EP1042641A1

EP1042641A1 - Heat exchanger tubular block and a multi-chamber flat tube which can be used therefor

Info

Publication number: EP1042641A1
Application number: EP99945950A
Authority: EP
Inventors: Bernd Dienhart; Hans-Joachim Krauss; Hagen Mittelstrass; Karl-Heinz Staffa; Christoph Walter; Jochen Schumm
Original assignee: Ford Werke GmbH
Current assignee: Ford Werke GmbH
Priority date: 1998-07-28
Filing date: 1999-07-09
Publication date: 2000-10-11
Anticipated expiration: 2019-07-09
Also published as: WO2000006964A1; US6523606B1; DE19833845A1; AU5849499A; EP1042641B1; JP2002521644A

Abstract

The invention relates to a heat exchanger tubular block (1) comprising a plurality of block units arranged one behind the other in a direction of the block depth. Said block units each comprise a plurality of heat exchanger tubular units (2) which are successively arranged in a direction of the block height, which comprise tubular channels running in a transversal direction of the block, and which have laterally arranged collection channels (8a-11b) belonging thereto that run in a direction of the block height. According to the invention, at least one collection channel connection (13a, 13b, 13c) is provided between at least two adjacent block units (1). Said collection channel connection directly connects a collection channel of one block unit to a collection channel of the other block unit.

Description

Heat over raσer tube block and a -For usable multi-chamber flat tube

The invention relates to a heat exchanger tube block according to the preamble of claim 1 and to a multi-chamber flat tube that can be used for such a tube block.

The reverse block contains a plurality of block units each consisting of a plurality of stacked pipe units one above the other, the stacking direction defining a block vertical direction and the flow channels formed by the pipe units running in a block transverse direction perpendicular thereto. The block units are arranged one behind the other in the block depth direction perpendicular to the block vertical and block transverse directions. The pipe units open into collecting channels, which run laterally on the pipe block in the block vertical direction, i. H . with a parallel longitudinal axis are arranged. In the present case, the term "collecting channels" is used uniformly for the sake of simplicity for all channels into which the pipe units open, these being collecting channels in the actual sense in which the medium which is carried out in parallel through several pipe units is collected for the purpose of being discharged from the pipe block Distribution channels in which the medium supplied to the pipe block is distributed over several confluent pipe units as well as deflection channels in which the medium is deflected from a first group of pipe units opening into a second group of pipe units opening.

In use, the tube block is flowed through by a first medium, while a second medium to be brought into thermal contact with the first is passed over the tube block in the depth direction of the block with outside flow onto the tube block surfaces. Heat exchangers with such tube blocks are e.g. used as evaporators and condensers in automotive air conditioning systems. The pipe block is usually supplemented into a pipe / fin block by inserting heat-conducting corrugated fins between the pipe units. The tube units can be formed, for example, by flat tubes.

A generic heat exchanger tube block is disclosed in the published patent application DE 39 36 101 AI. The tube block local is composed of single-chamber flat tubes, the U-shape are bent over by 180 ° in the plane of its transversal and longitudinal extension and stacked in the direction perpendicular thereto with the interposition ^'corrugated fin once or meander several times. Depending on the number of flat tube turns, the tube block thus consists of two or more block units located one behind the other in the block depth direction, each of which contains a stack of rectilinear, parallel-flowed flat tube sections. Adjacent block units are in serial fluid communication via the side U-3 arches of the flat tubes. The two ends of each flat tube open on the same side of the block into an associated collecting duct running along the 3lock vertical direction, the two collecting ducts being formed by a longitudinally divided collecting box or two separate collecting pipes.

The invention is a technical problem of providing a heat exchanger tube block of the type mentioned at the outset, with which a heat exchanger with high heat transfer capacity and high pressure stability with a relatively low filling capacity quantity and with the possibility of variable guidance of the temperature control medium passed through, as well as a multi-chamber flat tube which is particularly suitable for the construction of such a tube block.

The invention solves this problem by providing a heat exchanger tube block with the features of claim 1 and a multi-chamber flat tube with the features of claim 11.

In the heat exchanger tube block according to claim 1, at least one collecting duct connection is provided between at least two adjacent block units, which connect a collecting duct of the one block unit directly to a collecting duct of the other block unit. The term "direct" means that the relevant collecting channels are connected via a corresponding fluid connection running in the block depth direction and not or at least not only via one or more of the pipe units of the block. With the help of these one or preferably several direct fluid connections of the collecting channels arranged on the side of the pipe block, a very variable flow control of the medium passed through, adapted to the respective application, for example a refrigerant of an air conditioning system, can be realized. A high heat transfer capacity for the pipe block can be achieved by the several block units lying one behind the other in the 31ock depth direction and thus the flow direction of the other medium passed over the pipe block. The tube block can be constructed from extruded flat tubes with channels optimized with regard to a small filling quantity, ie a small volume of the tube block to be flowed through, and high pressure stability. The collecting ducts arranged on the side of the pipe block can be formed by highly pressure-stable collecting pipes with a relatively small cross-section, in particular if correspondingly narrow flat pipe units or those with the longitudinal direction of the collecting duct flat tube ends turned out from the transverse plane can be used.

In a tube block further developed according to claim 2, direct collecting channel connections between each pair of adjacent block units are provided such that the block units are flowed through in series by the associated temperature control medium.

In a tube block developed according to claim 3 is a collecting space, which e.g. is formed by a collecting pipe or a collecting box, divided into several collecting channels by transverse partition walls. This allows a serpentine flow, once or several times deflected, to flow through a respective block unit.

In still another embodiment according to claim 4 tube block, the collection channels on at least one side of the block of individual, each unit block of the associated header tubes are formed, which are spaced apart in the block depth direction, such as ^"serablauf facilitates Condensation when used in an evaporator. The spacing is brought about by one or more spacer elements which are molded onto or attached to the header tubes.

In further embodiments of this measure, the spacer element according to claim 5 includes a formed sheet metal piece or tube piece with at least one slot opening or according to claim 5, an outwardly bulged passage on a collecting tube. The spacer elements designed in this way keep the manifolds at a distance and at the same time define a respective manifold connection. In a further embodiment of the invention according to claim 7, the spacer element can consist of two passages which abut or engage in one another in a fluid-tight manner, for which purpose at least one of the two passages is bulged outwards. In a tube block further developed according to claim 8, the tube units are formed by straight flat sections which open into the header tubes with twisted tube ends. Due to the twisting at the end, the flat tube ends are twisted out of the transverse plane of the header tubes, which makes it possible to use header tubes with an inner diameter that is smaller than that of the flat tube, in order to keep the inner volume of the tube block low.

A tube block developed according to claim 9 is supplemented to a tube / rib block. For each corrugated fin layer, a single corrugated fin can be introduced, the width of which essentially corresponds to the entire block groove, or several corrugated fins are provided next to one another, which can be of the same or different width and structure.

In a tube block developed according to claim 10, at least two tube units lying next to one another in the block depth direction are realized as integral parts of a one-piece multi-chamber flat tube, for which purpose the width extends over a corresponding number of block units.

The multi-chamber flat tube according to claim 11 is particularly suitable for the construction of a tube block according to claim 10. It is divided at the end by one or more longitudinal slots into a plurality of separate end segments, each of which is twisted about its own longitudinal axis. In the case of a tube block constructed from such flat tubes, the end segments of each flat tube end region are then individually assigned to the corresponding block units, so that the chambers of each flat tube are divided into groups on the corresponding block units, the chambers emanating from an end segment each belonging to a block unit. Advantageous embodiments of the invention are shown in the drawings and are described below. Here show:

1 is a schematic side view of one of several block units of a tube / fin block for an evaporator of an air conditioning system,

FIG. 2 shows a schematic side view of a lateral collecting tube arrangement of the tube / fin block from FIG. 1, FIG.

3 shows a schematic cross-sectional view of a first realization of direct fluid connections between collecting channels of the collecting pipes from FIG. 2,

4 shows a schematic cross-sectional view of a second realization of the collecting duct connections,

5 shows a schematic cross-sectional view of a third realization of the collecting duct connections,

6 shows a schematic cross-sectional view of a fourth realization of the collecting duct connections and

FIG. 7 is a schematic, partial top view of a multi-chamber flat tube that can be used for the tube / fin block of FIG. 1.

1 shows a pipe block unit 1, several of which are arranged one behind the other in the block depth direction, that is to say perpendicular to the drawing plane, and thereby form a pipe / fin block which can be used, for example, as a parallel-flow evaporator with variable refrigerant guidance in a motor vehicle air conditioning system. The respective block unit 1 contains a stack of successive, ie stacked, multi-chamber flat tube units 2 in the block vertical direction, the chambers of which, ie flow channels, in Block cross direction, ie perpendicular to the block depth and block vertical direction. In their end regions 3a, 3b, the flat tube units 2, which otherwise lie in planes perpendicular to the block vertical direction, are twisted by a predeterminable torsion angle about their longitudinal center axis, alternatively about an axis parallel to them. The torsion angle can be chosen as desired between 0 ° and 90 °, with a torsion of 90 ° being selected as an example in FIG. 1. Heat-conducting corrugated fins 6 are introduced between the flat tube units 2.

With their twisted ends 3a, 3b, the flat tube units 2 open into respective header tubes 4a, 5a, which are provided on opposite tube block sides and are arranged with a longitudinal axis parallel to the vertical direction of the block. The flat tube ends 3a, 3b are inserted in a fluid-tight manner in corresponding slots in the header tubes 4a, 5a. In the case of pipe ends twisted by 90 °, these longitudinal slots run parallel to the longitudinal axis of the collecting pipe, which enables the use of collecting pipes 4a, 5a with a particularly small inside diameter. In extreme cases, the latter then only needs to be slightly larger than the thickness of the flat tube units 2. Depending on requirements, the longitudinal slots made on the respective collecting pipe 4a, 5a are separated from one another by narrow webs or are combined to form a continuous longitudinal slot.

FIG. 2 shows an arrangement of four collecting channels 4a, 4b, 4c, 4d lying next to one another parallel in the block depth direction, as are provided on the right side of the tube block in FIG. 1 for the assumed case that the tube block is composed of four block units 1 lying one behind the other. On the opposite side of the tube block, four header tubes are then also arranged correspondingly. The side shown in FIG. 2 forms the connection side of the pipe block, whereby for the flow direction selected in FIGS. 1 and 2, illustrated by flow arrows, the medium passed through the pipe block is fed to the collecting pipe 4 a on the left in FIG. 2 and from the one shown in FIG. 2 right collective pipe 4d is discharged again. It is understood that alternatively the opposite flow direction is possible. The header pipes 4a to 4d shown in FIG. 2 are each divided into two separate header channels 8a, 8b by a transverse partition 7a to 7d; ^' 9a, 9b; 10a, 10b; 11a, 11b divided. In contrast to this, the opposite collecting tubes are undivided and therefore each form a single collecting channel 12, as illustrated in FIG. 1 on the left collecting tube 5aa. This has the consequence that the undivided manifolds on the left side of the block in FIG. 1 act as deflecting tubes, which deflect that from one part of the flat tube units, which open in parallel on the opposite side into the one collecting duct 8a, into the other part of the flat tube units, which open opposite to the other collecting channel 8b. This flow behavior can also be seen in FIG. 1.

To the flow medium from a. forward to a next block unit, i.e. the block units must be connected serially in terms of flow technology. A collecting duct connection 13a, 13b, 13c is provided between each two adjacent ones of the four collecting pipes 4a to 4d of FIG. 2, in which a direct fluid connection is created in the block depth direction between the associated flow ducts. The collecting duct connections 13a to 13c, as can be seen from FIG. 2, are arranged alternately in such a way that of the two collecting ducts of each inner collecting pipe 4b, 4c, one with the neighboring collecting duct of a collecting pipe adjacent on one side and the other with the adjacent collecting duct of a collecting pipe adjoining on the other side is connected. In this way, the temperature control medium is guided serially through the block units located one behind the other, whereby it flows through each block unit in a meandering manner.

In the flow profile shown in FIGS. 1 and 2, the temperature control medium reaches the associated collecting duct 8a of one end via a lateral inlet opening 14 Manifold 4a. This collecting duct 8a functions as a distributor, which divides the medium into the first part of parallel flat tube units 2 of the block unit 1 in question which flows into it. After flowing through this group of flat tube units 2, the medium reaches the opposite Sarnmel or deflection tube 5a, where it is deflected in the remaining part of the flat tube units 2 of this block unit 1, in order to pass through these flat tube units into the other collecting duct 8b of the inlet-side collecting tube 4a stream. From there, the medium is forwarded via the corresponding collecting duct connection 13a into the adjacent collecting duct 9a of the adjacent collecting pipe 4b and thus to the next block unit. This block unit flows through it, as can be seen from FIGS. 1 and 2, in the. Flow through the first, inlet-side block unit in opposite directions. The flow directions are further illustrated in FIG. 2 by the fact that in those collecting channels in which the temperature control medium is passed on to the drawing plane, the crossed circles customary for this are drawn in, while in the other collecting channels which act as collectors and into which the medium enters the drawing plane from behind, the usual dotted circles are drawn. After flowing through the second block unit, the medium thus arrives in the collecting collecting duct 9b of this block unit and is forwarded from there to the distributing, neighboring collecting duct 10a via the corresponding collecting duct connection 13b to the next block unit. This third block unit is then again flowed through in the same direction as the first block unit. From its collecting channel 10b, the medium passes through the associated channel connection 13c to the fourth block unit, which in turn flows through in the same way as the second block unit. The temperature control medium is then discharged from the tube block via an end outlet 15 from the collecting collecting channel 11b of the fourth block unit. It goes without saying that, as an alternative to this example 1, fewer or more than four block units can also be connected in series in the manner described. Furthermore, it goes without saying that the shape and positioning of the inlet and outlet openings can be modified as desired in relation to the example shown in order to supply the temperature control medium to the pipe block in a manner which is best adapted to the respective application and to discharge it again from there. As a further alternative, additional transverse partition walls can be provided in the header pipes on both sides of the respective block unit in order to guide the temperature-control fluid through the block unit in a meandering manner with repeated reversal of direction. Another modification is to provide the inlet and outlet openings not on the same as shown, but on opposite pipe block sides.

As indicated in the schematic view of Fig. 2, the header pipes 4a to 4d are arranged on the respective pipe block side at a distance from one another, which e.g. when used as an evaporator, the condensate drainage easier. This is achieved with spacer elements 16a, 16b, 16c, which simultaneously provide the direct collecting channel fluid connections 13a, 13b, 13c. Various implementations for this are shown in FIGS. 3 to 6. In the example of FIG. 3, a suitably shaped tubular sleeve 17 is provided as a spacer element, which is provided at two radially opposite points on its circumference with longitudinal slots 18a, 18b, the slot edges of which form connecting pieces which are inserted in a fluid-tight manner in corresponding longitudinal slots of two header pipes 19a, 19b to be connected are. The tubular sleeve 17, which thus forms a tubular transition piece, is closed and fixed at the end: the two fluid-connected header tubes 19a, 19b at the desired distance.

In the example of FIG. 4, a suitably shaped, solder-plated sheet metal piece 20 is used as a spacer element, into which an opening 21 is made, which adjoins with longitudinal slots 22, 23. the collecting pipes 24, 25 forms a continuous fluid connection between the collecting channels defined by the collecting pipes 24, 25. Furthermore, two flat tubes 2a, 2b of adjacent tube block units are shown in FIG. 4, which are inserted with correspondingly twisted tube ends into corresponding longitudinal slots of the header tubes 24, 25 in a fluid-tight manner. As indicated by appropriate flow arrows, the temperature control medium flows from a flat tube 2a and possibly further parallel flat tubes of the same block unit into the collecting channel of the associated collecting tube 24 and is forwarded via the direct collecting channel connection into the collecting channel of the adjacent collecting tube 25 and then into there distributed flat tubes 26 of the next tube block unit concerned.

The definition of the solder-plated sheet metal piece 20 to the manifolds 24, 25 is carried by ^'a suitable soldering, the previous solder plating can be performed by any conventional method, for example by galvanizing, or the so-called CD method. A common soldering process can be provided both for connecting the spacer elements 20 to the header tubes 24, 25 and for the fluid-tight connection of the flat tube units to the header tubes 24, 25, for which purpose the flat tubes and / or the header tubes are also prefabricated with solder and provided with flux. Alternatively, unplated manifolds 24, 25 can be used and separate molded solder parts can be introduced at the connection points. The fluid-connected manifolds 24, 25 are also kept at a desired distance from one another with the spacer elements 20 used in the example of FIG. 4.

5 and 6 show examples in which the spacer elements themselves are formed by corresponding bulges on the connected manifolds. In the embodiment of FIG. 5, collecting tubes 26, 27 are used, which are provided with dome-shaped bulges 28, 29 at the connection points are, which surround a respective through opening 30, 31. The header pipes 26, 27 to be connected are joined together with their dome-shaped bulges 28, 29 in a fluid-tight manner so that the desired fluid connection is obtained there and the header pipes 26, 27 are kept at a distance in the area outside the connection point as desired.

In the example of FIG. 6, header pipes 32, 33 to be connected to one another are provided with different, intermeshing dome-shaped bulges 34, 35, which surround associated through openings. The narrower bulge 35 is inserted into the corresponding bulge 34 of greater width and fixed in it in a fluid-tight manner, preferably by means of sealing soldering.

In all of the examples described, in the prefabrication of the required manifolds, the slots required for inserting the tube units can be made in one operation with the slots required for the direct manifold fluid connection, i.e. Passages, and possibly the associated dome-shaped bulges are generated. The passages for the direct collecting channel fluid connections can be round or elongated. The two dome-shaped bulges forming a respective collecting channel-fluid connection do not need, as in the examples shown, both to be bulged outwards, but alternatively one of the two can be bulged inwards, in which the other bulge facing outwards engages.

As indicated in FIG. 4, the flat tube units 2 of the tube / fin block from FIG. 1 can consist of flat tubes 2a, 2b lying next to one another in the block depth direction, for each block unit 1, ie in this case each block unit 1 consists of a stack of individual flat tubes, whose width corresponds essentially to the depth of the respective block unit. Alternatively, a wider type of flat tube can be ner manner can be used, as is schematically and partially illustrated in Fig. 7. The multi-chamber flat tube 2c shown there has a width T which essentially corresponds to the total tube block depth, ie the sum of the depths of the individual block units. The flat tube 2c is in both end regions, of which in., Fig. 7 is shown, provided with a predeterminable number n of longitudinal saw cuts 36- _L , 36 ₂ , 36 ₃ , ie n = 3 cuts in this example, as a result of which the end region is divided into a number n + 1 of end segments 37 _x to 37 ₄ , ie divided into four segments in the case shown. Each end segment 37 _x to 37 ₄ is twisted by 90 ° about its own longitudinal central axis, alternatively a different torsion angle greater than 0 ° and less than 90 ° can be selected. In the case of right-angled twisting, the end segments 37 _x to 37. run on their end faces parallel to the vertical direction of the block, ie to the longitudinal direction of the associated header pipes 38 _1; 3 ^" 8 ₂ , 38 ₃ , 38 ₄ , which are provided with corresponding longitudinal slots, into which the end segments 37 _x to 37 _{4 are} inserted. In this way, the flat tube 2c is flow-technically into a corresponding number n of flat tube strands 2 _{according to} 2 ₂ , 2 ₃ , 2 ₄ which each belong to one of the block units one behind the other in the block depth direction and contain an associated subgroup of all flow channel-forming chambers of the flat tube 2c, while in the example of Fig. 7 the flat tube 2c is divided into partial strands 2 _X to 2 _{4 of the} same width , may alternatively be a division be provided in different widths partial strands. in the example of Fig. 7 remains between two adjacent flat tube parts per an open flow channel 39 by being the end of the corresponding wide chosen saw cuts _36!, 36 _2, 36 ₃ reduced and thereby does not act as a fluid-carrying channel that opens into the collecting pipes If saw cuts are made as narrow cuts between adjacent channels, all chambers of the flat tube 2c can function as fluid-conducting flow channels if required. The multi-chamber flat tube 2c is preferably manufactured as an extruded profile with channels optimized with regard to a small internal volume and high pressure stability. To achieve a low internal volume and a high pressure stability of the tube / fin block overall, as mentioned, additionally contributes to the fact that bei collecting tubes especially for flat tubes with twisted ends for the tube block. relatively small inner diameter can be used. In addition, depending on the positioning of the direct ^' collecting duct connections between the collecting pipes and / or the transverse partition walls in the collecting pipes, a very variable flow guidance for the temperature control medium passed through can be achieved.

In order to form the corrugated fin structure 6 of the tube / fin block, one corrugated fin extending over the entire block depth or several narrower corrugated fins of the same or different can be used for each fin layer. Width must be placed side by side. For example, a wide corrugated fin extending over three block units and a narrow corrugated fin limited to the fourth block unit or alternately a narrower and a wider corrugated fin can be provided. The various possibilities for introducing the corrugated fins 6 are independent of whether the wide flat tube 2c of FIG. 7 or a plurality of flat tubes lying side by side in the block depth direction are provided.

The pipe block according to the invention is u. a. Particularly good for evaporators of automotive air conditioning systems working with the refrigerant C0 ₂ , in that it is sufficiently pressure-stable and has a comparatively small internal volume, whereby besides the already mentioned further realizations are possible. So z. B. Collecting pipes without cross dividers may be provided, d. H . all pipe units of a 3lock unit are flowed through in parallel. In this case, the manifold connections are alternately arranged on one and the other manifold tube block side. As a further variant NEN the collecting channel connections are formed by deflecting tubes, which deflect the medium flowing through from tube units of a block unit into the tube units of at least one adjacent block unit. For this purpose, these tube units of the block units involved then open into a common uranium steering space formed by the deflection tube, which thus integrally comprises the connected collecting channels of these block units.

Claims

claims

1. heat exchanger tube block, with a plurality of block units (1) lying one behind the other in the block depth direction, each having a plurality of heat exchanger tube units (2) which follow one another in the block vertical direction with pipe flow channels running in the transverse direction of the block and associated collecting channels (8a to 11b) arranged laterally and running in the block vertical direction include, characterized in that between at least two adjacent block units (1) at least one collecting channel connection (13a, 13b, 13c) is provided, which connects a collecting channel of one block unit directly to a collecting channel of the other block unit.

2. Heat exchanger tube block according to claim 1, further characterized in that at least one collecting duct connection

(13a, 13b, 13c) is provided between each pair of adjacent block units (1) in such a way that a flow path serially connecting the block units is formed.

3. Heat exchanger tube block according to claim 1 or 2, further characterized in that at least on one side of the block units (1) a multi-part collecting space is provided which has a plurality of collecting channels (8a to 11b) separated from one another by a respective transverse partition (7a to 7d) ) includes.

4. Heat exchanger tube block according to one of claims 1 to 3, further characterized in that the collecting channel or channels (8a to 11b, 12) of each block unit (1) on at least one block side of individual collecting tubes (4a to 4d, 5a) which are spaced apart from one another by at least one integrally formed or attached spacer element (16a, 16b, 16c).

5. Heat exchanger tube block according to claim 4, further characterized in that the spacer includes a formed Blechstüc.k (20) or pipe section (17) with at least one slot opening to provide the respective collecting duct connection.

6. Heat exchanger tube block according to claim 4, further characterized in that the spacer includes an outwardly bulged passage (28, 29, 34, 35) on one or both connected manifolds (26, 27, 32, 33), the Part of the manifold connection between the two manifolds.

7. Heat exchanger tube block according to claim 6, further characterized in that the spacer consists of two fluid-tight abutting or interlocking passages (28, 29, 34, 35) forming the collecting channel connection, at least one of which bulges outwards.

8. Heat exchanger tube block according to one of claims 1 to

7, further characterized in that the heat exchanger tube units are formed by rectilinear flat tube strands (2) which are inserted with twisted tube ends (3a, 3b) into corresponding slots (4a, 5a) forming manifold-forming tubes, forming channels that form perpendicular or inclined to the 31ock depth direction.

9. Heat exchanger tube block according to one of claims 1 to

8, further characterized in that thermally conductive corrugated fins (6) are introduced between the heat exchanger tube units (2), a corrugated fin extending over the entire block depth or several adjacent corrugated fins of the same or different width and the same or different fin density being provided in the block depth direction .

10th Heat exchanger tube block according to one of claims 1 to ^■ 9, further characterized in that at least two juxtaposed in block depth direction Wärmeübertrager- tube units one behind the other block units of integral parts of the same or different width a extending in the block depth direction over a plurality of block units multi-chamber flat tube are formed.

11. Multi-chamber flat tube for a heat exchanger tube block, in particular a heat exchanger tube block according to claim 10, characterized in that it ends at one end by means of one or more longitudinal slots (36 _1; 36 ₂ , 36 ₃ ) into a plurality of separate end segments (37 _x to 37 ₄ ) is subdivided, each twisted around its own longitudinal axis.