EP2876274B1 - Internal combustion engine - Google Patents

Description

The invention relates to an internal combustion engine with a cooling system.

Internal combustion engines for motor vehicles have at least one cooling system in which a coolant is pumped by means of one or more pumps in at least one cooling circuit and thereby absorbs heat energy from integrated into the cooling circuit components, in particular the internal combustion engine and an oil cooler and / or a charge air cooler. This heat energy is then in an ambient heat exchanger, the so-called main water cooler, and temporarily in a heating heat exchanger to the ambient air, in the case of the heating heat exchanger to the provided for air conditioning of the interior of the vehicle ambient air specified.

Cooling systems of modern motor vehicles generally have several cooling circuits. For example, it is known to provide a so-called large or main cooling circuit and a small cooling circuit, which are partially formed integrally, and wherein the coolant is guided either via the large or the small cooling circuit by means of a thermostat-controlled valve. This is done as a function of the temperature of the coolant, so that, for example, in a warm-up phase of the internal combustion engine, when the coolant has not yet reached its operating temperature range, this is conveyed in the small cooling circuit, whereby the main water cooler, i. the ambient heat exchanger, in which the coolant is mainly cooled by heat transfer to the ambient air, is bypassed. On the other hand, if the coolant has reached its operating temperature range, the coolant in the large customer group is conveyed by means of the thermostat-controlled valve, so that overheating of the cooling system is avoided by a heat transfer from the coolant to the ambient air. By contrast, the heating heat exchanger as the second ambient heat exchanger is regularly integrated into the small cooling circuit, which enables the interior of the motor vehicle to be heated even in the warm-up phase of the internal combustion engine.

The (main) pump of the cooling system is regularly mechanically driven by the internal combustion engine of the internal combustion engine. Your output is thus in principle proportional to the speed at which a crankshaft of the internal combustion engine rotates. Although with increasing speed of the internal combustion engine also the cooling power demand tends to increase, the theoretically achievable by the operation of the pump cooling performance in many operating conditions does not correspond to the actual cooling power requirement. Since a sufficiently high cooling capacity should be available in all operating states, such mechanically driven pumps are often oversized. The efforts to reduce the fuel consumption of motor vehicles, has therefore led to the development of mechanically driven Kuhlmittelpumpen that are adjustable in terms of the volume flow rate. Such a controllable, mechanically driven coolant pump is for example from the DE 10 2010 044 167 A1 known

In the cooling systems of modern motor vehicles, the main control of the volumetric flow of the coolant thus takes place by means of controllable coolant pumps while the distribution of the volumetric flow is controlled to the individual, each having a different cooling demand component cooler by means of active and in particular controlled by thermostats valves. For example, the DE 103 42 935 A1 an internal combustion engine with a cooling circuit comprising a mechanically driven by an internal combustion engine pump. The delivery volume flow of the pump is thus dependent on the speed of the internal combustion engine. In order to achieve individually adapted volumetric flows of the coolant for a plurality of heat exchangers integrated in the cooling circuit, in particular cooling ducts of a cylinder crankcase and a cylinder head of the internal combustion engine and a heating heat exchanger for an interior heating of a motor vehicle driven by the internal combustion engine, a plurality of individually controllable control valves are provided in the Integrated cooling circuit. The DE 103 42 935 A1 further discloses that the passages of the cylinder crankcase and the cylinder head are connected in parallel, thereby making it possible to individually control the cooling capacity for these components. That from the DE 103 42 935 A1 known cooling system is relatively expensive. Internal combustion engines, with regard to the design of the respective cooling system to the internal combustion engine according to the DE 103 42 935 A1 are comparable, are also in the DE 10332 947 A1 , of the DE 10 20008 048 373 A1 and the DE 198 31 901 A1 disclosed.

From the DE 199 06 523 A1 In addition, a cooling system for a motor vehicle is known which comprises two cooling circuits, namely a main cooling circuit comprising the main water cooler, a main coolant pump and cooling channels of an internal combustion engine and a secondary cooling circuit comprising a heating heat exchanger for an interior heating of the motor vehicle. The further an auxiliary heater and a separate, electrically operated pump having secondary cooling circuit is designed as a short circuit, ie by means of an actively controllable valve, the auxiliary cooling circuit is operable independently of the main cooling circuit.
And finally, in the US 2012/0103283 A1 discloses a cooling system for an internal combustion engine in which a cylinder head of the internal combustion engine, a housing of an exhaust gas turbine, a heat exchanger and a mechanically driven main coolant pump are integrated into a first cooling circuit and a cylinder crankcase and a controllable auxiliary coolant pump are integrated into a second coolant circuit bypassing the main coolant pump.
For a good and in particular efficient cooling performance of a cooling circuit, it is relevant that this is vented as completely as possible. Accordingly, during the filling process of the cooling circuit, in particular during initial filling or refilling as part of maintenance, the air contained in the cooling circuit, which is displaced by the inflowing coolant, must be removed as completely as possible. In addition, during operation of the motor vehicle and thus of the cooling circuit, gas can be produced by evaporation processes, which should be safely dissipated. This is especially true if the cooling circuit is designed for an operating temperature of the coolant, which is above the (pressure-dependent) boiling point of water. Water that has accumulated or settled in the cooling circuit, then evaporates and should be discharged accordingly.
A ventilation of a cooling circuit is carried out regularly via a surge tank of the cooling system. Such a reservoir also has the task of compensating for the different thermal expansion of the coolant and is partially filled with air. For venting can lead a vent line of usually the highest point of the cooling circuit to the even higher arranged surge tank.
Based on this prior art, the present invention seeks to provide a simple as possible adjustable cooling system for a motor vehicle.
This object is achieved by a cooling system according to independent claim 1. Methods for operating such a cooling system are the subject of claims 8, 10 and 11. Advantageous embodiments of the cooling system according to the invention and advantageous method for operating individual of these embodiments are objects of the further claims and will become apparent from the following description of the invention.

The invention is based on the idea to obtain as simple as possible all temperature-controlled valves as simple as possible cooling system. Here is an underlying recognition of the invention that can be done by a suitable integration of at least two controllable coolant pumps without such temperature-controlled valves individual control of the flowing through the individual component cooler volume flow of the coolant and thus the Kuhlleistungsbedarf for these component. It is important that the at least two controllable pumps are integrated into different cooling circuits, which are partially formed integrally, so that by the mutual influence or superposition of the volume flow generated by the individual coolant pumps or pressure of the coolant an individual control of the individual Component cooler flowing volume flow can be done.

Accordingly, a cooling system for an internal combustion engine having a component heat exchanger, a primary water cooler formed as an ambient heat exchanger and a first pump comprising the first cooling circuit and a component and a second pump second cooling circuit, the cooling circuits are integrally formed in at least a portion and in the cooling circuits a coolant for promoting is provided or is promoted, characterized in that the pumps are designed controllable and can be done by the or the component and the ambient heat exchanger flowing volume flows of the coolant by means of (mutually) adapted operation of the at least two pumps or takes place ,

The term "radiator" heat exchangers are understood according to the invention, which allow heat transfer in both directions, ie from a component to the coolant and from the coolant to the component. The term "cooler" is chosen, since during normal operation of the internal combustion engine, ie when this has reached its operating temperature range, a heat transfer from the component to the coolant is provided and the heat exchanger to effect cooling of the components. In another operating phase of the internal combustion engine, in particular in a warm-up phase or during operation with very low power, however, a heat transfer from the coolant to the respective component can be provided. As a result, in particular a rapid heating of the component can be achieved.

The cooling system of the internal combustion engine according to the invention comprises a first component cooler, which is arranged in the integral portion of the two cooling circuits. In this case, the first component cooler comprises a first Teilkomponentenkühler and a second Teilkomponentenkühler, wherein the Teilkomponentenkühler are connected in parallel. The first Teilkomponentenkühler is a cooler of a cylinder crankcase (in particular in the form of integrated into the cylinder crankcase cooling channels formed) and the second Teilkomponentenkühler to a radiator of a cylinder head (in particular in the form of integrated in the cylinder head cooling channels) of an internal combustion engine of the internal combustion engine ,

An advantageously usable for the formation of such a cooling system connection element which can be connected in particular to the outside of an internal combustion engine of the internal combustion engine, has at least one two separate flow spaces forming (one or more parts) housing, wherein a first of the flow spaces with at least two inlet ports, both (in particular alternatively) can be shut off by means of a device for preventing backflow, and is connected to an outlet port. On the other hand, a second of the flow spaces is connected to at least two inlet connections, one of which can be shut off by means of a pressure-actuated shut-off element, and at least two outlet connections.

In such a connection element, a temperature sensor can furthermore preferably be arranged in (or at least in the vicinity of) at least one of the two inlet connections connected to the second flow space. This may in particular be that inlet connection which connects a cooling channel of the cylinder head of the internal combustion engine with the second flow chamber.

In a preferred embodiment of the cooling system of the internal combustion engine according to the invention can be provided that the at least two pumps are driven by an electric motor. This allows a particularly simple and accurate control of the individual pumps and thus also the adapted operation of the at least two pumps. It is also possible, one, several or all of the pumps mechanically run by, for example, an internal combustion engine of the internal combustion engine, the controllability of the delivery rates of these pumps by other means (see, for example DE 10 2010 044 167 A1 ) can be achieved.

In an internal combustion engine according to the invention can vorteithafterweise be provided that in a warm-up phase of the internal combustion engine mainly or exclusively the pump of the second cooling circuit is operated while the pump of the first cooling circuit is not or only operated with low power. The then a significant Dresselwirkung having pump of the first cooling circuit largely prevents that a relevant volume flow of the coolant through the ambient heat exchanger, which is the so-called main water cooler, is performed. As a result, such an undesired cooling of the coolant in the ambient heat exchanger during the warm-up phase of the internal combustion engine can be prevented and a rapid heating of the coolant can be supported.

In particular, when the throttling action of a low power or not operated pump is sufficient to sufficiently prevent flow through the associated cooling circuit, in a preferred embodiment of the cooling system of the present invention means for preventing backflow of the coolant from the integral one Section be provided in one or both cooling circuits. These means can be designed, for example, in the form of check valves integrated into the cooling circuit (s). If the means are integrated directly into a mouth portion of the integral portion, there is also the advantageous possibility to form them in the form of a flap valve that is pressure-dependent pivotable and thereby either the orifice of the first or the second cooling circuit (at least partially) closes.

It can preferably be provided that a heating heat exchanger is integrated in the second cooling circuit of the cooling system. Thus, it can be ensured that, if necessary, during the warm-up phase of the internal combustion engine, heat energy can be transferred from the cooling circuit to ambient air provided for conditioning an interior of the motor vehicle.

The warm-up phase of the internal combustion engine may further preferably in a first phase in which the pump of the second cooling circuit with a relatively low flow rate and thus a correspondingly low flow rate of the coolant is operated, and a second phase in which the pump of the second cooling circuit with a relative high flow rate and thus a correspondingly high flow rate of the coolant is operated, be divided. As a result, it can be achieved, for example, that in the first phase, which is preferably prior to the second phase, by means of only a very small flow through, in particular, of an internal combustion engine and particularly preferably a cylinder head of the Internal combustion engine, a rapid heating of this component is achieved, which can have a positive effect on the fuel consumption and the exhaust emissions of the internal combustion engine. In this case, the regulation of the delivery rate of the pump of the second cooling circuit can in particular also be effected as a function of an ambient temperature and a setpoint temperature for the interior of the motor vehicle. If a heating power for the interior is provided depending on the difference between the ambient temperature and the target temperature for the interior, the pump of the second cooling circuit can be operated at a higher power in said first phase of the warm-up phase, as is the case no heating power is necessary.

The second phase of the warm-up phase with a different, relatively higher flow rate of the pump of the second cooling circuit and thus a higher volume flow of the coolant through the second cooling circuit can be started in particular when (initially) sufficient heating of the internal combustion engine and in particular of the cylinder head has been achieved and / or no particularly high heating power for the interior of the motor vehicle is required more. Then, the heat energy absorbed by the coolant in the internal combustion engine may preferably be utilized for rapid heating of another component, such as the engine oil. For this purpose, a corresponding further component cooler, in particular an engine oil cooler, can be integrated into a connecting section connecting the two cooling circuits. In this case, the integration of the connection section preferably takes place in such a way that the coolant flowing over the further component cooler can circulate, without being led over the ambient heat exchanger of the first cooling circuit.

If the cooling system of the internal combustion engine according to the invention, as usual in the prior art, has a surge tank, may preferably be provided that this is integrated into a section in which no relevant volume flow of the coolant is provided in the warm-up phase of the internal combustion engine. In particular, the expansion tank can be integrated into the first cooling circuit parallel to the ambient heat exchanger. This can avoid that during the warm-up phase, the coolant to be heated as quickly as possible is promoted by the surge tank to a relevant extent, which can otherwise be associated with a not inconsiderable, in this phase of operation of the engine undesirable cooling of the coolant.

The inventive design of the cooling system of an internal combustion engine has in such a positioning of the surge tank still has the advantage of easy feasible ventilation of the cooling system in a new or refill. In particular, it may be provided that during or after the filling of the cooling circuit with the coolant, the (not of the internal combustion engine and in particular electrically driven) pump of the first cooling circuit is operated without the internal combustion engine of the internal combustion engine is operated (non-operation of the internal combustion engine). This simplifies the filling process. In internal combustion engines with conventional cooling systems, on the other hand, usually for venting after refilling or refilling the cooling system, the internal combustion engine must be operated to operate the (main) pump of the cooling system, through which then the coolant and by means of the coolant contained in the cooling system Air is conveyed in the direction of the expansion tank.
In the cooling system of the internal combustion engine according to the invention it is provided that the volume flow of the coolant through the first Teilkomponentenkühler by means of a pressure-controlled valve in dependence on the flow rate through the second Teilkomponentenkühler is regulated, so that a relevant flow through the radiator of the cylinder crankcase with the coolant takes place only when the flow through the radiator of the cylinder head has exceeded a defined limit.
By means of such a cooling system, a preferred embodiment of the method according to the invention can be realized, in which the flow rate of the pump of the first cooling circuit is controlled by the temperature of the coolant at the output of the second Teilkühlkomponente (for which the or the cooling circuits have at least one appropriately arranged temperature sensor) and a Volumetric flow is controlled by the first part of the component cooler by means of a matched operation of the pump of the second cooling circuit. Thus, it can be provided that the temperature of the cylinder head, which is reflected in the temperature of the coolant at the outlet of the radiator of the cylinder head, is used as one or the relevant controlled variable for the pump of the first cooling circuit, wherein a control of the cooling capacity of the radiator of the cylinder head and thus the temperature of the cylinder head can be advantageously controlled by the flow rate of this pump. To decouple this regulation from the regulation of the cooling capacity of the radiator of the cylinder crankcase, then the pressure in the integral portion of the cooling circuits can be varied by means of the pump of the second cooling circuit, that the pressure-controlled valves in a defined scope opens or closes and thus regulates the flow through the radiator of the cylinder crankcase.

The indefinite articles ("a", "an", "an" and "an"), in particular in the patent claims and in the description generally describing the claims, are to be understood as such and not as numerical words. Corresponding to this concretized components are thus to be understood that they are present at least once and may be present more than once.

Fig. 1:

eine Brennkraftmaschine mit einem erfindungsgemäßen Kühlsystem in einer schematischen Darstellung;

Fig. 2:

eine bauliche Umsetzung eines Teils des Kühlsystems der Fig. 1 in einer perspektivischen Ansicht;

Fig. 3:

in isolierter Darstellung das Anschlusselement des Kühlsystems gemäß der Fig. 2;

Fig. 4:

eine Prinzipdarstellung eines ersten Strömungsraums des Anschlusselements gemäß der Fig. 3;

Fig. 5:

eine Prinzipdarstellung eines zweiten Strömungsraums des Anschlusselements gemäß der Fig. 3;

Fig. 6:

die Durchströmung eines Teils des Kühlsystems gemäß der Fig. 1 in einem ersten Betriebszustand der betriebswarmen Brennkraftmaschine;

Fig. 7:

die Durchströmung eines Teils des Kühlsystems gemäß der Fig. 1 in einem zweiten Betriebszustand der betriebswarmen Brennkraftmaschine;

Fig. 8:

die Durchströmung des Kühlsystems gemäß der Fig. 1 in dem ersten und zweiten Betriebszustand der betriebswarmen Brennkraftmaschine;

Fig. 9:

eine nicht erfolgende Durchströmung des Kühlsystems gemäß der Fig. 1 in einer ersten Phase einer Warmlaufphase der Brennkraftmaschine;

Fig. 10:

die Durchströmung des Kühlsystems gemäß der Fig. 1 in einer zweiten Phase der Warmlaufphase der Brennkraftmaschine; und

Fig. 11:

die Durchströmung des Kühlsystems gemäß der Fig. 1 in einer dritten Phase der Warmlaufphase der Brennkraftmaschine.

The present invention will be explained in more detail with reference to embodiments shown in the drawings. In the drawings, each schematically shows:

Fig. 1:

an internal combustion engine with a cooling system according to the invention in a schematic representation;

Fig. 2:

a structural implementation of a part of the cooling system of Fig. 1 in a perspective view;

3:

in isolation, the connection element of the cooling system according to the Fig. 2 ;

4:

a schematic representation of a first flow space of the connecting element according to the Fig. 3 ;

Fig. 5:

a schematic representation of a second flow space of the connecting element according to the Fig. 3 ;

Fig. 6:

the flow through a part of the cooling system according to the Fig. 1 in a first operating state of the warm-running internal combustion engine;

Fig. 7:

the flow through a part of the cooling system according to the Fig. 1 in a second operating state of the warm operating internal combustion engine;

Fig. 8:

the flow through the cooling system according to the Fig. 1 in the first and second operating states of the warm operating internal combustion engine;

Fig. 9:

a non-passing through the cooling system according to the Fig. 1 in a first phase of a warm-up phase of the internal combustion engine;

Fig. 10:

the flow through the cooling system according to the Fig. 1 in a second phase of the warm-up phase of the internal combustion engine; and

Fig. 11:

the flow through the cooling system according to the Fig. 1 in a third phase of the warm-up phase of the internal combustion engine.

The Fig. 1 shows an internal combustion engine with a cooling system according to the invention, wherein in addition to the cooling system still an internal combustion engine 10 of the internal combustion engine is shown The internal combustion engine 10 may be designed as a conventional reciprocating internal combustion engine and then comprises a cylinder crankcase 12 in which a plurality of cylinders (not shown) are formed In each of which a piston (not shown) is movably guided A cylinder head 14 closes the cylinder crankcase 12 and thus the cylinder upwards and further comprises at least one inlet and at least one exhaust valve for each of the cylinders, in a known manner Gas change is controlled in trained by the cylinders and the piston combustion chambers.

Both the cylinder crankcase 12 and the cylinder head 14 are cooled by means of the cooling system, to which these cooling channels 58, 60 have, which are filled with the coolant of the cooling system and flows through this at least temporarily. The (at least one) cooling passage 60 of the cylinder crankcase 12 and the (at least one) cooling passage 58 of the cylinder head 14 are formed to run parallel and thus are also parallel to the coolant flows through.

The cooling system forms a first cooling circuit and a second cooling circuit, which are formed integrally in a section, specifically in the section formed by the cooling channels 58, 60 of the internal combustion engine 10. Accordingly, during operation of the cooling system, the cooling channels 58, 60 of the internal combustion engine 10 at least partially flows through, regardless of whether only the first or the second or both cooling circuits are used.

The first cooling circuit further comprises an ambient heat exchanger, which is provided as a so-called main water cooler 16, and a first, electrically driven and in terms of their capacity adjustable pump 18, which is arranged downstream of the main water cooler 16. Furthermore, a surge tank 20 is provided, which is integrated in a parallel connection to the main water cooler 16 in the first cooling circuit. The individual components of the first cooling circuit are fluid-conductively connected via corresponding connection lines.

The second cooling circuit also comprises a heating heat exchanger 22, which also constitutes an ambient heat exchanger, with which, if necessary, a heat transfer from the coolant to ambient air, which is provided for the air conditioning of an interior of a motor vehicle driven by the internal combustion engine, can take place. Furthermore, the second cooling circuit comprises a second, electrically driven and with regard to their delivery rate controllable pump 24, which is arranged downstream of the heating heat exchanger 22. The individual components of the second cooling circuit are fluid-conductively connected via corresponding connecting lines

The cooling system further comprises an intermediate cooling circuit formed by the integral portion of the first and second cooling circuits, another section of the first cooling circuit, another section of the second cooling circuit, and a connecting section (with corresponding connection lines) connecting the first cooling circuit and the second cooling circuit , In this case, based on the flow direction of the coolant, the connecting portion downstream of the internal combustion engine 10 and upstream of the main water cooler 16 and the surge tank 20 from the first cooling circuit. The mouth of the connecting portion is integrated downstream of the heat exchanger 22 and upstream of the pump 24 (and thus also upstream of the engine 10) in the second cooling circuit. In the connecting portion of the intermediate cooling circuit, a further component cooler in the form of a motor oil cooler 26 is integrated. The engine oil cooler 26 is used in the operation of the internal combustion engine after reaching the operating temperature range cooling the used for lubricating the engine 10 engine oil.

To form the integral portion of the first and second cooling circuits, a connection element 28 is provided, which in the Fig. 3 shown in isolation. From a housing 30 of the connecting element 28, which is provided for a lateral flanging to the internal combustion engine 10, a first flow space 32 and a second flow space 34, which are separated from each other, are formed.

As is clear from the 4 and 5 results, the first flow space 32 with two inlet ports 36, 38 is connected, of which a first, the inlet port 36, serves as a supply of coolant from the first cooling circuit and the second, the inlet port 38, as a supply of coolant from the second cooling circuit. An outlet port 40 connected to the first flow space 32 is closed to a cooling passage 62 of the engine 10. This cooling channel 62 of the internal combustion engine 10 is provided upstream of a branch 64, which serves for a division of the coolant to the parallel cooling channels 58, 60 of the cylinder crankcase 12 and the cylinder head 14. Within the first flow space 32, a valve flap 42 is furthermore provided, which is pivoted in the direction of one or the other inlet port 36, 38 as a function of the pressure difference of the coolant entering the first flow space 32 from the first cooling circuit and the second cooling circuit.

In the Fig. 1 and 6 to 11 is shown that instead of the valve flap 42, two check valves 44 can be used, of which one of the two inlet ports 36, 38 is assigned.

The second flow space 34 is also fluid-conductively connected to two inlet ports 46, 48, wherein a first, the inlet port 46, fluidly connected to the cooling channel 28 of the cylinder crankcase 12 and the second, the inlet port 48, fluidly connected to the cooling channel 58 of the cylinder head 14 is connected to the cooling passage 60 of the cylinder crankcase 12 inlet port 46 closed by means of a pressure-actuated valve 50. The valve 50 comprises a valve body, which is acted upon by means of a prestressed spring element in the direction of an orifice opening of this inlet connection 46. Furthermore, the second flow space 34 is fluidly connected to three outlet ports 52, 54, 56, of which a first, the outlet port 52, the discharge of coolant from the second flow space 34 in the first cooling circuit, a second, the outlet port 54, for discharging Coolant from the second flow space 34 in the second cooling circuit and the third, the outlet port 56, for discharging coolant in the engine oil cooler 26 comprehensive connecting portion of the intermediate cooling circuit is used.

The cooling system shown in the drawings works completely without temperature-controlled valves. A regulation of the volume flows of the coolant conducted via the individual component coolers and heat exchangers, and thus the corresponding cooling or heat exchange rates, is achieved exclusively via adapted power control of the two pumps 18, 24.

The 6 and 7 show ways to control the cooling capacity of the cylinder crankcase 12 and the cylinder head 14 by flowing through the flow rates of the coolant. The pressure-actuated valve 50 in the second flow space 34 of the connection element 28 opens the inlet connection 46 connected to the cooling channel 60 of the cylinder crankcase 12, for example, only at a pressure difference of approximately 200 mbar. Such an overpressure in the cooling passage 60 of the cylinder crankcase 12 can be achieved, for example, when the volume flow of the coolant through the cooling passage 58 of the cylinder head 14 is at least 15 l / min. In the Fig. 6 For example, it is shown that such a volume flow through the cooling channel 58 of the cylinder head 14 of up to 15 l / min can be achieved by a combined operation of both pumps 18, 24. It can be provided in particular that the greater proportion of the volume flow is achieved by the delivery rate of the pump 18 of the first cooling circuit. However, it may also be possible to achieve the entire volume flow of the coolant through the cooling channel 58 of the cylinder head 14 exclusively by the operation of one of the two pumps 18, 24. If, on the other hand, a volume flow through the cooling channel 58 of the cylinder head 14 of 15 l / min is exceeded, the pressure-actuated valve 50 opens and thus enables the coolant channel 60 of the cylinder coghouse 12 to be flowed through by the coolant. This volume flow of the coolant through the cooling passage 60 of the cylinder crankcase 12 may in particular be smaller than the volume flow of the coolant through the cooling passage 58 of the cylinder head 14. In the Fig. 7 is shown that the entire volume flow is generated by the internal combustion engine 10 in about half of each of the two pumps. Any other division is possible by a corresponding control of the pumps 18, 24.

In particular, it may be provided to effect a control of the pump 18 of the first cooling circuit as a function of the temperature of the coolant emerging from the cooling passage 58 of the cylinder head 14. For this purpose, a temperature sensor (not shown) is integrated in the inlet connection 48 of the connection element 28 connected to the cooling channel 58 of the cylinder head 14. Its measuring signal can be transmitted to a control device (not shown), for example a central engine control of the internal combustion engine, which activates the pump 18 of the first cooling circuit as a function of this measuring signal. The delivery rate of the pump 18 of the first cooling circuit can thus be continuously adjusted so that the emerging from the cooling channel 58 of the cylinder head 14 coolant and thus the cylinder head 14 itself is in a defined operating temperature range, Whether at the same time the Zylinderkurbeigehäuse 12 - and if so , with what volume flow - of the coolant is flowed through and thus a cooling of the cylinder crankcase 12 is to take place, then, for example, exclusively by means of a corresponding, the control of the pump 18 of the first cooling circuit superimposed control of the pump 24 of the second cooling circuit. For this purpose, a temperature sensor (not shown) may be provided in the inlet port 46 of the connection element 28 connected to the cooling channel 60 of the cylinder crankcase 12, the measurement signal of which is transmitted to a control device (not shown), in particular the engine control of the internal combustion engine, which then activates a corresponding control the pump 24 of the second cooling circuit makes.

Such an operation of the cooling system makes sense in particular after reaching a defined, intended for continuous operation operating temperature range of the internal combustion engine. The Fig. 8 clarifies again the then taking place flow through the first and the second cooling circuit and the intermediate cooling circuit,

A regulation of the cooling capacity of the engine oil cooler 26 and thus the temperature of the engine oil during operation of the internal combustion engine in its operating temperature range can be achieved due to the selected configuration of the intermediate cooling circuit in particular by a corresponding control of the pump 24 of the second cooling circuit. For example, for the operation of the internal combustion engine in its operating temperature range, boundary volume flows for the flow through the engine oil cooler 26 of 1.5 l / min and 8 l / min can be provided.

An operation of the cooling system, in which the first and the second cooling circuit and the intermediate cooling circuit are flowed through by the coolant, can also be used for ventilation after a new or refilling of the cooling system, which may be done for example in the context of the new production or maintenance of the internal combustion engine By circulating the coolant, air that is still within the cooling system is entrained and gradually supplied to the surge tank 20 where it is separated from the coolant. Since both pumps 18, 24 of the cooling system are electrically driven and regulated, the recirculation of the coolant in the cooling system can also take place without an operation of the internal combustion engine 10.

The Fig. 9 to 11 In contrast, show an operation of the cooling system in a warm-up phase of the internal combustion engine, ie in one operation (especially after a cold start) with not yet reached operating temperature range. It is provided that then either no or only the pump 24 of the second cooling circuit is operated. This results in a cooling medium resting in the cooling system or a circulation of coolant in the second cooling circuit and in the intermediate cooling circuit, but not in the first cooling circuit. The non-operation of the pump 18 of the first Kohlkreises in connection with the resulting closure of the first cooling circuit with the first flow chamber 32 of the connecting element 28 connecting inlet port 36 through the valve flap 42 (or the corresponding check valve 44) prevents in an operation of the pump 24 of the second cooling circuit effectively a flow through the main water cooler 16 and the surge tank 20 and thus an undesirable during the warm-up phase cooling of the coolant through these components.

The warm-up phase is divided into at least two, preferably three phases. In a first phase directly following the cold start (cf. Fig. 9 ) may be provided to operate none of the pumps 18, 24, whereby the coolant in the entire cooling system largely rests. As a result, particularly rapid heating of the cylinder head 14 and also of the cylinder crankcase 12 can be achieved by the waste heat of the combustion processes taking place in the combustion chambers of the internal combustion engine 10.

Shortly afterwards, in a second phase (cf. Fig. 10 ), the pump 24 of the second cooling circuit with a relatively low flow rate are put into operation. As a result, a small volume flow of the coolant is to be achieved by the cylinder head 14, whereby local overheating of the cylinder head 14 can be avoided. A volume flow of the coolant through the cylinder crankcase 12 is not provided in this phase.

As soon as a defined minimum limit temperature has been reached for the cylinder head 14, which can be determined by measuring the temperature of the coolant emerging from the cooling passages of the cylinder head 14, the third phase (cf. Fig. 11 ) of the warm-up phase are introduced, which differs from the second phase by a higher capacity of the pump 24 of the second cooling circuit. In this phase can be provided in particular, after reaching the minimum limit temperature for the cylinder head 14 to achieve a defined operating temperature range for the engine oil as quickly as possible. For this purpose, with the then in comparison to the second phase then larger volume flow of the coolant increasingly heat energy, which receives the coolant in the cylinder head 14, discharged in the engine oil cooler 26 to the engine oil. Also in this phase can be provided that no flow through the cylinder crankcase 12 takes place with the coolant.

An operation of the cooling system according to this third phase may also be provided after reaching the operating temperature range of the internal combustion engine, when the internal combustion engine 10 is operated over a longer period of very low power. As a result, an excessive drop in the temperature of the engine oil can be prevented.

Furthermore, it can also be provided that heat energy stored in a heat accumulator, not shown in the drawings, which is integrated in the cooling system and in particular in the second cooling circuit and / or the intermediate cooling circuit (and which, for example, in or shortly after a previous operation of the internal combustion engine) the heat storage was stored), is discharged to the coolant. In order to achieve a distribution of these previously stored heat energy in the second cooling circuit and the intermediate cooling circuit, it can preferably be provided that such a discharge of the heat accumulator is combined with an operation of the pump 24 of the second cooling circuit with at least relatively low flow rate. Thus, it can be provided in particular to integrate a discharge of a heat accumulator in the previously described, second phase of the warm-up phase. If appropriate, the first phase described above can then be dispensed with, whereby the second phase with the discharge of the heat accumulator would become the first phase of the warm-up phase.

If such a heat accumulator is integrated in the cooling system and in particular in the second cooling circuit and / or the intermediate cooling circuit, it may be provided, after the end of the operation of the internal combustion engine (especially if this had reached its operating temperature range during operation), the pumps 18, 24 and In particular, to let the pump 24 of the second cooling circuit to run after a defined period of time, This makes it possible to transfer the heat energy remaining in the coolant and in the operation of the engine cooled by the coolant components as much as possible to the heat storage to this recharge.

In addition to the component coolers shown and described, the cooling system may include other component coolers. This may be, for example, a transmission oil cooler, a cooler for an exhaust gas turbocharger, a charge air cooler and / or a cooler for exhaust gas recirculation.

LIST OF REFERENCE NUMBERS

10

internal combustion engine

12

cylinder crankcase

14

cylinder head

16

Main water cooler

18

Pump of the first cooling circuit

20

surge tank

22

Heater core

24

Pump of the second cooling circuit

26

Engine oil cooler

28

connecting element

30

casing

32

first flow space of the connection element

34

second flow space of the connection element

36

first outlet port of the first flow space

38

second outlet port of the first flow space

40

Inlet port of the first flow space

42

valve flap

44

check valves

46

first inlet port of the second flow space

48

second inlet port of the second flow space

50

Valve

52

first outlet port of the second flow space

54

second outlet port of the second flow space

56

third outlet port of the second flow space

58

Cooling channel of the cylinder head

60

Cooling channel of the cylinder crankcase

62

Cooling channel of the internal combustion engine

64

branch

Claims (11)

1. Combustion machine having a cooling system which has

   - a first cooling circuit, which comprises a surroundings heat exchanger in the form of a main water cooler and a first pump (18), and

   - a second cooling circuit, which comprises a second pump (24),
   wherein the cooling circuits are of integral form in at least one section, wherein a component cooler with

   - a first component cooler part, which comprises a cooler of a cylinder crankcase (12) of an internal combustion engine (10) of the combustion machine, and

   - a second component cooler part, which comprises a cooler of a cylinder head (14) of the internal combustion engine (10) and which is connected in parallel with respect to the first component cooler part,

   is arranged in the integral section of the cooling circuits, and
   wherein, in the cooling circuits, there is provided a coolant which is provided for being delivered by the pumps (18, 24), characterized in that the pumps that are integrated into different cooling circuits are designed to be regulable, and regulation of the volume flows of the coolant flowing through the component cooler and the surroundings heat exchanger is realized by way of adapted operation of the pumps (18, 24), wherein the volume flow through the first component cooler part is regulable by way of a pressure-controlled valve (50) in a manner dependent on the volume flow through the second component cooler part, such that a relevant flow of the coolant through the cooler of the cylinder crankcase occurs only when the flow through the cooler of the cylinder head has exceeded a defined threshold value.
2. Combustion machine according to Claim 1, characterized in that the pumps (18, 24) are driveable by electric motor.
3. Combustion machine according to one of the preceding claims, characterized by means for preventing a backflow of the coolant from the integral section into the cooling circuits.
4. Combustion machine according to one of the preceding claims, characterized by a heating heat exchanger (22) which is integrated into the second cooling circuit.
5. Combustion machine according to one of the preceding claims, characterized by a connecting section which connects the cooling circuits and which has a component cooler.
6. Combustion machine according to one of the preceding claims, characterized by an expansion tank (20) which is integrated into the first cooling circuit in parallel with respect to the surroundings heat exchanger.
7. Combustion machine according to one of the preceding claims, characterized by a connector element (28) with a housing (30) which forms at least two mutually separate flow chambers (32, 34), wherein

   - a first flow chamber (32) is connected to at least two inlet connectors (36, 38), which can be shut off by way of a device for preventing a backflow, and to an outlet connector (40), and

   - a second flow chamber (34) is connected to at least two inlet connectors (46, 48), of which at least one can be shut off by way of a pressure-actuated valve (50), and to at least two outlet connectors (52, 54).
8. Method for operating a combustion machine according to one of the preceding claims, characterized in that, in a warm-up phase of the combustion machine, only the second pump (24) of the second cooling circuit is operated.
9. Method according to Claim 8, characterized in that the second pump (24) of the second cooling circuit is operated with relatively low power in a first phase of the warm-up phase and is operated with relatively high power in a second phase of the warm-up phase.
10. Method for operating a combustion machine according to one of Claims 1 to 7, characterized in that the delivery power of the first pump (18) of the first cooling circuit is regulated on the basis of the temperature of the coolant at the outlet of the second component cooler part, and a volume flow through the first component cooler part is regulated by way of adapted operation of the second pump (24) of the second cooling circuit.
11. Method for operating a combustion machine according to Claim 6 or according to a claim dependent on Claim 6, characterized in that, during or after the filling of the cooling system with the coolant, the first pump (18) of the first cooling circuit part is operated, with an internal combustion engine (10) of the combustion machine not being operated.

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