DE102007054197A1 - Drive system for vehicle, has internal combustion engine, exhaust gas cleaning device and generator for feeding electrical on-board network of vehicle, where heat engine is energized with heat energy of internal combustion engine - Google Patents

Abstract

The drive system (16) has an internal combustion engine (17), an exhaust gas cleaning device and a generator (19) for feeding an electrical on-board network of vehicle. A heat engine (1) is energized with heat energy of the internal combustion engine or a self-sufficient heat energy source of the vehicle. The heat engine is formed for powering the generator or for heating-up the exhaust gas cleaning device.

Description

The The present invention relates to a drive system for a vehicle with internal combustion engine and exhaust gas purification device and a Generator for supplying an electrical voltage system of the Vehicle according to the preamble of claim 1.

at a large part known motor vehicles are internal combustion engines to drive used, be it now as the sole drive source or in conjunction with an electric motor, as is the case with hybrid vehicles. The internal combustion engine generates hot exhaust gas, which is usually relaxed in the environment. In this process becomes energy dissipates that for the further use in the system motor vehicle then no longer Available.

Around now to use the residual energy contained in the exhaust gas, it is after a attributed to the applicant Procedure already known, with the contained in the exhaust stream Residual energy to vaporize water and relax the vapor phase and with the mechanical energy thus gained, in turn, the crankshaft to pressurize the internal combustion engine.

Even though this is quite an approach that contained in the exhaust gas Heat on To use this, a feedwater pump is required to the system the liquid Phase to feed and above In addition, to achieve a high thermal efficiency a reheat required, which leads to a corresponding space requirement.

emission control systems for internal combustion engines usually need a predetermined reaction temperature to a proper conversion rate to achieve and therefore work with a lower efficiency, as long as the exhaust gas purification plant their predetermined reaction temperature has not reached yet. In hybrid vehicles, one on the vehicle provided on-board voltage network due to the energy needs of or Electric motors stronger loaded, as in vehicles without the support of such Electric motors is the case.

outgoing It is the object of the present invention to provide a drive system for to create a vehicle in which the of the internal combustion engine originating thermal energy can be used to feed the on-board voltage network and in addition, the rate of implementation of the exhaust gas purification device is increased immediately after the start of the internal combustion engine.

The Invention now provides for the solution of this Task, a drive system with the features of claim 1. Advantageous Embodiments thereof are described in the further claims.

To The invention provides a drive system for a vehicle with internal combustion engine and exhaust gas purification device and a Generator for supplying an electrical voltage system of the Vehicle, which by means of heat energy of the internal combustion engine and / or a self-sufficient heat energy source the vehicle powered heat engine owns that for driving the generator and / or for heating the exhaust device is formed.

In order to The invention provides a drive system in which the heat energy the internal combustion engine, usually over the Exhaust system of the internal combustion engine is dissipated into the environment, to is used, a heat engine to drive, in turn, the generator for feeding the on-board voltage network of the vehicle drives.

In addition to Thermal energy the internal combustion engine or even instead one can on the vehicle provided independently working heat energy source the heat engine driving, in turn, the generator for feeding the on-board voltage network drives and / or heats the exhaust gas purification device, so that this is their intended operating temperature even immediately after the start of the internal combustion engine has, before the heat energy contained in the exhaust gas of the internal combustion engine would be able to the exhaust gas purification device to the intended operating temperature heat.

at the heat energy source it may be independent of the internal combustion engine device, such as one for providing mechanical energy intended unit whose waste heat the heat engine so energized that it drives the generator and / or the exhaust purification device can heat up.

These Thermal energy source can heat the environment withdraw to the heat engine to drive, or for example, be a device that is operated by means of existing fuels on the vehicle and the Heat engine drives.

It is provided according to the invention that the heat engine works bidirectionally, so both works as a motor to the generator to drive, as well as a heat pump works to heat the exhaust gas purifier.

After this it is particularly provided according to the present invention, to use the existing in the exhaust of the engine heat energy to the heat engine To supply the generator with thermal energy is to drive a bidirectionally acting heat transfer device between the exhaust gas purifier and the heat engine intended.

About these bidirectionally acting heat transfer device can now heat energy transferred from the exhaust gas of the internal combustion engine to the heat engine which in turn are the generator for feeding the electric On-board voltage system of the vehicle drives and also from the heat engine originating heat transported in the direction of the exhaust gas purification device, to over to heat them up the exhaust gas purifier so that they have their intended operating temperature already has before the internal combustion engine is started.

To a development of the invention, it is provided that the exhaust gas cleaning device for chemical-thermal conversion of gaseous and / or solid exhaust gas constituents is trained. This can be used as a catalyst and / or for example Be designed diesel particulate filter.

The Heat engine can now be the so-trained exhaust purification device before starting the internal combustion engine heat up, so that compared with a cold Emission control device, the conversion rate already intended values possesses, before the heat energy present in the exhaust gas of the internal combustion engine would be able to bring the exhaust gas purification device to operating temperature.

at the aforementioned self-sufficient heat energy source This may be one embodiment For example, act to a vehicle auxiliary heating, so that in Operation of the auxiliary vehicle heater with the engine stopped on the Heat engine the generator for supplying the on-board voltage network with electrical energy can be driven and / or the exhaust gas purification device can be heated without this being necessary, the Running internal combustion engine.

In order to is in a hybrid vehicle also an extended operation with electric motor support possible, Existing energy in the exhaust gas can be used to feed the on-board voltage network be used and the heat engine can be used both for this supply of the on-board voltage network be as well as for heating the exhaust gas purification device, so that an efficient exhaust gas conversion also already immediately after the start of the internal combustion engine is possible.

To a development of the invention, it is provided that the heat engine After the Stirling comparison process works with in a closed Cycle guided Working medium, so that the operation of the heat engine, a feed pump or the like is not required.

The Heat engine has one with working fluid from a first higher temperature in Contact standing first rotary piston and one with working medium second in contact with a second lower temperature Rotary piston, both rotary pistons having a piston raceway are in contact such that between the piston and the piston raceway respective working medium receiving working spaces are formed and the rotary pistons are rotatably mounted on a first shaft and the piston raceways a rotational movement relative to the rotary pistons at a distance run to the second shaft arranged second shaft and with the second shaft are rotatably connected.

in the Contrary to known, working according to the Stirling comparison process Heat engines So this heat engine is characterized characterized in that the rotary pistons perform a pure rotational movement, without that they are superimposed on a translation movement and the same Perform a pure rotary motion piston strokes, so are not formed stationary and this pure rotational movement a rotary motion around the rotating rotary pistons around represents.

The Piston raceways are rotatably connected to the second shaft, which is located at a distance from the first wave is such, that between the respective center axes of the first and second Waves is a clear center distance and the two waves parallel to each other. Through this training is achieved that the moving rotary pistons and the moving piston tracks a continuous Perform rotary motion around each fixed, by the respective center of gravity of the respective moving parts passing through axes and thus no free mass forces or moments arise.

The moving parts therefore perform pure rotational movements and ensure a smooth running of the heat engine. The rotary pistons and the first shaft provided for their arrangement can therefore also be regarded as a common unit and, since they rotate within the piston raceway, are referred to as internal rotors. In a corresponding manner, the piston raceways and provided for their inclusion second shaft be regarded as a unit and accordingly be referred to as external rotor.

The has provided here heat engine a range of working medium of the first higher temperature is in contact and an area with working medium of second lower temperature than the first higher temperature in contact stands. The working medium is in a closed loop in the working process guided and between the first, hot Working room and the second, cold working space pushed back and forth and leaves thus the heat engine not and therefore does not have to be by means of a feed pump the process constantly fed again become.

The Heat engine works according to the Stirling comparison process, which consists of two isotherms and there are two isochores. The one acted upon by the first, higher temperature Work space is over an external heat source heated to perform work in the context of isothermal expansion to be able to tapped as Nutzmoment or working torque on the heat engine can be. As a heat source for the Heating the hot Working space can now according to the invention, the hot exhaust gas the internal combustion engine are used.

To The invention therefore provides that a heat supply to the first working space in contact with the first piston takes place in such a way that by means of a largely isothermal expansion the working fluid at the second shaft an output torque available is.

Internal combustion engines are usually with a catalytic exhaust purification device operated to harmful components after-treatment in the exhaust gas of the internal combustion engine. Such catalysts need for efficient implementation, an operating temperature, which after the Start of the internal combustion engine is not immediately available, which is why the pollutant content in the exhaust immediately after the start of the engine rises abruptly and gradually decreases until the catalyst has reached its operating temperature and works as intended.

Around now to eliminate this problem, it is after a training the invention also provides that a heat supply to that with the second Piston is in contact with second working space and takes place a coupling of work into the second wave such that the first working space in contact with the first piston Heat is dissipated.

It In other words, this means that the heat engine is also for implementation a left-turn Stirling comparison process is provided to the heat engine not as a motor, but as a heat pump, can be provided over the heat, with which the catalyst of the internal combustion engine is preheated, so that the conversion rate of the catalyst does not increase gradually, but the catalyst already immediately after the start of the internal combustion engine its Operating temperature has reached and its intended emission control can perform.

Of the Stirling comparison process works with an isothermal compression, their supplied Volume change work equal to the payable heat is. Now to the required volume changes in the workspaces on To be able to perform first or on the second piston, it is provided that between the working medium with different temperatures receiving workrooms based on the relative position of the working spaces to the first wave Rotation angle offset on the heat engine is provided. This rotation angle offset or phase angle between the hot ones and cold rotary pistons generated for passing through the Stirling Comparison process necessary volume changes in the workrooms.

Known, own heat engines operating according to the Stirling comparison process a provided with a reciprocating cylinder and a with a piston provided with compression cylinders, both pistons via piston rods are connected to a crankshaft. This configuration makes it is clear that with one revolution of the crankshaft or one so that comparable flywheel only one stroke is available.

Around now, in contrast, the power density of here provided Heat engine too increase, it is provided that at the first shaft a plurality of in Rotation angle offset is provided to each other arranged rotary piston pairs, those offset at the same angle of rotation on the second shaft Piston raceway pairs are assigned. Under a rotary piston pair is the smallest unit of a first and second rotary piston to understand. If now several such rotary piston pairs, which corresponding Piston raceway pairs are assigned, provided on the first shaft are, so it becomes possible while one revolution corresponding to the number of rotary piston pairs Number of work cycles to perform, and thus from the heat engine significantly increase the performance provided.

Similarly, the power density can also be increased by adding, per combination from rotary piston and associated piston barrel not only a working space is provided, but a plurality of such work spaces, for which purpose the rotary piston may have a corresponding n-angular configuration and the number of n-1 work spaces per combination of rotary piston and piston career is created. This can be created by the combination of a sub-combination of rotary piston and piston track with multiple work spaces arranged with a further or more such sub-combinations on the first and second shaft, a heat engine, which operates according to the Stirling comparison process and compared with known Stirling machines achieved a significantly higher power density ,

to Realization of the volume change in the workrooms It is provided according to a development of the invention that the first and the second shaft coupled by means of a transmission in a predetermined transmission ratio are, so that there is a rotation of the piston raceway relative to The also rotating rotary piston comes and thus the between Piston runway and rotary piston trained working space a volume change experiences. In this way, for example, a gear ratio of 2: 3 can be achieved, so that at two revolutions of the rotary piston the piston barrel performs three turns, making it the required volume change comes.

Around now with a training of the heat engine provided here with a A plurality of rotary pistons and a corresponding plurality of piston races the axial dimensions of the first and second shaft with it arranged rotary piston or piston raceways not to grow strongly, it is envisaged that the piston races at disk-shaped housing components are formed as cycloids, in particular trochoidal and the Rotary disk-shaped body are with at least two circumferentially equidistantly arranged corners. The Rotary pistons move in such an embodiment in disc-shaped housing parts whose radial Innenkontoren formed by cycloids, in particular trochoid are. The disc-shaped housing parts with their predefined by Trochoids or cycloids Inner contours are also around that already defined above certain phase angle twisted against each other and over the second shaft firmly connected.

Either it can be the first wave as well as the second wave to act a hollow shaft that keeps the mass of the heat engine low.

As it already explained above was, the working fluid between the hot working space and the cold Working space pushed by the rotation of the rotary piston back and forth. In order to realize this, It is provided according to a development that fluid-conducting channels between adjacent first and second work spaces are provided.

These fluid-conducting channels can now according to one embodiment be arranged within the first wave. Is it now the volume change in the workrooms, this is how the working medium becomes this shifted arranged in the first shaft fluid-conducting channels. The heat transfer towards the first one, hot Workspace into and out of the second, cold workspace takes place in this configuration via the piston raceway or the external rotor, like it has been defined above.

During the Arbeitszyklusses can in this way a sinusoidal course of change of the Work volume can be achieved. Going now from the ideal Stirling Comparison process, this ideal Stirling process requires but a, based on the rotation angle change shortened running back of the Expansion piston in the dead center.

A sinusoidal change the working volume, as in the arrangement of the fluid-conducting channels in the first wave or the inner rotor is the case leads to a Reduction of the efficiency of the heat engine, as the sinusoidal course the change of the working volume based on the rotation angle change of the first shaft corresponding fast run-down of the expansion piston in the dead center not allowed.

Around To avoid this reduction in efficiency, it is also envisaged that the fluid-conducting channels outside the first wave, in particular within the second wave and the Piston raceways forming housing components are arranged. By this arrangement of the housing components can in conjunction with the rotating rotary piston a slot control will be realized. For this purpose, it is provided that the fluid-conducting channels in the workrooms in the area swept by the rotary piston during the rotary motion side surface run in such that the connection opening between channel and working space controlled by the rotary piston, opened and getting closed. The configuration thus provided also leads to an enlargement of the for the Heat transfer effective area and thus to an improvement in the efficiency of the heat engine according to the invention.

By the provision of several of the rotary piston to open and close the connection openings in the fluid-conducting channels between the cold and the warm working space can also be the volume flow be controlled accordingly and thus influenced How quickly the expansion piston returns to the dead center.

In the fluid-conducting channels can the heat engine can Regenerators be provided or the fluid-conducting channels in regenerators lead, the energy transfer between the isochoric heating and cooling processes of the Accomplish working medium.

at These regenerators are heat storage devices that when transporting the hot Working medium in the direction of the cold working space absorb heat and when returning from the cold working space towards the hot working room again heat to the Release working medium.

Finally is It also provided that the heat engine in a thermally insulated casing is arranged and arranged with the also within the housing and coupled to the second shaft coupled generator, which is the from the heat engine discharged mechanical energy converts into electrical energy, the is used to the on-board voltage system of the motor vehicle Food.

Around now the heat engine for preheating a catalytic exhaust gas purifier to be able to it is finally provided that a heat exchange device is coupled to the first and / or second working space, via the then heat can be registered in the catalyst to this example before the start of the engine already at operating temperature so that also immediately after starting the internal combustion engine already a complete one Proper exhaust gas cleaning takes place.

The The invention will be explained in more detail below with reference to the drawing. These shows in:

1A a longitudinal sectional view of an embodiment of a heat engine, as can be used according to the present invention;

1B a sectional view according to AA after 1A ;

2A a representation similar 1A a modified embodiment of a heat engine;

2 B a sectional view according to AA after 2A ;

3 Representations of various embodiments of rotary piston and piston raceways; and

4 a schematic representation of a drive system according to an embodiment according to the present invention.

1A shows a longitudinal sectional view of a heat engine 1 as they are closer to 4 the drawing apparent drive system can be used.

It is a so-called 2: 3 machine, in which a Speed ratio from rotary piston to piston raceway of 2: 3 is present.

The heat engine 1 is in a case 2 arranged, which in the illustrated embodiment, a spur gear stage 3 does not surround, in a modified embodiment, this spur gear stage 3 but can completely include.

The heat engine working according to the Stirling comparison process 1 has two rotary pistons in the illustrated embodiment 4 . 5 , which - as this is closer to 1B can be seen, are offset by a phase angle α. This phase angle is required for it to be during the rotary motion of the rotary pistons 4 . 5 at the common first wave 6 to an entry on volume change work in a not shown working medium between the between the rotary piston 4 . 5 and a respective piston barrel 8th . 9 formed workrooms comes.

The piston tracks 8th . 9 are on disc-shaped housing components 10 . 11 out forms, the inner contour corresponds to a trochoid, as shown by 1B is apparent. The likewise disk-shaped and in the drawings stylized triangular illustrated rotary piston 4 . 5 run inside the trochoid of the respective housing components 10 . 11 on the piston races thus formed 8th . 9 and form between outer surfaces of the rotary piston and the inner surface of the respective piston raceway during the relative rotation of the piston raceways 8th . 9 and the rotary piston 4 . 5 mutually enlarging or reducing working spaces.

Due to the phase angle offset between the adjacent rotary pistons 4 . 5 and the corresponding phase angle offset between the adjacent piston liners 8th . 9 it comes with the relative rotation of the piston raceways 8th . 9 to the rotary pistons 4 . 5 for the described volume change work.

At the in 1A illustrated embodiment is the working space between the rotary piston 4 and housing component 10 , which the piston career 8th carries, heat supplied. This heat comes from the closer by 4 the drawing apparent drive system 16 the internal combustion engine schematically shown there 17 , It becomes the heat engine 1 about as a catalyst 18 trained exhaust gas purification device supplied by means of a bidirectional heat exchanger, not shown.

This heat supply leads, following the idealized Stirling comparison process, to an expansion in which work is performed by the working medium, which ultimately takes the form of a useful moment on the housing components 10 . 11 bearing second shaft, a hollow shaft 12 can be tapped, for example, with a generator 19 can be coupled, which converts the available mechanical energy into electrical energy with which, for example, the on-board voltage system of the vehicle can be fed.

The heated working medium is via the fluid-conducting connection channel 7 in which a heat storage device - not shown in detail - a regenerator - is arranged, transported in the direction of the second working space, which between the second rotary piston 5 and the second housing component 11 or the second piston career 9 is trained. Here, the working fluid undergoes a largely isochoric cooling, as it is brought by heat removal to the regenerator back to the initial state. Then learns the working fluid through the rotary piston 5 a largely isothermal compression, it comes to the heat dissipation through the housing component 11 ,

In the next working cycle, the working fluid is then transferred via the rotary piston 5 through the connection channel 7 back towards the between the rotary piston 4 and the housing component 10 shifted working space, where it is above the in the channel 7 arranged regenerator is guided while experiencing a warming. The cycle starts again. In this way, the heat engine according to a clockwise Stirling comparison process can be operated as a motor to drive the generator contained in the exhaust gas of the engine, which feeds the vehicle voltage system of the motor vehicle.

After an alternative use of the heat engine, it is also possible to use this as a heat pump according to a left-handed Stirling comparison process. For this purpose, heat is fed into the colder side of the heat engine, for example, from a latent heat storage or the like. In addition, mechanical work is registered via, for example, the then motor-driven generator, which is fed from the on-board voltage network of the vehicle. This leads in the left-handed Stirling comparison process that on the warmer side of the heat engine, heat is available from a higher temperature level, which there tapped via the heat exchanger and the exhaust gas catalyst 18 the internal combustion engine 17 can be supplied to bring this to operating temperature, even before the internal combustion engine 17 has been started.

This ensures that the exhaust gas catalyst 18 immediately after the start of the internal combustion engine 17 works with a high conversion rate and not first until it reaches its operating temperature due to the exhaust gas of the internal combustion engine 17 has a worse conversion rate, as he has hot or warm operating condition. In this way, by means of the heat engine, the exhaust gas pollution of the environment by the internal combustion engine 17 of the vehicle can be reduced.

About the in 1A schematically illustrated insulation 13 . 14 the warm or cold area of the heat engine are separated from each other or the warm area additionally from the other housing interior.

2A respectively 2 B show a heat engine similar to the one after 1A respectively 1B with the difference that in the embodiment according to 1A within the first wave 6 arranged fluid-conducting channels 7 in the presentation according to 2A have been eliminated and the fluid-conducting channels and the regenerator 15 in the area outside the first wave 6 have been moved and thus in the area of the external rotor, by the second wave 12 and the housing components 10 . 11 is formed.

The openings of the fluid-conducting channels 7 after the presentation in 2A respectively 2 B that the reference 16 carry, are during the rotation of the rotary piston 4 . 5 and the housing components 10 . 11 relative to each other from the rotary pistons 4 . 5 opened or closed, so that in this way a slot control can be realized. About a suitable arrangement of the openings 16 in the side walls of the housing components 10 . 11 In this way, a good approximation to the ideal course of change of the working spaces according to the Stirling comparison process can be achieved.

3 The drawing now shows various embodiments of rotary piston 4 or 5 and associated piston liners 8th or 9 , In the upper left representation, a so-called 1: 2 configuration is shown, in which there is a speed ratio of the inner rotor 4 and the outside runner 8th comes from 1: 2. The upper right illustration shows the configuration, which is also in 1A . 1B and 2A . 2 B is shown, namely a rotary piston 4 with three equidistantly distributed corners and a trochoid 8th , The lower left illustration in 3 shows a rotary piston 4 with four corners, a corresponding cycloid 8th is assigned, so that there is a speed ratio of 3: 4. Finally, the lower right shows in 3 an inner rotor 4 or rotary piston 4 with five equidistant corners and an associated cycloid 8th , so that there is a speed ratio of 4: 5.

The here provided heat engine draws So it is characterized by the fact that with her in the exhaust of internal combustion engines contained residual energy converted into mechanically usable drive energy can be, for example, by means of the generator, the on-board voltage network to feed the vehicle and thus increase the overall efficiency and reduce the pollution of the environment. The moving components to lead a continuous rotary motion out to a fixed, respectively by the center of gravity of the moving parts going axis of rotation. There are none free mass forces due to, for example, translationally moving components. By the possibility, the number of workrooms as it were without restriction to increase, Is it possible, per revolution of the torque-emitting shaft several work processes run concurrently, resulting in a significant increase in the Power density results.

4 The drawing shows a schematic representation of a possible arrangement of a heat engine 1 between the catalytic converter 18 and the generator 19 , About the catalytic converter 18 is in the exhaust of the internal combustion engine 17 contained heat of the heat engine 1 fed, which operates after the Stirling process and via a guided in a closed circuit working medium the generator 19 drives, with which the on-board voltage network of the vehicle can be fed. This ensures that the heat energy contained in the exhaust gas can be used to charge the on-board voltage network of the vehicle. In this case, the heat engine works 1 as engine after a right-handed Stirling process.

Will the generator 19 operated as a motor, so it can be in the cold side of the heat engine 1 mechanical work can be entered. About a non-illustrated heat energy source, which may be, for example, a vehicle auxiliary heating, is in the cold side of the heat engine 1 Heat entered, the heat engine 1 works according to a left-handed Stirling process as a heat pump and is the entry of heat in the exhaust gas purification device 18 , In this way, the exhaust gas purification device 18 be heated regardless of whether the internal combustion engine 17 running or not, leaving the exhaust gas purifier 18 already immediately after the start of the internal combustion engine 17 has its operating temperature and its intended conversion rate even with still cold engine 17 having.

Regarding not closer in detail Illustrated Features of the invention will be otherwise expressly on the claims and the drawing referenced.

1

Heat engine

2

casing

3

gear stage

4

rotary pistons

5

rotary pistons

6

first wave

7

fluid-conducting channels

8th

Piston path

9

Piston path

10

housing component

11

housing component

12

second wave

13

insulation

14

insulation

15

regenerator

16

drive system

17

Internal combustion engine

18

catalyst

19

generator

Claims (20)

Drive system for a vehicle with internal combustion engine ( 17 ) and exhaust gas purification device ( 18 ) and a generator ( 19 ) for feeding an electrical voltage system of the vehicle, characterized by a heat energy of the internal combustion engine ( 17 ) and / or a self-sufficient heat energy source of the vehicle powered heat engine ( 1 ) used to power the generator ( 19 ) and / or for heating the Abgasrei cleaning device ( 18 ) is trained. Drive system according to claim 1, characterized by a bidirectionally acting heat transfer device between the exhaust gas purification device ( 18 ) and the heat engine ( 1 ). Drive system according to claim 1 or 2, characterized in that the exhaust gas purification device ( 18 ) is designed for the chemical-thermal conversion of gaseous and / or solid exhaust gas constituents. Drive system according to one of the preceding claims, characterized characterized in that the heat energy source a vehicle auxiliary heating is. Drive system according to one of the preceding claims, characterized in that the heat engine ( 1 ) works according to the Stirling comparison process with guided in a closed circuit working medium. Drive system according to claim 5, characterized in that the heat engine ( 1 ) a first rotary piston in contact with working fluid from a first higher temperature ( 4 ) and a second rotary piston in contact with working fluid from a second lower temperature ( 5 ) and both rotary pistons ( 4 . 5 ) with a respective piston barrel ( 8th . 9 ) are in contact such that between rotary pistons ( 4 . 5 ) and piston career ( 8th . 9 ) each of the Ar beitsmedium receiving working spaces are formed and the rotary piston ( 4 . 5 ) on a first wave ( 6 ) are arranged rotationally fixed and the piston raceways ( 8th . 9 ) a rotational movement relative to the rotary pistons ( 4 . 5 ) at a distance from the first wave ( 6 ) arranged second wave ( 12 ) and with the second wave ( 12 ) are rotatably connected. Drive system according to claim 6, characterized by a heat supply to the first rotary piston in contact with the first working space such that by means of a largely isothermal expansion of the working fluid on the second shaft ( 12 ) An output torque for driving the generator can be provided. A drive system according to claim 6, characterized by a heat supply to the second working chamber in contact with the second rotary piston by means of the heat energy source and by an input of work into the second shaft ( 12 ) by means of the motor-operated generator in such a way that heat can be dissipated for heating the exhaust gas purification device at the first working space in contact with the first rotary piston. Drive system according to one of claims 6 to 8, characterized in that between the working medium with different temperatures receiving work spaces relative to the relative position of the work spaces at the first time ( 6 ) A rotation angle offset (α) is provided. Drive system according to one of claims 6 to 9, characterized in that on the first shaft ( 6 ) a plurality of rotational angle offset from each other arranged rotary piston pairs are provided, which on the second shaft ( 12 ) offset in the same angle of rotation arranged piston running track pairs are assigned. Drive system according to one of claims 6 to 10, characterized in that the first and the second shaft ( 12 ) are coupled by means of a transmission in a predetermined transmission ratio. Drive system according to one of claims 6 to 11, characterized in that the piston raceways on disk-shaped housing components ( 10 . 11 ) are formed as cycloids, in particular trochoid. Drive system according to one of claims 6 to 12, characterized in that the rotary pistons ( 4 . 5 ) Disc-shaped bodies are with at least two circumferentially equidistantly arranged corners. Drive system according to one of Claims 6 to 13, characterized by fluid-conducting channels ( 7 ) between adjacent first and second work spaces. Drive system according to claim 14, characterized in that the fluid-conducting channels ( 7 ) within the first wave ( 6 ) are arranged. Drive system according to claim 14, characterized in that the fluid-conducting channels ( 7 ) outside the first wave ( 6 ), especially within the second wave ( 12 ) and piston races ( 8th . 9 ) forming housing components ( 10 . 11 ) are arranged. Drive system according to claim 16, characterized in that the fluid-conducting channels ( 7 ) in the working spaces in the area of one of the rotary piston ( 4 . 5 ) merge in the rotational movement swept side surface such that the connection opening between the channel and working space from the rotary piston ( 4 . 5 ) controlled open and closed. Drive system according to one of claims 6 to 17, characterized in that in the area between the first and second working space a heat is arranged. Drive system according to one of Claims 6 to 18, characterized by a heat engine ( 1 ) surrounding heat-insulated housing ( 2 ), in which also the generator with the second wave ( 12 ) is arranged coupled. Drive system according to one of claims 6 to 19, characterized by one with the first and / or second working space for heat transfer coupled heat exchange device.