EP1717530A2 - Heat exchanger, more particularly rear evaporator for automotive vehicle - Google Patents

Abstract

The exchanger has pipes and an accumulator box having a distribution plate and a base plate, where the exchanger flows through a cooling medium. The inflow of the cooling medium into the heat-exchanger is distributed by a distributing device on two strands that are separated from each other in such a manner that the flow comes to non mutual stirring of a cooling medium partial flow. The partial flow runs in the medium flow. An independent claim is also included for a heat exchanger arrangement comprising a heat exchanger.

Description

The invention relates to a heat exchanger, in particular a rear evaporator for a motor vehicle, according to the preamble of claim 1 or 2.

From the DE 102 60 107 A1 a heat exchanger is known which has tubes which can be flowed through by a first medium along a plurality of hydraulically parallel flow paths constructed from sections (flat tubes) and by a second medium. The heat exchanger has an inlet and an outlet section, wherein in each case a plurality of spaced-apart refrigerant inlet and outlet openings is provided in the inlet or outlet section. Through the refrigerant inlets, the refrigerant is distributed from the corresponding collection chamber to the flow paths, and through the Käftemittelauslässe the refrigerant is collected in the corresponding collection chamber and fed to the outlet section.

In Heckverdampfern is often the expansion element in the front of the vehicle (eg in the front of the engine compartment or in the cabin bulkhead), so that expanded refrigerant in the two-phase state long lines, if necessary over 2 m, must be led to the rear to the rear evaporator. Due to the length of the line, this leads to problems with regard to segregation of the gas and liquid phase. If the rear evaporator is operated superheated, it may occur in conventional designs that individual strands are preferably supplied with the segregated gas fraction, so that an unfavorable temperature profile can occur, whereby the performance and efficiency of the rear evaporator are impaired. This also applies, for example, in the case of a construction of the rear evaporator according to the aforementioned DE 102 60 107 A1 to.

An uneven temperature distribution is particularly undesirable in the generally relatively small designed Heckverdampfern (eg. 10 cm high and 15 cm wide), which are used in particular in high-quality, multi-zone air conditioning, the rear evaporator cooling the two zones, since they comfort can seriously affect the occupants.

It is therefore an object of the invention to provide a heat exchanger with an improved temperature profile available, so that even when separated at the heat exchanger inlet two-phase, i. not as a fine mist, refrigerant present a uniform temperature distribution can be ensured.

This object is achieved by a heat exchanger with the features of claim 1 and claim 2. Advantageous embodiments are the subject of the dependent claims.

For this purpose, a heat exchanger, in particular a rear evaporator for a motor vehicle is proposed, which can be flowed through by refrigerant, and which is constructed such that the refrigerant flowing into the heat exchanger refrigerant flow through a distributor to at least two from each other separated strands is distributed, such that there is no mutual mixing of each flowing therein refrigerant partial flow. A combination of the refrigerant partial streams, in particular in the output region of the heat exchanger should not be excluded. This configuration makes it possible, in particular in cases when the refrigerant is in a two-phase, segregated state at the evaporator inlet, a uniform temperature distribution across the heat exchanger, and thus also the largest possible cooling capacity with small dimensions of the heat exchanger. In other evaporators, such a two-phase, demixed refrigerant usually leads to a highly non-uniform temperature profile. By the uniform distribution of refrigerant so the comfort of the rear vehicle occupants can be significantly increased, the measures for this are very inexpensive. The above applies in particular to R744 (carbon dioxide) as a refrigerant, since it has been shown that the temperature distribution can be homogenized particularly well here.

According to another aspect of the invention, there is provided a heat exchanger, in particular a rear evaporator for a motor vehicle, comprising pipes and a collecting box comprising a distributor plate, a baffle and a bottom plate in which the tubes terminate with at least one of their ends and that of refrigerant can be flowed through, wherein the collecting box has exactly one opening in the distributor plate, passes through which refrigerant into the collecting box and directly after which the refrigerant flow is distributed to at least two strands. The refrigerant distribution is preferably uniformly to exactly two strands. The uniform distribution of refrigerant due to the one opening in the distributor plate provided with an injection manifold opening in the deflector plate arranged thereafter allows even distribution of the refrigerant, especially when the refrigerant is in a two-phase demixed state, in others Evaporate to a strong inconsistent temperature profile leads. Due to the uniform distribution of refrigerant so the comfort of the rear vehicle occupants is significantly increased, the measures for this are very inexpensive. The above applies in particular to R744 (carbon dioxide) as a refrigerant, since it has been shown that the temperature distribution can be homogenized particularly well here.

The two above-mentioned aspects of the invention are individually and independently advantageous. Conceivable, however, are combinations of these aspects.

The injection distributor opening adjoining the opening in the distributor plate is preferably H-shaped. This form allows in a particularly simple and cost-effective manner a uniform distribution of the refrigerant on the two strands.

The baffle preferably has not only an H-shaped injection manifold opening but also a plurality of H-shaped openings for deflecting the flow of refrigerant from one pipe to the adjacent pipe. Due to the H-shaped configuration, the refrigerant is mixed with each deflection in the collecting box, so that the temperature profile on the flat tubes itself is very even.

The baffle preferably also has an H-shaped refrigerant outlet opening, which is arranged after the corresponding opening in the distributor plate and through which the refrigerant is sucked out of the collecting box. The symmetrical design of the outlet opening supports a uniform temperature profile.

The H-shaped opening is designed to guide and optimize the flow with rounded corners.

The H-shaped opening is preferably formed rounded at its leg ends, wherein the width of the leg slightly widened. The leg itself preferably ends straight.

The H-shaped opening preferably has a leg width which corresponds approximately to the width of the transverse connection between the two legs. On the one hand, this embodiment enables a good mixing of the refrigerant in the region of the deflection and, on the other hand, it enables a sufficiently resilient design and solubility of the deflection plate.

The heat exchanger is preferably designed in two rows, wherein it is preferably also built very small.

In order to enable the most uniform possible temperature profile and a good efficiency of the heat exchanger, the injection manifold opening - seen in the flow direction of the heat exchanger through the air flowing - preferably arranged in the last row of tubes. Accordingly, the outlet opening is opposite on the other side, i. in the - viewed in the flow direction of the heat exchanger through the air flowing - arranged first row of tubes.

The heat exchanger is, in order to obtain a uniform temperature profile as possible, preferably mirror images to the central transverse axis and / or point symmetrical to the central axis formed, wherein - in the case of an unsuitable number of tubes - the corresponding inlet and outlet openings can also be arranged offset by one row. In the case of an asymmetrical air inflow, however, it may also be advantageous to provide a different path length of the two strands through which the refrigerant flows through the heat exchanger. The same applies in other cases, for example, if due to the evaporator width or due to the installation conditions no symmetrical division is possible.

The injection tube and / or the suction tube are preferably soldered to the heat exchanger, resulting in a complete solution with as few soldering / connecting points. The soldering - including the collecting box - can be done in one step, so that the manufacturing costs can be minimized.

The connection points for the injection and suction pipe are preferably connected to the same center with respect to the width of the heat exchanger. In this case, preferably at least one, in particular both tubes run parallel to the direction of air flow.

A heat exchanger arrangement, in particular for a rear evaporator of a motor vehicle, has at least one heat exchanger, preferably at least one heat exchanger, as described above, through which refrigerant of a refrigerant circuit can flow, and lines via which refrigerant can be supplied to and discharged from the heat exchanger the heat exchanger in a through a closed wall, which hereinafter not necessarily perpendicular walls, but also horizontally extending areas are understood, arranged separate from the environment interior, the other refrigerant circuit - apart from extending in the heat exchanger part - outside of the interior is designed to extend , And the connection points of the lines to the heat exchanger by means of at least one fixed to the heat exchanger flange, which is arranged in an opening in the wall, au Are arranged outside of the interior. By providing a sealed in an opening of the wall flange, which relocates the connection points to the outside, the assembly is simplified. Furthermore, the interior, So in particular the vehicle interior and the occupants located therein, protected from leaks from the connection points or lines, which are formed in conventional interior air conditioning in the vehicle interior or at least partially extending in the interior.

The sealing of the opening is preferably carried out by an inserted between the heat exchanger and the wall sealing element, which may be formed, for example, by a foam element, which can also compensate for certain unevenness and dimensional variations, without affecting its function.

In the wall in which the opening is formed for the flange, it handles preferably around the vehicle floor, so that the heat exchanger is supplied from below.

The opening for the flange is preferably arranged adjacent to a condensate drain for the condensate collecting in the heat exchanger.

In Kaftemittelkreislauf CO ₂ is preferably provided as a refrigerant, but also any other refrigerant can be used.

The flange and / or the heat exchanger have at least one nub, which is mounted in a recess or opening of the heat exchanger or flange, in particular is pressed. This allows a simple prefixing, so that simplifies the further assembly of the heat exchanger.

Preferably, the flange is firmly soldered to the heat exchanger. In this case, the soldering of the flange with the corresponding surface of the heat exchanger is preferably carried out in one operation with the actual Solder the heat exchanger, so that only one soldering process is required, which energy and time and thus manufacturing costs can be saved.

The flange is preferably arranged on the heat exchanger base at a collection or distribution box. In this case, the collection or distribution box as well as the flange preferably flat surfaces, which are brought into abutment against each other and firmly connected, so that a secure and tight connection of the flange and heat exchanger can be ensured.

Fig. 1

eine Ansicht eines Heckverdampfers mit Expansionsventil, Einspritzrohr und Saugrohr,

Fig. 2

eine Seitenansicht des Heckverdampfers von Fig. 1 mit Expansionsventil, Einspritzrohr und Saugrohr,

Fig. 3

eine Ansicht von unten auf den Heckverdampfer von Fig. 1 mit Expansionsventil, Einspritzrohr und Saugrohr,

Fig. 4

eine Ansicht des Einspritzrohres,

Fig. 5

eine Ansicht von unten auf das Einspritzrohr von Fig. 4,

Fig. 6

eine vergrößerte Darstellung eines Schnitts entlang der Linie VI-VI von Fig. 4,

Fig. 7

eine Detailansicht des Bereichs VII von Fig. 6,

Fig. 8

eine Darstellung eines Schnitts entlang der Linie VIII-VIII von Fig. 7,

Fig. 9

eine Ansicht des Saugrohrs,

Fig. 10

eine Ansicht von unten auf das Saugrohr von Fig. 9,

Fig. 11

eine vergrößerte Darstellung eines Schnitts entlang der Linie XI-XI von Fig. 10,

Fig. 12

eine Detailansicht des Bereichs XI von Fig. 11,

Fig. 13

eine Darstellung eines Schnitts entlang der Linie XIII-XIII von Fig. 12,

Fig. 14

eine Draufsicht auf die Verteilerplatte des Heckverdampfers von Fig. 1,

Fig. 15

einen Schnitt entlang der Linie XV-XV von Fig. 14,

Fig. 16

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 1,

Fig. 17

eine Detailansicht des Bereichs XVII von Fig. 16,

Fig. 18

eine Seitenansicht des Umlenkblechs von Fig. 16,

Fig. 19

eine Draufsicht auf die Bodenplatte des Heckverdampfers von Fig. 1,

Fig. 20

eine Seitenansicht der Bodenplatte von Fig. 19,

Fig. 21

eine Ansicht der Anschlüsse einer Variante eines Heckverdampfers mit einer Breite von zwölf Flachrohren,

Fig. 22

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 21 mit durch Pfeilen angedeutetem Strömungsverlauf,

Fig. 23

eine erste Variante der Anschlüsse für den Heckverdampfer von Fig. 21,

Fig. 24

eine zweite Variante der Anschlüsse für den Heckverdampfer von Fig. 21,

Fig. 25

eine dritte Variante der Anschlüsse für den Heckverdampfer von Fig. 21,

Fig. 26

eine Ansicht der Anschlüsse einer zweiten Variante eines Heckverdampfers mit einer Breite von zwölf Flachrohren,

Fig. 27

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 26 mit durch Pfeilen angedeutetem Strömungsverlauf,

Fig. 28

eine erste Variante der Anschlüsse für den Heckverdampfer von Fig. 26,

Fig. 29

eine zweite Variante der Anschlüsse für den Heckverdampfer von Fig. 26,

Fig. 30

eine dritte Variante der Anschlüsse für den Heckverdampfer von Fig. 26,

Fig. 31

eine Ansicht der Anschlüsse einer dritten Variante eines Heckverdampfers mit einer Breite von zwölf Flachrohren,

Fig. 32

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 31 mit durch Pfeilen angedeutetem Strömungsverlauf,

Fig. 33

eine Ansicht der Anschlüsse einer Variante eines Heckverdampfers mit einer Breite von zehn Flachrohren,

Fig. 34

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 33 mit durch Pfeilen angedeutetem Strömungsverlauf,

Fig. 35

eine Variante der Anschlüsse für den Heckverdampfer von Fig. 33,

Fig. 36

eine Draufsicht auf das Umlenkblech eines Heckverdampfers mit einer Breite von acht Flachrohren mit durch Pfeilen angedeutetem Strömungsverlauf ,

Fig. 37

eine Draufsicht auf das Umlenkblech eines Heckverdampfers mit einer Breite von acht Flachrohren mit durch Pfeilen angedeutetem Strömungsverlauf gemäß einer Anschlussvariante bezüglich des Heckverdampfers von Fig. 36,

Fig. 38

eine Ansicht der Anschlüsse einer Variante eines Heckverdampfers mit zwölf Flachrohren, bei dem die beiden Stränge unterschiedlich lang sind,

Fig. 39

eine Draufsicht auf das Umlenkblech des Heckverdampfers von Fig. 38,

Fig. 40

eine weitere Variante der Anschlüsse für den Heckverdampfer,

Fig. 41

eine Fig. 40 entsprechende Variante der Anschlüsse für den Heckverdampfer mit umgekehrter Durchströmungsrichtung,

Fig. 42

eine weitere Variante der Anschlüsse für den Heckverdampfer,

Fig. 43

eine Ansicht auf einen Fahrzeugboden im Bereich der Anordnung eines Wärmeübertragers von unten mit einer Detailansicht eines Teilbereichs,

Fig. 44

einem Schnitt durch Fig. 43 entlang Linie A-A mit einer Detailansicht eines Teilbereichs,

Fig. 45

eine Frontalansicht des Wärmeübertragers samt Flansch in Richtung des Pfeiles III von Fig. 47,

Fig. 46

eine Ansicht des Wärmeübertragers mit Flansch in Richtung des Pfeiles IV von Fig. 45,

Fig. 47

eine Seitenansicht des Wärmeübertragers mit Flansch in Richtung des Pfeiles V von Fig.45,

Fig. 48

einen Schnitt entlang Linie VI-VI von Fig. 46,

Fig. 49

eine perspektivische Ansicht des Flansches zur Verdeutlichung der Anschlüsse,

Fig. 50

eine perspektivische Ansicht des Flansches aus der entgegengesetzten Richtung,

Fig. 51

eine perspektivische Ansicht des auf die Bodenplatte aufgesetzten Flansches,

Fig. 52

einen ausschnittsweisen Schnitt durch den Flansch, die Verteilerplatte, das Umlenkblech und die Bodenplatte in Längsrichtung des Wärmeübertragers,

Fig. 53

eine perspektivische Ansicht des Umlenkblechs,

Fig. 54

eine Detailansicht eines Ausschnitts des Umlenkblechs von Fig. 53,

Fig. 55

eine perspektivische Ansicht der Bodenplatte, und

Fig. 56

eine perspektivische Ansicht der Verteilerplatte.

In the following the invention will be explained with reference to an embodiment with several variants with reference to the drawings in detail. In the drawing show:

Fig. 1

a view of a rear evaporator with expansion valve, injection pipe and intake manifold,

Fig. 2

1 is a side view of the rear evaporator of FIG. 1 with expansion valve, injection tube and intake manifold,

Fig. 3

3 is a bottom view of the rear evaporator of FIG. 1 with expansion valve, injection tube and intake manifold, FIG.

Fig. 4

a view of the injection tube,

Fig. 5

a bottom view of the injection tube of Fig. 4,

Fig. 6

an enlarged view of a section along the line VI-VI of Fig. 4,

Fig. 7

a detailed view of the area VII of Fig. 6,

Fig. 8

4 is a view of a section along the line VIII-VIII of FIG. 7;

Fig. 9

a view of the suction tube,

Fig. 10

a bottom view of the suction tube of Fig. 9,

Fig. 11

an enlarged view of a section along the line XI-XI of Fig. 10,

Fig. 12

a detailed view of the area XI of Fig. 11,

Fig. 13

3 is a view of a section taken along the line XIII-XIII of FIG. 12;

Fig. 14

1 is a top view of the distributor plate of the rear evaporator of FIG. 1,

Fig. 15

a section along the line XV-XV of Fig. 14,

Fig. 16

a top view of the baffle of the rear evaporator of Fig. 1,

Fig. 17

a detailed view of the area XVII of Fig. 16,

Fig. 18

a side view of the baffle of Fig. 16,

Fig. 19

1 is a plan view of the bottom plate of the rear evaporator of FIG. 1,

Fig. 20

a side view of the bottom plate of Fig. 19,

Fig. 21

a view of the connections of a variant of a rear evaporator with a width of twelve flat tubes,

Fig. 22

a plan view of the baffle of the rear evaporator of Fig. 21 with flow indicated by arrows,

Fig. 23

a first variant of the connections for the rear evaporator of Fig. 21,

Fig. 24

a second variant of the connections for the rear evaporator of Fig. 21,

Fig. 25

a third variant of the connections for the rear evaporator of Fig. 21,

Fig. 26

a view of the connections of a second variant of a rear evaporator with a width of twelve flat tubes,

Fig. 27

a top view of the baffle of the rear evaporator of Fig. 26 with flow indicated by arrows,

Fig. 28

a first variant of the connections for the rear evaporator of Fig. 26,

Fig. 29

a second variant of the connections for the rear evaporator of Fig. 26,

Fig. 30

a third variant of the connections for the rear evaporator of Fig. 26,

Fig. 31

a view of the connections of a third variant of a rear evaporator with a width of twelve flat tubes,

Fig. 32

a plan view of the baffle of the rear evaporator of Fig. 31 with indicated by arrows flow,

Fig. 33

a view of the connections of a variant of a rear evaporator with a width of ten flat tubes,

Fig. 34

a plan view of the baffle of the rear evaporator of Fig. 33 with flow indicated by arrows,

Fig. 35

a variant of the connections for the rear evaporator of Fig. 33,

Fig. 36

a plan view of the baffle of a rear evaporator with a width of eight flat tubes with flow indicated by arrows,

Fig. 37

a top view of the baffle of a rear evaporator with a width of eight flat tubes with indicated by arrows flow path according to a connection variant with respect to the rear evaporator of Fig. 36,

Fig. 38

a view of the connections of a variant of a rear evaporator with twelve flat tubes, in which the two strands are of different lengths,

Fig. 39

a top view of the baffle of the rear evaporator of Fig. 38,

Fig. 40

another variant of the connections for the rear evaporator,

Fig. 41

40 corresponding variant of the connections for the rear evaporator with reverse flow direction,

Fig. 42

another variant of the connections for the rear evaporator,

Fig. 43

a view of a vehicle floor in the region of the arrangement of a heat exchanger from below with a detailed view of a partial area,

Fig. 44

a section through Figure 43 along line AA with a detailed view of a portion,

Fig. 45

a front view of the heat exchanger and flange in the direction of arrow III of Fig. 47,

Fig. 46

a view of the heat exchanger with flange in the direction of arrow IV of Fig. 45,

Fig. 47

a side view of the heat exchanger with flange in the direction of arrow V of Fig.45,

Fig. 48

a section along line VI-VI of Fig. 46,

Fig. 49

a perspective view of the flange to illustrate the connections,

Fig. 50

a perspective view of the flange from the opposite direction,

51

a perspective view of the patch on the bottom plate flange,

Fig. 52

a partial section through the flange, the distributor plate, the baffle and the bottom plate in the longitudinal direction of the heat exchanger,

Fig. 53

a perspective view of the baffle,

Fig. 54

a detailed view of a section of the baffle of Fig. 53,

Fig. 55

a perspective view of the bottom plate, and

Fig. 56

a perspective view of the distributor plate.

A heat exchanger 1, in this case a rear evaporator of a motor vehicle, which is connected via an injection pipe 2 and a suction pipe 3 with an expansion element 4, according to the present embodiment, a collecting box 5 and a plurality of double-row arranged, U-shaped flat tubes 6. The collecting box 5 has a distributor plate 7, each with an opening 8 with slightly outwardly projecting to the outside Edge 9 for the injection and suction of the refrigerant by means of the injection tube 2 and the suction tube 3, a deflector 10 soldered to the distributor plate 7 and a soldered to the baffle plate 10 bottom plate 11 with a plurality of slot-shaped openings 12, in which the ends the flat tubes 6 are inserted.

The injection tube 2 is closed at its end with a closure cap 13. The refrigerant outlet from the injection tube 2 into the heat exchanger 1 is provided in the form of exactly one bore 14, which is arranged in the joining seam of the tube and has a bore diameter which is smaller than the inner diameter of the injection tube 2 (see Fig .. 8). The bore 14 is arranged in alignment with the corresponding opening 10 in the distributor plate 7.

The suction pipe 3 is formed corresponding to the injection pipe 2 and arranged with respect to the distributor plate 7, but the bore 14 at the end of the suction pipe 3 has a bore diameter corresponding to the inner diameter of the suction pipe 3 (see Fig. 13).

The injection tube 2 as well as the suction tube 3 are presently connected directly to the distributor plate 7, for which the respective slightly outwardly projecting edge 9 of the openings 8 in the distributor plate 7 projects into the corresponding bore 14 in the respective tube. Here, the height of the edge corresponds approximately to the pipe wall thickness.

Alternatively, the tubes can also be introduced into the distributor plate with their ends or can be provided a multi-part embodiment, in which case the firmly connected to the distributor plate or possibly also integrally formed part in terms of its function as a part of the injection tube or Suction tube is called.

In the following, the baffle 10 will be explained in more detail. The function of the baffle 10 is primarily the deflection of the effluent from a flat tube 6 refrigerant to the adjacent flat tube 6, wherein the refrigerant is to be mixed in addition, so that a uniform temperature profile is possible. However, this would also be another embodiment of the openings 15, in particular that of the openings 15, which only the deflection of a flat tube 6 to the adjacent flat tube 6 and possibly also serve the discharge of the last two flow-through flat tubes 6 in the suction tube 3, possible. However, due to the strength required by the high pressures, an H-shaped configuration is particularly advantageous.

At both longitudinal ends of the baffle 10, an elongated hole 16 is provided, which extends in length over both rows of H-shaped openings 15 and conducts the refrigerant from one row to the other row (see FIG. 16).

The H-shaped configuration of an injection distributor opening 15a, which is arranged opposite to the refrigerant outlet of the distributor plate 7, corresponds in the present case exactly to that of the other openings 15, whereby exactly this embodiment is particularly advantageous with regard to a uniform distribution of the refrigerant to the two strands. In the present case, the discharge opening 15b of the deflection plate 10, which is opposite the refrigerant outlet of the distributor plate 7, is likewise designed accordingly.

The H-shape of the apertures 15, 15a and 15b has rounded edges in all regions, the ends of the legs being provided with outwardly projecting fillets so that the leg width is somewhat increased at the ends (see Fig. 17). The cross connection has the same Width as the thighs up. The leg width corresponds approximately to the width of the opening of the flat tubes 6, the leg length is formed accordingly.

The present rear evaporator has, as is common practice, compared to conventional evaporators, as used for front-side motor vehicle air conditioners, reduced dimensions. While conventional front evaporator dimensions are in the range of 180 mm to 310 mm for the width, 180 mm to 260 mm for the height, and 40 mm to 50 mm for the depth, the present evaporator has a width of 130 mm and a height of 130 mm at a depth of 40 mm. However, all values in the range of 100 mm to 160 mm, in particular 110 mm to 150 mm, especially 120 mm to 140 mm for height and / or width of the rear evaporator are particularly favorable.

Figures 21 and 22 show a variant of a double row rear evaporator having twelve tubes in width. Here, the Käftemittelzu- and removal takes place in parallel in the longitudinal direction of the collecting tank in the middle thereof (see Fig. 22). The refrigerant flow is evenly distributed in both directions after the injection due to the symmetrical configuration (mirror image embodiment with respect to the central transverse axis of the heat exchanger) of the injection manifold opening 15a, so that there is a relatively uniform temperature profile.

Figures 23, 24 and 25 show another arrangement of the injection and suction pipe, namely in Fig. 23 is a parallel arrangement in which the flow direction in the two tubes is the same, in Fig. 24 a lateral arrangement, in which both tubes are relatively short before the connection to the rear evaporator have a kink (45 ° bend), and in Fig. 25 is a lateral arrangement in which a tube is straight and the other tube provided with a kink. The basic structure of the collecting tank however, including the injection manifold opening 15a is identical to that shown in FIG.

Figures 26 and 27 show a second variant of a double-row rear evaporator having twelve tubes in width. Here, the refrigerant supply and discharge takes place diagonally offset, in each case at the laterally outermost H-shaped opening. The refrigerant flow is in turn distributed evenly on both strands, wherein the strand downstream in the air flow direction, the corresponding series of flat tubes flows through and the other part flow is deflected after flowing through the corresponding side most rear flat tube in the depth direction of the rear evaporator and then flows through the front row until it reaches the last H-shaped opening passes to the suction pipe. The injection and the suction pipe can be arranged to extend parallel in the direction of the longitudinal extent of the collecting tank, as shown in FIG. 26. Alternative embodiments are shown in FIGS. 28 to 30. Particularly advantageous in this case is the embodiment according to FIG. 30, according to which the refrigerant supply and removal is provided at different corners of the heat exchanger, and in which one of the two tubes, in this case the suction pipe, is arranged parallel to and adjacent to the collection box of the heat exchanger ,

FIGS. 31 and 32 show a second variant of a double-row rear evaporator with twelve tubes in width, in which the injection distributor opening lies between those of the two variants described above. The connection is designed according to the variant described above. Other connection possibilities correspond to those of FIGS. 28 to 30.

FIGS. 33 and 34 show a variant of a double-row rear evaporator with ten tubes in the width, in FIG. 35 a connection variant for connection of Fig. 33, but also other arrangement of the injection and suction pipes is possible, in particular as shown in Figures 23-25. Of course, a further apart inlet and outlet of the refrigerant is possible, that is offset with respect to the illustration of Fig. 34 by a respective H-shaped opening 15 to the right or to the left.

FIGS. 36 and 37 also show two variants of the refrigerant supply and discharge for a double-row rear evaporator with eight tubes each in width. The arrangement of the injection and suction pipes may be formed according to the previous variants.

Figures 38 and 39 show a variant of a rear evaporator with different path length of the two strands. A different path length of the two strands may be useful in an unequal distribution of air flow through the rear evaporator to optimize the temperature profile.

As can be seen from all the variants described above, the injection distributor opening 15a is preferably arranged in the second (or the rearmost) row when viewed in the air flow direction, but the outlet opening 15b is arranged in the first row. This enables optimization of the cooling capacity.

The heat exchanger according to the embodiment described above is at operating pressures of 90 bar here, but at least 50 bar, designed (test pressure in this case 160 bar), so that in particular R744, ie CO ₂ , can be used as a refrigerant.

FIG. 40 shows a particularly advantageous variant of the arrangement of the connections for a rear evaporator, the injection and suction pipe being apart from an end region of the injection pipe in which one of the two tubes at the end is slightly bent to allow connection at the same height - are arranged parallel to each other. The tubes are substantially parallel to the direction of air flow, wherein the connection points are arranged centrally on the rear evaporator. This embodiment is particularly advantageous with regard to the temperature distribution over the rear evaporator.

Fig. 41 shows a variant which substantially corresponds to the embodiment of Fig. 40, but the flow direction of the refrigerant is reversed, so that injection and suction pipe are reversed. The dimensions of injection and suction pipe are not shown to scale in the figures.

According to the illustration of FIG. 42, in turn, the connection points are arranged centrally with respect to the rear evaporator, but in the present case only the injection tube is aligned parallel to the air flow direction. The suction pipe runs perpendicular to this and is bent only laterally of the rear evaporator.

Any other arrangements of the injection and suction pipes are possible, but a (possible) central arrangement of the connection points in terms of a uniform temperature distribution is advantageous.

In the following, a special arrangement of a heat exchanger 1 according to the invention will be explained in more detail with reference to FIGS. 43 et seq.

A in a non-illustrated refrigerant circuit arranged heat exchanger 1, in this case a rear evaporator of a motor vehicle, via a flange 102 and one connected to this flange 102 injection pipe and suction pipe (not shown) with a remote in the Front region arranged expansion element (not shown), according to the present embodiment comprises a collection box formed of sheet metal plates 5 and a plurality of double row arranged U-shaped flat tubes 6, between which corrugated fin packages are arranged, as in Fig. 45 indicated in some areas.

The collecting box 5 has a distributor plate 7, each with an opening 8, which are continued in the flange 102 in the form of two passages 103a and 103b, for the injection (8a) and suction (8b) of the refrigerant by means of the injection or the suction tube a soldered to the distributor plate 7 baffle 10 and a soldered to the baffle plate 10 bottom plate 11 with a plurality of slot-shaped openings 12 into which the ends of the U-shaped flat tubes 6 are inserted and soldered to the same.

The injection tube is fixedly connected at its end to a corresponding opening in the flange 102 by means of a fastening device, not shown in the drawing, formed in a manner known in principle, with a pin and a screw screwed into the flange 102. The suction pipe is formed according to the injection pipe and secured to the flange 102 by a second fastening device, wherein, however, the diameter of the suction pipe, in particular the inner diameter due to the larger volume flow, which must be removed, is greater than that of the injection pipe.

The flange 102 is substantially cuboid. The passage 103a in the flange 102 for the supply of the refrigerant to the heat exchanger 1 is continued from a bore in an obliquely extending on the underside of the flange 102 channel (see Fig. 50), which is closed by the distributor plate 7 and in the region of the opening 8a ends. The channel course is due to the configuration of the Käftemittelzuführung conditionally. The refrigerant is discharged via the trained as a hole with different diameter changes bushing 103b. In principle, with a suitable configuration and arrangement of the injection tube, a simple bore, as for the refrigerant removal (feedthrough 103b), may also be provided for the passage 103a.

In the following, the baffle 10 and its function in the collection box 5 will be explained in more detail. The function of the baffle 10 is primarily the deflection of the effluent from a flat tube 6 refrigerant to the adjacent flat tube 6, wherein the refrigerant is to be mixed in addition, so that a uniform temperature profile is possible. This takes place here within the rows with the aid of the double row arranged H-shaped openings 15 in the baffle 10, wherein the refrigerant through a leg of the H-shaped opening 15 on, through the connecting web and over the second leg of the H-shaped opening 15 flows out again into the adjacent U-shaped flat tube 6. At both longitudinal ends of the baffle 10 each have a slot-like opening 16 is provided, which extends in length over both rows of H-shaped openings 15 and directs the refrigerant from one row to the other row.

In principle, however, would also be another embodiment of the openings 15, in particular that of the openings 15, which serve only the deflection of a flat tube 6 to the adjacent flat tube 6 and possibly also the discharge of the last two flowed through flat tubes 6 in the suction pipe, possible. However, due to the strength required by the high pressures, an H-shaped configuration is particularly advantageous.

The H-shaped configuration of an injection Verteiteröffnung 15 a, which is arranged opposite to the refrigerant outlet of the distributor plate 7, in the present case corresponds exactly to that of the other openings 15, where exactly this embodiment is particularly advantageous with regard to a uniform distribution of the refrigerant to the two strands. In the present case, the discharge opening 15b of the deflection plate 10, which is opposite the refrigerant outlet of the distributor plate 7, is likewise designed accordingly.

The H-shape of the openings 15, 15a and 15b has rounded edges in all areas, with the centrally arranged ends of the legs being provided with outwardly projecting rounded portions, so that the leg width is somewhat enlarged at the ends (see FIG ). The cross-connection has twice the width as the legs. The leg width corresponds approximately to the width of the opening of the flat tubes 6, the leg length is formed accordingly.

The present rear evaporator has, as is common practice, compared to conventional evaporators, as used for front-side motor vehicle air conditioners, reduced dimensions. While conventional front evaporator dimensions range from 180 mm to 310 mm for the width, 180 mm to 260 mm for the height and 40 mm to 50 mm for the depth, the present heat exchanger has a width of 130 mm and a height of 130 mm at a depth of 40 mm. However, all values in the range of 100 mm to 160 mm, in particular 110 mm to 150 mm, especially 120 mm to 140 mm for height and / or width of the rear evaporator are particularly favorable.

As can be seen from FIGS. 43 and 44, the collecting box 5 is arranged at the bottom, so that the flange 102 is positioned below the heat exchanger 1 and the supply and discharge takes place from below or towards the bottom. The heat exchanger 1 is placed directly on the vehicle floor 20, which in the region of the flange 102 has an opening 121 through which the flange 102 projects. The opening 121 is arranged by means of a between the distributor plate 7 and the edge of the vehicle floor 120 Sealing element 122 sealed airtight. Around the opening 121, a rib structure is formed for stiffening.

In the vehicle interior, in which the heat exchanger 1 is arranged, separating the vehicle floor 120 from the environment - in addition to the opening 121 for the flange 102 - a condensate drain 123 is provided, through which the condensate collecting in the heat exchanger 1 can be dissipated down. The condensate drain 123 is formed to well below the flange 102 extending, i. to below the connection level of the injection and suction pipe.

For the manufacture of the heat exchanger 1, the flange 102 is secured to the distributor plate 7 by means of a nub 103c (see Fig. 50) projecting over the underside of the flange 102 and into a mounting aperture 8c provided in the distributor plate 7 (see Figs ) is pressed in, prefixed and, after the baffle plate 10 and the bottom plate 11 caulked with the distributor plate 7 and then the flat tubes 6 are mounted together with corrugated fins packages soldered in the context of soldering the entire heat exchanger 1 in a single soldering. The connection of the pipes and the filling of the refrigerant circuit with refrigerant takes place only during the assembly in the vehicle. Of course, instead of a single nub, which cooperates with a corresponding attachment opening, several nubs and mounting holes may be provided, more preferably three, the nubs in principle also on the distributor plate 7 and the mounting holes on the flange 102 may be arranged or a mixed configuration, ie Nubs on both the flange and on the distributor plate, is possible.

The heat exchanger according to the embodiment described above is at operating pressures of 90 bar here, but at least 50 Bar, designed (test pressure in this case 160 bar), so that in particular R744, ie CO ₂ , can be used as a refrigerant.

Claims (17)

Heat exchanger, in particular rear evaporator for a motor vehicle, which is traversed by refrigerant, characterized in that the inflowing into the heat exchanger refrigerant flow is distributed by a distributor to at least two separate strands, such that there is no mutual mixing of each flowing therein refrigerant partial flow , Heat exchanger, in particular rear evaporator for a motor vehicle, comprising pipes (6) and a collecting box (5) comprising a distributor plate (7), a deflecting plate (8) and a bottom plate (9) in which the tubes (6) are provided with at least one end of their ends, and which can be traversed by refrigerant, characterized in that the collecting box (5) has exactly one opening (8) in the distributor plate (7) through which refrigerant enters the collecting box (5) and directly after which the refrigerant flow is distributed on at least two strands. Heat exchanger according to claim 1 or 2, characterized in that the refrigerant distribution is uniform to exactly two strands. Heat exchanger according to one of the preceding claims, characterized in that an injection distributor opening (15a) is formed in the deflection plate (10). Heat exchanger according to one of the preceding claims, characterized in that at the opening (8) adjoining injection distributor opening (15a) is H-shaped. Heat exchanger according to one of the preceding claims, characterized in that the deflecting plate (10) has a plurality of H-shaped openings (15) for deflecting the flow of refrigerant from one pipe to the adjacent pipe. Heat exchanger according to one of the preceding claims, characterized in that the deflecting plate (10) has an H-shaped refrigerant outlet opening (15b). Heat exchanger according to one of claims 5 to 7, characterized in that the H-shaped opening (15, 15a, 15b) is formed with rounded corners. Heat exchanger according to one of claims 5 to 8, characterized in that the H-shaped opening (15, 15a, 15b) is rounded at its leg ends, wherein widening the width of the leg. Heat exchanger according to one of claims 5 to 9, characterized in that the H-shaped opening (15, 15a, 15b) has a leg width corresponding to the width of the transverse connection between the two legs. Heat exchanger according to one of the preceding claims, characterized in that the heat exchanger is designed in two rows. Heat exchanger according to one of the preceding claims, characterized in that the injection distributor opening - viewed in the flow direction of the heat exchanger through the flowing air - is arranged in the last row of tubes. Heat exchanger according to one of the preceding claims, characterized in that exactly one outlet opening is provided, which - seen in the flow direction of the heat exchanger through the flowing air - is arranged in the first row of tubes. Heat exchanger according to one of the preceding claims, characterized in that the heat exchanger (1) is formed in mirror image to the central transverse axis and / or point-symmetrical to the central axis. Heat exchanger according to one of the preceding claims, characterized in that the injection pipe (2) and / or the suction pipe (3) with the heat exchanger (1) are soldered. Heat exchanger according to one of the preceding claims, characterized in that the connection points of the injection tube (2) and / or the suction tube (3) are connected centrally with respect to the width of the heat exchanger (1) on the same. Heat exchanger arrangement comprising at least one heat exchanger, preferably at least one heat exchanger according to one of claims 1 to 16, the refrigerant of a refrigerant circuit can be flowed through, and lines, via which refrigerant to the heat exchanger (1) can be fed and discharged from the same, wherein the heat exchanger (1) arranged in a by a closed wall (120) from the environment interior, the further refrigerant circuit - apart from in the Heat exchanger (1) extending part - is formed extending outside of the interior space, and the connection points of the lines to the heat exchanger (1) by means of at least one on the Wärmeüberirager (1) fixedly mounted flange (102) in an opening (121) in the Wall (120) is arranged outside the interior.

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