a circular cross section.