WO2008151680A1

WO2008151680A1 - Heat exchanger

Info

Publication number: WO2008151680A1
Application number: PCT/EP2008/001951
Authority: WO
Inventors: Helmut Roll
Original assignee: Modine Manufacturing Company
Priority date: 2007-06-15
Filing date: 2008-03-12
Publication date: 2008-12-18
Also published as: EP2167895A1; EP2167895B1; DE102007027706A1

Abstract

The invention relates to a heat exchanger consisting of flat tubes (1) having wide and narrow sides, and of ribs (2) which form a block, and of at least one tube bottom (3)/collection box (4) with at least two unformed longitudinal edges (30, 40) opposite one another, characterized in that projections (41) are disposed at intervals at edges (40) of the collection box (4), in that the narrow sides of the flat tubes (1) lie against the longitudinal edges (30) of the tube bottom (3) or of the collection box and are connected. The projections (41) engage the longitudinal edges (30) and are located between the flat tubes (1). The invention also relates to a production method. Among other things, the invention leads to heat exchangers which are quite resistant to temperature change loads and which can be produced relatively inexpensively.

Description

heat exchangers

The invention relates to a heat exchanger, comprising flat and narrow sides having flat tubes and ribs which form a block and having the further features listed in the preamble of claims 1 and 2, respectively. The heat exchanger described in the preamble is known, for example, from DE 198 19 247 A1 and also from WO 2006/133748 A1. The projections provided in the first-mentioned reference correspond to openings in the tubesheets. As a result, a provisional cohesion of the items is provided before performing the soldering process. The effort for soldering auxiliary device can therefore be reduced. A certain disadvantage of this heat exchanger is that there is still a significant overhang of the tubesheet over the ribbed flat tube block which could be considered unnecessary space requirements. Furthermore, the ratio of the cross-sectional area occupied by the flat tubes is not optimal in comparison to the entire cross-sectional area of the heat exchanger or its tube plates, so that improvements are possible with regard to efficient space utilization of the heat exchanger. In addition, this heat exchanger could be regarded as insufficiently equipped for thermal cycling. In the second reference mentioned also projections have been provided, which are, however, inserted into the ends of the flat tubes, in each case in the region of the narrow sides thereof. It has already been proven that this heat exchanger has considerable advantages over other solutions. However, it is desirable to have suitable back-up solutions available, for example in the event that the heat exchanger known from this reference should not be able to cope with the most extreme requirements with regard to the thermal cycling. Usually occur at extreme loads damage, such as fractures or the like, in the connecting region of the flat tubes with the tube sheets and that usually at or near the narrow sides of the flat tubes. The known heat exchanger could be considered as endangered in the mentioned range, for example, when it is intended to drastically reduce the wall thickness of the flat tubes.

The object of the invention is to provide heat exchangers available which in part have an even higher resistance to Expect thermal cycling or at least sufficient resistance, with relatively good thermal performance. As a side effect, a production-friendly, in particular a flexible design can be assumed. According to the preferred teaching of the invention, the narrow sides of the flat tubes at the longitudinal edges of the tube sheet abutment and because the projections engage in the longitudinal edges, the projections sit between the flat tubes and border the narrow sides, the resistance to thermal cycling was comparatively further improved, because the particularly vulnerable area of the narrow sides of the flat tubes was significantly strengthened, and amplified without additional, the cost and weight-increasing, reinforcing parts must be used, as it has been proposed several times in other publications. On the one hand lie according to the invention, the narrow sides of the flat tubes namely at the longitudinal edges and are connected thereto and on the other hand, each Tlachrohrende is bordered or supported in the narrow sides of two projections, so that the improvement of the resistance is traceable.

Although provided in accordance with the preferred teaching part feature, according to which the projections sit between the flat tubes, may indeed have been known in the prior art, but are the prior art, the projections in corresponding openings (slots) in the tube sheets and provide Therefore, according to the proposal, on the other hand support the projections according to claim 3 at the bottom of the deformed longitudinal edges or they are trapped therein. Openings in the tube sheets are not provided, which is why the mentioned risk is eliminated by the invention.

Since, according to the invention - as already mentioned - the narrow sides of the flat tubes lie on the longitudinal edge of the tubesheets inside, the supernatant of the tubesheet over the block of flat tubes and ribs extremely minimal, which is why the initially mentioned ratio of the occupied by the flat tubes cross sections in Compared to the entire cross section of the heat exchanger or to its

Tube sheets was significantly improved.

A second solution according to the invention provides that the narrow sides of the

Flat tubes in the edges of the tube sheet / collecting tank either embedded and connected to the edges or there just rest and are connected without being embedded, the tube sheet and the collection box are either one piece or at least formed in two pieces. For the purpose of

Embedding are spaced grooves or slots.

Projections, as described in the first solution, are not necessary here. Also, this proposal provides a heat exchanger with sufficient resistance to thermal cycling, and it is feasible with competitive cost.

Further features are contained in numerous dependent claims, which are to be regarded as detailed here. In addition, the features and their far-reaching benefits result from the following

DESCRIPTION OF EMBODIMENTS TO BE CARRIED OUT WITH THE ACCOMPANYING DRAWINGS.

The figures show the following:

Fig. 1 shows a perspective, partially exploded view of a portion of a Kühlflüsskühlers invention. Fig. 2 shows the

Detail F from FIG. 1.

FIG. 3 shows the part according to FIG. 1 in the assembled state and FIG. 4 shows the detail A from FIG. 3. FIG. 5 shows the detail according to FIG. 2 from a different perspective. FIG. 6 shows a representation similar to FIG. 1 but using the example of FIG

Intercooler and Fig. 7 shows the detail D of FIG. 6th

FIG. 8 shows a representation similar to FIG. 3 but using the example of FIG

Intercooler and Fig. 9 shows the detail C of FIG. 8.

FIG. 10 shows a perspective view of a part of an intercooler and FIG. 11 shows the detail E from FIG. 10.

Figs. 12 and 13 show an embodiment with a one-piece

Collection box.

FIGS. 14-17 show a further embodiment with grooves in the edges of the collecting box, which serve for embedding the narrow sides of the flat tubes. The embodiments shown are directed to completely made of metal, preferably from suitable aluminum sheets, producible heat exchangers, for example for use in motor vehicles. The aluminum sheets have appropriate solder coatings. After the manufacture and assembly of the individual parts of the heat exchanger and after appropriate pretreatment, these are then joined in a single CAB brazing process (not shown). The heat exchanger consists of wide and narrow sides flat tubes 1 and ribs 2, which form a block and, in the embodiment, of two tube sheets 3 each having at least two deformed longitudinal edges 30 and two collecting tanks 4. In the illustrations, only one side of the heat exchanger has been shown. At the other end of the heat exchanger, not shown, there are therefore a further tube plate 3 and a collecting box 4, which may be formed identically to those shown. At the edges 40 of the collecting box 4 at intervals arranged projections 41 are arranged. The training described so far is known from the prior art. As may best be seen from the illustrations according to FIGS. 1 and 2, mainly from FIGS. 4 and 5 and 6, the narrow sides of the flat tubes λ lie against the substantially vertical longitudinal edges 30 of the tube bottom 3 on the inside. Where the narrow sides abut, there is also a durable and tight connection after soldering, because by this measure, a sufficient Lotangebot is provided. However, so that the plant of the narrow sides can be ensured, the openings 31 must be formed in the tube sheets 3 to directly on the longitudinal edge 30 zoom, which is best seen in FIGS. 6 and 7, because there in the foreground one of the openings 31 to see is, in which no flat tube 1 is yet. In addition, the formed longitudinal edges 30 have been formed as lying below the tube bottom surface 35 channel 30. It was further provided that the above-mentioned projections 41 engage at the edges 40 of the collecting box 4 in the longitudinal edges 30, wherein the projections 41 sit between the flat tubes 1. As can also be seen, in each case two projections 41 each support a flat tube 1 on its broad sides, but directly towards the narrow sides, from. It is understood that during soldering not only a connection of the narrow sides of the longitudinal edge, as already explained above, but also a firm and tight connection the projections 41 in the longitudinal edge 30 and the projections 41 with the flat tubes 1 is made. To allow the latter, it is provided that the dimensions of the distances between the projections 41 correspond approximately to the outer dimensions between the broad sides of the flat tubes 1. The shape of the projections 41 is provided so that the sliding of the projections 41 is facilitated in the distances between the flat tubes 1 on the one hand, on the other hand but also leads to perfect systems both on the flat tubes and in the longitudinal edge 30. The procedure for assembling the heat exchanger, if it does not already result from the above explanations, is the following:

The flat tubes 1 and the ribs 2 are combined to form a flat tube ribbed block. The tube sheets 3 with deformed longitudinal edges 30 are placed at the ends of the flat tubes 1. The collecting boxes 4 are set with their edges 40, on which projections 41 are arranged at intervals, to the edges 30 of the tubesheets 3. The longitudinal edges 30 of the tubesheets 3 are brought into contact with the narrow sides of the flat tubes 1 in the course of the so-called "winding up" of the tubesheets 3. During the subsequent mounting of the collecting boxes 4, the projections 41 are in contact with the longitudinal edges 30 and with the Flat tubes 1 brought, the projections 41 are inserted into the spaces between the flat tubes 1.

Specifically, the projections 41 having longitudinal edges 40 of the collecting tank 4 are internally applied to the edges 30 of the tube sheet 3, wherein the projections 41 are inserted into the spaces between adjacent flat tubes 1. For example, as shown in FIG. 2, the longitudinal edges 30 have been provided with a suitable bevel 33 or the like, so that the edges of the collecting box 4 can be more easily inserted into the longitudinal edges 30 of the tube bottom 3.

To carry out these production steps in series production, auxiliary devices are used which either in principle do not differ from the hitherto customary auxiliary devices or which can be modeled by the person skilled in the art.

For example, as Figs. 1 and 6 further show, it has been provided in these embodiments to reshape not only the longitudinal edges 30 of the tube sheet 3, but also their transverse edges 32. In other not shown Executions remain the transverse edges 32 substantially without deformation, so that the tube sheets 3 can be produced from endless metal strips, which are cut to the required length. Not shown side parts then close the frontal openings of the collecting tanks 4. In Fig. 1, a further alternative was merely indicated. The suggestion consists in only two slots 36 in the opposite longitudinal edges 30 of the tube bottom 3. The slots 36 can be understood as a continuation of the openings 31. In fact, in the otherwise not shown alternative over the entire length of the tube sheet 3, at intervals corresponding to the spacings of the flat tubes 1, such slots 36 are arranged. The narrow sides of the flat tubes 1 sit in these slots 36, so that they are preferably flush with the outside of the formed longitudinal edges 30. The longitudinal edges 40 of the collecting box 4 are then attached from the outside (not shown) to the longitudinal edges 30 of the tube bottom 3. In this alternative case, the longitudinal edges 40 of the collecting box are preferably formed without projections 41.

Figs. 12 and 13 show a possible embodiment of a heat exchanger in which the tube sheet 3 and the collecting box 4 are formed as one piece. This tube sheet / collecting box has a connecting seam, for example a solder joint 45, which is located on the central longitudinal axis of the heat exchanger. As the figures show, the narrow sides of the flat tubes 1 bear against the inside of the longitudinal edges 40 of the tube bottom / collecting tank. The flat tubes are further bordered by the edges of the openings 31 of the inwardly bent tubesheet. This embodiment also has sufficient resistance to thermal cycling for many applications. It is also easy to manufacture.

In contrast to FIGS. 12 and 13, in the exemplary embodiment according to FIGS. 14-17, at least two-part tube plates / collecting boxes were again used. In the longitudinal edges 40 of the collecting box 4 grooves 47 were impressed, which are arranged at intervals corresponding to the distances of the flat tubes 1. Each groove 47 serves to embed a narrow side of the flat tubes 1. Since a solder coating is also present in the grooves 47, very strong solder joints are expected here, and it is expected a relatively higher resistance to thermal cycling.

Claims

claims

1. Heat exchanger, consisting of wide and narrow sides having flat tubes (1) and of ribs (2) forming a block and at least one tube plate (3) / collecting box (4) with at least two deformed, opposite longitudinal edges (30, 40 ), characterized in that at edges (40) of the collecting box (4) spaced projections (41) are arranged, that the narrow sides of the flat tubes (1) against the longitudinal edges (30) of the tube bottom (3) and the collecting box and are connected, wherein the projections (41) engage in the longitudinal edges (30) and sit between the flat tubes (1).

2. Heat exchanger, consisting of wide and narrow sides having flat tubes (1) and ribs (2) which form a block and at least one tube plate (3) / collecting box (4) with at least two deformed, opposite longitudinal edges (30, 40 ), characterized in that the narrow sides of the flat tubes (1) are either embedded in the edges (30 or 40) of the tube bottom / collecting box and connected to the edges or only abut there and are connected without being embedded, wherein the tube bottom (3) and collecting box (4) are formed either in one piece or at least two pieces.

3. Heat exchanger according to claim 2, characterized in that for embedding the narrow sides of the flat tubes (1) spaced grooves (47) or slots are provided in the longitudinal edges.

4. Heat exchanger according to claim 1, characterized in that the projections (41) either in the base of the deformed longitudinal edges (30) are supported or clamped therein.

5. Heat exchanger according to claim 1 or 4, characterized in that the projections (41) are connected both with the longitudinal edges (30) and with the flat tubes (1).

6. Heat exchanger according to claim 1, characterized in that the dimensions of the distances between the projections (41) correspond approximately to the outer dimensions between the broad sides of the flat tubes (1).

7. Heat exchanger according to one of the preceding claims, characterized in that the formed longitudinal edges (30) are formed like a channel, wherein the bottom of the channel (30) below the in the collecting box (4) facing tube bottom surface (35).

8. Heat exchanger according to one of the preceding claims, characterized in that the tube plate (3) has openings (31) for receiving a respective flat tube end (1), wherein the openings (31) into the channel (30) into, immediately to to the edge (30), extend.

9. Heat exchanger according to one of the preceding claims, characterized in that the tube sheets (3) in addition to the formed longitudinal edges (30) also formed edges (32) on the transverse sides thereof.

TO. Heat exchanger according to one of the preceding claims 1 - 8, characterized in that the tube sheets (3) only at the two longitudinal sides deformed edges (30), so that they can be produced from a metal strip with any length.

11. Heat exchanger according to one of the preceding claims, characterized in that the collecting box (4) has frontal openings.

12. Heat exchanger according to one of the preceding claims, characterized in that the heat exchanger has per se known side parts which extend over the length of the flat tubes (1) and close the frontal openings of the collecting tanks (4).

13. Heat exchanger according to one of the preceding claims, characterized in that the projections (41) are shaped so that the insertion thereof between the ends of the flat tubes (1) is supported.

14. Heat exchanger according to one of the preceding claims, characterized in that the heat exchanger is preferably used as an air-cooled intercooler or as Kühlflüssigkeitkühler.

15. A method of manufacturing a heat exchanger comprising the following steps: flat tubes and ribs are combined to form a flat tube rib block; Tubular plates / collecting boxes with shaped longitudinal edges are placed on the ends of the flat tubes, characterized in that the longitudinal edges of the tubesheets are brought into contact with the narrow sides of the flat tubes, that collecting boxes with their edges, at which spaced-apart projections are formed, to the edges the tube sheets are placed, and that the projections are brought into contact with the longitudinal edges and with the flat tubes, wherein the projections are inserted into the spaces between the flat tubes.

16. A manufacturing method according to claim 15, characterized in that the protrusions having longitudinal edges of the collecting tank are preferably applied from the inside to the edges of the tube sheet, wherein the projections are inserted into the spaces between adjacent flat tubes.

17. A method of manufacturing a heat exchanger comprising the following steps: flat tubes and ribs are combined to form a flat tube rib block; Tube sheets / collecting boxes with shaped longitudinal edges are placed on the ends of the flat tubes; characterized in that the longitudinal edges are provided with spaced grooves (47) or slots, and that the narrow sides of the flat tubes are embedded in the grooves or slots.