EP1558887A2

EP1558887A2 - Multiple-pass heat exchanger, in particular for motor vehicle

Info

Publication number: EP1558887A2
Application number: EP03786005A
Authority: EP
Inventors: Sylvain Moreau
Original assignee: Valeo Climatisation SA
Current assignee: Valeo Systemes Thermiques SAS
Priority date: 2002-11-08
Filing date: 2003-11-10
Publication date: 2005-08-03
Anticipated expiration: 2023-11-10
Also published as: EP1558887B1; WO2004044513A2; FR2847031A1; AU2003295013A8; WO2004044513A3; FR2847031B1; ES2309381T3; ATE400783T1; DE60322090D1; JP2006505759A; AU2003295013A1

Abstract

The heat exchanger has a collector (18) receiving the ends of multiple tubes (12,14). A collector box (20) covers the collector, and has a longitudinal wall (40) in contact with the collector defining first (50) and second (52) compartments into which the tubes open. The collector has a hollow region (56) facing the wall (40) to allow communication between the first and second compartments.

Description

Multiple pass heat exchanger, in particular for vehicle, automobile

The invention relates to heat exchangers, in particular for motor vehicles.

It relates more particularly to a heat exchanger of the type comprising a manifold in which are 'received ^the' ends of at least one row of tubes and a collecting box which covers the manifold and which has a longitudinal partition having a free edge is in contact with the collector to delimit a first compartment and a second compartment into which at least part of the tubes open respectively.

In a heat exchanger of this type, the row or rows of tubes together form a bundle of tubes with which heat exchange surfaces are usually associated, such as, for example, corrugated spacers.

Most often, the heat exchanger includes a first manifold / manifold assembly at one end of the tube bundle and a second manifold / manifold assembly at a second end of the tube bundle.

Such a heat exchanger can comprise, for example, a first row of tubes and a second row of tubes which open respectively into the first compartment and the second compartment.

The fluid which traverses the tubes of the bundle usually circulates in several passes in the first row of tubes, generally with counter-current circulations, to then gain the second row of tubes where it also usually circulates in several passes and against the current . It is therefore necessary to be able to pass the fluid from a longitudinal compartment to an adjacent longitudinal compartment and thus pass from one ply to another.

Alternatively, the heat exchanger may include only one; row of ;;, tubes, which _. each delimit a ^" plurality of fluid circulation channels. In this case, a first part and a second part of the channels of each tube can lead respectively into the first compartment and into the second compartment.

In this case, there is also the problem of the passage of the fluid from one longitudinal compartment to another longitudinal compartment.

In known exchangers, this passage is usually carried out through one or more openings arranged in the longitudinal partition, as taught for example by the publication US 2002/0066553.

Thus, the passage from one longitudinal compartment to another longitudinal compartment which corresponds to the "ply change" function takes place through the longitudinal partition through openings arranged through it. It will be understood that the term "sheet" can denote both a row of tubes (usually in a heat exchanger with several rows of tubes) and part of the channels of the tubes of a row (usually in the case of an exchanger heat from a single row of tubes).

This known solution therefore requires an additional operation for the realization of the opening or openings considered.

The object of the invention is in particular to overcome this downside.

It aims to propose another solution, much simpler, to allow the passage of fluid from one longitudinal compartment to another, without the need to cross the longitudinal partition.

According to the invention, this solution applies to ^* different types of heat exchangers, whether they are exchangers with a single row of tubes, with two rows of tubes, or with more than two rows of tubes.

The invention provides for this purpose a heat exchanger of the type defined above, in which the collector comprises at least one deformation to form at least one communication passage between the first compartment and the second compartment.

The deformation of the collector can take different forms. However, preferably, it is constituted by at least one hollow region which is distant from the free edge of the longitudinal partition.

Thanks to this characteristic, it is possible to use a solid longitudinal partition, which avoids having to provide special tools for perforating said partition.

Thus, thanks to a particular arrangement of the collector, a communication passage is formed which extends between this hollow region of the collector and the partition, which allows the fluid to pass under the longitudinal partition, without passing through it.

This solution is particularly advantageous because it allows this communication passage to be carried out by an arrangement of the collector which can be carried out in a simple manner. Advantageously, at least one communication passage is provided in an end region of the compartments.

According to another characteristic of the invention, at least one communication passage delimits a calibrated passage section.

This _{"calibration.} Allows" minimize losses, de_ ^'.charge, the fluid passing through this section. In the case where the communication passage is carried out by several openings, the calibration of these also makes it possible to control the flow rate passing through each opening. This makes it possible to balance the flow rates passing through the different tubes of the exchanger.

In a first general embodiment of the invention, the collector and the manifold are formed from two separate parts.

In this case, the collector is preferably made in the form of a metal plate in which the hollow region is formed by stamping.

It is advantageous, in this case, for the manifold to be a shape with constant section integrating the longitudinal partition. This shape can be obtained by extrusion or stamping of a material, preferably metallic, or by molding a material, preferably a plastic.

In a second general embodiment of the invention, the manifold and the manifold are formed in one piece. In this case, it is advantageous for the collector. and the manifold are formed from a metal sheet having a central part forming the collector, including its hollow region, and two marginal parts folded in the direction of the central part to help delimit the compartments and to form jointly the longitudinal partition.

In this second embodiment of the invention, the hollow region of the collector is advantageously formed by stamping the central part of the metal sheet.

The invention can be applied, for example, to a heat exchanger comprising a first. row of tubes and ^" a second row of tubes which open into the first compartment and into the second compartment respectively.

It can also be applied, for example, to a heat exchanger comprising a single row of tubes each delimiting a plurality of fluid circulation channels, a first part and a second part of the channels of each tube opening respectively into the first compartment and in the second compartment.

The invention applies in particular to a heat exchanger in which the tubes are flat tubes, the exchanger further comprising corrugated spacers in contact with the tubes.

The heat exchanger of the invention is advantageously produced in the form of an evaporator for a motor vehicle air conditioning circuit. Of course, this application is not limiting, and the heat exchanger can also be used to constitute an air conditioning condenser or a radiator for cooling a motor vehicle engine, or even a heating radiator for the passenger compartment of a motor vehicle.

In the description which follows, given solely by way of example, reference is made to the appended drawings, in which:

- Figure 1 is a perspective and partially exploded view of a heat exchanger with two rows of tubes according to the invention; - Figure 2 is a detail on an enlarged scale of Figure 1;

- Figure 3 is a cross-sectional view of a manifold / manifold assembly according to another embodiment of the invention;

- Figure 4 is a partial exploded perspective view of a heat exchanger with a single row of tubes according to the invention; and

FIG. 5 is an end view, on an enlarged scale, of the heat exchanger of FIG. 4.

The heat exchanger shown in FIG. 1 comprises a bundle 10 formed of a first row of tubes 12 which constitutes a first ply (here directed towards the front) and a second row of tubes 14 which constitutes a second ply (here rearward). These flat tubes are arranged parallel to each other, each tube of a first row being aligned with a corresponding tube of the second row. Corrugated spacers 16 forming heat exchange surfaces are in mechanical and thermal contact with the respective tubes of the two rows. In the example, the tubes 12 and 14 are obtained by extrusion of a metallic material, advantageously based on aluminum, and they each comprise a multiplicity of internal channels, which are best seen in the detail of FIG. 2 , for the circulation of a fluid. This exchanger can in particular be produced in the form of an evaporator for an air conditioning circuit, the fluid passing through the tubes then being a cooling fluid.

The ends of the tubes 12 and 14 are received on the one hand in a collector 18 (here in the upper part) capped by a manifold 20 and on the other hand in a collector 22 ⁽ here in the lower part) capped by a box collector 24. The collector 18 is a metal plate of generally rectangular shape comprising a generally flat bottom 26 which is folded at its two ends to form two raised edges 28 and 30.

The bottom 26 of the manifold 18 is pierced with apertures of suitable shape which respectively receive the ends of the tubes ;; 12 and 14. The bottom _. '26' of the manifold ;;, exceeds du_faisçeau 10 (on the left side in Figure 1) to form an extension in which are arranged an inlet orifice 32 and an outlet orifice 34 for the fluid flowing in the exchanger. These two orifices 32 and 34 are spaced in the transverse direction, the orifice 32 being situated on the side of the row of tubes 12 and the orifice 34 on the side of the row of tubes 14.

The manifold 20, which forms a cover, here consists of an extruded profile, advantageously of metallic material, for example based on aluminum. This profile is shaped and has a constant section which has the shape of a double U formed by a first U-shaped wall 36 located on the side of the tubes 12 and a second U-shaped wall 38 located on the side of the tubes 14. The junction between the two walls forms a partition 40 having a free edge 42 capable of coming into tight contact with the bottom 26 of the manifold in a region between the row of tubes 12 and the row of tubes 14. The contact zone is designated by the reference 44.

When the manifold 20 is assembled on the manifold 18, the assembly delimits two longitudinal chambers on either side of the partition 40, a first chamber communicating with the tubes 12 and a second chamber communicating with the tubes 14. These two longitudinal chambers are themselves divided lengthwise by a transverse partition .46. In this way, the two longitudinal chambers are divided into four compartments: a compartment 48 in which a part PI of the tubes 12 opens (here consisting of fifteen tubes), a compartment 50 into which a second part P2 of the tubes 12 opens (here composed of fifteen tubes 12). Correspondingly, the wall 38 delimits, together with the transverse partition 46, a compartment 52 into which opens a part of the tubes 14 (here fifteen in number) and a compartment 54 into which opens a '.autre-;' part of the _.. tubes..14 /;. (here ^" number ... of.-. fifteen).

The manifold 24 covering the manifold 22 is analogous to the manifold 20, which allows the same type of profile to be used. This manifold thus delimits two longitudinal chambers which, unlike the upper manifold 20, are not divided by a transverse partition.

In the exchanger of Figure 1, the fluid enters the compartment 48 through the inlet port 32, circulates in the tubes 12 of the PI part to reach a first longitudinal chamber of the manifold 24 and reach the tubes 12 of part P2. From there, the fluid reaches the compartment 50. It then reaches the compartment 52 in the transverse direction, by particular arrangements which will be described later. The fluid circulates in a part of the tubes 14 to gain the second longitudinal chamber of the manifold 24 and then circulate in another part of the tubes 14 to gain the compartment 54. Finally, the fluid leaves the exchanger through the outlet orifice 34.

As already indicated, to allow communication from compartment 50 to compartment 52, arrangements were previously made, that is to say openings in the partition 40.

The invention makes it possible to avoid this solution thanks to a particular arrangement of the bottom 26 of the collector. As we best seen in the detail of Figure 2, the bottom 26 of the collector comprises a deformed region, here a hollow 56 which has the shape of a bowl of substantially rectangular outline and which is located on the side of the raised edge 30. In this hollow region open, in the example, seven tubes 12 and seven tubes 14. as a result, in this region, the free edge 42 of the partition is no longer in contact with the "bottom of _{_26.} collector, this ^" which ^" thus delimits a communication passage 58 between the compartments 50 and 52 as illustrated by the arrows F in FIG. 2. The communication passage 58 offers a calibrated passage section determined inter alia by the distance which separates the free edge 42 of the partition 40 and the hollow region 56.

The exchanger of Figures 1 and 2 is formed only from metallic components capable of being brazed in a single operation in a suitable brazing furnace. For this, the metal components are coated with a solder plating, as is well known in the art.

Alternatively, the manifold 20 could be crimped onto the manifold 18 by suitable means, for example by tabs from the manifold and _. coming to bear on the edges of the manifold. The latter could, alternatively, be made of plastic.

It is also conceivable to produce the manifold 18 / manifold box 20 assembly in one piece. For this, as shown in FIG. 3, it is possible to use a metal sheet 60 having a central part 62 intended to form the collector and two marginal parts 64 intended to be folded in the direction of the central part. These two marginal parts have respective free edges 66 which come to bear against the central part 62 to jointly form a central partition 40. The central part 62 is deformed, preferably by stamping, to form the hollow region 56 and thus the communication passage 58 making the two compartments communicate adjacent.

To make a collector / collector box assembly in this way, one starts from a flat metal sheet of generally rectangular shape. We first start by forming in the central part the openings for the passage of the tubes then we stamp this central part, over part of its length, '" _{.. to} form _/ ; the ~ region ^" hollow..56 .. In a subsequent step, the two marginal parts 64 are folded in the direction of the central part to delimit the compartments and jointly form the longitudinal partition.

The heat exchanger shown in Figures 4 and 5 s 'pparente to that of Figures 1 and 2 except that it comprises here ^a' single row of tubes 70, here of the flat tubes between which are disposed corrugated spacers 12.

The tubes 70 are called "multi-channel tubes" because they each define a plurality of fluid circulation channels 72 which extend parallel to one another. These tubes are produced by extrusion. The channels 72 of each tube 70 are divided into two parts NI and N2 which, in the example, include the same number of channels. These two parts NI and N2 are separated by an interval 74, which is located substantially in the middle of the tube, and which has no channels.

The manifold 18 here receives a manifold 20 similar to that of FIGS. 1 and 2. When the latter is applied against the manifold, the free edge 42 of the partition comes to rest on the respective intervals 74 of the tubes 70 which open into the region in hollow 56. In this way, the first parts NI of the tubes 70 and the second parts N2 of the tubes 70 respectively constitute two plies which open respectively into compartments 50 and 52 similar to those described above with reference to Figures 1 and 2. The fluid can thus pass from the first layer to the second layer or vice versa via the hollow region 56.

It will be understood that the invention is susceptible of numerous variant embodiments. Each manifold / manifold assembly may be formed of two parts or of a single part as mentioned above. It is also possible to provide 1 exchanger _. comprises more than two rows _, of tubes and that several communication passages are provided in the same manifold / manifold assembly.

The invention finds particular application to heat exchangers for motor vehicles. As such, one of the preferred applications is that of an evaporator for an air conditioning circuit. However, other exchangers can be produced using this technique.

Claims

claims

1. Heat exchanger of the type comprising a collector (18) in which the ends of at least one row of tubes (12, 14; 70) are received, as well as a manifold (20) which covers the collector and which presents a. longitudinal partition ^" (40), a free edge (42) of which is in contact with the manifold to delimit a first compartment (50) and a second compartment (52) into which at least part of the tubes (12, 14; 70),

characterized in that the manifold (18) has at least one deformation (56) to form at least one communication passage (56) between the first compartment (50) and the second compartment (52).

2. Heat exchanger according to claim 1, characterized in that the longitudinal partition (40) is full.

3. Heat exchanger according to one of claims 1 and 2, characterized in that the deformation (56) of the collector (18) consists of at least one hollow region (56) which is distant from the free edge (42) of the longitudinal partition (40).

4. Heat exchanger according to one of claims 1 to 3, characterized in that at least one communication passage (56) is provided in an end region of the compartments (50, 52).

5. Heat exchanger according to one of claims 1 to 4, characterized in that a communication passage (56) at least delimits a calibrated passage section (58).

6. Heat exchanger according to one of claims 1 to 5, characterized in that the manifold (18) and the manifold (20) are formed from two separate parts.

7. Heat exchanger according to claim 6, characterized in that the collector (18) is a metal plate in which the hollow region (56) is formed by stamping.

8. Heat exchanger according to one of claims 6 and 7, characterized in that the manifold (20) is a shape with constant section. integrating the longitudinal partition (40).

9. Heat exchanger according to claim 8, characterized in that the manifold (20) is formed by extrusion of a material, preferably metallic.

10. Heat exchanger according to claim 8, characterized in that the manifold (20) is formed by stamping a material, preferably metallic.

11. Heat exchanger according to claim 8, characterized in that the manifold (20) is formed by molding a material, preferably a plastic.

12. Heat exchanger according to one of claims 1 to 5, characterized in that the manifold (18) and the manifold (20) are formed in one piece.

13. Heat exchanger ^' according to claim 12, characterized in that the collector (18) and the manifold (20) are formed from a metal sheet (60) having a central part (62) forming the collector, including its hollow region (56), and two marginal parts (64) folded in the direction of the central part to help delimit the compartments (50, 52) and jointly form the longitudinal partition (40).

14. Heat exchanger according to claim 13, characterized in that the hollow region (56) of the collector is formed by stamping the central part (62) of the metal sheet (60).

15. Heat exchanger according to one of claims 1 to 14 / _. / characterized ^~ in 'this. that it comprises ^" a first ^" row of tubes (12) and a second row of tubes (14) which open respectively into the first compartment (50) and into the second compartment (52).

16. Heat exchanger according to one of claims 1 to 14, characterized in that it comprises a single row of tubes (70) each delimiting a plurality of channels (72) for circulation of fluid, and in that a first part (NI) and a second part (N2) of the channels of each tube open respectively into the first compartment (50) and into the second compartment (52).

17. Heat exchanger according to one of claims 1 to

16, characterized in that the tubes (12, 14; 70) are flat tubes and in that it further comprises corrugated spacers (16) in contact with the tubes.

18. Heat exchanger according to one of claims 1 to

17, characterized in that it constitutes an evaporator for an air conditioning circuit, in particular of a motor vehicle.