DE19908088A1 - Combustion engine, especially diesel engine, for vehicle with passenger compartment heater has exhaust gas heat exchanger between exhaust line and circulation medium circuit - Google Patents

Abstract

The engine (1) has an exhaust gas line (2), coolant line (5) forming a coolant circuit with a first pump (6), to which the engine is connected, and an exhaust gas heat exchanger (12) for transferring exhaust gas heat to a heating heat exchanger (15). The exhaust gas heat exchanger acts between the exhaust gas line and a circulation medium conductor (22) forming a circulation circuit to which the heating heat exchanger is connected either directly or indirectly.

Description

The invention relates to an internal combustion engine according to the preamble of Claim 1.

To improve the heating of the passenger compartment in motor vehicles, it is known to provide fuel-powered parking heaters or electric heaters. The disadvantage of these solutions is the high energy consumption, which must be taken into account is that these heaters until a warm operating state of the Internal combustion engine to be kept functional to provide a pleasant To ensure passenger compartment heating. It has already been suggested with an electric heating device the cooling water circuit or directly the heating air to heat a passenger compartment heater.

It has also been proposed to partially recover the amount of heat dissipated by the exhaust system of the vehicle as waste heat through an exhaust gas heat exchanger, which at least partially transfers the absorbed heat to the engine cooling circuit to shorten the warm-up phase and to support the heating. Such an internal combustion engine is described below with reference to the accompanying FIG. 1.

The internal combustion engine, generally designated 1 , has an exhaust gas pipe 2 starting from an internal combustion engine 1 a, which extends away from the housing 3 of the internal combustion engine 1 and in which the exhaust gases of the internal combustion engine are discharged from the internal combustion engine 1 in the flow direction indicated by the arrow 4 . The internal combustion engine 1 is in particular a diesel internal combustion engine, preferably a DI diesel internal combustion engine. Further components and functional parts of the internal combustion engine 1 are a coolant line 5 flowing through the internal combustion engine 1 a, which forms a cooling circuit 8 with a first coolant pump 6 arranged therein and a cooler 7 also arranged therein, the cooler 7 in a first parallel section 5 a Coolant line 5 surrounding second parallel section 5 b is arranged, the flow passages are regulated by a thermostat 9 , which is arranged in the connection area of the parallel sections 5 a, 5 b. The thermostat 9 closes the parallel section 5 b when the coolant temperature is less than 95 ° C, and it opens the parallel section 5 b when the coolant temperature rises above 95 ° C. The cooler 7 is thus directly involved in this temperature range. An expansion tank 11 a is arranged in a parallel line section 11 connecting the coolant line 5 to the cooler 7 .

An exhaust gas heat exchanger 12 is arranged between the exhaust gas line 2 and the coolant line 5 , which permits heat exchange between these two lines or the media contained therein. Furthermore, in the coolant line 5, an oil cooler 13 and in a bypass 14 circumventing this, a heating heat exchanger 15 is arranged, which emits heat to a passenger compartment 16 , not shown in detail, and is a directly or indirectly effective part of the passenger compartment heater 16 a.

In the coolant line 5 , a second coolant pump 17 is arranged, which is preferably electrically driven and in the present embodiment in the flow direction according to arrow 18 downstream of the exhaust gas heat exchanger 12 so that the cooling medium, for. B. cooling water, first to the pump 17 and then to the exhaust gas heat exchanger 12 . The second coolant pump 17 can be supplied with drive energy by an electrical control device (not shown). With 19 a catalyst in the exhaust pipe 2 is designated.

In the functional operation of this arrangement, considerable amounts of energy are dissipated as heat losses via the exhaust line 2 during the warm-up phase. These losses are at least partially transmitted through the exhaust gas heat exchanger 12 to the cooling circuit 8 to shorten the warm-up phase and to support the passenger compartment heater 16 a. It is particularly disadvantageous in the case of direct-injection diesel internal combustion engines that, due to the low consumption and the heavy internal combustion engine, the energy transferred from the exhaust gas to the coolant only contributes to a slight acceleration of the warm-up phase and, as a result, only slightly better heating outputs. Furthermore, in the event of leaks in the exhaust gas heat exchanger 12, the loss of the entire coolant and thus damage to the internal combustion engine 1 are likely.

The invention is based, firstly, the operational safety of the task To enlarge internal combustion engine and on the other hand to find a configuration that enables an improved temperature-mass flow ratio.

This object is solved by the features of claim 1. Beneficial Developments of the inventions are the subject of the dependent claims.

In the embodiment according to the invention, an additional circulation circuit with a circulation line is provided, and the exhaust gas heat exchanger 12 is also effective between the exhaust line and the supply line, with a cooling heat exchanger which is effective between the circulation line and the coolant line.

By decoupling the exhaust gas heat exchanger from the engine cooling circuit is not only increases operational safety. By arranging a circulation circuit the amount of circulation medium is decoupled from the flow of the engine coolant pump and an optimal temperature-mass flow ratio can be set.

This setting can be determined by a default setting or by a setting taking into account the respective functional criteria in the functional mode. With decreasing flow rates, the coolant heating in the exhaust gas heat exchanger increases. Only when the flow rates are very small does the transferred energy drop significantly as a product of the circulating mass flow, the specific heat capacity and the temperature rise. After simulations and experimental tests, a delivery rate of approx. 200 kg / h is ideal for a 1200 kg vehicle, namely a passenger car with a 1.9 l 66 kW TDI engine. For other vehicle concepts, these values can deviate upwards or downwards. In principle, however, the circulation mass flow should also be significantly lower than the flow of the motor pump 6 of the coolant circuit 8 , even in the case of highly motorized, heavy passenger cars.

It is therefore advantageous to assign a pump to the circulation circuit Flow is adjustable and in through the existing electrical control device Dependence on functional criteria of the internal combustion engine and / or the vehicle and / or the passenger compartment heating device is adjustable. This also applies to the Coolant circulation quantity in the area of the cooling heat exchanger. That's why it is also advantageous in this regard, the cooling heat exchanger in a parallel section to arrange the coolant circuit, which has its own, in particular electrically  driven pump is assigned, the flow rate taking into account the the aforementioned functional criteria can be set by the control device.

The heating power of the passenger compartment heater is particularly in the Warm-up phase of the internal combustion engine depending on its heat capacity and thermal inertia. This limits the effectiveness of the heating device.

The invention is further based on the object in an internal combustion engine according to the preamble of claim 11 the dependency of the passenger compartment Heater on the heat capacity and thermal inertia of the Reduce internal combustion engine.

This object is solved by the features of claim 11. At this The internal combustion engine is connected to one of the coolant lines branching first bypass is connected in which a first thermostatic valve is arranged, the first bypass until reaching a medium Largely blocks the coolant temperature and opens above this coolant temperature, and that in a second bypass extending parallel to the first bypass second thermostatic valve is arranged, the second bypass above the middle Coolant temperature largely blocks. As a result, the internal combustion engine largely decoupled from the cooling circuit, especially in the warm-up phase, and the latter and / or a circulation circuit and an associated heating Heat exchangers can be Heat exchange to be heated up quickly.

Since the temperatures of exhaust gases from an internal combustion engine in operation Evaporation point of a liquid medium in heat exchange with them, especially cooling water, there is a risk of damage of the circuit in heat exchange.

The invention is further based on the object of an internal combustion engine the preamble of claim 14 so that an overheating of the the exhaust gas in the heat exchange medium is avoided.

This object is solved by the features of claim 14. At this In an embodiment, the exhaust pipe has a bypassing the exhaust gas heat exchanger Bypass, whereby the flow passage through the bypass through a  Control device or regulating device with increasing exhaust gas temperature or Circulation medium temperature is opened. This makes it possible to control the exhaust gases and the to distribute the amount of heat it contains in such a way that the Heat exchanger flowing amount no heat damage in the area Can cause heat exchanger circuit.

It is also advantageous to use a catalytic heater for the exhaust gas heat exchanger to arrange.

Advantageous exemplary embodiments of the invention are described below with reference to simplified drawings explained in more detail. Show it

Fig. 2 shows an internal combustion engine according to the invention in a schematic representation;

Figure 3 is an internal combustion engine according to the invention in a schematic representation in a modified configuration.

Figure 4 is an internal combustion engine according to the invention in a schematic representation in a further modified embodiment.

Figure 5 is an internal combustion engine according to the invention in a schematic representation in a further modified embodiment.

6 shows an inventive exhaust gas heat exchanger for an internal combustion engine in section and in an enlarged view.

Figure 7 is an exhaust pipe of the internal combustion engine with a Katalytheizer in axial section.

Fig. 8 is the Katalytheizer in a modified configuration;

Fig. 9 shows the section IX-IX in Fig. 8;

Fig. 10 is a diagram showing the temperature profiles in test runs with and without the use of exhaust gas heat.

The configurations according to the invention which are yet to be described are further developments of the internal combustion engine according to FIG. 1, and therefore only the supplementary features are shown and described with reference to the drawing according to FIG. 1 and the associated description, identical or comparable parts being provided with the same reference symbols .

In the embodiment of FIG. 2, a separate circulation circuit is provided with a circumferential circulation of fluid line 22 is provided 21, wherein the exhaust gas heat exchanger 12 is arranged between the exhaust line 2 and the means of circulation line 22 and is able to conduct heat between the two lines. In addition, a cooling heat exchanger 23 is provided between the circulation medium line 22 and the cooling circuit 8 , which is preferably arranged in the parallel section 5 c of the coolant line 5 , to which the second coolant pump 17 is assigned in particular, and preferably in a position upstream of the cooling heat exchanger 23 , so that the coolant first reaches the coolant pump 17 and then the cooling heat exchanger 23 . The parallel sections 5 d, 5 e which contain the heating heat exchanger 15 and the oil cooler 13 branch off in the flow direction behind the cooling heat exchanger 23 from the parallel section 5 c. A separate circulation pump 24 is assigned to the circulation circuit 21 , which is preferably electrically driven and the delivery volume of which can preferably be increased and decreased. For this purpose, the circulation pump 24 is connected to the electrical control device by means of energy and control lines (not shown) and can be controlled with regard to its operating time and delivery quantity taking into account functional parameters of the internal combustion engine and / or the catalytic converter 19 and / or the passenger compartment heating device 16 a. These control function features also apply to the second coolant pump 17 .

In the embodiment according Fig. 3, an exhaust gas heat exchanger 12 is omitted, and therefore no heat can be of the exhaust pipe 2 to the coolant circuit 8 transmitted. In this embodiment, the coolant circuit 8 has two thermostatic valves 25 , 26 with different opening temperatures, each of which has a free outlet and a throttled outlet in the form of parallel lines 25 a, 25 b, 26 a, 26 b. The coolant flow conveyed by the pump 6 is divided and flows through a bypass 27 passing through the internal combustion engine 1 a and through a bypass 28 extending parallel thereto, the thermostatic valve 25 being arranged in the bypass 26 in the flow direction behind the internal combustion engine 1 a and the thermostatic valve 26 is arranged in the bypass 28 . Until a coolant temperature of approximately 65 ° C. is reached, the thermostatic valve 25 largely blocks the flow through the internal combustion engine 1 a, while the bypass 28 is fully open. Approx. 1% of the coolant flow through the internal combustion engine 1 a, while the rest flows through the bypass 28 . At about 65 ° C coolant temperature, the thermostatic valve opens the unthrottled parallel line 25 a, so that about half of the coolant flow through the internal combustion engine 1 a and the bypass 28 flow. At approximately 95 ° C. coolant temperature, the bypass 28 is largely blocked by switching the thermostatic valve 26 , so that approximately 99% of the coolant flow now flows through the internal combustion engine 1 a. Both the switching thresholds and the distribution of the coolant flows can be carried out differently than suggested here, without questioning the basic advantages of the system. Fig. 3 shows the system with passive control with thermostats.

Within the scope of the invention, a further bypass 29 that bypasses the internal combustion engine 1 a can be provided, which extends between the sections of the bypass 27 that lead to the internal combustion engine 1 a and is connected to the supplying section before the first thermostatic valve 25 . In this bypass 29 , a coolant pump 31 can be provided, the purpose of which is to maintain a circuit flow in the internal combustion engine 1 a and thereby avoid overheating in partial areas.

With only heat transfer from the exhaust gas through the circulation circuit 21 to the coolant, optimal support of the passenger compartment heater 16 a cannot be guaranteed in an embodiment according to FIG. 2 because of the high flow rate in the cooling circuit 8 , since the coolant in the engine cooling circuit 8 when flowing through the exhaust gas heat exchanger 12 is only slightly heated. An arrangement of a further heating heat exchanger according to FIG. 4 or the connection of the heating heat exchanger 15 to the circulation circuit 21 and the absence of energy delivery to the engine cooling system (not shown) is more favorable. Both configurations show significant increases in heating output, the configuration with two heating heat exchangers 15 , 15 a being more efficient because of the overall higher energy supply and the enlarged heat exchanger area. In FIG. 4, the second heating heat exchanger 15 a in the means of circulation pipe 22 in combination with the first heating heat exchanger 15 is arranged. However, it can also be formed independently of the first heating heat exchanger 15 as an individual part and z. B. be arranged at a distance from it.

Since the heat output from the circulation circuit 21 to the passenger heater 16 a, z. B. to the heating air, at high engine loads is clearly below the amount of heat extracted from the exhaust gas, there is a risk that the boiling temperature in the circulation circuit 21 will be exceeded and the heat transfer system will be damaged if the journey takes longer or the heater 16 is switched off. The heat output to the circulation circuit 21 can be limited by partially or completely bypassing the exhaust gas heat exchanger 12 . For this purpose, a bypass 2 a bypassing the exhaust gas heat exchanger 12 can be provided, which is brought back together with the exhaust pipe 2 in the flow direction behind the heat exchanger 12 or can be continued in parallel as an exhaust switch. The exhaust gas heat exchanger 12 can be partially or completely decoupled from the exhaust gas flow by means of the bypass 2 a. As shown in FIG. 4, the circulation circuit temperature can be set in a targeted manner by a control or regulating device 33 , e.g. B. depending on the temperature of the circulation medium or the exhaust gas. Thermostat control with a temperature sensor 34 and a control valve 36 connected to the latter by a control line 35 is proposed. B. at a temperature of 105 ° C in the circulation medium, the path through the exhaust gas heat exchanger 12 opens continuously and allows heat to be transferred to the circulation circuit 21 and further to the or the heat exchanger 15 , 15 a. In the embodiment shown in Fig. 4, the control valve 36 is arranged in the branch of the bypass 2 a.

In the embodiment according to FIG. 5, an additional heat exchanger 37 is provided between the circulation circuit 21 and the cooling circuit 8 , which enables direct heat transfer from the circulation medium to the coolant. This heat exchanger 37 can be arranged in the parallel line 5 c, preferably in the flow direction in front of the parallel lines 5 d, 5 e. The second coolant pump 17 can be arranged upstream of the additional heat exchanger 37 , as shown in FIG. 5.

Furthermore, a bypass 20 a in the circulation circuit 21 can be assigned to the additional heat exchanger 37 , wherein the flow passage can be regulated depending on the temperature of the circulation medium, for. B. by a thermostatic valve 38 , the bypass 22 a below a certain circulation medium temperature, for. B. opens about 105 ° C, wherein the through the heat exchanger 37 parallel section 22 b is closed or partially open, and when the above-mentioned circulation medium temperature is exceeded, the parallel section 22 b opens and the bypass 22 a closes or partially opens. This can prevent the cooling circuit 8 from being transferred to an excessively high temperature.

In the exemplary embodiment according to FIG. 6, a modified control or regulating device 33 a is provided, which in the present exemplary embodiment can be integrated into the exhaust line 2 with an exhaust gas heat exchanger 12 a of special construction. In this embodiment, the flow passage through the bypass 2 a is not increased or decreased depending on the temperature of the circulation medium, as is the case in the embodiment according to FIG. 4, but the flow passage through the bypass 2 a is dependent on the temperature in the Exhaust gas controlled or regulated so that the exhaust gas flow through the bypass 2 a at high exhaust gas temperatures and the exhaust gas flow through the exhaust gas heat exchanger 12 at low exhaust gas temperatures, the control or regulation can be carried out continuously, that is, with increasing exhaust gas temperature, the flow passage through the Bypass 2 a enlarged and reduced with falling exhaust gas temperature.

In the embodiment of Fig. 6 is a mechanical control device 33 a is provided. The exhaust gas heat exchanger 12 a is arranged in the free flow cross section of the exhaust pipe 2 and z. B. formed by a block 41 having a first axial or axially parallel flow channel 2, which forms in the region of the exhaust gas heat exchanger 12, the actual exhaust pipe 2 and a second axial or axially parallel flow channel 2 a which is a non umspültes by the coolant exhaust pipe and forms the bypass 2 a. This non-washing can, for. For example, be realized in that the exhaust pipe 2 is contained in a block 41 by a coolant block part 41 isolated a, z. B. is separated by a cavity 41 b. The block 41 a containing the coolant is through the exhaust line 2 radially penetrating line sections 41 c, 41 d directly to the cooling circuit 8 according to FIG. 1 or to the circulation circuit 21 according to FIG. 2 or 4 or directly to the circulation circuit 21 according to FIG. 5 connected. FIG. 5 shows a bypass 2 a according to FIG. 6 in a schematic representation.

Each flow channel 2 , 2 a is assigned a control valve 42 , 43 , each with a closure body 42 a, 43 a, which is axially movable with respect to the associated flow channel 2 , 2 a and by an element that moves depending on the exhaust gas temperature , is movable between an open position and a closed position. Such an element can advantageously be formed by a valve stem 42 b, 43 b holding and moving the associated closure body 42 a, 43 a, which consists of bimetal and forms a switching arm. With reference to FIG. 6 it can be explained that it is a schematic diagram in which the situation for a high exhaust gas temperature with high exhaust gas mass flow in the upper area A of the illustration and in the lower area B of the illustration which is separated from the upper area by a center line 44 is the functional state is shown at low exhaust gas temperature and low exhaust gas mass flow. In the latter case B (bottom), the exhaust gas mass flow in the exhaust gas heat exchanger 12 a is low or blocked, and in the former case A (top) is more or less open depending on the level of the exhaust gas temperature. As a result, the heat exchanger circuit 46 is protected against overheating, which is particularly important when the passenger compartment heater 16 a is switched off. The valve stems 42 b, 43 b can be attached to the block 41 or to the pipe wall of the exhaust pipe 2 , as is indicated in FIG. 6. The circuit 46 can be the cooling circuit 8 or the circulation circuit 21 .

However, the Fig. 6 can also be understood so that the block 41 each have two flow channels 2, a has 2 with associated control valves 42, 43.

Since in this embodiment a heat discharge from the circulation circuit 21 is possible even when switched heater 16 of the cooling circuit 8, may be obtained at least partial decoupling of the exhaust gas heat exchanger 12 by an at least partial opening of the bypass 2 a larger leakage currents and several kW " Leakage energy "are tolerated. This enables the use of simple and inexpensive controls that are controlled by the exhaust gas temperature, e.g. B. have bimetallic shift arms that control the exhaust gas flow passage through the exhaust pipe 2 and / or the bypass 2 a, as the embodiment of FIG. 6 shows. For safety reasons, the heat exchanger is preferably regulated on the input side via closure elements that close at high temperatures, while the bypass or passages 2 a are controlled by closure elements arranged on the output side. This has the advantage that when a defect of the switching arms or the flow channels 2 and bypasses 2 a open automatically due to the flow pressure, the closing body 42 a, 43 a dodge and overheating of the heat exchanger circuit or the cooling circuit is prevented. 8 In addition, in the case of a large flow passage, the closure body or bodies of the parallel sections 2 are forcedly closed or sealed, specifically because of the pressurization of the closure bodies 42 a, 43 a.

The switchover temperature in the exemplary embodiments according to FIG. 6 can be, for example, 400 ° C. Other switchover temperature values are entirely possible depending on the heat requirement and the design of the overall system. The closing temperature of the valve or closure body 42 a, 43 a should be slightly above the opening temperature of the closure body 42 a, 43 a in order to prevent a complete closure of the exhaust pipe 2 .

By expanding the exhaust system or the internal combustion engine with a catalytic converter 19, which is preferably designed and functioning as an oxidation catalytic converter, as a catalytic heater, namely a catalytic heater 44 according to FIG. 7, heat deficits can be compensated for after a cold start. The Katalytheizer 44 consists essentially of an electrically heatable catalytic converter, hereinafter called E-Cat 19 a, and a fuel injection device 45, 19 a can be injected with the fuel upstream of the E-catalysts into the exhaust pipe. 2 To generate heat, the E-Cat 19 a is connected to an electrical circuit 46 , which can be done by the existing electrical control device (not shown), and heated to temperatures well above the light-off temperature. The fuel then injected into the exhaust system is catalytically converted to CO ₂ and H ₂ O with the residual oxygen in the exhaust gas with the development of heat. Depending on the exhaust gas mass flow and the amount of fuel injected, the electricity for E-cat heating can be switched off if the catalyst is sufficiently warmed, since the reaction then continues alone.

To protect the vehicle electrical system, however, the use of a low-power E-Cat 19 a with current consumption of 50 A is recommended. Since such a performance extinction of the catalytic conversion by "blowing out" of the E-cat is not exclude a 19, as shown in FIG. Are designated 8 in the same or similar parts the same reference numerals, proposed that the E-Cat 19 a, to be smaller than the downstream catalytic converter 19 so that only part of the exhaust gas mass flow flows through the E-cat 19 a and the risk of blow-out is prevented. It is advantageous for the carrier tube 19 b of the E-Kats 19 a by the dimension a upstream via the E-Cat 19 to leave a sufficient addition. This prevents part of the fuel, preferably injected in the form of a fuel-air mixture, such as a fuel mist, from passing the E-Cat 19 a directly into the support cat 19 . In the case of an eccentric arrangement, in particular in the peripheral position as shown in FIG. 8, the electrical power lines of the electrical circuit 53 can be laid without great temperature stress if they are arranged on the side to which the E-Cat 19 a is offset and preferably abuts the inner wall of the exhaust pipe 2 . However, a central arrangement is also conceivable, especially if the electrical lines of the circuit 46 are temperature-resistant, for. B. are insulated accordingly heat protected.

The oxidation properties of the catalytic surface are improved by the E-cat operation and the catalytic heating, so that an emission reduction can be expected with HC, CO and particle fractions in the exhaust gas. On the one hand, there is an increase in NOx emissions due to the higher engine load due to the E-Cat 19 a upstream. On the other hand, some of the raw NOx emissions are reduced with the injected fuel hydrocarbons, so that a slight reduction in NOx can also be expected in the overall balance.

However, continuous exhaust gas heating with, for example, 4 kW does not only lead to a considerable increase in fuel consumption. After heating of the circulation circuit 21 of the path whereby the heat output of the heating heat exchanger is increased 15 opens to the auxiliary heat exchanger 37 and most of the heat generated in Katalytheizer 44 is discharged into the engine cooling circuit 8, when the achievable fuel saving and Increase in heating power is low. After the circulation circuit has been heated up once with the highest possible additional heating output to, for example, approximately 90 ° C., the catalytic heater 44 can be switched off again, since the exhaust gas energy is then sufficient to support the interior heating. With a heating power of 6 kW in a test on a mid-range car, the operating time in the MVEG cycle was about 75 seconds at an ambient temperature of + 20 ° C and about 155 seconds at an ambient temperature of -20 ° C. Fig. 10 shows the Heizluft- temperature curve of the test vehicle, and a simulation of the Katalytheizers 44 with the described operation strategy. In the diagram shown in FIG. 10, all features are self-explanatory and recognizable, so that no further description is required. The dashed curve I represents the speed in km / h, the solid curve II a measurement without the use of exhaust gas heat and the bold curve III shows a simulation of the use of exhaust gas heat plus a catalytic heater (curve IV) with 6 KW for 75 seconds Advantages of the process can be seen.

At + 20 ° C start temperature in the MVEG cycle with an additional consumption of 3% be counted. Conventional parking heaters with the same heating output even with generally cheaper air heaters with <15% more consumption in the MVEG Cycle.  

REFERENCE SIGN LIST

1

Internal combustion engine

1

a internal combustion engine

2nd

Exhaust pipe

2nd

a bypass

3rd

casing

4th

Arrow (flow direction)

5

Coolant line

5

a parallel section

5

b parallel section

5

d parallel section

5

e parallel section

6

Coolant pump

7

cooler

8th

Cooling circuit

9

Thermostat controller

10th

11

Line section

11

a Expansion tank

12th

Exhaust gas heat exchanger

12th

a Exhaust gas heat exchanger

13

oil cooler

14

bypass

15

Heating heat exchanger

15

a heat exchanger

16

Passenger compartment

16

a Passenger compartment heater

17th

Coolant pump

18th

Arrow (flow direction)

19th

catalyst

19th

a E-cat

19th

b support tube

20th

21

Circulation cycle

22

Circulation line

22

a bypass

22

b parallel section

23

Cooling heat exchanger

24th

Circulation pump

25th

Thermostatic valve

25th

a parallel line

25th

b Parallel line

26

Thermostatic valve

26

a parallel line

26

b Parallel line

27

bypass

28

bypass

29

bypass

30th

31

Auxiliary pump

32

33

Control or regulating device

33

a mechanical control device

34

Temperature sensor

35

Signal line

36

Control valve

37

Additional heat exchanger

38

Thermostatic valve

39

40

41

block

41

a block part

41

b cavity

41

c line section

41

d line section

42

Control valve

42

a closure body

42

b valve stem

43

Control valve

43

a closure body

43

b valve stem

44

Catalytic heater

45

Fuel injection device

46

electrical circuit

Claims (20)

1. Internal combustion engine ( 1 ), in particular diesel internal combustion engine, for a vehicle, with a passenger compartment heater ( 16 a), an exhaust pipe ( 2 ), a coolant line ( 5 ), the cooling circuit ( 8 ) with a first pump ( 6 ), to which the internal combustion engine ( 1 ) is connected, and an exhaust gas heat exchanger ( 12 ) for transferring exhaust gas heat to a heating heat exchanger ( 15 ), characterized in that the exhaust gas heat exchanger ( 12 ) between the exhaust gas line ( 2 ) and a circulation medium line ( 22 ) is effective, which forms a circulation circuit ( 21 ) to which the heating heat exchanger ( 15 ) indirectly ( Fig. 2) or directly ( Fig. 4 and 5) is connected. 2. Internal combustion engine according to claim 1, characterized in that a particularly electrically driven pump ( 17 ) is arranged in the circulation circuit ( 21 ). 3. Internal combustion engine according to claim 1 or 2, characterized in that a cooling heat exchanger ( 23 ) between the circulation medium line ( 22 ) and the coolant line ( 5 ) is arranged. 4. Internal combustion engine according to claim 3, characterized in that the cooling heat exchanger ( 23 ) in a parallel section ( 5 c) of the coolant line ( 5 ) is arranged. 5. Internal combustion engine according to claim 4, characterized in that in the parallel section ( 5 c) a second, preferably electrically operated pump ( 31 ) is arranged. 6. Internal combustion engine according to claim 4 or 5, characterized in that the cooling heat exchanger ( 23 ) is associated with a thermostatic valve ( 38 ) that the flow passage through the cooling heat exchanger ( 23 ) above a temperature of about 95 to 105 ° C in Circulation means blocks ( Fig. 5). 7. Internal combustion engine according to one of claims 2 to 6, characterized in that the delivery volume of the pump ( 17 ) in the circulation circuit ( 21 ) and / or the delivery volume of the pump ( 31 ) in the parallel section ( 5 c) is or are variable and in each case A regulating device is provided for regulating the delivery volume as a function of the operating parameters of the internal combustion engine and / or its exhaust system or catalyst ( 19 ) and / or the cooling circuit ( 8 ). 8. Internal combustion engine according to one of the preceding claims, characterized in that the circulation medium line ( 21 ) with a heating heat exchanger ( 15 a) is connected ( Fig. 4). 9. Internal combustion engine according to one of the preceding claims 4 to 8, characterized in that a heating heat exchanger ( 15 ) is arranged in the coolant line parallel section ( 5 c). 10. Internal combustion engine according to one of the preceding claims, characterized in that the internal combustion engine ( 1 ) to a from the coolant line ( 5 ) branching first bypass ( 27 ) is connected, in which a first thermostatic valve ( 25 ) is arranged, which is the first bypass ( 27 ) largely blocks until an average coolant temperature is reached and opens above this coolant temperature, and that a second thermostatic valve ( 26 ) is arranged in a second bypass ( 28 ) which extends parallel to the first bypass ( 27 ) and which connects the second bypass ( 28 ) largely blocks above the average coolant temperature. 11. Internal combustion engine ( 1 ), in particular diesel internal combustion engine, for a vehicle, with a passenger compartment heating device ( 16 a), an exhaust gas line ( 2 ), a coolant line ( 5 ), which has a cooling circuit ( 8 ) with a first pump ( 6 ), to which the internal combustion engine ( 1 ) is connected, and an exhaust gas heat exchanger ( 12 ) for transferring exhaust gas heat to a consumer, or internal combustion engine ( 1 ) according to one of the preceding claims, characterized in that the internal combustion engine ( 1 ) a from the coolant line ( 5 ) branching first bypass ( 27 ) is connected, in which a first thermostatic valve ( 25 ) is arranged, which largely blocks the first bypass ( 27 ) until a medium coolant temperature is reached and opens above this coolant temperature, and that In a second bypass ( 28 ) extending parallel to the first bypass ( 27 ), a second thermostatic valve ( 26 ) is arranged, the second it bypass ( 28 ) largely blocks above the mean coolant temperature. 12. Internal combustion engine according to claim 10 or 11, characterized in that the average coolant temperature is about 65 ° C and preferably the response temperature of the second thermostatic valve ( 26 ) is higher than the average coolant temperature, in particular about 95 ° C. 13. Internal combustion engine according to one of claims 10 to 12, characterized in that the thermostatic valves ( 25 , 26 ) each have a free and a throttled output ( 25 a, 25 b; 26 a, 26 b). 14. Internal combustion engine ( 1 ), in particular a diesel internal combustion engine, for a vehicle, with a passenger compartment heater ( 16 a), an exhaust pipe ( 2 ), a coolant line ( 5 ), which has a cooling circuit ( 8 ) with a first pump ( 6 ), to which the internal combustion engine ( 1 ) is connected, and an exhaust gas heat exchanger ( 12 ) for transferring exhaust gas heat to a consumer, or internal combustion engine ( 1 ) according to one of the preceding claims, characterized in that the exhaust pipe ( 2 ) a the exhaust gas heat exchanger ( 12 , 12 a) has a bypass ( 2 a) and the flow passage through the bypass ( 2 a) is opened by a control device ( FIG. 6) or regulating device ( 33 , FIG. 4) with increasing exhaust gas temperature or circulation medium temperature becomes. 15. Internal combustion engine according to claim 14, characterized in that the exhaust gas heat exchanger (12 a) is integrated into the exhaust pipe (2) and at least one first flow passage (2), which is bathed by the coolant or the circulation means, and at least one further flow passage ( 2 a), which is not flushed with the coolant or the circulation medium, and the flow passages ( 2 , 2 a) are each controlled by a valve ( 42 ) depending on the temperature of the exhaust gases. 16. Internal combustion engine according to claim 14 or 15, characterized in that the valves ( 42 , 43 ) are controlled by bimetallic parts. 17. Internal combustion engine according to one of the preceding claims, characterized in that a catalytic converter ( 19 ), in particular an oxidation catalytic converter, is arranged in the exhaust line ( 2 ). 18. Internal combustion engine according to claim 17, characterized in that the catalyst ( 19 ) by an electrically operated E-Kat ( 19 a) forced catalyst heater ( 44 ). 19. Internal combustion engine according to claim 18, characterized in that the E-Kat ( 19 a) is preceded by a fuel injection device ( 45 ). 20. Internal combustion engine according to claim 18, characterized in that the E-cat ( 19 a) and the fuel injection device ( 45 ) are dimensioned smaller in cross-sectional dimension than the catalyst ( 19 ) and are arranged offset to the peripheral wall of the catalyst housing.