DE10102640A1 - Heat exchanger, for vehicle cooling systems, uses adjacent water and oil heat exchange channels for an improved heat exchange action - Google Patents

Abstract

The heat exchanger, especially in a cooling system for a vehicle motor or gearbox or power steering, has two end boxes and a network (1) of cooling channels between them. It also has an integrated oil heat exchanger with an oil heat exchange stretch, with at least a part of the cooling network through it where the oil heat exchange channels and the water heat exchange channels (4i-4m) are next to each other, to exchange heat between them. The water heat exchange channels form part of the low temperature zone (21) of the heat exchanger, where they are against the oil heat exchange channels. Valves (31) control the water and oil flows through the low temperature zone.

Description

The invention relates to a heat exchanger, in particular for use in a motor vehicle.

Such heat exchangers, generally referred to as coolers, are widely available Application for deriving a heat flow from a fluid circuit, for example a cooling water or oil circuit of an internal combustion engine, or also from a gearbox or power steering oil circuit, to the ambient air.

DE 195 09 654 A1 describes a heat exchanger unit with a uniform one Cooling network is known which via end boxes in a cooling medium circuit is involved. The end boxes are divided. This will make it possible to separate cooling circuits via the uniform cooling network to lead.

DE 197 57 805 A1 discloses a heat exchanger for a motor vehicle which is a cooling network provided for a single cooling water circuit is arranged between two end boxes, being in one of these two end boxes a tube bundle is inserted over which an engine oil circuit is guided.

From DE 100 14 484 A1 a heat exchanger is known which also has a has an end or collecting box integrated oil cooler.

The previously described two media channels Heat exchangers prove to be a space saving also with a view to reducing the assembly effort as special advantageous.

The invention has for its object a heat exchanger with two separate cooling media paths to create, which is characterized by an improved Characterized heat transfer behavior.

This object is achieved with a heat exchanger a first end box, a second end box, a cooling network, the cooling box has channels that extend between the two end boxes and one Oil heat exchanger device with an oil heat exchange path, the oil Heat exchange path runs through at least a section of the cooling network, and in this cooling network section oil heat exchange channels and water Heat exchange channels are arranged adjacent to each other for the transmission of a Heat flows between at least one oil heat exchange channel and one neighboring water heat exchange duct in the area of the cooling network.

This makes it possible in an advantageous manner for the respective company stood a motor vehicle cheapest return temperatures of the separate To achieve fluids with significantly reduced delay times. It will in particular possible to close the cold start operating phase of a drive system shorten and thereby a reduction in emissions and an increase to achieve the life of the system.

According to a particularly preferred embodiment of the invention Heat exchanger including its end boxes made of a metal material, preferably made of aluminum. In addition to a particularly robust, pressure-stable and advantageous in terms of heat transfer behavior Design also achieved a low total weight.

The adjacent heat exchange channels are advantageously above each just a wall as thin as possible, made of a metal material separated from each other. This creates a particularly effective heat transfer reached between the two heat exchange channels. The heat exchange channels have preferably on the respective volume flow and on the pressure of the through the medium. It is possible for the oil Heat exchange channels to provide cross-sections similar to circular surfaces.  For the water heat exchange channels can be preferred because of the here lower cross-section can be selected. The connection of the metallic elements of the heat exchanger are preferably made in the frame a soldering or electrolysis process. Alternatively or in combination With this measure, it is also possible to replace the elements of the cooler Coupling the adhesive or vulcanization process. The between the two adjacent heat exchange channels can be provided with a profile or rib structure to increase the Heat transfer capability. The flow of the neighboring heat exchange channels are preferably based on the counterflow principle.

According to a particularly preferred embodiment of the invention, the the water heat exchange channels adjacent to the oil heat exchange channels are part of a Low temperature range of the heat exchanger. This will turn it on advantageously possible, the temperatures of oil and water on the same Maintain temperature level. In particular, it is reliably achieved that that on the output side the temperature of the oil is not significantly above the temperature of the Cooling water is in the return area.

One with a view to a particularly precise adjustment of the initial temperature Ren of the heat exchanger is advantageous embodiment of the invention given that a valve device is provided for controlling the water and / or oil flow through the common cooling network section. These valves direction advantageously comprises at least one actuator that temperature dependent freely defined passage cross-sections for the water or the oil. The for this purpose, preferably controlled with regard to their passage cross section Fluid path sections can have slide and / or flap devices. These organs can be actuated by actuators using heat the cooling media are activated. Alternatively, it is also possible to use the actuators to be operated electrically or pneumatically in accordance with a control unit.

A particularly space-saving embodiment of the invention is achieved by an end box device of the oil heat exchanger is accommodated in end boxes through which several water heat exchange channels of the cooling water circuit  are summarized. The heat exchanger is preferably a cross-flow heat formed exchanger, with an upper region of the heat in the installation position exchanger forms a high temperature water cooling area and one in installation position on lower area of the heat exchanger an oil / water as well as preferably Oil / water / air heat exchange area forms.

The high temperature water cooling area preferably includes a high temperature ratur water outlet which is controlled with a low temperature water inlet of the oil / water or oil / water / air heat exchanger section is connectable.

As an alternative to the measures described above or in particular advantageously in combination with this, the task specified above according to the invention also solved by a heat exchanger with a first End box, a second end box, a cooling network that has cooling channels extend between the two end boxes and an oil heat exchanger Direction with a first between an oil inlet and an oil outlet kenden oil heat exchange path, the oil heat exchange path a first Has oil flow path that extends through the cooling network, and one Valve device is provided for controlling the oil flow between the Oil inlet and the oil outlet.

This also makes it possible to adjust the initial temperature of the oil in particular quickly to a desired temperature level during a cold start phase to raise and the heat exchanger performance only at a correspondingly high Increase heat input into the oil to the required level and increase the heat dissipate to the environment if necessary.

Advantageously, the valve device is designed such that it Oil flow between the oil inlet and the oil outlet via the first flow controls away. Alternatively - or in combination with it - it is possible, the cooling water inflow to the common heat exchange path in to control the cooling network.  

The second oil flow path is advantageously to the first oil flow path arranged in parallel. This makes it possible via the second oil flow path to provide a bypass over which all or part of the oil flow can be passed between the inlet and outlet of the oil heat exchanger.

Alternatively, or in combination with a bypass to the first Oil flow path, it is possible to use the first oil flow path and the second Arrange oil flow path in series and selectively the two flow paths to couple with each other. This makes it possible to increase the heat exchange capacity, the oil heat exchanger by selectively extending the heat exchange path or by changing the heat exchange behavior thereof in a desired one Way to set. It is also possible to switch the corresponding switching elements selectively in series or parallel in the oil circuit couple. Intermediate stages are also preferably by appropriate Design of a valve device adjustable.

A valve device is preferably provided, which over the first Oil flow path controls flowing oil flow. This valve device comprises preferably an actuator for temperature-dependent adjustment of a Opening cross-section. The actuator can contain an element, for example whose volume changes depending on its temperature.

The valve device is preferably provided in the region of one of the end boxes. The valve device can be attached in such a way that this can be removed non-destructively from the heat exchanger. The valve device device can be arranged in such a way that this to the outside - or to Removal of a connecting hose - exposed or at least for a tool is accessible.

The heat exchanger according to the invention is preferably of all-aluminum construction manufactured. In addition to increased pressure and temperature resistance also a simplified separation of recyclables as part of a recycling process reached.

Further advantageous details of the invention result from the following the description in connection with the drawing. Show it:

Figure 1 is a simplified illustration of a first embodiment of a heat exchanger according to the invention lamellae design having an opening formed within a cooling network oil / water / air heat exchange route.

Figure 2 is a simplified illustration of a second embodiment of a heat exchanger with an integrated control valve for controlling the oil flow in the oil heat exchanger.

Fig. 3 is a simplified representation of a third embodiment of an oil / water / air heat exchanger in which the oil heat exchanger is integrated in a low-temperature area of the cooling network, the water access to the low-temperature area being controllable via the removal flow from the low-temperature area;

Fig. 4 is a simplified representation of a third embodiment of an oil / water / air heat exchanger in which the oil heat exchanger is integrated in a low-temperature area of the cooling network, the water access to the low-temperature area being controllable via a valve device integrated into an end box;

Fig. 5a is a detailed sketch for explaining the structure of an also in lamella construction and inte grated in the low temperature oil heat exchanger;

Fig. 5b is a simplified view of the detail of FIG. 5 from below to explain the staggered transverse channels.

The heat exchanger shown in FIG. 1 comprises a structure, hereinafter referred to as cooling network 1 , which extends between a first water end box 2 and a second water end box 3 . The cooling network 1 includes water heat exchange channels 4 a. , , 4 h. About this water heat exchange channels 4 a. , , For 4 hours, the two water end boxes 2 , 3 are connected to one another in a sealed manner.

The water heat exchange channels 4 a. , , 4 h are made in the present embodiment, for example, from an aluminum material and have a lenticular internal cross section. Between the water heat exchange channels 4 a. , , 4 h cooling fin elements 5 are provided to enlarge the material surface of the cooling network 1 provided for heat transfer to the ambient air. The cooling fin elements 5 are also made of a metal material - preferably an aluminum alloy. In the embodiment shown here, the cooling fin elements 5 are designed as a folded structure.

The first water end box 2 is provided in its upper position in the installation position with a water inlet 6 via which the heated cooling water derived from an internal combustion engine reaches the water end box 2 . The second water end box 3 is provided with a water outlet 7 from which is in the second water end box 3 after flowing through the water heat exchange channels 4 a. , , 4 h collecting water can be drained.

In one, in the installation position of the heat exchanger, the lower area in the cooling network 1, a plurality of oil heat exchange channels 8 a. , , 8 d, integrated. This oil heat exchange channels 8 a. , , 8 d are integrated into an oil circuit via a first oil end box 9 and a second oil end box 10 .

In the embodiment shown here, the two oil end boxes are formed in one piece with the respectively adjacent water end boxes 2 , 3 , with media-tight partition walls 11 , 12 being formed between the adjacent end boxes 2 , 9 and 3 , 10 , respectively. The two oil end boxes are provided with connecting elements for integrating the in cooperation with the oil end boxes 9 , 10 and the oil heat exchange channels 8 a. , , 8 d formed oil heat exchange section 14 in an oil circuit. Deviating from the arrangement of the connection elements of the water end boxes 2 , 3 , the oil end boxes 9 , 10 have an oil inlet 15 in the vertical direction below an oil outlet 16 . This supports an approximation of the oil temperature to the cooling water temperature.

An oil / water heat exchange path 17 is formed in the cooling network 1 , via which a heat transfer between oil and water is made possible. The oil / water heat exchange path 17 comprises at least two heat exchange channels 4 h and 8 a arranged in the immediate vicinity. This makes it possible to heat the oil in the oil circuit via the cooling water within a cold start phase in the area of the cooling network 1 . After the oil contained in the oil circuit has warmed up, this heat exchange section reliably limits the maximum oil temperature.

In the embodiment shown here, the oil / water heat exchange path 17 runs essentially horizontally between the corresponding end boxes 2 , 9 and 3 , 10 at the level of the media-tight partition walls 11 , 12 . Cooling fin elements 5 are also provided between the adjacent oil heat exchange channels 8a 8h. It is possible to provide different duct geometries and different configurations of the cooling fins 5 for the individual areas of the cooling network.

The partition provided in the area of the oil / water heat exchange path 17 between the oil and water channels 8 a and 4 h can have a profiling which is carried out with a view to an improved heat transfer.

The heat exchanger shown in FIG. 2 comprises a valve device 18 by means of which the heat exchange properties of the heat exchanger can be changed, in particular with regard to the oil circuit. The explanations for the heat exchanger according to FIG. 1 apply mutatis mutandis to the details not described in more detail below. For reasons of clarity, the reference numerals of the components which have already been described in connection with FIG. 1 and have not been mentioned repeatedly are not included.

The valve device 18 provided in the heat exchanger according to FIG. 2 enables oil temperature-dependent regulation of the oil flow through the oil heat exchange channels 8 a. , , 8 d. The valve device 18 comprises a closing member 19 via which a passage cross section in a partition 20 can be changed depending on the temperature of the oil in the oil circuit. The passage cross section that can be adjusted by the closing member 19 enables an oil flow between an oil inlet 15 and an oil outlet 16 a while at least partially bypassing the heat exchange channels 8 a provided in the cooling network 1 . , , 8 d.

In the present case, the closing element 19 of the valve device 18 is actuated by a means whose volume and / or geometry changes depending on the heat, for example a wax enclosed in a chamber or a bimetallic body. In the present exemplary embodiment, the valve device is designed such that it closes the passage cross section from a certain temperature, for example 290K. The valve device 18 can also be effective as a pressure relief valve, in order to avoid impermissibly high pressure differences between the oil inlet 15 and the oil outlet 16 a.

In the example shown here, both the oil inlet 15 and the oil outlet 16 a are formed on the first oil end box 9 . The second oil end box 10 is used for the collection and return of the oil heat exchange channels 8 a. , , 8 d pouring oil.

In Fig. 3, a third embodiment of a heat exchanger is shown, in which both oil-heat exchange channels 8 a 'in a section of the cooling network 1 . , , 8 d 'as well as water heat exchange channels 4 i. , , 4 m are arranged.

The section of the cooling network 1 in which the water-heat exchange channels 41 4m extend forms a low-temperature region 21 of the heat exchanger. This low-temperature region 21 is provided with a low-temperature water end box 22 which is integrated into the coolant circuit via a low-temperature water outlet 23 . The supply of the cooling water to the low-temperature water end box 22 takes place via the water heat exchange channels 4 i. , , 4 m from a lower area of the second water box 3 '.

The oil heat exchange channels 8 a '. , , 8 d 'are summarized via end chambers 24 a, 24 b. These final chambers 24 a, 24 b are integrated in an integral end box unit 2 'or 3 '.

The final chambers 24 a, 24 b each form a partition device 25 a, 25 b through which the oil and water circuits are separated. In the partition wall devices 25 a, 25 b through openings are formed through which a fluid flow in or out of the heat exchanger channels 4 i. , , 4 m. The heat exchanger channels 4 i. , , 4 m protrude into the final chambers 24 a, 24 b and divide them into several partitions. 26a. , , 26d and 27a. , , 27d. These partitions 26 a. , , 26 d and 27 a. , , 27 d are connected to one another via through openings 28 , 29 . The cross sections of these through openings 28 , 29 are chosen such that each oil heat exchange channel 4 i. , , 4 m has a predetermined proportion of the total oil flow through the low temperature region 21 . The inflow of the oil to the end chambers 24 a, 24 b arranged in the low-temperature region 21 of the heat exchanger takes place via an oil inlet 15 or an oil outlet 16 . Both the oil flow and the water flow through the combined water-heat exchange channels 4 i in the low temperature range. , , 4 m and oil heat exchange channels 8 a '. , , 8 d 'can be controlled via valve devices. A particularly preferred embodiment of the invention in this regard is described below with reference to FIG. 4.

The construction of the heat exchanger shown in FIG. 4 corresponds broadly to the heat exchanger described above in connection with FIG. 3, the explanations for this apply mutatis mutandis, apart from the differences explained below.

The heat exchanger according to FIG. 4 comprises a valve device 30 for controlling a fluid flow through a through opening 31 . In the exemplary embodiment shown here, the passage opening 31 creates a connection between the lower region of the high-temperature zone 32 of the second water end box 3 'and a low-temperature zone 33 of the heat exchanger. Via this low temperature zone 33 , cooling water is fed into the low-temperature water heat exchange channels 4 i. , , 4 m. The volume flow flowing through these channels is controlled by an actuator 34 . In the present example, the actuator comprises a cylinder filled with wax which is heated by the oil in the area of the partitions 27 a, 27 b. This makes it possible to control the cooling water flow through the low temperature region 21 of the heat exchanger depending on the oil temperature in the oil circuit. The actuator can be designed in such a way that the actuating movements of the valve device 30 caused thereby take account of a predetermined characteristic diagram. In the exemplary embodiment shown, the valve device 30 and the actuator 34 are located on a side of the low-temperature region 21 facing away from the oil inlet. As a result, the oil temperature in the vicinity of the actuator 34 is evened out.

To heat the oil in the oil circuit during a cold start phase, it is possible to bridge the high-temperature zone of the heat exchanger in a thermostat-controlled manner and to supply the cooling water flowing from the internal combustion engine to the low-temperature zone 21 essentially uncooled. A corre sponding fluid guidance is indicated by gray grid in Fig. 4. As an alternative to this, it is also possible to provide a cooling water supply facility in the region of the second water end box 3 ', in particular with direct access to the low-temperature zone 33 . The heat dissipation to the environment is preferably largely suppressed until the cooling water and oil have been sufficiently heated. This can be done by stopping the air flow through the heat exchanger (indicated in FIGS. 1 to 4 by a group of diagonally positioned arrows).

In Fig. 5 shows a detail of a fabricated in lamellar construction is simplified cross-flow heat exchanger shown comprising wherein immediately adjacent fluid paths for separate media circuits. The structure shown here is particularly suitable for the low-temperature zone 21 of the heat exchanger according to FIGS. 2, 3 and 4.

In the section shown, oil heat exchange channels 8 a ', 8 b', 8 c 'are arranged in the immediate vicinity of water heat exchange channels 4 i, 4 j, 4 k. These channels are formed by sheet metal lamellae which are made from an aluminum material in the context of a stamping and deep-drawing process and are connected to one another via soldered connection points.

Air heat exchange channels 35 a, 35 b are formed between the water and oil heat exchange channels. In these air-heat exchange channels 35 a, 35 b are the cooling fin elements 5 already mentioned in connection with FIG. 1 for improving the heat transfer to the ambient air.

The oil heat exchange channels 8 a ', 8 b' and 8 c 'delimited by adjacent sheet metal fins are connected to one another via transverse channels 36 , 37 . The transverse channels 36 , 37 are formed by intermeshed and soldered collar sections 38 , 39 , 40 . The collar sections are formed by deep drawing and punching. The cross channels 36 , 37 stabilize the heat exchanger and evenly fill the oil heat exchange channels 8 a ', 8 b', 8 c '.

The transverse channels 36 , 37 can be arranged offset along the lamellae, as shown in FIG. 5b. As a result, in addition to further stabilizing the heat exchanger, an increase in the heat exchange capacity is achieved, since turbulence within the water heat exchange channels 41 , 4 j, 4 k is caused by the offset of the transverse channels.

The present invention is not based on the previously described embodiment limited examples. The measures in the cooling network water Combine heat exchange channels with oil heat exchange channels, the oil Heat exchange channels in a low temperature area of the cooling network integrate, and in particular the oil in the cooling network through cont Beard water heat exchange channels can heat regardless of that they are partially combined in the described embodiments are also to be regarded as independent invention complexes. this is also valid  for the valve devices described, in particular their arrangement in the End box of the heat exchanger. Under cooling water are in the present case especially engine cooling fluids including largely frost-resistant or to understand boiled media and mixed fluids.

Claims (15)

1. Heat exchanger with a first end box ( 2 ), a second end box ( 3 ), a cooling network ( 1 ) which has cooling channels which extend between the two end boxes ( 2 , 3 ) and an integrated oil heat exchanger device with an oil heat exchange path, the Oil heat exchange path runs through at least a section of the cooling network ( 1 ), and in this section of the cooling network oil heat exchange channels ( 8 a; 8 a ', 8 b', 8 c ', 8 d') and water heat exchange channels ( 4 h ; 4 i, 4 j, 4 k, 4 l) are arranged adjacent to each other for the transmission of a heat flow between at least one oil heat exchange channel ( 8 a; 8 a ', 8 b', 8 c ', 8 d') and a water -Heat exchange channel ( 4 h; 4 i, 4 j, 4 k, 4 l) in the area of the cooling network ( 1 ). 2. Heat exchanger according to claim 1, characterized in that the neighboring heat exchange channels ( 8 a; 8 a ', 8 b', 8 c ', 8 d'; 4 h; 4 i, 4 j, 4 k, 4 l) are separated from each other by a wall made of a metal material. 3. Heat exchanger according to claim 1 or 2, characterized in that the oil heat exchange channels ( 8 a; 8 a ', 8 b', 8 c ', 8 d') adjacent water heat exchange channels ( 4 h; 4 i, 4 j, 4 k, 4 l) form part of a low temperature zone ( 21 ) of the heat exchanger. 4. Heat exchanger according to at least one of claims 1 to 3, characterized in that a valve device ( 18 , 31 ) is provided for controlling the water and / or oil flow through the low temperature zone ( 21 ). 5. Heat exchanger according to at least one of claims 1 to 4, characterized in that an end box device of the oil heat exchanger is received in one of the end boxes ( 2 , 3 ). 6. Heat exchanger according to at least one of claims 1 to 5, characterized characterized in that the heat exchanger with respect to the dissipation of the heat the ambient air is designed as a cross-flow heat exchanger.   7. Heat exchanger according to at least one of claims 1 to 6, characterized in that an upper region of the heat exchanger in the installation position forms a high temperature water / air heat exchange region and a lower region of the heat exchanger in the installation position a low temperature oil / water / air heat exchanger zone ( 21 ) forms. 8. Heat exchanger according to at least one of claims 1 to 7, characterized in that the high-temperature water / air heat exchange area has a high-temperature water outlet, and that the high-temperature water outlet is controlled with a low-temperature water inlet of the oil / water / air heat exchanger zone ( 21 ) is connectable. 9. Heat exchanger in particular according to at least one of claims 1 to 8, with a first end box ( 2 '), a second end box ( 3 '), a cooling network ( 1 ) which has cooling channels which are between the two end boxes ( 2 ', 3 ' ) and an oil heat exchanger device with an oil heat exchange section extending between an oil inlet ( 15 ) and an oil outlet ( 16 , 16 a), the oil heat exchange section having a first oil flow path which extends through the cooling network ( 1 ) extends, and a valve device ( 18 , 31 ) is provided for controlling the oil flow between the oil inlet ( 15 ) and the oil outlet ( 16 , 16 a). 10. Heat exchanger according to claim 9, characterized in that a second Oil flow path is provided which is parallel to the first oil flow path is arranged. 11. Heat exchanger according to claim 9, characterized in that the first Oil flow path and the second oil flow path are arranged in series. 12. Heat exchanger according to at least one of claims 9 to 11, characterized in that the valve device ( 18 ) is designed such that it controls the oil flow flowing via the first oil flow path. 13. Heat exchanger according to at least one of claims 9 to 12, characterized in that the valve device ( 18 , 31 ) comprises an actuator for the temperature-dependent setting of an opening cross section. 14. Heat exchanger according to at least one of claims 9 to 13, characterized characterized in that the actuator comprises an element whose volume is in Changes depending on its temperature. 15. Heat exchanger according to at least one of claims 9 to 14, characterized in that the valve device ( 18 , 31 ) is provided in the region of one of the end boxes ( 2 ', 3 ').