DE102013224005A1 - cooling system - Google Patents

Abstract

A cooling system for an internal combustion engine comprising a first cooling circuit comprising a component cooler, an ambient heat exchanger, and a pump (18) and a second cooling circuit comprising a component cooler and a pump (24), the cooling circuits being integrally formed in at least one section and entering the cooling circuits is provided for conveying by the pump (18, 24) provided coolant, characterized in that the pumps are designed controllable and a control of the flowing through the component cooler volume flows of the coolant by means of an adapted operation of the pumps (18, 24).

Description

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

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 thermal energy is then in an ambient heat exchanger, the so-called main water cooler, as well as 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 motor vehicle ambient air delivered.

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 by means of a thermostatically controlled valve, the coolant is guided either over the large or the small cooling circuit. 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. Their delivery rate is thus basically 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. Attempts to reduce the fuel requirements of motor vehicles have therefore led to the development of mechanically driven coolant pumps which 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.

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 additional auxiliary heating device 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.

For a good and especially efficient cooling performance of a cooling circuit, it is relevant that this is vented as completely as possible. Accordingly, on the one hand during the filling process of the cooling circuit, in particular during a first filling or refilling as part of a maintenance, the air contained in the cooling circuit, which is displaced by the inflowing coolant, as completely dissipated. 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. A method for operating such a cooling system is the subject of claim 11. The subject of claim 15 is also a connection element that can be advantageously used to form the cooling system according to the invention. Advantageous embodiments and embodiments of the cooling system according to the invention and the method according to the invention are the subject 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 cooling power requirement 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 first cooling circuit comprising a component cooler, an ambient heat exchanger and a pump and a second cooling circuit comprising a component cooler and a pump, wherein the cooling circuits are integrally formed in at least a portion and provided in the cooling circuits a coolant for delivery is or is promoted according to the invention, characterized in that the pumps are designed to be controllable and a control of the flowing through the component cooler volume flows of the coolant by means of (mutually) adapted operation of the at least two pumps can take place or takes place.

The term "cooler" according to the invention heat exchangers understood that a heat transfer in both directions, i. from a component to the coolant and from the coolant to the component. The term "radiator" is chosen because during normal operation of the internal combustion engine, i. when this has reached its operating temperature range, a heat transfer from the component to the coolant is provided and the heat exchanger causes a 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.

In a preferred embodiment of the cooling system 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 a cooling system according to the invention can advantageously 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 at low Power is operated. The then a significant throttling effect having pump of the first cooling circuit largely prevents that a relevant volume flow of the coolant through the ambient heat exchanger, which may in particular be 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 not sufficient to prevent flow through the associated cooling circuit sufficiently, in a preferred embodiment of the cooling system according to the invention means for preventing backflow of the coolant from the integral 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, rapid heating of this component is achieved by only a very small flow of, in particular, an internal combustion engine and particularly preferably a cylinder head of the internal combustion engine, which is positive can affect 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 according to the invention, as usual in the prior art, has a surge tank, it can 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 as quickly as possible to be heated coolant is promoted to a relevant extent by the surge tank, which may otherwise be associated with a significant, undesirable in this phase of operation of the engine cooling of the coolant.

The inventive design of the cooling system 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 can be provided that during or after the filling of the cooling circuit with the coolant (not by the internal combustion engine and in particular electrically driven) pump of the first cooling circuit is operated without causing the internal combustion engine of the internal combustion engine is operated (non-operation of the internal combustion engine). This simplifies the filling process. On the other hand, in internal combustion engines with conventional cooling systems, the internal combustion engine usually has to be operated for venting after refilling or refilling the cooling system in order to operate the (main) pump of the cooling system, through which then the coolant and coolant contained in the cooling system Air is conveyed in the direction of the expansion tank.

In a further preferred embodiment of the cooling system according to the invention can be provided that a first of the component cooler is arranged in the integral portion of the two cooling circuits. In this case, the first component cooler particularly preferably comprises a first part-component cooler and a second part-component cooler, wherein the part-component coolers are connected in parallel. In particular, the first part-component radiator may be a cooler of a cylinder crankcase (in particular in the form of cooling channels integrated in the cylinder crankcase) and the second part-component radiator may be a cooler of a cylinder head (in particular in the form of cooling channels integrated in the cylinder head) of an internal combustion engine Internal combustion engine act.

It can be particularly preferably provided that the volume flow of the coolant through the first Teilkomponentenkühler by means of a pressure-controlled valve in dependence on the volume flow through the second Teilkomponentenkühler is controllable. Thus, it can be provided, in particular, 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 value.

By means of such a cooling system, a preferred embodiment of the method according to the invention can be realized in which the delivery 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 may 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 performance 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 of the control 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 opens or closes in a defined extent and thus the flow through the Radiator of the cylinder crankcase regulates.

An advantageously usable for the formation of such a cooling circuit 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 chambers 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.

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 number 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.

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

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

2 : a structural implementation of a part of the cooling system of 1 in a perspective view;

3 : in isolation, the connection element of the cooling system according to the 2 ;

4 FIG. 2: a schematic representation of a first flow space of the connection element according to FIG 3 ;

5 FIG. 2: a schematic diagram of a second flow space of the connection element according to FIG 3 ;

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

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

8th : the flow through the cooling system according to 1 in the first and second operating states of the warm operating internal combustion engine;

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

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

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

The 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 the internal combustion engine is shown. The internal combustion engine 10 can be designed as a conventional reciprocating internal combustion engine and then includes 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 from the top and further comprises at least one inlet and at least one exhaust valve for each of the cylinders, is controlled by the known manner, a gas exchange in combustion chambers formed by the cylinders and the piston.

Both the cylinder crankcase 12 as well as the cylinder head 14 are cooled by means of the cooling system, what these cooling channels 58 . 60 have, which are filled with the coolant of the cooling system and flows through this at least temporarily. The cooling channels 58 . 60 therefore provide radiator of the cylinder crankcase 12 as well as the cylinder head 14 dar. The (at least one) cooling channel 60 of the cylinder crankcase 12 and the (at least one) cooling channel 58 of the cylinder head 14 are formed to extend parallel and thus are also flowed through in parallel by the coolant.

The cooling system forms a first cooling circuit and a second cooling circuit, which in a section, namely in particular in that of the cooling channels 58 . 60 of the internal combustion engine 10 formed portion, are integrally formed. Accordingly, in the operation of the cooling system, the cooling channels 58 . 60 of the internal combustion engine 10 flows through at least partially, 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 serves as a so-called main water cooler 16 is provided, and a first, electrically driven and controllable in terms of their capacity pump 18 , which are downstream of the main water cooler 16 is arranged. Furthermore, a surge tank 20 provided in parallel with the main water cooler 16 integrated into 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 represents an ambient heat exchanger, with this 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 adjustable in terms of their capacity pump 24 located downstream of the heater core 22 is arranged. 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 , It goes, 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 expansion tank 20 from the first cooling circuit. The mouth of the connection section is downstream of the heater core 22 and upstream of the pump 24 (and thus also upstream of the internal combustion engine 10 ) integrated into the second cooling circuit. In the connecting portion of the intermediate cooling circuit is another component cooler in the form of an engine oil cooler 26 integrated. The engine oil cooler 26 is used in the operation of the internal combustion engine after reaching the operating temperature range of a cooling of the lubrication of the internal combustion engine 10 used engine oil.

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

As is clear from the 4 and 5 gives, is the first flow space 32 with two inlet connections 36 . 38 connected, of which a first, the inlet port 36 , as a supply of coolant from the first cooling circuit and the second, the inlet port 38 , Serves as a supply of coolant from the second cooling circuit. One with the first flow space 32 connected outlet port 40 is to a cooling channel 62 of the internal combustion engine 10 connected. This cooling channel 62 of the internal combustion engine 10 is upstream of a junction 64 provided, a division of the coolant to the parallel cooling channels 58 . 60 of the cylinder crankcase 12 as well as the cylinder head 14 serves. Within the first flow space 32 is still a valve flap 42 provided in dependence on the pressure difference of the first cooling circuit and the second cooling circuit in the first flow space 32 entering coolant in the direction of one or the other inlet port 36 . 38 is pivoted.

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

The second flow space 34 is also with two inlet connections 46 . 48 fluidly connected, wherein a first, the inlet port 46 , fluid-conducting with the cooling channel 28 of the cylinder crankcase 12 and the second, the inlet port 48 , fluid-conducting with the cooling channel 58 of the cylinder head 14 connected is. It is the with the cooling channel 60 of the cylinder crankcase 12 connected inlet connection 46 by means of a pressure-operated valve 50 closable. The valve 50 comprises a valve body, which by means of a prestressed spring element in the direction of an orifice opening of this inlet port 46 is charged. Furthermore, the second flow space 34 with three outlet connections 52 . 54 . 56 fluidly connected, 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 the discharge of coolant from the second flow space 34 in the second cooling circuit and the third, the outlet port 56 , for the discharge of 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 exclusively achieved by means of an adapted power control of the two pumps 18 . 24 reached.

The 6 and 7 show ways to control the cooling capacity of the cylinder crankcase 12 and the cylinder head 14 flowing through the flow of coolant. The pressure operated valve 50 in the second flow space 34 of the connection element 28 opens the one with the cooling channel 60 of the cylinder crankcase 12 connected inlet port 46 for example, only at a pressure difference of about 200 mbar. Such overpressure in the cooling channel 60 of the cylinder crankcase 12 can be achieved, for example, when the volume flow of the coolant through the cooling channel 58 of the cylinder head 14 at least 15 l / min. In the 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 by a combined operation of both pumps 18 . 24 can be achieved. It can be provided in particular that the greater part of the volume flow through the delivery rate of the pump 18 of the first cooling circuit is reached. But it may also be possible, the entire volume flow of the coolant through the cooling channel 58 of the cylinder head 14 solely by the operation of one of the two pumps 18 . 24 to reach. If, however, a volume flow through the cooling channel 58 of the cylinder head 14 exceeded 15 l / min, the pressure-operated valve opens 50 and thus allows that also the cooling channel 60 of the cylinder crankcase 12 is flowed through by the coolant. This volume flow of the coolant through the cooling channel 60 of the cylinder crankcase 12 in particular be smaller than the volume flow of the coolant through the cooling channel 58 of the cylinder head 14 , In the 7 is shown that the total volume flow through the internal combustion engine 10 in about half of each of the two pumps is generated. Any other division is by a corresponding control of the pump 18 . 24 possible.

In particular, it can be provided, a regulation of the pump 18 of the first cooling circuit as a function of the temperature of the cooling channel 58 of the cylinder head 14 Make escaping coolant. This is in the with the cooling channel 58 of the cylinder head 14 connected inlet port 48 of the connection element 28 a temperature sensor (not shown) integrated. Its measuring signal can be transmitted to a control device (not shown), for example a central engine control of the internal combustion engine, which in dependence on this measuring signal the pump 18 the first cooling circuit controls. The delivery rate of the pump 18 of the first cooling circuit can thus be continuously adjusted such that the out of the cooling channel 58 of the cylinder head 14 escaping coolant and thus the cylinder head 14 even in a defined operating temperature range. Whether at the same time the cylinder crankcase 12 - And if so, with what volume flow - is flowed through by the coolant and thus a cooling of the cylinder crankcase 12 should be done, then, for example, only by means of a corresponding, the regulation of the pump 18 of the first cooling circuit superimposed control of the pump 24 take place of the second cooling circuit. For this purpose, a temperature sensor (not shown) in the with the cooling channel 60 of the cylinder crankcase 12 connected inlet port 46 of the connection element 28 be provided, the measurement signal to a control device (not shown), in particular the engine control of the internal combustion engine, is transmitted, which then a corresponding control of the pump 24 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 8th clarifies once 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, 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 can be achieved. 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.

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 venting 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 , be used. By circulating the coolant, air that is still within the cooling system is taken along and gradually to the surge tank 20 promoted, in which it is separated from the coolant. Because both pumps 18 . 24 the cooling system are electrically driven and regulated, the circulation of the coolant in the cooling system without an operation of the internal combustion engine 10 respectively.

The 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 envisaged 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. Non-operation of the pump 18 the first cooling circuit in conjunction with the resulting closure of the first cooling circuit with the first flow space 32 of the connection element 28 connecting inlet connection 36 through the valve flap 42 (or the corresponding check valve 44 ) prevents operation of the pump 24 the second cooling circuit effectively a flow through the main water cooler 16 and the expansion 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. 9 ) may be provided, none of the pumps 18 . 24 to operate, whereby the coolant in the entire cooling system largely rests. This can be a particularly rapid heating of the cylinder head 14 and also the cylinder crankcase 12 due to the waste heat in the combustion chambers of the internal combustion engine 10 ongoing combustion processes can be achieved.

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

Once for the cylinder head 14 a defined minimum limit temperature has been reached, which is determined by measuring the temperature of the cooling passages of the cylinder head 14 leaking coolant can be determined, the third phase (see. 11 ) of the warm-up phase can be initiated, 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 reach 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 is the coolant in the cylinder head 14 in the engine oil cooler 26 delivered to the engine oil. Also in this phase can be provided that no flow through the cylinder crankcase 12 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 operated over a longer period of time with 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 with an operation of the pump 24 the second cooling circuit is combined 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 into the cooling system and in particular into the second cooling circuit and / or the intermediate cooling circuit, it may be provided after the operation of the internal combustion engine has ended (in particular if this has reached its operating temperature range during operation) the pumps 18 . 24 and especially the pump 24 the second cooling circuit to run for a defined period of time. This makes it possible to transfer the heat energy remaining in the coolant and in the operation of the internal combustion engine cooled by the coolant components as much as possible to the heat storage in order to recharge it.

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

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102010044167 A1 [0004, 0014]
• DE 10342935 A1 [0005, 0005, 0005]
• DE 19906523 A1 [0006]

Claims (15)

Cooling system for an internal combustion engine with a component cooler, an ambient heat exchanger and a pump ( 18 ) comprising a first cooling circuit and a component cooler and a pump ( 24 ), wherein the cooling circuits are integrally formed in at least a portion and in the cooling circuits for pumping through the pump ( 18 . 24 ) provided coolant is provided, characterized in that the pumps are designed controllable and a control of the flowing through the one or more component radiators volume flows of the coolant by means of an adapted operation of the pump ( 18 . 24 ) he follows. Cooling system according to claim 1, characterized in that the pumps ( 18 . 24 ) are driven by electric motor. Cooling system according to claim 1 or 2, characterized in that a component cooler is arranged in the integral section of the cooling circuits. Cooling system according to claim 3, characterized in that the component cooler comprises a first Teilkomponentenkühler and a second Teilkomponentenkühler, which are connected in parallel. Cooling system according to claim 4, characterized in that the volume flow through the first Teilkomponentenkühler means of a pressure-controlled valve ( 50 ) is controllable in dependence on the volume flow through the second Teilkomponentenkühler. Cooling system according to claim 4 or 5, characterized in that the first Teilkomponentenkühler a cooler of a cylinder crankcase ( 12 ) and the second Teilkomponentenkühler a cooler of a cylinder head ( 14 ) of an internal combustion engine ( 10 ) of the internal combustion engine.  Cooling system according to one of the preceding claims, characterized by means for preventing backflow of the coolant from the integral section into the cooling circuits. Cooling system according to one of the preceding claims, characterized by a heating heat exchanger integrated in the second cooling circuit ( 22 ).  Cooling system according to one of the preceding claims, characterized by a connecting portion connecting the cooling circuits with a component cooler. Cooling system according to one of the preceding claims, characterized by an expansion tank integrated in the first cooling circuit parallel to the ambient heat exchanger ( 20 ). Method for operating an internal combustion engine having a cooling system according to one of the preceding claims, characterized in that in a warm-up phase of the internal combustion engine only the pump ( 24 ) of the second cooling circuit is operated. A method according to claim 11, characterized in that in a first phase of the warm-up phase, the pump ( 24 ) is operated at a relatively low power and in a second phase of the warm-up phase with a relatively high power. Method for operating an internal combustion engine having a cooling system according to Claim 5 or Claim 5, characterized in that the delivery rate of the pump ( 18 ) of the first cooling circuit is controlled on the basis of the temperature of the coolant at the outlet of the second Teilkomponentenkühlers and a volume flow through the first Teilkomponentenkühler means of an adapted operation of the pump ( 24 ) of the second cooling circuit is controlled. Method for operating an internal combustion engine having a cooling system according to claim 10, characterized in that during or after filling of the cooling system with the coolant the pump ( 18 ) of the first partial cooling circuit in conjunction with a non-operation of an internal combustion engine ( 10 ) of the internal combustion engine is operated. Connection element ( 28 ) with at least two separate flow spaces ( 32 . 34 ) forming housing ( 30 ), wherein - a first flow space ( 32 ) with at least two inlet connections ( 36 . 38 ), which can be shut off by means of a device for preventing backflow, and an outlet port ( 40 ) and - a second flow space ( 34 ) with at least two inlet connections ( 46 . 48 ), at least one of which by means of a pressure-actuated valve ( 50 ) and at least two outlet ports ( 52 . 54 ) connected is.

Images