EP0992757B1 - Header tube for heat exchanger - Google Patents

Description

The invention relates to a heat exchanger, as in the preamble of claim 1 is defined. Such a Heat exchanger is for example from the DE-B-1277282 is known.

Such a heat exchanger is also known from EP 0 845 647 A1 known. In the local manifold is an axial on both sides limited longitudinal slot introduced in the twisted by 90 ° Ends of straight flat tubes of a tube / rib block successively inserted fluid-tight. Owing to Manufacturing tolerances, in particular with regard to the width of the Flat tubes and thus the parallel to the collection tube longitudinal slot Extension of the inserted pipe ends Problems can occur when inserting the pipe ends in the Longitudinal slot result. For example, if the flat tube width for most flat tubes of the tube / rib block at the top Tolerance limit is or even exceeds this the longitudinal extent of the longitudinal slot for this scarce, so that the pipe ends in their entirety difficult in the slot can be inserted. Conversely, the Longitudinal slot rather too long, if the flat tube width is below or below the lower tolerance limit, which increases the risk of leaks in the longitudinal slot after the sealing of the inserted pipe ends results.

The invention is the provision as a technical problem a header pipe unit of the type mentioned, in which the ends of the heat exchanger tubes of a Tube block reliable regardless of manufacturing tolerances fluid-tight in a common longitudinal slot of the manifold can be inserted.

The invention solves this problem by providing a header pipe unit having the features of claim 1. In this header tube unit, the header is characteristically from several frontally nested ones or joined pipes with each before or after the construction of the manifold at least at one Single tube end face open, i. axially opening longitudinal slot manufactured. The actual, to insert the ends the heat exchanger tubes usable length of this way from several aligned single-tube longitudinal slots formed manifold longitudinal slot is not characterized by fixed in advance, but variable over a wide range, sufficient, possibly occurring manufacturing tolerances in the axial extent of the tube ends to be inserted compensate. After inserting all pipe ends in the Longitudinal slot can then be left with the remaining, not occupied by inserted tube ends part of the longitudinal slot be moved in a suitable manner.

For example, this freileged longitudinal slot part subsequently or together with the sealing of the inserted Pipe ends are sealed, or the manifold can with this remaining free longitudinal slot part tightly into a connecting pipe be inserted. Alternatively, one of several Single tubes manufactured collection tube on at least one end side a closed at the outer end single tube include longitudinal slot open only to the inner face, that with its inner face in variable length be nested with a neighboring single tube can, so that the longitudinal slot expansion thereby variably adjustable is. According to the invention thus the ends of the Heat exchanger tubes easily in the common longitudinal slot even if the pipe ends noticeable Show manufacturing inaccuracies.

In a further developed according to claim 2 header pipe unit The manifold includes several extruded, with frontal Floors closed single tubes, with their bottoms are joined together abutting, wherein the collecting tube longitudinal slot preferably after this assembly of the individual tubes is introduced. The interconnected tube sheets then form transverse partitions in the manifold.

In a further developed according to claim 3 header pipe unit is an axially open on both sides longitudinal slot at the respective Single tube provided in this case by bending a previously preferably planed sheet metal part is made. If necessary can bending the sheet metal part to the pipe simultaneously with the insertion of the heat exchanger tube ends done so that the manifold also in the transverse dimension of its longitudinal slot easily to possible manufacturing tolerances of Adjust heat exchanger tube ends in this direction of expansion can. In a further embodiment of this measure are according to Claim 4, the two the longitudinal slot limiting edge surfaces of the sheet metal part shaped so that they each other after the Bending of the sheet metal part to the tube parallel opposite, so that they are flat against mutually parallel, plane outer surfaces can create the inserted heat exchanger tube ends, which favors the stability and tightness of the joint connection.

In a further developed according to claim 5 header pipe unit the longitudinal slot is designed as a passage, i. the longitudinal slot edges have an inwardly or outwardly bent Course on and can in this way the Wärmeübertragerrohrenden absorb elastically when inserting.

A further developed according to claim 6 header tube unit includes a sleeve, on the respective, from the open-mouthed Longitudinal slot slotted Stirnendbereich the manifold the latter can be deferred. With the sleeve can be a after insertion of the heat exchanger tube ends possibly free end of part of the Seal longitudinal slot. In addition, the sleeve stabilizes the Collective tube in operation against bending at high operating pressures an internally flowing heat transfer medium. In a further embodiment of this measure has according to claim 7 the sleeve one only at her in Aufschieberichtung front end open longitudinal slot on, as an import slot for one or more, in the relevant end area inserted in the manifold longitudinal slot heat exchanger tube ends serves. The sleeve can in this case in the area of the inserted with inserted pipe ends of the manifold or the longitudinal slot to be postponed, e.g. until the end stop of the insertion slot against a Wärmeübertragrohrende comes to the plant, so that a possibly left free Part of the open-ended manifold longitudinal slot always be reliably covered by the sleeve can.

In a further developed according to claim 8 header pipe unit the sleeve has a closed bottom, or it is openly designed there and can be attached separately Closing lid are closed. In any case leaves This causes the manifold on the relevant front page close fluid-tight.

In a further developed according to claim 9 header pipe unit is a fastening pin and / or a retaining element on the sleeve, e.g. a retaining flange, molded. This can after attaching the sleeve at the manifold the header tube unit and with her the associated pipe block on the mounting pin or the holding element firmly with another component in the desired Be connected.

In a further developed according to claim 10 header pipe unit the manifold is made of several individual tubes, wherein at least one of the two end-side tubes on its outer Closed on the front and with only one on the inside Front side open longitudinal slot is provided. This end pipe can be variable length with the adjacent one Single tube are plugged together, so that a two-sided closed longitudinal slot with variably adjustable Can provide length by the heat exchanger tubes before the complete nesting and fixing of the two said individual tubes are inserted.

Fig. 1

eine Seitenansicht eines Sammelrohres mit einseitig offenem Längsschlitz,

Fig. 2

eine Seitenansicht eines Sammelrohres mit beidseitig offenem Längsschlitz,

Fig. 3

eine ausschnittweise Draufsicht auf einen Rohr/Rippenblock eines Wärmeübertragers mit seitlicher Sammelrohreinheit,

Fig. 4

eine Seitenansicht einer für die Sammelrohreinheit von Fig. 3 verwendeten Hülse,

Fig. 5

eine Seitenansicht einer modifizierten Hülse für die Sammelrohreinheit von Fig. 3,

Fig. 6

eine Querschnittansicht längs der Linie VI-VI von Fig. 3,

Fig. 7

eine Schnittansicht entsprechend Fig. 6, jedoch für ein Sammelrohr mit als Durchzug gestaltetem Längsschlitz,

Fig. 8

eine Querschnittansicht entsprechend der Linie VIII-VIII von Fig. 3, jedoch mit modifizierter Hülse,

Fig. 9

eine Querschnittansicht entsprechend der Linie IX-IX von Fig. 3, jedoch für eine weitere Hülsenmodifikation,

Fig. 10

eine Längsschnittansicht eines aus zwei Einzelrohren gefertigen Sammelrohres mit beidseitig geschlossenem, variabel einstellbarem Längsschlitz und

Fig. 11

eine teilweise Längsschnittansicht eines aus mehreren, mit geschlossenen Böden aneinandergefügten Einzelrohren aufgebauten Sammelrohres.

Advantageous embodiments of the invention are illustrated in the drawings and will be described below. Hereby show:

Fig. 1

a side view of a manifold with one-sided open longitudinal slot,

Fig. 2

a side view of a manifold with open on both sides longitudinal slot,

Fig. 3

a fragmentary plan view of a tube / fin block of a heat exchanger with side header tube unit,

Fig. 4

a side view of a sleeve used for the manifold unit of FIG. 3,

Fig. 5

3 is a side view of a modified sleeve for the header pipe unit of FIG. 3;

Fig. 6

a cross-sectional view along the line VI-VI of Fig. 3,

Fig. 7

a sectional view corresponding to FIG. 6, but for a collecting tube designed as a passage longitudinal slot,

Fig. 8

a cross-sectional view according to the line VIII-VIII of Figure 3, but with modified sleeve,

Fig. 9

a cross-sectional view along the line IX-IX of FIG. 3, but for a further sleeve modification,

Fig. 10

a longitudinal sectional view of a made of two individual tubes manifold with closed on both sides, variably adjustable longitudinal slot and

Fig. 11

a partial longitudinal sectional view of a constructed of several, with closed bottoms joined together individual tubes manifold.

In Fig. 1, a manifold 1 is shown, which consists of a Circular tube is made in the tube wall an axially extending Longitudinal slot 2 is introduced. The longitudinal slot 2 is closed in a front end region 1a of the collecting tube 1, by standing there at a distance in front of the pipe end in question ends, while in the other manifold end region 1b openly opens.

Fig. 2 shows a manifold 3, which has an axially extending Longitudinal slot 4, which is continuous over the entire Extending collection tube length away and therefore at both Stirnendbereichen 3a, 3b of the manifold opens open. This Collection tube 3 can as a continuous slotted tube or alternatively by round bending a suitably dimensioned Be manufactured sheet metal strip.

Collecting tubes with longitudinal slot open on one or both sides, as shown by way of example in FIGS. 1 and 2, can be used in manifold units for heat exchangers with a tube block comprising a plurality of heat exchanger tubes, in particular for heat exchangers in which flat tubes with twisted tube ends are used as heat exchanger tubes. An example of such a heat exchanger, as it is suitable for a gas cooler or an evaporator of a CO ₂ air conditioning system of a motor vehicle, is shown in sections in Fig. 3. This heat exchanger includes a tube / rib block from a stack of spaced flat tubes 5, are introduced between the thermally conductive corrugated fins 6. The ends 5a of the flat tubes are twisted relative to the flat tube center region by 90 ° about the flat tube longitudinal central axis, wherein the stack spacing of the flat tube center regions is selected equal to the flat tube width, so that the twisted tube ends 5a in a row in touching contact or at least with a very small distance next to each other. By 90 ° -Tordierung the flat tube transverse axis is in the outer part of the twisted flat tube ends 5a parallel to the stacking direction of the tube / rib block and thus parallel to the longitudinal axis 7 of a side of the tube / rib block in this stacking direction or Blockhochrichtung extending manifold 8th

The manifold 8 has in its pipe wall a common Longitudinal slot 9 for the flat tubes 5, in which all on this Block side lying, twisted flat tube ends 5a fluid-tight are inserted. In particular, the manifold 8 of be one of the types shown in FIGS. 1 and 2. Around the collecting tube 8 in its lower in Fig. 3, in which the longitudinal slot 9 opens open depending on the realization or is closed, fluid-tight, is a cup-shaped Sleeve 10 provided on the relevant Stirnendbereich the manifold 8 is pushed. The cup-shaped Sleeve 10 closes on the one hand with its bottom axially open manifold 8 and the other with a corresponding Side wall area an optionally still left, not from an inserted flat tube end 5a filled part of the longitudinal slot 9 from. The fluid-tight Connecting the sleeve 10 with the manifold 8 may be common with the fluid-tight connection of the inserted flat tube ends 5a done with the manifold 8 by means of sealing solder, including the Collection tube 8 may be made of solder-plated material.

The sleeve 10 may, for example, by a thermoforming or Extrusion be prepared. As in the side view of Fig. 4, it has one in the direction of pushing the sleeve 10 on the manifold 8 unilaterally open, i.e. on the opposite side of the case opening slot 11, with the twisted end of the lowest in Fig. 3 flat tube 5b at least partially engages when the sleeve 10 on the manifold 8th is postponed. This corresponds to the width of the insertion slot 11 substantially the thickness of the flat tubes 5. Je according to the length of the sleeve 10 and its insertion slot 11 includes the sleeve 10 in the pushed state in this way a more or less large part of the opening into the manifold 8 End of the lowermost flat tube 5b or alternatively the entire end of the lowermost flat tube 5b and optionally additionally more flat tube ends and so is able to compensate occurring manufacturing tolerances, i. independently of these the required fluid tightness after the sealing soldering to ensure.

Fig. 5 shows a side view of one of those 4 modified sleeve 12, at the bottom of an additional Fastening mandrel 13 is formed, which is used can be, at the finished assembled heat exchanger with the pushed onto the manifold 8 sleeve 12 by suitable, cooperating with the fastening mandrel 13 fastening means to install another component in the desired manner. Moreover, the sleeve 12 has an insertion slot 11a for receiving a corresponding part of the in the longitudinal slot 9 of the manifold 8 inserted series of twisted flat tube ends 5a.

The sleeves 10, 12 can due to the unilaterally open import slot 11, 11 a in each case so far on the manifold 8 be deferred until the bottom in Fig. 3, in the manifold 8 inserted flat tube end against the axial limit the insertion slot 11, 11 a or the manifold 8 with their lower end face against the sleeve bottom to the plant comes. Conveniently, the width of the import slots corresponds 11, 11a substantially the flat tube thickness. In application cases, in which the sleeve only to reach maximum of the outermost flat tube end on the manifold 8 deferred, the slot can be omitted.

When the manifold 8 also on its in Fig. 3, not shown End side is axially closed and / or the longitudinal slot 9 also requires a seal there, can in appropriate Make a second sleeve on this Stirnendbereich be pushed the manifold 8. The respective frontend Sleeve not only ensures the desired tightness, but at the same time prevents the manifold 8, for example, under pressure in use, bends or apart, especially for the or the Stirnendbereiche the manifold 8 is important to which the collecting tube longitudinal slot 9 opens open.

For a good stability and tightness of the connection of the inserted in the collection tube longitudinal slot 9 flat tube ends 5a with the manifold 8, it is advantageous if the edges of the Longitudinal slot 9 guide surfaces for the inserted tube ends Form 5a by abutting flat against the same. Under This aspect advantageous configurations are in Figs. 6 and 7 illustrates. 6 shows a variant, which is particularly suitable for the case that the manifold 8 manufactured by round bending a metal strip is. In this variant, the two lie, the longitudinal slot 9 limiting edge surfaces parallel to each other at a distance opposite, equal to or slightly larger than the thickness the inserted flat tube ends 5a. When manufacturing the manifold 8 from a flat sheet metal strip this means that the two longitudinal slot limiting edge surface preferably before bending the metal strip into a corresponding shape be brought so that they are in the required after bending Distance parallel and not opposite each other inclined.

Fig. 7 shows a variant in which a modified manifold 8a with a passage designed as a longitudinal slot 9a is provided, i. the margins bounding the longitudinal slot 15a, 15b of the manifold wall are radially bent, shown Fall inward, alternatively outward, and thereby form a resilient support for the inserted Flat tube ends 5a. These are the bent edges 15a, 15b at a distance opposite, equal or minor is smaller than the thickness of the flat tubes 5a. The manifold 8a acts like a spring in this case Insert the flat tube ends 5a something expands and inserted Flat tube ends 5a then resiliently holds. This facilitates assembly especially in the event that first the entire tube / rib block and one or more lateral header tube units from manifold 8 and sleeve 10 loose preassembled and then in a common soldering be soldered to a solid heat exchanger structure. At the same time can be by means of this longitudinal slot design as a passage manufacturing tolerances in the thickness of Compensate flat tubes 5a to some extent.

Fig. 8 shows a further variant with respect to the sleeve length staltung, in which an axially open on both sides sleeve ring 16 is pushed onto the manifold 8. The collection tube 8 is in this example, the front side by a final cover acting Ronde 17 closed, which has a nose 17a, which for the fluid-tight closure of the otherwise open ausmündenden Longitudinal slot 9 provides. Visible matches, like also with the other sleeve designs, the inside diameter the sleeve ring 16 is substantially the outer diameter of the Collecting tube 8.

Fig. 9 shows a further realization of a sleeve 18, the the sleeve 12 of Fig. 5 with the exception that in addition to the mounting pin 13 and the insertion slot 11a for a flat tube end 5a received therein, a radial one outwardly projecting mounting flange 19 is formed, about the ready-mounted heat exchanger in the desired Can be set to an associated component, additionally or alternatively to the attachment of a corresponding Component on the mounting pin 13th

Fig. 10 shows an embodiment of one of two nested Single tubes 20, 21 constructed manifold. The outer diameter of the smaller diameter corresponds Tube 20 substantially the inner diameter of the larger diameter Tube 21, so that the former in the latter with coincident longitudinal axes 22 to a desired one Inserted depth and then connected to this fluid-tight, e.g. can be soldered. The two individual tubes 20, 21 are only at their nested front ends 20a, 21a open, at the outer ends 20 b, 21 b, however, with a Floor closed. You can, for example, as first Both sides open tubes are made, each on one Face by rolling to form the said soil be closed.

In the two tubes 20, 21 each have a longitudinal slot 23, 24th introduced, which closed to the outer tube end 20b, 21b is, i. with distance in front of the local tube plate ends while he is on the opposite, inner tube face 20a, 21a opens openly. In the formation of the manifold The two tubes 20, 21, as shown, with aligned longitudinal slots 23, 24 mated, so that the two longitudinal slots 23, 24 together a closed on both sides Collector longitudinal slot result. Whose length is variably adjustable by the two individual tubes 20, 21 more or less intertwined. For manufacturing the heat exchanger will initially be the two individual Tubes 20, 21 only slightly nested, after which then the ends of the heat exchanger tubes loose in the still sufficient long collection tube longitudinal slot can be inserted. In order to the longitudinal slot expansion is sufficient in any case for the two individual tubes 20, 21 expediently a Length of each about 0.6 times to 0.8 times the Block length of the tube block in the vertical direction selected. As soon as then all heat exchanger tube ends are inserted, the both individual tubes 20, 21 completely pushed together, until they abut against the inserted Wärmeübertragrohrenden and the collection tube longitudinal slot of these filled is. In this way, in turn, manufacturing tolerances of Wärmeübertragerrohrenden be easily compensated. Subsequently the loosely assembled composite is fixed, e.g. by means of sealing soldering.

It is understood that as a variant of the example of FIG. 10 between the two shown individual tubes 20, 21 a or several more individual tubes can be provided, each with a continuous, at both ends of the tube opening out Longitudinal slot are provided. In this case, too can be the extent of the longitudinal slots of the individual tubes formed manifold longitudinal slot by variable Nesting at least one outer single tube in variably adjust the adjacent single pipe.

Fig. 11 shows a section of a further example for the realization of a manifold made of several individual pipes. This example is for the entire manifold or at least for the collection tube section shown one Formation of individual tubes 25, 26, 27 provided on both End faces through a respective bottom 25a, 26a, 26b, 27a are closed. The individual tubes 25, 26, 27 are continuous Longitudinal slots 29, 30, 31 and provided with abutting Bottoms 25a, 26a; 26b, 27a and common longitudinal axis 28 so joined together that their longitudinal slots 29, 30, 31 are aligned and a continuous collection tube longitudinal slot result. The individual tubes 25, 26, 27 are preferably made extruded, open on both sides blanks, to which then the front side by rolling the floors 25a, 26a, 26b, 27a are formed. At the adjoining floors 25a, 26a; 26b, 27a, the individual tubes 25, 26, 27 firmly together connected, each with a pair of assembled floors 25a, 26a; 26b, 27a forms a transverse partition wall of the manifold, so that in the longitudinal direction of the collecting tube successive, separate collection rooms are formed. In the floors 25a, 26a, 26b, 27a are through the continuous longitudinal slots 29, 30, 31 corresponding slots introduced, which insert the Include heat exchanger pipe ends in this area can. Preferably, the wall thickness of the tubular jacket is the Individual tubes 25, 26, 27 to the thickness of the frontal bottoms 25a, 26a, 26b, 27a in a ratio of about 2: 1. In this Case then corresponds to the partition wall thickness of the pipe wall thickness.

The examples shown illustrate that the inventive Collecting tube unit with an open at least one side or a variable in length lengthwise slot in the manifold the realization of even under high Operating pressures reliably sealed heat exchangers with a Tube block made possible by several heat exchanger tubes, in a respective end region in the common longitudinal slot of the manifold open. It is understood that the Invention not only the shown, but other realizations includes, e.g. those in which a connecting tube fluid-tight directly connected to the front end of the manifold is. In addition, the invention is not in the case shown rectilinear flat tubes with right-angled twisted ends, but can be used wherever several Heat exchanger tubes end in a common longitudinal slot open a collection tube. It goes without saying that instead of the round tube type shown collecting pipes with others Cross sectional shapes are usable, e.g. those with oval or polygonal cross-section. In all embodiments can also provide one or more partitions in the manifold be to provide several separate collection rooms in this.

In any case, the invention ensures by providing of at least one side open or variably adjustable, the inserted ends of several associated heat exchanger tubes common longitudinal slot a problem-free Compensation of manufacturing tolerances of the inserted tube ends in particular with regard to their extension in the Longitudinal direction of this slot.

Claims (10)

1. A heat exchanger with a pipe block consisting of several heat exchanger pipes and with a collecting pipe unit having a collecting pipe (1) in the pipe wall of which is incorporated a common longitudinal slot (2) into which ends (5a) of the heat exchanger pipes (5) are inserted,
   characterised in that
   the collecting pipe (1) is made of several individual pipes the end faces of which are either inserted into or joined to one another, each having a longitudinal slot (2) which is open at least at one end face (1b) of the individual pipes and made either before or after the assembly of the collecting pipe.
2. A heat exchanger in accordance with claim 1,
   characterised in that
   the collecting pipe contains several extruded individual pipes (25, 26, 27), their end faces closed by means of bases and these bases (25a; 26a; 27a) being butted together and punctured by aligned longitudinal slots (29, 30, 31).
3. A heat exchanger in accordance with claim 1,
   characterised in that
   each individual pipe is made with a longitudinal slot (4) open at both end faces (3a, 3b) by bending a piece of sheet metal.
4. A heat exchange medium in accordance with claim 3,
   characterised in that
   the two edge surfaces (14a, 14b) of the piece of sheet metal which delimit the longitudinal slot are formed such that they lie parallel to the individual pipe after the bending of the piece of sheet metal.
5. A heat exchanger in accordance with one of claims 1 to 4,
   characterised in that
   the longitudinal slot (9a) is designed to puncture the individual pipe.
6. A heat exchanger in accordance with one of claims 1 to 5,
   characterised by
   a sleeve (10) which can be pushed over the end face of the collecting pipe (8) in such a manner as to enclose it.
7. A heat exchanger in accordance with claim 6,
   characterised in that
   the sleeve (10) has an insertion slot open on one side in the direction of pushing.
8. A heat exchanger in accordance with claim 6 or 7,
   characterised in that
   the rear end of the sleeve (10) in the direction of pushing either has a closed base or is open, and in the latter case can be closed by means of a cover (17).
9. A heat exchanger in accordance with one of claims 6 to 8,
   characterised in that
   formed in one piece with the sleeve (18) is a fixing pin (13) and/or a retaining element (19).
10. A heat exchanger in accordance with one of claims 1 to 9,
    characterised in that
    the collecting pipe is made of several individual pipes (20, 21), at least one of the two end pipes being closed at its outer end face (20b, 21b), being provided with a longitudinal slot open only at its inner end face (20a, 21a) and being joined together with the neighbouring individual pipe.

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