DE202006018097U1 - Free piston engine - Google Patents

Abstract

Free-piston engine, the compressed gas both with a supercharger (14, 54, 58, 90, 92, 124, 154, 244, 258, 260, 304, 444, 470, 498, 500) as well as a turbine (16, 78, 302, 432, 434), characterized in that the free-piston engine (18, 52, 84, 108, 126, 130, 133, 160, 222, 236, 253, 318, 478) at least one in a cylinder space (74, 196, 198, 200, 202, 204, 206, 208, 210, 458, 460, 488) and this in two combustion chambers (136, 138, 144, 146, 292, 294, 490, 492, 38, 336, 338, 362, 364, 394, 396, 398, 400; 266, 267, 270, 271) dividing piston (20, 50, 72, 110, 128, 132, 134, 162, 164, 166, 168, 170, 172, 280, 316, 356, 358, 390, 392, 420, 422, 424, 426, 462, 464, 480) and that the supercharger is actuated electrically and / or exhaust gas assisted.

Description

The The invention relates to a free-piston engine, the Druckgasmäßig both is connected to a supercharger and a turbine

Of the present invention is based on the object, a corresponding in particular as a multi-fuel engine usable free-piston engine in such a way, that this is compact and lightweight, a low specific Fuel consumption shows only a few components, one long life guaranteed and essentially oil and maintenance free. there should be a universal use for land, Water and air vehicles possible be. Likewise, by means of the engine also electrical energy can be generated. Other units should be able to be driven, just like vehicles themselves.

to solution The invention is essentially provided that the free-piston engine at least one in a cylinder chamber and movable back and forth having this dividing into two combustion chambers piston and that the supercharger is actuated electrically and / or exhaust gas assisted.

According to the invention is a Free-piston engine, in particular a multi-fuel engine proposed the at least 2 or 2 × n combustion chambers and Accordingly, 1 or n-piston, which optionally added or disconnected can be. For the Combustion chambers or spaces even a single supercharger is basically needed, if one Multistage can be considered. Independent of this the supercharger is electric, gas-dynamic or mechanical driven directly by the turbine. Also the possibility of one or more Turbine stages is given, at least with an output shaft can be provided. The turbine stages are primarily of the flowing gases from the combustion chambers applied.

Of the Inventive multi-fuel engine can z. B. as a diesel engine, turbofan engine, turboprop engine or used as a helicopter main propulsion, in addition to the compressor and the turbine, a generator may be provided, which runs in the middle between two bearing points.

By chemical compression, admixture of substances to the actual Fuel may be the power z. B. for the aircraft take-off or emergency / escape performance without damage all Engine components considerably be increased.

Of the Depending on the version used, the pre-compressor can be used Take on the task of a starter. If the free piston engine is assigned a generator, this can for driving land and rail vehicles or watercraft be dimensioned so that by means of the generator, an electric drive arises, which is also used as a hybrid drive for z. As cars or trucks are used can. In addition, there is also the possibility that by means of a transmission, hydrostatic or hydrodynamic or mechanical converter, the multi-fuel motor take over the direct drive can.

To the Can use any compressors come. Exemplary are Roots blowers, vane or to call screw compressors. One the following compressor function executive Compressor and the turbine or its wheel can by a shaft of a generator out. Alternative or supplementary may be provided a separate compressor, in turn especially about an electric motor is driven.

To an embodiment The invention provides that the piston emanating from the free end faces Piston rods, the openings the combustion chambers, the compressed gas with the compressor or the turbine are connected, release or close. Consequently Separate valves are not required.

It However, there is also the possibility as a piston within the cylinder chamber back and forth movable Cylinder - in particular Hollow Cylinder Body - to use the outlet openings z. B. over Solenoid valves open or closed.

Of the through the piston into the combustion chambers divided cylinder space has at least one gas inlet opening on that over a check valve shut off or is releasable, so that on the one hand when compressing gas can escape when the boost pressure is greater than the pressure in the cylinder chamber. Independently flows from it always pre-compressed gas into the cylinder chamber when the pressure in this is smaller than the boost pressure. This gives you a better degree of filling.

Further it is possible, that the free piston engine, d. H. whose combustion chamber or -spaces, over one Multi-stage supercharger gas is supplied.

Valve-free design of the combustion chambers does not only result from the piston starting from piston rods which close or open the outlet openings. Rather, it is provided according to a development of the invention that the piston itself releases the outlet openings in dependence on its position or ver closes. Thus, no moving elements are required, which allow high vibration frequencies with a simple structure of the engine.

Around an undesirable warming of the free-piston engine, i. its piston and thus its housing to avoid is provided that the piston of a preferably coaxial its longitudinal axis passing through passage opening is that pass into Hohlwellen- or pipe sections, which in turn openings in the free-piston engine housing prevail and opposite this is sealed. Thus, there is a possibility that a cooling fluid flows through the piston and thus the desired cooling causes.

Preferably are the compressor and the turbine on both sides of a generator arranged on the shaft. However, there is also the possibility that compressor and turbine on one side of a generator on the shaft are provided. On the opposite side can one Compressed air generator such as turbocharger be arranged to then supplied compressed air to a consumer. Similarly, a Pump or other units are driven.

additional Electrical energy can be gained by having the piston partially formed as a magnet or has such and that the piston is in the range of motion of the magnet from a coil or more coils is surrounded. It is preferably provided that the housing surrounding the piston circumference having corresponding coils. By a related arrangement there is also the possibility to start the free piston by placing several side by side Coils are energized in necessary clocking, so that the piston a back and forth Heruction forced becomes.

Around To gain mechanical energy, there is the possibility that the generator shaft over a Transmission is connected to another shaft. Thus, the effect Generator shaft as output shaft.

The gas outlets of the free-piston engine, regardless of the number of pistons, flow in a common line leading to the turbine. there From the line a branch can go out, which in another Turbine discharges, which emanates from a wave on the z. B. arranged a turbo compressor is that over the electric motor is operated.

To Another suggestion to be emphasized is that the Free piston engine has two oppositely moving piston, preferably Are connected to each other gas-dynamically. The latter is characterized causes, that between the in each case inside and in each case outside combustion chambers a pressure equalization enabling Connections run. However, this is not a mandatory feature.

The Invention includes also the possibility of that of the compressor a connection to a heat exchanger as well as an air release device that leads from the generator shaft emanates. Thus, cooling air to disposal posed.

Around to achieve high performance in a compact design, the invention proposes in that the free-piston engine has two groups of pistons, wherein the pistons of a group in the same direction and the groups in opposite directions swinging back and forth to each other. This can be the movement the groups to each other or the piston in the group z. B. electronically be controllable. freed thereof the pistons mechanically separated, but gas-dynamic be connected to each other by motion-dependent acting in the same direction Combustion chambers connected via pressure equalization channels are.

Especially It is envisaged that the pistons of a group pass through one another a piston rod are connected, optionally as a hollow shaft can be designed to provide cooling to enable. At the same time there is a mass reduction.

Detached from this there is a possibility that the free-piston engine several along a common cylinder peripheral surface and movable pistons comprises, which together via a or more compressors compressed air is supplied. It is therefore around a ring assembly, wherein the gas outlets of the combustion chambers with each other are connected. Furthermore, can the combustion chambers adjacent piston communicate with each other, wherein a Shut off each other over Valves possible is. The connection allows a gas-dynamic control of the piston movement. Regardless of can However, to optimize the working symmetry or ge wished Power piston except Operation, then the connections to the adjacent combustion chambers be shut off. The common exhaust port for the combustion gases can be referred to as a flame tube.

In the case of groups of pistons having a free-piston engine, it is possible, in particular, to pre-compact the gas to be supplied to the combustion chambers by means of the group movement. Also, a corresponding free-piston engine can be used as a pump. For this purpose, it is provided that zwi rule the groups in a mutually movable piston with an inlet and outlet provided by lateral boundary walls limited space which is peripherally surrounded by the motor housing or its cylinder. One boundary wall each starts from one of the groups. The inlet of the room can be connected to a compressor and the outlet to the combustion chambers. However, the space may also be used as a pump room so that the inlet communicates with a reservoir of a medium to be conveyed and the outlet communicates with a location to which the medium is to be pumped.

Around a sufficient cooling to achieve the piston, there is a possibility that the piston out two spaced-apart cylinder discs, whose space is connected to the form of a hollow shaft piston rod.

Of Further, from the piston rod, regardless of their construction, a Magnet go out, the one or more of the free piston housing outgoing Coil is assigned. This can generate electrical energy become. Conversely, by pulsed current application of in longitudinal direction the cylinder running coils starting or starting the Motors done.

A preferred embodiment of the free-piston engine provides that the combustion chamber a single effective gas outlet has, that the piston two spaced apart at least partially having circumferential grooves of each groove at least within of the piston and in the longitudinal direction this extending, nutnaheliegender end face of the piston opening out Channel out, the grooves are so positio ned that each in a dead center position of the piston one of the grooves with the gas outlet opening in Connection stands.

Detached from the above it is possible, that in the combustion chamber or the combustion chamber in addition to the leading to the compressor Connection a compressed air connection opens. There is also the possibility that a pulsed injection into the combustion chambers of the Free-piston engine performed becomes. In this case, a two-stage combustion is possible, d. h. that during the Relaxing the gas injected a portion of the combustion medium becomes.

Of the Piston, the housing, the turbine wheel and / or its blades can be made of ceramic or high heat resistant lightweight materials, so that a temperature-stable, however light unit available stands.

A Another embodiment of the invention provides that the combustion chambers the free-piston engine with a supercharger pressure gas moderately connected are, which emanates from a shaft of a generator or electric motor, and that on the shaft is arranged a turbine wheel of another turbine is, the pressurized with the gas outlet openings the combustion chambers is connected. This results in particular in exhaust-assisted pre-compression a fuel supply in a pipe connecting the exhaust ports of the combustion chambers connects with the other turbine.

A further self-inventive development of the invention provides that from each end of the piston of the free-piston engine a Piston rod assumes that from each piston rod one each Section of the cylinder of the free-piston engine in a first and a second precompression space dividing piston disc assumes that with respect to the piston of the free-piston engine, the outboard Vorverdichtungsräume with each other and the internal pre-compaction rooms also are interconnected and that the precompression rooms with the combustion chambers themselves are connected. It is in particular provided that the connection between the precompression spaces and the combustion chambers over an accumulator takes place.

On this way you can the combustion chambers with pre-compressed to the desired extent Gas or desired Amount of gas to be applied.

The Invention is also characterized in particular by the fact that the Free-piston engine arranged in a jet drive with jet outlet opening is that the free piston engine has a longitudinal direction of the jet propulsion oscillate back and forth a first and a second combustion chamber includes limiting piston, which extends in the axial direction Through opening has that of Strahlaustrittsöffnungsseitig extending face of the piston emanating from the passage opening hollow cylinder, in dependence from the position of the piston beam outlet opening side extending first combustion chamber opposite the jet outlet opening releases or shuts off, and that in the second combustion chamber arranged an axially extending cylinder body is that dependent from the position of the piston whose passage opening releases or shuts off.

There is the possibility that the cylinder body is a precompressed second air chamber air (back pressure) supplying hollow cylinder or surrounding the combustion chambers wall of the free-piston engine is at least partially surrounded by an annulus, via the precompressed air (back pressure) of the first and / or second combustion chamber can be fed.

Of Furthermore, the invention provides that two free-piston engines with arranged in opposite directions oscillating piston in a jet drive are and that gas outlets the combustion chambers of the free - piston engines in an annular space of Jet propulsion open, which merges into the jet outlet opening. In this case, a fuel supply is provided in the annular space.

Especially the invention is also characterized by the fact that for driving a Aircraft several free piston engines on the peripheral surface of a Cylinders are arranged so that the peripheral surface coaxial with a generator or compressor is running and that of the shaft of the generator or the compressor, a turbine wheel emanates.

Especially can on both sides of the generator or compressor of the Wave a wheel of a turbine goes out.

going on one side of the generator or the compressor of the shaft an impeller and from the other side of a turbine wheel, so there is a turbofan drive.

It there is also the possibility that the shaft of the generator or the compressor has an output shaft is that over the stepped gear, a hydrostatic or hydrodynamic Converter or other mechanical converter with a drive shaft is in active connection

A Another embodiment provides that on one side of the generator or the compressor of the shaft starting a turbine wheel and on the other side a compressor are arranged, which with a a ring assembly forming free piston engines surrounding annular space connected to the one with the combustion chambers of the free-piston engines and on the other hand connected to a bleed air outlet.

Further Details, advantages and features not only result from the claims, the characteristics to be taken from these - alone and / or in combination - but also to be taken from the following description of the drawing preferred embodiments.

It demonstrate:

1 A first embodiment of a free-piston engine in an energy converter system,

2 A second embodiment of a free-piston engine in an energy converter system,

3 A third embodiment of a free-piston engine in an energy converter system,

4 A fourth embodiment of a free-piston engine in an energy converter system,

5 A fifth embodiment of a free-piston engine in an energy converter system,

6 a modification of the free-piston engine according to 3 .

7 a modification of the arrangement according to 6 .

8th A sixth embodiment of a free-piston engine in an energy converter system,

9 A seventh embodiment of a free-piston engine in an energy converter system,

10 a variant of the free-piston engine according to 9 .

11 a variant of the arrangement according to 6 .

12 a modification of the arrangement according to 11 .

13 an eighth embodiment of a free-piston engine in an energy converter system,

14 a variant of the free-piston engine according to 13 .

15 A ninth embodiment of a free-piston engine in an energy converter system,

16 A tenth embodiment of a free-piston engine in an energy converter system,

17 a modification of the free-piston engine according to 16 .

18 a further modification of the free-piston engine according to 16 .

19 a further embodiment of a free-piston engine in an energy converter system,

20 a turboprop drive,

21 a first embodiment of a jet engine,

22 a second embodiment of a jet engine,

23 a third embodiment of a jet engine,

24 A fourth embodiment of a jet engine,

25 a drive with free-piston engines in a ring arrangement,

26 a turbofan drive,

27 Another embodiment of a drive with gear or converter,

28 another embodiment of an engine,

29 a further embodiment with a free-piston engine with a piston in a first position and

30 the free piston engine after 29 with the piston in a second position.

In the figures, in which in principle identical elements are provided with the same reference numerals are different embodiments of free-piston engines in connection with energy converter systems described with which in turn z. B. generates electrical energy can be. However, this does not limit the inventive teaching, not just other use cases for use according to the invention free-piston engines possible but other types of energies are generated as well can like Pressure or cooling air.

at The description itself is based on details of aggregates described like compressor, turbine or generator not discussed in detail since it is This is about components that the average expert in sufficient extent. In that regard, is based on conventional designs and types resorted without leaving the invention.

In 1 an energy converter system is shown, which is a generator 10 with rotor shaft 12 , a compressor 14 as well as a turbine 16 includes, emanating from the generator or rotor shaft. As a compelling component - in addition to the compressor and the turbine - is also a free-piston engine 18 provided that may be designed differently according to the various embodiments. The compressor 16 is about the free piston engine 18 gas flow with the turbine 16 connected, as can be seen from the illustration.

The free-piston engine 18 has a piston 20 on, in a hereinafter referred to as a cylinder housing 22 swingable back and forth. From the piston 20 , and of its front sides 24 . 26 go piston rods 28 . 30 out, the outlet openings 32 . 34 of combustion chambers 36 . 38 enforce such that, depending on the position of the piston 20 during compression, the opening of the corresponding combustion chamber is closed and opened when relaxing. This results in a valveless arrangement, wherein the gas outlet openings 32 . 34 over a line 40 with the turbine 16 valveless via the piston rods 28 . 30 closed or opened.

A central gas inlet 42 preferably has a check valve 44 on.

The embodiment of 2 is different from that of 1 in that the gas outlet openings 32 . 34 through solenoid valves 46 . 48 be opened or closed. One in the cylinder 22 swinging piston back and forth 50 is designed as a hollow cylinder body. This results in mass savings, so that high frequencies can be achieved.

The 3 differs from the embodiments of the 1 and 2 to the effect that a free piston engine 52 not one from the generator shaft 12 outgoing compressor 54 Compressed air can be supplied. For this purpose, an electric motor 56 that has a converter 58 with the generator 10 electrically connected, are used. From the motor shaft 60 goes the compressor 54 out, over a line 68 with a connection 62 of the free-piston engine 52 connected, the two gas inlets 64 . 66 includes, in which check valves 66 . 68 can be arranged. The inlets 64 . 66 flow into the combustion chambers or chambers 36 . 38 in which, in the drawing, a piston shown as a solid cylinder 72 swingable back and forth. Of course, the piston 72 also a construction according to the 2 exhibit.

In the middle in which the combustion chambers 36 . 38 comprehensive cylinder space 74 of the cylinder 22 runs a gas outlet 76 which depends on the position of the piston 72 closed or opened. Thus, the control is done via the piston 72 even without the need for additional valves.

The over the gas outlet 76 flowing exhaust gas is via a pipe 78 on the one hand the turbine 16 and on the other another turbine 78 fed by the motor shaft 60 emanates.

By connecting the gas outlet to the turbine 78 can after starting without synonymous Power supply to the motor 56 the z. B. designed as a turbocharger compressor 54 are driven. The motor 56 can then if necessary the compressor 54 drive support or as an additional generator z. B. be pulled out for the system supply. Furthermore, it follows from the graphic representation of 3 that the rotor shaft 12 via a gearbox 80 with another wave 82 can be put into operative connection, so that the shaft 12 performs the function of an output shaft.

The storage of the waves 12 . 60 can be done via air or magnetic bearings. It is also possible to change the speed, so as to be able to set the desired flow rate of compressed air. Possibilities in this regard are available in all embodiments. Furthermore, the generator 10 that is, the stator windings are cooled, for example, with liquid nitrogen. Also, superconducting materials for the stator winding can be used to have to accept low energy losses and to meet the thermal aspect because of the speed-related small dimensions. At a power of 100 kW, the stator diameter is about 100 mm to 150 mm with a length of about 150 mm to 250 mm.

With reference to the embodiment of 4 should be clarified that a multi-stage precompressed gas a free-piston engine 84 is supplied. To do this go from a wave 86 an electric motor 88 compressor 90 . 92 out, the compressed air connected. From the downstream compressor 90 then leads a line 94 to inlet openings 96 . 98 of the free-piston engine 84 So, to the combustion chambers 36 . 38 out. From the movement of the piston 72 be outlet openings 100 . 102 shut off or opened to according to the embodiments of the 1 to 3 the turbine 16 , ie to act on the turbine wheel with exhaust gas. In addition, there is the possibility that the combustion chambers 36 . 38 over a line 104 precompressed air via an inlet opening 106 is fed, in the middle region of the cylinder space 74 empties. The administration 104 goes by one of the 3 corresponding unit coming out of the compressor 54 , Electric motor 56 and turbine 78 consists. However, in the embodiment of the 4 the motor 56 not electrically with the generator 10 connected, if possible.

An energy conversion system according to 5 differs from the previous embodiments essentially in that a free-piston engine 108 is used, the piston 110 is coolable. To do this, go from the faces 112 . 114 of the piston 110 hollow shafts 116 . 118 out, in a through hole 120 of the piston 110 go over, coaxial with the longitudinal axis 122 of the piston 110 runs.

Thus, there is the possibility through the hollow shafts 116 . 118 to flow a cooling fluid through which the piston 110 and thus the cylinder 22 , So the housing of the free-piston engine 108 is cooled.

The control of the gas outlets 100 . 102 takes place according to the embodiment of 4 , Further, flows into the cylinder chamber 74 in the middle region of the gas inlet opening 106 over the line 104 with the compressor 14 is different from the embodiment of the 1 and 2 in terms of the turbine 16 on the opposite side of the generator 10 from the wave 12 emanates.

One of the 1 and 2 corresponding arrangement of turbine 16 and compressors 14 is found in the 6 , where the compressor 14 and the turbine 16 fluidically with the combustion chambers 36 . 38 or the cylinder space 74 of the housing 22 according to the explanations 5 are connected. Deviating from this illustration, an uncooled piston is used, which is the 4 equivalent.

The embodiment of 7 is in terms of the 6 further developed such that of the generator shaft 12 on the opposite side of the compressor 14 and the turbine 16 another compressor 124 starting, which can perform the function of a turbo compressor to produce compressed air, which is to be supplied to a consumer or exert, for example, a turbo pump for liquid media.

Another possibility of an energy conversion results from the 8th which is a system to extract in relation to the generator 10 , the compressor 14 , the turbine 16 as well as the gas inlet and outlet openings 102 . 104 . 106 of the cylinder space 74 functionally the embodiment of 6 equivalent. Deviating from this, a free-piston engine 126 a piston 128 on, which is designed as a magnet or contains such, wherein the cylinder chamber 74 circumferentially of one or more coils 128 is surrounded, so that during the reciprocation of the piston 128 Current is induced. Become several coils 128 energized, the result is the effect of a starter.

The embodiments of the 9 and 10 agree on generator 10 , Compressor 14 and turbine 16 with the previously explained examples. Also, the opportunity is given to the wave 12 of the generator 10 as a drive shaft to use this over the gearbox 80 with a on drive shaft 82 connect to. Furthermore, in the 9 and 10 in principle indicated that as a compressor 14 Any type can be used. So is in 9 an example of a Roots blower 124 and in 10 a vane compressor 126 shown.

Deviating from the embodiments described above, free-piston engines arrive 128 respectively. 130 used, the two oppositely oscillating piston 132 . 134 exhibit.

It is in 9 between the internal combustion chambers 136 . 138 extending partition 140 broken, whereas those in 10 closed and with the reference numeral 142 is marked.

The opening 141 in the partition 140 of the free-piston engine 128 along with one the outer combustion chambers 144 . 146 connecting line 143 offers the possibility that all combustion chambers 136 . 138 . 144 . 146 are connected gas-dynamically. Otherwise, there is a construction with respect to gas inlet and outlet, as this 4 to 6 it can be seen, so valveless opening and closing of the gas inlet and outlet openings 102 . 104 . 106 , so that the same reference numerals are used.

The combustion chambers 144 . 136 respectively. 138 . 146 of each piston 132 . 134 are in the previously described manner with the compressor 14 or the turbine 16 connected.

Based on 11 should be clarified that there is the possibility not only to generate electrical energy, but also cooling air. For this purpose, the embodiment of 6 further developed such that of the shaft 12 , in relation to the generator 10 on the opposite side to the compressor 14 and the turbine 16 , a relaxer 148 going out, via a heat exchanger with a pipe 50 with a line 152 connected via the compressor 14 with the gas inlet 106 connected is. Thus, with structurally simple measures, it is possible to generate cooling air.

An alternative embodiment results from the 12 , This is different from the one of 11 to the effect that on the shaft 12 another compressor 154 is arranged, via a heat exchanger 156 with a relaxer 158 fluidically connected to produce cooling air. The compressed air of the compressor 154 is not supplied to the free-piston engine. Otherwise, the structure of the 12 the the 6 ,

Was on hand of the 9 and 10 clarifies in principle that an inventively used free piston engine can have more than one piston, so convey the drawings of the 13 to 18 the possibility of using free-piston engines with more than two pistons.

An Indian 13 illustrated free piston engine 160 has a total of six pistons 162 . 164 . 166 . 168 . 170 . 172 on that in two groups 161 . 163 are divided, namely the piston 162 . 164 . 166 on the one hand and the pistons 168 . 170 . 172 on the other hand. This is the free-piston engine 160 operated in such a way that in each group 161 . 163 existing pistons 162 . 164 . 166 respectively. 168 . 170 . 172 swing in the same direction, but the groups in opposite directions to each other. The supply of compressed air takes place in the usual way via the compressor 14 who has a lead 174 with inlets 176 . 178 . 180 . 182 . 184 . 186 Combustion spaces, which are not identified in more detail, are connected to the respective pistons 162 . 164 . 166 . 168 . 170 . 172 are limited. The combustion chambers are via pressure equalization lines 191 . 193 connected without this being a mandatory feature.

The outlets of the respective combustion chambers are via a common line 192 with the turbine 16 connected, the wheel in the manner previously described by the shaft 12 of the generator 10 emanates. It can be the wave 12 via a gearbox 80 with another wave 82 be mechanically coupled. By way of example, two of the gas outlets with the reference numerals 188 . 190 characterized.

Are the pistons 162 . 164 . 166 . 168 . 170 . 172 arranged in series, so there is also the possibility of a ring arrangement, as this in principle from 14 is recognizable. In a motor housing 194 extend on a circle cylinder chambers 196 . 198 . 200 . 202 . 204 . 206 . 208 . 210 in which pistons not shown are movable back and forth. The gas inlets, one of which is the reference numeral 112 carries, are with each other and with the compressor 14 connected. The gas outlets, one of which in turn is identified purely by way of example and with the reference numeral 214 is provided, open into a common channel 216 that's to the turbine 16 leads.

The individual cylinder chambers 196 . 198 . 200 . 202 . 204 . 206 . 208 . 210 are interconnected. In this case, the connection can be shut off by valves, not shown, for example, if a partial load is desired or if cylinders are individually preferably switched on or off in pairs.

Is the embodiment of the 13 an arrangement shown with independently moving pistons, ie the mechanical are not coupled, but whose movement can be electronically synchronized, so the embodiment of the 16 the possibility of being in groups 161 . 163 combined pistons 162 . 164 . 166 , respectively. 168 . 170 . 172 mechanically via a common piston rod 218 respectively. 220 connect to. Also in the embodiment of 16 has the illustrated free piston engine 222 a total of six pistons in the groups 161 . 163 are summarized. In that regard, the reference numerals corresponding to 13 used. It should be noted, however, that the number of pistons can also be smaller and in particular larger.

The piston rods 218 . 220 can be designed as a hollow shaft for weight reduction and optionally acted upon by a cooling fluid. The individual combustion chambers of the free-piston engine 222 that of the pistons 162 . 164 . 166 . 168 . 170 . 172 are completed according to the 16 via lines 174 . 192 with the compressor 14 or the turbine 16 connected. In that regard, like reference numerals are used.

Additionally or alternatively, the free-piston engine 222 also be used as a pump. So go from the groups 161 . 163 The piston 162 . 164 . 166 respectively. 168 . 170 . 172 opposite the inner wall 224 the free piston engine housing sealed cylindrical piston discs 226 . 228 out, which is a room 230 limit, an inlet 232 and an outlet 234 having. Because the groups 161 . 163 The piston 162 . 164 . 166 . 168 . 170 . 172 moving in opposite directions will increase the volume of the room 230 correspondingly reduced and enlarged, so that there is a pump effect.

In the embodiment of the 17 , which is a free-piston engine 236 is to be taken from a basic structure as the 16 shows, in addition to the pumping action in addition the possibility that the piston discs 226 . 228 more chambers 238 . 240 limit, with the trained as hollow shafts piston rods 218 . 220 are connected to flow through them for cooling with air.

The 17 clarifies in addition that of the room 230 originating air an air conditioning 240 can be supplied. This is the room 230 over a line 242 with a compressor 244 connected, the ventilation technology via a heat exchanger 246 to a relaxer 248 leads, the cooling air can be seen. compressor 244 and relaxers 248 go from a wave 250 a generator 252 out. The one from the room 230 Compressed air can also be used for post-oxidation and admixture with the hot gases after leaving the combustion chambers to increase the mass flow rate.

In the embodiment of the 18 go from the piston rods 218 . 220 Although from their mutually facing end portions not shown magnets from which one or more coils 252 are coaxially surrounded the magnets to generate electrical energy. Conversely, so if several coils 252 be energized successively, the function of a linear starter. Otherwise, the one of the 18 to be taken free piston engine on a construction that those of 16 and 17 corresponds, so that reference is made to the relevant remarks.

Of the 15 is a free-piston engine 253 to refer to its combustion chambers 292 . 294 be subjected to multi-stage precompressed compressed air. In this case, a further pre-compression of the compressed air takes place in the motor housing itself. Part of the multistage can be done on the one hand by separate Vorverdichteranordnungen, as these the 3 or 4 can be seen. In this case, a pre-compression can also take place without exhaust gas support.

In the embodiment of 15 is a precompaction stage 254 drawn in principle, the an electric motor 256 with wave 262 as well as on opposite sides of the electric motor 256 arranged compressors 258 . 260 includes. From the fluid second compressor 260 leads a line 264 to connections 263 . 265 in the housing or cylinder 282 of the free-piston engine 252 lead, and previously in compression areas 266 . 267 passing through a piston disc 272 are separated, with a first piston rod 276 a piston 280 of the free-piston engine 252 connected is. The precompression rooms 266 . 267 are over lines 268 . 269 with compression areas 270 . 271 connected with respect to the piston 280 opposite to the compression chambers 266 . 267 are arranged. The compaction rooms 270 . 271 are through another piston disc 274 separated by a second piston rod 277 emanates. The piston discs 272 . 274 thus practice the movement of the piston 280 with out.

By a related arrangement is a multi-stage pre-compression, namely the first pre-compression on the compressor 258 . 260 and further precompressions in the chambers 266 . 267 . 270 . 271 , The chambers 270 . 271 are then over connections 284 . 286 with a pressure accumulator 288 connected, in turn, via the connection shown in dashed lines 290 with the combustion chambers 292 . 294 of the free-piston engine 252 are connected.

Alternatively or additionally, an exhaust-assisted pre-compression can take place. This is a pre-compression unit 296 with electric motor 298 in front seen from its shaft 300 a turbine 302 and a compressor 304 emanates. The turbine 302 is over a line 306 with outlets 308 . 310 the combustion chambers 292 . 294 connected and the compressor 304 with the chambers 266 . 267 over the connections 263 . 265 to which the line 264 leads.

The in the Vorverdichterräumen 266 . 267 Pre-compressed air is - as described above - over the lines 268 . 269 to the pre-compressor rooms 270 . 271 passed over the wires 284 . 286 with the accumulator 288 are connected. This is at exhaust assisted pre-compression with the combustion chambers 292 . 294 via a central inlet 312 connected.

Furthermore, it follows from the 15 that in the pipes 268 . 269 a heat exchanger 314 can be arranged.

Of the 19 is a preferred embodiment of a piston 316 a free-piston engine 318 to remove the previously described manner with the compressor 12 and the turbine 14 connected by ventilation. To start, the generator 10 be used as an electric motor.

The piston 316 , which is preferably designed as a hollow cylinder piston, has two mutually spaced preferably circumferential grooves 320 . 322 on, of which in the longitudinal direction of the piston 316 extending and in the respective proximate end face 324 . 326 opening channels 328 . 330 . 332 . 334 go out, over the pre-compressed air to the respective combustion chamber 336 respectively. 338 is supplied. For this purpose, the circumferential grooves 320 . 322 such to each other and to the faces 324 . 326 spaced, that in dependence on the position of the piston in each dead center position a connection with a gas inlet opening 340 consists. Further, go from the combustion chambers 336 . 338 in the usual way outlet channels 342 . 344 out to the turbine 14 to lead.

One of the 19 corresponding energy converter is in 20 As turbo propulsion for aviation is in the 20 shown, wherein the 19 corresponding elements are provided with the same reference numerals. Complementing the wave 12 a propeller 346 out.

The 21 to 23 are energy converter systems refer to the use or drive of manned or unmanned aircraft, especially ultralight aircraft, gliders or auxiliary equipment. Such are various embodiments of jet engines 348 . 350 . 352 shown a housing 354 with in this reciprocating piston 356 . 358 by which of the housing 354 surrounded cylinder space 360 in combustion chambers 362 . 364 is divided.

The pistons differ 356 . 358 essentially by the fact that the piston 358 a solid cylinder and the piston 356 to the extent massively lighter that the piston of two end walls 357 . 359 and a hollow cylinder connecting them 361 whose outer diameter is considerably smaller than that of the Kolbenstirnwandung 357 . 359 is. It results in the average H-shape.

Regardless, each piston has 356 . 358 a passage opening 366 on that on a gas outlet 368 or outlet nozzle 370 is aligned.

So in the combustion chambers 322 . 364 Fuel gas mixture can be compressed to the extent required, goes from the to the exhaust gas outlet opening 368 or outlet nozzle 370 opposite end wall 372 of the rear combustion chamber 362 an optionally end tapered cylinder element 373 . 374 off, the the through hole 366 when moving the piston 356 . 358 in the direction of the front wall 372 closes.

To the compression in the combustion chamber 364 to allow, goes from the gas outlet side extending face 376 of the piston 356 . 358 a hollow cylinder 378 from, the aligned in the passage opening 366 passes over and has an extent such that when moving the piston 356 . 358 in the direction of the exhaust gas outlet opening 368 or nozzle 370 these opposite the combustion chamber 364 is completed.

In the usual way - as in the other embodiments also - preferably from the Stirnbegrenzungswandungen the combustion chambers 362 . 364 Fuel injectors off. Pre-compressed air enters the combustion chambers 362 . 364 via an inlet opening 380 , wherein in central arrangement a single inlet opening is needed. Of course, every combustion chamber can 362 . 364 be assigned a separate inlet opening. There is also the option of additional compressed air via connections 382 . 384 into the combustion chambers 362 . 364 feed.

In the embodiments of the 22 . 23 there is the possibility of that in the outlet nozzle 370 In addition, fuel is injected to burn the remaining oxygen. Furthermore, the outlet nozzle 370 from a pipe 386 Coaxially surrounded to influence the jet thrust.

A jet engine 388 is in principle in the 28 shown. The drive 388 includes two oppositely oscillating piston 390 . 392 as is the case in principle 10 has been illustrated and explained. The pistons 390 . 392 , which have the geometry of a cylinder, are in combustion chambers 394 . 396 respectively. 398 . 400 movable back and forth. The combustion chambers 394 . 396 respectively. 398 . 400 are over several the wall of the combustion chambers 394 . 396 . 398 . 400 surrounding cylinder 402 passing exhaust gas outlet openings 404 . 406 run in an annulus 408 connected to the outlet nozzle 410 passes.

There is a possibility in the annulus 408 , outside of the combustion chambers 394 . 396 . 398 . 400 surrounding housing of the pistons 390 . 392 inject additional fuel to burn existing oxygen and thus to achieve a further thrust increase.

The combustion chambers 394 . 396 . 398 . 400 Pre-compressed air to be supplied may be via a pre-compressor arrangement, such as those in US Pat 15 illustrated and explained and with the reference numerals 296 is provided. Therefore, corresponding reference numerals are used.

In the of the annulus 408 outgoing and to the turbine 302 leading line 412 it is also possible to inject fuel (element 414 ). The one between the turbine 302 and the compressor 304 existing electric motor 298 can after starting the drive perform the function of a generator, so that electrical energy is obtained.

From the drawings of the 21 and 22 further results that by back pressure precompressed gas into the combustion chambers 362 . 364 can flow. For this purpose, according to the embodiment of the 21 that the passage opening 366 closing cylinder element 373 be designed as a hollow cylinder, so tube. In the embodiment of the 22 is that the combustion chambers 362 . 364 surrounding housing 354 double-walled, so that an annulus 355 arises over which the required pre-compressed air combustion chambers 362 . 364 is supplied.

Further embodiments of the invention will become apparent from the 25 to 27 , which - like each of the individual figures to be taken embodiments - ownfinderischen content.

The representations of the 25 and 26 refer to drives, in particular for aerospace, without this being a restriction. The 25 - as well as the 26 and 27 - include free-piston engines 416 . 418 . 420 . 422 , which correspond to the representations or explanations of the 14 several pistons 420 . 422 . 424 . 426 comprise, which are arranged on the peripheral surface of a cylinder, so that there is a so-called ring assembly. The pistons can 420 . 422 the structure and function of the 1 correspond. The pistons 424 . 426 have on average an H-shape, as this in connection with the 21 has been explained. Other suitable geometries are also possible.

The ring arrangement of the pistons 420 . 422 surround an electric motor 428 , from its shaft 430 a first and a second turbine 432 . 434 with fixed wheel 436 . 438 and running bike 440 . 442 out. The turbines 430 . 432 are on both sides of the engine 428 on the wave 430 arranged.

In the embodiment of the 25 surround the pistons 424 . 426 of the free-piston engine 418 a compressor 444 , in particular of a previously described type, of the shaft 446 on the one hand a turbine wheel 448 and on the other a wheel 450 go out of a fan. The blower of the blower wheel 450 leads air to an annulus 452 to, that the piston assembly of the free-piston engine 418 Coaxially surrounds. By constructing it, you get a turbofan engine. To operate the free piston of the free-piston engine 418 are the unspecified, but from the Zeichendar position clearly recognizable combustion chambers of the piston 424 . 426 preferably charged with diesel fuel.

One of the 26 corresponding arrangement with respect to the free-piston engine and the compressor and the turbine is the 27 to be taken so that the same reference numerals are used.

The compressor shaft 446 , which performs the function of an output shaft, is via a preferably stepped transmission 450 with a wave 452 connected to provide a mechanical drive. The step transmission 450 However, of course, can also be replaced by a hydrostatic, hydrodynamic or other mechanical converter.

A trained as a multi-fuel engine energy converter according to 28 can be used for example as a combined heat and power plant, with process heat is dissipated by heat exchangers. According to the explanatory notes to the 25 becomes a generator 456 coaxial with cylinder chambers 458 . 460 surrounded in which flask 462 . 464 are swinging back and forth, so a ring assembly of free-piston engines how this relates to the 14 has been described.

From the wave 466 of the electric motor 456 goes a turbine wheel 468 out. On the opposite side is on the shaft 466 a compressor 470 provided over the combustion chambers of the free-piston engines, so the cylinder chambers 458 . 460 be charged with precompressed air. For this flows from the compressor 470 incoming air preferably in an annulus 472 , which communicates with the graphically represented gas inlet openings which lead to the individual combustion chambers. In front of the annulus 472 can furthermore via a line 474 Are drawn bleed air that a consumer, such. B. an air conditioner is supplied.

Furthermore, the generator 456 in a frequency converter 476 be connected. In that regard, however, reference is made to well-known techniques.

The rotor diameter of the turbine in the arrangement according to 28 may have a diameter between 20 cm and 30 cm and produce a power of 200 kW to 250 kW, to give only numerical values. Only two bearing points are required, such as magnetic or air bearings.

The 29 and 30 shows a further embodiment of an energy converter system, which is a free-piston engine 478 includes, whose pistons 480 has an H-shape in section, as this in connection with the embodiment of 21 has been explained. In other words, the piston points 480 two outer piston discs 482 . 484 on, via a connecting element, preferably in the form of a cylinder 486 connected to each other. The piston 480 divided according to the teaching of the invention, a cylinder chamber 488 in two combustion chambers or chambers 490 . 492 to which pre-compressed air via inlets 494 . 496 each of a compressor 498 . 500 is supplied. The compressors 498 . 500 go from a common wave 502 out, via an electric motor 504 is drivable. By a related arrangement, the compression during operation of the free-piston engine 478 be determined freely, regardless of the extent and extent of the combustion chambers 490 . 492 pre-compressed air is supplied. The same applies to the other examples.

The cylinder space 488 has an outlet 505 on that with a turbine arrangement 506 connected, which allows a gradual combustion. So has the turbine arrangement 506 two stationary wheels 508 . 510 on which running wheels 512 . 514 assigned. The wheels 512 . 514 go from a common wave 516 out, on which a generator or the runner 518 a generator is attached. In that regard, reference is made to the explanations in the preceding embodiments. In addition to these is in the 29 and 30 the injection of fuel into the turbines indicated.

The the 29 and 30 to be taken embodiments are intended to illustrate that the turbine assembly 506 a gas stream is supplied substantially continuously, without causing large pulsations. It is possible to optimize the mass flow rate, with an additional internal cooling of the piston 480 as well as a simple way a post-oxidation is possible.

The internal cooling of the piston is achieved in that, depending on the position of the piston 480 the between the piston discs 482 . 484 existing gap 520 a connection between the inlet openings 494 . 496 and the exit opening 505 during the compression of the fuel gas mixture in the combustion chambers 492 . 494 or when relaxing allows. That's how it shows 29 in that during the compression of the fuel gas mixture in the chamber 490 over the inlet opening 496 a connection to the outlet 505 over the combustion chamber 492 consists. Moves the piston 480 to the right, so is through the piston disc 484 though the inlet opening 496 temporarily shut off, but without the connection to the turbine assembly 506 flowing gas is suppressed; because when shutting off the inlet opening 496 is about the interior 520 of the piston 480 a connection to the turbine arrangement 506 produced. Accordingly, if the piston disc shown on the left in the drawing 482 the inlet 494 shut off, a connection through the inlet opening 496 , the interior 520 and the outlet opening 504 a passage to the turbine assembly 506 open.

The particular the 25 to 28 To be taken ring arrangements of free-piston engines, it should be noted that the number of cylinders can be selected according to the requirements. It is possible to individually switch on or off the individual cylinders. In this context, reference is made to the statements relating to the 14 directed.

10

generator

12

wave

14

compressor

16

turbine

18

Free piston engine

20

piston

22

Housing (cylinder)

24

front sides

26

front sides

28

piston rods

30

piston rods

32

outlet

34

outlet

36

combustion chamber

38

combustion chamber

40

management

42

Gas inlet port

44

check valve

46

magnetic valve

48

magnetic valve

50

piston

52

Free piston engine

54

compressor

56

electric motor

58

compressor

60

wave

62

connection

64

gas inlet

66

gas inlet

68

management

72

piston

74

cylinder space

76

gas outlet

78

turbine

80

transmission

82

wave

84

Free piston engine

86

wave

88

electric motor

90

compressor

92

compressor

94

management

96

inlet port

98

inlet port

100

management

102

outlet

104

outlet

106

inlet port

108

Free piston engine

110

piston

112

face

114

face

116

hollow shaft

118

hollow shaft

120

Through opening

122

longitudinal axis

124

compressor

125

Roots compressor

126

Free piston engine

127

Vane compressor

128

piston

129

Kitchen sink

130

Free piston engine

131

Kitchen sink

132

piston

133

Free piston engine

134

piston

136

combustion chamber

138

combustion chamber

140

partition wall

141

opening

142

partition wall

143

management

144

combustion chamber

146

combustion chamber

148

relaxer

150

heat exchangers

152

management

154

compressor

156

heat exchangers

158

relaxer

160

Free piston engine

161

group

162

piston

163

group

164

piston

166

piston

168

piston

170

piston

172

piston

174

management

176

inlet

178

inlet

180

inlet

182

inlet

184

inlet

186

inlet

188

gas outlet

190

gas outlet

191

Pressure equalizing line

192

management

193

Pressure equalizing line

194

casing

196

cylinder space

198

cylinder space

200

cylinder space

202

cylinder space

204

cylinder space

206

cylinder space

208

cylinder space

210

cylinder space

212

gas inlet

214

gas outlet

216

channel

218

piston rod

220

piston rod

222

Free piston engine

224

inner wall

226

piston disc

228

piston disc

230

room

232

inlet

234

outlet

236

Free piston engine

238

chamber

240

chamber

241

air conditioning

242

management

244

compressor

246

heat exchangers

248

relaxer

250

wave

251

Kitchen sink

252

generator

253

Free piston engine

254

supercharging

256

electric motor

258

compressor

260

compressor

262

wave

263

connection

264

management

265

connection

266

compression chamber

267

compression chamber

268

management

269

management

270

compression chamber

271

compression chamber

272

piston disc

274

piston disc

276

piston rod

277

piston rod

280

piston

282

cylinder

284

connection

286

connection

288

accumulator

290

connection

292

combustion chamber

294

combustion chamber

296

Vorverdichtungseinheit

298

electric motor

300

wave

302

turbine

304

compressor

306

management

308

outlet

310

outlet

312

inlet

314

heat exchangers

316

piston

318

Free piston engine

320

groove

322

groove

324

face

326

face

328

channel

330

channel

332

channel

334

channel

336

combustion chamber

338

combustion chamber

340

Gas inlet port

342

exhaust port

344

exhaust port

346

propeller

348

Jet engines

350

Jet engines

352

Jet engines

354

casing

355

annulus

356

piston

357

end wall

358

piston

359

end wall

360

cylinder

361

hollow cylinder

362

combustion chamber

364

combustion chamber

366

Through opening

368

Gas outlet

370

exhaust nozzle

372

bulkhead

373

cylindrical member

375

cylindrical member

376

face

378

hollow cylinder

380

outlet

382

connection

384

connection

386

pipe

388

Jet propulsion

390

piston

392

piston

394

combustion chamber

396

combustion chamber

398

combustion chamber

400

combustion chamber

402

cylinder

404

Exhaust gas outlet opening

406

Exhaust gas outlet opening

408

annulus

410

annulus

412

management

414

jet

416

drive

418

drive

420

piston

422

piston

424

piston

426

piston

428

electric motor

430

wave

432

turbine

434

turbine

435

wheel

437

wheel

439

wheel

438

step transmission

440

wave

441

wheel

444

compressor

446

wave

448

turbine

450

wheel

452

annulus

456

generator

458

cylinder space

460

cylinder space

462

piston

464

piston

466

wave

468

turbine

470

compressor

472

annulus

474

bleed air

476

frequency converter

478

Free piston engine

480

piston

482

piston disc

484

piston disc

486

cylinder

488

cylinder space

490

combustion chamber

492

combustion chamber

494

inlet opening

496

inlet opening

498

compressor

500

compressor

502

wave

504

electric motor

505

outlet opening

506

turbine assembly

508

wheel

510

wheel

512

wheel

514

wheel

516

wave

518

runner

520

gap

Claims (44)

Free-piston engine, the Druckgasmäßig both with a supercharger ( 14 . 54 . 58 . 90 . 92 . 124 . 154 . 244 . 258 . 260 . 304 . 444 . 470 . 498 . 500 ) as well as a turbine ( 16 . 78 . 302 . 432 . 434 ), characterized in that the free-piston engine ( 18 . 52 . 84 . 108 . 126 . 130 . 133 . 160 . 222 . 236 . 253 . 318 . 478 ) at least one in a cylinder space ( 74 . 196 . 198 . 200 . 202 . 204 . 206 . 208 . 210 . 458 . 460 . 488 ) and moving it into two combustion chambers ( 136 . 138 . 144 . 146 . 292 . 294 . 490 . 492 . 38 . 336 . 338 . 362 . 364 . 394 . 396 . 398 . 400 ; 266 . 267 . 270 . 271 ) subdividing pistons ( 20 . 50 . 72 . 110 . 128 . 132 . 134 . 162 . 164 . 166 . 168 . 170 . 172 . 280 . 316 . 356 . 358 . 390 . 392 . 420 . 422 . 424 . 426 . 462 . 464 . 480 ) and that the supercharger is actuated electrically and / or exhaust gas assisted. Free-piston engine according to claim 1, characterized in that the piston ( 20 ) of its free end faces ( 24 . 26 ) outgoing piston rods ( 28 . 30 ), the compressed gas with the turbine ( 16 ) connected gas outlet openings ( 32 . 34 ) depending on the position of the piston or close. Free-piston engine according to claim 1 or 2, characterized in that gas outlet openings ( 32 . 34 ) of the combustion chambers ( 36 . 38 ) via solenoid valves ( 46 . 48 ) are closable. Free-piston engine according to at least one of the preceding claims, characterized in that the compressor ( 54 ) on a wave ( 60 ) of an electric motor ( 56 ) is arranged. Free-piston engine according to at least one of the preceding claims, characterized in that the combustion chambers ( 292 . 294 ) via a multi-stage compressor ( 296 ) Gas can be supplied. Free-piston engine according to at least one of the preceding claims, characterized in that of the shaft ( 60 ) of the electric motor ( 56 ) a turbine ( 78 ), the compressed gas with the outlet openings ( 76 ) of the combustion chambers ( 36 . 38 ) connected is. Free-piston engine according to claim 1, characterized in that shaft ( 60 ) of the turbine ( 78 ) merges into, or is a section of, a generator's shaft. Free-piston engine according to at least one of the preceding claims, characterized in that the outlet openings ( 76 ) of the combustion chambers ( 36 . 38 ) valveless depending on the position of the piston are open or closed. Free-piston engine according to at least one of the preceding claims, characterized in that the piston ( 110 ) of a preferably coaxial with its longitudinal axis ( 122 ) extending passage opening ( 120 ) interspersed in hollow shaft or pipe sections ( 116 . 118 ), the openings in end walls ( 112 . 114 ) of the cylinder space ( 74 ) of the free-piston engine ( 108 ) and sealed against them. Free piston engine according to at least claim 9, characterized in that the hollow shaft or pipe sections ( 116 . 118 ) with a cooling medium can be flowed through. Free-piston engine according to at least one of the preceding claims, characterized in that the piston ( 128 ) is formed in sections as a magnet or has such and that the piston receiving cylinder space ( 74 ) in the range of movement of the magnet of at least one coil ( 129 . 131 ) is surrounded. Free-piston engine according to at least one of the preceding claims, characterized in that the compressor is a Roots blower ( 125 ) or a vane or screw compressor ( 127 ). Free-piston engine according to at least one of the preceding claims, characterized in that the free-piston engine ( 130 . 133 ) two oppositely moving pistons ( 132 . 134 . 162 . 164 . 166 . 168 . 170 . 172 ) having. Free-piston engine according to at least one of the preceding claims, characterized in that the oppositely moving pistons ( 132 . 134 . 162 . 164 . 166 . 168 . 170 . 172 ) are connected gas-dynamically. Free-piston engine according to at least one of the preceding Claims, characterized in that in the combustion chamber in addition to the Leading compressor Connection a compressed air connection opens. Free-piston engine according to at least one of the preceding claims, characterized in that the free-piston engine ( 160 ) two groups ( 161 . 163 ) of pistons ( 162 . 164 . 166 . 168 . 170 . 172 ), wherein the pistons of a group in the same direction and the groups in opposite directions to each other are movable back and forth. Free-piston engine according to at least one of the preceding claims, characterized in that the movement of the groups ( 161 . 163 ) is adjustable to each other. Free-piston engine according to at least one of the preceding claims, characterized in that the free-piston engine comprises a plurality along a common cylinder peripheral surface reciprocally movable piston whose combustion chambers are connected together with one or more compressors and the gas outlet openings ( 214 ) of the combustion chambers are interconnected. Free-piston engine according to claim 18, characterized in that between combustion chambers ( 214 ) adjacent piston passes a connection which can be shut off via a valve. Free piston engine according to at least one of the preceding claims, characterized in that between the in groups ( 161 . 163 ) in opposite directions to each other movable piston ( 162 . 164 . 166 . 168 . 170 . 172 ) with inlet and outlet ( 232 . 234 ) provided with piston movable with the piston ( 226 . 228 ) limited space ( 230 ) runs inside the motor housing. Free-piston engine according to at least claim 18, characterized in that the inlet ( 232 ) of the room ( 230 ) with one or the compressor ( 12 ) and the outlet ( 234 ) is connected to the combustion chambers. Free-piston engine according to at least claim 18, characterized in that the space ( 230 ) is a pump room. Free-piston engine according to at least claim 16, characterized in that the pistons ( 162 . 164 . 166 . 168 . 170 . 172 ) of a group ( 161 . 163 ) by a piston rod ( 218 . 220 ) are connected, which is designed as a hollow shaft. Free-piston engine according to at least claim 23, characterized in that the hollow shaft ( 218 . 220 ) can be acted upon with a cooling fluid. Free-piston engine according to at least one of the preceding claims, characterized in that the piston comprises two mutually spaced cylindrical discs, the intermediate space with the hollow shaft ( 218 . 220 ) connected is. Free-piston engine according to at least one of the preceding claims, characterized in that of the piston rod ( 218 . 220 ) emanating from at least one coil ( 251 ) is surrounded. Free-piston engine according to at least one of the preceding claims, characterized in that the cylinder space has a single effective gas inlet opening, that the piston ( 316 ) two mutually spaced preferably circumferential grooves ( 320 . 322 ) that of each groove at least one inside the piston and in the longitudinal direction extending Nutnaheliegende face ( 324 . 326 ) of the piston passing through the channel ( 328 . 330 . 332 . 334 ) and that the grooves are positioned such that in each case in a dead center position of the piston one of the grooves with the gas inlet opening ( 340 ). Free-piston engine according to at least one of the preceding claims, characterized in that the combustion chambers ( 292 . 294 ) of Free piston engine ( 253 ) with a pre-compressor ( 403 ) is connected by compressed gas, which by a wave ( 300 ) of a generator or electric motor emanates, and that on the shaft a turbine wheel of another turbine ( 302 ) is arranged, the compressed gas with the gas outlet openings ( 308 . 310 ) of the combustion chambers ( 292 . 294 ) connected is. Free-piston engine according to at least one of the preceding claims, characterized in that, in the case of exhaust-assisted pre-compression, a fuel feed ( 414 ) in a line ( 412 ) opening the outlet openings ( 408 ) of the combustion chambers ( 394 . 396 . 398 . 400 ) connects with the other turbine. Free-piston engine according to at least one of the preceding claims, characterized in that from each end face of the piston ( 280 ) of the free-piston engine ( 253 ) a piston rod ( 276 . 277 ) assumes that from each piston rod a respective portion of the cylinder ( 282 ) of the free-piston engine into a first and a second precompression space ( 266 . 267 . 270 . 271 ) dividing piston disc ( 272 . 274 ) assumes that, with respect to the piston, the external precompression chambers ( 266 . 270 ) and the internal compression chambers are each interconnected and that the precompression chambers with the combustion chambers ( 292 . 294 ) are connected. Free-piston engine according to at least claim 30, characterized in that the precompression chambers ( 266 . 267 . 270 . 271 ) with the combustion chambers ( 292 . 294 ) via an accumulator ( 288 ) are connected. Free-piston engine according to at least one of the preceding claims, characterized in that the free-piston engine is arranged in a jet drive with jet outlet opening, that the free-piston engine oscillates a longitudinally of the jet propulsion oscillating back and forth a first and a second combustion chamber ( 362 . 364 ) limiting piston ( 356 . 358 ) having an axially extending passage opening ( 366 ), that of Strahlaustrittsöffnungsseitig extending end face ( 376 ) of the piston in the passage opening overflowing hollow cylinder ( 378 ) emanating, depending on the position of the piston Strahlaustrittsöffnungsseitig extending first combustion chamber ( 374 ) opens or shuts off from the jet outlet opening, and that in the second combustion chamber ( 362 ) an axially extending cylinder body ( 373 . 374 ) is arranged, which releases or shuts off the passage opening in dependence on the position of the piston. Free-piston engine according to at least claim 32, characterized in that the cylinder body ( 373 ) one of the second combustion chamber ( 362 ) precompressed air (dynamic pressure) supplying hollow cylinder is. Free-piston engine according to at least one of the preceding claims, characterized in that the combustion chambers ( 362 . 364 ) surrounding wall ( 356 ) of the free-piston engine at least in sections from an annular space ( 355 ) is surrounded by the pre-compressed air (back pressure) of the first and / or second combustion chamber ( 362 . 364 ) can be fed. Free-piston engine according to at least one of the preceding claims, characterized in that two free-piston engines with oppositely oscillating pistons ( 390 . 392 ) are arranged in a jet drive and that gas outlet openings ( 404 . 406 ) of the combustion chambers ( 394 . 396 . 398 . 400 ) of the free-piston engines in an annular space ( 408 ) of the jet drive, which in the jet outlet opening ( 410 ) passes over. Free-piston engine according to at least claim 35, characterized in that in the annulus ( 408 ) A fuel supply is provided. Free-piston engine according to at least one of the preceding claims, characterized in that for driving, in particular for an aircraft, a plurality of free-piston engines are arranged on the peripheral surface of a cylinder such that the peripheral surface is coaxial with a generator ( 428 ) or compressor ( 444 ) and that of the wave ( 430 . 446 ) of the generator or of the compressor, a turbine wheel ( 440 . 442 . 448 ). Free-piston engine according to at least claim 37, characterized in that on both sides of the generator ( 428 ) or compressor ( 44e ) of its shaft ( 430 . 446 ) a wheel ( 442 . 444 ) a turbine ( 432 . 434 ). Free-piston engine according to at least one of the preceding claims, characterized in that the piston ( 480 ) in section an H-geometry with two outer piston discs ( 482 . 484 ) and this connecting element like cylinder ( 486 ) having. Free-piston engine according to at least claim 39, characterized in that the piston discs ( 482 . 484 ) an interior ( 520 ) of the piston ( 480 ) and that via the interior a connection between gas inlet ( 494 . 496 ) of the combustion chamber (s) ( 490 . 492 ) of the free-piston engine ( 478 ) and its combustion gas outlet (s) ( 505 ) consists. Free-piston engine according to at least claim 40, characterized in that each combustion chamber ( 490 . 492 ) a separate gas inlet ( 494 . 496 ) and that depending on the position of the piston ( 480 ) one of the gas inlets or both gas inlets with the combustion gas outlet ( 505 ) is connected or are. Free-piston engine according to at least one of the preceding claims, characterized in that on one side of the generator ( 448 ) or the compressor ( 444 ) of its shaft ( 430 . 446 ) an impeller ( 450 ) and from the other side a turbine wheel ( 448 ) go out. Free-piston engine according to at least one of the preceding claims, characterized in that the shaft ( 446 ) of the generator ( 428 ) or the compressor ( 444 ) is an output shaft which via step transmission, a hydrostatic or hydrodynamic converter or other mechanical converter with a drive shaft ( 452 ) is in operative connection. Free-piston engine according to at least one of the preceding claims, characterized in that on one side of the generator ( 428 ) or the compressor ( 444 ) of its shaft ( 430 . 446 ) starting a turbine wheel ( 468 ) and on the other side a compressor ( 470 ) are arranged, which with an annular space surrounding by a ring assembly forming free-piston engines ( 472 ) is connected to the one with the combustion chambers of the free-piston engines and the other with a bleed air outlet ( 474 ) connected is.