EP1938034A1

EP1938034A1 - Heat exchanger

Info

Publication number: EP1938034A1
Application number: EP06806023A
Authority: EP
Inventors: Franco Ghiani
Original assignee: Behr GmbH and Co KG
Current assignee: Mahle Behr GmbH and Co KG
Priority date: 2005-10-14
Filing date: 2006-10-04
Publication date: 2008-07-02
Also published as: WO2007042182A1

Abstract

The invention relates to a heat exchanger having tubes (1) through which a medium flows in one direction and between which are arranged guide devices which are connected to the tubes and around which a further medium flows, wherein the tubes (1) are preferably formed from sheet metal (2) and are preferably provided with indentations, wherein at least one tube section (4-7) is provided with a structure, in particular a microstructure. According to the invention, in order to provide a heat exchanger which is cost-effective to produce, the tube section provided with the structure is connected, in the region of a passage, in a cohesive fashion to a base of a collecting tank.

Description

Heat exchanger

The invention relates to a heat exchanger with tubes which are flowed through in one direction by a medium and between which guide means are arranged, which are connected to the tubes and are flowed around by a further medium, wherein the tubes are preferably formed of sheet metal and preferably provided with indentations are.

From the German patent application DE 101 27 084 A1, a heat exchanger with a plurality of flat tubes is known, which are flowed through by a liquid cooling medium. Between the flat tubes are arranged by ambient air acted upon corrugated fins. The flat tubes are provided on at least one of their flat sides with inwardly directed indentations, which are designed as elongated vortex generators with a longitudinal axis. European Patent EP 0 030 072 B1 discloses a heat exchanger with a multiplicity of tubes having a flat cross section, which are formed from metal and allow the passage of a heat transfer medium through the tubes. At least one side wall of each tube has corrugations extending transversely to the longitudinal axis of the tube. The corrugations are uniform and each have a height which is smaller than the wall thickness of the tube. Ribs extend between the tubes and engage and are secured to the top of the corrugations. The object of the invention is to provide a heat exchanger according to the preamble of claim 1, which is inexpensive to produce.

The object is in a heat exchanger with tubes which are flowed through in a direction of a medium and between which guide means are connected, which are connected to the tubes and flowed around by another medium, wherein the tubes are preferably formed of sheet metal and preferably are provided with indentations, wherein at least one pipe section is provided with a structure, in particular a microstructure, achieved in that the provided with the structure pipe section is connected in the region of a passage cohesively with a bottom of a collecting tank. The structure, which is preferably formed on all pipe sections, serves to reinforce the pipe material. This makes it possible to use thinner metal sheets or less material for the production of the tubes than in conventional heat exchangers. In addition, the structure improves the capillary action when connecting the tubes to the louvers. The connection of the tubes with the louvers is preferably carried out by soldering, but can also be done by other cohesive types of connection, such as welding or gluing. The structure is continuous and / or with interrupted depressions.

A preferred embodiment of the heat exchanger is characterized in that the section provided with the structure has a plurality of mutually parallel, elongated depressions and / or elevations. The elongated depressions and elevations significantly increase the stability and strength of the tubes.

A further preferred embodiment of the heat exchanger is characterized in that the section provided with the structure is formed substantially wave-shaped. The structure allows the use of low tube wall thicknesses, especially of very thin metal sheets. A further preferred embodiment of the heat exchanger is characterized in that the section provided with the structure is formed in a zigzag or crenellated manner in cross section. It is also possible to combine different cross-sectional profiles.

A further preferred embodiment of the heat exchanger is characterized in that the elongated recesses and elevations, with respect to the flow direction of the tubes, are arranged inclined at an angle between 0 and 90 degrees. Preferably, the angle is between 30 and 60 degrees. Angles of about 45 degrees have proved to be particularly advantageous.

A further preferred embodiment of the heat exchanger is characterized in that a turbulence insert is arranged in the interior of the tubes. The turbulence insert can be a separate part. The turbulence insert can also be integrated into the tubes.

A further preferred embodiment of the heat exchanger is characterized in that the metal sheet has a thickness of less than 0.5 mm. A thickness of less than 0.3 mm has proved particularly advantageous.

Another preferred embodiment of the heat exchanger is characterized in that the metal sheet is plated with solder. The structure is preferably produced after solder plating, for example by embossing.

A further preferred exemplary embodiment of the heat exchanger is characterized in that the depth or height of the longitudinal depressions and elevations is smaller than the distance between the tubes and the air guiding devices before connecting the tubes to the air guiding devices. The distance is referred to as a soldering, welding or adhesive gap depending on the selected connection. A further preferred exemplary embodiment of the heat exchanger is characterized in that the metal sheet is formed from aluminum, stainless steel, copper or brass. Preferably, the metal sheet consists of at least one alloy with at least one of the aforementioned metals.

Another preferred exemplary embodiment of the heat exchanger is characterized in that a radius is formed on the outside at a folding end. The radius prevents the seam from being damaged when joining the pipe to a bottom of a header tank.

A further preferred embodiment of the heat exchanger is characterized in that the radius at the fold end extends between 0 and 0.1 mm from outside to inside. This size range has proven to be particularly advantageous in the context of the present invention.

A further preferred embodiment of the heat exchanger is characterized in that relatively small through-holes are provided in an inner region of a fold. The through holes serve to optimize the Befluxen.

A further preferred embodiment of the heat exchanger is characterized in that the structure, in particular the microstructure, has depressions and / or elevations which have different shapes and / or extend in one direction or in several different directions. Preferably, the recesses and / or elevations are connected inside and / or outside with a cooling fin or with a plurality of cooling fins.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, various embodiments are described in detail. In this case, the features mentioned in the claims and in the description can each be inventive in their own right or in any combination. Show it: Figure 1 is a perspective view of a tube with a microstructure;

FIG. 2 shows an enlarged detail from FIG. 1 from a different viewing direction;

FIG. 3 shows a further detail from FIG. 1 from a further viewing direction;

Figure 4 is a sectional view of a welded joint;

Figure 5 is a sectional view of a folded joint;

Figure 6 is a further sectional view of a folded joint;

FIG. 7 shows a further perspective illustration of the tube from FIG. 1:

Figure 8 is a section of the tube of Figure 1 in plan view;

FIG. 9 is a side view of a portion of the tube of FIG. 1;

FIG. 10 shows the tube from FIG. 1 in cross section;

Figure 11 is a perspective view of a connection point of the tube of Figure 1;

FIG. 12 shows a section of a tube according to a further exemplary embodiment in plan view;

FIG. 13 shows a section of a tube according to a further exemplary embodiment in plan view;

Figure 14 is a perspective view of a tube according to another embodiment;

Figure 15 is a perspective view of a tube according to another embodiment;

Figure 16 is a perspective view of a tube according to another embodiment;

Figure 17 is a perspective view of a tube according to another embodiment;

FIG. 18 shows a tube according to a further exemplary embodiment in cross section;

Figures perspective views of different Rohrverbin¬

19 to 21 possibilities of training;

Figure 22 is a perspective view of a pipe joint prior to bonding; Figures different pipe cross sections;

23 u. 24

Figure 25 is a similar view as in Figure 22 according to another

Embodiment; Figure 26 further pipe connection options;

Figure 27 is a similar view as in Figure 22 according to another

Embodiment;

FIG. 28 a section from FIG. 27 according to a further exemplary embodiment; Figures similar representations as in Figure 22 according to further embodiments 29 and 30 approximately examples; Figure 31 is a detail of Figure 12; FIG. 32 is a detail of FIG. 13;

FIG. 33 shows further connection possibilities and tube cross sections; FIG. 34 shows a perspective view of a connection point of the pipe from FIG. 1 according to a further exemplary embodiment, and FIG. 35 shows a section of the pipe from FIG. 1 in plan view according to a further exemplary embodiment.

The invention relates to a tube of a heat exchanger, which is provided inside and / or outside with a microstructure. The tube comprises one or more shells that are soldered, welded or glued together at one or more joints. Preferably, the tube has a microstructure on both sides.

According to a variant of the invention, the tubes are formed from a sheet metal material. The structure can be introduced into the raw sheet. However, the structure can also be incorporated into a further processed sheet metal material. Thus, the structure can be embossed, for example, when folding the tubes. At the joints, the sheet material is preferably designed so that a relatively wide contact surface is formed. As a result, smaller solder gaps can be realized. According to a further variant of the invention, the reinforcing structure is formed on extruded tubes. The reinforcing structure allows thinner pipe walls to be realized than with conventional pipes. The associated material savings leads to a significant reduction in weight.

According to a further aspect of the invention, the edge or rim of the tubes is designed so that a wider bearing surface is formed. As a result, smaller solder gaps can be realized in the area of the floor passages. In addition, the guiding, finding, welding and soldering of the formed sheet metal ends is simplified.

In Figure 1, an inventive tube 1 is shown in perspective. The tube 1 is formed from a piece of sheet metal 2 and has a substantially rectangular cross-section. The metal sheet 2 has two rectangular main surfaces 4 and 5, which are interconnected by two likewise rectangular side surfaces 6, 7. Furthermore, the tube 1 has two open ends 8, 9. The surfaces 4 to 7 of the tube 1, which are also referred to as sections, are provided according to an essential aspect of the invention with a continuous structure.

In Figure 2, a detail of Figure 1 is shown enlarged. In the enlarged illustration, it can be seen that the side surface 7 has a substantially crenellated cross-section 11. The crenellated cross section 11 causes the side surface 7 has a plurality of elongated, cuboidal elevations 14, 16. Between two elongated elevations 14, 16, an elongated recess 15, 17 is arranged in each case. The elevations 14, 16 and depressions 15, 17 extend diagonally in the side surface 7. The further surfaces of the tube 1 are formed in the same way as the surface 7. A planar section 18, 19 is formed between the individual surfaces. By the flat portions 18, 19, the surfaces or sections 4 to 7 are integrally connected.

In Figure 3 it can be seen that the side surface 6 has a longitudinally extending connecting line 22 at which two ends of the metal sheet 2 are connected to each other. The metal sheet 2 is a strip-shaped strip material. In Figure 4 it is indicated that the two ends of the metal sheet can be welded together.

In FIG. 5, it is indicated that the two ends of the metal sheet can be connected to one another at the connecting line 22 by a folded connection.

In Figure 6, another embodiment of a rabbet joint is shown in section. Preferably, the two ends of the metal sheet are connected by crimping cohesively after folding.

In Figure 7 is indicated by arrows 31, 32, that the tube 1 is flowed through in the installed state of a medium. In addition, one sees in FIG. 7 that the main surface 4 of the metal sheet 2 is also provided with a continuous structure of elongated depressions and elevations.

In Figure 8, the main surface 4 is shown in plan view. In plan view, it can be seen that the major surface 4 has a plurality of elongate ridges 34, 36 and recesses 35, 37. The elongate elevations and depressions extend parallel to each other at an angle of 45 degrees to the direction of pipe flow, which is indicated by the arrows 31 and 32.

In FIG. 9 it can be seen that the side surface 6 is provided with the same structure as the main surface (4 in FIG. 8). The side surface 6 has a plurality of mutually parallel, elongated elevations 41, 43 and depressions 42, 44. The elevations and depressions are diagonal.

In Figure 10, the tube 1 is shown in cross section. The cross section has essentially the shape of a rectangle. Inside the tube 1 may be arranged a turbulence insert. The turbulence insert can be made in one piece with the metal sheet 2. But it can also be arranged in the tube 1, a separate turbulence insert. In FIG. 11 it is shown that the two ends of the metal sheet 2 can also be connected by connecting straps 47, 48 which abut one another in an overlapping region. The connecting straps 47, 48 can be connected to one another in a form-fitting manner, for example by folding, and / or by material engagement, for example by soldering or welding.

FIG. 12 shows a main surface 4 of a tube according to the invention in a plan view according to a further exemplary embodiment. The main surface 4 has three longitudinal sections 51 to 53 with different structures. The longitudinal section 51 has diagonally extending, elongated depressions and elevations. The longitudinal section 53 also has diagonally extending, elongated depressions and elevations. However, the elongated elevations and depressions are arranged in the longitudinal section 53 at an angle of 90 degrees to the elevations and depressions of the longitudinal section 51. The longitudinal section 52 is arranged between the two longitudinal sections 51 and 53. In the longitudinal section 52, a herringbone pattern of elongate ridges and valleys is formed.

In FIG. 13, the longitudinal sections 51 to 53 from FIG. 12 are shown enlarged. In the enlarged illustration, it can be seen that the elongate elevations and depressions in the various longitudinal sections 51 to 53 are integrally connected to one another.

FIG. 14 shows a perspective view of an exemplary embodiment of a pipe in which partitions 55 to 58 originate from the main surfaces 4, 5 of the pipe. The partition walls 55 to 58 are arranged alternately parallel to each other. The partitions 55 and 56 extend in a vertical direction from the main surface 5 to the main surface 4. The partitions 57, 58 extend in a vertical direction from the main surface 4 to the main surface 5. The partition 57 is in the middle between the two Partitions 55 and 56 arranged. The partition wall 56 is located midway between the partitions 57 and 58. By the partition walls 55 to 58, the interior of the tube is divided into a plurality of individual channels. In Figure 15, another embodiment of a tube is shown in perspective. In this embodiment, the main surfaces 4, 5 each have a castellated cross-section. The main surface 5 is provided with a multiplicity of elongate elevations 61, 63 and depressions 62, 64. The elevations and depressions extend in the longitudinal direction of the tube. The main surface 4 is integrally connected to the main surface 5 through the side surface 7. The main surface 4 has the same crenellated cross-sectional structure as the main surface 5. A plurality of elongate ridges 65, 66 and recesses 67, 68 extend longitudinally of the tube. In this case, the elevations 61, 65 and 63, 67 of the main surfaces 5 and 4 are respectively arranged opposite one another. The recesses 62, 64 and 66, 68 of the main surfaces 5 and 4 abut each other. By this arrangement, a plurality of individual channels is formed in the interior of the tube, which extend in the longitudinal direction.

In Figure 16, an embodiment is shown in perspective, in which emanate from the main surfaces 4, 5 partitions 71 to 74. The partition walls 71 to 74 are arranged perpendicular to the main surfaces 4, 5. With their ends, the partitions 71 and 73 and 72 and 74 abut each other. Thereby, a plurality of longitudinally extending channels is formed in the interior of the tube.

FIG. 17 shows a further exemplary embodiment of a tube, which is similar to the embodiment shown in FIG. To avoid repetition, reference is made to the preceding description of FIG. In contrast to the exemplary embodiment illustrated in FIG. 15, in the exemplary embodiment illustrated in FIG. 17, longitudinal webs 76, 77 and 78, 79, which bear against one another, are formed at the lateral ends of the main surfaces. Preferably, the adjacent webs are connected to one another in a material-locking manner.

FIG. 18 shows a tube 81 with a round cross section. The tube 81 is formed from a sheet metal strip 82 and equipped with a microstructure according to the invention. The metal sheet 82 is provided with a crenellated cross section having a plurality of elevations 84, 86 and recesses 85, 87 which extend obliquely to the longitudinal axis of the tube 81.

FIG. 19 shows in perspective that two rims 91 and 92 can project outwards at a connection point 90 of a pipe.

In FIG. 20, it is indicated that two ribs can protrude inwards at a connection point 93 of a pipe.

In FIG. 21, it is indicated that at one connection point 96 one board 97 can protrude inwards and another board 98 can project outwards. The pipe connection possibilities illustrated in FIGS. 19 to 21 are preferably designed as welded or soldered connections. The pipe ends to be connected abut each other with the ribs.

In Figure 22, a junction of a pipe is shown in perspective before connecting the shelves. At 101 and 102 it is indicated that the pipe cross-section can be provided with radii at different locations.

FIG. 23 shows various tube cross sections 104 to 109. The tube cross section 104 has two radii 111 and 112, which are connected by straight lines. The tube cross-section 105 has substantially the shape of a rectangle with rounded corners, as indicated at 114. The tube cross section 106 is similar to the tube cross section 105. However, the tube cross section 106 has different radii 115 and 116 in the corner regions. The tube cross section 107 is oval. The tube cross section 108 is round. The tube cross-section 109 is similar to the tube cross-section 104. The microstructure of the tubes can be designed to be parallel around the circumference. The microstructure may also leak at the corner radii. The microstructure may be provided over the entire surface or only in certain areas.

FIG. 24 shows further tube cross sections which are partially equipped with a turbulence insert or a support rib. In Figure 25, a tube with two shelves 121, 122 is shown in perspective before connecting. The two shelves 121, 122 each have an angular profile and engage in a form-fitting manner. Various dimensions of the tube are designated a, b, F and G. The offset between the ribs 121 and 122 corresponds optimally / maximally to the material thickness plus G or the material thickness plus F. The dimension a is preferably the same as the dimension b. If the dimension a is zero, then it must be ensured that the dimension b is not greater than the maximum soldering gap. If the measure b is zero, then it must be ensured that the dimension a is smaller than the maximum soldering gap.

In Figure 26 different board connection options are shown, which are preferably produced by welding.

In Figure 27, a tube with two rims 124, 125 is shown in perspective, the form-fitting interlock. Various dimensions of the tube are denoted by d _in n _e , e, F, G, T1, T2 and R (b). If F is zero then G should be the size of the maximum solder gap. If G is zero then F should be the size of the maximum solder gap. Otherwise, care should be taken that F equals G. T2 is preferably twice the size of T1. T2 can also be just as large or smaller or greater than T1, d (inside or outside) should correspond to the radius R (b). For d or e the following combinations are possible: d or e = 1 x R (b); d = 2 x R (b) +0 - 1, 0; d = 2 x R (b) + 0 - 1, 5; d = 2 x R (b) + 0 - 2.0; d = 2 x R (b) + 0 - 2.5; d = 2 x R (b) + 0 - 3.0; d = 2 x R (b) + 0 - 3.5; d = 2 x R (b) + 0 - 4.0; d = 2 x R (b) + 0 - 4.5; d = 2 x R (b) + 0 - 5.0; d = 2 x R (b) + 0 - 5.5; D = 2 x R (b) +0 - 6.0; d = 2 x R (b) + 0 - 6.5; d = 2 x R (b) + 0 - 7.0; d = 2 x R (b) + 0 - 7.5; d = 2 x R (b) + 0 - 8.0; d = 2 x R (b) + 0 - 8.5; d = 2 x R (b) + 0 - 9.0; d = 2 x R (b) + 0 - 9.5; d = 2 x R (b) + 0 - 10.0. If d is less than or equal to the maximum soldering gap, then F or G may be greater than the maximum soldering gap. If G or F is smaller than the maximum soldering gap, then d (inside / outside) may be larger than the maximum soldering gap. Different divisions can be combined. The microstructure channels can run parallel or at an angle to each other. The letter S denotes the structure depth. In FIG. 28 it is indicated that the angle W is preferably between 0 and 45 degrees.

FIG. 29 shows a similar connection point as in FIG. In FIG. 29 it can be seen that the structure can have a plurality of radii R (a), R (b), R (c) and / or R (e). The material thickness can be reduced by up to 70 percent in the radius transition area. The measure e results from the sum of d with the material thickness.

In Fig. 30, a possible offset between the shelves 124 and 125 is indicated by x. The offset should be less than the material thickness or less than the sum of the material thickness and the texture depth.

FIG. 31 shows a section of FIG. 12 in which different angles are designated α1 and β1. The angles α1 and β1 are between 0 and 90 degrees.

FIG. 32 shows a section from FIG. 13. 1 indicates that two structural lines converge at an angle in each case. At 2 it is indicated that the structure lines can also be connected by radii.

FIG. 33 shows further on-board connection possibilities with or without turbulence insert in cross-section. The turbulence insert can be provided with or without structure. A gap s results in all versions after soldering. The illustrated on-board connections can also be used for tubes with a round or oval cross-section.

In FIG. 34 it is shown that the outer connecting strap 48, which is also referred to as a folding end, can be provided with a radius R at its end. The radius R extends at a distance A from outside to inside. The distance A is between 0 and 0.1 mm. In an inner region 150 of a fold relatively small through holes may be provided. In Figure 35, the main surface 4 is shown in plan view. In various areas 161, 162, 163, 164, 165 and 166 it is indicated that the most varied forms of elevations and / or depressions can be combined with one another. Mosaic, linear, round and round, oval, round, three or more corners as well as combinations of several geometries are possible. The ridges or depressions may be in the form of corrugations, pyramids, cylinders, a torus or a cone.

Claims

Patent claims

1. Heat exchanger with tubes (1; 81), which are flowed through in one direction by a medium and between which guide devices are arranged, which are connected to the tubes and are flowed around by a further medium, wherein the tubes (1, 81) preferably formed from sheet metal (2; 82) and preferably provided with impressions, wherein at least one pipe section (4-7) is provided with a structure, in particular a microstructure, characterized in that the pipe section provided with the structure is in the region of Passage is materially connected to a bottom of a collecting tank.

2. Heat exchanger according to claim 1, characterized in that the provided with the structure portion (4-7) a plurality of mutually parallel, elongated recesses and / or elevations (14- 17; 34-37; 41-44; 61-68; 84-87).

3. Heat exchanger according to one of the preceding claims, characterized in that the provided with the structure portion (4-7) is formed substantially wave-shaped.

4. Heat exchanger according to one of the preceding claims, characterized in that the provided with the structure portion (4-7) is formed in a zigzag cross-section.

5. Heat exchanger according to one of the preceding claims, characterized in that the provided with the structure portion (4-7) is crenellated in cross section.

6. Heat exchanger according to one of claims 2 to 5, characterized in that the elongated recesses and elevations (14-17, 34-37, 41-44, 61-68, 84-87), relative to the flow direction of the tubes, in an angle between 0 and 90 degrees are arranged inclined.

7. Heat exchanger according to one of the preceding claims, characterized in that a turbulence insert is arranged in the interior of the tubes (1; 81).

8. Heat exchanger according to one of the preceding claims, characterized in that the metal sheet (2, 82) has a thickness of less than 0.5 mm, in particular less than 0.3 mm.

9. Heat exchanger according to one of the preceding claims, characterized in that the metal sheet (2; 82) is plated with solder.

10. Heat exchanger according to one of claims 2 to 9, characterized in that the depth or height of the elongated recesses and elevations (14-17; 34-37; 41-44; 61-68; 84-87) smaller than that Distance between the pipes (1, 81) and the louvers before connecting the pipes with the louvers is.

11. Heat exchanger according to one of the preceding claims, characterized in that the metal sheet (2; 82) is made of aluminum,

Stainless steel, copper or brass is formed.

12. Heat exchanger according to one of the preceding claims, characterized in that at a fold end (48) outside a Radi- us R is formed.

13. Heat exchanger according to claim 12, characterized in that the radius R at the folding end (48) extends between O and 0.1 mm from outside to inside.

14. Heat exchanger according to one of the preceding claims, characterized in that in an inner region (15) of a fold relatively small through holes are provided.

15. Heat exchanger according to one of the preceding claims, character- ized in that the structure (161-166), in particular the

Microstructure, depressions and / or elevations having different shapes and / or extending in one direction or in several different directions.