DE4309360A1 - Heater heat exchanger for motor vehicles - Google Patents

Abstract

The invention relates to a heater heat exchanger for motor vehicles, having a bundle of heat exchange tubes 2 which are ribbed in parallel, and having at least one tank (cooling-water reservoir) 6 which has a tube plate (sheet) 8 on which the ends 34 of the tubes at one end of the bundle are respectively gripped on the outside and inside by means of an interference (press, force) fit. Projecting into the free cross-section of the end of the respective tube 2 projecting respectively into the tube plate is an adapter (inserted piece) which is respectively constructed as an element which acts on the behaviour of the flow of the flowing medium in the tube. It is provided according to the invention that at least a portion of all the adapters is respectively constructed as a restricting element and that in the same tank 6 the adapters in the different tubes 2 are constructed in such a way with a different geometry that the pressure loss of the flowing medium in the longitudinal region of the adapters is optimised to a desired pressure loss distribution over the tubes 2 of a bundle which communicate with the tank 6. This distribution alters the flow through the individual tubes 2 of the bundle by comparison with a flow occurring for the same geometry of the adapters 40. <IMAGE>

Description

The invention relates to heating heating Exchanger for motor vehicles according to the preamble of claim 1.

Such a heating heat exchanger for motor vehicles witness is known from EP-A2-0 437 825. That serves each time because of the insert as a guide element, which is based on the flow ver holding the medium flowing in the heating heat exchanger, in space common water with additives, as turbulence-generating Leitele ment acts, in particular to generate a swirl flow. The guide element is of a helical shape Guide surface formed for the flowing medium. A horse development of the flow is counteracted by the fact that in the area of the insert the cross section of the tube is widened.

Another known heating heat exchanger for Motor vehicles according to US-A-4 739 828 realize the Merk male of the preamble of claim 1, but with the following Name: With this known heating heat exchanger is not thought of the insert as one each on the stream behavior of the flowing medium in the tube training. The insert is with a cross strut provided with an oval or flat pipe cross-section are provided for internal stiffening. A throttling out The effect of these stiffeners is also a cross countered expansion of the pipe.

In general, it was previously considered undesirable see the clear cross section of the confluence of the pipes Pipe bottom of a water box of a heating heat exchanger for Throttle motor vehicles because of any such pressure loss  inevitably output of the circulation pump for the flowing medium in the heating heat exchanger costs.

Now there are designs of heating heat exchangers for motor vehicles in which the connection geometry to the What serkästen, especially on the water inlet side, secondary but also on the water discharge side, to a different Water exposure to the individual tubes of the tube bundle leads. The main causes of such unevenness are Both of the following: On the one hand, there is always an un uniform water supply if the flow resistance in Water box is comparable to or even larger than the stream resistance in the tube bundle. On the other hand, there is also one Dependence on the rate of entry into the Wasserka most. If the entry speed is low, there is rather one Tendency to preferential water exposure of the one let near pipes while at a high inlet speed there are back pressure phenomena at the opposite of the inlet leads the wall areas of the water tank, with the result that then more water at the inlet distant pipes.

The conditions at known are particularly critical geometries in which this flows in the heating heat exchanger water along the direction of flow as external heat exchange medium serving air and if necessary also is rejected. This applies, for example, to such Types of heating heat exchangers for motor vehicles, de NEN a single inlet connection in the middle of an inlet side Water box is arranged and possibly the drainage egg water box for different air conditioning of vehicles rer and passenger halves in the motor vehicle in two departments is divided, which are each provided with a drain connection. Similar phenomena would also arise if on there is no cross-division in the driver and passenger side is. In both cases, it is common for vertical Arrangement of the tube bundle inlet a lower water tank to constantly use a displacement effect of air  blow by transport from bottom to top. In In this case, all tubes of the tube bundle are formed in parallel tet, so that the pressure loss in the tube bundle is relatively low and comparable to the pressure loss in the inlet side (and also in the drain) water tank.

In such heating heat exchangers for motor vehicles Witnesses have had some expensive items in recent years efforts made for an even water flow all pipes in the tube bundle.

In the known design of a heating heat exchanger with only one central inlet connection on the lower inlet side Water box and a separate air conditioning for driver and passenger side of the motor vehicle parked department Separation of the drain-side upper water tank is only possible in the entry-side, i.e. lower, water tank an additional Distribution plate inserted, which is the amount of water per unit of time the pipes of the tube bundle close to the inlet to the amount of water per unit of time of the pipes of the pipe remote from the inlet connection to align bundle. However, this adjustment takes place an inherently undesirable pressure loss already on the zu Buy pipe connection near pipes of the pipe bundle.

The cost of manufacturing and assembling one Spreading sheets are on the order of 3% of the product cost of the entire heating heat exchanger. That is a yes quite a serious share of the cost, considering that Hei heat exchanger for motor vehicles the character of masses articles, at least of large series articles. So egg ne only type of such a heat exchanger for a only model of a motor vehicle of only one manufacturer piece numbers of more than 100,000 annually. At the in face of the recession in motor vehicle construction particularly strong Competition between automotive suppliers is therefore an issue 3% of the total costs are extremely high.

The invention has for its object an al alternative way of solving the problems mentioned unevenly internal water supply to the individual pipes of a hot  specify heat exchanger for motor vehicles, which indicates is less expensive and also creates the opportunity even with types of heating heat exchangers for motor vehicles testify to the discussed, particularly problematic type the what Reduce the supply of water per unit of time only where there is no additional measures come to an excess supply of water could. As already mentioned, the latter is for example in the case of backflow apparently the case.

This task is done with a heating heat exchanger with the features of the preamble of claim 1 by it characteristic features solved.

The cost saving given by the invention is mainly based on the fact that the distribution measures for the individual tubes of the tube bundle impinging water on one Component made that anyway for the heating heat exchanger must be formed. That makes it possible to do so far Distribution sheet used in the difficult designs mentioned and to completely waive its manufacturing and assembly costs It is now deliberately throttling the free pipe cross-section in the area of the tube sheet of the respective Wasserka contrary to all previous thinking. Reason In addition, it is even possible to use all the tubes in the tube bundle throttling, even if only in a relatively small amount Dimensions depending on the available delivery rate the circulation pump of the internal heat exchange medium of the heating metauschers. However, even such a drape is preferred only in selected tubes of the tube bundle if otherwise unused throttles the remaining free cross section of the other pipes of the Tube bundle made, and then with the aim of such Pipes that get enough water from the start without to take additional measures with water and only such pipes, which otherwise supply an excessive amount of water be throttling in the water supply.

The measure according to the invention for water distribution the individual tubes of the tube bundle have a cost effect only in the slightly larger material consumption  for the throttling or free cross section in the area of Tube bottom constricting training of each at all throttling insert, and additional Mon daily costs do not occur at all. When shaping can NEN the forms used so far are used; one can namely the throttle formation in the area of the mold parting plane so that there are no increased tool costs Because of the far greater variability and the poss ability, several tubes of the tube bundle without any additional measures to leave me, results for those provided according to the invention Distribution measures cost savings in size Order of even two orders of magnitude compared to the manufacturer costs of assembly and installation of the conventional additional Ver partial sheet.

The design of a heating heat according to the invention exchanger to an optimized target pressure loss distribution appropriately obtained experimentally. One goes as a reference expedient from such an interpretation, in which the Insert pieces protrude into pipe sections, just like the State of the art have expanded somewhat, so that this Geometry no or only a certain low pressure ver lust arises. It is not essential that To achieve the target pressure loss distribution exactly, since there is already one Approximation to the ideal conception fulfills the target conception, the different tubes of the bundle are reasonably even with water and for this measure if possible little material and assembly effort to operate.

The invention is primarily for the known Distribution plate underlying target has been developed to all pipes be even or at least even with water open (claim 2). Gera offers this solution de advantages even if you go from the lower part of the Hei heating air for the foot area and from the upper Area of the heating heat exchanger hot air for the head area in the vehicle. Then it does not come as before uneven loading of the tubes of the tube bundle, the  from the inlet-side lower water box to the outlet-side top ren water box run vertically, to a temperature distribution development with penetration of a hot zone up to the upper part rich of the radiator in the central zone of the bundle. Derar certainty is reliably avoided by the equalization, even if there is not exactly the same pipe loading.

But you can also wear one for other reasons aim for or set the desired pressure loss distribution in order to certain areas of the heat exchanger deliberately with more water quantity per unit of time to load a larger one To generate heat output. An example would be an increased heat power generation in the peripheral areas of the heat exchanger. On Proverb 3 offers one possibility.

Claims 4 and 5 relate to two preferred types Use cases for the invention in known constructions of water boxes. So claim 4 relates to the known case that the insert is already an integral part of the Rohrbo dens of the water box is (US-A-4 739 828). Claim 5 be meets the case of EP-A2-0 437 825 from which the invention is based goes. In this known water tank is a base plate the water box with a separately manufactured component for Tube bottom of the water tank united. The separately made Component comprises various sleeve parts that are in openings of the Bottom part of the water box including the pipe ends can be pressed with a press fit and by each other ver a web structure to a single prefabricated component is one.

In both known cases, the invention can be used either in the manufacture of the integral tube sheet or in the production of the separate component from the outset at Gaining shape without additional work steps required are.

The execution of the Erfin is particularly convenient dung when the inserts on a made of sprayable art fabric existing component of the water tank are formed, what in the known cases of an integral tube sheet or  of a separate component is already state of the art. The invention also makes it possible, in itself the design of EP-A2-0 437 825 already known aspects, that the inserts as turbulence-generating guide elements, and specifically shaped to produce a swirl flow are, with the design according to the invention as throttle elements to combine.

There is a structurally particularly simple way to do this Claim 9. Building on the well-known embodiment of the Insert pieces as sleeve parts engaging in the pipe end can then the throttling elements from over the circumference of the sleeve Partially distributed and inwardly projecting extensions form. Here, a normal pinhole is turned into individual ones the scope of distributed and outside segments dissolved. This has in addition to a very simple adjustment of the throttle wire kung, which is comparable to that of a normal orifice is the advantage that the throttle element is not an internal Ver stiffness of the insert acts and influences the Ver compression of the pipe ends in one or more parts Tube sheet could have.

In the invention, it is possible, as in the case of known distribution plate, the distribution measures only on one Provide water tank, in which case, in particular, but not exclusively, the inlet-side water tank comes into question. According to claim 10 you can optimize to a target pressure loss distribution also at both ends of the bundle of Provide pipes. The first advantage is that the Flow constricting cross section at the individual water tank ge can keep wrestlers and counteract any blockages can. It is also constructively advantageous by simply according to claim 11 the same constructive measures on both sides provided water boxes.

Claims 12 to 14 select some known per se te designs of heating heat exchangers with at both ends of the Pipe bundle provided water boxes, where measures are useful for flow equalization and therefore  the effect achieved by the invention is particularly clear is.

However, the invention is not only in Hei heat exchanger for motor vehicles with water on both sides boxes limited; the invention particularly also includes sol che heat exchangers, in which a single divided Water box is provided, both the water inlet and also contains the water outlet and possibly still in white tere chambers, e.g. B. for different control of the warm air feed to the driver and passenger side, is designed. In sol Chen cases then the tube bundle consist of U-shaped bent Pipes in which the inlet opening and the outlet opening ne are next to each other and on the same, but under different sections of the same water tank.

The invention will now be described more schematically Drawings on several embodiments explained in more detail tert. Show it:

Figure 1 shows a heating heat exchanger for motor vehicles GE in perspective, partially cutaway view.

. Fig. 2a and 2b two views in air flow direction and perpendicular to a different design of a heating heat exchanger for motor vehicles;

FIGS. 3a and 3b Fig another design of a wetting Hei heat exchanger for motor vehicles in air flow direction and perpendicular thereto.

Figure 4 is a partial section through a first type egg NES tube sheet through the tube axis.

Figure 5 is a partial section through a second type of tube sheet through the tube axis.

FIG. 6 is a plan view of a separately manufactured component which, in the design according to FIG. 5, forms the tube sheet together with a base plate of the water tank; and

Fig. 7 is a plan view in the axial direction of a tube on an insert that can be used both in the construction according to FIG. 4 and in the construction according to FIG . B. as a ver enlarged and more detailed drawing of a partial view of FIG. 6 in the construction of FIG. 5th

Referring to Figs. 1 to 3b of generality are shown exchangers three per se known designs of Heizungswär without limitation, where the application of the underlying idea of the invention is particularly effective.

All three indicated by the number of the figures NEN are heating heat exchangers for motor vehicles with a bundle of parallel ribbed heat exchange tubes 2 , the ribbing 4 is only indicated. The tubes are made of metal, preferably aluminum or an aluminum alloy, such as in particular AlMn1. The ribbing suitably consists of lamella packs in which the individual lamellae have len receiving sleeves, into which the tubes are positively expanded. The ribbing 4 is expediently selected from the same metal as the tubes 2 . For special cases, however, the pipes and / or the fins could also be produced from other materials, possibly also from a plastic.

In the case of the tube bundles with U-shaped tubes 2 , a single water tank 6 is sufficient. In the two embodiments according to FIG. 1 on the one hand and according to FIGS . 3a and 3b on the other hand, the adjacent ends of the U-shaped tubes arranged parallel to one another open into a common tube sheet 8 of a single water tank 6 , which is separated by a partition wall 18 into an inlet side first Department 10 and ei ne second side department 12 is divided.

In the embodiment according to FIG. 1, this subdivision of the water tank 6 takes place through such a partition wall 18 which is oriented transversely to the air direction 20 of the incoming air and thus acts as a longitudinal division of the water tank 6 .

The inlet-side connection 14 and the outlet-side connection 16 are oriented along the flow direction 20 of the incoming air, but directed against the air flow according to the water flow direction 22 . Both connections 14 and 16 are arranged on the corresponding departments 10 and 12 with tig and thus axially aligned. The dividing wall 18 bil det a baffle for the water flowing through the connection 14 , which is then distributed transversely to the flow direction 20 of the air or inflow direction 22 of the water in the department 10 and collected again in the department 12 towards the connection 16 .

The third embodiment according to FIGS . 3a and 3b does not differ from the embodiment according to FIG. 1 with regard to the type and flow type of the outside air except for the following special feature.

The only difference is that the connection 10 on the upstream side and the outlet side connection 12 are oriented parallel to one another in the longitudinal direction of the two sections 10 and 12 and thus at right angles to the direction of flow 20 of the incoming air. In this case, the water to be run is not dammed up early on the partition 18 , but is distributed over the entire length of the water tank and then only runs against the opposite end wall of the water tank. The same applies with the reverse direction of water flow in the outlet-side section 12 .

In the embodiment of Fig. 1, the inflowing water accumulates in almost all practical applications in the areas which are located in the vicinity of the supply 14 side connection 14 , so that the pipes connected there are supplied with a larger amount of heating water than the distant supply connection Tube.

In the embodiment according to FIG. 3, the inflow-side water supply of the individual pipes 2 depends rather on the flow rate of the inflowing water. At low flow velocity, there is more of an oversupply of the pipes near the inlet-side connection, at high flow velocity, which still leads to congestion on the narrow side of the water tank facing away from the inlet, rather at the end of the water tank facing away from the inlet or from its inlet side Department 10 .

The second embodiment according to FIGS. 2a and 2b relates to a particularly critical heating heat exchanger for motor vehicles with respect to the flow distribution, in which the tubes 2 are arranged in a straight line parallel to one another and are connected in parallel. This leads on the one hand to the fact that a feed-side water tank 6 a and a drain-side water tank 6 b must be provided separately from one another. On the other hand, in contrast to the first and third embodiments described above, no U-shaped elbow sections 24 are provided, which in themselves cause a relatively high pressure loss. When connecting straight pipes in parallel, it is therefore particularly easy to achieve comparable pressure losses in the pipes 2 and in the water tanks 6 a and 6 b.

The inlet-side water tank 6 a consists of a single section with an inlet connection 14 , which is arranged centrally on the water tank 6 a along the flow direction 20 of the incoming air, but in the opposite direction.

The drain-side water tank 6 b is divided into two parts by two partitions by means of an intermediate wall 26 . Since two departments 28 and 30 are separated from one another on the outlet side in the water box 6 b, which are provided for separate heat supply for the driver side and front passenger side of the motor vehicle. Each of these two departments 28 and 30 each has a drain-side connection 16 a and 16 b, which are arranged near the intermediate wall 26 . The two connections 16 a and 16 b are arranged parallel to one another and to the connection 14 , with the water outflow direction being oriented parallel and in the direction 20 of the incoming air.

As shown schematically, the two connections 16 a and 16 b each have a control valve 32 a and 32 b downstream in terms of flow with respect to the heating water. With means of the two control valves 32 a and 32 b, you can then independently control the heat supply to the driver's side and the passenger's side of the motor vehicle.

The following are also of particular interest Variants not shown in the drawing:

For example, in the second embodiment, the subdivision of the drain-side water tank 6 b by the intermediate wall 26 can be omitted. Then a single ablaufsei term connection 16 is sufficient, which is then expediently arranged in parallel to the inlet side term 14 in the middle of the water tank 6 b. The statements about the water flow direction remain unchanged. In this case, the control options by means of valves 32 a and 32 b are eliminated. It is sufficient here, as with all such heating heat exchangers for motor vehicles, in which no particular spatial division into individual sections of the motor vehicle, such as the driver's side and passenger's side, is provided, a single control valve, not shown, which, as in the second embodiment of FIGS. 2a and 2b drain side is usually switched.

However, an inlet-side circuit also comes into play Question.

Conversely, one could also in a manner not shown, also the embodiment of FIG. 1 in modifizie reindeer, characterized in that the drain-side compartment 12 as well as the off-running side water box 6 b of the second embodiment into two compartments by an unshown partition subdivided and then as in the second embodiment with the arrangement of two drain-side connections 16 a and 16 b in the vicinity of the central partition, the separate control valves from the run side. In this case, the only water tank 6 of the single type would disintegrate into a total of three departments, namely the input-side department 10 and two output-side departments by dividing the department 12 of the type according to FIG. 1 in the middle.

In all of the described and other known designs of heating heat exchangers for motor vehicles, the following two types of training of the tube sheet of the respective water tank are particularly in question, without restricting the generality, as they are illustrated above all by the alternative construction of FIGS. 4 and 5.

In the design of FIG. 4 an integrally gefer-saturated tube plate 8 is provided, which suitably is a mold piece of polyamide with about 30% glass fiber.

The end of the respective tube 2 projecting from the tube 34 projecting with the ribbing 4 is mechanically expanded and held in the tube sheet 8 with a press fit. For this purpose, a sleeve 38 protrudes from a plate-shaped part 36 of the tube sheet 8 in the direction of the respective tube, which comprises the tube end 34 fluid-tight on the outside. In addition, a likewise hülsenför shaped insert 40 engages in the pipe end 34 and is liquid-tight on the inner surface of the sen. The insert 40 , like the sleeve 38, is made integrally with the tube sheet 8 . Sleeve 38 and insert 40 are so connected to the plattenför shaped part 36 of the tube sheet 8 that an annular gap 42 is formed in which the expanded tube end 34 engages with a press fit on both sides. Although here the insert part has a slightly smaller clear cross section than the unexpanded tube 2 , there is practically no flow restriction in comparison to the unexpanded tube 2 because of the nozzle-shaped inlet opening 44 in the clear cross section of the insert part 40 .

According to the second design according to Fig. 5 of the Rohrbo is composed to 8 of two components, namely the one hand, of a base plate 46 of the water tank and on the other hand, egg nem separately fabricated member 48. At least component 48 is expediently made of sprayable polyamide with about 30% glass fiber. The base plate 46 can be made of the same material, but need not be. In addition to other types of plastic and plastic compositions, a metallic education could even be considered.

Instead of the one-sided sleeve 38 , a sleeve 50 projecting on both sides of the base plate 46 is formed here. In a manner not shown, one could also provide a corresponding double-sided sleeve in the embodiment from FIG. 4 or in the embodiment according to FIG. 5 only choose a one-sided sleeve according to FIG. 4.

The pipe end 34 here has a first widened section 52 and a section 54 located at the end of the pipe and widened yet again. Here, as in the case of FIG. 4, the pipe end 34 is arranged axially outside the normal area of the pipes provided with the ribbing 4 , where the pipes have been mechanically expanded in an undetectable manner against the fin ribbing 4 (both in FIG. 4 and in FIG Fig. 5).

In the embodiment of Fig. 5, the sleeve 50 is now an integral part of the base plate 40 while the flat case formed as a sleeve part insert 40 integral Be is stable in part of the particular member 48. The first expanded section 52 of the tube end 34 is held between the sleeve 50 and the sleeve-shaped insert 40 with an interference fit. The further widened end section 54 of the pipe end 34 engages in an annular gap 56 which is formed in the component 48 . This component 48 also has a collar 58 which engages in an annular groove 60 on the end face of the sleeve 50 facing the inside of the water tank. The component 48 is pressed with the collar 58 into the annular groove 60 during assembly on the base plate 46 to the finished tube sheet 8 . This engages from section 54 of the pipe end in the undersize ring gap 56 and is pressed into this. The additional widening of the pipe end 54 is already roughly pre-shaped and finds its final configuration during pressing.

From Fig. 6 it follows that in the mounting manner according to Fig. 5, the individual inserts 40 for all pipes 2 integral components of a single separate component 48 , which is united via connecting webs 62 . A continuous plate could also be provided in the component 48 with a greater consumption of material, but this is less an option for reasons of material savings.

Both the in connection with Fig. 4 as well as in the in connection with Fig. Constructions described 5 and generally, is now provided that the respective insert piece has at least in some pipe connections in the tube sheet with an additional choke member 64 is provided. The facultative attachment possibility of the throttle element is particularly highlighted in Fig. 4 by dashed lines. The same applies to the embodiment of FIG. 5, but where the throttle element is shown as a full cross section.

In both cases, the throttle element 64 is of the type formed as a pinhole, which is arranged only on a partial area of the axial length of the insert 40 . In the design of FIG. 4, the arrangement is nikationsöffnung here at the Kommu 66 of the pipe 2 with the inside of the water box arranged, namely even flush with the inside of the tube bottom 36. In the embodiment according to FIG. 5, the throttle element is instead arranged approximately at half the axial length of the insert 40 .

These arrangement options could also be exchanged in both embodiments of FIGS. 4 and 5.

In the construction shown, they are due to the shape of the mold, in order not to have to carry out any additional shaping and demolding work within the meaning of the objective of the invention. It can be seen from the tapering demolding curves ending in the area of the Drosselele element 64 that in both cases the throttle element can be obtained in the region of the parting plane from two injection molds.

The axial length of the insert 40 is expediently about the diameter of the tube 34 after the first or, if appropriate, the only expansion in all types. The orifice plate forming the throttle element need only have a sol che wall thickness, as is required in terms of shape, z. B. in plastic molding in particular 0.4 to 0.8 mm thickness.

The degree of constriction by the pinhole in relation to the sleeve part of the insert 40 depends on the optimization according to the invention. Throttling in the range between 10 and 90% of the unthrottled free cross-section of the sleeve part of the insert 40 is definitely possible. The exact dimensions depend on the application conditions obtained through experiments.

The throttle diaphragm 68 is expediently formed by projections 70 which protrude inwards from the sleeve part which forms the base body of the insert part 40 . The extensions 70 are distributed over the circumference of the sleeve part segment-like with ge mutual spaces 72 and made integrally with the insert 40 . It is alternatively possible to choose the different free cross sections of the throttle element primarily by the free cross section of the central opening 74 or by the width of the intermediate spaces 72 , mixed forms also being possible. An embodiment is preferred in which the extensions all have the same geometry with only narrow gaps in terms of shape and the essential change in the throttle cross section takes place in the area of the central opening 74 .

The spaces 72 then form normal to the inner wall surface of the sleeve part of the insert extending star-shaped slots, which have the sole meaning of preventing any internal stiffening effect of the insert due to the throttle element. The slot width must be chosen so wide that the slots come into contact with the pressing at best, but there is no additional material deformation between the individual segment-shaped extensions 70 .

The invention has been illustrated using round tubes, so that the central aperture 74 is then shown round. This is useful, but not absolutely necessary.

In a manner not shown, the invention can also be used in other cross-sectional configurations of the tubes 2 , in particular in oval tubes and in flat tubes. The outer contours of the insert pieces 40 and the geometric shapes of the throttle elements 64 must then be adapted accordingly.

It is possible to adjust the individual extensions 70 with respect to the axis of the insert 40 in the manner of a rotor blade or a slant so that a swirl flow is generated in the flowing water, which increases the heat transfer in the first region of the subsequent pipe 2 while promoting turbulence. The extensions 70 then have not only throttling character, but also character as interacting guide elements.

In Figs. 1 and 6 is finally indicated in the drawing that the throttle cross section is selected to be different at the individual tubes 2 in the framework of the invention. Dement speaking accordingly in the arrangement of FIG. 1 in the area of the two connections 14 and 16 each have a greater throttling than shown in the adjacent areas and in the end regions of the departments 10 and 12 of the water tank 6 a throttle free cross section can be seen.

Similarly, one can see in the top view of FIG. 6 the central region of the component 48 with greater throttling.

Without restricting the generality, only two-row designs are shown for the designs of heating heat exchangers shown in detail. However, that more than two-row designs come into question can be seen in the Dar position according to FIG. 6, which is related to a four-row heat exchanger with mutually offset tubes.

An arrangement of the throttle cross sections is preferred, which is largely the same in the individual rows if you apart from differences due to possible pipe misalignment. It the throttle cross-section along the individual rows is then more likely hen varies.

Claims (14)

1.Heater heat exchanger for motor vehicles with an at least two-row bundle of parallel ribbed heat exchange tubes ( 2 ), in particular made of metal, and with at least one water tank ( 6 ) which has a tube sheet ( 8 ), in particular made of plastic, on which the ends ( 34 ) of the tubes at one end of the bundle are each outside and inside with a press fit to, with an insert piece ( 40 ) protruding into the free cross section of the end of the respective tube ( 2 ) projecting into the tube sheet, each as one on the Flow behavior of the flowing medium in the tube acting element is formed,
characterized,
that at least a part of all insert pieces ( 40 ) is designed as a throttle element ( 64 ), and
that in the same water box ( 6 ) the inserts ( 40 ) in the different pipes ( 2 ) are formed with different geometry so that the pressure loss of the flowing medium in the length range of the inserts ( 40 ) to a target pressure loss distribution over the with Water box ( 6 ) communicating tubes ( 2 ) of the bundle is optimized, which changes the flow through the individual tubes ( 2 ) of the bundle compared to a flow with the same geometry of the insert pieces ( 40 ). 2. Heating heat exchanger according to claim 1, characterized in that the desired pressure loss distribution, the flow through the individual tubes ( 2 ) of the tube bundle ver uniformly, preferably makes the same. 3. Heating heat exchanger according to claim 1, characterized in that the target pressure loss distribution provides a different flow through the tubes ( 2 ) of the bundle transverse to the flow direction ( 20 ) of the air serving as the external heat exchange medium. 4. Heating heat exchanger according to one of claims 1 to 3, characterized in that the insert pieces ( 40 ) are integral components of the tube sheet ( 8 ). 5. Heating heat exchanger according to one of claims 1 to 3, characterized in that the inserts ( 40 ) are parts of a separately manufactured component ( 48 ) which together with a base plate ( 46 ) of the water tank ( 6 ) whose tube sheet ( 8 ) forms. 6. Heating heat exchanger according to one of claims 1 to 5, characterized in that the insert pieces ( 40 ) are formed on a component of the tube sheet ( 8 ) consisting of injectable plastic. 7. Heating heat exchanger according to one of claims 1 to 6, characterized in that the insert pieces ( 40 ) are additionally formed as turbulence-producing guide elements ( 70 ). 8. A heating heat exchanger according to claim 6, characterized in that the insert pieces ( 40 ) have a swirl flow, they are convincingly shaped. 9. Heating heat exchanger according to one of claims 1 to 8, characterized in that the insert ( 40 ) forms an inside of the tube ( 2 ) adjacent sleeve part, from which over the order distributed projections ( 70 ) protrude inwards. 10. Heating heat exchanger according to one of claims 1 to 9, characterized in that the optimization to a target pressure loss distribution is provided at both ends of the bundle of tubes ( 2 ). 11. Heating heat exchanger according to claim 10, each with a water tank ( 6 a, 6 b) at both ends of the bundle, marked net by the same design of the tube sheets ( 8 ) of both water boxes ( 6 a, 6 b) together with their inserts ( 40 ). 12. Heating heat exchanger according to one of claims 1 to 11, characterized in that a single inlet connection ( 14 ) of an inlet-side water tank ( 6 a) is arranged centrally in this along the flow direction of the air ( 20 ) serving as the external heat exchange medium. 13. Heater heat exchanger according to claim 12, characterized in that a single drain connection ( 16 ) from the upstream water tank ( 6 b) is arranged centrally in this along the direction of flow to serve as the external heat exchange medium air ( 20 ). 14, heating heat exchanger according to claim 12, characterized in that two outflow ports (16 a, 16 b) of a drain-side water box (6 b) one on each separated by an intermediate wall (26) section of the water box (16 a, 16 b) along the flow direction of the air ( 20 ) serving as the external heat exchange medium is attached and each provided with a control valve ( 32 a, 32 b).