EP1751411B1 - Optimized oil cooling system for an internal combustion engine - Google Patents

Abstract

The present invention provides engine-cooling module assemblies. One engine-cooling assembly includes an engine block and a cooling module including a coolant channel integrated into the engine block. Parallel to the coolant channel is a bypass channel integrated in the engine block and through which a portion of a coolant stream is conducted to an oil/coolant heat exchanger. The present invention also provides a method for cooling oil circulating in an oil circuit of an engine by means of a coolant. The coolant runs through a coolant channel that is formed of both a portion of the engine block and a portion of the cooling module.

Description

The present invention relates to a radiator module for cooling an oil circulating in an oil circuit of an engine by means of a coolant comprising a housing, an oil-coolant heat exchanger, an oil filter and at least one through the module housing and the oil-refrigerant heat exchanger and the oil filter fluidly connecting module coolant channel for transporting the coolant. Further, the invention relates to an engine cooling module assembly for cooling an oil circulating in an oil circuit of an engine by means of a coolant comprising a motor having an engine block and a radiator module connected to the engine block, the radiator module being connected to the engine block such that in the engine extending channels and extending in the module channels are fluidly interconnected to form a closed cooling line system.

Such cooling devices for cooling an internal combustion engine of a motor vehicle are used today in all motor vehicles. In this case, oil is cooled by means of a coolant. Various types of cooling devices are distinguished, for example, with regard to the coolant.

A cooling device according to the prior art is the air-oil cooler. This is arranged on the motor vehicle front in the air flow generated during travel.

A disadvantage of this solution is that the coolant used - air - has a relatively small heat transfer coefficient. To realize a sufficient oil cooling is Therefore, a relatively large-scale air-oil cooler necessary. In addition, the cooling depends on the air flow and thus on the driving speed of the motor vehicle. At low driving speeds, the air-oil cooler does not provide sufficient cooling capacity. The oil must be directed to the air-oil cooler. For this purpose, flexible lines are used by the engine to the air-oil cooler due to the distances to be bridged and the flexible web guide of the oil. These usually designed as a hose flexible conduit tend to leaks after prolonged use.

Another cooling device according to the prior art is the oil-water heat exchanger. This uses water or cooling water as the cooling medium. Due to the higher heat transfer coefficient of water, this heat exchanger has a higher cooling capacity with a smaller construction volume. The coolant, more precisely the water, and oil are fed in a pipe system from hoses or pipes. The use of pipes and hoses is disadvantageous in terms of the connections of the pipes and hoses with each other or with the engine or the oil-water heat exchanger, since the connection tend to leaks relatively quickly, especially at the joints. Furthermore, the flow-mechanical properties of the compounds are disadvantageous, since the compounds sometimes lead to large resistances in the line system.

A third cooling device according to the prior art is the oil-water heat exchanger module with oil filter. This solution overcomes some disadvantages of the previously listed cooling devices. The advantage of the modular design is that the oil-water heat exchanger module has a compact design. The oil filter is designed as a filter cartridge, which is flanged to the heat exchanger. The oil line system is designed as a channel integrated into the module housing, whereby the risk of leaks in relation to the oil line is significantly reduced.

A disadvantage of this solution is that the coolant formed as water is guided and routed here via hoses. This can lead to leaks in the water pipe continue. In addition, due to the strong concentration of the components in a small space to vibration problems during operation of the motor vehicle come, which may lead to failure of the cooling device.

In all the solutions listed above, the flow of media flowing in the channels - coolant / oil - takes place behind one another, that is, in the manner of a series connection. As a result, the channels build longer, resulting in a larger volume. In addition, due to the length of the channels results in a larger total resistance of the conduit system, so that they must also be compensated by a larger dimensioning of the flow cross-sections of the conduit system without accepting a loss of power. However, one goal of such cooling systems besides cooling is to keep the pressure difference in the cooling module as low as possible, since this adds to the total pressure drop in the entire engine system and a pressure drop is a loss of efficiency. The higher the pressure drop, the higher the loss of effectiveness. To ensure this in the conventional systems, the cooling medium flows at high speed through the cooling module, that is, it has a low residence time in the radiator module or radiator pack, whereby the cooling medium can absorb little heat energy and dissipate, and thus causes a little effective cooling , Due to the serial arrangement, moreover, the water cycle in the cylinder block and in the cylinder head must be set separately, that is, it is a reconfiguration of the water cycle in the cylinder block and the cylinder head required. This results in an additional effort on adjustment work.

From the prior art are also the US 5,758,608 as well as the EP 0 243 138 A1 known.

It is therefore an object of the present invention to provide a cooling system in which an efficient cooling of a circulating oil is realized under optimal space utilization.

This object is achieved on the basis of a radiator module according to the preamble of claim 1, an engine radiator module arrangement according to the preamble of claim 6 in conjunction with its characterizing features. Advantageous developments of the invention are specified in the dependent claims. The invention includes the technical teaching that the module coolant channel formed in the housing of the cooler module is at least partially formed as a channel section of the engine coolant channel (5) and partially as a bypass channel (2) fluidically connected to the oil coolant heat exchanger (8). is formed to the engine coolant passage (5) or the module coolant passage to divide the coolant flow into two partial flows, and thus to effect a parallel connection of the coolant flows.

The module coolant channel may have at least in one section an additional bypass channel or be formed completely as a bypass channel. The diversion of the bypass passage may be from a portion of the engine coolant passage formed in the engine block or already branching from the water pump.

As a cooling unit for oil cooling, any other cooling unit suitable for oil cooling can be used in addition to the oil-coolant heat exchanger.

This solution has the advantage that the total length of the line system is shortened by the bypass channel and the associated parallel connection of the coolant. The coolant used for cooling no longer passes through the heat-emitting engine and is then fed to the heat exchanger, but is fed to the heat exchanger in parallel with the passage through the motor. Thus, the temperature of the coolant significantly lower when entering the heat exchanger, whereby a significant improved cooling performance is achieved in the heat exchanger. The coolant used is preferably water. This allows the cooling circuit to be connected directly to the internal water circuit. The water is preferably taken directly behind the water pump. It is therefore advantageous that the bypass channel is arranged as close as possible to the water pump. As a result, the water is still little heated due to the heat that is released from the engine to the cooling water, so that a relatively low water temperature is realized at the inlet of the water in the heat exchanger. Thus, the temperature difference between incoming cooling water and oil to be cooled is greater than in conventional solutions, whereby the cooling performance is significantly improved.

In contrast to conventional cooling systems, the water circuit in the heat exchanger is connected in parallel to the water circuit through the engine block. This means that in contrast to the conventional cooling systems, a high pressure difference is required to leave the engine water cycle unaffected. Due to the high pressure difference results in a longer residence time of the cooling medium in the cooler package or cooler module, whereby a larger amount of heat can be absorbed by the coolant or cooling medium and so a more effective cooling capacity can be realized. Due to the improved heat quantity absorption, fewer cooling plates are required in the cooler module compared to conventional cooling systems for the same cooling performance. As a result, space can be saved. Overall, the invention thus also results in an increase in the cooling efficiency and thus also a reduction of the cost expenditure.

A further measure improving the invention provides that the module coolant channel is designed to be fluidly connected to a corresponding motor coolant channel in a detachable manner, in order to guide the coolant stream flowing through an engine block of the engine through the cooler module. This way you can a part of the already existing engine coolant duct can be used to transport the cooling water. In the area in which the heat exchanger is arranged, the cooling water is then passed through the module to the heat exchanger. This makes it possible to dispense with an external hose assembly, since the motor channel and the bypass channel are each integrated in the module housing. The heat exchanger is preferably arranged in the immediate vicinity of the engine, whereby the bypass channel length is relatively short and a compact engine cooling module arrangement is possible.

It is advantageous that the bypass channel transports a partial flow of the coolant to the oil cooler arranged on the housing and away from it again. The oil cooler is arranged on the radiator module. Due to the parallel connection of the coolant flow, a partial flow is discharged through the bypass channel. This is led to the oil cooler. By discharging the partial flow smaller flow cross-sections can be used in the channels.

Preferably, cooling water is provided as the coolant. This can be branched off from existing cooling water lines, without having to provide an additional coolant circuit with an additional coolant for feeding the coolant circuit.

A particularly improving measure of the invention provides that the oil-refrigerant heat exchanger is at least partially integrated into the module housing. In this way, a very compact radiator module is realized, which has a short channel length. The compact module can be easily assembled and handled without much effort. Due to the at least partial integration of the heat exchanger in the radiator module a safer and more reliable support is ensured, which also ensures an improved vibration behavior of the module.

Preferably, the module housing has at least one integrated oil passage for conducting the oil to and from the oil-refrigerant heat exchanger and / or the oil filter. The fact that the oil channel is also integrated into the housing means that no external lines are required anymore, which further reduces the risk of leaks.

The radiator module according to the invention can be used with an engine block for cooling an oil circulating in an oil circuit of an engine by means of a coolant comprising at least one integrated engine coolant channel for transporting the coolant, wherein the engine coolant channel at least in a portion fluidly with the oil Coolant heat exchanger connected bypass channel to transport or lead one of the two parallel-connected coolant sub-streams to oil-refrigerant heat exchanger and away. The bypass passage should branch as close as possible to the coolant radiator from the engine coolant channel in order to branch off a coolant with the lowest possible temperature.

Such an engine block has the advantage that the bypass channel is formed directly in the engine block or in the engine block housing, so that it is possible to dispense with an additional module. This will require fewer components overall.

The invention further includes the technical teaching that an engine radiator module assembly for cooling an oil circulating in an engine oil circuit by means of a coolant comprising a motor with an engine block, at least one engine coolant passage integrated into the engine block, and fluidly connected to the engine block Radiator module, wherein the radiator module is connected to the engine block, that the at least one engine coolant passage and the at least one module coolant passage or the engine coolant channels and the Module coolant channels are fluidly interconnected to form a closed cooling line system.

Compared to an engine block having an integrated bypass channel, the embodiment listed here is designed in two parts, that is, with a motor and a radiator module. The engine block or the engine block housing can be manufactured with less effort. In addition, the radiator module can be integrated into the engine block, wherein the radiator module or the channels formed in the radiator module replaces a part of the otherwise located in the engine block channels. In this way, the space of the engine cooler module assembly can be further reduced, so that an additional space is created. In this example, designed as a cooler plate package oil-refrigerant heat exchanger can be arranged through which the oil flows.

For this reason, it is advantageous that the cooler module is formed at least partially integrated in the engine block, so that at least a portion of the radiator module is integrated in the engine block, so that the at least one engine coolant passage at least partially through the module coolant channel and / or the bypass channel is replaceable. Due to the at least partial integration of the radiator module in the engine block a reliable and secure mounting of the module is guaranteed. By this arrangement, an optimized with respect to the vibration behavior engine cooling module assembly is realized. The cooler module vibrates less as a result of the partial integration, so that damage or functional impairments caused by vibrations are largely avoided.

A further improvement of the invention provides that in addition at least one control unit is designed to control the flow of oil in the oil circuit. Thus, depending on the need and application, the amount of oil flowing through the oil passage can be controlled.

In practical use of the radiator module results in a cooling method for cooling an oil circuit of an engine by means of a cooling channel formed in a cooling circuit through an oil-refrigerant heat exchanger coolant, comprising an engine block and / or a radiator module comprising the steps of: passing the coolant through a first portion of the refrigeration cycle passing through the engine block, passing the refrigerant through a second portion of the refrigeration cycle passing through the oil cooler and closing the refrigeration cycle, the steps passing the refrigerant through a first portion and passing the refrigerant through a second portion done in parallel. Due to the parallel connection results in a significant improved cooling efficiency, whereby the heat exchanger can be dimensioned with smaller dimensions, so that this effective cooling method can also be used in motor vehicles with little space especially in small cars.

Fig. 1

eine schematische Darstellung eines Motor mit einem erfindungsgemäßen Bypasskanal,

Fig. 2

einen Teilausschnitt einer Mo- tor-Kühlermodulanordnung in einer perspektivischen Ansicht von vorne auf den Motor gesehen,

Fig. 3

ein Kühlermodul in perspektivischer Ansicht von der Motorseite und

Fig. 4

zeigt eine Motor-Kühlermodulanordnung in einer perspektivischen Ansicht von vorne.

Further measures improving the invention are set forth in the subclaims or are presented below together with the description of a preferred embodiment of the invention with reference to the figures. It shows:

Fig. 1

a schematic representation of an engine with a bypass channel according to the invention,

Fig. 2

a partial section of a motor-cooler module arrangement in a perspective view from the front seen on the engine,

Fig. 3

a cooler module in perspective view from the engine side and

Fig. 4

shows an engine radiator module assembly in a perspective view from the front.

Fig. 1 shows a schematic engine radiator module assembly 1 or a motor with integrated bypass channel 2. The engine radiator module assembly 1 and the engine includes a bypass channel 2 for the transport of cooling water. The engine further comprises an engine block 3 and a water pump 4. In the engine block 3, an engine coolant passage 5 for transporting cooling water is formed (schematically represented by white arrows). Bypass duct 2 and engine coolant duct 5 are in Fig. 1 fed via the water pump 4 with cooling water. Thus, the cooling water is divided at the water pump 4 into two partial streams. A partial cooling water flow flows through the engine coolant channel 5 and the other partial flow flows through the bypass channel 2. Both partial flows flow through a common channel section back to the water pump 4. The water pump 4 itself is fed by a cooler (not shown) with cooled cooling water (shown by point line). In the cooling water circuit, a control unit 6 is connected in the form of a thermostat. This causes cooling water, which is no longer used for cooling, to drain to the radiator (shown by dot line). The oil circuit is in Fig. 1 only partially shown. The oil flows through an oil passage 7 through a control unit formed as a throttle 6 to the formed as a thermostat control unit 6. From there, the oil flows further into the oil-refrigerant heat exchanger 8, where it also through the oil-refrigerant heat exchanger. 8 flowing cooling water flow is cooled. The bypass channel 2 can be integrated both in the engine block 3 and separately in an in Fig. 2 shown cooler module integrated with the engine to be connected.

Fig. 2 shows a partial section of an engine-radiator module assembly 1 comprising a radiator module 9 which is attached to a motor - more precisely attached to an engine block 3 - by means of a screw connection. The cooler module 9 comprises a module housing 10 in which the bypass channel 2 (not visible here) and the oil passage 7 extend. Integrated into the cooler module 9 is an oil filter 11. This is designed in the manner of a cartridge.

The radiator module 9 is viewed from the engine side in Fig. 3 shown.

Fig. 3 shows the radiator module 9 in a perspective view. The radiator module 9 includes an oil filter 11 and a housing 10 in which the bypass passage and the oil passage (both not shown) are arranged. On the housing 10, a channel portion section for discharging the coolant or the oil is arranged.

Fig. 4 shows a motor-cooler module assembly with a built-in motor cooler module 9. The engine in Fig. 4 For example, an engine block 3 includes a water pump 4, a cover 12, a heat shield shield 13, a cylinder block 14 with a cylinder head 15, and an oil pan 16. The radiator module 9 is largely integrated with the engine, with only the oil filter 11 and portions of the channels protrude from the engine.

LIST OF REFERENCE NUMBERS

1

Engine cooler module arrangement

2

bypass channel

3

block

4

water pump

5

Engine coolant channel

6

control unit

7

oil passage

8th

Water-oil heat exchanger

9

cooler module

10

module housing

11

oil filter

12

cover

13

Manifold with heat shield

14

cylinder block

15

cylinder head

16

oil pan

Claims (8)

1. A radiator module (9) for cooling oil circulating in an oil circuit of an engine by means of a cooling medium flow flowing through a cooling medium conduit (5) of the engine, comprising a module housing (10), an oil cooling medium heat exchanger (8) connected with the module housing (10), an oil filter (11) connected with the module housing (10), and at least one cooling medium conduit of the module extending through the module housing (10) and leading to the oil cooling medium heat exchanger (8) and the oil filter (11) for the transport of the cooling medium through the module housing (10), characterized in that the cooling medium conduit of the module is arranged at least partly as a partial conduit section of the cooling medium conduit (5) of the engine and partly as a bypass conduit (2), which is connected in a fluidic manner with the oil cooling medium heat exchanger (8), to the cooling medium conduit (5) of the engine or the cooling medium conduit of the module in order to divide the cooling medium flow into two partial flows and thus cause a parallel switching of the cooling medium flows.
2. A radiator module (9) according to claim 1, characterized in that the cooling medium conduit of the module is arranged to be detachably connected in a fluidic manner with a corresponding cooling medium conduit (5) of the engine in order to guide the cooling medium flow, which flows through an engine block (3) of the engine, through the radiator module (9).
3. A radiator module (9) according to claim 1 or 2, characterized in that cooling water is provided as the cooling medium.
4. A radiator module (9) according to claim 1, characterized in that the oil cooling medium heat exchanger (8) is integrated at least partly in a module housing (10).
5. A radiator module (9) according to claim 4, characterized in that the module housing (10) comprises at least one integrated oil conduit (7) for guiding the oil to and from the oil cooling medium heat exchanger (8) and/or the oil filter (11).
6. An engine radiator module arrangement (1) for cooling oil circulating in an oil circuit of an engine by means of a cooling medium, comprising an engine with an engine block (3), at least one cooling medium conduit (5) of the engine which is integrated in the engine block (3), and a radiator module (9) according to one of the claims 1 to 5 which is connected in a fluidic manner with the engine block (3), with the radiator module (9) being connected with the engine block (3) in such a way that the at least one cooling medium conduit (5) of the engine and the at least one cooling medium conduit of the module are connected with each other in a fluidic manner in order to form a closed cooling medium line system.
7. An engine radiator module arrangement (1) according to claim 6, characterized in that at least one region of the radiator module (9) is arranged to be integrated in the engine block (3), so that the at least one cooling medium conduit (5) of the engine can be replaced at least partly by the cooling medium conduit of the module and/or the bypass conduit (2).
8. An engine radiator module arrangement (1) according to claim 6 or 7, characterized in that in addition at least one closed-loop control unit (6) is provided for controlling the oil flow in the oil circuit.

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